Local anesthetic toxicity: different mechanisms for different
end points.
Weinberg G
University of Illinois, Chief, Anesthesia, Chicago VA, Westside
Division, Chicago, IL. Department of Anesthesiology and Intensive
Care Medicine, Kanazawa University School of Medicine, Kanazawa,
Japan.
[Medline record in process]
PMID: 11812729, UI: 21670897
Anesth Analg 2002 Feb;94(2):432-437
The Timing of Intravenous Crystalloid Administration and
Incidence of Cardiovascular Side Effects During Spinal Anesthesia:
The Results from a Randomized Controlled Trial.
Mojica JL, Melendez HJ, Bautista LE
Department of Surgery, School of Medicine, Universidad Industrial
de Santander.
[Record supplied by publisher]
We conducted a randomized clinical trial to evaluate the
efficacy of crystalloids in preventing spinal-induced hypotension
(SIH) and cardiovascular side effects (CVSE) in a group of
surgical patients. Participants were assigned to receive lactated
Ringer?s solution at 1?2 mL/min (Placebo group, n = 142);
lactated Ringer?s at 20 mL/kg starting 20 min before spinal
block (n = 130); or lactated Ringer?s at 20 mL/kg starting
at the time of spinal block (n = 132). SIH was defined as
a decrease of ?30% in baseline systolic blood pressure, and
CVSE as SIH plus nausea, vomiting, or faintness requiring
treatment. The incidence of SIH was similar in all treatment
groups. Compared to placebo, crystalloid administration at
the time of spinal block resulted in a significant reduction
in the proportion of patients developing CVSE from 9.9% to
2.3%. The corresponding relative proportion was 0.23 (95%
confidence interval, 0.07?0.78; P = 0.019), and one additional
case of CVSE was avoided for each 13 patients receiving crystalloids
at the time of spinal block instead of placebo. Administration
of crystalloids at the time of spinal block seems to be effective
because it provides additional intravascular fluids during
the period of highest risk of CVSE after spinal anesthesia.
IMPLICATIONS: Crystalloids are frequently administered to
nonobstetric patients minutes before spinal anesthesia to
prevent cardiovascular side effects (CVSE). This randomized
controlled trial shows that although crystalloids administered
before spinal block result in no clinical benefit, they significantly
reduce the risk of CVSE when administered at the time of spinal
block.
PMID: 11812714
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Anesth Analg 2002 Feb;94(2):415-6
Discitis associated with pregnancy and spinal anesthesia.
Bajwa ZH, Ho C, Grush A, Kleefield J, Warfield CA
Department of Anesthesia and Critical Care, Beth Israel Deaconess
Medical Center, Harvard Medical School, Boston, Massachussetts.
[Medline record in process]
Discitis (inflammation of the intervertebral disk) most commonly
develops as a rare complication of bacterial infection or
chemical or mechanical irritation during spine surgery (1)
with a postoperative incidence of 1%-2.8% (2). It is also
a complication of discography-the intradiscal injection of
saline or contrast material (3). The incidence of postdiscography
discitis is 1%-4% (3); no cases have been reported when prophylactic
antibiotics have been used, supporting the theory of bacterial
contamination (3). Although it is controversial whether discitis
can be caused by an aseptic or infectious process, recent
data suggest that persistent discitis is almost always bacterial
(4). Honan et al. (5) reported 16 cases of spontaneous discitis
and reviewed another 52 patients from the literature. In their
series, patients tended to have one or more comorbid conditions,
such as diabetes, vertebral fracture, or a preexisting spine
injury. Spontaneous discitis has also been associated with
advanced age, IV drug abuse, IV access contamination, urinary
tract infection, and immunocompromised states (5,6). No cases
of infectious discitis associated with pregnancy and spinal
anesthesia have been reported in the English literature. Discitis
presents as spasmodic pain in the back that may be referred
to the hips or groin (7). The pain may radiate to the lower
extremities. The erythrocyte sedimentation rate is usually
increased. Radiological changes in discitis include narrowing
of the intervertebral disk space, vertebral sclerosis, and
erosion of the end plates. The best diagnostic measure may
be magnetic resonance imaging (MRI) or a combination of bone
and gallium scanning (2). The mainstay for discitis treatment
is pain control and antibiotics; surgical intervention is
usually not required. Complications of discitis include intervertebral
fusion, epidural abscess, and paralysis. IMPLICATIONS: This
is a case report of a disk infection (discitis) caused by
the bacteria, Streptococcus bovis after spinal anesthesia
for cesarean delivery. S. bovis rarely causes discitis, and
spinal anesthesia for labor and delivery has not been reported
as a cause of discitis.
PMID: 11812710, UI: 21670878
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Anesth Analg 2002 Feb;94(2):385-8
The Effects of Intravenous Anesthetics and Lidocaine on
Proliferation of Cultured Type II Pneumocytes and Lung Fibroblasts.
Nishina K, Mikawa K, Morikawa O, Obara H, Mason RJ
Department of Anesthesia and Perioperative Medicine, Faculty
of Medical Sciences, Kobe University Graduate School of Medicine,
Kobe, Japan.
[Medline record in process]
Type II pneumocytes synthesize surfactant and differentiate
into type I pneumocytes to maintain the epithelium (1). Alveolar
type II cell proliferation is required for reepithelization
after acute lung injury (ALI) and is thought to minimize the
subsequent fibrotic response (1). Keratinocyte growth factor
(KGF) and hepatocyte growth factor (HGF) are among the most
potent mitogen for type II epithelial cells, but not for fibroblasts
in the lung (1). These growth factors attenuate several experimental
ALI models by promoting epithelial repair (2,3). Thus, KGF
and HGF may be a promising therapeutic approach to ALI. Critically
ill patients with ALI often receive IV anesthetics or sedatives
to facilitate mechanical ventilation. Furthermore, these patients
sometimes undergo bronchoscopy under local anesthesia to obtain
bronchoalveolar lavage fluid or to remove respiratory secretions.
Several IV and local anesthetics inhibit pro-liferation of
various cells including epithelium (4,5). If these anesthetics
impede proliferation of type II pneumocytes, this suppressive
effect may be a disadvantage for alveolar reepithelization
in the course of recovery from ALI. In this study, we examined
the effects of midazolam, propofol, ketamine, thiopental,
and lidocaine on proliferation of type II alveolar epithelial
cells using in vitro culture system. Because fibroblast proliferation
is a key event in late phase of ALI, inhibition of this fibroproliferation
is probably beneficial. Thus, we further determined whether
these anesthetics could regulate proliferation of lung fibroblasts.
In the current study, rolipram was used as a positive control.
In our previous preliminary experiment, we found that rolipram,
a phosphodiesterase inhibitor type IV, augments spontaneous
or KGF-/HGF-promoted type II cell proliferation (6). IMPLICATIONS:
Midazolam, ketamine, thiopental, propofol, or lidocaine did
not inhibit proliferation of cultured rat type II pneumocytes.
Our findings suggest that these anesthetics do not impede
alveolar reepithelization after acute lung injury.
PMID: 11812704, UI: 21670872
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Anesth Analg 2002 Feb;94(2):369-71
Electrocardiographic electrodes provide the same results
as expensive special sensors in the routine monitoring of
anesthetic depth.
Hemmerling TM, Harvey P
Department of Anesthesiology and Biomedical Department, Universite
de Montreal, Quebec, Canada.
[Medline record in process]
The Bispectral Index (BIS) is a mathematically derived electroencephalographic
(EEG) derivative that has been introduced to monitor depth
of anesthesia (1,2). The A-2000 BIS monitoring system (Aspect
Medical Systems, Inc., Newton, MA) is currently the only commercially
available system to monitor depth of anesthesia. In several
studies, its propensity to optimize the use of hypnotics to
maintain and achieve a certain depth of anesthesia has been
described (3,4). Some studies have even proposed that the
routine use of the monitoring system can decrease awareness
(1,5), an increasing factor in malpractice claims. The cost-benefit
calculations for BIS monitoring suffer from the fact that
like its predecessor, the 1000-A BIS monitor, the A-2000 BIS
monitoring system demands the use of expensive, special electrodes
(6). Although the application of the single-use BIS sensor
is very comfortable and easy to use, its high price of approximately
$10-20 US prevents many anesthesiologists from using it. Furthermore,
whereas the former model of the monitor (1000-A BIS monitor;
Aspect Medical Systems, Inc.) used standardized connectors,
which allowed the use of other electrodes such as electrocardiogram
(ECG), the new monitoring system makes this very difficult
because of special connectors that match the equivalent connector
at the proximal BIS sensor site. The purpose of this prospective
study was to compare BIS values derived from the original
BIS sensor with BIS values derived from commercially available
ECG electrodes. This comparison was made possible by designing
and manufacturing a connector allowing the use of ECG electrodes.
IMPLICATIONS: The Bispectral Index (BIS) monitor adequately
monitors depth of anesthesia. The routine use of this monitor
has been hampered by the benefit-cost equation because only
special expensive electrodes can be used. We examined the
agreement of BIS values obtained by original sensor electrodes
and commercial electrocardiogram (ECG) electrodes. These ECG
electrodes can replace more expensive BIS sensors.
PMID: 11812701, UI: 21670869
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Anesth Analg 2002 Feb;94(2):360-1
Anesthesia for electroconvulsive therapy in obese patients.
Kadar AG, Ing CH, White PF, Wakefield CA, Kramer BA, Clark
K
Departments of Anesthesiology and Pain Management and Psychiatry,
Cedars Sinai Medical Center, Los Angeles, California.
[Medline record in process]
IMPLICATIONS: Obese patients have successfully undergone
over 650 consecutive uncomplicated ECT treatments without
any special precautions at two major U.S. medical centers.
PMID: 11812699, UI: 21670867
Anesth Analg 2002 Feb;94(2):351-354
Chloroprocaine is Less Painful than Lidocaine for Skin Infiltration
Anesthesia.
Marica LS, O?Day T, Janosky JE, Nystrom EU
Department of Anesthesiology, The Western Pennsylvania Hospital,
Pittsburgh, Pennsylvania.
[Record supplied by publisher]
Skin infiltration of local anesthetics causes pain. In a
double-blinded protocol, 22 volunteers received random intradermal
injections to the volar surface of the forearm with each of
the following solutions: normal saline solution 0.9% (NSS),
lidocaine 1% (L), lidocaine 1% and sodium bicarbonate 8.4%
(L+BIC), 2-chloroprocaine 2% (CP), 2-chloroprocaine 2% and
sodium bicarbonate 8.4% (CP+BIC), and NaCHO(3) 8.4% (BIC).
Initially, each volunteer received an open-labeled injection
of NSS. A 100-mm visual analog scale (VAS, 1?100) was used
to assess pain with each injection. The pH of each solution
was stable for the length of the study. Repeated measures
of variance were used for analysis. The VAS scores (mean ?
SD) for open-label and blinded NSS injections were 15.5 ?
15.9 and 14.0 ? 18.1, respectively. The scores for the studied
solutions were as follows: BIC, 47.2 ? 25.5; L, 25.8 ? 27.6;
L+BIC, 16.0 ? 14.2; CP, 8.6 ? 7.4; and CP+BIC, 6.8 ? 6.7.
No significant difference was found between CP and alkalinized
CP, but the injection of both solutions was significantly
less painful than that of all other solutions (P < 0.05).
The pH of the solutions was not related to the pain score.
We found that chloroprocaine caused less pain at injection
than the more commonly used lidocaine. IMPLICATIONS: Using
2-chloroprocaine can diminish pain caused by the intradermal
injection of lidocaine. pH variations of the solution did
not relate to the pain profile of the local anesthetic.
PMID: 11812697
Anesth Analg 2002 Feb;94(2):346-350
Small-Dose Selective Spinal Anesthesia for Short-Duration
Outpatient Laparoscopy: Recovery Characteristics Compared
with Desflurane Anesthesia.
Lennox PH, Vaghadia H, Henderson C, Martin L, Mitchell GW
Departments of Anesthesia, Health Care and Epidemiology,
and Gynecology, Vancouver General Hospital, University of
British Columbia, Vancouver BC, Canada.
[Record supplied by publisher]
We conducted a randomized controlled trial to compare the
recovery characteristics of selective spinal anesthesia (SSA)
and desflurane anesthesia (DES) in outpatient gynecological
laparoscopy. Twenty ASA physical status I patients undergoing
gynecological laparoscopy were randomized to receive either
SSA with lidocaine 10 mg + sufentanil 10 ?g or general anesthesia
with DES and N(2)O. Intraoperative conditions, recovery times,
postanesthesia recovery scores, and postoperative outcomes
were recorded. Intraoperative conditions were comparable in
both groups. All patients in the SSA group were awake and
oriented at the end of surgery, whereas patients in the DES
group required 7 ? 2 min for extubation and orientation. SSA
patients had a significantly shorter time to straight leg
raising (3 ? 1 min versus 9 ? 4 min; P < 0.0001) and to
ambulation (3 ? 0.9 min versus 59 ? 16 min; P < 0.0001)
compared with the DES group. SSA patients had significantly
less postoperative pain than DES patients (P < 0.05). We
concluded that SSA was an effec-tive alternative to DES for
outpatient gynecological laparoscopy. IMPLICATIONS: This study
compared the use of a desflurane general anesthetic to a small-dose
spinal anesthetic in ambulatory gynecological laparoscopy.
Using the spinal technique, patients can walk from the operating
room table to a stretcher on completion of surgery. Their
recovery time was similar to that of the desflurane group.
PMID: 11812696
Anesth Analg 2002 Feb;94(2):325-330
The Inhibition of the N-Methyl-D-Aspartate Receptor Channel
by Local Anesthetics in Mouse CA1 Pyramidal Neurons.
Nishizawa N, Shirasaki T, Nakao S, Matsuda H, Shingu K
Departments of Anesthesiology and Physiology, Kansai Medical
University, Moriguchi-City, Osaka, Japan.
[Record supplied by publisher]
Although the effects of local anesthetics on sodium channels
and various other channels and receptors have been intensively
investigated, there is little information available about
their effects on N-methyl-D-aspartate (NMDA) receptors. We
examined the effects of four local anesthetics (procaine,
tetracaine, bupivacaine, and lidocaine) on NMDA-induced currents
by using a whole-cell patch-clamp technique in dissociated
mouse hippocampal pyramidal neurons. Procaine and tetracaine
produced a reversible and concentration-dependent inhibition
of NMDA-induced currents, but lidocaine showed little inhibition
at 1 mM or less. The half-maximal inhibition values (mM; mean
? SEM) for procaine, tetracaine, bupivacaine, and lidocaine
at -60 mV were 0.296 ? 0.031, 0.637 ? 0.044, 2.781 ? 0.940
(extrapolated data), and 7.766 ? 14.093 (extrapolated data),
respectively. Procaine 0.2 mM reduced the maximal NMDA-induced
currents without affecting the 50% effective concentration
values for NMDA. The inhibition by procaine exhibited voltage
dependence and was more effective at negative potentials.
These results indicate a noncompetitive antagonism of procaine
on NMDA receptors and suggest that the inhibition is the result
of a channel-blocking mechanism. IMPLICATIONS: We examined
the effects of four local anesthetics (procaine, tetracaine,
bupivacaine, and lidocaine) on NMDA-induced currents by using
a whole-cell patch-clamp technique in dissociated mouse hippocampal
pyramidal neurons. Both procaine and tetracaine produced a
reversible and concentration-dependent inhibition of the NMDA-induced
currents.
PMID: 11812692
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Anesth Analg 2002 Feb;94(2):319-24
The neurotoxicity of local anesthetics on growing neurons:
a comparative study of lidocaine, bupivacaine, mepivacaine,
and ropivacaine.
Radwan IA, Saito S, Goto F
Department of Anesthesiology & Reanimatology, Gunma University
School of Medicine, Gunma, Japan.
[Medline record in process]
Local anesthetics can be neurotoxic. To test the hypothesis
that exposure to local anesthetics produces morphological
changes in growing neurons and to compare this neurotoxic
potential between different local anesthetics, we performed
in vitro cell biological experiments with isolated dorsal
root ganglion neurons from chick embryos. The effects of lidocaine,
bupivacaine, mepivacaine, and ropivacaine were examined microscopically
and quantitatively assessed using the growth cone collapse
assay. We observed that all local anesthetics produced growth
cone collapse and neurite degeneration. However, they showed
significant differences in the dose response. The IC(50) values
were approximately, 10(-2.8) M for lidocaine, 10(-2.6) M for
bupivacaine, 10(-1.6) M for mepivacaine, and 10(-2.5) M for
ropivacaine at 15 min exposure. Some reversibility was observed
after replacement of the media. At 20 h after washout, bupivacaine
and ropivacaine showed insignificant percentage growth cone
collapse in comparison to their control values whereas those
for lidocaine and mepivacaine were significantly higher than
the control values. Larger concentrations of the nerve growth
factor (NGF) did not improve this reversibility. In conclusion,
local anesthetics produced morphological changes in growing
neurons with significantly different IC(50). The reversibility
of these changes differed among the four drugs and was not
influenced by the NGF concentration. IMPLICATIONS: Local anesthetics
induce growth cone collapse and neurite degeneration in the
growing neurons. Mepivacaine was safer than lidocaine, bupivacaine,
and ropivacaine for the primary cultured chick neurons.
PMID: 11812691, UI: 21670859
Anesth Analg 2002 Feb;94(2):313-318
The Anesthetic Mechanism of Urethane: The Effects on Neurotransmitter-Gated
Ion Channels.
Hara K, Harris RA
Waggoner Center for Alcohol and Addiction Research and Institute
for Cellular and Molecular Biology, University of Texas at
Austin, Austin, Texas.
[Record supplied by publisher]
Urethane is widely used as an anesthetic for animal studies
because of its minimal effects on cardiovascular and respiratory
systems and maintenance of spinal reflexes. Despite its usefulness
in animal research, there are no reports concerning its molecular
actions. We designed this study to determine whether urethane
affects neurotransmitter-gated ion channels. We examined the
effects of urethane on recombinant ?-aminobutyric acid(A),
glycine, N-methyl-D-aspartate, ?-amino-3-hydroxy-5-methyl-4-isoxazole
propionic acid, and neuronal nicotinic acetylcholine receptors
expressed in Xenopus oocytes. Urethane potentiated the functions
of neuronal nicotinic acetylcholine, ?-aminobutyric acid(A),
and glycine receptors, and it inhibited N-methyl-D-aspartate
and ?-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid
receptors in a concentration-dependent manner. At concentrations
close to anesthetic 50% effective concentration, urethane
had modest effects on all channels tested, suggesting the
lack of a single predominant target for its action. This may
account for its usefulness as a veterinary anesthetic. However,
a large concentration of urethane exerts marked effects on
all channels. These findings not only give insight into the
molecular mechanism of anesthetics but also caution that neurophysiologic
measurements from animals anesthetized with urethane may be
complicated by the effects of urethane on multiple neurotransmitter
systems. Our results also suggest that small changes in multiple
receptor systems can produce anesthesia. IMPLICATIONS: Urethane
modestly affects multiple neurotransmitter systems at an anesthetic
concentration. Our findings suggest that these degenerate
effects of urethane can produce anesthesia and that urethane
has a potential to influence neuronal measurements made in
in vivo preparations.
PMID: 11812690
Anesth Analg 2002 Feb;94(2):302-309
Transesophageal Echocardiography Interpretation: A Comparative
Analysis Between Cardiac Anesthesiologists and Primary Echocardiographers.
Mathew JP, Fontes ML, Garwood S, Davis E, White WD, McCloskey
G, Fitch JC, Afifi S, Lee DL, Kraker P, Rafferty TD, Barash
PG, Gillam L, Prokop E
Department of Anesthesiology, Duke University Medical Center,
Durham, North Carolina and Yale University School of Medicine,
New Haven, Connecticut.
[Record supplied by publisher]
Diagnostic interpretation of intraoperative transesophageal
echocardiography (TEE) examinations may vary, particularly
when the echocardiographer is also the anesthesiologist. We
therefore evaluated the concordance of TEE interpretation
as part of a process of continuous quality improvement (CQI).
Ten cardiac anesthesiologists participating in a CQI program
conducted 154 comprehensive TEE examinations, each consisting
of 16 major fields describing cardiac anatomy and function.
These examinations were subsequently interpreted off-line
by two primary echocardiographers (a radiologist and a cardiologist).
Agreement was assessed using the ? coefficient and percent
agreement. Overall ? and percent agreement were 0.58 and 83%
for anesthesiologists versus radiologist, 0.57 and 80% for
anesthesiologists versus cardiologist, and 0.60 and 82% for
radiologist versus cardiologist. Anesthesiologists with longer
than 5 yr of TEE experience had higher levels of agreement
with the radiologist when assessing the aorta, right atrium,
pulmonary vein flow, transmitral flow, and fractional area
change. Cardiac anesthesiologists supported by a CQI program
interpret TEE examinations at a level comparable with physicians
whose primary practice is echocardiography. Thus, the anesthesiologist
and the intraoperative echocardiographer need not be mutually
exclusive. IMPLICATIONS: Interpretation of intraoperative
transesophageal echocardiograms can be reliably performed
by cardiac anesthesiologists.
PMID: 11812688
Anesth Analg 2002 Feb;94(2):275-282
Thoracic Epidural Anesthesia for Cardiac Surgery: The Effects
on Tracheal Intubation Time and Length of Hospital Stay.
Departments of Anaesthesia, Cardiothoracic Surgery, and Cardiology,
Westmead Hospital, Westmead, Australia.
[Record supplied by publisher]
Improvements in analgesia after major surgery may allow a
more rapid recovery and shorter hospital stay. We performed
a prospective randomized trial to study the effects of epidural
analgesia on the length of hospital stay after coronary artery
surgery. The anesthetic technique and postoperative mobilization
were altered to facilitate early intensive care discharge
and hospital discharge. Fifty patients received high (T1 to
T4) thoracic epidural anesthesia (TEA) with ropivacaine 1%
(4-mL bolus, 3?5 mL/h infusion), with fentanyl (100-?g bolus,
15?25 ?g/h infusion) and a propofol infusion (6 mg . kg(-1)
. h(-1)). Another 50 patients (the General Anesthesia group)
received fentanyl 15 ?g/kg and propofol (5 mg . kg(-1) . h(-1)),
followed by IV morphine patient-controlled analgesia. The
TEA group had lower visual analog scores with coughing postextubation
(median, 0 vs 26 mm; P < 0.0001) and were extubated earlier
(median hours [interquartile range], 3.2 [2.1?4.6] vs 6.7
[3.3?13.2]; P < 0.0001). More than half of all patients
were discharged home on Postoperative Day 4 (24%) or 5 (33%),
but there was no difference in the length of stay between
the TEA group (median [interquartile range], Day 5 [5?6])
and the General Anesthesia group (median [interquartile range],
Day 5 [4?7]). There were no differences in postoperative spirometry
or chest radiograph changes or in markers for postoperative
myocardial ischemia or infarction. No significant TEA-related
complications occurred. In summary, TEA provided better analgesia
and allowed earlier tracheal extubation but did not reduce
the length of hospital stay after coronary artery surgery.
IMPLICATIONS: We found that epidural analgesia was more effective
than IV morphine for cardiac surgery. Epidural anesthesia
also allowed earlier weaning from mechanical ventilation,
but it did not affect hospital discharge time.
PMID: 11812684
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Anesth Analg 2002 Feb;94(2):271-4
Anesthesia for patients with congenital insensitivity to
pain and anhidrosis: a questionnaire study in Japan.
Tomioka T, Awaya Y, Nihei K, Sekiyama H, Sawamura S, Hanaoka
K
Department of Anesthesiology, Faculty of Medicine, The University
of Tokyo.
[Medline record in process]
We investigated the anesthetic management of patients with
congenital insensitivity to pain and anhidrosis (CIPA) in
Japan. CIPA is a rare inherited disease characterized by a
lack of pain sensation and thermoregulation. Although lacking
pain sensation, some patients do have tactile hyperesthesia.
Thus, anesthetics are a necessity during operations. We also
determined that because patients with CIPA have problems with
thermoregulation, temperature management is a concern during
the perioperative period and sufficient sedation is necessary
to avoid accidental fractures. Additionally, it was found
that the use of muscle relaxants does not present a problem,
malignant hyperthermia is not associated with CIPA, and that
the possibility of abnormalities in the autonomic nervous
system must be taken into consideration. Therefore, patients
with CIPA can be safely managed with anesthesia. IMPLICATIONS:
We investigated the anesthetic management of patients with
congenital insensitivity to pain and anhidrosis. We clarified
the following three important points: anesthesia is necessary,
temperature management must be maintained, and there must
be sufficient perioperative sedation in the anesthetic management
of patients with congenital insensitivity to pain and anhidrosis.
PMID: 11812683, UI: 21670851
Anesth Analg 2002 Feb;94(2):243-249
Autoantibodies Associated with Volatile Anesthetic Hepatitis
Found in the Sera of a Large Cohort of Pediatric Anesthesiologists.
Njoku DB, Greenberg RS, Bourdi M, Borkowf CB, Dake EM, Martin
JL, Pohl LR
Departments of Anesthesiology and Critical Care Medicine
and Pediatrics, The Johns Hopkins Medical Institutions, Baltimore,
Maryland, the Molecular and Cellular Toxicology Section of
the Laboratory of Molecular Immunology, and the Division of
Epidemiology and Clinical Applications, Office of Biostatistics
Research, National Heart, Lung, and Blood Institute, National
Institutes of Health, Bethesda, Maryland.
[Record supplied by publisher]
Anesthetic-induced hepatitis is thought to have an immune-mediated
basis, in part because many patients who develop hepatitis
have serum autoantibodies that react with specific hepatic
proteins. The present study shows that pediatric anesthesiologists
also have these serum autoantibodies. Moreover, levels of
these autoantibodies are higher than those of general anesthesiologists.
We collected sera from 105 pediatric and 53 general anesthesiologists
(including 3 nurse anesthetists), 20 halothane hepatitis patients,
and 20 control individuals who were never exposed to inhaled
anesthetics. Serum cytochrome P450 2E1 (P450 2E1) and 58-kd
hepatic endoplasmic reticulum protein (ERp58) autoantibodies
were measured by enzyme-linked immunosorbent assays. Positive
values were 2 SD above median control values. Two multiple
regression models were constructed. Pediatric anesthesiologists,
like halothane hepatitis patients, had higher serum autoantibody
levels of ERp58 and P450 2E1 than general anesthesiologists
and controls, which was possibly because of their increased
occupational exposures to anesthetics. Female anesthesiologists
had higher levels of ERp58 autoantibodies than male anesthesiologists,
whereas female pediatric anesthesiologists had higher levels
of P450 2E1 autoantibodies than all other anesthesiologists.
One female pediatric anesthesiologist had symptoms of hepatic
injury. Because most anesthesiologists do not develop volatile
anesthetic-induced hepatic injury, the findings suggest that
pathogenic ERp58 and P450 2E1 autoantibodies may not directly
cause volatile anesthetic hepatitis. Female anesthesiologists
have high levels of these autoantibodies; however, the majority
of these individuals do not develop hepatitis, suggesting
that autoantibodies may not have a pathological role in volatile
anesthetic-induced hepatitis. IMPLICATIONS: Environmental
exposure of anesthesiology personnel to certain inhaled anesthetics
can induce the formation of autoantibodies that have been
associated with anesthetic hepatitis. Female anesthesiologists
have high levels of these autoantibodies; however, the majority
of these individuals do not develop hepatitis, suggesting
that autoantibodies may not have a pathological role in volatile
anesthetic-induced hepatitis.
PMID: 11812677
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Anesth Analg 2002 Jan;94(1):235
Capnography and severe COPD.
Broka SM, Boujlel S
Publication Types:
Letter
PMID: 11772840, UI: 21633757
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Anesth Analg 2002 Jan;94(1):233-4
Is it ethically correct to study the Quincke spinal needle
in obstetric patients?
Heard CM, Fletcher JE
Publication Types:
Letter
PMID: 11772837, UI: 21633754
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Anesth Analg 2002 Jan;94(1):231-2, table of contents
Difficult endotracheal intubation as a result of penetrating
cranio-facial injury by an arrow.
Joly LM, Oswald AM, Disdet M, Raggueneau JL
Departement d'Anesthesie-Reanimation, Centre Hospitalier
Sainte Anne, 75674 Paris Cedex 14, France. joly@chsa.broca.inserm.fr
Penetrating injury of the face and airway may make endotracheal
intubation difficult or impossible. We report the case of
a patient who attempted to commit suicide with a crossbow.
Surgery under general anesthesia was required to remove the
arrow. The oral intubation route was impossible, and a fiberoptic
nasal intubation under local anesthesia was performed. IMPLICATIONS:We
report a case of a 42-yr-old patient who underwent surgery
for a penetrating craniofacial injury caused by an arrow.
Because of the median vertical trajectory of the arrow (from
the chin to the frontal skull), only the right nasal approach
was accessible for endotracheal intubation. Fiberoptic nasal
intubation and securing the airway under local anesthesia
are described.
PMID: 11772835, UI: 21633752
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Anesth Analg 2002 Jan;94(1):227-30, table of contents
Alkalinization of intracuff lidocaine improves endotracheal
tube-induced emergence phenomena.
Estebe JP, Dollo G, Le Corre P, Le Naoures A, Chevanne F,
Le Verge R, Ecoffey C
Service d'Anesthesie Reanimation Chirurgicale 2 , Universite
de Rennes, Rennes, France. jean-pierre.estebe@chu-rennes.fr
We sought to evaluate the effect of filling an endotracheal
tube cuff with 40 mg lidocaine alone (Group L) or alkalinized
lidocaine (Group LB) in comparison to an Air Control group
(Group C) on adverse emergence phenomena in a randomized controlled
study (n = 25 in each group). The incidence of sore throat
was decreased for Group LB in comparison to Group L during
the 24 postextubation hours. The difference between Group
L and Group C remained significant in the two postextubation
hours only. Plasma lidocaine levels increased when lidocaine
was alkalinized (C(max) were 62.5 +/- 34.0 ng/mL and 3.2 +/-
1.0 ng/mL for Groups LB and L, respectively). Cough and restlessness
before tracheal extubation were decreased in Group LB compared
with Group L and in Group L compared with Group C. Nausea,
postoperative vomiting, dysphonia, and hoarseness were increased
after extubation in Group C compared with the liquid groups,
and a better tolerance was recorded with Group LB compared
with Group L. The increase of arterial blood pressure and
cardiac frequencies during the extubation period was less
in the liquid groups than in the control group and less in
Group LB compared with Group L. We concluded that use of intracuff
alkalinized lidocaine is an effective adjunct to endotracheal
intubation. IMPLICATIONS: Use of 40 mg of alkalinized lidocaine,
rather than lidocaine or air, to fill the endotracheal tube
cuff reduces the incidence of sore throat in the postoperative
period. This approach also decreases hemodynamic effects,
restlessness, dysphonia, and hoarseness.
Publication Types:
Clinical trial
Randomized controlled trial
PMID: 11772834, UI: 21633751
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Anesth Analg 2002 Jan;94(1):221-6, table of contents
Thermoregulatory response to intraoperative head-down tilt.
Nakajima Y, Mizobe T, Matsukawa T, Sessler DI, Kitamura
Y, Tanaka Y
Department of Anesthesiology, Kyoto Prefectural University
of Medicine, Kyoto, Japan.
Thermoregulation interacts with cardiovascular regulation
within the central nervous system. We therefore evaluated
the effects of head-down tilt on intraoperative thermal and
cardiovascular regulation. Thirty-two patients undergoing
lower-abdominal surgery were randomly assigned to the 1) supine,
2) 15 degrees -20 degrees head-down tilt, 3) leg-up, or 4)
combination of leg-up and head-down tilt position. Core temperature
and forearm minus fingertip skin-temperature gradients (an
index of peripheral vasoconstriction) were monitored for 3
h after the induction of combined general and lumbar epidural
anesthesia. We also determined cardiac output and central-venous
and esophageal pressures. Neither right atrial transmural
pressure nor cardiac index was altered in the Head-Down Tilt
group, but both increased significantly in the Leg-Up groups.
The vasoconstriction threshold was reduced in both leg-up
positions but was not significantly decreased by head-down
tilt. Final core temperatures were 35.2 degrees C +/- 0.2
degrees C (mean +/- SEM) in the Supine group, 35.0 degrees
C +/- 0.2 degrees C in the Head-Down Tilt group, 34.2 degrees
C +/- 0.2 degrees C in the Leg-Up group (P < 0.05 compared
with supine), and 34.3 degrees C +/- 0.2 degrees C when leg-up
and head-down tilt were combined (P < 0.05 compared with
supine). These results confirm that elevating the legs increases
right atrial transmural pressure, reduces the vasoconstriction
threshold, and aggravates intraoperative hypothermia. Surprisingly,
maintaining a head-down tilt did not increase right atrial
pressure. IMPLICATIONS: Intraoperative hypothermia is exaggerated
when patients are maintained in the leg-up position because
the vasoconstriction threshold is reduced. However, head-down
tilt (Trendelenburg position) does not reduce the vasoconstriction
threshold or aggravate hypothermia. The head-down tilt position
thus does not require special perioperative thermal precautions
or management unless the leg-up position is used simultaneously.
Publication Types:
Clinical trial
Randomized controlled trial
PMID: 11772833, UI: 21633750
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Anesth Analg 2002 Jan;94(1):213-4, table of contents
Transient neurological symptoms after subarachnoid meperidine.
Lewis WR, Perrino AC Jr
Department of Anesthesiology, VA Connecticut Healthcare System,
West Haven, Connecticut 06516, USA. Wilfred.Lewis@med.va.gov
IMPLICATIONS: The syndrome of transient neurological symptoms
(TNS) after subarachnoid use of local anesthetics, particularly
lidocaine, has been well described. This syndrome has not
been reported with the subarachnoid use of opioids. This case
report describes TNS that occurred after administration of
subarachnoid meperidine, an opioid with local anesthetic properties.
PMID: 11772831, UI: 21633748
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Anesth Analg 2002 Jan;94(1):188-93, table of contents
Hyperbaric spinal levobupivacaine: a comparison to racemic
bupivacaine in volunteers.
Alley EA, Kopacz DJ, McDonald SB, Liu SS
Department of Anesthesiology, Virginia Mason Medical Center,
Seattle, Washington 98111, USA.
Levobupivacaine is the isolated S-enantiomer of bupivacaine
and may be a favorable alternative to spinal bupivacaine.
However, its clinical efficacy relative to bupivacaine and
its dose-response characteristics, in spinal anesthesia, must
first be known. This double-blinded, randomized, cross-over
study was designed to compare the clinical efficacy of hyperbaric
levobupivacaine and bupivacaine for spinal anesthesia. Eighteen
healthy volunteers were randomized into three equal groups
to receive two spinal anesthetics, one with bupivacaine and
the other with levobupivacaine, of equal-milligram doses (4,
8, or 12 mg). We assessed blockade quality and duration with
pinprick, transcutaneous electrical stimulation, thigh tourniquet,
abdominal and quadriceps muscle strength, modified Bromage
scale, and time until achievement of discharge criteria. Sensory
and motor block were similar between the same doses of levobupivacaine
and bupivacaine (P > 0.56 to 0.86). For example, in the
12-mg groups of levobupivacaine versus bupivacaine, mean duration
of tolerance to transcutaneous electrical stimulation at T12
was 100 min for both. The duration of motor block at the quadriceps
was 71 versus 73 min, and time until achievement of discharge
criteria was 164 min for both. Hyperbaric spinal levobupivacaine
has equivalent clinical efficacy to racemic bupivacaine for
spinal anesthesia in doses from 4 to 12 mg. IMPLICATIONS:
Hyperbaric spinal levobupivacaine has equivalent clinical
efficacy to hyperbaric spinal bupivacaine over the 4-12-mg
ranges.
Publication Types:
Clinical trial
Randomized controlled trial
PMID: 11772826, UI: 21633743
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Anesth Analg 2002 Jan;94(1):123-4, table of contents
Prolongation of rapacuronium neuromuscular blockade by clindamycin
and magnesium.
Sloan PA, Rasul M
University of Kentucky College of Medicine, Lexington, Kentucky
40536, USA. PaulSloan@prodigy.net
IMPLICATIONS: We report a prolonged neuromuscular block with
the nondepolarizing muscle relaxant rapacuronium in the presence
of clindamycin. Even when using "short-acting" muscle
relaxants, the anesthesiologist must routinely monitor the
neuromuscular function.
PMID: 11772813, UI: 21633730
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Anesth Analg 2002 Jan;94(1):106-11, table of contents
Dolasetron for preventing postanesthetic shivering.
Department of Anesthesiology and Critical Care Medicine,
Klinikum Ludwigshafen, Ludwigshafen, Germany.
We designed this study to assess the efficacy of dolasetron
compared with clonidine and placebo in prophylaxis of postanesthetic
shivering. We included 90 patients undergoing elective abdominal
or urologic surgery. The patients were randomly assigned to
one three groups (each group n = 30) using a double-blinded
study protocol: Group A received 12.5 mg dolasetron, Group
B 3 microg/kg clonidine, and Group C saline 0.9% as placebo.
The medication was given after the induction of anesthesia.
Postanesthetic shivering was judged by using a five-point
scale. In the Clonidine group, 86.6% showed no shivering,
whereas in the Dolasetron and Placebo groups, only 63.3% and
66.6%, respectively, were symptom free. Only clonidine, but
not dolasetron, significantly reduced the incidence and the
severity of shivering. We conclude that clonidine is effective
in preventing shivering when given before surgery, whereas
dolasetron, at the dose used, is not effective. IMPLICATIONS:
Shivering, an irregular muscular fasciculation lasting longer
than 15 s, is a common complication secondary to general anesthesia.
We compared dolasetron with clonidine (an established antishivering
drug) in the prevention of postanesthetic shivering. Dolasetron
12.5 mg was not effective.
Publication Types:
Clinical trial
Randomized controlled trial
PMID: 11772810, UI: 21633727
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Anesth Analg 2002 Jan;94(1):65-70, table of contents
Ambulatory discharge after long-acting peripheral nerve
blockade: 2382 blocks with ropivacaine.
Klein SM, Nielsen KC, Greengrass RA, Warner DS, Martin A,
Steele SM
Department of Anesthesiology, Duke University Medical Center,
Durham, North Carolina 27710, USA. klein006@mc.duke.edu
Discharging patients with a long-acting peripheral nerve
block remains controversial. Concerns about accidental injury
of the limb or surgical site because of an insensate extremity
are common despite a lack of data on the subject. We report
a study examining the efficacy and complications of discharge
after long-acting block. This prospective study included 1791
patients receiving an upper or lower extremity nerve block
with 0.5% ropivacaine and discharged the day of surgery. Efficacy
(conversion to general anesthesia and opioid use), persistent
motor or sensory weakness, complications, satisfaction, and
unscheduled health care visits were assessed in the postanesthesia
care unit (PACU) and at 24 h and 7 days postoperatively using
a detailed questionnaire. There were 2382 blocks placed: 1119
upper extremity blocks and 1263 lower extremity blocks. Efficacy
was demonstrated by a small conversion to general anesthesia
(1%-6%) and a lack of patients requiring opioids in the PACU
(89%-92%). A large percentage of patients continued to use
opioids at 7 days (17%-22%). Despite the requirement for opioids,
satisfaction with the anesthesia experience was high at 24
h and 7 days (Liekert scale [1-5] mean at 24 h, 4.88 +/- 0.44;
mean at 7 days, 4.77 +/- 0.69) and most (98%) would choose
the same anesthetic again. Thirty-seven patients (1.6%) were
identified with symptoms or complaints at 7 days. After review,
6 of them (0.25%) had a persistent paresthesia that may have
been related to the block or discharge. We conclude that long-acting
peripheral nerve blockade may be safely used in the ambulatory
setting with a high degree of efficacy, safety, and satisfaction.
This technique is associated with an infrequent incidence
of neurologic complications and injuries. Given the frequent
incidence of persistent pain at 7 days, prolongation of the
analgesia would be beneficial. IMPLICATIONS: This study demonstrates
that long-acting peripheral nerve blockade may be safely used
in the ambulatory setting with a high degree of efficacy and
satisfaction. This technique is associated with an infrequent
incidence of neurologic complications and injuries despite
discharge with an insensate extremity. The frequent incidence
of pain at 7 days suggests that longer-acting local anesthetics
are still needed.
PMID: 11772802, UI: 21633719
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Anesth Analg 2002 Jan;94(1):44-9, table of contents
The pharmacokinetics of epsilon-aminocaproic acid in children
undergoing surgical repair of congenital heart defects.
Ririe DG, James RL, O'Brien JJ, Lin YA, Bennett J, Barclay
D, Hines MH, Butterworth JF
Department of Anesthesiology, Wake Forest University School
of Medicine, Winston-Salem, North Carolina 27157-1009, USA.
dririe@wfubmc.edu
epsilon-Aminocaproic acid (epsilonACA) is often administered
to children undergoing cardiac surgery by using empiric dosing
techniques. We hypothesized that children would have different
pharmacokinetic variables and require a dosing scheme different
from adults to maintain stable and effective serum epsilonACA
concentrations. Eight patients were enrolled in our study.
epsilonACA 50 mg/kg was administered three times IV: before,
during, and after cardiopulmonary bypass (CPB). Nine serum
samples were obtained. epsilonACA plasma concentrations were
measured by using high-performance liquid chromatography,
and pharmacokinetic modeling was done by using NONMEM. The
best fit was seen with a two-compartment model with volume
of distribution (V(1)) adjusted for weight and CPB. Compared
with published results in adults, modeling suggests that weight-adjusted
V(1) is larger in children than in adults before, during,
and after CPB. Clearance from the central compartment (k(10))
was also greater in children than adults, and declined during
CPB. Redistribution rates from the central compartment, k(12)
and k(21), were greater in children and not affected by CPB.
We modeled several different dosing regimens for epsilonACA
based on the larger V(1), and higher redistribution and clearance
variables. We conclude that, because of the developmental
differences in pharmacokinetic variables of epsilonACA, when
compared with adult patients, a larger initial dose and faster
infusion rate as well as an addi-tional dose on CPB are needed
to maintain similar concentrations. IMPLICATIONS: Pharmacokinetic
modeling of epsilon-aminocaproic acid in children undergoing
cardiac surgery suggests that there are developmental differences
in pharmacokinetic variables. Based on these data, a dosing
modification in children is suggested which may better maintain
serum concentrations in children when compared with adults.
PMID: 11772798, UI: 21633715
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Anesth Analg 2002 Jan;94(1):31-6, table of contents
Oral midazolam premedication in preadolescents and adolescents.
Brosius KK, Bannister CF
Department of Anesthesiology, Emory University School of
Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia,
USA.
We sought to determine the influence of preoperative oral
midazolam on 1) sedation score, 2) measures of anesthetic
emergence, 3) recovery times, and 4) bispectral index (BIS)
measurements during sevoflurane/N(2)O anesthesia in adolescent
patients. Fifty ASA I and II patients 10-18 yr of age were
enrolled in a prospective double-blinded study. Patients were
randomized to receive either 20 mg of midazolam (M group)
or midazolam vehicle (P group) as premedication. Before the
induction, sedation scores and BIS values were determined
in all patients. After inhaled induction and intubation, expired
sevoflurane was stabilized at 3% in 60% N(2)O and the corresponding
BIS (BIS I) recorded. Upon completion of surgery, sevoflurane
was stabilized at 0.5% and the BIS (BIS E) again recorded.
Plasma midazolam levels were measured at the time of BIS I
and BIS E. There were no significant differences between groups
in awakening time, sevoflurane/N(2)O awakening concentrations,
time to postanesthesia care unit discharge, or BIS I and BIS
E measurements. Sedation scores and preinduction BIS values
were significantly lower in Group M than in Group P, although
only 40% of midazolam-treated patients exhibited detectable
sedation, with marked interindividual variability in achieved
plasma midazolam levels. Detectable preoperative sedation
was predictive of delayed emergence. IMPLICATIONS: We demonstrated
a measurable sedative effect of oral midazolam in adolescents
which correlated with simultaneous bispectral index (BIS)
measurement. Considering the overall group, midazolam premedication
did not affect intraoperative BIS, emergence times, or recovery
times compared with placebo controls. Detectable preoperative
sedation, and not merely midazolam administration, was predictive
of prolonged emergence.
Publication Types:
Clinical trial
Randomized controlled trial
PMID: 11772796, UI: 21633713
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Anesthesiology 2002 Feb;96(2):515
High Incidence of Cardiac Arrest following Spinal Anesthesia.
Pollard JB
[Medline record in process]
PMID: 11818793, UI: 21676126
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Anesthesiology 2002 Feb;96(2):508-9
Brain Tumor Presenting with Fatal Herniation following Delivery
under Epidural Anesthesia.
Su TM, Lan CM, Yang LC, Lee TC, Wang KW, Hung KS
Department of Neurosurgery, Chang Gung Memorial Hospital,
Kaohsiung, Taiwan.
[Medline record in process]
PMID: 11818788, UI: 21676121
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Anesthesiology 2002 Feb;96(2):497-503
Anesthetic management of deep hypothermic circulatory arrest
for cerebral aneurysm clipping.
Young WL, Lawton MT, Gupta DK, Hashimoto T
Departments of Anesthesia and Perioperative Care, Neurological
Surgery, and Neurology, and the Center for Cerebrovascular
Research, University of California, San Francisco, San Francisco,
California.
[Medline record in process]
PMID: 11818785, UI: 21676118
Anesthesiology 2002 Feb;96(2):485-496
Practice Advisory for Preanesthesia Evaluation: A Report
by the American Society of Anesthesiologists Task Force on
Preanesthesia Evaluation.
[Record supplied by publisher]
PMID: 11818784
Anesthesiology 2002 Feb;96(2):458-466
Inhibitory Effects of Volatile Anesthetics on K+ and Cl?
Channel Currents in Porcine Tracheal and Bronchial Smooth
Muscle.
Chen X, Yamakage M, Namiki A
Department of Anesthesiology, Sapporo Medical University
School of Medicine, Sapporo, Hokkaido, Japan.
[Record supplied by publisher]
BACKGROUND: K+ and Ca2+-activated Cl? (ClCa) channel currents
have been shown to contribute to the alteration of membrane
electrical activity in airway smooth muscle. This study was
conducted to investigate the effects of volatile anesthetics,
which are potent bronchodilators, on the activities of these
channels in porcine tracheal and bronchial smooth muscles.
METHODS: Whole-cell patch clamp recording techniques were
used to investigate the effects of superfused isoflurane (0?1.5
minimum alveolar concentration) or sevoflurane (0?1.5 minimum
alveolar concentration) on K+ and ClCa channel currents in
dispersed smooth muscle cells. RESULTS: Isoflurane and sevoflurane
inhibited whole-cell K+ currents to a greater degree in tracheal
versus bronchial smooth muscle cells. More than 60% of the
total K+ currents in tracheal smooth muscle appeared to be
mediated through delayed rectifier K+ channels compared with
less than 40% in bronchial smooth muscle. The inhibitory effects
of the anesthetics were greater on the delayed rectifier K+
channels than on the remaining K+ channels. Cl? currents through
ClCa channels were significantly inhibited by the anesthetics.
The inhibitory potencies of the anesthetics on the ClCa channels
were not different in tracheal and bronchial smooth muscle
cells. CONCLUSIONS: Volatile anesthetics isoflurane and sevoflurane
significantly inhibited Cl? currents through ClCa channels,
and the inhibitory effect is consistent with the relaxant
effect of volatile anesthetics in airway smooth muscle. Different
distributions and different anesthetic sensitivities of K+
channel subtypes could play a role in the different inhibitory
effects of the anesthetics on tracheal and bronchial smooth
muscle contractions.
PMID: 11818782
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Anesthesiology 2002 Feb;96(2):442-9
Volume Kinetic Analysis of the Distribution of 0.9% Saline
in Conscious versus Isoflurane-anesthetized Sheep.
Brauer KI, Svensen C, Hahn RG, Traber LD, Prough DS
Department of Anesthesiology, The University of Texas Medical
Branch, Galveston, Texas.
[Medline record in process]
BACKGROUND: The distribution and elimination of 0.9% saline
given by intravenous infusion has not been compared between
the conscious state and during inhalational anesthesia. METHODS:
Six adult sheep received an intravenous infusion of 25 ml/kg
of 0.9% saline over 20 min in the conscious state and also
during isoflurane anesthesia and mechanical ventilation. The
distribution and elimination of infused fluid were studied
by volume kinetics based on serial analysis of hemoglobin
dilution in arterial blood and by mass balance that incorporated
volume calculations derived from volume kinetic analysis and
measurements of urinary volumes. RESULTS: The mass balance
calculations indicated only minor differences in the time
course of plasma volume expansion between the conscious and
anesthetized states. However, isoflurane anesthesia markedly
reduced urinary volume (median, 9 vs. 863 ml; P < 0.03).
In conscious sheep, the central and peripheral volume expansion
predicted by volume kinetics agreed well with the calculations
based on mass balance. However, during isoflurane anesthesia
and mechanical ventilation, calculation using volume kinetic
analysis of the variable kr, an elimination factor that, in
conscious humans and sheep, is closely related to urinary
excretion, represented both urinary excretion and peripheral
accumulation of fluid. This suggests that the previous assumption
that kr approximates urinary excretion of infused fluid requires
modification, i.e., kr simply reflects net fluid movement
out of plasma. CONCLUSIONS: In both conscious and anesthetized,
mechanically ventilated sheep, infusion of 0.9% saline resulted
in minimal expansion of plasma volume over a 3-h interval.
In conscious sheep, infused 0.9% saline was rapidly eliminated
from the plasma volume by urinary excretion; in contrast,
the combination of isoflurane anesthesia and mechanical ventilation
reduced urinary excretion and promoted peripheral accumulation
of fluid.
PMID: 11818780, UI: 21676113
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Anesthesiology 2002 Feb;96(2):400-8
Efficient Trial Design for Eliciting a Pharmacokinetic-
Pharmacodynamic Model-based Response Surface Describing the
Interaction between Two Intravenous Anesthetic Drugs.
Short TG, Ho TY, Minto CF, Schnider TW, Shafer SL
Palo Alto Veterans Administration Health Care Center, Palo
Alto, California.
[Medline record in process]
BACKGROUND: The authors published a pharmacokinetic- pharmacodynamic
model for two drugs based on response surface methodology.
Because of the complexity of the model, they performed a simulation
study to answer two questions about use of the model: (1)
which study design would be most satisfactory; and (2) how
many patients would need to be studied to adequately describe
an entire response surface. METHODS: Data were simulated using
realistic variability for two hypothetical intravenous anesthetic
drugs that interact synergistically and that could be given
by computer-controlled infusion. Three trial designs were
simulated, one that made a series of parallel slices of the
response surface, one that crisscrossed the response surface,
and one that made a series of radial slices across the surface.
Series of 5, 10, 20, and 40 "subjects" were simulated.
A pooled data approach was used to assess the ability of the
various trial designs and numbers of subjects to adequately
identify the interaction response surface and estimate the
original response surface. RESULTS: The crisscross design
was shown to be the most robust in terms of its ability to
both discriminate the correct order of the interaction term
and to discriminate the original response surface using the
least number of patients. Twenty subjects would be required
to adequately define a surface using the crisscross study
design, and 40 subjects would be required using the other
trial designs. CONCLUSIONS: The results showed that a number
of trial designs would be viable, but a design that crossed
the surface in a crisscross fashion would give the most robust
result with the least patients.
PMID: 11818774, UI: 21676107
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Anesthesiology 2002 Feb;96(2):306-12
Transcutaneous electrical stimulation of an auricular acupuncture
point decreases anesthetic requirement.
Greif R, Laciny S, Mokhtarani M, Doufas AG, Bakhshandeh
M, Dorfer L, Sessler DI
Department of Anesthesia and Perioperative Care, University
of California-San Francisco, San Francisco, California.
[Medline record in process]
BACKGROUND: German anesthesiologists have long used transcutaneous
electrical stimulation of an acupuncture point near the tragus
to reduce anesthetic requirement in unblinded and uncontrolled
trials. This is known as auricular electrically stimulated
analgesia. The authors therefore tested the hypothesis that
auricular electrically stimulated analgesia reduces anesthetic
requirement. METHODS: In a randomized, double-blind, crossover
trial, volunteers were anesthetized twice with desflurane.
Electrical stimulation of an auricular acupuncture point in
the vicinity of the tragus was used on 1 randomly assigned
day, and no electrical stimulation of the same point was used
on the other study day. Treatment consisted of bilateral electrical
stimulation of the lateralization control point, 3 cm anterior
to the tragus. The 10-mA current was set to 299 Hz on the
dominant side of the face and to 149 Hz on the contralateral
side. Anesthetic requirement was determined by the Dixon up-and-down
method and was defined by the average desflurane concentration
required to prevent purposeful movement of the extremities
in response to noxious electrical stimulation. RESULTS: Ten
men and 10 women completed the protocol. Electrical stimulation
of the lateralization control point reduced anesthetic requirement
by 11 +/- 7% (P < 0.001), with the reduction being similar
in women and men. Women required more desflurane to prevent
movement on the control day than the men (5.5 +/- 1.0 vs.
4.6 +/- 0.6 vol%; P = 0.028). CONCLUSION: This double-blinded
trial with an objective outcome demonstrates that electrical
stimulation of the lateralization control point significantly
reduces anesthetic requirement.
PMID: 11818761, UI: 21676094
Anesthesiology 2002 Feb;96(2):289-295
A Multicenter Study Comparing the ProSealTM and ClassicTM
Laryngeal Mask Airway in Anesthetized, Nonparalyzed Patients.
Brimacombe J, Keller C, Fullekrug B, Agro F, Rosenblatt
W, Dierdorf SF, Garcia De Lucas E, Capdevilla X, Brimacombe
N
University of Queensland, Cairns Base Hospital, Cairns, Australia.
[Record supplied by publisher]
BACKGROUND: The laryngeal mask airway ProSeal? (PLMA?), a
new laryngeal mask device, was compared with the laryngeal
mask airway Classic? (LMA?) with respect to: (1) insertion
success rates and times; (2) efficacy of seal; (3) fiberoptically
determined anatomic position; (4) orogastric tube insertion
success rates and times; (5) total intraoperative complications;
and (6) postoperative sore throat in nonparalyzed adult patients
undergoing general anesthesia, hypothesizing that these would
be different. METHODS: Three hundred eighty-four nonparalyzed
anesthetized adult patients (American Society of Anesthesiologists
physical status I?II) were randomly allocated to the PLMA?
or LMA? for airway management. In addition, 50% of patients
were randomized for orogastric tube placement. Unblinded observers
collected intraoperative data, and blinded observers collected
postoperative data. RESULTS: First-attempt insertion success
rates (91 vs. 82%, P = 0.015) were higher for the LMA?, but
after three attempts success rates were similar (LMA?, 100%;
PLMA?, 98%). Less time was required to achieve an effective
airway with the LMA? (31 +/- 30 vs. 41 +/- 49 s; P = 0.02).
The PLMA? formed a more effective seal (27 +/- 7 vs. 22 +/-
6 cm H2O; P < 0.0001). Fiberoptically determined anatomic
position was better with the LMA? (P < 0.0001). Orogastric
tube insertion was more successful after two attempts (88
vs. 55%; P < 0.0001) and quicker (22 +/- 18 vs. 38 +/-
56 s) with the PLMA?. During maintenance, the PLMA? failed
twice (leak, stridor) and the LMA? failed once (laryngospasm).
Total intraoperative complications were similar for both groups.
The incidence of postoperative sore throat was similar. CONCLUSION:
In anesthetized, nonparalyzed patients, the LMA? is easier
and quicker to insert, but the PLMA? forms a better seal and
facilitates easier and quicker orogastric tube placement.
The incidence of total intraoperative complications and postoperative
sore throat are similar.
PMID: 11818758
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Anesthesiology 2002 Feb;96(2):261-3
Genetics infuses new life into human physiology: implications
of the human genome project for anesthesiology and perioperative
medicine.
Schwinn DA, Booth JV
[Medline record in process]
PMID: 11818753, UI: 21676086
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BMJ 2002 Jan 19;324(7330):170
Anaesthetic machines and anti-hypoxia devices. When is an
anti-hypoxia device not an anti-hypoxia device?
Pollock CG
[Medline record in process]
Publication Types:
Letter
PMID: 11822338, UI: 21680047
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BMJ 2002 Jan 19;324(7330):169-70
Anaesthetic machines and anti-hypoxia devices. Interim solution
is to remove nitrous oxide cylinders and pipelines and cap
their connections.
Fielden JM
[Medline record in process]
Publication Types:
Letter
PMID: 11822337, UI: 21680046
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Can J Anaesth 2002 Feb;49(2):215-6
Myasthenie et anesthesie pour chirurgie abdominale en urgence.
Anesthesia for urgent abdominal surgery and myasthenia gravis.
Devys JM, Debaene B, Plaud B
Paris, France Poitiers, France.
[Medline record in process]
PMID: 11823407, UI: 21681289
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Can J Anaesth 2002 Feb;49(2):207-9
Best evidence in anesthetic practice: Prevention: recombinant
human activated protein C reduces mortality in severe sepsis.
Butler R, Laufer B
London, Ontario Montreal, Quebec.
[Medline record in process]
PMID: 11823403, UI: 21681285
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Can J Anaesth 2002 Feb;49(2):194-7
Caudal anesthesia reduces the minimum alveolar concentration
of enflurane for laryngeal mask airway removal in boys : [L'anesthesie
caudale permet de reduire la concentration alveolaire minimale
d'enflurane pendant le retrait du masque larynge chez des
garcons].
Xiao WJ, Deng XM, Tang GZ, Lu MP, Xu KL
Department of Anesthesiology, Plastic Surgery Hospital, Chinese
Academy of Medical Sciences, Peking Union Medical College,
Beijing, China.
[Medline record in process]
PURPOSE: To investigate the effects of caudal analgesia on
the minimal alveolar concentration of enflurane for laryngeal
mask airway (LMA) smooth extubation (MACex). METHODS: We studied
50 nonpremedicated children, aged three to ten years, ASA
physical status I, undergoing surgery for hypospadias repair.
After a sevoflurane inhalation induction, children were randomized
to receive LMA insertion with or without ropivacaine caudal
analgesia. At the end of surgery, a predetermined end-tidal
enflurane concentration was achieved, and the LMA was removed
by an anesthesiologist blinded to group allocation. Each concentration
at which LMA extubation was attempted was predetermined by
the up-and-down method (with 0.1% as the step size). When
LMA removal was accomplished without coughing, clenching teeth
or gross purposeful muscular movements during or within one
minute after removal, it was considered successful. RESULTS:
MACex of enflurane for LMA removal in the group without caudal
anesthesia was 1.04% (95% confidence interval, 1.00-1.10)
and the LMA MACex of enflurane in the group with caudal anesthesia
was 0.74% (95% confidence interval, 0.63-0.81). Caudal analgesia
significantly reduced enflurane requirements by 29% (95% confidence
interval, 22-36%). CONCLUSION: In conclusion, caudal analgesia
significantly reduced the LMA MACex of enflurane by approximately
29%. Possible mechanisms may be related to the analgesic effect
of caudal blockade or to the sedative properties of neuraxial
anesthesia.
PMID: 11823400, UI: 21681282
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Can J Anaesth 2002 Feb;49(2):185-9
Baseline heart rate may predict hypotension after spinal
anesthesia in prehydrated obstetrical patients : [La frequence
cardiaque initiale peut etre predictive d'hypotension apres
la rachianesthesie chez des patientes obstetricales prehydratees].
Frolich MA, Caton D
Departments of Anesthesiology and Obstetrics and Gynecology,
University of Florida College of Medicine, Gainesville, Florida,
USA.
[Medline record in process]
PURPOSE: Hypotension is the most frequent complication of
spinal anesthesia in pregnant patients. This study was designed
to identify patients at risk for postspinal hypotension based
on preoperative vital signs before and after an orthostatic
challenge. METHODS: Forty healthy women scheduled for elective
Cesarean section were enrolled in this prospective trial.
Blood pressure (BP) and heart rate (HR) were recorded with
the patient in the lateral supine position and after standing
up. After a bupivacaine spinal anesthetic, BP was obtained
every two minutes for 30 min. Ephedrine treatment was administered
based on the degree of hypotension observed. Hemodynamic parameters
were correlated to ephedrine requirements (Spearman's rank
order correlation). RESULTS: There was a significant correlation
in baseline maternal HR and ephedrine requirements (P=0.005).
The degree of orthostatic changes in mean arterial BP and
HR did not correlate with postspinal hypotension. CONCLUSIONS:
Baseline HR may be predictive of obstetric spinal hypotension.
Higher baseline HR, possibly reflecting a higher sympathetic
tone, may be a useful parameter to predict postspinal hypotension.
PMID: 11823398, UI: 21681280
Can J Anaesth 2002 Feb;49(2):169-172
Central nervous system side effects are less important after
iv regional anesthesia with ropivacaine 0.2% compared to lidocaine
0.5% in volunteers: [Les effets secondaires neurologiques
sont moins importants apres une anesthesie regionale iv realisee
avec de la ropivacaine a 0,2 % comparee a la lidocaine a 0,5
%].
Atanassoff PG, Hartmannsgruber MW
Department of Anesthesiology Yale University School of Medicine
New Haven Connecticut USA.
[Record supplied by publisher]
PURPOSE: Following release of a double tourniquet for intravenous
regional anesthesia (IVRA), ropivacaine was shown to have
a longer duration of action and less central nervous system
(CNS) side effects than lidocaine. This study examines the
correlation of CNS side effects to plasma levels of lidocaine
0.5% and ropivacaine 0.2% when injected intravenously for
IVRA. METHODS: In a double-blind, cross-over study, ten volunteers
received IVRA with 40 mL ropivacaine 0.2% or lidocaine 0.5%
at least four days apart. Both cuffs of a double-cuff tourniquet
remained inflated until they could no longer be tolerated.
The incidence, duration and intensity of CNS side effects
were recorded at three, ten, and 30 min after tourniquet release
and correlated with simultaneous venous blood samples. RESULTS:
There was a lower incidence of CNS side effects with ropivacaine
(6/10 volunteers) when compared to lidocaine (10/10 volunteers).
There was also less duration of these side effects (mean ?
SD, 5.1 ? 5.2 min vs 11.7 ? 6.7 min). Measured total plasma
levels were highest at ten minutes with ropivacaine 0.2% (1.2
? 0.3 ?g?mL(-1)) and at three minutes with lidocaine 0.5%
(1.7 ? 0.6 ?g?mL(-1)). Peak CNS symptoms correlated with measured
venous plasma levels for lidocaine, but occurred earlier with
ropivacaine. CONCLUSIONS: We observed a lower incidence of
CNS side effects with ropivacaine as compared to lidocaine.
Although ropivacaine's greater lipid solubility should, theoretically,
lead to more CNS side effects, this was, likely, offset by
slower release from tissues and lesser percentage of unbound
(free) drug.
PMID: 11823395
Can J Anaesth 2002 Feb;49(2):165-168
The addition of tramadol to lidocaine does not reduce tourniquet
and postoperative pain during iv regional anesthesia: [L'ajout
de tramadol a la lidocaine ne reduit pas la douleur du garrot
pendant l'anesthesie iv regionale, ni la douleur postoperatoire].
Department of Anesthesia, Intensive Care and Pain Clinic,
(University of Rennes 1), University Hospital of Rennes, France,
and the Centre Medico-Chirurgical Saint?Vincent, Saint-Gregoire,
France.
[Record supplied by publisher]
PURPOSE: We conducted a prospective, randomized, double-blind
study to determine whether the combination of tramadol with
lidocaine 0.5% had an analgesic effect on tourniquet pain
during iv regional anesthesia and also on postoperative pain.
METHODS: Thirty patients scheduled for carpal tunnel decompression
were included in the study. Each patient received 3 mg?kg(-1)
of plain lidocaine 0.5% with 100 mg of tramadol (Group T)
or 2 mL of isotonic saline (Group C). The mixture was injected
into the isolated and exsanguinated arm. Pain was assessed
using a linear visual analog scale and a verbal rate scale
during the surgical procedure and the postoperative period
(240 min) and subsequently at interview at 24 hr. Analgesic
consumption was recorded. RESULT: There was no difference
in the pain scales and analgesic request at any of the time
periods studied. CONCLUSION: We conclude, therefore, that
for carpal tunnel operation under iv regional anesthesia,
the combination of tramadol and lidocaine is not more effective
than lidocaine alone.
PMID: 11823394
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Can J Anaesth 2002 Feb;49(2):151-64
Calcium channels - basic aspects of their structure, function
and gene encoding; anesthetic action on the channels - a review:
[Revue : notions de base sur la structure, la fonction et
l'encodage genetique des canaux calciques et action des anesthesiques
sur ces canaux].
Yamakage M, Namiki A
Department of Anesthesiology Sapporo Medical University School
of Medicine Sapporo Hokkaido Japan.
[Medline record in process]
PURPOSE: To review recent findings concerning Ca(2+) channel
subtype/structure/function from electrophysiological and molecular
biological studies and to explain Ca(2+) channel diseases
and the actions of anesthetics on Ca(2+) channels. SOURCE:
The information was obtained from articles published recently
and from our published work. Principal findings: Voltage-dependent
Ca(2+) channels serve as one of the important mechanisms for
Ca(2+) influx into the cells, enabling the regulation of intracellular
concentration of free Ca(2+). Recent advances both in electrophysiology
and in molecular biology have made it possible to observe
channel activity directly and to investigate channel functions
at molecular levels. The Ca(2+) channel can be divided into
subtypes according to electrophysiological characteristics,
and each subtype has its own gene. The L-type Ca(2+) channel
is the target of a large number of clinically important drugs,
especially dihydropyridines, and binding sites of Ca(2+) antagonists
have been clarified. The effects of various kinds of anesthetics
in a variety of cell types have been demonstrated, and some
clinical effects of anesthetics can be explained by the effects
on Ca(2+) channels. It has recently become apparent that some
hereditary diseases such as hypokalemic periodic paralysis
result from calcium channelopathies. CONCLUSION: Recent advances
both in electrophysiology and in molecular biology have made
it possible to clarify the Ca(2+) channel structures, functions,
genes, and the anesthetic actions on the channels in detail.
The effects of anesthetics on the Ca(2+) channels either of
patients with hereditary channelopathies or using gene mutation
techniques are left to be discovered.
PMID: 11823393, UI: 21681275
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Can J Anaesth 2002 Feb;49(2):132-6
Antidepressant treatment for chronic depressed patients
should not be discontinued prior to anesthesia: [Le traitement
antidepresseur ne devrait pas etre interrompu avant l'anesthesie
de patients atteints de depression chronique].
Kudoh A, Katagai H, Takazawa T
Departments of Anesthesiology, Hakodate Watanabe Hospital,
and Hirosaki National Hospital, Hirosaki, Aomori, Japan.
[Medline record in process]
PURPOSE: To investigate whether antidepressants administered
to patients for chronic depression patients should be continued
or discontinued before anesthesia. RESULTS: We studied 80
depressed patients who were scheduled to undergo orthopedic
surgery under general anesthesia. The patients were divided
randomly into two groups; patients in Group A (n=40) continued
antidepressants before surgery and patients in Group B (n=40)
discontinued antidepressants 72 hr before surgery. Two (5%)
out of 40 patients in Group A and eight (20%) out of 40 patients
in Group B had deterioration of depressive symptoms (P=0.04).
Delirium or confusion during the perioperative course occurred
in five patients (13%) in Group A and in 12 (30%) in Group
B (P=0.05). There were no significant differences in incidence
(5 vs 6%) of hypotension and arrhythmias during anesthesia
between the two groups. CONCLUSION: Antidepressants administered
to depressed patients should be continued before anesthesia.
Discontinuation of antidepressants did not increase the incidence
of hypotension and arrhythmias during anesthesia, but increased
symptoms of depression and delirium or confusion.
PMID: 11823389, UI: 21681271
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Can J Anaesth 2002 Feb;49(2):115-20
Should we use breathing filters in anesthesia?/Devrions-nous
utiliser des filtres respiratoires en anesthesie ?
Lessard MR, Trepanier CA
Departement d'anesthesie-reanimation, Centre hospitalier
affilie universitaire de Quebec, (hopital Enfant-Jesus), Universite
Laval, Quebec, Quebec, Canada.
A comparison of endotracheal intubation and use of the laryngeal
mask airway for ambulatory oral surgery patients.
Todd DW
PURPOSE: This study compared current experience with the
laryngeal mask airway (LMA) to previous experience with endotracheal
intubation for ambulatory patients receiving general anesthesia.
PATIENTS AND METHODS: A retrospective comparison of 157 patients
(50 endotracheal intubation [ET] and 107 LMA cases) was conducted.
The subjects were American Association of Anesthesiologist
(ASA) Class I and II patients who underwent outpatient general
anesthesia for dentoalveolar surgery. Procedure time, recovery
time, and cost of techniques were compared. RESULTS: The patients
undergoing a variety of outpatient dentoalveolar surgical
procedures under general anesthesia in the LMA group had a
shorter procedure time than the ET group (40 vs 44 minutes)
and had a significantly shorter recovery time (54 vs 67 minutes).
In addition, compared with the cost of delivering care with
ET, the LMA provided slightly lower cost per case ($20 to
$30 per case compared with $35 to $80 per case), depending
on the anesthetic technique used. Comparing the 2 techniques
for removal of 4 impacted third molars (25 patients ET and
68 patients LMA) revealed a similar procedure time of 39 minutes
for both groups, but a shorter recovery time for the LMA group
(54 vs 68 minutes). CONCLUSIONS: Use of the LMA has advantages
over endotracheal intubation for outpatients receiving general
anesthesia for dentoalveolar surgery. Copyright 2002 American
Association of Oral and Maxillofacial Surgeons J Oral Maxillofac
Surg 60:2-4, 2002
PMID: 11756995, UI: 21629633
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Obstet Gynecol 2002 Jan;99(1):75-9
Dose-range effects of propofol for reducing emetic symptoms
during cesarean delivery.
Fujii Y, Numazaki M
Department of Anesthesiology, University of Tsukuba Institute
of Clinical Medicine, Tsukuba City, Ibaraki, Japan. yfujii@igaka.md.tsukuba.ac.jp
OBJECTIVE: To evaluate the efficacy and safety of propofol
at subhypnotic doses for reducing emetic symptoms in parturients
undergoing cesarean delivery under spinal anesthesia. METHODS:
In a randomized, double-masked trial, 80 patients received
lidocaine intravenously 0.1 mg/kg (for injection pain relief)
followed by either placebo or propofol at three different
doses (0.5 mg/kg per hour, 1.0 mg/kg per hour, 2.0 mg/kg per
hour) (n = 20 in each group) immediately after clamping of
the umbilical cord. Emetic episodes and safety assessments
were performed during spinal anesthesia for cesarean delivery.
To estimate a sufficient sample size, it was calculated that
20 patients per group would be required with alpha =.05 and
beta =.2. RESULTS: The rate of patients experiencing no emetic
symptoms in an intraoperative, postdelivery period was 45%
with propofol 0.5 mg/kg per hour (P =.5), 80% with propofol
1.0 mg/kg per hour (P =.011), and 80% with propofol 2.0 mg/kg
per hour (P =.011), compared with placebo (40%). No clinically
serious adverse events caused by the study drugs were observed.
CONCLUSION: Propofol 1.0 mg/kg per hour is the minimum effective
subhypnotic dose for reducing emetic symptoms during cesarean
delivery. Increasing the dose to 2.0 mg/kg per hour provides
no further benefit.
PMID: 11777514, UI: 21636699
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Obstet Gynecol 2002 Jan;99(1):58-62
Dexamethasone for the prevention of nausea and vomiting
after dilatation and curettage: a randomized controlled trial.
Fujii Y, Uemura A
Department of Anesthesiology, University of Tsukuba Institute
of Clinical Medicine, Tsukuba City, Ibaraki, Japan. jfujii@igaku.tsukuba.ac.jp
OBJECTIVE: To evaluate the efficacy and safety of dexamethasone
administered intravenously at three different doses (4 mg,
8 mg, 16 mg) for the prevention of nausea and vomiting after
dilatation and curettage. METHODS: In a prospective, randomized,
double-masked, placebo-controlled trial, 120 women received
placebo or dexamethasone intravenously at doses of 4 mg, 8
mg, or 16 mg immediately before induction of anesthesia (n
= 30 in each group). Propofol-based general anesthetic was
used. Emetic episodes and safety assessments were performed.
To estimate a sufficient sample size, it was calculated that
30 patients per group would be required with alpha =.05 and
beta =.2. RESULTS: The rate of patients who were emesis-free
(no nausea, retching, or vomiting) 0-24 hours after anesthesia
was 57% with dexamethasone 4 mg (P =.796), 87% with dexamethasone
8 mg (P =.005), and 87% with dexamethasone 16 mg (P =.005),
compared with placebo (50%). Patients who had received dexamethasone
8 mg or 16 mg were more satisfied than those who had received
placebo (P <.05). No clinically important adverse events
were observed in any of the groups. CONCLUSION: Dexamethasone
8 mg is an effective antiemetic for preventing postoperative
nausea and vomiting 0-24 hours after anesthesia in women undergoing
propofol-based general anesthesia for termination of pregnancy.
Increasing the dose to 16 mg provided no additional benefit.
Publication Types:
Clinical trial
Randomized controlled trial
PMID: 11777511, UI: 21636696
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Obstet Gynecol 2002 Jan;99(1):29-34
Active pushing versus passive fetal descent in the second
stage of labor: a randomized controlled trial.
Hansen SL, Clark SL, Foster JC
Intermountain Health Care, Salt Lake City, Utah, USA.
OBJECTIVE: To compare perinatal outcomes among women with
epidural anesthesia who were encouraged to push at complete
dilatation with those who had a period of rest before pushing
began. METHODS: After a power analysis to determine appropriate
sample size (based upon an alpha error rate of.05% and 80%
power), a prospective randomized trial of 252 women with
epidural anesthesia was conducted. Patients were randomized
to a rest period or immediate pushing at complete dilatation.
Variables measured included rate of fetal descent, length
of time of pushing, the number and type of fetal heart rate
decelerations, Apgar scores, arterial cord pH values, perineal
injuries, type of delivery, length of second stage, maternal
fatigue, and endometritis. RESULTS: When a period of rest
was used before pushing, we found a longer second stage,
decreased pushing time, fewer decelerations, and, in primiparous
women, less fatigue compared with control patients. Apgar
scores, arterial cord pH values, rates of perineal injury,
instrument delivery, and endometritis were similar in both
groups. CONCLUSION: Delayed pushing was not associated with
demonstrable adverse outcome, despite second-stage length
of up to 4.9 hours. In select patients, such delay may be
of benefit.
TUTTO
IL MATERIALE CONTENUTO IN QUESTO SITO E' STATO REPERITO IN RETE. GLI AUTORI
NON SI ASSUMONO RESPONSABILITA' PER
DANNI A TERZI DERIVATI DA USO IMPROPRIO O ILLEGALE DELLE INFORMAZIONI
RIPORTATE O DA ERRORI RELATIVI AL LORO CONTENUTO.