Ultimo Aggiornamento: 31 Dicembre 2002

27 citations found

Acta Anaesthesiol Scand 2002 Apr;46(4):469-72

Post-operative paraplegia following spinal cord infarction.

Weinberg L, Harvey WR, Marshall RJ

Department of Anaesthesia, Royal Cornwall Hospital, Truro, Cornwall, England.

Thoracic epidural analgesia is a frequently utilised technique. Neurological complications are uncommon, but of grave consequence with significant morbidity. Spinal cord infarction following epidural anaesthesia is rare. We present a case where a hypertensive patient underwent an elective sigmoid colectomy under combined general/epidural anaesthesia for a suspected malignant abdominal mass. An epidural infusion was used for intra-operative and post-operative analgesia. During surgery, the blood pressure was labile and she was hypotensive. Postoperatively, the patient became confused, pyrexial and tachycardic and developed systemic inflammatory response syndrome requiring intensive care management. She developed a flaccid paralysis at L3 level with areflexia, analgesia and impaired sensation. A spinal cord infarct in the region of the conus extending into the thoracic cord was diagnosed. Complications of epidural anaesthesia are easily recognised when they develop immediately; their relationship to the anaesthesia and the post-operative period may be misjudged or underestimated when they appear after a delay, if neurological signs are masked by lack of patient cooperation and drowsiness or if the epidural anaesthesia is prolonged by long-acting drugs. New neurological deficits should be evaluated promptly to document the evolving neurological status and further testing or intervention should be arranged if appropriate. The association with epidural anaesthesia as a cause of paraplegia is reviewed. The aetiological factors that may have contributed to this tragic neurological complication are discussed.

PMID: 11952453, UI: 21949473

Acta Anaesthesiol Scand 2002 Apr;46(4):455-7

Rapid detection of oesophageal intubation: take care when using colorimetric capnometry.

Puntervoll SA, Soreide E, Jacewicz W, Bjelland E

Norwegian Air Ambulance, Stavanger, Norway. stein.atle.puntervoll@snola.no

BACKGROUND: Rapid detection of a misplaced endotracheal tube in the esophagus is crucial, especially in emergency situations. Hence, we have compared the ability of a colorimetric CO2 indicator (Colibri technology, CO2ntrol 1) and a capnography to differentiate oesophageal and tracheal intubation, with and without CO2 air in the esophagus. METHODS: Fourteen otherwise healthy patients were intubated with an endotracheal tube in the trachea under general anesthesia. After a positive verification of this endotracheal tube and established mechanical ventilation a second endotracheal tube was placed in the esophagus. Both were initially ventilated four times, and expired CO2 was measured with a mainstream capnograph and a colorimetric indicator. In the remaining five patients CO2 containing air was inserted into the esophagus first and then ventilated four times. RESULTS: Both the colorimetric indicator and mainstream capnograph verified correct placement of the endotracheal tube from the first ventilation. When the tube was placed in the esophagus, both methods correctly showed that no CO2 was present. However, in patients (n=5) with CO2 installed in their esophagus, the colorimetric indicator, but not the capnograph, had readings showing that CO2 was present. This may cause a misinterpretation of correct tracheal placement. CONCLUSIONS: We found that in emergency situations where CO2 containing air may be present in the esophagus, capnography should be the preferred method of verifying endotracheal and not oesophageal intubation. The tested colorimetric CO2 indicator (Colibri technology, CO2ntrol 1) is very sensitive to low CO2 values. It may therefore falsely indicate correct endotracheal intubation, even when the tube is in the oesophageus.

Publication Types:

• Clinical trial

PMID: 11952450, UI: 21949470

Acta Anaesthesiol Scand 2002 Apr;46(4):390-2

Ultrasound-guided central venous cannulation in infants and children.

Asheim P, Mostad U, Aadahl P

Department of Anesthesia and Intensive Care, Trondheim University Hospital, Trondheim, Norway. tilper@online.no

BACKGROUND: Percutaneous central venous cannulation in infants and children is a challenging procedure. Traditionally, an external landmark technique has been used to identify puncture site. An ultrasound-guided technique is now available and we wanted to evaluate this method in children and infants, looking specifically at the ease of use, success rate and complications. METHODS: Forty-two consecutive infants and children (median 16.5 [0-177] months and 10 [3-45] kg) scheduled for central venous catheter placement were registered. An ultrasound scanner made for guiding puncture of vessels was used. After locating the puncture site, a sterile procedure was performed using an accompanying kit to aid puncture of the vessel. RESULTS: Cannulation was successful in all patients and we had no complications during insertion of the catheters. The right internal jugular vein was preferred in most patients, and in 95% of the patients the vein was punctured at the first attempt. The median time from start of puncture to aspiration of blood was 12 (3-180) seconds. CONCLUSION: The ultrasound-guided technique for placement of central venous catheters was easy to apply in infants and children. It is our impression that it increased the precision and safety of the procedure in this group of patients.

Publication Types:

• Clinical trial

PMID: 11952438, UI: 21949458

Acta Anaesthesiol Scand 2002 Apr;46(4):372-7

Oral clonidine premedication reduces the EC50 of propofol concentration for laryngeal mask airway insertion in male patients.

Higuchi H, Adachi Y, Arimura S, Nitahara K, Satoh T

Department of Anesthesia, Self Defense Force Central Hospital, Tokyo, Japan. higu-chi@ka2.so-net.ne.jp

BACKGROUND: Oral clonidine, an alpha2-adrenergic receptor agonist, reduces the dose of propofol required for laryngeal mask airway (LMA) insertion. Target-controlled infusion (TCI) is becoming increasingly popular for propofol infusion. There is no information, however, on the propofol blood concentrations required for LMA insertion and the effect of oral clonidine premedication on these values. METHODS: Propofol at target effect-site concentrations from 4.0 to 12.0 microg/ml were randomly administered using TCI in three groups of healthy male patients (n=35 each) who were undergoing elective orthopedic surgery: control, 2.5 microg/kg clonidine, and 5.0 microg/kg clonidine groups. Nothing was administered to the control group. Clonidine(2.5 microg/kg or 5.0 microg/kg) was administered orally 90 min before arrival at the operating room in the clonidine groups. After equilibration between the blood- and effect-site for 15 min, insertion of the LMA was attempted. The EC50 for LMA insertion (measured propofol serum concentration in equilibrium with the effect-site at which 50% of patients do not respond to the insertion of the LMA) was determined by logistical regression. RESULTS: EC50+/-standard error values in the control, 2.5 microg/kg clonidine, and 5.0 microg/kg clonidine groups were 8.72+/-0.55, 7.76+/-0.60, and 5.84+/-0.58 microg/ml, respectively. The EC50 in the 5.0 microg/kg clonidine group was significantly lower than that in the control group (P < 0.01). CONCLUSIONS: The propofol concentration required for LMA insertion in healthy male patients is reduced by premedication with 5.0 microg/kg oral clonidine.

Publication Types:

• Clinical trial
• Randomized controlled trial

PMID: 11952435, UI: 21949455

Acta Anaesthesiol Scand 2002 Apr;46(4):355-60

Remifentanil infusion for cardiac catheterization in children with congenital heart disease.

Foubert L, Reyntjens K, De Wolf D, Suys B, Moerman A, Mortier E

Department of Anesthesia, Division of Cardiac Anesthesia, Ghent University Hospital, Belgium. Luc.Foubert@rug.ac.be

BACKGROUND: Cardiac catheterization of children with congenital heart disease is increasingly being performed under general anesthesia. Haemodynamic stability during anesthesia and fast and adequate recovery after the procedure is crucial in these patients. We performed a pilot study to evaluate hemodynamic stability when using remifentanil for anesthesia during cardiac catheterization. We also evaluated extubation times and recovery characteristics. METHODS: In a randomized, prospective, double-blind study 30 children (aged 1.5-20 months) received a continuous infusion of either 0.2 (group 0.2) or 0.3 microg/kg/min remifentanil (group 0.3) as part of a balanced anesthesia with 0.6 MAC sevoflurane. Heart rate, noninvasive arterial blood pressure, end tidal CO2 and pulse oxymetry were monitored throughout the procedure. Extubation times were noted, and recovery from anesthesia was evaluated using Aldrete scores. RESULTS: : Haemodynamic response to intubation was well blunted in both groups. No significant changes in hemodynamic variables were noted from induction of anesthesia until 10 min after intubation. From then on there was a decrease in HR and systolic arterial pressure, which remained significant throughout the procedure in both groups. Extubation times were similar in both groups: 7.3 min (2,1) in group 0.2 vs. 6.6 min (2,1) in group 0.3 (NS). The number of patients with an Aldrete score of nine or more was 14 (group 0.2) vs. 15 (group 0.3), 10 min after extubation (NS). CONCLUSION: Both dose regimens of remifentanil provided stable hemodynamic conditions during anesthesia for cardiac catheterization of children with congenital heart disease and allowed for rapid and adequate recovery.

Publication Types:

• Clinical trial
• Randomized controlled trial

PMID: 11952432, UI: 21949452

Acta Anaesthesiol Scand 2002 Apr;46(4):345-9

Intraoperative awareness: detected by the structured Brice interview?

Enlund M, Hassan HG

Department of Anesthesia and Intensive Care, Uppsala University Hospital, Sweden. mats.enlund@ltvastmanland.se

BACKGROUND: Awareness is a rare complication in general anesthesia, but its consequences are stressful. Efforts must be undertaken to prevent, diagnose, and, if occurring, treat it. The incidence of awareness is higher following anesthesia involving the use of muscle relaxants. As a part of a quality assurance program at our short-stay surgery all patients exposed to general anesthesia are routinely subjected to a Brice interview, which aims to evaluate our standard anesthetic technique regarding awareness. METHODS: The Brice interview was used prospectively in 5216 patients given a propofol/opioid anesthetic for day-case or short-stay surgery. Neuromuscular blocks were used only for surgical needs, not routinely. All patients were interviewed on discharge from the recovery room. A second interview, according to Brice, was undertaken by telephone 3-7 days later in the case of a notable intraoperative event, or otherwise after postoperative patient complaints. All patients were also interviewed by telephone 1-2 days postoperatively. RESULTS: None of the patient interviews indicated awareness. This was also the case in five non-relaxed patients who had an incident of light anesthesia with eye opening and gross motor response without forewarning. Neuromuscular blockade was used in 7% of patients. DISCUSSION: We were unable to detect intraoperative awareness. The anesthetic regimen, including minimal use of muscle relaxants, might be beneficial for awareness prevention. Alternatively, the diagnostic power, the timing of the Brice interview, or the number of interviews performed may be questioned.

Publication Types:

• Clinical trial

PMID: 11952430, UI: 21949450

Acta Anaesthesiol Scand 2002 Apr;46(4):343-4

Relax, be aware, and know what you are doing.

Sandin R

Publication Types:

• Comment
• Editorial

PMID: 11952429, UI: 21949449

Anesth Analg 2002 Jul;95(1):257-258

Business Cards and Anesthetic Practice.

Bhavani Shankar K

Department of Anesthesiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts. Department of Anesthesia & Intensive Care Medicine, The Leopold Franzens University of Innsbruck, Innsbruck, Austria. Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.

[Record supplied by publisher]

PMID: 12088991

Anesth Analg 2002 Jul;95(1):255

Myocardial ischemia during emergency anesthesia in a patient with systemic lupus erythematosus resulting from undiagnosed antiphospholipid syndrome.

Ozaki M, Minami K, Shigematsu A

Department of Anesthesiology, University of Occupational and Environmental Health, School of Medicine, Fukuoka, Japan.

[Medline record in process]

PMID: 12088987, UI: 22083413

Anesth Analg 2002 Jul;95(1):254

What to do with clonidine with long-acting local anesthetic in brachial plexus block?

Nadig M, Ekatodramis G, Borgeat A

Department of Anesthesia, Orthopedic University Clinic of Zurich/Balgrist, University Clinic of Zurich/Balgrist, Zurich, Switzerland. Division of Anesthesiology, Geneva University Hospitals, Geneva, Switzerland.

[Medline record in process]

PMID: 12088985, UI: 22083411

Anesth Analg 2002 Jul;95(1):251; discussion 251

Effectiveness of blinding when comparing nitrous oxide with topical anesthetic cream.

Flanagan N, Sherrington C

[Medline record in process]

Publication Types:

• Letter

PMID: 12088981, UI: 22083407

Anesth Analg 2002 Jul;95(1):243-8

Repeated deflation of a gas-barrier cuff to stabilize cuff pressure during nitrous oxide anesthesia.

Karasawa F, Matsuoka N, Kodama M, Okuda T, Mori T, Kawatani Y

Department of Anesthesiology, National Defense Medical College, Tokorozawa, Saitama, Japan.

[Medline record in process]

Although a nitrous oxide (N(2)O) gas-barrier cuff effectively limits the increase of cuff pressure during N(2)O anesthesia, there are few data assessing whether an N(2)O gas-barrier cuff is more beneficial for stabilizing intracuff pressure than standard endotracheal tubes when cuffs are repeatedly deflated to stabilize pressure during N(2)O anesthesia. In the present study, the pressure of air-filled standard-type cuffs (Trachelon; Terumo, Tokyo, Japan) and N(2)O gas-barrier type endotracheal tube cuffs (Profile Soft-Seal Cuff [PSSC]; Sims Portex, Kent, UK) was measured during 67% N(2)O anesthesia (n = 8 in each), during which the cuffs were repeatedly deflated every 30 min (Trachelon) or 60 min (PSSC) for the first 3 or 4 h. After aspirating the cuffs for 3 h, the cuff pressure exceeded 22 mm Hg in more than half of the patients in both groups. However, aspiration of the cuffs for 4 h decreased the maximal cuff pressure between deflation intervals in both groups (P < 0.01 for each), and increased the intracuff N(2)O concentration (P < 0.0001 for each). After deflating the cuffs over 4 h, the cuff pressure in both groups never exceeded 22 mm Hg during the subsequent 3 h, and intracuff N(2)O concentrations did not significantly change. Therefore, deflation of cuffs for 4 h during N(2)O anesthesia sufficiently stabilized cuff pressure and equilibrated the intracuff N(2)O concentrations in both groups. The use of the PSSC endotracheal tube might be more practical because of the smaller number of cuff deflations required, but the PSSC does not reduce the duration of cuff deflations to stabilize the pressure. IMPLICATIONS: We demonstrated that the N(2)O concentration and pressure in the N(2)O-barrier Profile Soft-Seal Cuff stabilized when the cuff was aspirated once an hour for 4 h during N(2)O anesthesia. The Profile Soft-Seal Cuff might be easier to use in clinical practice than standard endotracheal tubes because of the smaller number of cuff deflations required.

PMID: 12088978, UI: 22083404

Anesth Analg 2002 Jul;95(1):227-8

The Resolution of ST Segment Depressions After High Right Thoracic Paravertebral Block During General Anesthesia.

Ho AM, Lim HS, Yim AP, Karmakar MK, Lee TW

Departments of Anaesthesia and Intensive Care and Surgery, Chinese University of Hong Kong.

[Medline record in process]

IMPLICATIONS: Thoracic epidural, stellate ganglion, and thoracic paravertebral blocks all relieve angina. We report a case of intraoperative resolution of ST segment depression after a right thoracic paravertebral block.

PMID: 12088974, UI: 22083400

Anesth Analg 2002 Jul;95(1):198-203

Does spinal anesthesia cause hearing loss in the obstetric population?

Finegold H, Mandell G, Vallejo M, Ramanathan S

Magee-Women's Hospital, Department of Anesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.

[Medline record in process]

Lumbar puncture is believed to cause hypoacousis by causing cerebrospinal fluid leakage in older individuals. We hypothesized that parturients undergoing subarachnoid block (SAB) may experience hearing loss. We evaluated the effects of SAB on hearing in parturients undergoing elective cesarean delivery. We also compared two types of spinal needles: a pencil-point needle (24-gauge Sprotte needle) and a cutting needle (25-gauge Quincke needle). Sixty patients were studied: 20 received lumbar epidural block for labor analgesia (controls), 20 received a SAB with a Sprotte needle, and 20 others received a SAB with a Quincke needle for cesarean delivery. A tone audiometer was used to test for that decibel level at which the patient heard 125-, 250-, 500-, 1000-, 2000-, 4000-, and 8000-Hz frequencies. The hearing test was performed before anesthesia, after delivery, and on the first and second postoperative days. The results were analyzed by using repeated-measures analysis of variance at P < 0.05. No patient from any of the three groups developed a hearing loss either at low or high frequencies. Spinal anesthesia does not lead to significant hearing loss when a pencil- or a cutting-point needle is used in the obstetric population. IMPLICATIONS: Sixty obstetric patients were enrolled in the study to examine the possible effects of spinal anesthesia on their hearing. By using an audiometer, the patient's hearing was evaluated before delivery, after delivery, and for the following 2 days. There was no significant change of hearing in any of the patients.

PMID: 12088968, UI: 22083394

Anesth Analg 2002 Jul;95(1):177-83

Anesthesiologists and acute perioperative stress: a cohort study.

Kain ZN, Chan KM, Katz JD, Nigam A, Fleisher L, Dolev J, Rosenfeld LE

Departments of Anesthesiology, Pediatrics, Child Psychiatry, and Cardiology, Yale University School of Medicine, New Haven, Connecticut.

[Medline record in process]

Previous studies have indicated that many anesthesiologists exhibit symptoms of chronic stress. There is a paucity of data, however, regarding the existence of acute stress signs among anesthesiologists. Anesthesiologists from three practice settings (n = 38) were studied while they were anesthetizing 203 patients. Heart rate (HR) was recorded continuously and arterial blood pressure (BP) was measured hourly and immediately after each induction. Anxiety levels and salivary cortisol levels were also assessed after each induction. Comparison BP and HR data were obtained from the anesthesiologists during a nonclinical day. We found that anesthesiologists' HR increased during the anesthetic process compared with morning baseline HR (P = 0.008). This HR increase, however, was not clinically significant; the average HR during the anesthetic pro- cess ranged from 80 +/- 12 to 84 +/- 11 bpm. Similarly, although both systolic and diastolic BP after inductions were increased compared with baseline BP (P = 0.001), this increase was not clinically significant. In 9% of the inductions, however, systolic BP exceeded 140 mm Hg, and in 17% of all inductions, diastolic BP exceeded 90 mm Hg. Finally, the average BP of anesthesiologists during a clinical day was not different from the average BP during a nonclinical day (P = 0.9). Self-reported anxiety did not increase significantly after inductions (P = 0.15). An analysis of Holter tapes revealed no rhythm abnormalities and no signs of myocardial ischemia. We conclude that the practice of anesthesiology is associated with minor manifestations of acute physiologic stress during the perioperative process. IMPLICATIONS: Anesthesiologists experience minor psychologic stress while involved in the anesthetic process.

PMID: 12088964, UI: 22083390

Anesth Analg 2002 Jul;95(1):148-50

E-cylinder-powered mechanical ventilation may adversely impact anesthetic management and efficiency.

Taenzer AH, Kovatsis PG, Raessler KL

Department of Anesthesiology, Maine Medical Center, Portland, Maine.

[Medline record in process]

Anesthesiologists often administer care outside the operating room. These locations may depend on gas cylinders for their oxygen source more than the operating suites supplied by dedicated central pipelines. Using full E-cylinders, we determined the oxygen consumption of two often used, pneumatically driven anesthesia ventilators to answer three questions: How much time is available when mechanically ventilating patients in the setting of absent or malfunctioning central oxygen pipeline? How much oxygen is used by the ventilator to drive the bellows? How does changing the inspiratory to expiratory ratio and the inspiratory flow (Narkomed ventilator only) influence oxygen use? At a ventilation of 5 L/min, we found that mechanical ventilation consumes between 59% and 85% of the available oxygen in an E-cylinder to drive the ventilator at fresh gas flows ranging from 1 to 10 L/min. The time span until the low oxygen alarm sounded ranged from 38 to 99 min. Alteration of the inspiratory flow but not the inspiratory to expiratory ratio had a significant impact. Clinicians must recognize that mechanical ventilation using E-cylinders rapidly depletes this sole oxygen source and could jeopardize patient safety. Conversely, manual or spontaneous ventilation with low fresh gas flows minimizes oxygen depletion. IMPLICATIONS: The time available to ventilate patients with an E-cylinder tank as the sole oxygen source was found to be as short as 38 min. Clinicians must recognize that mechanical ventilation using oxygen cylinders rapidly depletes oxygen and could jeopardize patient safety.

PMID: 12088959, UI: 22083385

Anesth Analg 2002 Jul;95(1):103-8

Supplementing desflurane-remifentanil anesthesia with small-dose ketamine reduces perioperative opioid analgesic requirements.

Guignard B, Coste C, Costes H, Sessler DI, Lebrault C, Morris W, Simonnet G, Chauvin M

Department of Anesthesiology, Hopital Ambroise Pare, Assistance Publique Hopitaux de Paris, France.

[Medline record in process]

Relative large-dose intraoperative remifentanil could lead to the need for more postoperative analgesics. Intraoperative N-methyl-D-aspartate receptor antagonists, such as ketamine, decrease postoperative opioid use. We therefore tested the hypothesis that intraoperative small-dose ketamine improves postoperative analgesia after major abdominal surgery with remifentanil-based anesthesia. Fifty patients undergoing abdominal surgery under remifentanil-based anesthesia were randomly assigned to intraoperative ketamine or saline (control) supplementation. The initial ketamine dose of 0.15 mg/kg was followed by 2 microg. kg(-1). min(-1). In both groups, desflurane was kept constant at 0.5 minimum alveolar anesthetic concentration without N(2)O, and a remifentanil infusion was titrated to autonomic responses. All patients were given 0.15 mg/kg of morphine 30 min before the end of surgery. Pain scores and morphine consumption were recorded for 24 postoperative h. Less of the remifentanil was required in the Ketamine than in the Control group (P < 0.01). Pain scores were significantly larger in the Control group during the first 15 postoperative min but were subsequently similar in the two groups. The Ketamine patients required postoperative morphine later (P < 0.01) and received less morphine during the first 24 postoperative h: 46 mg (interquartile range, 34-58 mg) versus 69 mg (interquartile range, 41-87 mg, P < 0.01). No psychotomimetic symptoms were noted in either group. In conclusion, supplementing remifentanil-based anesthesia with small-dose ketamine decreases intraoperative remifentanil use and postoperative morphine consumption without increasing the incidence of side effects. Thus, intraoperative small-dose ketamine may be a useful adjuvant to intraoperative remifentanil. IMPLICATIONS: Supplementing remifentanil-based anesthesia with small-dose ketamine decreased intraoperative remifentanil use and postoperative morphine consumption. These data demonstrate that N-methyl-D-aspartate antagonists, such as ketamine, can be a useful adjuvant to intraoperative remifentanil.

PMID: 12088951, UI: 22083377

Anesth Analg 2002 Jul;95(1):98-102

Electro-acupuncture at the zusanli, yanglingquan, and kunlun points does not reduce anesthetic requirement.

Morioka N, Akca O, Doufas AG, Chernyak G, Sessler DI

Department of Anesthesiology, University of Louisville, Kentucky.

[Medline record in process]

We tested the hypothesis that electro-acupuncture at the Zusanli, Yanglingquan, and Kunlun acupuncture points on the legs decreases anesthetic requirement. Fourteen young, healthy volunteers were anesthetized with desflurane on two separate days. Needle electrodes were positioned at the three acupuncture points thought to produce a generalized sedative and analgesic effect. Needles were percutaneously placed on treatment days; on control days, they were insulated and taped near the insertion points. The electrodes were stimulated on the treatment day. Stimulation consisted of 2-Hz and 100-Hz currents alternated at 2-s intervals. When the end-tidal desflurane concentration of 5.5% was stable for 15 min, noxious electrical stimuli were administered via 25-gauge needles on both thighs (70 mA at 100 Hz for 10 s). Desflurane concentration was increased 0.5% when movement occurred and decreased 0.5% when it did not. An investigator, blinded to treatment, determined movement. These up-and-down sequences were continued until volunteers crossed from movement to no movement four times. A logistic regression determined the partial pressure of desflurane that produced a 50% likelihood of movement in response to noxious stimulation and consequently identified the minimum alveolar anesthetic concentration equivalent for desflurane. There was no significant difference in minimum alveolar anesthetic concentration equivalents between the electro-acupuncture (4.6% +/- 0.6%, mean +/- SD) and control (4.6% +/- 0.8%) days (P = 0.8). These data provided an 80% power for detecting a difference of 0.35 volume-percent between the groups. IMPLICATIONS: Electro-stimulation of three general acupuncture points on the leg did not reduce desflurane requirements. This type of acupuncture is thus unlikely to facilitate general anesthesia or decrease the need for anesthetic drugs.

PMID: 12088950, UI: 22083376

Anesth Analg 2002 Jul;95(1):88-97

The inhibitory effect of local anesthetics on bradykinin-induced phospholipase d activation in rat pheochromocytoma PC12 cells.

Chen J, Dohi S, Tan Z, Banno Y, Nozawa Y

Departments of Anesthesiology and Critical Care Medicine and Biochemistry, Gifu University School of Medicine.

[Medline record in process]

Bradykinin induces activation of phospholipase D (PLD) via B(2) receptors in neuronal cells. To demonstrate molecular mechanism(s) of local anesthetics, we examined whether and how local anesthetics affect bradykinin-induced PLD activation in PC12 cells. Using [(3)H]Palmitic acid-labeled PC12 cells stimulated with bradykinin, formation of [(3)H]phosphatidylbutanol was measured as a variable of PLD activity. Bradykinin-stimulated PLD activity seemed to peak at 2 min. Procaine, lidocaine, ropivacaine, bupivacaine, and tetracaine suppressed the bradykinin-induced PLD activation. We chose tetracaine, the most potent drug among the local anesthetics tested, to examine how local anesthetics affect phospholipase C, protein tyrosine kinase, and extracellular signal-regulated kinase, which are the molecules upstream of PLD. Tetra- caine at clinically relevant concentrations (1 approximately 10 x 10(-4) M) inhibited the bradykinin-induced PLD activation in a dose- and time-dependent manner, but neither tetrodotoxin nor nifedipine affected the PLD activation. Tetracaine (5 x 10(-4) M) slightly potentiated brady-kinin-induced phospholipase C activation. Bradykinin-stimulated protein tyrosine-phosphorylation and extracellular signal-regulated kinase activation were not affected by tetracaine. Tetracaine significantly decreased PLD activity of membrane fraction in PC12 cells. These results indicate that local anesthetics depress bradykinin-induced lipid signaling pathway(s) and may provide some clues to understanding the molecular mechanisms of these drugs for anesthesia or analgesia. IMPLICATIONS: Local anesthetics depressed the bradykinin-induced activation of phospholipase D (PLD) in PC12 cells. The effects of tetracaine, the most potent among the anesthetics tested, on the bradykinin-induced intracellular signaling molecules were examined. The bradykinin-induced PLD activation could be one of the potential intracellular signaling molecular sites of local anesthetic action.

PMID: 12088949, UI: 22083375

Anesth Analg 2002 Jul;95(1):78-82

Development of an appropriate list of surgical procedures of a specified maximum anesthetic complexity to be performed at a new ambulatory surgery facility.

Dexter F, Macario A, Penning DH, Chung P

Division of Management Consulting and Department of Anesthesia, University of Iowa, Iowa City.

[Medline record in process]

A common but difficult task for a hospital when it decides to open a freestanding ambulatory surgery facility is how to decide which surgical procedures should be done at the new facility. This is necessary in order to determine how many operating rooms to plan for the new facility and which ancillary services are needed on-site. In this case study, we describe a novel methodology that we used to develop a comprehensive list of procedures to be done at a new ambulatory facility. The level of anesthetic complexity of a procedure was defined by its number of ASA Relative Value Guide basic units. Broad categories of procedures (e.g., eye surgery) were defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification. We identified 22 categories that are of a type that every procedure in the category has no more than seven basic units. In addition, by analyzing all procedures that the hospital being studied actually performed on an ambulatory basis, we identified six other categories of procedures that were of a type that all procedures eligible for surgery at the new facility had seven or fewer basic units. IMPLICATIONS: We describe a novel method to develop a comprehensive list of procedures that have a prespecified maximum level of anesthetic complexity to be performed at a new ambulatory surgery facility.

PMID: 12088947, UI: 22083373

Anesth Analg 2002 Jul;95(1):72-7

Awareness and recall in outpatient anesthesia.

Wennervirta J, Ranta SO, Hynynen M

Department of Anesthesia and Intensive Care Medicine, Helsinki University Central Hospital, Children's Hospital, Helsinki, Finland.

[Medline record in process]

We studied the incidence of awareness and explicit recall during general anesthesia in outpatients versus inpatients undergoing surgery. During a 14.5-mo period, we structurally interviewed 1500 outpatients and 2343 inpatients. Among outpatients, there were five cases of awareness and recall (one with clear intraoperative recollections and four with doubtful intraoperative recollections). Of the inpatients, six reported awareness and recall (three with clear and three with doubtful intraoperative recollections). The incidence of clear intraoperative recollections was 0.07% in outpatients and 0.13% in inpatients. The difference in the incidence was not significant. Among outpatients, those with awareness and recall were given smaller doses of sevoflurane than those without awareness and recall (P < 0.05). In conclusion, awareness and recall are rare complications of general anesthesia, and outpatients are not at increased risk for this event compared with inpatients undergoing general anesthesia. IMPLICATIONS: Rapid recovery from general anesthesia is a crucial element of outpatient surgery. However, this practice may predispose a patient to receive less anesthetic, with increased risk for awareness and recall. We have shown that outpatients undergoing an operation using general anesthesia are not at increased risk for awareness compared with inpatients.

PMID: 12088946, UI: 22083372

Anesth Analg 2002 Jul;95(1):56-61

The effect on lung mechanics in anesthetized children with rapacuronium: a comparative study with mivacurium.

Fine GF, Motoyama EK, Brandom BW, Fertal KM, Mutich R, Davis PJ

Department of Anesthesiology and Division of Pulmonology, Children's Hospital of Pittsburgh.

[Medline record in process]

The administration of rapacuronium increases the risk of severe bronchospasm. There have been no studies of pulmonary function directly demonstrating airway constriction with rapacuronium in children. In this study, 10 ASA physical status I or II patients (aged 2-6 yr) were randomly divided into 2 equal groups, receiving either rapacuronium or mivacurium. Anesthesia was induced with sevoflurane and maintained with remifentanil (0.2-0.3 microg. kg(-1). min(-1)) and propofol (200-250 microg. kg(-1). min(-1)) infusions. We performed three sets of pulmonary function tests: baseline, after the administration of muscle relaxant, and after the administration of a beta(2) agonist. In both groups, there were no changes in static respiratory compliance. The increase in total respiratory system resistance after the administration of rapacuronium did not reach statistical significance (214.4% +/- 122.65% of baseline, P approximately 0.1), whereas maximal expiratory flow at 10% of forced vital capacity (MEF)(10) and MEF(functional residual capacity) on partial flow-volume curves by the forced deflation technique decreased markedly (53.4% +/- 18.49%, P < 0.01 and 41.3% +/- 27.42%, P < 0.001, respectively). With the administration of mivacurium, no changes were observed in respiratory system resistance (109.5% +/- 30.28%). MEF(10) decreased slightly (77.0% +/- 9.03%, P < 0.005) whereas MEF(FRC) did not (81.2% +/- 29.85%, not significant). After the administration of a beta(2) agonist, all measurements returned to baseline. Thus, the administration of rapacuronium consistently results in lower airway obstruction with minimal changes in static respiratory compliance when compared with mivacurium. IMPLICATIONS: Pulmonary function tests in the present study showed that rapacuronium consistently causes severe bronchoconstriction, confirming clinical case reports of bronchospasm. The bronchoconstriction is reversible with albuterol. Mivacurium also causes very mild subclinical bronchoconstriction.

PMID: 12088943, UI: 22083369

Anesth Analg 2002 Jul;95(1):42-9

The anesthetic considerations in patients with ventricular assist devices presenting for noncardiac surgery: a review of eight cases.

Stone ME, Soong W, Krol M, Reich DL

Department of Anesthesiology, The Mount Sinai School of Medicine, New York, New York.

[Medline record in process]

IMPLICATIONS: The number of patients supported by ventricular assist devices (VADs) that present for noncardiac surgery is increasing in our institution. Our recent experience with eight such patients is reported, along with a review of the most commonly implanted VADs and the anesthetic implications and considerations for VAD-supported patients undergoing noncardiac surgery.

PMID: 12088940, UI: 22083366

Br J Anaesth 2002 Apr;88(4):534-9

The proseal laryngeal mask: results of a descriptive trial with experience of 300 cases.

Evans NR, Gardner SV, James MF, King JA, Roux P, Bennett P, Nattrass R, Llewellyn R, Visu D

Department of Anaesthesia, University of Cape Town, Groote Schuur Hospital, Observatory, South Africa.

BACKGROUND: The ProSeal laryngeal mask airway (PLMA) is a new laryngeal mask device with a modified cuff and a drainage tube. METHODS: We assessed the PLMA in 300 anaesthetized adults either paralysed or breathing spontaneously. We assessed insertion characteristics, airway seal pressures, haemodynamic response to insertion, ease of gastric tube placement, gastric insufflation, and postoperative sore throat. RESULTS: Insertion was successful in 294 patients (98%) and graded as easy in 274 patients (91%). We found no difference in ease of insertion or success rate with either the introducer or the finger insertion method, or in paralysed or non-paralysed patients. Mean airway seal pressure was 29 cm H2O, and 59 patients (20%) had seal pressures greater than 40 cm H2O. No gastric insufflation was detected. Gastric tube placement was successful in 290 of 294 patients (98.6%). There was no cardiovascular response to insertion, with a small reduction in heart rate 5 min after insertion and significant decreases in mean arterial pressure at 1 and 5 min after insertion. Sore throat was noted in 23% patients after operation and in 16% of patients after 24 h, with 90% of the sore throats described as mild. CONCLUSIONS: The PLMA is a reliable airway management device that can give an effective glottic seal in paralysed and non-paralysed patients. The device allows the easy passage of a gastric tube, causes a minimal haemodynamic response to insertion, and an acceptable incidence of sore throat.

Publication Types:

• Evaluation studies

PMID: 12066730, UI: 22061547

Br J Anaesth 2002 Apr;88(4):520-6

Effect of perioperative administration of dexketoprofen on opioid requirements and inflammatory response following elective hip arthroplasty.

Iohom G, Walsh M, Higgins G, Shorten G

Department of Anaesthesia and Intensive Care Medicine, Cork University Hospital and National University of Ireland, Republic of Ireland.

BACKGROUND: In this double-blind, randomized, placebo-controlled trial, the safety and analgesic efficacy of perioperative dexketoprofen were evaluated. METHODS: Thirty ASA I or II patients undergoing elective hip arthroplasty were randomized to one of two groups. One group (D) received dexketoprofen 25 mg tds for 24 h before and 48 h after surgery; the second group (P) received placebo tablets at equivalent times. Hyperbaric 0.5% bupivacaine (17.5 mg if greater than 70 kg and 15 mg if less than 70 kg) and preservative-free morphine (0.6 mg) were administered intrathecally. Postoperatively, PCA was provided (bolus morphine sulphate 1 mg; lockout 5 min; no continuous infusion). RESULTS: The two groups were similar in terms of age, gender, weight, height, ASA class, duration of operation, and level of sensory block on arrival to the recovery room. Groups were also similar in terms of blood loss, transfusion requirements, ventilatory frequency, and haemodynamic variables. According to visual analogue pain scores patients in group D experienced less pain at 15 h (P=0.02) postoperatively. Cumulative morphine consumption was also less in group D compared with group P at 6 (0.06 (0.2) vs 0.85 (1.4) mg, P=0.04) and 48 h postoperatively (10.1 (8) vs 26.2 (20) mg, P<0.01). Plasma interleukin 6 concentrations increased postoperatively to a significantly lesser extent in group D than in group P (P=0.02). Nausea and vomiting were less (P<0.01) in group D compared with group P at 18 h postoperatively. Sedation scores were less (P=0.03) in group D. CONCLUSIONS: Perioperative administration of dexketoprofen 25 mg 8 hourly markedly improves analgesia and decreases opioid requirements (and associated adverse effects) following hip arthroplasty. It appears that this regimen decreases the postoperative pro-inflammatory response.

Publication Types:

• Clinical trial
• Randomized controlled trial

PMID: 12066728, UI: 22061545

Br J Pharmacol 2002 Jul;136(5):673-84

Pre- and postsynaptic volatile anaesthetic actions on glycinergic transmission to spinal cord motor neurons.

Cheng G, Kendig JJ

Department of Anesthesia, Stanford University School of Medicine, Stanford, California, CA 94305, U.S.A. Current address: Department of Pharmacology, Merck Research Laboratories, WP26-265, P.O. Box 4, 770 Sumneytown Pike, West Point, PA 19486, U.S.A.

[Medline record in process]

A common anaesthetic endpoint, prevention of withdrawal from a noxious stimulus, is determined primarily in spinal cord, where glycine is an important inhibitory transmitter. To define pre- and postsynaptic anaesthetic actions at glycinergic snyapses, the effects of volatile anaesthetic agents on spontaneous and evoked glycinergic currents in spinal cord motor neurons from 6 - 14-day old rats was investigated. The volatile anaesthetic agents enflurane, isoflurane and halothane significantly increased the frequency of glycinergic mIPSCs, enflurane to 190.4% of control+/-22.0 (mean+/-s.e.m., n=7, P<0.01), isoflurane to 199.0%+/-28.8 (n=7, P<0.05) and halothane to 198.2%+/-19.5 (n=7, P<0.01). However without TTX, isoflurane and halothane had no significant effect and enflurane decreased sIPSC frequency to 42.5% of control+/-12.4 (n=6, P<0.01). All the anaesthetics prolonged the decay time constant (tau) of both spontaneous and glycine-evoked currents without increasing amplitude. With TTX total charge transfer was increased; without TTX charge transfer was unchanged (isoflurane and halothane) or decreased (enflurane). Enflurane-induced mIPSC frequency increases were not significantly affected by Cd(2+) (50 microM), thapsigargin (1 - 5 microM), or KB-R7943 (5 microM). KB-R7943 and thapsigargin together abolished the enflurane-induced increase in mIPSC frequency. There are opposing facilitatory and inhibitory actions of volatile anaesthetics on glycine release dependent on calcium homeostatic mechanisms and sodium channels respectively. Under normal conditions (no TTX) the absolute amount of glycinergic inhibition does not increase. The contribution of glycinergic inhibition to anaesthesia may depend on its duration rather than its absolute magnitude.

PMID: 12086976, UI: 22081499

Neurosci Lett 2002 May 3;323(3):167-70

Does postural instability affect the initiation of human gait?

Fiolkowski P, Brunt D, Bishop M, Woo R

Department of Physical Therapy, University of Florida, P.O. Box 100154 HSC, Gainesville, FL 32610-0154, USA.

During gait initiation (GI), decoupling of the center of mass and center of pressure allows the center of mass to fall forwards. Subjects initiated gait rapidly before and after tibial nerve block of the tibial nerve. Static single limb stability, stance limb ground reaction forces, electromyogram and temporal data were measured. It was hypothesized that postural stability would decrease post-block and that this would affect the kinetic and temporal properties of GI. Subjects had significantly decreased postural stability post-block and changes in normal gait kinetics, however, no changes were noted in ground reaction forces or relative temporal data of the GI task. The finding that GI was unaffected by diminished single leg postural instability suggests that GI is a pre-programmed task.

PMID: 11959411, UI: 21957041