1: Anaesth Intensive Care 2002 Apr;30(2):223-5 Related Articles, Links

Prone position as a life-saving measure for acute pulmonary haemorrhage in a young adult with cystic fibrosis.

Savage R.

Department of Anaesthesia, John Hunter Hospital, Newcastle, NSW.

Fatal pulmonary haemorrhage is a rare complication of cystic fibrosis. A case of unexpected life-threatening pulmonary haemorrhage is presented, and the successful management of this problem including immediate prone ventilation. Different anaesthetic techniques, avoiding endotracheal intubation and positive pressure ventilation, which may avoid similar complications, are described.

PMID: 12002934 [PubMed - indexed for MEDLINE]

2: Anesth Analg 2002 Nov;95(5):1461; discussion 1461-2 Related Articles, Links

Comment on:  
Optimizing the benefits of outpatient preoperative anesthesia evaluation.

Pollard J.

Publication Types:
PMID: 12401649 [PubMed - indexed for MEDLINE]

3: Anesth Analg 2002 Nov;95(5):1423-7, table of contents Related Articles, Links
 
A new teaching model for resident training in regional anesthesia.

Martin G, Lineberger CK, MacLeod DB, El-Moalem HE, Breslin DS, Hardman D, D'Ercole F.

Department of Anesthesia, Duke University Health System, Duke North Hospital Room 3438, Box 3094, Durham, NC 27710, USA. marti091@mc.duke.edu

The adequacy of resident education in regional anesthesia is of national concern. A teaching model to improve resident training in regional anesthesia was instituted in the Anesthesiology Residency in 1996 at Duke University Health System. The key feature of the model was the use of a CA-3 resident in the preoperative area to perform regional anesthesia techniques. We assessed the success of the new model by comparing the data supplied by the Anesthesiology Residency to the Residency Review Committee for Anesthesiology for the training period July 1992-June 1995 (pre-model) and the training period July 1998-June 2001 (post-model). During the 3-yr training period, the pre-model CA-3 residents (n = 12) performed a cumulative total of 80 (58-105) peripheral nerve blocks (PNBs), 66 (59-74) spinal anesthetics, and 133 (127-142) epidural anesthetics. The CA-3 post-model residents (n = 10) performed 350 (237-408) PNBs, 107 (92-123) spinal anesthetics, and 233 (221-241) epidural anesthetics (P < 0.0001). All results are reported as median (interquartile range). We conclude that our new teaching model using our CA-3 residents as block residents in the preoperative area has increased their clinical exposure to PNBs. IMPLICATIONS: Inadequate exposure to peripheral nerve blocks has been a national problem. A teaching model instituted at Duke University Health System has resulted in a fourfold increase in exposure to peripheral nerve blocks compared with the national averages.

PMID: 12401637 [PubMed - indexed for MEDLINE]

4: Anesth Analg 2002 Nov;95(5):1419-22, table of contents Related Articles, Links
 
Intravenous regional anesthesia using prilocaine and neostigmine.

Turan A, Karamanlyoglu B, Memis D, Kaya G, Pamukcu Z.

Department of Anaesthesiology and Reanimation, Medical Faculty, Trakya University, 22030 Edirne, Turkey. alparslanturan@yahoo.com

Neostigmine has been added to local anesthetics for central and peripheral nerve blocks resulting in prolonged, increased anesthesia and improved analgesia. We conducted this study to evaluate the effects of neostigmine when added to prilocaine for IV regional anesthesia (IVRA). Thirty patients undergoing hand surgery were randomly assigned to two groups to receive IVRA. The control group received 1 mL of saline plus 3 mg/kg of prilocaine diluted with saline to a total dose of 40 mL; the study group received 0.5 mg of neostigmine plus 3 mg/kg of prilocaine diluted with saline to a total dose of 40 mL. Sensory and motor block onset and recovery, anesthesia quality determined by an anesthesiologist, anesthesia quality determined by a surgeon, and dryness of the operative field were noted. Heart rate, mean arterial blood pressure, and oxygen saturation values were noted at 1, 5, 10, 20, and 40 min before surgery and after tourniquet release. Time to first analgesic requirement was also noted. Shortened sensory and motor block onset times, prolonged sensory and motor block recovery times, improved quality of anesthesia, and prolonged time to first analgesic requirement were found in the neostigmine group. We conclude that neostigmine as an adjunct to prilocaine improves quality of anesthesia and is beneficial in IVRA. IMPLICATIONS: Neostigmine has been added to local anesthetics for central and peripheral nerve blocks. This study was conducted to evaluate the effects of neostigmine when added to prilocaine for IV regional anesthesia (IVRA). Neostigmine as an adjunct to prilocaine improves quality of anesthesia and is beneficial in IVRA.

Publication Types:
PMID: 12401636 [PubMed - indexed for MEDLINE]

5: Anesth Analg 2002 Nov;95(5):1381-3, table of contents Related Articles, Links
 
Preoperative risk factors of intraoperative hypothermia in major surgery under general anesthesia.

Kasai T, Hirose M, Yaegashi K, Matsukawa T, Takamata A, Tanaka Y.

Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kamigyoku, Kyoto 602-8566, Japan. kasai@koto.kpu-m.ac.jp

Preoperative factors, such as age and body habitus, affect intraoperative hypothermia during general anesthesia. In a preliminary study, we developed a logistic model to retrospectively evaluate predictors of intraoperative hypothermia in patients who received major surgery. The following factors were selected to develop the model: Z = -15.014 + 0.097 x (Age) + 0.263 x (Height) - 0.323 x (Weight) - 0.055 x (Preoperative systolic blood pressure) - 0.121 x (Preoperative heart rate). By using this model, the probability of hypothermia can be estimated by applying the following formula: Probability = 1/(1 + e(-)(Z)). If an estimated probability of hypothermia was >0.5, the sensibility of prediction was 81.5% and the specificity was 83%. In the second study, the model was applied prospectively to other patients, and the validity of the logistic model was evaluated. The core temperature showed a significant decrease in patients with a probability >0.7, who were predicted to be hypothermic, and their thermoregulatory vasoconstriction threshold also showed a significant decrease, compared with the patients with a probability <==0.3, who were predicted to be normothermic. We concluded that intraoperative hypothermia could be predicted from preoperative characteristics such as age, height, weight, systolic blood pressure, and heart rate. IMPLICATIONS: Increases in age and height and decreases in weight systolic blood pressure and heart rate are major preoperative risk factors of intraoperative hypothermia during major surgery.

Publication Types:
PMID: 12401629 [PubMed - indexed for MEDLINE]

6: Anesth Analg 2002 Nov;95(5):1339-43, table of contents Related Articles, Links
 
The effect of guanethidine and local anesthetics on the electrically stimulated mouse vas deferens.

Joyce PI, Rizzi D, Calo G, Rowbotham DJ, Lambert DG.

University Department of Anaesthesia and Pain Management, Leicester Royal Infirmary, Leicester LE1 5WW, UK.

Complex regional pain syndrome is often treated with the sympatholytic guanethidine and a local anesthetic in a Bier's block. The efficacy of this treatment has been questioned. Because local anesthetics inhibit the norepinephrine uptake transporter, we hypothesized that this variable efficacy results from the local inhibiting the uptake of guanethidine. In this study, we tested this hypothesis by using a sympathetically innervated mouse vas deferens preparation. Organ bath-mounted mouse vasa deferentia were electrically stimulated in the absence and presence of guanethidine, prilocaine, procaine, and cocaine in various combinations. Prilocaine (1 mM) induced an immediate inhibition of twitch response (maximum 100% after 2 min) that fully reversed after washing. Guanethidine (3 microM) also inhibited twitching by 95% +/- 3% in 15 min, but this effect was only partially reversed after 1 h of washing (33% +/- 12% of control). When prilocaine and guanethidine were added in combination, a reversal of 80% +/- 13% (at 1 h) was observed. Procaine (300 micro M) produced a transient increase (152% +/- 14%) in response. When co-incubated with guanethidine (3 microM), the twitch was reduced to 24% +/- 4% of control and was reversed to 77% +/- 7% after 1 h. Cocaine (30 microM) inhibited the twitch response to 53% +/- 8%, which was fully reversed by 1 h of washing. When co-incubated with guanethidine, the response was reduced to 39% +/- 6% of control and was reversed to 86% +/- 10% after 1 h. In all cases, the reversal produced by the combination was significantly more intense (P < 0.05) than that produced by guanethidine alone. Local anesthetics reduce the sympatholytic actions of guanethidine, and this may explain the variable efficacy of guanethidine in the treatment of complex regional pain syndrome. IMPLICATIONS: In this study, with a sympathetically innervated vas deferens preparation, local anesthetics reduced the efficacy of the sympatholytic guanethidine, questioning its co-administration in the pain clinic.

PMID: 12401623 [PubMed - indexed for MEDLINE]

7: Anesth Analg 2002 Nov;95(5):1324-30, table of contents Related Articles, Links
 
Narcotrend, bispectral index, and classical electroencephalogram variables during emergence from propofol/remifentanil anesthesia.

Schmidt GN, Bischoff P, Standl T, Voigt M, Papavero L, Schulte am Esch J.

Department of Anesthesiology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany. guschmid@uke.uni-hamburg.de

The aim of this study was to investigate modern and classical electroencephalographic (EEG) variables in response to remifentanil and propofol infusions. We hypothesized that modern EEG variables may indicate the effects of propofol but not of remifentanil. Twenty-five patients were included in the study after the end of elective spine surgery without any surgical stimulation. Baseline values were defined with remifentanil 0.3 microg. kg(-1). min(-1) and target-controlled infusion of propofol 3.0 microg/mL. EEG changes were evaluated 1, 3, 5, 7, and 9 min after the stop of remifentanil infusion, followed by a step-by-step reduction (0.2 microg/mL) every 3 min of target-controlled infusion propofol. Narcotrend (NT; classifying EEG stages from awake to deep anesthesia), bispectral index (BIS), EEG spectral frequency bands (%), 50% (Median) and 95% percentiles (spectral edge frequency), mean arterial blood pressure, heart rate, and oxygen saturation were detected at every time point. The end of remifentanil application resulted in significant increases in %alpha, spectral edge frequency, mean arterial blood pressure, and %theta and decreases in %delta (P < 0.05). NT, BIS, Median, heart rate, and oxygen saturation were unchanged. Decreases in propofol concentration were associated with statistically significant increases in NT and BIS (P < 0.05). Thus, the sedative-hypnotic component of propofol could be estimated by modern EEG variables (NT and BIS), whereas the analgesic component provided by remifentanil was not indicated. However, during conditions without surgical stimulation, neither NT nor BIS provided an adequate assessment of the depth of anesthesia when a remifentanil infusion was used. IMPLICATIONS: We investigated modern and classical electroencephalographic (EEG) variables during emergence from propofol/remifentanil anesthesia. Modern EEG variables indicate changes of infusion in propofol, but not in remifentanil. Thus, modern EEG variables did not provide an adequate assessment of depth of anesthesia when remifentanil was used.

Publication Types:
PMID: 12401620 [PubMed - indexed for MEDLINE]

8: Anesth Analg 2002 Nov;95(5):1318-23, table of contents Related Articles, Links
 
The auditory steady-state response is not a suitable monitor of anesthesia.

Pockett S, Tan SM.

Department of Physics, University of Auckland, Private Bag 92019, Auckland, New Zealand. s.pockett@auckland.ac.nz

Previous studies show that the human 40-Hz auditory steady-state response (ASSR) disappears on induction of general anesthesia, suggesting that it may be a good candidate for a monitor of anesthesia. In this study, we aimed to learn whether all normal alert adults display ASSRs with adequate signal-to-noise ratio. Clicks were presented at a series of frequencies between 35 and 70 Hz and electroencephalographic records taken at the vertex were Fourier transformed. ASSRs were observable as sharp peaks in the electroencephalograph spectrum at the frequency of the clicks. Initial results showed that a discernible ASSR could not be obtained from about half the subjects studied at any click frequency used. Further investigation revealed that in subjects whose ASSR was undetectable in the alert state, induction of a drowsy mental state resulted in appearance of an observable ASSR. This was attributable to an increase in signal in the drowsy state, not to a decrease in noise. We conclude that, because a significant proportion of subjects do not display easily recordable ASSRs when alert, it is not practical to use disappearance of the ASSR as a routine test for adequacy of anesthesia. IMPLICATIONS: Auditory steady-state responses (ASSRs) are brain waves evoked by auditory stimuli. Because they reportedly disappear under general anesthesia, they have been suggested as potential indicators of anesthetic depth. However, in this study, we show that about half our normal adult subjects did not produce measurable ASSRs when awake. This suggests that ASSRs are not good candidates for use in monitoring anesthetic depth during surgery.

PMID: 12401619 [PubMed - indexed for MEDLINE]

9: Anesth Analg 2002 Nov;95(5):1274-81, table of contents Related Articles, Links
 
The effects of general anesthetics on norepinephrine release from isolated rat cortical nerve terminals.

Pashkov VN, Hemmings HC Jr.

Departments of Anesthesiology and Pharmacology, Weill Medical College of Cornell University, 525 East 68th Street, New York, NY 10021, USA.

Intravenous and volatile general anesthetics inhibit norepinephrine (NE) release from sympathetic neurons and other neurosecretory cells. However, the actions of general anesthetics on NE release from central nervous system (CNS) neurons are unclear. We investigated the effects of representative IV and volatile anesthetics on [(3)H]NE release from isolated rat cortical nerve terminals (synaptosomes). Purified synaptosomes prepared from rat cerebral cortex were preloaded with [(3)H]NE and superfused with buffer containing pargyline (a monoamine oxidase inhibitor) and ascorbic acid (an antioxidant). Basal (spontaneous) and stimulus-evoked [(3)H]NE release was evaluated in the superfusate in the absence or presence of various anesthetics. Depolarization with increased concentrations of KCl (15-20 mM) or 4-aminopyridine (0.5-1.0 mM) evoked concentration- and Ca(2+)-dependent increases in [(3)H]NE release from rat cortical synaptosomes. The IV anesthetics etomidate (5-40 microM), ketamine (5-30 microM), or pentobarbital (25-100 microM) did not affect basal or stimulus-evoked [(3)H]NE release. Propofol (5-40 microM) increased basal [(3)H]NE release and, at larger concentrations, reduced stimulus-evoked release. The volatile anesthetic halothane (0.15-0.70 mM) increased basal [(3)H]NE release, but did not affect stimulus-evoked release. These findings demonstrate drug-specific stimulation of basal NE release. Noradrenergic transmission may represent a presynaptic target for selected general anesthetics in the CNS. Given the contrasting effects of general anesthetics on the release of other CNS transmitters, the presynaptic actions of general anesthetics are both drug- and transmitter-specific. IMPLICATIONS: General anesthetics affect synaptic transmission both by altering neurotransmitter release and by modulating postsynaptic responses to transmitter. Anesthetics exert both drug-specific and transmitter-specific effects on transmitter release: therapeutic concentrations of some anesthetics stimulate basal, but not evoked, norepinephrine release, in contrast to evoked glutamate release, which is inhibited.

PMID: 12401610 [PubMed - indexed for MEDLINE]

10: Anesth Analg 2002 Nov;95(5):1219-23, table of contents Related Articles, Links
 
Caudal anesthesia in children: effect of volume versus concentration of bupivacaine on blocking spermatic cord traction response during orchidopexy.

Verghese ST, Hannallah RS, Rice LJ, Belman AB, Patel KM.

Department of Anesthesiology, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA. sverghes@cnmc.org

In this study we compared the intensity and level of caudal blockade when two different volumes and concentrations of a fixed dose of bupivacaine were used. Fifty children, 1-6 yr old, undergoing unilateral orchidopexy received a caudal block with a fixed 2 mg/kg dose of bupivacaine immediately after the induction. Group 1 (n = 23) received 0.8 mL/kg of 0.25% bupivacaine, whereas Group 2 (n = 27) received 1.0 mL/kg of 0.2% bupivacaine. Epinephrine 1:400,000 and 0.1 mL of sodium bicarbonate per 10 mL of local anesthetic solution were added. There were no statistically significant differences between the two groups in their anesthesia, surgery, recovery, and discharge times. Fifteen patients (65.2%) in Group 1 required an increase in inspired halothane concentration to block hemodynamic and/or ventilatory response during spermatic cord traction, as compared with 8 patients (29.6%) in Group 2 (P = 0.022). In the recovery room, four (17.4%) patients in Group 1 required rescue treatment with fentanyl, versus two (7.4%) in Group 2 (P = 0.372). In children undergoing orchidopexy, a caudal block with a larger volume of dilute bupivacaine is more effective than a smaller volume of the standard 0.25% solution in blocking the peritoneal response during spermatic cord traction, with no change in the quality of postoperative analgesia. IMPLICATIONS: In children undergoing orchidopexy, a caudal block with a larger volume of dilute bupivacaine is more effective than a smaller volume of the more concentrated solution in blocking the peritoneal response during spermatic cord traction, with no change in the quality of postoperative analgesia.

Publication Types:
PMID: 12401597 [PubMed - indexed for MEDLINE]

11: Anesth Analg 2002 Nov;95(5):1207-14, table of contents Related Articles, Links
 
Intrathecal versus IV fentanyl in pediatric cardiac anesthesia.

Pirat A, Akpek E, Arslan G.

Department of Anesthesiology, Baskent University Faculty of Medicine, No. 45 Bahcelievler, 06490 Ankara, Turkey. arashpirat@hotmail.com

Systemic large-dose opioids are widely used in pediatric cardiac anesthesia, but there are no randomized, prospective studies regarding the use of intrathecal (IT) opioids for these procedures. In this randomized, prospective study, we compared cardiovascular and neurohumoral responses during IT or IV fentanyl anesthesia for pediatric cardiac surgery. Thirty children aged 6 mo to 6 yr were anesthetized with an IV fentanyl bolus of 10 micro g/kg. This was followed by a fentanyl infusion of 10 micro g. kg(-1). h(-1) (Group IV; n = 10), 2 micro g/kg of IT fentanyl (Group IT; n = 10), or combined IV and IT protocols (Group IV + IT; n = 10). Heart rate, mean arterial blood pressure, additional fentanyl doses, time to first analgesic requirement, COMFORT and Children's Hospital of Eastern Ontario Pain Scale scores, and extubation time were recorded. Blood cortisol, insulin, glucose, and lactate levels were measured presurgery, poststernotomy, during the rewarming phase of cardiopulmonary bypass (CPB), and 6 and 24 h after surgery. The patients' urinary cortisol excretion rates were also measured during the first postoperative day. The findings in all three groups were statistically similar, except for higher blood glucose levels during CPB in Group IT compared with Group IV (P < 0.004). Group IV + IT was the only group in which the increases in heart rate and mean arterial blood pressure from presurgery to poststernotomy were not significant. The 24-h urinary cortisol excretion rates ( micro g. kg(-1). d(-1)) were 61.51 +/- 39, 92.54 +/- 67.55, and 40.15 +/- 29.69 for Groups IV, IT, and IV + IT, respectively (P > 0.05). A single IT injection of fentanyl 2 micro g/kg offers no advantage over systemic fentanyl (10 micro g/kg bolus and 10 micro g. kg(-1). h(-1)) with regard to hemodynamic stability or suppression of stress response. The combination of these two regimens may provide better hemodynamic stability during the pre-CPB period and may be associated with a decreased 24-h urinary cortisol excretion rate. IMPLICATIONS: In this prospective, randomized study, we investigated the adequacy of a single intrathecal injection of fentanyl for intraoperative analgesia, compared the effects of IT and IV fentanyl on stress response, and assessed for an additive effect of IT and IV fentanyl administration in pediatric cardiac anesthesia. The results with these three different anesthetic regimens were similar regarding anesthesia depth and level of stress response. However, the combination of IT and IV routes may provide better hemodynamic stability and a less pronounced stress response, as reflected by 24-h urinary cortisol excretion.

Publication Types:
PMID: 12401595 [PubMed - indexed for MEDLINE]

12: Anesth Analg 2002 Nov;95(5):1196-7, table of contents Related Articles, Links
 
Supine hypertension during general anesthesia in a patient taking midodrine.

Chaimberg KH, Travis KW.

Department of Anesthesia, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA. kathleen.h.chaimberg@hitchcock.org

IMPLICATIONS: Midodrine, a drug used to treat symptomatic orthostatic hypotension, may cause or exacerbate supine hypertension. We describe a case of a patient taking midodrine who exhibited severe hypertension during general anesthesia. Possible preventive measures to avoid this complication are discussed.

PMID: 12401592 [PubMed - indexed for MEDLINE]

13: Anesth Analg 2002 Nov;95(5):1179-81, table of contents Related Articles, Links
 
Epidural anesthesia and analgesia in liver resection.

Matot I, Scheinin O, Eid A, Jurim O.

Department of Anesthesiology, Hadassah University Medical Center, The Hebrew University of Jerusalem, Jerusalem 91120, Israel.

IMPLICATIONS: In patients undergoing major liver resection, the decision to introduce an epidural catheter and the timing of its removal should be made with care because of the prolonged changes in platelet count and in prothrombin time that develop in some patients.

Publication Types:
PMID: 12401587 [PubMed - indexed for MEDLINE]

14: Anesth Analg 2002 Oct;95(4):1127-8 Related Articles, Links

Comment on:  
To cite or not to cite.

Nagase K, Ando-Nagase K.

Publication Types:
PMID: 12351322 [PubMed - indexed for MEDLINE]

15: Anesth Analg 2002 Oct;95(4):1121-2 Related Articles, Links

Comment on:  
Increased postoperative arterial blood pressure stability with continuous epidural infusion of clonidine in children.

G Bergendahl HT, Lonnqvist PA, De Negri P, Ivani G, Eksborg S.

Publication Types:
PMID: 12351311 [PubMed - indexed for MEDLINE]

16: Anesth Analg 2002 Oct;95(4):1119; discussion 1119-20 Related Articles, Links

Comment on:  
Sympathectomy for acute pulmonary embolism.

Stratmann G.

Publication Types:
PMID: 12351308 [PubMed - indexed for MEDLINE]

17: Anesth Analg 2002 Oct;95(4):1103-7, table of contents Related Articles, Links
 
Capsicum plaster at the korean hand acupuncture point reduces postoperative nausea and vomiting after abdominal hysterectomy.

Kim KS, Koo MS, Jeon JW, Park HS, Seung IS.

Department of Anesthesiology, Hanyang University Hospital, Seoul, Korea. kimks@hanyang.ac.kr

Postoperative nausea and vomiting (PONV) are still common and distressing problems after general anesthesia, especially in patients undergoing abdominal hysterectomy. We studied a nonpharmacological therapy of PONV-capsicum plaster (PAS)-at either the Korean hand acupuncture point K-D2 or the Chinese acupuncture point Pericardium 6 (P6) of both hands. One-hundred-sixty healthy patients were included in a randomized, double-blinded study: 60 patients were in the control group, 50 patients were in the K-D2 group, and 50 patients were in the P6 group. PAS was applied at the K-D2 point in the K-D2 group and at the P6 point in the P6 group, whereas in the control group, an inactive tape was fixed at the K-D2 point of both hands. The PAS was applied before the induction of anesthesia and removed at 8 h after surgery. The incidence of PONV and the need for rescue medication were evaluated at predetermined time intervals. In the treatment group, the incidence of vomiting was significantly less (22% for the K-D2 group and 26% for the P6 group) than in the control group (56.7%) at 24 h after surgery (P < 0.001). The need for rescue antiemetics was significantly less in the treatment groups compared with the control group (P < 0.001). We conclude that PAS at the Korean hand acupuncture point K-D2 was an effective method for reducing PONV, as was PAS at the P6 acupoint, after abdominal hysterectomy. IMPLICATIONS: Capsicum plaster at either the Korean hand acupuncture point K-D2 or the Pericardium 6 acupoint reduces postoperative nausea and vomiting in patients undergoing abdominal hysterectomy.

Publication Types:
PMID: 12351304 [PubMed - indexed for MEDLINE]

18: Anesth Analg 2002 Oct;95(4):1090-3, table of contents Related Articles, Links
 
Endotracheal intubation with a gum-elastic bougie in unanticipated difficult direct laryngoscopy: comparison of a blind technique versus indirect laryngoscopy with a laryngeal mirror.

Weisenberg M, Warters RD, Medalion B, Szmuk P, Roth Y, Ezri T.

Departments of Anesthesia, Cardiothoracic Surgery, and Otorhynolaryngology, Wolfson Medical Center, Holon, affiliated with Sackler School of Medicine, Tel Aviv, Israel.

We evaluated the efficacy of intubation over a gum-elastic bougie by using either a blind technique or indirect laryngoscopy with a laryngeal mirror in patients with unexpected difficult direct laryngoscopy. In a prospective study, 60 consecutive patients with an unexpected Grade III or IV direct laryngoscopy were randomly allocated for intubation with a gum-elastic bougie either blindly (Group 1) or by indirect laryngoscopy with a laryngeal mirror (Group 2). We evaluated the failure rate of each method of intubation, complications related to either method, and the time required for intubation. Out of 725 patients evaluated over a 2-mo period, 60 patients (8.3%) had a Grade III laryngoscopy, and 30 of these were randomized into each group. There were 8 failed intubations in Group 1 compared with 1 failed intubation in Group 2 (P < 0.05). All eight failures in the blind intubation group ended with esophageal intubation. No additional complications were noted in either group. The time required for endotracheal intubation with each group was not significantly different (45 +/- 10 s versus 44 +/- 11 s). We conclude that intubation with a gum-elastic bougie had a lower failure rate using indirect laryngoscopy with a laryngeal mirror than a traditional blind technique. IMPLICATIONS: We evaluated the efficacy of intubation over a gum-elastic bougie by using either a blind technique or a laryngeal mirror. Intubation with a gum-elastic bougie had a lower failure rate using indirect laryngoscopy with a laryngeal mirror (P < 0.05) than a traditional blind technique.

Publication Types:
PMID: 12351301 [PubMed - indexed for MEDLINE]

19: Anesth Analg 2002 Oct;95(4):1087-9, table of contents Related Articles, Links
 
The breaking of an intrathecally-placed epidural catheter during extraction.

Ugboma S, Au-Truong X, Kranzler LI, Rifai SH, Joseph NJ, Salem MR.

Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, Illinois 60657, USA.

IMPLICATIONS: Misplacement of an epidural catheter into the subarachnoid space is a recognized complication. However, breakage of an intrathecal epidural catheter during removal presents a dilemma. Appropriate imaging, a neurosurgical consultation, and aggressive surgical exploration and extraction of the retained piece are warranted, even in the asymptomatic patient.

PMID: 12351300 [PubMed - indexed for MEDLINE]

20: Anesth Analg 2002 Oct;95(4):1075-9, table of contents Related Articles, Links
 
Four-injection brachial plexus block using peripheral nerve stimulator: a comparison between axillary and humeral approaches.

Sia S, Lepri A, Campolo MC, Fiaschi R.

Department of Anesthesiology, Centro Traumatologico Ortopedico, Azienda Ospedaliera Careggi, Firenze, Italy. sia3@interfree.it

We conducted this prospective, randomized study to compare the success rate, performance time, and onset time of surgical anesthesia of a four-injection brachial plexus block performed at the axillary (Group Axillary; n = 50) or at the humeral (Group Humeral; n = 50) level using a peripheral nerve stimulator. All patients received 40 mL of a mixture of equal parts of 0.5% bupivacaine and 2% lidocaine. Four patients in Group Axillary and two in Group Humeral were excluded from the study because all of the four nerves were not localized in the allotted time. The incidence of complete block (91% versus 89%), defined as block of all the sensory areas below the elbow, and the onset time of sensory block (15 +/- 6 min versus 16 +/- 7 min) were not different between the groups. The performance time was shorter in Group Humeral (7 +/- 2 min versus 8 +/- 2 min; P < 0.005). Block performance pain was lower in Group Axillary patients (16 +/- 9 min versus 23 +/- 12 min; P < 0.005). For four-injection brachial plexus block, we conclude that both the axillary and the humeral approaches provide a high success rate and a rapid onset of sensory anesthesia; the differences found between the groups could be considered clinically unimportant. IMPLICATIONS: Two methods of brachial plexus block using a nerve-stimulator were compared in a prospective study. A four-injection technique was performed at the axillary or at the humeral level. Both approaches provided a fast onset and a high success rate. The differences found between the groups could be considered clinically unimportant.

Publication Types:
PMID: 12351298 [PubMed - indexed for MEDLINE]

21: Anesth Analg 2002 Oct;95(4):1071-4, table of contents Related Articles, Links
 
The anatomic relationship of the sciatic nerve to the lesser trochanter: implications for anterior sciatic nerve block.

Ericksen ML, Swenson JD, Pace NL.

Department of Anesthesiology, University of Utah, Salt Lake City 84132, USA.

Classic descriptions of the anterior sciatic nerve block suggest needle placement at the level of the lesser trochanter of the femur. Recently, investigators have reported that the sciatic nerve is not accessible at this level. To define more accurately the anatomic relationship of the sciatic nerve to the lesser trochanter, we analyzed magnetic resonance scans performed on 20 patients in the supine position. After IRB approval, magnetic resonance scans of the hip and proximal femur were reviewed in 20 supine patients in the neutral position. Images from five axial levels were studied, specifically, at the level of the lesser trochanter and at 1-cm intervals inferior to the lesser trochanter for 4 cm. In each axial image, the medial or lateral distance was measured from the sciatic nerve to a sagittal plane at the medial border of the femur. If the sciatic nerve was lateral to this sagittal plane (inaccessible), the distance was assigned a negative value, and if the sciatic nerve was medial to the sagittal plane (accessible), the distance was assigned a positive value. The distance between the coronal plane at the anterior border of the femur and the coronal plane through the sciatic nerve was also recorded for each level. At the level of the lesser trochanter, the sciatic nerve was lateral to the femoral border (inaccessible) in 13 of 20 patients with a mean distance of -4.0 +/- 7.7 mm. At 4 cm below the lesser trochanter, the sciatic nerve was medial to the femoral border (accessible) in 19 of 20 patients with a mean distance 7.8 +/- 5.8 mm. The distance from the anterior border of the femur to the sciatic nerve was 42.9 +/- 5.8 mm at the level of the lesser trochanter and 45.7 +/- 9.5 mm at 4 cm below the lesser trochanter. The classic description of the anterior approach to the sciatic nerve suggests that the needle be walked off medially at the level of the lesser trochanter. Our data are consistent with recent reports suggesting that in the majority of subjects, the position of the sciatic nerve relative to lesser trochanter made it inaccessible from an anterior approach at this level. In contrast, at 4 cm below the lesser trochanter, the sciatic nerve was medial to the femur in 19 of 20 subjects. We conclude that needle insertion medial to the proximal femur, 4 cm below the lesser trochanter, is a more direct anatomical approach to the anterior sciatic nerve block. IMPLICATIONS: Magnetic resonance images suggest that in the majority of supine subjects, the sciatic nerve is lateral to the lesser trochanter of the femur and therefore not accessible using the classic anterior approach. By contrast, 4 cm below the lesser trochanter, the sciatic nerve is consistently medial to the femoral shaft and therefore may be more accessible using an anterior approach.

Publication Types:
PMID: 12351297 [PubMed - indexed for MEDLINE]

22: Anesth Analg 2002 Oct;95(4):1067-70, table of contents Related Articles, Links
 
The median approach to transsacral epidural block.

Nishiyama T, Hanaoka K, Ochiai Y.

Surgical Center, The Institute of Medical Science, Department of Anesthesiology, The University of Tokyo, USA. nishiyam@ims.u-tokyo.ac.jp

Transsacral epidural block may be useful for surgery or cancer pain affecting the rectal, anal, or urethral region. The procedure through the dorsal sacral foramen is difficult because of the long insertion route. We investigated whether the transsacral epidural block could be simplified by using a median approach instead of a lateral approach through the foramen. Thirty patients for transurethral resection of bladder tumor had a catheter placed 5 cm cephalad at S2-3 (15 patients) or caudal (15 patients) epidural space using a 19-gauge Tuohy needle by the median approach. Lidocaine 2% 15 mL was administered for anesthesia. Anesthesia level (sensory block to cold), hemodynamics, and side effects were compared between the two approaches. The success rate of anesthesia was 87% for transurethral resection of bladder tumor (proximal anesthesia level higher than T10) and 100% for the sacral region (S1-5) in both groups. The highest level of anesthesia (median, T8 in the S2-3 group and T9 in the caudal group) was obtained in 20 min in both groups. No side effects were observed. We conclude that the median transsacral epidural approach is technically feasible in adults and presents an alternative to caudal block. IMPLICATIONS: The median approach to transsacral epidural block has been described in children. We found that it is technically feasible in adults and presents an alternative to caudal block for procedures on the rectal, anal, or urethral region.

Publication Types:
PMID: 12351296 [PubMed - indexed for MEDLINE]

23: Anesth Analg 2002 Oct;95(4):1049-51, table of contents Related Articles, Links
 
The impact of hypercapnia on systolic cerebrospinal fluid peak velocity in the aqueduct of sylvius.

Kolbitsch C, Lorenz IH, Hormann C, Schocke MF, Kremser C, Moser PL, Pfeiffer KP, Benzer A.

Department of Anaesthesia and Intensive Care Medicine, University of Innsbruck, Austria. christian.kolbitsch@uibk.ac.uk

Phase-contrast magnetic resonance imaging measurements of systolic cerebrospinal fluid peak velocity (CSFVPeak) in the aqueduct of Sylvius have been shown to be sensitive enough to detect even minor changes in cerebral compliance. Clinically relevant changes in cerebral compliance can be caused by changes in cerebral blood volume (CBV). Changes in arterial carbon dioxide partial pressure, which correlate well with end-tidal carbon dioxide concentration (ETCO(2)), cause changes in CBV. In this study, we investigated the effect of hypercapnia-induced changes in CBV on systolic CSFVPeak in anesthetized patients (n = 8). Hypercapnia (ETCO(2) = 60 mm Hg) increased systolic CSFVPeak in the aqueduct of Sylvius as compared with normocapnia (ETCO(2) = 40 mm Hg) (hypercapnia: -5.67 +/- 0.74 cm/s versus normocapnia: -3.54 +/- 0.98 cm/s). In addition to the already known decrease in systolic CSFVPeak, changes in cerebral compliance can also prompt an increase in systolic CSFVPeak. IMPLICATIONS: Magnetic resonance imaging measurements of systolic cerebrospinal fluid peak velocity (CSFVPeak) in the aqueduct of Sylvius are sensitive enough to detect even minor changes in cerebral compliance. We investigated the effect of hypercapnia-induced changes in cerebral blood volume on systolic CSFVPeak in anesthetized patients. Hypercapnia (end-tidal carbon dioxide concentration = 60 mm Hg) increased systolic CSFVPeak.

Publication Types:
PMID: 12351292 [PubMed - indexed for MEDLINE]

24: Anesth Analg 2002 Oct;95(4):940-3, table of contents Related Articles, Links
 
A comparison between anterior and posterior monitoring of neuromuscular blockade at the diaphragm: both sites can be used interchangeably.

Hemmerling TM, Schmidt J, Schurr C, Breuer G, Jacobi KE.

Department of Anesthesiology, University of Montreal, Canada. thomashemmerling@hotmail.com

We present a novel site of monitoring neuromuscular blockade of the diaphragm at the patient's back. After the induction of anesthesia, 12 patients were orotracheally intubated. Two Ag/AgCl-electrodes were attached at the right seventh or eighth intercostal space between the midclavicular and anterior axillary line; two Ag/AgCl-electrodes were paravertebrally attached on the right side lateral to vertebrae T12-L1 or L1-2. Two Ag/AgCl-skin-electrodes were placed over the right thenar area for an electromyography recording of the adductor pollicis (AP) muscle, and two Ag/AgCl-skin-electrodes were used to stimulate the ulnar nerve. Onset and offset of neuromuscular blockade after rocuronium 0.6 mg/kg were determined, and significant differences between diaphragm and AP muscle and agreement between the two methods were determined. Mean maximum block was more than 96% at all sites. Lag time, onset 50, and onset time were not significantly different between the diaphragm and the AP. However, time to reach 25% of control twitch was significantly longer at the AP muscle than at the diaphragm (P < 0.001). The difference of the means and limits of agreement between the anterior and the posterior site of diaphragmatic monitoring were 0 +/- 11 s, 3 +/- 9 s, 0 +/- 19 s, and -2% +/- 5% for lag, onset 50, onset time, and peak effect, respectively, and -2 +/- 2 min for the time to reach 25% of control twitch of neuromuscular blockade. We conclude that anterior and posterior diaphragmatic monitoring can be used interchangeably to determine neuromuscular blockade after rocuronium. IMPLICATIONS: We present a novel site of monitoring neuromuscular blockade of the diaphragm at the patient's back, which shows good agreement with the conventional anterior site at the seventh or eighth intercostal space.

Publication Types:
PMID: 12351272 [PubMed - indexed for MEDLINE]

25: Anesth Analg 2002 Oct;95(4):923-9, table of contents Related Articles, Links
 
Propofol in a medium- and long-chain triglyceride emulsion: pharmacological characteristics and potential beneficial effects.

Theilen HJ, Adam S, Albrecht MD, Ragaller M.

Department of Anesthesiology and Intensive Care Medicine, University Hospital of the Technical University of Dresden, Dresden, Germany. theilen@rcs.urz.tu-dresden.de

Hypertriglyceridemia is a possible unwanted effect during long-term propofol sedation while using a formulation containing long-chain triglycerides (LCT) from soybean oil. The use of propofol formulated in a solvent consisting of medium-chain triglycerides (MCT) and LCT might reduce the risk. Because a new solvent may affect the pharmacological profile of propofol, in this prospective, randomized, controlled, and double-blinded study we compared the pharmacodynamic and kinetic characteristics of propofol diluted in MCT/LCT fat solution with those of propofol formulated in LCT fat emulsion. In addition, serum triglyceride levels were measured during and after the administration of both drugs. Thirty patients likely to require mechanical ventilation over at least 48 h were randomized to receive either propofol 2% MCT/LCT (Group 1) or propofol 2% LCT (Group 2). Infusion rates of propofol (2.34 +/- 0.83 mg. kg(-1). h(-1) in Group 1 versus 2.31 +/- 0.6 mg. kg(-1). h(-1) in Group 2), the plasma propofol concentrations during infusion (0.95 +/- 0.53 versus 0.98 +/- 0.32 micro g/mL), and the concentrations and arousal behavior after discontinuation of the drug did not show significant differences. Plasma triglyceride concentrations during sedation did not differ between the groups, whereas there was a tendency toward a more rapid triglyceride elimination in Group 1 after termination of the propofol administration. IMPLICATIONS: Propofol diluted in an emulsion of medium- and long chain-triglycerides shows equivalent pharmacological properties during long-term sedation compared with its hitherto well known formulation containing long-chain triglycerides only. In addition, potential favorable effects on the plasma triglyceride profile could be found.

Publication Types:
PMID: 12351269 [PubMed - indexed for MEDLINE]

26: Anesth Analg 2002 Oct;95(4):874-5, table of contents Related Articles, Links
 
Left ventricular mass in a patient with Carney's complex.

Szokol JW, Franklin M, Murphy GS, Wynnychenko TM, Sener SF.

Department of Anesthesiology, Evanston Northwestern Healthcare, Evanston, Illinois 60201, USA. szokol@nwu.edu

IMPLICATIONS: Carney's complex is characterized by cardiac myxomas, adrenocortical disease, growth hormone-secreting adenomas, and other types of tumors. Its prevalence and incidence are unknown. The anesthesiologist must examine the patient or order tests to exclude cardiac tumors, signs of excess cortisol secretion, acromegaly, and possible peripheral nerve root involvement.

PMID: 12351260 [PubMed - indexed for MEDLINE]

27: Anesth Analg 2002 Oct;95(4):851-7, table of contents Related Articles, Links
 
Beta-adrenergic stimulation restores oxygen extraction reserve during acute normovolemic hemodilution.

Crystal GJ, Salem MR.

Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, Illinois 60657, USA. gcrystal@uic.edu

Compensatory increases in oxygen extraction (EO(2)) during acute normovolemic hemodilution (ANH) have the effect of decreasing tissue oxygen tension values, thus increasing the threat of tissue hypoxia. We hypothesized that if the beta-adrenergic agonist isoproterenol (ISOP) could augment cardiac output (CO) during ANH, it could reverse the increases in EO(2) and restore the margin of safety for tissue oxygenation. Studies were performed in seven anesthetized (isoflurane) dogs. CO was measured by using thermodilution, and regional blood flow (RBF) was measured by using radioactive microspheres. Systemic oxygen delivery (DO(2)), oxygen consumption (OV0312;O(2)), and EO(2), as well as regional DO(2), were calculated. Measurements were obtained under the following conditions in each dog: 1) baseline-1, 2) ISOP (0.1 micro g. kg(-1). min(-1) IV), 3) baseline-2, 4) ANH, and 5) ISOP during ANH. Hematocrit was 45% +/- 3% under baseline conditions and 18% +/- 3% during ANH. Before ANH, ISOP caused parallel increases in CO and systemic DO(2), which, in the presence of an unchanged OV0312;O(2), reduced EO(2). RBF increased in myocardium and spleen, decreased in pancreas, and did not change in brain, spinal cord, or other tissues. ANH caused increases in CO, which were insufficient to offset the decrease in arterial oxygen content, and thus systemic DO(2) declined; systemic OV0312;O(2) was maintained by an increase in EO(2). ANH-related increases in RBF maintained DO(2) in myocardium, brain, duodenum, and pancreas, whereas DO(2) declined in kidney and spleen. ISOP during ANH increased CO and systemic DO(2), which returned systemic EO(2) to baseline, and it increased RBF in myocardium, kidney, duodenum, and spleen. We conclude that 1) beta-adrenergic stimulation with ISOP restored the systemic EO(2) reserve during ANH, without apparent adverse effects in the individual body tissues, and that 2) the use of inotropic drugs, such as ISOP, may extend the limit to which hematocrit can be reduced safely during ANH. IMPLICATIONS: By restoring the oxygen extraction reserve, isoproterenol and other inotropic drugs can enhance the margin of safety and extend the limit to which hematocrit can be reduced safely during acute normovolemic hemodilution. The use of this approach will depend on the degree of hemodilution, the extent of mixed venous oxygen desaturation, and whether increases in cardiac output are possible or desirable.

PMID: 12351256 [PubMed - indexed for MEDLINE]

28: Anesth Analg 2002 Oct;95(4):835-43, table of contents Related Articles, Links
 
Preload index: pulmonary artery occlusion pressure versus intrathoracic blood volume monitoring during lung transplantation.

Della Rocca G, Costa GM, Coccia C, Pompei L, Di Marco P, Pietropaoli P.

Istituto di Anestesiologia e Rianimazione, University of Rome "La Sapienza," Azienda Ospedaliera Policlinico Umberto I, Rome, Italy. giorgio.dellaroca@uniroma1.it

In this study, during lung transplantation, we analyzed a conventional preload index, the pulmonary artery occlusion pressure (PAOP), and a new preload index, the intrathoracic blood volume index (ITBVI), derived from the single-indicator transpulmonary dilution technique (PiCCO System), with respect to stroke volume index (SVIpa). We also evaluated the relationships between changes (Delta) in ITBVI and PAOP and DeltaSVIpa during lung transplantation. The reproducibility and precision of all cardiac index measurements obtained with the transpulmonary single-indicator dilution technique (CIart) and with the pulmonary artery thermodilution technique (CIpa) were also determined. Measurements were made in 50 patients monitored with a pulmonary artery catheter and with a PiCCO System at six stages throughout the study. Changes in the variables were calculated by subtracting the first from the second measurement (Delta(1)) and so on (Delta(1) to Delta(5)). The linear correlation between ITBVI and SVIpa was significant (r(2)=0.41; P < 0.0001), whereas PAOP poorly correlated with SVIpa (r(2) = -0.01). Changes in ITBVI correlated with changes in SVIpa (Delta(1), r(2) = 0.30; Delta(2), r(2) = 0.57; Delta(4), r(2) = 0.26; and Delta(5), r(2) = 0.67), whereas PAOP failed. The mean bias between CIart and CIpa was 0.15 l. min(-1). m(-2) (1.37). In conclusion, ITBVI is a valid indicator of cardiac preload and may be superior to PAOP in patients undergoing lung transplantation. IMPLICATIONS: The assessment of intrathoracic blood volume index (ITBVI) by the transpulmonary single-indicator technique is a useful tool in lung transplant patients, providing a valid index of cardiac preload that may be superior to pulmonary artery occlusion pressure. However, more prospective, randomized studies are necessary to evaluate the role and limitations of this technique.

Publication Types:
PMID: 12351254 [PubMed - indexed for MEDLINE]

29: Anesth Analg 2002 Oct;95(4):828-34, table of contents Related Articles, Links
 
Correction of ionized plasma magnesium during cardiopulmonary bypass reduces the risk of postoperative cardiac arrhythmia.

Wilkes NJ, Mallett SV, Peachey T, Di Salvo C, Walesby R.

Department of Anaesthesia and Cardiothoracic Surgery, Royal Free Hospital, London, United Kingdom. Nicholas.Wilkes@rfh.nthames.nhs.uk

We conducted this randomized controlled trial to determine whether the intraoperative measurement and correction of ionized plasma magnesium can reduce the risk of cardiac arrhythmia after cardiopulmonary bypass. Eighty-five patients presenting for coronary artery bypass grafting were randomly assigned either to the magnesium-corrected group, which received magnesium sulfate on the basis of measured levels of ionized plasma magnesium (n = 43), or to the control group, in which magnesium levels were identified but not corrected (n = 42). Ionized magnesium was determined with an ion-selective electrode with minimal delay, and further samples were taken for laboratory analysis of total plasma magnesium. All patients had Holter electrocardiogram monitoring for 72 h after surgery. Total hypomagnesemia (45 patients; 53% of all patients) was more common than ionized hypomagnesemia (11 patients; 13%) before cardiopulmonary bypass. Both total and ionized magnesium levels declined further during the course of cardiopulmonary bypass in the control group. The incidence of ventricular tachycardia in the first 24 h was less frequent in the magnesium-corrected group (3 patients; 7%) than the control group (12 patients, 30%; P < 0.01). Patients in the magnesium-corrected group were more likely to display continuous sinus rhythm (Lown Grade 0) in the first 24 h (14 patients; 34%) than patients in the control group (2 patients, 5%; P < 0.001). Our results suggest that the intraoperative correction of ionized magnesium is associated with a reduction in postoperative ventricular arrhythmia in cardiac surgical patients. IMPLICATIONS: In this study the correction of ionized plasma magnesium during cardiopulmonary bypass was guided by measurements from an ion-selective electrode. This intervention resulted in a reduction in the incidence of postoperative ventricular tachycardia and an increased frequency of continuous sinus rhythm. Ion-selective electrodes constitute a convenient near-patient test, providing a basis for the targeted replacement of ionized plasma magnesium.

Publication Types:
PMID: 12351253 [PubMed - indexed for MEDLINE]

30: Anesth Analg 2002 Oct;95(4):805-12, table of contents Related Articles, Links
 
Remifentanil, fentanyl, and cardiac surgery: a double-blinded, randomized, controlled trial of costs and outcomes.

Myles PS, Hunt JO, Fletcher H, Watts J, Bain D, Silvers A, Buckland MR.

Department of Anaesthesia & Pain Management, Alfred Hospital, Prahran, Victoria, Australia. p.myles@alfred.org.au

Remifentanil may be beneficial in patients undergoing coronary artery bypass graft surgery, by promoting hemodynamic stability, reducing drug requirements, and attenuating the neurohumoral "stress response." We enrolled 77 cardiac surgical patients in a double-blinded, randomized trial and randomly allocated them to one of three groups: remifentanil infusion at 0.83 micro g. kg(-1). min(-1) (Group R); fentanyl bolus, small dose, at 12 micro g/kg (Group FLD); and fentanyl bolus, moderate dose, at 24 micro g/kg (Group FMD). We found a significant difference in the median time to tracheal extubation: Group FLD, 6.5 h; Group R, 7.3 h; and Group FMD, 9.7 h (P = 0.025). Group R patients had similar times to those of Groups FLD (P = 0.14) and FMD (P = 0.30). Group FLD patients had a longer length of hospital stay (P = 0.030). Patients in Group R had a significantly infrequent rate of hypertension but a frequent rate of hypotension (P < 0.01). The urinary cortisol excretion was larger in Group FLD patients (P < 0.0005), and urine flow was smaller (P < 0.0005). Remifentanil was associated with a propofol dose reduction (P = 0.0005) and a concomitant higher bispectral index (P = 0.032). Three Group FLD patients, but none in groups FMD and R, had postoperative myocardial infarctions (P = 0.032). Remifentanil has larger drug acquisition costs but does not increase the total hospital costs associated with cardiac surgery. IMPLICATIONS: Remifentanil did not significantly reduce the duration of tracheal intubation after cardiac surgery. Remifentanil, when compared with fentanyl (total doses of approximately 15 and 28 micro g/kg), blunts the hypertensive responses associated with cardiac surgery but is associated with more hypotension; when compared with fentanyl 15 micro g/kg, remifentanil reduces cortisol excretion. Larger-dose opioids (remifentanil 0.85 micro g. kg(-1). min(-1) or fentanyl 28 micro g/kg) were associated with a decreased rate of myocardial infarction after cardiac surgery.

Publication Types:
PMID: 12351249 [PubMed - indexed for MEDLINE]

31: Anesthesiology 2002 Nov;97(5):1318-21 Related Articles, Links
 
Differential effects of volatile anesthetics on hepatic heme oxygenase-1 expression in the rat.

Hoetzel A, Geiger S, Loop T, Welle A, Schmidt R, Humar M, Pahl HL, Geiger KK, Pannen BH.

Department of Anesthesiology and Critical Care Medicine, University of Freiburg, Germany.

PMID: 12411824 [PubMed - indexed for MEDLINE]

32: Anesthesiology 2002 Nov;97(5):1309-10 Related Articles, Links
 
Permanent postoperative vision loss associated with expansion of intraocular gas in the presence of a nitrous oxide-containing anesthetic.

Seaberg RR, Freeman WR, Goldbaum MH, Manecke GR Jr.

Department of Anesthesiology, University of California, San Diego, USA. rseaberg@ucsd.edu

PMID: 12411820 [PubMed - indexed for MEDLINE]

33: Anesthesiology 2002 Nov;97(5):1305-8 Related Articles, Links
 
Visual loss after use of nitrous oxide gas with general anesthetic in patients with intraocular gas still persistent up to 30 days after vitrectomy.

Vote BJ, Hart RH, Worsley DR, Borthwick JH, Laurent S, McGeorge AJ.

Department of Anaesthesia, Auckland Hospital, New Zealand.

PMID: 12411819 [PubMed - indexed for MEDLINE]

34: Anesthesiology 2002 Nov;97(5):1281-94 Related Articles, Links

Comment in:  
Fatigue in anesthesia: implications and strategies for patient and provider safety.

Howard SK, Rosekind MR, Katz JD, Berry AJ.

Patient Safety Center of Inquiry, Anesthesia Service, VA Palo Alto Health Care System, Department of Anesthesia, Stanford University School of Medicine, California 94304, USA. showard@stanford.edu

Publication Types:
PMID: 12411816 [PubMed - indexed for MEDLINE]

35: Anesthesiology 2002 Nov;97(5):1274-80 Related Articles, Links

Comment in:  
Major complications of regional anesthesia in France: The SOS Regional Anesthesia Hotline Service.

Auroy Y, Benhamou D, Bargues L, Ecoffey C, Falissard B, Mercier F, Bouaziz H, Samii K.

Departement d' Anesthesie-Reanimation, Hopital d' Instruction des Armees Percy, Clamart, France. Yves.Auroy@wanadoo.fr

BACKGROUND: Several previous surveys have estimated the rate of major complications that occur after regional anesthesia. However, because of the increase in the use of regional anesthesia in recent years and because of the introduction of new techniques, reappraisal of the incidence and the characteristics of major complications is useful. METHODS: All French anesthesiologists were invited to participate in this 10-month prospective survey based on (1) voluntary reporting of major complications related to regional anesthesia occurring during the study period using a telephone hotline service available 24 h a day and managed by three experts, and (2) voluntary reporting of the number and type of regional anesthesia procedures performed using pocket booklets. The service was free of charge for participants. RESULTS: The participants (n = 487) reported 56 major complications in 158,083 regional anesthesia procedures performed (3.5/10,000). Four deaths were reported. Cardiac arrest occurred after spinal anesthesia (n = 10; 2.7/10,000) and posterior lumbar plexus block (n = 1; 80/10,000). Systemic local anesthetic toxicity consisted of seizures only, without cardiac toxicity. Lidocaine spinal anesthesia was associated with more neurologic complications than bupivacaine spinal anesthesia (14.4/10,000 vs. 2.2/10,000). Most neurologic complications were transient. Among 12 that occurred after peripheral nerve blocks, 9 occurred in patients in whom a nerve stimulator had been used. CONCLUSION: This prospective survey based on a free hotline permanent telephone service allowed us to estimate the incidence of major complications related to regional anesthesia and to provide a detailed analysis of these complications.

PMID: 12411815 [PubMed - indexed for MEDLINE]

36: Anesthesiology 2002 Nov;97(5):1234-44 Related Articles, Links
 
Long-term pain and activity during recovery from major thoracotomy using thoracic epidural analgesia.

Ochroch EA, Gottschalk A, Augostides J, Carson KA, Kent L, Malayaman N, Kaiser LR, Aukburg SJ.

Department of Anesthesia, University of Pennsylvania Medical Center, Philadelphia, USA.

BACKGROUND: Pain following thoracotomy can persist for years with an undetermined impact on quality of life. Factors hypothesized to modulate this painful experience include analgesic regimen, gender, and type of incision. METHODS: A total of 157 generally healthy patients of both genders scheduled for segmentectomy, lobectomy, or bilobectomy through a posterolateral or muscle-sparing incision were randomly assigned to receive thoracic epidural analgesia initiated prior to incision or at the time of rib approximation. Pain and activity scores were obtained 4, 8, 12, 24, 36, and 48 weeks after surgery. RESULTS: Overall, there were no differences in pain scores between the control and intervention groups during hospitalization (P >or= 0.165) or after discharge (P>or= 0.098). The number of patients reporting pain 1 yr following surgery (18 of 85; 21.2%) was not significantly different (P = 0.122) from the number reporting preoperative pain (15 of 120; 12.5%). During hospitalization, women reported greater pain than men (worst pain, P= 0.007; average pain, P= 0.016). Women experienced fewer supraventricular tachydysrhythmias (P = 0.013) and were thus discharged earlier (P = 0.002). After discharge women continued to report greater discomfort than men (P <or= 0.016), but did not differ from men in their level of physical activity (P = 0.241). CONCLUSIONS: Initiation of thoracic epidural analgesia prior to incision or the use of a muscle-sparing incision did not significantly impact pain or physical activity. Although women reported significantly greater pain during hospitalization and after discharge, they experienced fewer complications, were more likely to be discharged from the hospital sooner, and were just as active after discharge as men.

Publication Types:
PMID: 12411810 [PubMed - indexed for MEDLINE]

37: Anesthesiology 2002 Nov;97(5):1209-17 Related Articles, Links
 
Biphasic effects of isoflurane on the cardiac action potential: an ionic basis for anesthetic-induced changes in cardiac electrophysiology.

Suzuki A, Aizawa K, Gassmayr S, Bosnjak ZJ, Kwok WM.

Department of Anesthesiology, Medical College of Wisconsin, Milwaukee 53226, USA.

BACKGROUND: The mechanism underlying isoflurane modulation of cardiac electrophysiology is not well understood. In the present study, the authors investigated the effects of isoflurane on the cardiac action potential (AP) characteristics. The results were correlated to modulation of the L-type calcium (I(Ca,L)), the delayed-rectifier potassium (I(Kdr)), and the inward-rectifier potassium (I(Kir)) currents. METHODS: Single ventricular myocytes were enzymatically isolated from guinea pig hearts. The current clamp and whole cell voltage clamp configurations of the patch clamp technique were used to monitor the cardiac AP and ionic currents, respectively. A dynamic AP voltage protocol that mimicked changes in membrane potential during an AP was used to monitor the I(Ca,L), I(Kdr) and I(Kir). RESULTS: Isoflurane produced a concentration-dependent, biphasic effect on the AP duration (APD). At 0.6 mm (1.26 vol%), isoflurane significantly increased APD50 and APD90 by 50.0 +/- 7.6% and 48.9 +/- 7.2%, respectively (P < 0.05; n = 6). At 1.0 mm (2.09 vol%), isoflurane had no significant effect on APD (n = 6). In contrast, at 1.8 mm (3.77 vol%), isoflurane decreased APD50 and APD90 by 38.3 +/- 5.4% and 32.2 +/- 5.5%, respectively (P < 0.05; n = 7). The inhibitory effects of isoflurane on I(Kdr) chord conductance were greater than those on I(Ca,L) (P < 0.05; n = 6/group). Both I(Ca,L) inactivation and I(Kdr) activation kinetics were accelerated by isoflurane. Isoflurane had no significant effects on I(Kir) chord conductance (n = 6). CONCLUSION: At the lower anesthetic concentration, the prolongation of the APD may be the result of the dominant inhibitory effects of isoflurane on I(Kdr). At the higher concentration, the shortening of the APD may be caused by the inhibitory effects on I (Ca,L) combined with the isoflurane-induced acceleration of I(Ca,L) inactivation kinetics. Because I(Kdr) is significantly inhibited by isoflurane, I(Kir) appears to be the major repolarizing current, which is minimally affected by isoflurane.

PMID: 12411807 [PubMed - indexed for MEDLINE]

38: Anesthesiology 2002 Nov;97(5):1178-88 Related Articles, Links
 
Transmission through the dorsal spinocerebellar and spinoreticular tracts: wakefulness versus thiopental anesthesia.

Soja PJ, Taepavarapruk N, Pang W, Cairns BE, McErlane SA, Fragoso MC.

Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, Canada. soja@exchange.ubc.ca

BACKGROUND: Most of what is known regarding the actions of injectable barbiturate anesthetics on the activity of lumbar sensory neurons arises from experiments performed in acute animal preparations that are exposed to invasive surgery and neural depression caused by coadministered inhalational anesthetics. Other parameters such as cortical synchronization and motor ouflow are typically not monitored, and, therefore, anesthetic actions on multiple cellular systems have not been quantitatively compared. METHODS: The activities of antidromically identified dorsal spinocerebellar and spinoreticular tract neurons, neck motoneurons, and cortical neurons were monitored extracellularly before, during, and following recovery from the anesthetic state induced by thiopental in intact, chronically instrumented animal preparations. RESULTS: Intravenous administration of 15 mg/kg, but not 5 mg/kg, of thiopental to awake cats induced general anesthesia that was characterized by 5-10 min of cortical synchronization, reflected as large-amplitude slow-wave events and neck muscle atonia. However, even though the animal behaviorally began to reemerge from the anesthetic state after this 5-10-min period, neck muscle (neck motoneuron) activity recovered more slowly and remained significantly suppressed for up to 23 min after thiopental administration. The spontaneous activity of both dorsal spinocerebellar and spinoreticular tract neurons was maximally suppressed 5 min after administration but remained significantly attenuated for up to 17 min after injection. Peripheral nerve and glutamate-evoked responses of dorsal spinocerebellar and spinoreticular tract neurons were particularly sensitive to thiopental administration and remained suppressed for up to 20 min after injection. CONCLUSIONS: These results demonstrate that thiopental administration is associated with a prolonged blockade of motoneuron output and sensory transmission through the dorsal spinocerebellar and spinoreticular tracts that exceeds the duration of general anesthesia. Further, the blockade of glutamate-evoked neuronal responses indicates that these effects are due, in part, to a local action of the drug in the spinal cord. The authors suggest that this combination of lumbar sensory and motoneuron inhibition underlies the prolonged impairment of reflex coordination observed when thiopental is used clinically.

PMID: 12411804 [PubMed - indexed for MEDLINE]

39: Anesthesiology 2002 Nov;97(5):1137-41 Related Articles, Links
 
Intravenous magnesium sulfate administration reduces propofol infusion requirements during maintenance of propofol-N2O anesthesia: part I: comparing propofol requirements according to hemodynamic responses: part II: comparing bispectral index in control and magnesium groups.

Choi JC, Yoon KB, Um DJ, Kim C, Kim JS, Lee SG.

Department of Anesthesiology, Yonsei University Wonju College of Medicine, Kwangwon-Do, South Korea.

BACKGROUND: The authors investigated whether an intravenous administration of magnesium sulfate reduces propofol infusion requirements during maintenance of propofol-N2O anesthesia. METHODS: Part I study: 54 patients undergoing total abdominal hysterectomy were randomly divided into two groups (n = 27 per group). The patients in the control group received 0.9% sodium chloride solution, whereas the patients in the magnesium group received magnesium (50 mg/kg as a bolus, then 8 mg x kg(-1) x h(-1)). To maintain mean arterial blood pressure (MAP) and heart rate (HR) at baseline value, the propofol infusion rate was changed when the MAP or the HR changed. The amount of propofol infused excluding the bolus dosage was divided by patient's body weight and total infusion time. Part II study: Another 20 patients were randomly divided into two groups (n = 10 per group). When the MAP and HR had been maintained at baseline value and the propofol infusion rate had been maintained at 80 microg x kg(-1) x min(-1) (magnesium group) and 160 microg x kg(-1) x min(-1) (control group), bispectral index (BIS) values were measured. RESULTS: Part I: The mean propofol infusion rate in the magnesium group (81.81 +/- 13.09 microg x kg(-1) x min(-1)) was significantly less than in the control group (167.57 +/- 47.27). Part II: BIS values in the control group (40.70 +/- 3.89) were significantly less than those in the magnesium group (57.80 +/- 7.32). CONCLUSION: Intravenous administration of magnesium sulfate reduces propofol infusion requirements. These results suggest that magnesium administration may have an effect on anesthesia or analgesia and may be a useful adjunct to propofol anesthesia.

Publication Types:
PMID: 12411798 [PubMed - indexed for MEDLINE]

40: Anesthesiology 2002 Nov;97(5):1082-92 Related Articles, Links
 
Concentration-effect relation of succinylcholine chloride during propofol anesthesia.

Roy JJ, Donati F, Boismenu D, Varin F.

Faculte de Pharmacie, Departement d'Anesthesiologie, Universite de Montreal, Quebec, Canada.

BACKGROUND: The pharmacokinetics and pharmacodynamics of succinylcholine were studied simultaneously in anesthetized patients to understand why the drug has a rapid onset and short duration of action. A quantitative model describing the concentration-effect relation of succinylcholine was proposed. The correlation between hydrolysis in plasma and elimination was also examined. METHODS: Before induction of anesthesia, blood was drawn for analysis in seven adults. Anesthesia was induced with propofol and remifentanil. Single twitch stimulation was applied at the ulnar nerve every 10 s, and the force of contraction of the adductor pollicis was measured. Arterial blood was drawn frequently after succinylcholine injection to characterize the front-end kinetics. Plasma concentrations were measured by mass spectrometry, and pharmacokinetic parameters were derived using compartmental and noncompartmental approaches. Pharmacokinetic-pharmacodynamic relations were estimated. RESULTS: The mean degradation rate constant in plasma (1.07 +/- 0.49 min(-1)) was not different from the elimination rate constant (0.97 +/- 0.30 min(-1)), and an excellent correlation (r2 = 0.94) was observed. Total body clearance derived using noncompartmental (37 +/- 7 ml x min(-1) x kg(-1)) and compartmental (37 +/- 9 ml x min(-1) x kg(-1)) approaches were similar. The plasma-effect compartment equilibration rate constant (k(eo)) was 0.058 +/- 0.026 min(-1), and the effect compartment concentration at 50% block was 734 +/- 211 ng/ml. CONCLUSION: Succinylcholine is a low-potency drug with a very fast clearance that equilibrates relatively slowly with the effect compartment. Its disappearance is greatly accountable by a rapid hydrolysis in plasma.

PMID: 12411790 [PubMed - indexed for MEDLINE]

41: Anesthesiology 2002 Nov;97(5):1050-1 Related Articles, Links

Comment on:  
Fact and fantasy about sleep and anesthesiology.

Lydic R.

Publication Types:
PMID: 12411785 [PubMed - indexed for MEDLINE]

42: Anesthesiology 2002 Nov;97(5):5A Related Articles, Links

Comment on:  
Postoperative sleeping patterns tracked in children undergoing outpatient surgery.

Henkel G.

Publication Types:
PMID: 12411782 [PubMed - indexed for MEDLINE]

43: Anesthesiology 2002 Oct;97(4):1038-9; discussion 1039 Related Articles, Links

Comment on:  
Acupuncture for postoperative nausea and vomiting prophylaxis: where's the point?

Cohn AI.

Publication Types:
PMID: 12357192 [PubMed - indexed for MEDLINE]

44: Anesthesiology 2002 Oct;97(4):1038; discussion 1038 Related Articles, Links

Comment on:  
Amsorb causes no less carbon monoxide formation than either "new" or "classic" sodalime.

Lemmens HJ.

Publication Types:
PMID: 12357191 [PubMed - indexed for MEDLINE]

45: Anesthesiology 2002 Oct;97(4):1037; discussion 1037 Related Articles, Links

Comment on:  
Old lessons forgotten.

Appleyard RW.

Publication Types:
PMID: 12357190 [PubMed - indexed for MEDLINE]

46: Anesthesiology 2002 Oct;97(4):1035; discussion 1035 Related Articles, Links

Comment on:  
Vecuronium sensitivity in part due to acute use of phenytoin.

Gronert GA.

Publication Types:
PMID: 12357188 [PubMed - indexed for MEDLINE]

47: Anesthesiology 2002 Oct;97(4):1029; discussion 1029-31 Related Articles, Links
 
Regional techniques and length of hospital stay after abdominal aortic surgery.

Amar D.

Publication Types:
PMID: 12357185 [PubMed - indexed for MEDLINE]

48: Anesthesiology 2002 Oct;97(4):1007-8 Related Articles, Links
 
Tracheal tear caused by extubation of a double-lumen tube.

Benumof JL, Wu D.

Department of Anesthesiology, University of California San Diego Medical Center, 92103-8812, USA. jbenumof@ucsd.edu

PMID: 12357171 [PubMed - indexed for MEDLINE]

49: Anesthesiology 2002 Oct;97(4):981-8 Related Articles, Links
 
PACU bypass after outpatient knee surgery is associated with fewer unplanned hospital admissions but more phase II nursing interventions.

Williams BA, Kentor ML, Williams JP, Vogt MT, DaPos SV, Harner CD, Fu FH.

Anesthesiology, Department of Same-Day Surgical Services, University of Pittsburgh Medical Center, Pennsylvania 15261, USA. williamsba@anes.upmc.edu

BACKGROUND: The authors recently proposed a recovery scoring system for outpatients receiving regional anesthesia (RA) or general anesthesia (GA). This scoring system was designed to allow qualifying patients to be directly routed to the phase II (step-down) recovery unit instead of the traditional postanesthesia care unit (PACU). We report PACU bypass rates using these criteria, and the extent to which PACU bypass was associated with (1) required nursing interventions in the step-down recovery unit, and (2) successful same-day discharge. METHODS: Day-of-surgery outcomes were studied for 894 outpatients undergoing outpatient sports medicine surgery on the lower extremity. We determined PACU-bypass rates, nursing interventions in the step-down recovery unit for common symptoms, and unplanned hospital admissions. Using logistic regression, we analyzed step-down nursing interventions based on PACU requirement versus PACU bypass, and anesthesia techniques used (GA vs. not, peripheral nerve blocks vs. not). RESULTS: Eighty-seven percent (778/894) of all patients bypassed PACU. Of PACU-bypass patients, 241/778 (31%) required step-down nursing interventions. Of patients requiring PACU, only 19/116 (16%) required additional interventions in step-down (P < 0.001). PACU-bypass patients were almost three times more likely (odds ratio 2.9,P < 0.001) to require at least one nursing intervention in the step-down unit, when compared with patients requiring PACU. Fewer unplanned admissions were required by patients who bypassed PACU (odds ratio = 0.3,P = 0.007). CONCLUSIONS: For outpatient lower extremity surgery, applying our PACU-bypass criteria led to an 87% PACU bypass rate with no reportable adverse events.

Publication Types:
PMID: 12357168 [PubMed - indexed for MEDLINE]

50: Anesthesiology 2002 Oct;97(4):959-65 Related Articles, Links
 
Continuous popliteal sciatic nerve block for postoperative pain control at home: a randomized, double-blinded, placebo-controlled study.

Ilfeld BM, Morey TE, Wang RD, Enneking FK.

Department of Anesthesiology, University of Florida College of Medicine, Gainesville, 32610, USA.

BACKGROUND: This randomized, double-blinded, placebo-controlled study investigated the efficacy of patient-controlled regional analgesia using a sciatic perineural catheter in the popliteal fossa and a portable infusion pump for outpatients having moderately painful, lower extremity orthopedic surgery. METHODS: Preoperatively, patients (n = 30) received a sciatic nerve block and perineural catheter in the popliteal fossa. Postoperatively, patients were discharged with both oral opioids and a portable infusion pump delivering study solution (0.2% ropivacaine or 0.9% saline) via the catheter for 3 days. Investigators and patients were blinded to random group assignment. Daily end-points included pain scores, opioid use and side effects, sleep quality, and symptoms of catheter- or local anesthetic-related complications. RESULTS: Ropivacaine (n = 15) infusion significantly reduced pain compared with saline (n = 15) infusion ( < 0.001). For example, the average pain at rest (scale: 0-10) on postoperative day 1 (median, 25th -75th percentile) was 4.0 (3.5-5.5) for the saline group, versus 0.0 (0.0-0.0) for the ropivacaine group (P < 0.001). Oral opioid use and related side effects were significantly decreased in the ropivacaine group. For example, on postoperative day 1, median tablet consumption was 8.0 (5.0-10.0) and 0.0 (0.0-0.0) for the saline and ropivacaine groups, respectively (P < 0.001). Sleep disturbance scores were more than 10-fold greater for saline administration than for ropivacaine infusion (P < 0.001). Overall satisfaction was significantly greater in the ropivacaine group. Other than two inadvertent catheter dislodgements, no catheter- or local anesthetic-related complications occurred. CONCLUSIONS: After moderately painful orthopedic surgery of the lower extremity, ropivacaine infusion using a portable mechanical pump and a popliteal sciatic perineural catheter at home decreased pain, opioid use and related side effects, sleep disturbances, and improved overall satisfaction.

Publication Types:
PMID: 12357165 [PubMed - indexed for MEDLINE]