Volume 3, Issue 7 S A M B A T A L K S - PAGE 3 December, 2003

FROM THE LITERATURE: - TOP


ANESTHESIA AND ANALGESIA - TOP

The Use of a Continuous Popliteal Sciatic Nerve Block After Surgery Involving the Foot and Ankle: Does It Improve the Quality of Recovery?
Paul F. White, PhD MD, FANZCA, Tijani Issioui, MD, Gary D. Skrivanek, MD, John S. Early, MD, and Cynthia Wakefield
Anesth Analg 2003;97:1303-1309

Popliteal sciatic nerve block is a commonly used technique for surgery involving the foot and ankle. However, pain can be difficult to control as the local anesthetic block wears off. Therefore, we hypothesized that extending the block by using a continuous infusion of bupivacaine (0.25%) would provide improved pain management and might facilitate the recovery process after foot or ankle surgery. In this randomized, double-blinded, placebo-controlled study, 24 consenting patients undergoing foot or ankle surgery with a standardized general anesthetic technique were studied. Before surgery, a popliteal sciatic nerve block was performed in all patients with an 18-gauge Tuohy epidural needle and a peripheral nerve stimulator. After injection of bupivacaine 0.25% 30 mL and placement of a 20-gauge catheter, patients were randomly assigned to receive either 0.9% saline (control) or bupivacaine 0.25% at a constant rate of 5 mL/h for up to 48 h after surgery. An 11-point verbal rating scale (0 = no pain to 10 = worst pain imaginable) was used to assess the severity of pain. Opioid analgesic use was recorded at specific time intervals after surgery. Follow-up evaluations were performed at 24 h, 48 h, 72 h, and 1 week after surgery to assess pain scores, as well as patient satisfaction with their pain management and quality of recovery, by using a 100-point verbal rating scale (1 = highly dissatisfied to 100 = highly satisfied). In the bupivacaine group, there was a statistically significant reduction in the maximal pain scores (>50%) and in opioid use (>60%) during the postoperative period compared with the control group. Patient satisfaction with postoperative pain management (95 ± 3 versus 77 ± 13) and quality of recovery (96 ± 7 versus 83 ± 14) was significantly improved in the bupivacaine group (versus control). In addition, 40% of the patients in the bupivacaine group (versus none in the control group) were able to be discharged home on the day of surgery (P = 0.087). In conclusion, a continuous infusion of bupivacaine 0.25% decreased postoperative pain and the need for opioid analgesic rescue medication after orthopedic surgery involving the foot and ankle, leading to improved patient satisfaction and quality of recovery.
IMPLICATIONS: A continuous infusion of bupivacaine 0.25% (versus saline) at the popliteal fossa by using a simple elastomeric pump is an effective method of decreasing postoperative pain, reducing the opioid analgesic requirement, and increasing patient satisfaction with pain management after orthopedic surgery involving the foot and ankle. More importantly, the use of the continuous sciatic nerve block in the popliteal fossa facilitated an earlier discharge after lower extremity surgery.

Facial Skin Injuries Caused by Adhesive Tapes in a Patient Receiving Cosmetic Skin Exfoliants
Chau P. Wong, MB ChB, Po T. Chui, MB BS, FANZCA, and Manoj K. Karmakar, MB BS, FRCA
Anesth Analg 2003;97:1310-1311

IMPLICATIONS: We report a young woman with fragile facial skin after using cosmetics containing skin peeling agents. Removal of adhesive tapes applied to her face under general anesthesia caused patchy areas of skin loss. The complication may best be avoided by not applying adhesive tapes to the face.

Anaphylaxis During the Perioperative Period (Review)
David L. Hepner, MD, and Mariana C. Castells, MD PhD
Anesth Analg 2003;97:1381-1395

Anesthesiologists use a myriad of drugs during the provision of an anesthetic. Many of these drugs have side effects that are dose related, and some lead to severe immune-mediated adverse reactions. Anaphylaxis is the most severe immune-mediated reaction; it generally occurs on reexposure to a specific antigen and requires the release of proinflammatory mediators. Anaphylactoid reactions occur through a direct non-immunoglobulin E-mediated release of mediators from mast cells or from complement activation. Muscle relaxants and latex account for most cases of anaphylaxis during the perioperative period. Symptoms may include all organ systems and present with bronchospasm and cardiovascular collapse in the most severe cases. Management of anaphylaxis includes discontinuation of the presumptive drug (or latex) and anesthetic, aggressive pulmonary and cardiovascular support, and epinephrine. Although a serum tryptase confirms the diagnosis of an anaphylactic reaction, the offending drug can be identified by skinprick, intradermal testing, or serologic testing. Prevention of recurrences is critical to avoid mortality and morbidity.

The Effect of Intravenous Pantoprazole and Ranitidine for Improving Preoperative Gastric Fluid Properties in Adults Undergoing Elective Surgery
Dilek Memi , MD, Alparslan Turan, MD, Beyhan Karamanlioglu, MD, P nar Saral, MD, Mevlüt Türe, PhD, and Zafer Pamukçu, MD
Anesth Analg 2003;97:1360-1363

We studied pantoprazole, a new potent and fast-acting proton pump inhibitor. Its effects on preoperative gastric fluid volume and pH have not yet been determined. In this randomized, controlled trial, we examined the effects of preoperative IV pantoprazole or ranitidine on gastric pH and volume. Ninety patients (ASA status I and II, scheduled for elective surgery) were studied. One hour before surgery, patients in Group I (n = 30) were given IV saline 5 mL, those in Group II (n = 30) were given 40 mg of pantoprazole IV, and those in Group III (n = 30) were given 50 mg of ranitidine IV. A nasogastric tube was inserted immediately after anesthesia induction. Gastric contents were aspirated, and volume and pH were recorded. The pH values determined in Group I were 3.73 ± 0.82; in Group II, they were 5.30 ± 1.84; and in Group III, they were 4.80 ± 1.40. There was no statistical difference between Groups 2 and 3, but there was a significant difference between Group I and Groups 2 and 3 (P < 0.0005). The volume of the gastric contents was 28.67 ± 10.98 mL in Group I, 15.20 ± 15.52 mL in Group II, and 7.77 ± 11.17 mL in Group III. There was no statistical difference between Groups 2 and 3, but there was a statistically significant difference between Group I and Groups 2 and 3 (P < 0.0005). The proportion of patients considered "at risk" of significant lung injury should aspiration occur was 20% of Group I, 10% of Group II, and 3.3% of Group III. When statistically evaluated, there was no difference among groups. We concluded that the administration of IV pantoprazole and ranitidine 1 h before surgery is effective in reducing gastric pH and volume.
IMPLICATIONS: This randomized, controlled trial examined the effects of preoperative IV pantoprazole or ranitidine on gastric pH and volume. We concluded that IV pantoprazole and ranitidine, given 1 h before surgery, are effective in reducing gastric pH and volume.

CANADIAN JOURNAL OF ANESTHESIA - TOP

Limitations of preoperative dobutamine stress echocardiography in identifying severe left main coronary artery stenosis: a report of two cases and a brief review Calvin Thompson, MD FRCPC, Douglas Bergstrome, MD FRCPC and Joel L. Parlow, MD FRCPC MSc Canadian Journal of Anesthesia 50:933-939 (2003)

Purpose: Using case illustrations, to elucidate factors which increase the likelihood of false negative preoperative dobutamine stress echocardiography (DSE) studies in patients with severe left main coronary artery stenosis, and to provide criteria which must be met in order to ensure the accurate interpretation of these tests.
Clinical features and source: Two patients presented for elective abdominal aortic aneurysm repair within a one-month period of time. Both patients had DSE as part of their preoperative assessment, which were interpreted as normal. Nevertheless, both suffered major coronary events in the perioperative period, and both proved to have severe left main coronary artery stenosis on postoperative angiography. A narrative review is presented based on a selection of the current literature, and local experience with the technique. Some pitfalls in the interpretation of these tests are presented, along with modalities to increase their sensitivity and specificity.
Conclusion: DSE is an important and useful modality in the preoperative cardiac evaluation of patients who are unable to exercise. However the reliable interpretation of the test depends on an understanding of the limitations of the procedure.

Edrophonium effectively antagonizes neuromuscular block at the laryngeal adductors induced by rapacuronium, rocuronium and cisatracurium, but not mivacurium
Takahiro Suzuki, MD PhD, Cynthia A. Lien, MD, Matthew R. Belmont, MD, Joseph Tjan, MD and John J. Savarese, MD
Canadian Journal of Anesthesia 50:879-885 (2003)

Purpose: To examine the efficacy of antagonism of rapacuronium-, mivacurium-, rocuronium- and cisatracurium-induced neuromuscular block at the laryngeal adductors (LA).
Methods: One hundred four patients were randomly assigned to one of eight study groups. They either received rapacuronium 1.5 mg•kg^-1, mivacurium 0.25 mg•kg^-1, rocuronium 0.9 mg•kg^-1 or cisatracurium 0.15 mg•kg^-1. Patients in each treatment group either received edrophonium (0.5 mg•kg^-1) at 10% recovery of the first twitch (T1) of train-of-four (TOF) at the LA or were allowed to recover spontaneously from neuromuscular block. The effect of antagonism on speed of recovery of neuromuscular function at the LA was evaluated.
Results: The time to recovery to a TOF ratio of 0.9 at the LA, when compared to the spontaneous recovery group, was significantly shortened by the administration of edrophonium in patients receiving rapacuronium [19.2 ± 7.8 vs 26.2 ± 4.9 (mean ± SD) min], rocuronium (24.7 ± 14.3 vs 44.4 ± 13.0 min) and cisatracurium (24.2 ± 5.7 vs 35.1 ± 7.6 min). Edrophonium administration did not shorten complete recovery from mivacurium-induced block (15.7 ± 8.0 vs 17.6 ± 6.1 min).
Conclusion: Recovery from rapacuronium-, rocuronium- or cisatracurium- induced neuromuscular block to a TOF ratio of 0.9 as measured at the LA was shortened by the administration of edrophonium, when compared to spontaneous recovery.

ACTA ANAESTHESIOLOGICA SCANDINAVICA - TOP

Cognitive dysfunction after minor surgery in the elderly
J. Canet, J. Raeder, L. S. Rasmussen, M. Enlund, H. M. Kuipers, C. D. Hanning, J. Jolles, K. Korttila, V. D. Siersma, C. Dodds, H. Abildstrom, J. R. Sneyd, P. Vila, T. Johnson, L. Muñoz Corsini, J. H. Silverstein, I. K. Nielsen, J. T. Moller
Acta Anesthesiologica Scandinavica Volume 47: Issue 10, pp 1204-10

Background: Major surgery is frequently associated with postoperative cognitive dysfunction (POCD) in elderly patients. Type of surgery and hospitalization may be important prognostic factors. The aims of the study were to find the incidence and risk factors for POCD in elderly patients undergoing minor surgery.
Methods: We enrolled 372 patients aged greater than 60 years scheduled for minor surgery under general anesthesia. According to local practice, patients were allocated to either in- (199) or out-patient (173) care. Cognitive function was assessed using neuropsychological testing preoperatively and 7 days and 3 months postoperatively. Postoperative cognitive dysfunction was defined using Z-score analysis.
Results: At 7 days, the incidence (confidence interval) of POCD in patients undergoing minor surgery was 6.8% (4.3-10.1). At 3 months the incidence of POCD was 6.6% (4.1-10.0). Logistic regression analysis identified the following significant risk factors: age greater than 70 years (odds ratio [OR]: 3.8 [1.7-8.7], P = 0.01) and in- vs. out-patient surgery (OR: 2.8 [1.2-6.3], P = 0.04).
Conclusions: Our finding of less cognitive dysfunction in the first postoperative week in elderly patients undergoing minor surgery on an out-patient basis supports a strategy of avoiding hospitalization of older patients when possible

Pharmacokinetics and pharmacodynamics of mivacurium in patients phenotypically heterozygous for the usual and atypical plasma cholinesterase variants (UA)
D. Østergaard, J. Viby-Mogensen, S. N. Rasmussen, M. R. Gätke, N. A. Pedersen and L. T. Skovgaard
Acta Anaesthesiologica Scandinavica Volume 47 Issue 10 Page 1219-25

Background: Mivacurium is hydrolyzed by plasma cholinesterase (pChe). The purpose of this study was to evaluate the pharmacodynamics and the pharmacokinetics of the three isomers of mivacurium in patients phenotypically heterozygous for the usual and the atypical pChe variant (UA).
Methods: Thirty-two patients were included in a dose-response study, in which the patients received one of four doses of mivacurium. An additional bolus dose of mivacurium, to a total of 0.1 mg kg^-1, was given followed by a continuous infusion adjusted to maintain 91-99% neuromuscular block. The times to different levels of recovery following the infusion were measured using mechanomyography and train-of-four (TOF) nerve stimulation. Twelve of the patients with an estimated duration of anaesthesia of more than 90 min were (randomly) selected for the pharmacokinetic part of the study. Venous samples were taken for determination of the three isomers of mivacurium. These results were compared with results from a previous study in phenotypically normal patients (UU).
Results: The estimated ED50 and ED95 were 24 and 69 µg kg^-1, respectively. The median (range) infusion rate was 3.7 µg kg^-1 min^-1 (1.2-2.9) and the time to a TOF ratio of 0.7 was 29.8 min (16.1-44.8). The median clearances of the cis-cis, cis-trans and trans-trans isomers were 3.7, 29 and 28 ml kg^-1 min^-1, respectively. The elimination half-lives of the isomers were 45, 6.7 and 6.3 min, respectively.
Conclusion: In patients heterozygous for the usual and the atypical variant (UA), the potency of mivacurium is higher, the infusion requirements lower and the rate of spontaneous recovery prolonged, compared with phenotypically normal patients. The clearances of the active isomers are significantly lower and the elimination half-lives longer in heterozygous patients than in phenotypically normal patients (UU). The pharmacokinetics of the inactive cis-cis isomer was not affected.

Influence of total intravenous and inhalational anaesthesia on haemostasis during tympanoplasty
E. Özer, Ü. Aypar, E. Basgül
Acta Anesthesiologica Scandinavica Volume 47: Issue 10, pp 1242-7

Background: Surgical trauma leads to systemic changes in haemostasis. Haematological changes activated by surgery may become so prominent that changes caused by anaesthesia might be hidden or underestimated. Therefore, we have undertaken a prospective study to compare the behaviour of selected factors involved in the coagulation and fibrinolytic systems.
Methods: Forty healthy adult patients scheduled for otological surgery were enrolled in the study. Upon receiving informed consent, they were randomly assigned to receive either inhalational (IA) or total intravenous anaesthesia (TIVA). Platelet function (PFA100^TM), disseminated intravascular coagulopathy (DIC) panel, and generalized d-dimer (GFC) were studied during certain periods of anaesthesia to identify the changes in haemostasis.
Results: Statistically, no significant change in DIC parameters were encountered between the two groups. No statistical difference was found between the two groups in the measured coagulation parameters, but statistically GFC showed slight activation in the 1st hour of surgical intervention.
Conclusion: Presuming a minimal traumatic effect of surgical procedure on the determined variables, we conclude that different anaesthetic techniques have a negligible effect on platelet activation and fibrinolysis. The clinical relevance of coagulation activation and fibrinolysis during different anaesthetic techniques remains to be investigated.

BRITISH JOURNAL OF ANAESTHESIA - TOP

Patient well-being after general anaesthesia: a prospective, randomized, controlled multi-centre trial comparing intravenous and inhalation anaesthesia
C. K. Hofer, A. Zollinger, S. Büchi, R. Klaghofer, D. Serafino, S. Bühlmann, C. Buddeberg, T. Pasch and D. R. Spahn
Br J Anaesth 2003; 91: 631–7

Background: The aim of this study was to assess postoperative patient well-being after total i.v. anaesthesia compared with inhalation anaesthesia by means of validated psychometric tests.
Methods: With ethics committee approval, 305 patients undergoing minor elective gynaecologic or orthopaedic interventions were assigned randomly to total i.v. anaesthesia using propofol or inhalation anaesthesia using sevoflurane. The primary outcome measurement was the actual mental state 90 min and 24 h after anaesthesia assessed by a blinded observer using the Adjective Mood Scale (AMS) and the State-Trait-Anxiety Inventory (STAI). Incidence of postoperative nausea and vomiting (PONV) and postoperative pain level were determined by Visual Analogue Scale (VAS) 90 min and 24 h after anaesthesia (secondary outcome measurements). Patient satisfaction was evaluated using a VAS 24 h after anaesthesia.
Results: The AMS and STAI scores were significantly better 90 min after total i.v. anaesthesia compared with inhalation anaesthesia (P=0.02, P=0.05, respectively), but equal 24 h after both anaesthetic techniques (P=0.90, P=0.78, respectively); patient satisfaction was comparable (P=0.26). Postoperative pain was comparable in both groups 90 min and 24 h after anaesthesia (P=0.11, P=0.12, respectively). The incidence of postoperative nausea was reduced after total i.v. compared with inhalation anaesthesia at 90 min (7 vs 35%, P<0.001), and 24 h (33 vs 52%, P=0.001).
Conclusion: Total i.v. anaesthesia improves early postoperative patient well-being and reduces the incidence of PONV.

Use of the ProSeal^TM laryngeal mask airway in a pregnant patient with a difficult airway during electroconvulsive therapy
N. Ivascu Brown, P. Fogarty Mack, D. M. Mitera and P. Dhar
Br J Anaesth 2003; 91: 752–4

We describe a patient at 20–22 weeks gestation, with a known difficult airway, who underwent eight sessions of electroconvulsive therapy using the ProSeal^TM laryngeal mask airway and controlled ventilation. The airway management options for brief periods of general anaesthesia in patients with increased gastric volume are discussed.

Randomized crossover comparison of the ProSeal^TM laryngeal mask airway with the Laryngeal Tube^® during anaesthesia with controlled ventilation
T. M. Cook, C. McKinstry, R. Hardy and S. Twigg
Br J Anaesth 2003; 91: 678–83

Background: The Laryngeal Tube (LT^®) performs similarly to the classic laryngeal mask airway during controlled ventilation but with an improved airway seal. We compared the laryngeal tube with the ProSeal^TM laryngeal mask airway (PLMA) throughout anaesthesia.
Methods: Thirty-two patients were studied using a randomized cross-over design. The primary outcome measure was airway seal pressure. Secondary outcome measures included peak and plateau airway pressures, time to achieve an airway, ease of insertion, airway manipulations required to achieve a patent airway and grade of fibre-optic laryngoscopy. The proportion of patients in whom good, fair or failed ventilation was achieved was also calculated.
Results: No significant difference was found in regard to seal pressure (PLMA, median 26.5 cm H₂O, range 10–40; LT, median 24, range 6–40; P=0.7, 95% confidence interval of the difference 3.5 to –4.0). There were two failures of insertion or ventilation in the LT group and none in the PLMA group. The peak airway pressure with the PLMA was lower than with the LT but the difference was clinically unimportant (PLMA, mean 16.2 cm H₂O, SD 3.52; LT, mean 17.9, SD 5.21; P=0.02, 95% confidence interval of the difference –3.1 to –0.28). The PLMA took significantly less time to insert than the LT (PLMA, median 18.5 s, interquartile range 14–26; LT, median 22, interquartile range 15–36.5; P<0.02, 95% confidence interval of the difference –21.5 to –1.0). The PLMA gave a significantly better view on fibre-optic laryngoscopy than the LT (P<0.001, 95% confidence interval of the difference in grade –2.0 to –1.0). In the 16 patients in whom the PLMA was used during maintenance of anaesthesia ventilation was good in 15, fair in none and failed in one. The equivalent figures for the LT were good in nine, fair in six and failed in one (P=0.009). There was no significant difference in the plateau airway pressure, ease of insertion of the devices, number of manipulations required to achieve or maintain an airway, or in overall complications.
Conclusion: The two devices performed equally well in terms of seal pressure. The PLMA was quicker to insert. Efficacy of ventilation was significantly better with the PLMA than the LT. The PLMA allowed a significantly better view of the larynx with a fibre-optic laryngoscope, and may therefore be of more use in cases where visualization of the larynx is required.

ANESTHESIOLOGY - TOP

Optimal Dose of Succinylcholine Revisited
Mohamed Naguib, M.B., B.Ch., M.Sc., F.F.A.R.C.S.I., M.D.; Abdulhamid Samarkandi, M.B., B.S., K.S.U.F., F.F.A.R.C.S.I.; Waleed Riad, M.B., B.Ch., M.Sc., A.B., M.D.; Saleh W. Alharby, M.B., B.S., F.R.C.S. (Glas)
Anesthesiology 2003; 99(5):1045-1049

Background: The authors reappraised the conventional wisdom that the intubating dose of succinylcholine must be 1.0 mg/kg and attempted to define the lower range of succinylcholine doses that provide acceptable intubation conditions in 95% of patients within 60 s.
Methods: This prospective, randomized, double-blind study involved 200 patients. Anesthesia was induced with 2 µg/kg fentanyl and 2 mg/kg propofol. After loss of consciousness, patients were randomly allocated to receive 0.3, 0.5, or 1.0 mg/kg succinylcholine or saline (control group). Tracheal intubation was performed 60 s later. A blinded investigator performed all laryngoscopies and also graded intubating conditions.
Results: Intubating conditions were acceptable (excellent plus good grade combined) in 30%, 92%, 94%, and 98% of patients after 0.0, 0.3, 0.5, and 1.0 mg/kg succinylcholine, respectively. The incidence of acceptable intubating conditions was significantly greater (P < 0.05) in patients receiving succinylcholine compared with those in the control group but was not different among the different succinylcholine dose groups. The calculated doses of succinylcholine (and their 95% confidence intervals) that were required to achieve acceptable intubating conditions in 90% and 95% of patients at 60 s were 0.24 (0.19-0.31) mg/kg and 0.56 (0.43-0.73) mg/kg, respectively.
Conclusions: The use of 1.0 mg/kg of succinylcholine may be excessive if the goal is to achieve acceptable intubating conditions within 60 s. Comparable intubating conditions were achieved after 0.3, 0.5, or 1.0 mg/kg succinylcholine. In a rapid-sequence induction, 95% of patients with normal airway anatomy anesthetized with 2 µg/kg fentanyl and 2 mg/kg propofol should have acceptable intubating conditions at 60 s after 0.56 mg/kg succinylcholine. Reducing the dose of succinylcholine should allow a more rapid return of spontaneous respiration and airway reflexes.

The "Intubating Dose" of Succinylcholine: The Effect of Decreasing Doses on Recovery Time
Aaron F. Kopman, M.D.; Bledi Zhaku, B.A.; Kane S. Lai, M.D.
Anesthesiology 2003; 99(5):1050-1054

Background: The usually cited "intubation dose" of succinylcholine is 1.0 mg/kg. In the majority of patients, this dose will produce apnea of sufficient duration that significant hemoglobin desaturation may occur before neuromuscular recovery takes place in those whose ventilation is not assisted. This study was undertaken to examine the extent to which reducing this dose would decrease the duration of action of succinylcholine.
Methods: During stable desflurane/oxygen/opioid anesthesia and after adequate twitch stabilization, neuromuscular function was recorded with an acceleromyographic monitor. Supramaximal stimuli were delivered at 0.10 Hz. Patients received 0.40, 0.60, or 1.0 mg/kg succinylcholine, and twitch height was monitored for at least 20 min thereafter.
Results: The onset times to maximal effect were 105 ± 23 s, 81 ± 19 s, and 71 ± 22 s, respectively. The lowest dose (0.40 mg/kg) did not reliably produce 100% twitch depression. The times to 90% twitch recovery at the adductor pollicis in the three groups were 6.6 ± 1.5 min, 7.6 ± 1.6 min, and 9.3 ± 1.2 min, respectively.
Conclusions: Reducing the dose of succinylcholine from 1.0 mg/kg to 0.60 mg/kg shortens the duration of effect at the adductor pollicis by more than 90 s. The authors believe that even this modest decrease in the duration of drug-induced paralysis is often worth pursuing.

Comparison of the LMA-Classic™ with the New Disposable Soft Seal Laryngeal Mask in Spontaneously Breathing Adult Patients
André A. J. van Zundert, M.D., Ph.D.; Kristine Fonck, M.D.; Baha Al-Shaikh, F.F.A.R.S.C.I.; Eric Mortier, M.D., Ph.D.
Anesthesiology 2003; 99(5):1066-1071

Background: The laryngeal mask airway LMA-Classic™ has been used widely in clinical practice. A new disposable supraglottic airway device, the Soft Seal LM, has been introduced recently. In a randomized study, the authors compared the LMA-Classic™ and the disposable Soft Seal LM in terms of their clinical performance, cuff pressures during nitrous oxide anesthesia, position of the laryngeal mask in situ by fiberoptic evaluation, and morbidity in a wide range of routine general surgery procedures.
Methods: A total of 200 adult patients were randomly assigned to a size 4 laryngeal mask in two equal-sized groups for airway management during surgery: (1) LMA-Classic™ (Intavent Orthofix Ltd., Maidenhead, Berkshire, United Kingdom); or (2) Soft Seal LM (Portex Ltd., Hythe, Kent, United Kingdom). Anesthesia was administered with fentanyl, propofol, nitrous oxide, oxygen, and sevoflurane. The variables studied were ease of insertion, fiberoptic view, time in situ, incidence of blood on the laryngeal mask at the time of removal, and the incidence of postoperative sore throat at 2 and 24 h. The laryngeal mask cuff pressures were measured continuously. Intracuff pressure limitation was not attempted.
Results: The LMA-Classic™ and the Soft Seal LM showed similar clinical performances, as shown by their insertion time (successful insertion at first attempt was achieved within 20 s in 97% with LMA-Classic™ vs. 95% with Soft Seal LM), fiberoptic evaluation of the anatomic position of the laryngeal mask, and satisfactory anesthesia conditions. Laryngeal mask cuff pressures increased from 45 to 100.3 mmHg in the LMA-Classic™ and from 45 to 46.8 mmHg in the Soft Seal LM (P< 0.001). Macroscopic blood was seen on only four occasions in the LMA-Classic™ group. The incidence of sore throat was significantly increased at 2 h postoperatively when using the LMA-Classic™, although there was no difference at 24 h after surgery.
Conclusions: In spontaneously breathing adult patients requiring a size 4 laryngeal mask airway, the new disposable Soft Seal LM device is an acceptable alternative to the reusable LMA-Classic™, resulting in a good laryngeal seal and offering similar clinical performance. Cuff pressures increase substantially when the LMA-Classic™ is used but not when using the Soft Seal LM. There was less trauma to patients using the Soft Seal LM, as assessed by the incidence of sore throat in the early postoperative period.

Neuropathy following Axillary Brachial Plexus Block: Is It the Tourniquet?
(Case Report)
Christopher J. Jankowski, M.D.; Mark T. Keegan, M.B., M.R.C.P.I.; Charles F. Bolton, M.D.; Barry A. Harrison, M.B.B.S., F.A.N.Z.C.A., F.R.A.C.P.
Anesthesiology 2003; 99(5):1230-2

No abstract available.

Cyclooxygenase-2 Inhibitors in Postoperative Pain Management: Current Evidence and Future Directions (REVIEW ARTICLE)
Ian Gilron, M.D., M.Sc., F.R.C.P.C.; Brian Milne, M.D., M.Sc., F.R.C.P.C.; Murray Hong, Ph.D.
Anesthesiology 2003; 99(5): 1198-120

Published postoperative trials of cyclooxygenase-2 inhibitors suggest a therapeutic profile comparable to nonselective nonsteroidal antiinflammatory drugs. Future comparative trials powered to evaluate adverse outcomes such as bleeding, gastrointestinal ulceration, and cardiovascular events are needed to demonstrate whether cyclooxygenase-2 inhibitors offer any benefit over nonselective nonsteroidal antiinflammatory drugs.

PUB MED - TOP

Factitious oxygen desaturation after isosulfan blue injection
Heinle E, Burdumy T, Recabaren J.
Am Surg. 2003 Oct;69(10):899-901

Profound pulse oximetery desaturations are observed following isosulfan blue dye injection during breast sentinel node biopsy. The objective of this study was to examine the effect isosulfan dye has on oxygenation status and the reliability of pulse oximetery in evaluating this parameter. After study design, institutional review board approval was obtained. A prospective 5-month study was performed between January and April 2002. Twenty-one women with invasive breast cancer were monitored during breast sentinel node biopsies. Twenty-two operative cases were analyzed by pulse oximetry and arterial catheterization to record oxygen saturation. Time intervals of analysis were 0, 5, 10, 20, 30, and 40 minutes following injection of isosulfan blue dye. Simultaneous pulse oximetry and arterial blood gas analysis allowed comparison of indirect oximetry oxygen saturation (SpO₂) to actual arterial oxygen saturation (SaO₂). SpO₂ values were decreased from baseline values at 10, 20, and 30 minutes without decrease in SaO₂ saturation (P < 0.001). The mean oximetry SpO₂ desaturation was 5.6 per cent, with a range to 9 per cent. After injection with isosulfan blue dye, a significant SpO₂ desaturation occurs. Clinicians must be aware of the factitious effect isosulfan blue dye has on SpO₂ monitoring, to assess accurately the oxygenation status of the anesthetized patient.

Intraperitoneal application of bupivacaine plus morphine for pain relief after laparoscopic cholecystectomy
J. Hernández-Palazón, J. A. Tortosa, V. Nuño de la Rosa, J. Giménez-Viudes, G. Ramírez, R. Robles
European Journal of Anaesthesiology Volume 20 Number 11, pp 891-6

Background and objective: Intraperitoneal administration of a local anaesthetic in combination with an opioid, for the relief of postoperative pain, has already been reported except after laparoscopic cholecystectomy. This study was aimed at assessing the analgesic effect of the intraperitoneal administration of bupivacaine and morphine in patients undergoing laparoscopic cholecystectomy.
Methods: At the end of laparoscopic cholecystectomy, in a double-blind, randomized manner, one of the following injections was given intraperitoneally. There were 30 patients in each group: Group 1, physiological saline 30 mL; Group 2, bupivacaine 0.25% 30 mL; Group 3, bupivacaine 0.25% 30 mL plus morphine 2 mg. In addition, Group 2 received 2 mg intravenous (i.v.) morphine in 2 mL saline, and Groups 1 and 3, 2 mL saline intravenously. Patients’ postoperative pain was evaluated using a visual analogue scale and a verbal rating score. The postoperative analgesic requirement was assessed by the total dose of metamizol administered by an i.v. patient-controlled analgesia (PCA) device. Pain, vital signs, supplemental analgesic consumption and side-effects were recorded for all patients for 24 h.
Results: There were no differences between the three groups regarding pain scores (at rest and coughing) during the study except in the first 2 h, when scores were lower for patients receiving intraperitoneal bupivacaine plus i.v. morphine (P < 0.05). Supplemental consumption of metamizol was significantly lower (P < 0.05) in Group 3 than in Group 1 during the first 6 h after surgery. However, the cumulative doses of metamizol were also lower in Group 2 than in Groups 1 and 3 over the entire study (2025 ± 1044 mg vs. 4925 ± 1238 and 4125 ± 1276 mg; P < 0.05).
Conclusions: In patients undergoing laparoscopic cholecystectomy, the intraperitoneal administration of morphine plus bupivacaine 0.25% reduced the analgesic requirements during the first 6 postoperative hours compared with the control group. However, the combination of intraperitoneal bupivacaine 0.25% and i.v. morphine was more effective for treatment of pain after laparoscopic cholecystectomy.

Efficacy of tramadol versus meperidine for pain relief and safe recovery after adenotonsillectomy
Z. Özer, K. Görür, A. A. Altunkan, E. Bilgin, H. Çamdeviren, U. Oral
European Journal of Anaesthesiology Volume 20 Number 11, pp 920-4

Background and objective: Adequate relief of pain after tonsillectomy is a common problem. We compared meperidine and tramadol when given at induction of anaesthesia with respect to their effects on postoperative pain relief and emergence characteristics after adenotonsillectomy in children.
Methods: Fifty children aged 4–7 yr undergoing tonsillectomy were randomly assigned to receive either tramadol 1 mg kg^-1 (n = 25) or meperidine 1 mg kg^-1 (n = 25) before commencement of the surgical procedure. Anaesthesia was induced with propofol (with cis-atracurium for muscle relaxation) and maintained with sevoflurane in oxygen and nitrous oxide. Postoperative pain was scored by a blinded observer using a facial pain scale in the recovery room at 0 (at arrival of the patient in the postoperative care unit) and at 10, 20 and 45 min thereafter. Agitation scores were also assessed by the same observer at 0 min. Heart rate and mean arterial pressure were recorded at regular intervals. The time to recovery to spontaneous respiration and the incidence of postoperative nausea and vomiting were noted.
Results: Facial pain scale scores were increased in the tramadol group at 0, 10 and 20 min (P < 0.05). No difference was observed in scores at the 45th min postoperation. Agitation scores were higher in the tramadol group than in the meperidine group. No statistical difference was found between the two groups. Heart rates and mean arterial pressures were similar in both groups. The time to recovery to spontaneous respiration was delayed with meperidine compared with tramadol (P < 0.05). The incidence of nausea and vomiting was not statistically different between groups.
Conclusions: Meperidine was more effective for pain relief and provides better emergence characteristics than tramadol after tonsillectomy in children.

Is skin disinfection with 10% povidone iodine sufficient to prevent epidural needle and catheter contamination?
Yentur EA, Luleci N, Topcu I, Degerli K, Surucuoglu S.
Reg Anesth Pain Med. 2003 Sep-Oct;28(5):389-93

BACKGROUND AND OBJECTIVES: Epidural space infection is a potential complication of epidural catheter placement. In this study, we investigated the incidence of epidural needle and catheter contamination after skin surface disinfection with 10% povidone-iodine (PI).
METHODS: Sixty seven patients having surgery under epidural anesthesia were enrolled in this prospective study. After preparation with 10% PI, skin swab cultures were taken from the site of catheter insertion. Epidural needles were cultured immediately after epidural catheters were placed. Catheters were removed at 48 hours and 2 to 3 cm of the distal tips were cultured as well.
RESULTS: Fifty-six skin swabs, 52 epidural needles, and 48 catheters were cultured. Although only 3.5% (2) colonization was observed on skin surface cultures, 34.6% (18) of the epidural needles and 45.8% (22) of the catheters were colonized. No systemic or local infection was observed.
CONCLUSIONS: Our results suggest that despite skin surface disinfection with PI, there is still significant risk for contamination of needles and catheters during epidural catheterization.

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