Prolongation of QTc Interval after Postoperative Nausea and Vomiting Treatment by Droperidol or Ondansetron.
Charbit, Beny M.D. ; Albaladejo, Pierre M.D., Ph.D. ; Funck-Brentano, Christian M.D., Ph.D. ; Legrand, Mathieu M.D.; Samain, Emmanuel M.D., Ph.D. ; Marty, Jean M.D., Ph.D.
Anesthesiology. 102(6):1094-1100, June 2005.

Background: At dosages above 0.1 mg/kg, droperidol inducesa dose-dependent QTc interval prolongation. Although subject to controversy, low-dose droperidol has recently been suspected to induce cardiac arrhythmias. Hence, 5-hydroxytryptamine type 3 antagonists have become the first-line drug for management of postoperative nausea and vomiting. These drugs are also known to prolong the QTc interval at high dosages. This study describes QTc interval changes associated with postoperative nausea and vomiting treatment by droperidol or ondansetron at low doses.
Methods: Eighty-five patients with postoperative nausea and vomiting were included in this prospective, single-blind study. Patients received either 0.75 mg intravenous droperidol (n = 43) or 4 mg intravenous ondansetron (n = 42). Electrocardiographic recordings were obtained before administration of antiemetic drug and then 1, 2, 3, 5, 10, and 15 min after. Electrocardiographic monitoring was maintained for 3 h in eight patients in each group.
Results: The QTc interval was prolonged (> 450 ms in men, > 470 ms in women) in 21% of the patients before antiemetic drug administration. This was significantly correlated with lower body temperature and longer duration of anesthesia. Compared with predrug QTc measurement, both antiemetics were associated with a significant QTc interval prolongation (P < 0.0001). The mean maximal QTc interval prolongation was 17 +/- 9 ms after droperidol occurring at the second minute and 20 +/- 13 ms after ondansetron at the third minute (both P < 0.0001). Compared with predrug measurement, the QTc interval was significantly lower after the 90th minute in both groups.
Conclusions: Droperidol and ondansetron induced similar clinically relevant QTc interval prolongations. When used in treatment of postoperative nausea and vomiting, a situation where prolongation of the QTc interval seems to occur, the safety of 5-hydroxytryptamine type 3 antagonists may not be superior to that of low-dose droperidol.

Effect of Low-dose Droperidol on the QT Interval during and after General Anesthesia: A Placebo-controlled Study.
White, Paul F. Ph.D., M.D.; Song, Dajun M.D., Ph.D. ; Abrao, Joao M.D., Ph.D. ; Klein, Kevin W. M.D. ; Navarette, Bryan M.S. 
Anesthesiology. 102(6):1101-1105, June 2005.

Abstract:
Background: Since the effects of antiemetic doses of droperidol on the QT interval have not been previously studied, the authors designed a randomized, double-blind, placebo-controlled study to evaluate the intraoperative and postoperative effects of small-dose droperidol (0.625 and 1.25 mg intravenous) on the QT interval when used for antiemetic prophylaxis during general anesthesia.
Methods: One hundred twenty outpatients undergoing otolaryngologic procedures with a standardized general anesthetic technique were enrolled in this study. After anesthetic induction and before the surgical incision, 60 patients were given either saline or 0.625 or 1.25 mg intravenous droperidol in a total volume of 2 ml. A standard electrocardiographic lead II was recorded immediately before and every minute after the injection of the study medication during a 10-min observation period. The QTc (QT interval corrected for heart rate) was evaluated from the recorded electrocardiographic strips. In 60 additional patients, a 12-lead electrocardiogram was obtained before and at specific intervals up to 2 h after surgery to assess the effects of droperidol and general anesthesia on the QTc. Any abnormal heartbeats or arrhythmias during the operation or the subsequent 2-h monitoring interval were also noted.
Results: Intravenous droperidol, 0.625 and 1.25 mg, prolonged the QT interval by an average of 15 +/- 40 and 22 +/- 41 ms, respectively, at 3-6 min after administration during general anesthesia, but these changes did not differ significantly from that seen with saline (12 +/- 35 ms) (all values mean +/- SD). There were no statistically significant differences among the three study groups in the number of patients with greater than 10% prolongation in QTc (vs. baseline). Although general anesthesia was associated with a 14- to 16-ms prolongation of the QTc interval in the early postoperative period, there was no evidence of droperidol-induced QTc prolongation after surgery. Finally, there were no ectopic heartbeats observed on any of the electrocardiographic rhythm strips or 12-lead recordings during the perioperative period.
Conclusion: Use of a small dose of droperidol (0.625-1.25 mg intravenous) for antiemetic prophylaxis during general anesthesia was not associated with a statistically significant increase in the QTc interval compared with saline. More importantly, there was no evidence of any droperidol-induced QTc prolongation immediately after surgery.

Intubating Laryngeal Mask Airway in Morbidly Obese and Lean Patients: A Comparative Study.
Combes, Xavier M.D. ; Sauvat, Stephane M.D. ; Leroux, Bertrand M.D. ; Dumerat, Marc M.D.; Sherrer, Emanuel M.D. ; Motamed, Cyrus M.D. ; Brain, Archie M.D. ; D'Honneur, Gilles M.D. 
Anesthesiology. 102(6):1106-1109, June 2005.

Background: The intubating laryngeal mask airway (ILMA) was designed using the characteristics of healthy-weight subjects but was shown to be an effective airway device in morbidly obese patients. The authors compared airway management quality in morbidly obese and lean patients with use of the ILMA.
Methods: Fifty morbidly obese and 50 lean patients (mean body mass indexes, 42 and 27 kg/m2, respectively) were enrolled in this prospective study. After induction of general anesthesia, characteristics of airway management were judged on safety and efficiency parameters, including success rate at ventilation and intubation and airway management quality criteria, such as the number of patients who required adjustment maneuvers, the number of failed tracheal intubation attempts, the total duration of airway management, and an overall difficulty visual analog scale score.
Results: The ILMA was successfully inserted and adequate ventilation through the ILMA was achieved in all 100 patients. The success rates of tracheal intubation through the ILMA were similar in obese and lean patients (96% and 94%, respectively). The numbers of failed blind tracheal access attempts and patients who required airway-adjustment maneuvers were significantly reduced in obese patients as compared with lean patients. Four obese patients experienced transient episodes of oxygen desaturation (oxygen saturation < 90%) before adequate bag ventilation was established with the ILMA.
Conclusion: The authors confirmed that the ILMA was an efficient airway device for airway management of both lean and obese patients. In the conditions of this study, the authors observed that airway management with the ILMA was simpler in obese patients as compared with lean patients.

Development and Validation of a Perioperative Satisfaction Questionnaire.
Auquier, Pascal M.D., Ph.D. ; Pernoud, Nicolas M.D. ; Bruder, Nicolas M.D. ; Simeoni, Marie-Claude M.D., Ph.D. ; Auffray, Jean-Pierre M.D.; Colavolpe, Christian M.D. ; Francois, Georges M.D.; Gouin, Francois M.D. ; Manelli, Jean-Claude M.D. ; Martin, Claude M.D.; Sapin, Christophe M.Sc.; Blache, Jean-Louis M.D.
Anesthesiology. 102(6):1116-1123, June 2005.

Background: Satisfaction is considered a valuable measure of outcome of healthcare processes. Only a few anesthesia-related validated questionnaires are reported. Because their scope is restricted to specific clinical contexts, their use remains limited. The objective of the current study was to develop and validate a self-reported questionnaire, Evaluation du Vecu de l'Anesthesie Generale (EVAN-G), assessing the satisfaction of the perioperative period surrounding general anesthesia.
Methods: Development of the EVAN-G questionnaire comprised a phase of item generation and a phase of psychometric validation. The patient sample was generated to be proportionally matched to the population of patients undergoing general anesthesia in France. The structure of the questionnaire was identified studying interitem, item-dimension, and interdimension correlations and factor analyses. Data were concurrently gathered to assess external validity. The discriminant validity was determined by comparison of scores across well known patient groups. Reliability was assessed by computation of Cronbach [alpha] coefficients and by test-retest.
Results: Eight hundred seventy-four patients were recruited in eight anesthesia departments. The EVAN-G includes 26 items; six specific scores and one global index score are available. Correlations between EVAN-G scores and other concurrent measures supported convergent validity. The EVAN-G correlated poorly with age, American Society of Anesthesiologists physical status, total anesthesia time, and number of previous anesthesias. Significantly higher satisfaction was reported by patients older than 65 yr, belonging to the laryngeal mask group. Reliability and reproducibility were shown.
Conclusion: The EVAN-G adds important information oriented toward patients' perceptions. The authors' approach provides a novel, valid, and reliable tool that may be used in anesthesia practice.

ACTA ANAESTHESIOLOGICA SCANDINAVICA - TOP

Emotional and interpersonal factors are most important for patient satisfaction with anaesthesia
M. Capuzzo , F. Landi, A. Bassani, L. Grassi, C. A. Volta and R. Alvisi.
Acta Anaesthesiologica Scandinavica Volume 49 Issue 6 Page 759 - July 2005

Background: Questionnaires to evaluate patient satisfaction with anaesthesia mainly consider physiological aspects. This study was performed to identify the items of value for patients having anaesthesia (pilot phase) and to validate the questionnaire built on these findings in a new group of inpatients.
Methods: In the pilot phase, 100 surgical patients were interviewed and asked whether each of the 23 items selected by a panel of providers was relevant (score 1) and to rank these from 1 (additional score 6) to 5 (additional score 2). The resulting 10-item final instrument was administered to 219 consecutive inpatients by interview, after recent anaesthesia, asking them how much of each item they received (item received) and the level of satisfaction with the same item, using Numerical Rating Scales (range 0 alt=- align=bottom>10).
Results: In the pilot phase, gender, age, education and surgery did not influence the score enough to change the first 10 rank-ordered items. The 219 patients subsequently studied did not differ from those missing the questionnaire administration. The patients aged less than 55 years showed lower satisfaction scores than those aged 55 years or more (P = 0.019). In all items, except 'feeling anxious/frightened', the item received was significantly associated with the satisfaction reported. 'Kindness/regard of caregivers' together with 'information given by anaesthetist' and 'feeling safe' predicted 47% of the variance in total patient satisfaction.
Conclusions: Inpatients value highly those elements of care that pertain to emotional and interpersonal relationships.

Relationship between arterial and end-tidal carbon dioxide pressures during anesthesia using a laryngeal tube
J. S. Lee, S. B. Nam, C. H. Chang, D. W. Han, Y. W. Lee and C. S. Shin
Acta Anaesthesiologica Scandinavica Volume 49 Issue 6 Page 759 - July 2005

Background: The Laryngeal Tube® (LT), (VBM Medizintechnik, Sulz, Germany) is a relatively new supraglottic device for controlling the airway. Arterial carbon dioxide tension (PaCO2) can be estimated by monitoring the end-tidal tension of carbon dioxide (PETCO2). The relationship between PETCO2 and PaCO2 during controlled ventilation via the LT has not been reported.
Methods: During general anesthesia, 45 patients were mechanically ventilated using an LT. PETCO2 and PaCO2 were measured once PETCO2 had reached a steady state. The LT was then removed and the trachea intubated using an endotracheal tube (ETT), and the identical ventilatory variables were resumed. Following stabilization, PETCO2 was again determined and PaCO2 estimated.
Results: The mean PETCO2 and PaCO2 values were 4.43 ± 0.26 kPa and 4.67 ± 0.32 kPa, respectively, during LT ventilation, and 4.36 ± 0.23 kPa and 4.61 ± 0.26 kPa, respectively, during ETT ventilation. Analysis of differences between the PETCO2 and PaCO2 values using the Bland and Altman method revealed a bias ± precision of 0.24 ± 0.15 kPa for LT and 0.27 ± 0.15 kPa for ETT. The root mean square error was 0.28 for the LT and 0.30 for the ETT.
Conclusion: This study suggests that for healthy adult patients mechanically ventilated via the LT, the PETCO2 value reflects the PaCO2 value as closely as when patients are ETT ventilated, allowing capnometry to be used to evaluate the adequacy of ventilation.

BRITISH JOURNAL OF ANAESTHESIA - TOP

Chronic postoperative pain: the case of inguinal herniorrhaphy
E. Aasvang and H. Kehlet

Extract: That surgical injury can lead to chronic pain is now well established. From these reviews and studies using a systematic collection of data, the estimated incidences of chronic pain after various procedures are: leg amputation about 60%, thoracotomy about 50%, breast surgery about 30%, cholecystectomy 10–20%, and inguinal herniorrhaphy about 10%. Predictive risk factors for chronic postoperative pain are: preoperative pain, repeat surgery, psychological vulnerability, workers compensation, a surgical approach with risk of nerve damage, moderate or severe intensity of acute postoperative pain, radiation therapy, neurotoxic chemotherapy, depression, neuroticism, and anxiety.

Recent advances in the non-pharmacological management of postoperative nausea and vomiting
D. J. Rowbotham
British Journal of Anaesthesia 2005 95(1):77-81

Extract: Acupuncture is available worldwide for the treatment of many conditions and complaints. In recent years, clinical and laboratory investigations have been conducted in an attempt to provide an evidence-base in support of this technique. Although in some cases the quality of the data is poor, systematic reviews have been published describing the use of acupuncture in chronic pain (e.g. back, neck, arthritis, headache, fibromyalgia), weight reduction, addiction, temporomandibular joint disorders, asthma, smoking cessation, emesis, stroke, and tinnitus. The nature, quality, and implications of the data are often fiercely debated. However, it is generally accepted that there is clear evidence that acupuncture can be effective for nausea and vomiting associated with pregnancy, chemotherapy, and the postoperative period.

Ketorolac analgesia for inguinal hernia repair is not improved by peripheral administration
Kenneth J. Kardash, MD, Jacob Garzon, MD, Ana M. Velly, DDS PhD and Michael J. Tessler, MD
Canadian Journal of Anesthesia 52:613-617 (2005)

Purpose: It has been suggested that ketorolac, a non-steroidal anti-inflammatory drug (NSAID) available for parenteral use, may result in prolonged (24 hr) postoperative analgesia through a peripheral mechanism when added to local anesthetic infiltration. Our objective was to assess this effect by controlling for systemic absorption of the drug.
Methods: This randomized, double-blind trial studied 40 men undergoing elective inguinal hernia repair under spinal anesthesia. All patients received 19 mL of lidocaine 1% infiltrated in the operative field before incision. Patients were randomized into two groups of 20. The surgical site group received ketorolac 30 mg added to the lidocaine infiltration. In the control group, ketorolac 30 mg was injected subcutaneously in the contralateral abdominal wall. Numeric rating scores (0–10) of pain at rest and with movement were recorded at the time of discharge from the recovery room and at 24 hr postoperatively. Time to first analgesia, postoperative iv morphine use, total time in the recovery room, and total oral analgesic use in the first 24 hr were also compared.
Results: There were no significant differences between groups with respect to any of the measured variables. In both groups, pain scores were low at rest (1.9 ± 1.4 vs 2.2 ± 1.8, surgical site and systemic groups, respectively) and moderate with movement (5.3 ± 2.2, 5.0 ± 1.8) after anesthetic recovery. Pain scores were similar at 24 hr (1.1 ± 1.3, 1.9 ± 1.6 at rest; 5.7 ± 2.0, 6.2 ± 2.2 with movement).
Conclusion: Adding ketorolac to lidocaine infiltration for hernia repair does not improve or prolong postoperative analgesia compared to systemic administration.

Apnea during induction of anesthesia with sevoflurane is related to its mode of administration
Carlo Pancaro, MD, Simone Giovannoni, MD, Adelchi Toscano, MD and Vito Aldo Peduto, MD
Canadian Journal of Anesthesia 52:591-594 (2005)

Purpose: The incidence and duration of apnea during sevoflurane anesthesia have not been fully characterized. We hypothesized that sevoflurane at slowly increasing concentrations reduces incidence and shortens the duration of apnea compared to administration of a highly concentrated anesthetic mixture.
Methods: 131 women were randomly assigned to receive 35% oxygen in air and sevoflurane at: incremental concentrations of 1%, from 1% to 8% (group 1–8%, n = 42); decremental-incremental concentrations of 2%, from 8% to 4% and then from 4% to 8% (group 8–4–8%, n = 36); or fixed concentrations of 8% for induction of anesthesia (group 8%, n = 53). A blinded investigator observed whether and for how long patients stopped breathing.
Results: All groups reached 2.5 minimum alveolar concentration of end-tidal sevoflurane. Although apnea was observed in all groups, it was more frequent in the 8% group than in 1 to 8% (68% vs 21%, P < 0.05) or 8 to 4 to 8% groups (68% vs 20%, P < 0.05). Duration of apnea was also more pronounced in the 8% group than in 1 to 8% and 8 to 4 to 8% groups ( 58 ± 25 s vs 32 ± 18 sec, P < 0.05 and vs 35 ± 16 sec, P < 0.05, respectively).
Conclusions: Sevoflurane induces apnea more frequently and for longer duration at a fixed high concentration compared to incremental or decremental-incremental concentrations. Decremental-incremental concentrations offer the additional advantage of a speed of induction similar to that elicited by the 8% concentration.

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Hemodynamics and oxygen saturation during intravenous sedation for office-based laser-assisted uvuloplasty
Cillo JE, Finn R.
J Oral Maxillofac Surg. 2005 Jun;63(6):752-5

PURPOSE: Patients undergoing office-based laser-assisted uvuloplasty (LAUP) for snoring or mild obstructive sleep apnea are generally obese and have a high Mallampati score. Because avoidance of supplemental oxygen during laser procedures is generally mandated, the potential for intraoperative desaturation is high. This study was designed to look at intraoperative hemodynamic changes, respiration patterns, and oxygen saturations during intravenous sedation with midazolam and fentanyl during LAUP procedures.
MATERIALS AND METHODS: This was a retrospective anesthesia chart review of 15 consecutive patients undergoing midazolam/fentanyl intravenous sedation for office-based LAUP treatment for snoring and/or mild obstructive sleep apnea. Data recorded were noninvasive baseline and intraoperative hemodynamic measurements at 5-minute intervals for systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP), pulse (P), and rate-pressure product (RPP). Data collected were reported as mean values with standard deviation. Statistical analysis using the Student's t test was performed and found significant for P<.05.
RESULTS: All changes from baseline were statistically insignificant, SBP (P=.4), DBP (P=.2), MAP (P=.2), P (P=.1), PP (P=.9), RPP (P=.5), RR (P=.9), and SpO2 (P=.4), and all within +/-20% of baseline (range, -5.0% to +7.5%).
CONCLUSION: Midazolam and fentanyl intravenous sedation with local anesthesia maintained intraoperative hemodynamic and oxygenation variables close to baseline for office-based LAUP procedures.