Shun-Ming Chan

Effect on postoperative sore throat of spraying the endotracheal tube cuff with benzydamine hydrochloride, 10% lidocaine, and 2% lidocaine.

BACKGROUND:Postoperative sore throat (POST) is a common complication after endotracheal intubation. We compared the effectiveness on POST of spraying the endotracheal tube (ETT) cuff with benzydamine hydrochloride, 10% lidocaine, and 2% lidocaine. METHODS:Three hundred seventy-two patients were randomly allocated into 4 groups. The ETT cuffs in each group were sprayed with benzydamine hydrochloride, 10% lidocaine hydrochloride, 2% lidocaine hydrochloride, or normal saline before endotracheal intubation. After insertion, the cuffs were inflated to an airway leak pressure of 20 cm H2O. Anesthesia was maintained with propofol. The patients were examined for sore throat (none, mild, moderate, or severe) at 1, 6, 12, and 24 hours after extubation. RESULTS:The highest incidence of POST occurred at 6 hours after extubation in all groups. There was a significantly lower incidence of POST in the benzydamine group than 10% lidocaine, 2% lidocaine, and normal saline groups (P < 0.05) at each observation time point. At 6 hours after extubation, the incidence of POST was significantly lower in the benzydamine group (17.0%) compared with 10% lidocaine (53.7%), 2% lidocaine (37.0%), and normal saline (40.8%) groups (P < 0.05). The benzydamine group had significantly decreased severity of POST compared with the 10% lidocaine, 2% lidocaine, and normal saline groups (P < 0.05) at each observation time point. Compared with the 2% lidocaine and normal saline groups, the 10% lidocaine group had significantly increased severity of POST at 1, 6, and 12 hours after extubation. There were no significant differences among groups in local or systemic side effects. CONCLUSIONS:Spraying benzydamine hydrochloride on the ETT cuff is a simple and effective method to reduce the incidence and severity of POST.

Composite auditory evoked potential index versus bispectral index to estimate the level of sedation in paralyzed critically ill patients: a prospective observational study.

BACKGROUND: Electromyographic activity (EMG) has been reported to elevate the Bispectral Index (BIS) in patients not receiving neuromuscular blockade while under sedation in the intensive care unit (ICU). We investigated the change of the composite A-line autoregressive index (AAI) and BIS after administration of muscle relaxants in sedated surgical ICU patients. METHODS: We prospectively investigated 38 patients who required administration of a muscle relaxant while continuously sedated with midazolam hydrochloride and fentanyl citrate to achieve a Ramsay Sedation Scale value equal to 5. BIS, EMG activity of BIS (EMG-BIS), signal quality index of BIS, AAI, EMG activity of AAI (EMG-AAI), and acceleromyography at the adductor pollicis muscle were recorded simultaneously every 5 min for 30 min before and after neuromuscular blockade. Students t-test, the Wilcoxon′s signed ranks test, and the Spearman test were calculated using the standard statistics software SPSS 10.0 (SPSS Inc., Chicago, IL). RESULTS: After administration of a muscle relaxant, BIS (58.61 ± 7.45 vs 44.68 ± 6.65, P < 0.001), EMG-BIS (37.33 ± 7.15 vs 27.24 ± 1.51, P < 0.001), AAI (34.11 ± 10.96 vs 15.97 ± 6.69, P < 0.001), and EMG-AAI (59.58 ± 9.57 vs 1.00 ± 0.00, P < 0.001) decreased significantly. Significant correlations between BIS and EMG-BIS (rs = 0.75, P < 0.001) and AAI and EMG-AAI (rs = 0.87, P < 0.001) were also found during the baseline period. CONCLUSIONS: This study demonstrated that, in sedated ICU patients, BIS and AAI markedly decreased after administration of myorelaxant, and the decreased BIS and AAI values after neuromuscular blockade were correlated to those usually seen in the state of surgical anesthesia, respectively.

Determining an Optimal Tracheal Tube Cuff Pressure by the Feel of the Pilot Balloon: A Training Course for Trainees Providing Airway Care

BACKGROUND High cuff pressure of tracheal tube (TT) may cause tracheal damage. Maintaining an optimal cuff pressure is important in tracheal intubation. This study aimed to examine whether inexperienced anesthetists or airway care providers, after training and practice, demonstrate more expertise in the determination of optimal cuff pressure by feeling the pilot balloon with their fingers. METHODS One hundred participants were asked to inflate the TT cuff with an air volume that they believe to be correct based on their previous experience. The cuff pressure after inflation was measured by a manometer. Then, the cuff of a standard adult TT was inflated with air until the pressure reached 25 cmH2O, and each participant was instructed to palpate the pilot balloon to feel the pressure, until s/he became accustomed to the feeling. After training, the same procedure was performed immediately, and repeated 1 week and 1 month later. We compared the pre-training data with the post-training data, and the differences between seniority of employment and age. RESULTS A total of 98 examinees completed the study. Before training, the mean cuff pressure they determined to be correct was actually 29.3 +/- 19.49 cmH2O; 32.7% of the examinees had over-inflated the cuff. The cuff pressures they inflated immediately, 1 week and 1 month after training were significantly different from those found before training (p = 0.009, p = 0.038 and p = 0.045, respectively). Before training, the performance of the participants who were of middle seniority (5-10 years of experience) and middle age (30-45 years old) was significantly better than that of the less experienced (< 5 years of experience; p = 0.007) and younger participants (< 30 years old; p = 0.002). CONCLUSION The anesthesia trainers in this study are capable of teaching TT cuff inflation correctly. After practical training, the airway care providers, irrespective of seniority or age, can roughly determine an optimal TT cuff pressure non-instrumentally.

Comparison between intraoperative fentanyl and tramadol to improve quality of emergence.

Background: Cough causes poor quality of emergence from anesthesia and risks of several complications. We compared fentanyl and an antitussive action of tramadol on the quality of emergence and postoperative outcome. Methods: A total of 110 adults (18 to 83 y) of American Society of Anesthesiologists physical status I–III undergoing elective lumbar microdiscectomy with intubated total intravenous anesthesia were randomly divided into 2 groups of 55 each. The patients assigned to the fentanyl group received a dose of 1 &mgr;g/kg of fentanyl, whereas those assigned to the tramadol group received 1 mg/kg of tramadol, at the beginning of skin closure. We recorded the incidence of cough, quality of extubation at fixed times, maximal heart rates, maximal blood pressure during emergence, postoperative pain scores, and consumption of fentanyl. In addition, postoperative sore throat (POST), hoarseness, postoperative nausea and vomiting, and other anesthetic and surgical-related complications were recorded. Results: Tramadol reduced cough incidence, improved extubation quality, and provided more stable hemodynamics during emergence. There was no significant difference in postoperative pain, fentanyl consumption, incidence and severity of POST, hoarseness, and postoperative nausea and vomiting between groups. Moreover, we found that the incidence of POST did not correlate with cough incidence. Conclusions: A dose of 1 mg/kg of tramadol administered intravenously 30 minutes before the expected extubation, compared with 1 &mgr;g/kg of fentanyl, decreased cough incidence, improved emergence quality, and provided stable hemodynamics. However, there was no significant difference between tramadol and fentanyl in pain scores and fentanyl consumption postoperatively.

Confounding Factors to Predict the Awakening Effect-Site Concentration of Propofol in Target-Controlled Infusion Based on Propofol and Fentanyl Anesthesia

We conducted a large retrospective study to investigate the confounding factors that predict Ce ROC under propofol-based TIVA with TCI. We recorded sex, age, height, weight, Ce LOC, Ce ROC, total propofol and fentanyl consumption dose, and anesthetic time. Simple linear regression models were used to identify potential predictors of Ce ROC, and multiple linear regression models were used to identify the confounding predictors of Ce ROC. We found that Ce ROC correlated with age, sex, Ce LOC, and both total fentanyl and propofol consumption dose. The prediction formula was: Ce ROC = 0.87 - 0.06 × age + 0.18 × Ce LOC + 0.04 (if fentanyl consumption > 150 μg; if not, ignore this value) + 0.07 × (1 or 2, according to the total propofol consumption dose, 1 for a propofol amount 1000-2000 mg and 2 for a propofol amount > 2000 mg). We simplified the formula further as Ce ROC = 0.87 - 0.06 × age + 0.18 × Ce LOC. In conclusion, Ce ROC can be predicted under TCI with propofol- and fentanyl-based TIVA. The confounding factors that predicted propofol Ce ROC are age, sex, Ce LOC, and total consumption dose of propofol and fentanyl.

Eclampsia Following Cesarean Section with HELLP Syndrome and Multiple Organ Failure

We present a rare case of postpartum eclampsia with overt acute heart and renal failure, in the absence of any precursive signs of preeclampsia. A 41-year-old parturient underwent elective cesarean section for the delivery of twins under spinal anesthesia. Prior to the procedure, preoperative laboratory examination revealed only traceable proteinuria but she had hypertension perioperatively. Approximately 8 hours after the cesarean section, she developed seizures, followed by evident acute heart and renal failure. The diagnosis of postpartum eclampsia with HELLP (hemolysis, elevated liver enzymes and low platelets) syndrome was established and she was admitted to the surgical intensive care unit for close care. Fortunately, the patient recovered fully and was discharged 26 days later. From this illustrative example, unexplainable and sustained hypertension following cesarean section should serve as a signal to warn the health care staff concerned about the possibility of impending life-threatening postpartum eclampsia.

Analysis of anesthesia-controlled operating room time after propofol-based total intravenous anesthesia compared with desflurane anesthesia in gynecologic laparoscopic surgery: A retrospective study

Background: Anesthesia technique may contribute to the improvement of operation room (OR) efficiency by reducing anesthesia-controlled time (ACT). We compared the difference between propofol-based total intravenous anesthesia (TIVA) and desflurane (DES) anesthesia for gynecologic laparoscopic surgery undergoing general anesthesia. Materials and Methods: We performed a retrospective study using data collected in our hospital to compare the ACT of gynecologic laparoscopic surgery using either TIVA via target-controlled infusion (TCI) with propofol/fentanyl or DES/fentanyl-based anesthesia between January 2010 and December 2011. The various time intervals (waiting for anesthesia, operation time, anesthesia time, emergence time, exit from OR after extubation, total OR time and postanesthesia care unit stay time) and the incidence of prolonged extubation (≥15 min) were compared between the two anesthetic techniques. Results: We included data from 926 patients, with 377 patients receiving TIVA and 549 patients receiving DES. The only significant difference is emergence time, TIVA was faster than the DES group (7.3 ± 3.3 min vs. 8.3 ± 3.1 min; P < 0.001). The factors of prolonged extubation are DES anesthesia, body mass index, surgical time, and anesthesia time. Conclusion: In our hospital, propofol-based TIVA by TCI provide faster emergence compared with DES anesthesia in gynecologic laparoscopic surgery.

Planning for operating room efficiency and faster anesthesia wake-up time in open major upper abdominal surgery

Abstract Reducing anesthesia-controlled time (ACT) may improve operation room (OR) efficiency result from different anesthetic techniques. However, the information about the difference in ACT between desflurane (DES) anesthesia and propofol-based total intravenous anesthesia (TIVA) techniques for open major upper abdominal surgery under general anesthesia (GA) is not available in the literature. This retrospective study uses our hospital database to analyze the ACT of open major upper abdominal surgery without liver resection after either desflurane/fentanyl-based anesthesia or TIVA via target-controlled infusion with fentanyl/propofol from January 2010 to December 2011. The various time intervals including waiting for anesthesia time, anesthesia time, surgical time, extubation time, exit from OR after extubation, total OR time, and postanesthetic care unit (PACU) stay time and percentage of prolonged extubation (≥15 minutes) were compared between these 2 anesthetic techniques. We included data from 343 patients, with 159 patients receiving TIVA and 184 patients receiving DES. The only significant difference is extubation time, TIVA was faster than the DES group (8.5 ± 3.8 vs 9.4 ± 3.7 minutes; P = 0.04). The factors contributed to prolonged extubation were age, gender, body mass index, DES anesthesia, and anesthesia time. In our hospital, propofol-based TIVA by target-controlled infusion provides faster emergence compared with DES anesthesia; however, it did not improve OR efficiency in open major abdominal surgery. Older, male gender, higher body mass index, DES anesthesia, and lengthy anesthesia time were factors that contribute to extubation time.

Comparison of Anesthesia-Controlled Operating Room Time between Propofol-Based Total Intravenous Anesthesia and Desflurane Anesthesia in Open Colorectal Surgery: A Retrospective Study

We conducted a retrospective study to investigate the anesthesia-controlled time and factors that contribute to prolonged extubation in open colorectal surgery. Using our hospital database, demographic data, various time intervals (waiting for anesthesia time, anesthesia time, surgical time, emergence time, exit from operating room after extubation, total operating room time, and post-anesthesia care unit stay time), and incidence of prolonged extubation (≥ 15 mins), were compared between patients who received desflurane/fentanyl-based anesthesia and total intravenous anesthesia via target-controlled infusion with fentanyl/propofol. Logistic regression analyses were performed to assess the association between variables that contributed to prolonged extubation. In conclusion, the anesthesia-controlled time was similar in desflurane anesthesia and propofol-based total intravenous anesthesia for open colorectal surgery in our hospital. Surgical time greater than 210 minutes, as well as age, contributed to prolonged extubation.

Difficult Removal of an Epidural Catheter in the Anterior Epidural Space

When administering postoperative acute pain services, particularly regarding patient- controlled epidural analgesia, difficulties may occasionally be encountered during removal of the epidural catheter. In this report, we present an instance of difficult removal of epidural catheter in a female patient undergoing open reduction and internal fixation of the femoral neck with patient-controlled epidural analgesia as the means of postoperative pain control. The patient had satisfactory analgesia for 3 days; however, during the removal of the epidural catheter, difficulties were encountered and epidurogram revealed that the epidural catheter had become anchored in the anterior epidural space without kinking or knotting. Subsequently, the patient was requested to lie prone on the surgical table with a pillow placed beneath her lower abdomen and catheter removal was tried again. Fortunately, the epidural catheter was removed easily without the need for a guided stylet. We believe that the cause of the difficult removal of the epidural catheter in this case might have resulted from an unusual and unwanted deeper anchorage of the catheter along the anterior epidural space during placement. We also include some discussion on the management of problematic removal.