Dose-dependent attenuation of intravenous nalbuphine on epidural morphine-induced pruritus and analgesia after cesarean delivery.

Epidural morphine in patient-controlled analgesia regimens controls postoperative pain well but easily induces pruritus and other epidural morphine-related side effects. With 90 pregnant American Society of Anesthesiologists physical status II females scheduled for elective cesarean delivery, the present study was designed to evaluate the efficacy and safety profile of patient-controlled antipruritus (PCP) use of intravenous nalbuphine-based regimens for attenuation of postoperative pruritus and related side effects in combination with epidural morphine patient-controlled analgesia with regard to the quality of postoperative pain management. Patients were randomly assigned to two nalbuphine groups (5 µg/kg/hour, Group N5 or 10 µg/kg/hour, Group N10) and bolus dose of 1.6 µg/kg for PCP or the control (normal saline) group. Comparable visual analog scale scores for rest pain at each measured time interval among the three groups demonstrated that adequate pain relief was offered; however, the cumulative dose of nalbuphine administered to the patients in Group N10 attenuated the analgesic effect of epidural morphine in moving pain at POh24 only. Fewer episodes and milder severity of pruritus were observed in patients in Groups N5 and N10 at all postoperative time intervals. Epidural morphine provided good postoperative pain relief but with incommodious side effects. In addition, intravenous nalbuphine not only attenuated the incidence of pruritus but also decreased total morphine consumption. In conclusion, intravenous administration of low-dose nalbuphine (5 µg/kg/hour) for PCP maintained analgesia produced by epidural morphine and offered low pruritus incidence.

A comparison of Trachway intubating stylet and Airway Scope for tracheal intubation by novice operators: a manikin study.

The Trachway is a recently developed intubation device that resembles an illuminating stylet and incorporates a video-assisted system. This study evaluated the use of this system for tracheal intubation by novice operators. This randomized cross-over study compared the Trachway and the Airway Scope in simulated routine and difficult intubation scenarios. The difficult scenario was simulated by increasing the tongue volume of the manikin. The primary outcome measure in both airway scenarios was the time required for a successful tracheal intubation. For each scenario, the success rate, ease of intubation and operator preference were recorded for the two devices and compared. Average intubation time did not differ significantly between the Trachway and Airway Scope for the normal airway scenario (11.2 ± 6.5 vs. 9.8 ± 4.3 seconds, respectively; p = 0.07), but was significantly longer using the Trachway than with the Airway Scope on the difficult airway scenario (17.1 ± 11.1 vs. 9.5 ± 4.1 seconds, respectively; p < 0.001). The overall success rates of the Trachway and Airway Scope (96.3% and 98.6%, respectively) did not differ significantly (p = 0.13). Preference for the Airway Scope was greater in both scenarios, and particularly in the difficult airway scenario (p < 0.001). Although the devices are comparable in terms of ease of use and intubation time in normal scenarios, the ease of using the Airway Scope makes it more suitable for inexperienced operators in difficult intubation scenarios.

Modified glove fingers as an aid for safely navigating endotracheal tube through the nasal cavity and nasopharynx in difficult nasotracheal intubation.

A young female patient scheduled for orthognathic surgery under general anesthesia encountered obstacles during nasotracheal intubation in which the cuff of the nasal endotracheal tube was linearly lacerated and the tube tip impacted against the retropharyngeal wall. Repeated episodes of the event happened rendering the intubation unsuccessful. A technique using modified glove fingers was applied, which successfully protected the cuff from shearing by the sharp nasal crista and redirected the tube tip away from the retropharyngeal wall. It is a simple and applicable technique during nasotracheal intubation to prevent cuff damage and potential retropharyngeal dissection.

Comparison of auditory evoked potential index and clinical signs as indicator for laryngeal mask airway insertion.

OBJECTIVE: Auditory evoked potential (AEP) index is one of the several physiological parameters for assessing the depth of anesthesia. The purpose of this study was to investigate whether the AEP monitoring could provide a better information for assessment of anesthesia level in classic laryngeal mask airway (C-LMA) insertion than the use of clinical signs in general anesthesia with single standard dose of intravenous propofol and fentanyl. METHODS: One hundred and seventy adult patients requiring general anesthesia for minor surgery were recruited and randomized to receive AEP monitoring (group A) or judgment of clinical signs (group B) for assessment of anesthesia depth and optimal condition to insert the C-LMA. The insertion conditions, including jaw relaxation, movements, presence of airway trauma and airway reflex, successful insertion rate and induction time were recorded and compared. RESULTS: The two groups were demographically similar. In group A, baseline heart rate was slower than group B (74 ± 14 vs. 78 ± 14 beats/min, p = 0.0267) and persisted throughout the whole study period. There was no significant difference in the change of heart rate during induction of general anesthesia between both groups. The incidence of movement was reduced in group A patients with AEP monitoring in comparison with group B patients (2.4% vs. 28.2%, p < 0.0001); of the unwanted events, swallowing was 0% versus 7.1%, p = 0.0126; laryngospasm was 0% versus 4.7%, p  = 0.0430 and emergence of airway reflex was 1.2% versus 11.8%, p = 0.0050; the successful insertion rate was 100% versus 94.1%, p = 0.0232; and jaw relaxation was 83.5% versus 70.6%, p = 0.0448. There were no differences between both groups in trauma and induction time. CONCLUSION: This study demonstrated that AEP index provided better information for C-LMA insertion with higher successful rate, less emergence of airway reflex and lower incidence of movement during induction of general anesthesia with single dose of intravenous propofol and fentanyl.

Delayed airway obstruction after internal jugular venous catheterization in a patient with anticoagulant therapy.

Delayed onset of neck hematoma following central venous catheterization without arterial puncture is uncommon. Herein, we present a patient who developed a delayed neck hematoma after repeated attempts at right internal jugular venous puncture and subsequent enoxaparin administration. Progressive airway obstruction occurred on the third day after surgery. Ultrasound examination revealed diffuse hematoma of the right neck, and fibreoptic examination of the airway revealed pharyngeal edema. After emergent surgical removal of the hematoma, the patient was extubated uneventfully.

Equal volumes of undiluted nalbuphine and lidocaine and normal diluted saline prevents nalbuphine-induced injection pain.

OBJECTIVES: To determine if the intravenous co-administration of equal volumes of lidocaine and nalbuphine, with undiluted normal saline, prevents injection pain caused by nalbuphine. METHODS: Eighty adult patients who were scheduled for minor surgeries under general anesthesia delivered via a laryngeal mask airway (LMA) were enrolled in this prospective, randomized, single-blind clinical trial. In the saline group (control) (n = 40), 1 mL (10 mg) nalbuphine was diluted with 9 mL normal saline. In the lidocaine group (experimental) (n = 40), 1 mL (10 mg) nalbuphine was diluted with 1 mL lidocaine (20 mg). The two respective nalbuphine solutions were injected into the cephalic vein at a rate of 20 mL/minute (0.33 mL/second). Pain scores were categorized into five grades. Pain responses upon intravenous injection of nalbuphine, site of cannulation, size of the catheter, and hemodynamic responses to nalbuphine were also recorded. RESULTS: Overall, the median pain score of patients in the lidocaine group was lower than that of the saline group (p < 0.001). In addition, the incidence of injection pain was lower in the lidocaine group than the saline group (2.5% vs. 30%, p = 0.001). CONCLUSION: A solution of equal volumes of lidocaine and nalbuphine can decrease intravenous nalbuphine-induced injection pain.

Influence of nondepolarizing muscle relaxants on intraoperative neuromonitoring during thyroid surgery.

OBJECTIVE: The objective of this study was to find a nondepolarizing muscle relaxant to replace succinylcholine during thyroid surgery with intraoperative neuromonitoring (IONM) because succinylcholine can cause severe adverse effects. DESIGN: Prospective study of 232 patients undergoing thyroidectomies. SETTING: A tertiary medical centre. METHODS: One hundred thirty-one patients received 0.5 mg/kg rocuronium (group R) and 101 patients received 0.5 mg/kg atracurium (group A) to facilitate electromyographic (EMG) endotracheal tube insertion. EMG signals were obtained from the vagus nerve before and after dissection of the recurrent laryngeal nerve and were defined as the V1 and the V2 signal, respectively. Accelerometry (twitch [% TW]) was used to monitor the quantitative degree of neuromuscular transmission at the adductor pollicis muscle. MAIN OUTCOME MEASURES: The amplitude (muV) of the V1 and V2 signals and the correlated degree of neuromuscular transmission (% TW). RESULTS: V1 and V2 signals were obtained from all patients successfully. The % TW at the V1 signal was significantly lower than that at the V2 signal in group R and group A. The mean recovery time from complete neuromuscular blockade to the initial twitch was 43.9 +/- 11 minutes. Only in the subgroup in which the correlated TW was 0% while eliciting the V1 signal were the amplitudes of the V1 signals significantly lower than those of the V2 signal in both groups. CONCLUSIONS: A single dose (0.5 mg/kg) of rocuronium and atracurium was feasible for IONM during thyroid surgery. This study showed that 44 minutes after administration of these two muscle relaxants is adequate for eliciting an EMG signal from the vagus nerve.

Survey of 11-year anesthesia-related mortality and analysis of its associated factors in Taiwan.

OBJECTIVE: In developed countries, the societies of anesthesiologists have published reports of anesthesia quality. However, there are still no publications on anesthesia quality in Taiwan, even though the Taiwan Society of Anesthesiologists (TSA) was founded in 1956. This study was designed to evaluate the quality of anesthesia in Taiwan using databases maintained by the TSA and the Bureau of National Health Insurance-Taiwan (BNHI-T). METHODS: The TSA published annual reports in 1995-1998 and 2002-2008 (with a 3-year interval), which included a survey on anesthesia-related mortality and morbidity, the manpower and composition of anesthesia teams, and the causes of anesthesia-related complications. Since 2002, the BNHI-T has collaborated with the National Health Research Institute-Taiwan to establish a database of health care service. To understand anesthesia quality in Taiwan, we collected data from the annual TSA surveys and the BNHI-T, and analyzed trends in anesthesia-related mortality, causes of anesthesia complications, and relative manpower composition. RESULTS: The rate of anesthesia-related mortality was 11.9 deaths/100,000 cases. More than 50% of all anesthesia-related complications were preventable. About 1500 anesthetic procedures were performed annually by each anesthesiologist in Taiwan. The ratio of anesthesiologists to nurse anesthetists was 1:3-5. CONCLUSION: Anesthesia-related mortality was about 10-fold higher in Taiwan than in the United States, Japan and the United Kingdom. Mortality related to quality of anesthesia in Taiwan must be reduced. To achieve this target, we have recommended the following six approaches: (1) decrease the workload of anesthesiologists; (2) increase reimbursement by the BNHI-T for anesthesia; (3) improve the training quality of anesthetist residents; (4) strengthen the quality of board examinations; (5) improve the training quality of nurse anesthetists; and (6) standardize monitoring procedures and equipment. Only once these measures are introduced, in combination with effective quality assurance and subjective improvement systems, can we expect an improvement in the quality of anesthesia in Taiwan.

Evaluation of risk factors for postoperative prolonged intubation in premature infants after cryotherapy for retinopathy of prematurity.

OBJECTIVE: Premature infants are more prone to cardiorespiratory complications after surgery than term infants. Risk factors for postoperative apnea include post-conception age, gestational age, postnatal age, birth weight, history of respiratory distress syndrome, bronchopulmonary dysplasia, anemia, necrotizing enterocolitis, use of opioids or nondepolarizing muscle relaxants, aminophylline use, history of apnea, body weight at operation, and pre-existing disease. The aim of this study was to identify the most important factors associated with postoperative extubation and respiratory outcomes among premature infants undergoing cryotherapy for retinopathy of prematurity (ROP). METHODS: We retrospectively analyzed the clinical records of 62 premature infants, with mean +/- standard deviation gestational age of 26.4 +/- 2.3 weeks, birth weight of 914.8 +/- 208.5 g, postconception age of 37.0 +/- 2.8 weeks, and body weight at the time of operation of 1970.0 +/- 446.8 g, who underwent cryotherapy for ROP. RESULTS: Only 17 infants were successfully extubated within 2 hours after operation. The most predictive factor for successful or unsuccessful extubation was body weight at the time of operation. CONCLUSION: Body weight at the time of operation was the most important factor associated with postoperative ventilatory support among premature infants under-going cryotherapy for ROP.

Lightwand-guided endotracheal intubation performed by the nondominant hand is feasible.

The aim of this study was to evaluate the efficiency of lightwand-guided endotracheal intubation (LWEI) performed using either the right (dominant) or left (nondominant) hand. Two hundred and forty patients aged 21-64 years, with a Mallampati airway classification grade of I-II and undergoing endotracheal intubation under general anesthesia, were enrolled in this randomized and controlled study. Induction of anesthesia was initiated by intravenous administration of fentanyl (2 microg/kg) and thiopentone (5 mg/kg), and tracheal intubation was facilitated by intravenous atracurium (0.5 mg/kg). In the direct-vision laryngoscope group (group D; n = 80), the intubator held the laryngoscope in the left hand and inserted the endotracheal tube (ETT) into the glottic opening with the right hand. In the group in which LWEI was performed with the right hand (group R; n = 80), the intubator lifted the patients' jaws with the left hand and inserted the ETT-LW unit into the glottic openings with the right hand. On the contrary, in the group in which LWEI was performed with the left hand (group L; n = 80), the intubator lifted the jaws with the right hand and inserted the ETT-LW unit with the left hand. Data including total intubation time, the number of intubation attempts, hemodynamic changes during intubation, and side effects following intubation, were collected. Regardless of whether lightwand manipulation was performed with the left hand (group L; 11.4 +/- 9.3 s) or the right-hand (group R; 12.4 +/- 9.2 s), less time was consumed in the LWEI groups than in the laryngoscope group (group D; 17.9 +/- 9.9 s) (p < 0.001). All three groups obtained success rates greater than 95% on their first intubation attempts. The changes in mean arterial blood pressure and heart rate were similar among the three groups. A higher incidence of intubation-related oral injury and ventricular premature contractions (VPC) was found in group D compared with groups L and R (oral injury: group D 8.5%, group L 1.3%, group R 0%, p = 0.005; VPC: group D 16.3%, group L 5%, group R 7.5%, p = 0.04). We concluded that LWEI performed by either dominant or nondominant hands resulted in similar efficiency, and could be a suitable alternative to traditional laryngoscopy. It is both feasible and logical for an experienced anesthesiologist to use the nondominant hand to perform LWEI.

Clinical experience of pain treatment for postherpetic neuralgia in elderly patients.

BACKGROUND: Postherpetic neuralgia (PHN) is a neuropathic pain syndrome that occurs following acute herpes zoster infection. The main clinical problem is intractable pain which interferes with activity of daily life and reduces the quality of life in the elderly patients. This retrospective study was to evaluate the outcome of pain treatment for the elderly patients with PHN at the Pain Clinic of Kaohsiung Medical University Hospital. METHODS: Fifty-eight elderly outpatients with PHN were studied from January 2004 to June 2006. The pain intensity before and after treatment were assessed by patients themselves with numeric pain scale (NPS). The pain treatment included (1) medication with anticonvulsants, opioids and nonsteroidal anti-inflammatory drugs (NSAIDs); (2) nerve block with 0.25% bupivacaine or 1% lidocaine twice a week at the beginning of the treatment. The therapeutic outcome was expressed by pain relief. The reduction of pain and residual pain intensity were evaluated subjectively by the patients themselves with patients' global impression and NPS, respectively, after treatment for one and three months (or last visit). The adverse events throughout the treatment course were analyzed. RESULTS: (1) The mean age of the patients was 75.1 yr. The number of female PHN sufferers was higher than that of male in all aged groups and the highest incidence was found in the age group of 70-79 (65.5%). The most commonly involved dermatomes were in the thoracic region (82.7%). (2) All patients suffered from severe pain (NPS 8-10) before treatment. (3) The pain management was a combination of medication and nerve block at the beginning of the treatment. Among the medications, gabapentin was prescribed to all the patients and almost all of them (98.3%) required opioids simultaneously and some of them needed additional NSAIDs at the beginning of the treatment. (4) The most common adverse event was somnolence (24.1%). (5) Among the sympathetic blocks, the intercostal nerve block was performed commonly (84.5%). (6) The therapeutic outcome was expressed by pain relief. As to the reduction of pain, 46 cases (79.3%) and 57 cases (98.3%) felt moderate and much improvement after treatment for one and three months (or last visit), respectively. As to residual pain intensity, although none of them got complete pain relief, however, there were 12 cases (20.7%) and 45 cases (77.6%) felt the pain intensity was mild (NPS 1-3) after treatment for one and three months respectively. (7) There was a statistically significant decrease in the pain intensity between before treatment and after treatment for one month and three months. CONCLUSIONS: Our study results showed that the concurrent combination therapy with proper medications and appropriate nerve blocks could offer satisfactory pain relief in the majority of elderly patients with PHN.

Evaluation of the effects of caudal or cephalic epidural catheterization on the characteristics of lumbar epidural anesthesia.

BACKGROUND: The delayed and incomplete sensory block of the sacral roots in epidural anesthesia often results from too huge the size of the first sacral nerve root. To overcome the problem, the enhancement of anesthetic effect on the sacral segment by injecting the local anesthetic toward the caudal direction has been reported. Thus, in this study, we compared the anesthetic effects of epidural anesthesia by catheterization toward caudal direction with that toward cephalic direction on the areas innervated by the sacral nerve roots. METHODS: The study enrolled 45 ASA physical status I or II patients scheduled for ankle surgery or hemorrhoidectomy who were randomly and evenly divided into two groups. The epidural catheter was placed either cephalad (EU group) or caudad (ED group) and confirmed by C-arm fluoroscopy after catheter insertion. Each group finally consisted of 10 patients for ankle surgery and 10 for hemorrhoidectomy after exclusion of the ineligibles. The onset time, duration of, and recovery time from epidural anesthesia, as well as demand of intra-operative analgesic in the two groups were recorded and compared. RESULTS: No significant differences were noted in the patients' characteristics between the two groups. There were also no statistically significant differences in onset, duration, recovery time, and anesthetic level attained between the two groups. More patients in the EU group demanded analgesics during surgery than did patients in the ED group. However, there were no statistically significant differences in the rate of analgesic demand between the two groups. CONCLUSIONS: Epidural injection of local anesthetic via catheter oriented caudad or cephalad did not change the characteristics of epidural anesthesia including onset time, duration, anesthetic level, and analgesic effect on the surgical areas innervated by the sacral roots.

Lightwand-assisted intubation of patients in the lateral decubitus position.

In some situations, patients need endotracheal intubation to maintain airway patency while they are constrained in the lateral position. In this study we compared lightwand-guided intubation of 120 randomly enrolled patients placed in the supine, right, or left lateral position. Group S patients were initially placed in the supine position, and subsequent to the artificial airway having been established they were turned to the lateral decubitus position. Group R patients were initially placed in a right decubitus position during induction and intubation. Group L patients were initially placed in a left decubitus position during induction and intubation. The duration of each intubation attempt, the total time to successful intubation, and the incidence of intubation-related intraoral injury, hemodynamic changes, and postoperative sore throat and hoarseness were recorded. Intubation took a similar length of time in the supine (14.5 +/- 13.4 s), left lateral (13.3 +/- 10.2 s), and right lateral positions (15.5 +/- 13.0 s) and resulted in a similar trend in hemodynamic changes. Patients in the lateral and supine positions revealed a comparable incidence of successful first-attempt intubation, sore throat, hoarseness, oral mucosal injury, and dysrhythmia. Insignificantly more esophageal intubations were performed in the lateral position in the first attempt at intubation; however, all patients were correctly intubated shortly after reattempting intubation. We concluded that lightwand-assisted intubation is easily performed and a similar technique may be used whether the patient is in a lateral, recumbent, or a supine position. This alternative technique should be practiced and is recommended for patients who must remain in a lateral position during intubation and surgery.