Cardiovascular collapse after labetalol for hypertensive crisis in an undiagnosed pheochromocytoma during cesarean section.

Pheochromocytoma is a catecholamine-producing tumor but rarely delayingly diagnosed until during pregnancy. We reported a pregnant woman who underwent emergent cesarean section because of intrauterine growth retardation, oligohydramnios, and hypertension. The existence of an undiagnosed pheochromocytoma was suspected by the unusual hemodynamic response to spinal anesthesia, abdominal compressions, and operative stimulus. Hypertensive crisis occurred during the operation and she was sent to the intensive care unit for postoperative care. In the intensive care unit, cardiovascular collapse occurred after nonselective ß-adrenergic blockade. Unexpected hypertensive crisis during the perioperative period should alert clinicians to the possibility of a pheochromocytoma. For the treatment of choice, nonselective ß-adrenergic blockade should not be used before the α-blockade.

An analysis of patient variables that influence intravenous patient-controlled analgesic use of morphine with quantile regression.

BACKGROUND: Previous studies using linear regression analysis have shown that age, weight, gender, and the site of operation affect intravenous patient-controlled analgesia (IVPCA) narcotic use. However, there are inconsistent observations in the literature. The authors postulate that patient variables could have different effects at various doses of narcotics. To test this hypothesis, the authors analyzed the effect of patient variables on increasing doses of IVPCA narcotic with quantile regression. METHODS: The authors collected retrospective data from 1,782 patients who received IVPCA for a minimum of 3 days after surgery. The authors used stepwise linear regression model to identify variables that significantly affected the total IVPCA requirements. Quantile regression model was further applied to assess the effects of selected variables on the ascending percentile of IVPCA narcotic use. RESULTS: Gender, age, body weight, cancer, and surgical site were identified as significant predictors for IVPCA demand. Body weight had the most and cancer had the least significant effects on total IVPCA demands. The results of quantile regression model revealed that the determinants under consideration varied with different percentiles of IVPCA demand. The patient variables correlated with IVPCA narcotic use differently when the dose exceeded the seventieth to eightieth percentiles compared with other percentiles of narcotic use. CONCLUSIONS: The authors' findings highlight the heterogeneous postoperative pain requirements among patients and the consequent complex process of efficiently managing postoperative pain.

A modified supraclavicular approach for central venous catheterization by manipulation of ventilation in ventilated patients.

BACKGROUND: Because of overuse and multiple implantations of hemodialysis catheters through internal jugular or subclavian vein (SCV) in patients with chronic hemodialysis, these veins often become stenotic or occlude, therefore necessitating alternative access. We introduce a new technique in ventilated patients for placement of tunneled cuffed chronic hemodialysis catheter: modified supraclavicular approach by cease of ventilation. METHODS: Patients who received implantation of the tunneled cuffed chronic hemodialysis catheters by supraclavicular approach were collected from February 2003 to July 2005. Right subclavian, right innominate or left SCVs were accessed through the supraclavicular approach for catheter insertion. The procedures were performed by certificated anesthesiologists. The following parameters were recorded: co-morbidities, laboratory examinations before the procedure, method for catheterization, duration of procedure, complications related to catheterization and long-term outcome of hemodialysis catheters. RESULTS: Eleven catheters were inserted in nine patients (two patients received twice) by supraclavicular approach during this period. All patients were mechanically ventilated and these catheters (seven at right and four at left) were implanted using the modified supraclavicular approach with lung deflation during venipuncture, advance of guidewire, and insertion of catheter. There were no procedural complications. The average duration of whole procedure was 36.6 minutes (30-45 minutes) and the mean catheter survival days were 62.1 days (13-152 days). The estimated duration was <1 minute of each period of lung deflation. There were no desaturation or pneumothorax during the whole procedure. CONCLUSION: The modified supraclavicular approach with lung deflation for tunneled cuffed chronic hemodialysis catheter in ventilated patients is at least as effective as traditional approach and can be easily performed by surgeons as well as experienced physicians. Based on the results, this simplified technique using lung deflation may be particularly useful to decrease procedural complications.

Thoracic epidural anesthesia for a polymyositis patient undergoing awake mini-thoracotomy and unroofing of a huge pulmonary bulla.

General anesthesia with one-lung ventilation is a conventional anesthetic strategy for most chest surgery, including resection of pulmonary bullae. However, this anesthetic management may cause alveolar barotrauma, hemodynamic instability, pulmonary atelectasis and long-term ventilator dependency. Here, we report a 64-year-old female with polymyositis and bronchiolitis obliterans organizing pneumonia who was scheduled for surgical intervention for a huge pulmonary bulla over the right upper lung. Under thoracic epidural anesthesia, with the patient maintaining clear consciousness and spontaneous breathing, a mini-thoracotomy was accomplished to unroof and partially resect the bulla. There were no perioperative complications, and the patient was satisfied with the anesthetic care. Pulmonary function tests and daily physical performance also improved postoperatively.

Instructor-based real-time multimedia medical simulation to update concepts of difficult airway management for experienced airway practitioners.

BACKGROUND: We integrated lecture, real-time multimedia display and medical simulation into a new renewal airway management training protocol for experienced nurse anesthetists. METHODS: Trainees of the Taiwan Association of Nurse Anesthetists from northern Taiwan and junior residents from our department were enrolled into the training program. A 4-hour renewal curriculum in the management of airway emergencies was developed, which consisted of a 2-hour general lecture (including 4 divided sections) and a 2-hour instructor-based real-time multimedia medical simulation of 4 specific techniques. After detailed explanation of each specific instrument at the beginning of each simulation, the instructors demonstrated accurate and successful management of 4 airway crises from clinical experience by using a standardized human patient simulator situated on the stage of the conference room. Meanwhile, real-time display of instructors' performance, responsive physical parameters and images from specific instruments were conducted by video camera and video processor, and projected on a 3-frame screen. Brief summary and feedback were performed after each simulation. Trainees completed a questionnaire 6 months after they participated in the training program. RESULTS: Two hundred and forty-two nurse anesthetists and 13 young residents were trained with this protocol. The questionnaire revealed that the renewal training program was useful. Participants updated their knowledge of difficult airway management, gained more confidence, improved performance, and provided effective assistance in handling airway crises. CONCLUSION: Renewing practice guidelines and teaching airway management skills, especially for difficult airway crises and protection of personnel, continues to be an important issue. Instructor-based real-time multimedia simulation is a fast, useful and systematic renewal educational method for many participants with extensive experience of airway management to update their knowledge about difficult airway management, and acquire improved decision-making and communication capabilities, skills of specific airway management.