Prolonged neuromuscular block in a patient undergoing renal transplantation.

Prolonged neuromuscular block is an anesthetic complication that every anesthesiologist should understand. This article presents a case of prolonged neuromuscular block in a renal transplant patient that was likely due to pseudocholinesterase deficiency. The different types of pseudocholinesterase deficiency and their clinical implications are reviewed. Also discussed are the workup and other causes for prolonged neuromuscular blockade.

Diltiazem to treat sinus tachycardia in critically ill patients: a four-year experience.

OBJECTIVES: To determine whether an intravenous infusion of the calcium channel blocker diltiazem was effective and safe in treating sinus tachycardia in critically ill adult patients with contraindications to beta-blockers or in whom beta-blockers were ineffective. DESIGN: Retrospective chart review. SETTING: University medical center. PATIENTS: The records of 171 surgical intensive care unit patients with sinus tachycardia treated with intravenous diltiazem were evaluated. INTERVENTIONS: In all patients with sinus tachycardia (heart rate >100 beats/min), heart rate control with intravenous diltiazem was attempted after adequate intravascular volume expansion, pain, and anxiety control. In all patients, beta-blockade either was contraindicated or (in 7%) had failed. Intravenous diltiazem was administered as a slow 10-mg bolus dose (0.1-0.2 mg/kg ideal body weight), and then an infusion was started at 5 or 10 mg/hr and increased up to 30 mg/hr, as needed, to decrease heart rate to <100 beats/min. Variables retrospectively collected included demographic data, preinfusion blood pressure, mean arterial pressure, heart rate, and preinfusion pressure-rate quotients (pressure-rate quotient = mean arterial pressure / heart rate). Intravenous bolus dose, when given, and diltiazem infusion rate and time necessary to achieve the target heart rate also were recorded. The lowest heart rate recorded within 24 hrs from the initiation of the infusion and the time necessary to achieve the lowest heart rate after beginning the infusion were recorded. MEASUREMENTS AND RESULTS: Of 171 patients studied, 97 (56%) were classified as responders. Multiple linear regression suggested that response could be predicted by age, pressure-rate quotients, baseline mean arterial pressure, and central nervous system failure. In the responders, a heart rate <100 beats/min was achieved in an average of 2 hrs, at a mean diltiazem infusion of 13.3 mg/hr. The lowest rate reached by the responders in a 24-hr period averaged 86 beats/min and was achieved in 4.8 hrs with a mean infusion rate of 14.8 mg/hr. Both target and lowest rate values were statistically different from baseline heart rate. CONCLUSION: Diltiazem was effective in achieving short-term control of heart rate in 56% of the patients, virtually without adverse effects, where beta-blockade was contraindicated or ineffective.

Myocardial ischemia detected by transesophageal echocardiography in a patient undergoing peripheral vascular surgery.

Prevention and early treatment of myocardial ischemia remain among the primary goals of the anesthesiologist taking care of high-risk patients, such as those undergoing vascular surgery. Guidelines have been published to assist in directing preoperative evaluation and optimization of cardiovascular status. Although perioperative monitoring allows early detection of ischemic events, all monitors have limitations that must be understood before they can be used effectively. We present a case of severe intraoperative myocardial dysfunction detected only by transesophageal echocardiography in a patient undergoing a peripheral vascular procedure. Preoperative and intraoperative management is also discussed.

Transfusion therapy in the critically ill.

Blood transfusion remains an important part of treatment in critically ill patients. While the known infectious risks continue to decrease, concerns remain about the effects of allogeneic blood on the immune system. Some patients tolerate anemia much better than others; the optimal hemoglobin level, however, is difficult to define in any individual patient.