Converting continuous insulin infusion to subcutaneous insulin glargine after cardiac surgery using percentage-based versus weight-based dosing: a pilot trial.

BACKGROUND: Most studies report using percentage of total daily insulin (TDI) for converting therapy from continuous insulin infusion to subcutaneous insulin in cardiac surgery patients. Few studies have evaluated the efficacy of using body weight to calculate the basal insulin dose. OBJECTIVE: To compare the efficacy and safety of dosing insulin glargine by weight versus percentage of TDI in cardiac surgery patients transitioning from continuous insulin infusion to subcutaneous insulin. METHODS: We conducted a prospective, randomized, open-label, pilot study. Study patients who had a preoperative weight less than 100 kg and were receiving at least 6 hours of a continuous insulin infusion were randomized to receive either 50% of their TDI requirement or 0.5 units/kg of glargine as a one-time dose 2 hours before stopping the continuous insulin infusion. All patients were administered subcutaneous corrective insulin. Blood glucose monitoring occurred before each meal, at bedtime, and with morning laboratory tests for 24 hours after administration of the glargine dose. RESULTS: A total of 200 blood glucose measurements were performed in each group. The percentage of blood glucose measurements in target range (80-140 mg/dL) was similar between the weight-based group and the percentage-based group (66% vs 64%, p = 0.75). Median blood glucose after transition was 120 mg/dL (interquartile range [IQR] 99-147) in the weight-based group compared to 127 mg/dL (IQR 107-149; p = 0.03) in the percentage-based group. The median glargine dose was higher in the weight-based group (41 units; IQR 36-44) than in the weight-based group (24 units; IQR 14-30, p < 0.001). The rate of hypoglycemia (blood glucose <60 mg/dL) was 2.5% in each group. CONCLUSIONS: In this small cohort, dosing insulin glargine by weight proved to be safe, but larger scale studies are needed before adopting weight-based dosing in this patient population.

Sustained reduction in methicillin-resistant Staphylococcus aureus wound infections after cardiothoracic surgery.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) wound infections after cardiac surgery have increased in recent years and carry significant morbidity and mortality. In our hospital, MRSA accounted for 56% of postoperative infections. METHODS: Postoperative wound infection rates were compared for the 3 years before (baseline period) and after (intervention period) introduction of a comprehensive MRSA intervention program. The intervention included preoperative screening for MRSA colonization, administration of intravenous vancomycin prophylaxis for identified carriers, administration of intranasal mupirocin calcium ointment to all patients regardless of colonization status for 5 days beginning the day before surgery, and application of mupirocin to chest tube sites at the time of removal. RESULTS: Postoperative MRSA wound infections decreased by 93% (32 infections per 2767 cases in the baseline period vs 2 infections per 2496 cases in the intervention period; relative risk, 0.069; P < .001). Overall wound infection rates decreased from 2.1% to 0.8% (59 infections per 2769 cases vs 20 infections per 2496 cases; P < .001). During the intervention period, there was no change in the number of MRSA infections after noncardiac surgery. CONCLUSION: This MRSA intervention program, in which all patients receive intranasal mupirocin and patients colonized with MRSA receive vancomycin prophylaxis, has resulted in a near-complete and sustained elimination of MRSA wound infections after cardiac surgery.

A comparison of bivalirudin to heparin with protamine reversal in patients undergoing cardiac surgery with cardiopulmonary bypass: the EVOLUTION-ON study.

OBJECTIVES: Unfractionated heparin and its antidote, protamine sulfate, allow for rapid and reversible anticoagulation during cardiac surgery with cardiopulmonary bypass, yet limitations exist, including a variable dose-response, dependence on a cofactor for anticoagulant effect, and antigenic potential. This trial was performed to evaluate the safety and efficacy of bivalirudin as an alternative to heparin with protamine reversal in on-pump cardiac surgery. METHODS: We conducted a randomized, open-label, multicenter trial comparing heparin with protamine reversal to bivalirudin in patients undergoing cardiac surgery with cardiopulmonary bypass. The primary objective was to demonstrate comparable rates of in-hospital procedural success defined as freedom from death, Q-wave myocardial infarction, stroke, or repeat revascularization. Twenty-one institutions enrolled 101 patients randomized to bivalirudin and 49 patients to heparin treatment. RESULTS: The primary end point of procedural success was not significantly different between the bivalirudin arm and the heparin/protamine arms at 7 days, 30 days, or 12 weeks' follow-up. Adequate anticoagulation was achieved in all patients. Secondary end points including mortality, 24-hour blood loss, overall incidence of transfusions, and duration of surgery were similar between the two arms. CONCLUSIONS: Bivalirudin is a safe and effective anticoagulant for patients undergoing a wide range of cardiac surgical procedures with cardiopulmonary bypass. Procedural success rates with bivalirudin were similar to rates in patients receiving heparin anticoagulation, with no difference in mortality. Avoidance of blood stasis and attention to the intraoperative medical management of patients is critical for successful use of bivalirudin during cardiopulmonary bypass.