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Pancuronium is frequently used in coronary artery surgery, but its pharmacokinetics in these patients are still unknown. It is possible that dopamine, administered to prevent renal impairment induced by the surgery, might promote the elimination of pancuronium. Therefore, the pharmacokinetics of a bolus dose of pancuronium were studied in 2 groups of coronary artery surgery patients, with and without dopamine 2 micrograms/kg/min, administered during and after cardiopulmonary bypass. Dopamine in the administered dose did not influence the systemic haemodynamics. The pharmacokinetic variables in both groups did not differ from those found in an earlier study in healthy normothermic patients. Total renal clearance was not influenced by dopamine, due to post-bypass rebound hyperperfusion in the control group. Pancuronium was shown to be subject to considerable tubular reabsorption, and its elimination was found to be increased during hypothermia. Dopamine increases pancuronium elimination by an increase in glomerular filtration rate. The dopamine-induced decrease in tubular solute reabsorption did not enhance the elimination of pancuronium.

The hypotensive effect of stable plasma protein solution (SPPS) is a well-known phenomenon, causing serious problems in surgical patients and patients supported by cardiopulmonary bypass. Kinins are believed to be responsible. A study was made to prevent this hypotension by adding C1 esterase inhibitor to the SPPS and comparing this with 5% human albumin. The results shows a significant difference between the effects of SPPS and SPPS plus C1 esterase inhibitor infusion on bypass. Five percent human albumin did not cause hypotension. Possible sequelae are discussed.

Ketanserin, a selective S2-serotonergic receptor antagonist with alpha 1-adrenergic receptor-blocking properties, as well as nifedipine, a classic calcium channel blocker, is used as an antihypertensive agent during and following cardiac surgery. In a double-blind prospective study, using hypothermic cardiopulmonary bypass as a study model, ketanserin (10 mg i.v.) and nifedipine (2 mg i.v.) were evaluated with respect to their effects on the peripheral circulation. The results showed that ketanserin and nifedipine dilate the arterial side of the vasculature, but that ketanserin, unlike nifedipine, also dilates the venous capacitance vessels; nifedipine even caused a short-lasting venous vasoconstriction. Since venous tone is increased during and following cardiopulmonary bypass, antihypertensive treatment with ketanserin might be advantageous under these circumstances.

Objective Postcardiopulmonary bypass hemorrhage remains a serious complication of cardiac surgery. Given concerns regarding adverse effects of blood product transfusion and limited efficacy of current antifibrinolytics, procoagulant medications, including recombinant factor VIIa (rFVIIa) and factor eight inhibitor bypass activity (FEIBA), increasingly have been used in managing refractory bleeding. While effective, these medications are associated with thromboembolic complications. This study compared the efficacy and risk of adverse events of rFVIIa and FEIBA in cardiac surgical patients with refractory bleeding. Design This retrospective study evaluated 168 patients who underwent cardiac surgery and received either FEIBA or rFVIIa to manage postbypass hemorrhage. Demographic, clinical, and outcomes data were collected and statistical analysis performed to compare thromboembolic event rates, relative efficacy, and 30-day mortality following administration of these medications. Setting Single university hospital. Participants Patients undergoing cardiac surgery. Interventions None. Measurements and Main Result Sixty-one patients received rFVIIa, and 107 received FEIBA. Demographics, surgical procedures, and preoperative anticoagulation were similar between the cohorts; however, the rFVIIa cohort had longer durations of cardiopulmonary bypass (305.1 v 243.8 min, p<0.01). There were no significant differences in the number of thromboembolic events, 30-day mortality, or rates of revision surgery. Neither group demonstrated a clear relationship between dosage and occurrence of thromboembolic events. The rFVIIa cohort received more platelets than the FEIBA cohort (3.13 v 1.67 units, p = 0.01), but transfusion rates of other blood products were similar. Conclusions This study suggests that rFVIIa and FEIBA have similar efficacy and adverse event profiles in managing intractable postbypass hemorrhage in cardiac surgical patients. Further prospective studies are required. [ABSTRACT FROM AUTHOR]

Objectives: We sought to assess the effects of cardiopulmonary bypass and profound hypothermic circulatory arrest on plasma cefazolin levels administered for antimicrobial prophylaxis in cardiovascular surgery. Methods: Four groups (10 patients per group) were prospectively studied: vascular surgery without cardiopulmonary bypass (group A), cardiac surgery with a cardiopulmonary bypass time of less than 120 minutes (group B), cardiac surgery with a cardiopulmonary bypass time of greater than 120 minutes (group C), and cardiac surgery with cardiopulmonary bypass and profound hypothermic circulatory arrest (group D). Subjects received cefazolin at induction and a second dose before wound closure. Arterial blood samples were obtained preceding cefazolin administration, at skin incision, hourly during the operation, and before redosing. Cefazolin plasma concentrations were determined by using a radial diffusion assay, with Staphylococcus aureus as the indicator microorganism. Cefazolin plasma concentrations were considered noninhibitory at 8 μg/mL or less, intermediate at 16 μg/mL, and inhibitory at 32 μg/mL or greater. Results: In group A cefazolin plasma concentrations remained greater than 16 μg/mL during the complete surgical procedure. In group B cefazolin plasma concentrations diminished to 16 μg/mL or less in 30% of the patients but remained greater than 8 μg/mL. In group C cefazolin plasma concentrations decreased to less than 16 μg/mL in 60% of patients and were less than 8 μg/mL in 50% of patients. In group D cefazolin plasma concentrations reached 16 μg/mL in 66% of the patients but decreased to 8 μg/mL in only 1 patient. Conclusions: For patients undergoing cardiac surgery with a cardiopulmonary bypass time of greater than 120 minutes, a single dose of cefazolin before skin incision with redosing at wound closure does not provide targeted antimicrobial cefazolin plasma levels during the entire surgical procedure. Patients undergoing profound hypothermic circulatory arrest are better protected, but the described protocol of prophylaxis is not optimal. [Copyright &y& Elsevier]