Rapid point-of-care assay of enoxaparin anticoagulant efficacy in whole blood.

There is the need for a clinical assay to determine the extent to which a patient's blood is effectively anticoagulated by the low-molecular-weight-heparin (LMWH), enoxaparin. There are also urgent clinical situations where it would be important if this could be determined rapidly. The present assay is designed to accomplish this.

Toward development of a point-of-care assay of enoxaparin anticoagulant activity in whole blood.

There is need for a rapid assay to determine the efficacy of low-molecular-weight-heparin (LMWH) in whole blood. Heparinase was used to eliminate, and thereby quantify, the anticoagulant activity of the low-molecular-weight-heparin, enoxaparin. The percent change in the clotting time of whole blood in the presence of heparinase yielded the anticoagulant contribution of enoxaparin.

Perioperative management of a patient with hereditary angioedema during off-pump coronary artery bypass graft surgery.

The case of a patient with hereditary angioedema (HAE), a rare, life-threatening disorder caused by reduced activity of the C1 esterase inhibitor, and requiring off-pump coronary artery bypass graft (OP-CABG) surgery, is presented. Perioperative management of patients with HAE who undergo complex cardiac surgical procedures are discussed, including an OP-CABG surgical approach to decrease complement activation, fresh-frozen plasma administration to increase C1 esterase inhibitor activity, and administration of reduced doses of heparin and protamine to minimize heparin-protamine complex formation.

The effect of preoperative antiplatelet/anticoagulant prophylaxis on postoperative blood loss in cardiac surgery.

Unlabelled: In this study we sought to determine whether preoperative treatment with antiplatelet and/or anticoagulant drugs influences postoperative blood loss after coronary artery bypass graft surgery. Although prophylactic treatment to prevent ischemic events preoperatively is often necessary, the treatment frequently continues until there may be a risk of increased bleeding (i.e.

Do changes in end-tidal PCO2 quantitatively reflect changes in cardiac output?

In anesthetized patients, acute decreases in cardiac output (CO) are often reflected as decreases in end-tidal CO2 tension (PETCO2), but the quantitative relationship between the changes in CO and the changes in PETCO2 is uncertain. We hypothesize that a quantitative relationship can be demonstrated if timing of the measurements in each episode of hemodynamic perturbation is standardized. In 24 patients undergoing abdominal aortic aneurysm surgery with constant ventilation, we prospectively performed 33 measurements of CO, PETCO2, and CO2 elimination (VECO2) within 10 min of hemodynamic changes.

Effects of fentanyl-diazepam-pancuronium anesthesia on heart rate variability: a spectral analysis.

The effects of induction of anesthesia with fentanyl, 62.1 +/- 7.9 micrograms/kg, diazepam, 0.

Development of a real-time algorithm for predicting sufentanil plasma levels during cardiopulmonary-bypass surgery using a systems approach.

During cardiopulmonary-bypass (CB) procedures, anesthesiologists have traditionally based the administration of narcotics on general dosage recommendations and past experience. Initial doses are usually based on body weight and supplemental amounts are given in anticipation of, or in response to, the effects of surgical stimuli. There has been considerable recent interest in using the population pharmacokinetics of narcotics to optimize the attainment and maintenance of drug plasma concentrations at analgesic target levels which will blunt the hemodynamic responses to noxious stimuli.

Critical level of oxygen delivery after cardiopulmonary bypass.

The relationship between oxygen uptake (Vo2) and delivery (Do2) was examined in 64 patients immediately after cardiopulmonary bypass. In 44 patients with lactate levels below 2.5 mmol/L, Vo2 decreased proportionally when Do2 decreased below 300 ml/min X m2.

Effects of intermittent positive-pressure ventilation on cardiac output measurements by thermodilution.

Sequential thermodilution measurements of cardiac output in mechanically ventilated patients undergoing cardiac surgery demonstrated a cyclic modulation which correlated with changes in airway pressure, and was not affected by opening the pericardium. There was no satisfactory point for single measurements, which suggests that random thermodilution measurements of cardiac output during intermittent positive-pressure ventilation should be avoided, even when triplicate measurements are performed. To estimate the mean cardiac output, at least two measurements should be made at predetermined points of the ventilatory cycle.

Critical level of oxygen delivery in anesthetized man.

Fifty-eight patients studied were anesthetized with diazepam, pancuronium, and a moderate dose of fentanyl; 99 sets of multiple hemodynamic variables were measured after sternotomy and before cardiopulmonary bypass. The relationship between oxygen consumption (VO2) and oxygen delivery (DO2) was studied. The critical value of DO2 was identified to be 330 ml/min X M2 or 8.