A prospective, randomized study of cardiopulmonary bypass temperature and blood transfusion.

BACKGROUND: We hypothesized that normothermic cardiopulmonary bypass (CPB) would be associated with decreased blood loss and allogeneic transfusion requirements relative to hypothermic CPB. METHODS: After obtaining institutional review board approval and informed patient consent, we conducted a prospective, randomized study of 79 patients undergoing CPB for a primary cardiac operation at normothermic (37 degrees C) (n = 44) or hypothermic temperature (25 degrees C) (n = 35). Blood loss and transfusion requirements in the operating room and for the first 24 hours in the intensive care unit were determined. A paired t test and rank sum tests were used. A p value of less than 0.05 was considered significant. RESULTS: The normothermic and hypothermic CPB groups did not differ in demographic variables, CPB or cross-clamp duration, heparin sodium or protamine sulfate dose, prothrombin time, or thromboelastogram results. There were no differences between the two CPB groups in blood loss or transfusion requirements. CONCLUSIONS: We found that when there was no difference in duration of CPB, normothermic and hypothermic CPB groups demonstrated similar blood loss and transfusion requirements even though other studies have shown hypothermia induces platelet dysfunction and alters the activity of the coagulation cascade.

Time to reperfusion and other procedural characteristics of emergency coronary artery bypass surgery after unsuccessful coronary angioplasty.

A databank search was performed and 148 consecutive patients (mean age 59.5 +/- 10.4 years) were identified who underwent emergency coronary artery bypass surgery at the Mayo Clinic between November 20, 1979, and February 12, 1992, immediately after unsuccessful coronary angioplasty. At the end of the angioplasty procedure, there was no anterograde coronary blood flow in the treated artery in 54%, ongoing chest pain in 78%, and hemodynamic compromise requiring intravenous vasopressor therapy in 25% of patients; 127 patients (86%) had at least 1 of these adverse characteristics. After leaving the catheterization laboratory, the median time to arrival in the operating room was 12 minutes. Median time from arrival in the operating room to initiation of cardiopulmonary bypass was 86 minutes, to administration of cardioplegia was 98 minutes, and to removal of the aortic cross-clamp was 135 minutes. In-hospital mortality was 11%, and 18% developed nonfatal Q-wave myocardial infarction. Thus, significant time is required to achieve surgical reperfusion after unsuccessful coronary angioplasty.

Carbamazepine therapy in restless legs. Discrimination between responders and non-responders.

One hundred and seventy-four patients suffering from restless legs were included in a double-blind trial. Eighty-four patients were treated with carbamazepine (CBZ) and 90 with placebo. Discrimination analysis was carried out in order to characterize the patients who did not benefit from the treatment. Patients treated with CBZ were divided into responders and non-responders. A discriminant function classified 15 out of 19 actual non-responders as non-responders and 60 out of 65 actual responders as responders. By using the "leaving-one-out" technique, 14 of the non-responders and 57 of the responders were still correctly classified. The probability of erroneously classifying a patient increased from about 10 to 15% by this correction. The discriminant function classified approximately 80% of the patients in the placebo group as responders to CBZ.

Treatment of the restless legs syndrome with carbamazepine: a double blind study.

One hundred and seventy four patients suffering from the restless legs syndrome were examined in a double blind, between patient, placebo controlled study in general practice for five weeks to investigate the effects of carbamazepine and placebo on the syndrome. The syndrome was more common among middle aged women with relatively low systolic blood pressure. The median haemoglobin concentration was about average for the population, but the severity of the symptoms seemed to increase with decreasing concentrations of haemoglobin. Both placebo and carbamazepine showed a significant therapeutic effect (p less than 0.01). Carbamazepine was significantly more effective than placebo (p less than or equal to 0.03). The significant therapeutic effect of placebo in restless legs showed that only double blind controlled trials can confirm the efficacy of suggested treatments.

Comparative trial of Tenormin (atenolol) and Inderal (propranolol) in migraine.

Atenolol, 50 mg, b.i.d., and propranolol, 80 mg b.i.d.,. were given to 28 patients with a presumed diagnosis of migraine, in a placebo-controlled double-blind cross-over study, where each period lasted 6 weeks. In the total material, atenolol was significantly better than placebo in reducing attacks, whereas propranolol showed no definite such effect. In seven patients the number of headache days was remarkably high (average: 22 headache days in 42 days), which may indicate that they have been inappropriately included in the material or have recorded interparoxysmal headache in addition to attacks. If these patients are excluded, the attack-reducing effect of propranolol and tenormin is significant and of equal magnitude.

Short-term clinical trial of phopranolol in racemic form (Inderal), D-propranolol and placebo in migraine.

Propranolol penetrates the blood brain barrier, whereas mainly the racemic form, Inderal, possesses beta-receptor blocking properties. A comparison between d-propranolol and Inderal might therefore indicate the relative importance of the beta blocking properties and possible "central" effects mediated by propranolol and of importance in migraine prophylaxis. The effects of propranolol in racemic form (Inderal) 40 mg q.i.d., d-propranolol 40 mg q.i.d. and placebo were compared in 20 migraine patients. Inderal as well as d-propranolol were significantly superior to placebo. Inderal seemed to be more effective than d-propranolol, but the difference was not statistically significant (P greater than 0.05). The results indicate that beta-receptor blocking properties, but possibly also properties other than the beta-blocking ones, may be of importance for the anti-migraine effect of propranolol.

Clonidine (Catapresan)-double-blind study after long-term treatment with the drug in migraine.

A double-blind, cross-over study with clonidine (Catapresan) and placebo was carried out in 29 patients with migraine, who had received clonidine during a 4 to 32 months pre-test period (mean 10 months) and who appeared to have benefited from the treatment. Clonidine and placebo were given for 7 weeks each, but only the last 5 weeks in each period were used for the statistical evaluation. In the entire material, clonidine was significantly superior to placebo. In nine of the patients, however, various other factors might have influenced the attack frequency and severity. If these nine patients were excluded, no statistically significant difference between clonidine and placebo was found.