Despite their proven value in reducing morbidity and mortality in different grades of heart failure, angiotensin converting enzyme (ACE) inhibitors continue to be underused. One reason for this is clinicians' apprehension of first-dose hypotension. We conducted a double-blind, randomised, placebo-controlled parallel group study to investigate the effect of various ACE inhibitors on first-dose hypotension. Eighty unselected patients were randomised into five treatment groups: placebo, captopril 6.25 mg, enalapril 2.5 mg, perindopril 2 mg and lisinopril 2.5 mg. Blood pressure was measured at baseline, half hourly for two hours and hourly for three hours after drug treatment. The maximum drops in mean arterial pressure (in mmHg +/- SD) were placebo 5.89 +/- 2.65, perindopril 5.29 +/- 2.49, enalapril 13.28 +/- 3.31, lisinopril 15.04 +/- 5.74 and captopril 16.76 +/- 5.74 (all p < 0.05 vs placebo except for perindopril). Perindopril, unlike the other ACE inhibitors studied, did not produce first-dose hypotension following its initiation in patients with congestive heart failure.
The aim of the study was to determine the effect of pro-phylactic low dose dopamine infusion on renal function in ventilated premature newborns with respiratory dis-tress syndrome (RDS). A prospective, randomised con-trolled trial was conducted, using low dose dopamine [2.5μg/kg/min] in the treatment of preterm babies with gestational age 28-36 weeks requiring mechanical ventilation for RDS within six hours of age. Thirty-six babies were enrolled and 19 babies were randomly assigned to the treatment groups. The renal function after 72 hours for the treatment and control groups respectively were: urine output (ml/kg/hour) 3.3±0.4 and 3.0±0.3 [p=0.55], urine specific gravity 1006±0.6 and 1006±1.0 [p=0.68], fractional excretion of sodium 4.1±0.8 and 2.6±0.4 [p=0.10], fractional excretion of potassium 37.44 ± 5.6 and 16.49 ± 2.2 [p=0.001], glomerular filtration rate (ml/day/1.72m2) 16±2.6 and 25.6±4.5 [p=0.06]. There were no significant differ-ences in the frequency of hypotension, oliguria and sep-sis between the two groups. There were seven deaths (36.8%) in the treatment group (six due to sepsis and one due to prematurity) and two deaths (11.8%) in the control group (both due to sepsis) (p = 0.13). In con-clusion prophylactic low-dose dopamine infusion did not improve the renal function in ventilated premature babies with respiratory distress syndrome. The results of this study do not support the routine use of prophylac-tic low-dose dopamine in ventilated preterm babies with respiratory distress syndrome.
Thrombolytic therapy is a well-established therapy in acute myocardial infarction (AMI), reducing mortality and infarct size. This study is a retrospective analysis of survival and complications after the use of streptokinase at Hospital Universiti Sains Malaysia. Streptokinase was first used here in March 1990. Between then and February 1992, 126 patients were admitted to the Coronary Care Unit. Thirty-two patients who fulfilled our criteria for thrombolytic treatment were given an hour intravenous infusion of 1.5 MU streptokinase, and started on aspirin. A control group of 64 patients selected from before March 1990, and matched for age, sex and site of infarct, was given standard therapy. The survival at 4 weeks post-AMI was 91% in the streptokinase therapy group and 91% in both groups (p > 0.05). The complications encountered were reperfusion arrhythmias (2 patients), hypotension(1), maculopapular rash(1) and gum bleeding(1). None of these complications were statistically increased when compared to the control group and none resulted in the death of a patient. We conclude that streptokinase therapy can be given safely in a rural Malaysian setting. Our survival and complication rates are comparable with other published series.
Among several alkaloids, including dimeric indoles, isolated from Uncaria callophylla, gambirine which is an alkaloid unique to this plant, has been found to be another hypotensive principle from the plant. Intravenous injections of gambirine in the dose range of 0.2 to 10.0 mg/kg caused a dose-related fall in both systolic and diastolic blood pressures as well as heart rate. At all doses gambirine showed a prompt onset of action and at the higher doses (5.0-10 mg/kg), marked persistence of hypotension accompanied by severe bradycardia were observed. In addition, higher doses of gambirine produced a more marked decrease in diastolic than systolic pressure while at lower doses both decreased equally. It is suggested that the hypotensive effect of gambirine may be peripheral in origin and is associated, at least in part, with a cardiac action.
We have evaluated the effects of a B2 receptor antagonist (B5630) of kinins on BK and captopril-induced acute hypotensive responses in anaesthetized SHR. Intravenous treatment of BK (1.0 microgram) and captopril (0.3 mg/kg) caused significant (p < 0.05) fall in the SBP and DBP. Whereas BK caused greater fall in the SBP (p < 0.05), DBP (p < 0.01) and duration of hypotension (p < 0.05) when administered after captopril (Fig 1 and 2). All the hypotensive effects of BK and captopril were significantly antagonised (p < 0.05) in the presence of B5630 (2.0 mg/kg). Further, the duration of hypotensive responses of BK and captopril were blocked (p < 0.05) by B5630. The agonists and BK-antagonist did not cause significant (p > 0.05) alterations in HR during the entire investigation. These findings provide evidence to support the suggestion that B2 receptor might be involved in the regulation of the hypotensive actions of BK and captopril. Kinins should also have valuable functions in the antihypertensive property of captopril-like drugs.
Twenty patients undergoing various surgical procedures were anaesthetised using hypotensive anaesthesia using labetalol and halothane. The technique is safe, predictable and cheap. This technique also offers the advantage of usage of less blood, thus minimising the complications of transfusion induced diseases like hepatitis and AIDS.