Abstract
Hemodynamic responses to intramuscular injection of 5 to 10mg (average 8.5mg) of chlorpromazine were assessed in 10 patients with acute left-sided heart failure (treated group). Left ventricular filling pressure, blood pressure, heart rate, and cardiac index were measured before the injection and for 6 hours thereafter. In 8 patients with heart failure, the same hemodynamic monitoring was performed without the injection of chlorpromazine (control group).
In treated group significant reduction of left ventricular filling pressure was observed at 5min after the injection of chlorpromazine. Left ventricular filling pressure showed a peak reduction from an average of 27.2 to 18.8mmHg (-30.8%, p<0.001) at 15min, and a significant reduction persisted for 6 hours. At 15min, mean blood pressure was reduced slightly (101 to 92mmHg, -9.0%, p<0.05) and cardiac index tended to increase slightly (2.11 to 2.28L/min/M2, +7.8%, NS). Heart rate was unchanged. Relief of symptoms of pulmonary congestion was also observed within 15min. Improvement of symptoms of pulmonary congestion was more prominent particularly in 3 patients who had severe dyspnea and stridor. In control group, left ventricular filling pressure, blood pressure, and heart rate showed no significant change over 6 hours.
The present study suggested that intramuscular injection of chlorpromazine at the dosage of 5 to 10mg showed rapid and marked clinical improvement without significant side effects and therefore its use may be indicated in patients with acute left-sided heart failure, especially in paroxysmal episodes.
