Pulmonary oedema in two parturients with hypertrophic obstructive cardiomyopathy (HOCM)

Abstract

Pulmonary oedema in two parturients with hypertrophic obstructive cardiomyopathy (HOES)TwoHypertrophic obstructive cardiomyopathy (HOES) is a relatively recently described abnormality which appears to be increasing in frequency.' It is observed in all races, at all ages, in both sexes and can be lethal, z-4Hypertrophic obstructive cardiomyopathy presents a major challenge to the anaesthetist managing parturients. Women in labour are stressed by the pain of labour and its associated increase in catecholamine secretion. 5 Cardiac output normally increases as a result of the catecholamine-induced increase in heart rate and stroke volume. 6 However, in patients with HOES, elevated circulating catecholamines can lead to decreased forward flow. Increased contractility leads to greater obstruction of the left ventricular outflow tract and tachycardia limits diastolic filling which reduces left ventricular enddiastolic volume. 7 The Valsalva manoeuvre, used to help the fetus descend in the second stage of labour, can also impair cardiac output in these patients through reducing preload. 2Many authors have stated that regional anaesthesia (spinal or epidural) is relatively contraindicated in the patient with HOES. 9-'1 General anaesthesia with halothane to reduce myocardial contractility and heart rate is the recommended form of anaesthesia. 9 This cannot be applied absolutely to the parturient in labour and lumbar epidural analgesia is often administered. I~ Two patients with HOCM who presented for delivery are reported. Each was managed with a different anaesthetic technique yet both developed pulmonary oedema. The discussion will focus on the pathophysiological changes in HOCM and their implications for management once pulmonary oedema has occurred. Case 1A 27-yr-old female, G3P2 was admitted to the antepartum ward at 37 weeks gestation and was scheduled for elective Caesarean section the following morning. She had had CAN J ANAESTH 1990/ 37:4 /pp469-73

Pregnancy in Patients With Pre-Existing Cardiomyopathies

“…As noted previously, tachycardia shortens the left ventricular diastolic filling period, decreasing preload, and exacerbates outflow obstruction. Moreover, performance of the Valsalva maneuver during labor and delivery, which helps the fetus descend during the second stage of labor, can also impair venous return and impairs cardiac output in patients with significant obstruction (68). A similar problem can occur in the setting of substantial blood loss during or after delivery (69).…”

“…Most women received general anesthesia out of concern for a rapid fall in systemic vascular resistance in patients with a fixed cardiac output due to the degree of outflow stenosis. Vasopressor agents and fluids can be given to treat hypotension, but it is preferable to use a pure alpha-agonist such as phenylephrine, because it lacks any inotropic properties (68). In HCM, inotropes can worsen the outflow gradient and are relatively contraindicated (51).…”

Hypertrophic cardiomyopathy and caesarean section: intraoperative use of transthoracic echocardiography

“…6 This suggests that hypovolaemia during pregnancy is of greater concern than hypervolaemia. Due to the low incidence of adverse events, especially pulmonary oedema, 7 it has not been possible to correlate symptom severity or echocardiographic findings with outcome. Absolute mortality is low, at 10 per 1000 live births, but is greater than in the non-pregnant HCM population.…”

“…Cautious fluid administration is required given that pulmonary oedema has been reported post partum in HCM patients. 7 Information from the TTE aided management decisions and was obtained non-invasively. Although the choice of anaesthetic technique for caesarean section should be made on an individual basis, TTE eliminates the need for general anaesthesia for TOE.…”

Perioperative anesthetic management of patients with hypertrophic cardiomyopathy for noncardiac surgery: A case series

“…Pulmonary edema has been observed in parturients with HCM after delivery, emphasizing the delicate fluid management in these patients. [10] CONCLUSION Three patients with HCM undergoing different surgical procedures are presented. It may be worth emphasizing that successful anesthetic management of a patient with HCM requires thorough understanding of the hemodynamic changes, proper intraoperative vigilance, avoiding factors that may increase LVOT obstruction with proper medication and intravascular fluid therapy.…”