PERIPARTUM CARDIOMYOPATHY AND ANAESTHESIA (A Case Report) Lt Col PM VELANKAR·, Dr MARY SAMUEL+, Maj G SHENOY#, Lt Col CP ROY·· ABSTRACT

Anaesthetic management for caesarean section in a case of peripartum cardiomyopathy is reported. Vario~ anaesthetic problems in such a case are discussed. MJAFI 1994; 50 : 221-222

KEY WORDS: General anaesthesia; Peripartum cardiomyopathy; Lower segment caesarean section

Introduction ardiomyopathies are a group of cardiac diseases characterised by myocardial dysfunction unrelated to usual causes [1]. Peripartum of heart diseases cardiomyopathy is a rare but distinct entity of unknown aetiology [2]. It usually presents first time in the last trimester of pregnancy [3,4]. Peripartum cardiomyopathy is usually of dilated type and may present with congestive heart failure. These patients occasionally come for elective or emergency non-cardiac surgery and pose difficult problems for the anaesthesiologist. We report and discuss here anaesthetic management for elective lower segment caesarean section (LSCS) in a case of peripartum cardiomyopathy.

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CASE REPORT A 24 year old female patient, G3P2 weighing 50 kg was admitted to the hospital at 36 weeks gestation with clinical features of left ventricular failure (LVF). Her previous two pregnancies and deliveries were normal and uneventful. On examination. her pulse rate was 136 beats/min and BP 140/108 mm Hg. Left ventricular third heart sound and bilateral basal crepitations were audible. All laboratory investigations were normal except Hb 8 gm/dl and PCV 23%. Chest X-ray revealed. gross cardiomegaly with signs of pulmonary vascular hypertension. ECG showed left ventricular hypertrophy with strain. Two dimensional echocardiography revealed dilated left ventricle with poor myocardial contractility.

ejection fraction of 21%. dilated left atrium and large mitral valve orifice with mild mitral regurgitation. The diagnosis of dilated cardiomyopathy with left ventricular failure was confirmed by the cardiologist and the obstetrician planned to terminate her pregnancy by LSCS immediately after controlling her left ventricular failure. Following digitalis, diuretic. vasodilator, oxygen therapy and bed rest clinical picture of LVF improved in four days. Her BP was 130/90 mm Hg and pulse rate 116120/min. The lungs became clear. She was taken up for LSCS the next day. . On the day of operation the diuretic was omitted. On the operation tables she was positioned supine with head raised on a pillow, and a wedge under the right flank to prevent supine hypotensive syndrome. A slow intravenous infusion of Ringer's lactate (10-15 drops/min) was established. ECG, pulse oximeter and BP cuff were connected. The patient was oxygenated. Anaesthesia was induced with slow intravenous injection of morphine 3 mg and diazepam 5 mg, supplemented by 75 rng thiopentone followed by vecuronium bromide 0.15 mg per kg body weight for tracheal intubation which could be achieved in 50 seconds. Anaesthesia was maintained with nitrous oxide, oxygen (50 : 50) and controlled ventilation using Mapleson 0 circuit. During operation, pulse rate, arterial oxygen saturation (SaOz), BP, ECGand end tidal COz (ETC.Dz) w~re closely monitored and were stable. There were no cardiac arrhythmias. Before delivery of the baby, frusemide 20 mg was injected intravenously to promote diuresis and the patient was put in slight anti-Trendelenburg position to facilitate pooling of blood to periphery to reduce ven-' tricular preload and to compensate for sudden autotransfusion of uteroplacental blood into general circulation following delivery and uterine contraction. A male baby was born with Apgar score of 7/10, who cried following

• Reader, Department of Anaesthesiology, + Post Partum Anaesthesiologist, # Sr. Trainee in Anaesthesiology, AFMC, Pune 411 040.•• Classified Specialist in Cardiology, CH (SC)Pune 411 040.

222 PM VELANKAR, et 01 resuscitative measures and without need for intubation or naloxone. After delivery' slow intravenous infusion of 5 units pitocin in 500 ml dextrose was started to maintain uterine tone and minimise PPH. Induction-delivery time was 8 minutes and operation time 45 minutes. At the end of the operation neuromuscular block was reversed with slow intravenous administration of neostigmine -glycopyrrolate in conventional doses. The patient was extubated after gentle oro-pharyngeal suction. The patient was oxygenated before and after extubation. The reversal and recovery from anaesthesia was complete and uneventful. The patient was shifted to ICU for continuous ECG monitoring and postoperative management. She was given oxygen inhalation by nasal catheter. morphine 3 mg IVas and when required for analgesia. and IVfluids upto 1.5 litre per day for first 48 hours. The postoperative course was uneventful. Her cardiac condition improved dramatically. She was discharged from hospital three weeks later.

Discussion The principles of anaesthetic management in cardiomyopathy are - avoiding drug induced myocardial depression or cardiac dysrhythmias, reduction of both preload and afterload to lessen the work required of failing heart and maintaining normovolaemia. Volume overload must be avoided. These patients may also have slow circulation time [1]. Therefore all sedative and anaesthetic drugs must be given slowly and sufficient time interval allowed before giving additional dose. Otherwise there is a risk of administering overdose of these drugs which may result in. myocardial depression. In this case induction of anaesthesia was done with small doses of morphine and diazepam supplemented by only 75 mg of thiopentone. All these drugs were given slowly' intravenously. Morphine and diazepam have respiratory depressant action on foetus, therefore they are contraindicated in LSCS before delivery of the baby. However, we have used these drugs in small doses because they do not cause myocardial depression and therefore do not reduce cardiac output further which is already low in these patients. Though we kept naloxone ready at hand to counteract the effect of morphine in newborn, it was not required and there was

MJAFI, 50 : 3, JULY 1994

no difficulty in resuscitation of the newborn. We used vecuronium, a non-depolarizing muscle relaxant, in this case. This drug has an onset of action of 3 minutes and is cardiostable even in large doses. Moreover, it has been shown that with prior administration of diazepam, vecuronium 0.15 mg/kg is a suitable relaxant for rapid sequence intubation and provides adequate intubating conditions at 60 seconds [5]. In this case we could intubate the patient in 50 seconds. Suxamethonium, though considered ideal for tracheal intubation in LSCS cases was not used in this case because of its well known cardiac side effects [6]. Throughout the operation we took utmost precautions to maintain normocapnia and avoid volume overload. CVP and pulmonary artery pressure monitoring are ideal in this situation but these facilities were not available in our operation theatre. Epidural anaesthesia has been successfully used for noncardiac surgery in patient of dilated cardiomyopathy [7]. We did not use epidural anaesthesia in this case because of our limited experience with this technique in cardiac patients. REFERENCES 1. Stoelting RK. Stephen F. AnClesthesia and co-existing disease. ard ed. New York: Churchill Livingstone. 1993; 97-102. 2. Pierce JA.Price BD.Joyee JW. Familial occurrence of post partal heart failure. Arch Intern Med 1963; 111 : 651-5. 3. Demak JG.Rahimtoola SH. Sutton GC. et al. Natural course of peripartum cardiomyopathy. Circulation 1971; 44: 1053-61. 4. Veille IC. Peripartum cardiomyopathies: a review. Am I Obstet GynaecoJ 1984; 148 : 805-18. 5. Mirakhur RK. Ferres CJ. Clarke RSJ. et al. Clinical evaluation of Org NC 45. Hi- , Anaesth 1983; 55 : 119-24. 6. Stoelting RK. Pharmacology and Physiology in Anaesthetic Practice. Philadelphia; JBLippincott Company. 1992; 174-8. 7. Amornath I. Eskandiari S. Lockrem J. Rollins M. Epidural anaesthesia for total hip replacement in a patient with dilated cardiomyopathy. Can Anaesth Soc, 1986; 33 : 84-8.

PERIPARTUM CARDIOMYOPATHY AND ANAESTHESIA (A Case Report).

Anaesthetic management for caesarean section in a case of peripartum cardiomyopathy is reported. Various anaesthetic problems in such a case are discu...
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