Subarachnoid Block in a Patient With Ebstein’s Anomaly

Abstract

BACKGROUND AND OBJECTIVES:Ebstein's anomaly is one of the rare congenital heart conditions that occur due an abnormal development of the tricuspid valve with "atrialization" of the right ventricle, leading to a small effective distal portion causing poor ventricular function. It may be associated with other cardiac malformations, rhythm disturbances or even a failing heart. When these patients report for surgery, the anaesthetic considerations are serious and reports about the use of central neuraxial blockade for the same is rare. Hence this study aims to provide some knowledge and information on the use of subarachnoid block in a case of Ebstein's anomaly posted for haemorrhoidectomy. PRESENTATION: DIAGNOSIS AND MANAGEMENT: A 48year old female patient with external and internal haemorrhoids was posted for haemorrhoidectomy. She was a known hypertensive with grade 1 hypertensive retinopathy on fundoscopy and was on treatment for the same. ECG showed a WPW syndrome pattern and chest radiograph showed mild cardiomegaly. 2D echocardiography revealed a dilated right atrium and right ventricle, with apical displacement of septal tricuspid leaflet and Ebstein's anomaly. There was moderate tricuspid regurgitation. Biventricular function was good with intact septum. The ejection fraction was 65%. The patient was given a low subarachnoid block in anti-trendelenberg position in the L3-L4 interspace with a combination of bupivacaine 0.5% heavy 4.5mg and fentanyl 15mcg (Total volume of 1.2ml). There was good anaesthetization with sensory and motor blockade of the saddle area. The patient was haemodynamically stable, without hypotension, rhythm disturbances or any other untoward incident throughout the procedure and in the postoperative period. CONCLUSION: Very few reports are available on the use of subarachnoid block in patients with Ebstein's anomaly. The feared drawback with its use is the occurrence of precipitous hypotension, leading to worsening of right to left shunt when it is present. Though our patient had an associated Wolff Parkinson White syndrome, she had no additional serious conditions like septal defects with reversal of flow or cardiac failure. Hence, we considered giving a low dose saddle block in view of the site of surgery and to minimize the sympathetic blockade.