Labour analgesia and anaesthetic management of a primigravida with uncorrected pentalogy of fallot: Few concerns.

Sir,

We read the case report, ‘Labour analgesia and anaesthetic management of a primigravida with uncorrected pentalogy of Fallot,’ by Dr. K. Sandhya et al.,[1] with interest. We congratulate the authors for the successful management and the nice description of such a challenging case. However, certain points regarding the management of this case are worth mentioning.

Infective endocarditis prophylaxis should have been administered one hour before the procedure. Any patient with uncorrected acyanotic heart disease undergoing genitourinary procedure should receive infective endocarditis prophylaxis.[2]

The authors mentioned ‘full cardiac monitoring,’ but did not mention any invasive monitoring used during the vulval hematoma drainage, under epidural anaesthesia. In a term pregnancy, the systemic vascular resistance (SVR) decreases by 20%. Further reduction of SVR by epidural local anaesthetics can cause hypotension and further worsen the right-to-left shunt, already present in Tetralogy/Pentalogy of Fallot. Monitoring of arterial blood pressure can help in titrating epidural local anaesthetics and managing haemodynamic alterations, with the timely use of a vasopressor, and performing arterial blood gas analysis in case of worsening cyanosis or a cyanotic spell.[34]

The authors mentioned about the ‘minimisation of sympathetic blockade by maintaining intravascular volume,’ but did not mention if any vasopressor was used or kept ready. Any degree of sympathetic blockade would decrease the SVR and could worsen the right-to-left shunt in such patients. Phenylephrine is considered to be the vasopressor of choice. It should be kept ready and used at the earliest.[35]

The authors mentioned that 10 units of oxytocin were used during labour. However, they did not discuss the adverse effects of oxytocin on the Fallot physiology. Oxytocin (particularly if given as a bolus) caused peripheral vasodilation and a decrease in SVR, thereby increasing the chance of worsening of the right-to-left shunt. We presume that it was given as slow infusion.[6]

Air embolism is a serious concern in such patients. All intravenous lines used in such patients should be equipped with a device to filter air bubbles, to prevent paradoxical air embolism.[3]