Sir, Anaesthesia for patients with isolated tetralogy of Fallot (TOF) or late presenting congenital diaphragmatic hernia (Lp-CDH) can be challenging.[1,2,3] No publications on anaesthetic care of patients with concurrent TOF and Lp-CDH were found on thorough literature search. During pre-anaesthetic evaluation, the patient, a male baby (1-year-old, weighing 7 kg) with TOF was conscious, but irritable and crying, with a regular pulse rate of 150/min, blood pressure (BP) of 90/50 mmHg and peripheral oxygen saturation (SpO2) of 70% on room air. Results of investigations carried out in the pre-operative as well as intra-operative period are shown in Table 1. Table 1 Result of laboratory and imaging studies of the patient On the morning of surgery, prophylaxis against infective endocarditis and scheduled dose of oral propranolol were administered. Premedication was achieved with ketamine 5 mg, glycopyrrolate 70 μg and midazolam 1 mg through the pre-existing 24 G peripheral intravenous (IV) catheter. Mask ventilation and subsequent tracheal intubation were carried out 3 min after administration of ketamine 15 mg, fentanyl 15 μg and vecuronium 1.0 mg IV. End tidal CO2 (ETCO2) was maintained in the range of 27-40 mmHg (tidal volume 60 ml, respiratory rate 22-26/min) with peak airway pressure of 20-24 hPa. A few minutes into the tracheal intubation, his heart rate (HR) increased to 170/min and SpO2 rapidly decreased to 63% and invasive BP (measured at right radial artery) was 100/56 mmHg. At this point of time, ETCO2 was 40 mmHg with normal waveform and auscultation of bilateral lung fields suggested equal ventilation. Isoflurane concentration was increased with not much improvement but subsequent esmolol 3.5 mg IV bolus administration improved SpO2 to 90% and HR settled at 148/min. Anaesthesia was supplemented further with another bolus of fentanyl and regular top up of vecuronium; a nasogastric tube was inserted nasally. Another intra-operative episode of low SpO2 and ETCO2 with tachycardia and normotension did not respond to supplemental dose of fentanyl 15 μg IV. It subsequently responded to RL 70 ml and esmolol 3.5 mg IV bolus administration. The right-sided Bochdalek hernia was repaired through a right subcostal incision and ropivacaine 0.2% (10 ml) was infiltrated in the subcutaneous tissue of the incision site. He was extubated tracheally at the end of surgery. The results of arterial blood gas analysis at different points of time are shown in Table 1. Immediate post-operative period was complicated by another episode of desaturation with tachycardia and normotension that responded to esmolol 3.5 mg and RL 60 ml IV administration. He was discharged in stable condition on the ninth post-operative day, no significant improvement of SpO2 was noted. Peri-operative haemodynamic goals (e.g., maintenance of normovolaemia, avoidance of decrease in systemic vascular resistance and increase in pulmonary vascular resistance) and management of hypercyanotic spell in patients with TOF has been well described.[1,2,3] The first and the last hypercyanotic spell in this case was presumed to be because of increased sympathomimetic activity arising from tracheal intubation and extubation, respectively, leading to right ventricular tract (RVOT) obstruction. As sudden decrease of ETCO2 may be seen in both RVOT obstruction and myocardial depression, we did not increase the concentration of isoflurane during the second hypercyanotic spell. Instead, we administered fluid bolus and supplementary dose of fentanyl. In all the instances, esmolol was used due to persistent tachycardia. Although pre-operative aspiration of stomach contents in patients with Lp-CDH has been recommended, it was not used and we proceeded with gentle mask ventilation, as stomach was intra-abdominal [Figure 1a].[4] Moreover, there was a high chance of precipitating a hypercyanotic spell during its insertion. Use of double lumen endotracheal tube has been suggested, but we proceeded with single lumen endotracheal tube as pre-operative chest X-ray [Figure 1b] showed a comparatively well aerated right lung.[5] Figure 1 (a) Barium upper gastrointestinal tract radiography (1) Stomach at normal intra-abdominal position (red thin arrow), (2) Few segments of small bowel loops are seen in the right hemithorax (green thin arrow), (3) Cardiac shadow (blue thin arrow). (b) Chest ... We hope that description of this unusual clinical situation and our management strategies will help to identify key clinical management issues and serve to compare outcome in patients who may suffer from similar comorbidities. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
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Oct 10, 2024
Faiz Rasool + 4
Open Access