Case series: Dexmedetomidine and ketamine for anesthesia in patients with uncorrected congenital cyanotic heart disease presenting for non-cardiac surgery
Case 4 was a 20-year-old female patient, a diagnosed case of TOF who presented with a frontal lobe abscess with a 12 mm midline shift and features of septic shock. She was posted for emergency craniotomy and drainage of the abscess. There was a history of occasional episodes of cyanotic spells since the last 1 year. However, she had not undergone any corrective or palliative surgery and was not on any medication. Preoperative evaluation revealed SpO286% on room air, arterial blood gas (ABG) analysis showed PaO247.8 mmHg, pH 7.465, PaCO250.3 mmHg, and HCO330 mmol/l. She was being managed with vasopressors (noradrenaline: 0.05-0.07 g/kg/min) to maintain the mean arterial pressure (MAP) above 65 mmHg. After preoxygenation, the patient was induced with dexmedetomidine 1 g/kg and ketamine 2 mg/kg over 10 min. Anesthesia was maintained on controlled ventilation with vecuronium and an infusion of dexmedetomidine (0.7-1.0 g/kg/h) and ketamine (2 mg/kg/h). Paracetamol 1 g IV was added for analgesia though no inhalational anesthetic was used for maintenance. Cardiac output and systemic vascular resistance (SVR) were monitored by FlotracTM. SVR was maintained <1,200 dyne.s/cm5 by an infusion of noradrenaline (0.05-0.1 g/kg/min). There was a large parietal abscess and about 100 ml of pus was drained. In view of the raised intracranial pressure (ICP) and septic shock, she was electively ventilated in the ICU.