Dexmedetomidine- A Wonder Drug in Patients With Von Recklinghausen Neurofibromatosis During Scoliosis Correction Surgery

Abstract

BACKGROUND Scoliosis, a major surgery conducted under general anaesthesia causes significant neuroendocrine stress response. Conduct of the wake-up test may further exaggerate the stress response due to the uncomfortable prone position during surgery and also presence of an endotracheal tube in situ during conduct of the test. Dexmedetomidine causes modulation of catecholamine release, which minimises the neuroendocrine and haemodynamic stress response. MATERIALS AND METHODS50 cases of NF-1 coming for scoliosis repair were studied over 4 years prospectively for quality of wake-up test, control of blood loss and haemodynamic stability due to administration of Dexmedetomidine infusion. Dexmedetomidine was started intravenously as a bolus 1 ug/ kg over 10 minutes followed by 1 ug/ kg/ hour infusion. HR, ECG, SpO2, IABP, temperature and urine output was monitored. Wake-up test: Surgeons requested for wake-up test half an hour in advance. Atracurium infusion was stopped. Isoflurane was stopped 15 mins later. Dexmedetomidine was continued at 0.5 µg/ kg/ hr. Study Design-Descriptive Study. RESULTSIn our study, we did not see any of these complications and all 50 patients had good quality of wake-up test. The patients were calm due to the hypnotic and anxiolytic actions of dexmedetomidine. They responded to commands equivalent to a Ramsay sedation scale of 2. They were pain free, haemodynamically stable with good spontaneous respiration. Intraoperative period was characterised by haemodynamic stability (Heart rate was maintained between 80 -120/mins, ABP-70/ 40 -100/ 60 mmHg, P-max 20 -24 mmHg). Average blood loss was around 15 mL/kg body weight. Major blood loss requiring massive blood transfusion was not seen; 1 unit of packed cells was transfused in each of the 50 cases. CONCLUSIONIntraoperative dexmedetomidine use has multiple advantages in NF-1 patients undergoing scoliosis corrective surgery. A randomised controlled study is necessary to statistically evaluate the multiple benefits of dexmedetomidine.