Abstract :
Background: Cardiovascular autonomic neuropathy (CAN) is one of the least frequently diagnosed and the most clinically significant complications of Diabetes mellitus (DM). Impaired heart rate variability (HRV) is the earliest indicator of CAN. Peri-operative hemodynamic instability is a major concern during general anaesthesia (GA) in patients with autonomic dysfunction. Purpose of this study was to assess and compare the autonomic function using HRV in diabetic and non-diabetic patients pre-operatively and to study the haemodynamic responses of these patients during induction.
Objectives: The primary objective was to assess and compare the autonomic function using HRV in diabetic and non-diabetic patients preoperatively. Secondary objective was to study hemodynamic responses of these patients during induction of GA.
Materials and Methods: We included 68 patients (34 diabetics- group D and 34 non-diabetics- group N) aged between 30 to 65 years, with American society of anaesthesiologists (ASA) physical status 1 and 2 undergoing elective surgeries under GA. All the eligible patients underwent HRV evaluation for 10 minutes on the previous day of surgery and the time & frequency domain variables were evaluated. The hemodynamic parameters were recorded at pre-induction, post-induction, post-intubation and for every 3 minutes thereafter for 15 minutes and analysed.
Results: The diabetics had a significantly lower total power (TP) with p-value 0.003. The post- induction mean arterial pressures (MAP) were comparatively lower in diabetics and the difference was significant at 12 minutes post intubation (p= 0.04). The lower trends in heart rate (HR) were comparatively more in diabetics rather than non-diabetics (p= 0.06) and the ephedrine usage was also higher in diabetics (p= 0.07).
Conclusion: The measurement of HRV is a simple tool to evaluate the peri-operative risks in patients with suspected cardiovascular autonomic neuropathy.
Keyword :
Anaesthesia, Cardiac autonomic neuropathy, Diabetes mellitus, Heart rate variability, Hypotension.