Author(s): Saravanan Jagannathan1, Sathyan Natarajan2, Bhavani Muthukrishnan3, Murugan Thalaiappan4

Hypotension is the most common complication during spinal anaesthesia. This study is aimed to investigate the effects of dopamine on the intraoperative haemodynamics in patients undergoing surgeries under spinal anaesthesia.
This is a randomised control study including 120 patients undergoing elective surgeries under spinal anaesthesia. Patients were randomly assigned into 4 groups (n=30 per group): Group A, Group B, Group C and Group D to receive intravenous dopamine infusion @ 0, 3, 5, and 7 mcg/kg/minute respectively. Pulse rate, blood pressure, mean arterial pressure, ECG, SpO2 were recorded at varying intervals [T1 (1st minute), T2 (2nd minute), T3, T4, T5] then every 5 minutes up to 30 minutes, then every 10 minutes till the end of the surgery. Urine output was measured every 60 minutes.
When systolic blood pressure was compared between group A and the other 3 groups, there was significant statistical difference between group A and C, A and D, from T2 to T90 minutes. Mean arterial pressure of the three groups B,C and D, compared with control group A, there was statistically significant difference seen between the groups A and C (T2-T100), A and D (T3, T10-T40). Diastolic blood pressure of the control group was compared with the other three groups B, C and D, there was no significant difference statistically. The heart rate of group A is compared with other three groups, there was no consistent statistical difference till T30 in group A vs. C, A vs. D, but after T30 minutes, there was significant fall in the heart rate in group A when compared to other 3 groups. There was a significant difference in urine output noted between the control group A and groups which received dopamine infusion. The average volume of urine in control group is 73.9 mL at the end of 60 minutes, but it was around 10 times more in group B, C and D.
Continuous intravenous infusion of 5 μg/kg/min. dopamine is safe and effective in maintaining hemodynamic stability in patients undergoing surgeries under spinal anaesthesia.