Intravascular Administration of Isotonic Saline versus Polymerised Gelatin in the Prevention of Spinal Induced Hypotension: A Randomised Clinical Trial UC14-UC17
Department of Anaesthesia, Father Muller Medical College, Kankanady, Mangalore 575002, Karnataka, India.
Introduction: Hypotension remains one of the most common problems associated with subarachnoid blockade. A number of strategies have been developed for its prevention, of which administration of fluids prior to subarachnoid block holds the importance. Gelatin is a colloidal plasma volume expander obtained from degraded gelatine. It is as effective as albumin solution in the treatment of spinal induced hypotension.
Aim: To compare the incidence and frequency of hypotension after subarachnoid block in patients receiving colloid (polymerised gelatin) or crystalloid (0.9% normal saline) as prehydration and compare side-effects of colloid and crystalloid prehydration.
Materials and Methods: A total of 60 patients scheduled for elective Transurethral Resection of Prostate (TURP) surgery were selected to participate in this prospective randomised double-blind study for a period of two years from April 2006 to April 2008. Patients were randomly allocated into two groups of 30 patients each. Group H received 500 mL of polymerised gelatine (Haemaccel) solution and group N received 1000 mL of 0.9% normal saline15 minutes prior to subarachnoid block. Intraoperative monitoring includes SBP, DBP, MAP and HR for 30 minutes. Incidence of hypotension and number of mephentermine boluses were noted. Statistical analysis of data was determined with Mann-Whitney U test and analysis of variance for repeated measures (ANOVA). Chi-square test was used to find out possible associations.
Result: After spinal anaesthesia mean systolic blood pressure decreased in both the groups and was lower in group N compared to group H (97±18.9 vs 102±9.26 mmHg). There was fall in diastolic blood pressure in both the groups and was maximum at 20th minute in group N and group H (66.37±5.47 vs 64.67±10.30). There was highly significant (p<0.01) fall in mean arterial pressure in group N. The change in the heart rate was highly significant (p<0.01) at different time interval in both the groups. Vasopressor was required in 90% and 60% patients in group N and group H, respectively. No statistical difference in the incidence of nausea and vomiting in both the groups.
Conclusion: The present study showed that preloading of fluids either with colloids or crystalloids prior to subarachnoid block reduces the incidence of hypotension but not completely eliminating it, also showed that colloids offset hypovolemia and hypotension more effectively than crystalloids in patients undergoing TURP surgery.