The Effect on Serum Electrolytes in Patients Undergoing Elective Craniotomy for Supratentorial Brain Tumors Using PlasmaLyte A and Normal Saline as Intravenous Replacement Fluid.

Background and aim The type of fluid which is administered to patients is very crucial and important. In this study normal saline is compared with PlasmaLyte A in patients undergoing craniotomy for supratentorial brain tumors. Generally normal saline is used in neurosurgical patients; it is seen to be associated with hyperchloremic acidosis. A balanced crystalloid, e.g. PlasmaLyte A, maintains a better metabolic status than normal saline. This study was planned to study the metabolic effects of using PlasmaLyte A as compared with normal saline as intravenous fluids in patients undergoing supratentorial brain tumour surgeries. Methods This is a prospective, randomized, double-blinded study in patients undergoing craniotomy for supratentorial brain tumors. Written informed consent was taken from patients and they were divided into two groups, Group A and B of 40 patients each by computer-generated random numbers. Group A received PlasmaLyte A and Group B received normal saline intra-operatively as maintenance fluid. Heart rate, mean arterial pressure, total fluid administered, serum sodium, serum potassium, chloride, lactate, pH, serum urea, serum creatinine, osmolarity, and urine output were assessed at different time intervals in both groups. Blood urea and creatinine were assessed to see acute kidney injury. Results There was no difference in mean values of serum sodium, potassium, lactate, serum urea, creatinine and serum osmolarity in both groups throughout the study period. However there was a rise in serum chloride and a low pH was noted in Group B. The urine output was also similar in both groups. The metabolic status of patients receiving PlasmaLyte was better than those receiving normal saline. Conclusion Normal saline may cause hyperchloremic metabolic acidosis which may be avoided by using balanced crystalloids. The use of balanced crystalloids should be preferred to normal saline in neurosurgical patients to ensure a better metabolic status and good clinical outcome.