A Comparative study on Efficacy of 10% and 20% Mannitol for Inducing Diuresis During Renal Transplant Surgery

Objective: Mannitol is one of the most commonly used osmotic diuretics during renal transplant surgery. Two concentrations of mannitol, 10% and 20%, are available, however there is no consensus about which concentration is to be preferred. The purpose of this study was to compare between the efficacy of the two concentrations of mannitol for inducing diuresis during renal transplant surgery and the need for further diuretics (furosemide). Methods: A prospective study was carried out on 60 patients of either sex undergoing living donor renal transplantation in Zheen International Hospital between April 2011 and May 2015 for the end-stage renal failure. Patients were assigned into two groups, group 1 received 10% mannitol and group 2 received 20% mannitol. All patients evaluated preoperatively by the anesthetist, immunosuppression was initiated the day before the surgery using combination of immunosuppressant drugs. General anesthesia induced with thiopentone and maintained with atracurium and isoflurane, vital parameters monitored, the donated kidney was placed retroperitoneally in the iliac fossa and anastomosis between renal and iliac vessels were established. Normal saline 0.9% used as intravenous fluid, once venous anastomosis started diuresis initiated with mannitol 10% or 20% (2-3 ml/kg). The urine output of the patients was monitored and furosemide was given as needed with the aim of at least 2 ml/kg/hr of urine output. Results: The demographic characteristics between both study groups were comparable (p > 0.05). Patients treated with 10% mannitol (group 1) were found to require significantly less overall dose of mannitol as compared to patients received 20% mannitol (group 2) (p < 0.0001). Additionally, group 1 required significantly lower additional doses of furosemide as compared to group 2 (p < 0.0474). The duration of surgery, fluid requirement and urine output were comparable between both study groups (p > 0.05). Conclusion: A lower dose of mannitol using lower concentration (10%) is more effective in terms of need of overall dose in grams for inducing diuresis with less need for furosemide compared to higher concentration (20%) of mannitol.