Incidence and determinants of acute kidney injury following Mannitol therapy

Abstract

Background: Mannitol is a commonly used drug in general medicine and neuro medicine wards. Mannitol reduces intracerebral pressure by redistributing water from the brain parenchyma. Renal failure is cited as one of the most common side effects and concern over this often limits the use of Mannitol. This study is intended to find out whether the use of Mannitol, in the doses commonly used in our setting, is associated with derangement of renal function and if so what are its determinants. Materials and Methods: We did a prospective observational study on 151 consecutive patients. The duration of the study was for one year from January to December 2020. Mannitol was used in the usual dose of 100 ml of 20% solution 8 hourly. Acute kidney injury was diagnosed based on the KDIGO criteria. Results: The study population included 103 males (68%) and 48 females (32%). The age group ranged from 14 years to 98 years. A total of 42 patients (27.8%) developed acute kidney injury of which 26 were males (62%) and 16 were females (38%). By multiple regression analysis, age more than 65 years and diastolic blood pressure more than 100 mm of Hg were the two significant predictors for the occurrence of acute kidney injury. Conclusion: Mannitol is a safe drug that can be used to reduce intracerebral pressure, provided the dose of the drug is carefully monitored, especially in those with risk factors such as advanced age and high diastolic blood pressure. An equally important aspect is the early recognition of the renal impairment because stopping the drug will in most situations reverse the damage. Since any renal impairment, however small and short-lasting, can have adverse long-term effects, such insults must be avoided as far as possible.

Keywords

• acute kidney injury
• cerebral edema
• mannitol