postoperative acute kidney injury in patients undergoing prolonged neurosurgical operations

Conditions: Postoperative Acute Kidney Injury

Summary: postoperative acute kidney injury in patients undergoing prolonged neurosurgical operations

* postoperative acute kidney injury (aki) is a highly prevalent and prognostically important complication in various surgical settings. patients who developed postoperative aki is independently associated with markedly increased morbidity, mortality1-8 and higher economic burden1. * aki was defined by an increase in serum creatinine (scr) ≥ 0.3 mg/dl or by an increase in scr ≥ 50% and/or by a decrease in urine output to 0.5 ml/kg/hour for 6 hours, in the first 48 hours after surgery. * patients who developed aki had a higher total icu costs, prolonged length of hospital and icu stay, and longer duration of postoperative mechanical ventilation. * aki has been studied in different surgical procedures especially cardiac \& abdominal surgeries. * kovacheva et al 2016 retrospective study included 1656 craniotomy patients from 1998 to 2011. the aki used criteria was rifle (risk, injury, failure, loss of kidney function and end-stage renal failure), they reported an incidence of 9.9% of postoperative aki9. * deng et al 2017 also reported an incidence of aki up to 13.5% in patients undergoing neurosurgical surgery within the first 7 days. it was associated with independent risk factors included intraoperative blood loss, postoperative reoperation, use of mannitol during operation, concentration of cystatin-c; a biomarker protein detecting early kidney injury before creatinine changes and postoperative apache ii score10. * as the number of neurosurgical procedures has been increased worldwide and in our department as well with new types of prolonged neurosurgery e.g. skull - base - major cerebrovascular beside major cranial tumor excision. it becomes a necessary to re-evaluate the incidence, factors behind aki and outcome in such prolonged surgery. * in 2002, the acute dialysis quality initiative (adqi) was created with primary goal was to create a uniform, accepted definition of aki; hence rifle criteria was born. rifle is an acronym of risk, injury, failure, loss of kidney function \& end-stage kidney failure. * in 2004, the acute kidney injury network (akin) was formed. a report of the akin proposed the following criteria for aki. * the akin criteria differ from the rifle criteria in several ways. the rifle criteria are defined as changes within 7 days, while the akin criteria suggest using 48 hours. the akin classification includes less severe injury in the criteria and akin also avoids using the glomerular filtration rate as a marker in aki, as there is no dependable way to measure glomerular filtration rate and estimated glomerular filtration rate are unreliable in aki. * haase et al. 2009 in their comparative study between rifle and akin in cardiac surgery; found no difference between the aki scores11.

Eligibility criteria:
inclusion criteria: * patients aged 18 years or older who will do prolonged neurosurgical procedure, duration of surgery more than 4 hours and asa 1-2-3. exclusion criteria: * refusal of consent, preexisting renal transplantation, preexisting nephrectomy, presence of aki before neurosurgical procedure, operation less than 4 hours, patients aged under 18 years, pregnancy and asa 4-5.