Acute Kidney Injury Manifesting as Postoperative Respiratory Failure after Transforaminal Lumbar Interbody Fusion Surgery: A Case Report

Abstract Perioperative acute kidney injury is known to carry significant morbidity and mortality, yet it is a disease that is poorly recognized and misdiagnosed. Here, we present a case of a middle-aged female, a known case of Type 2 diabetes mellitus and recently diagnosed hypertension. She underwent transforaminal lumbar interbody fusion under general anesthesia. The intraoperative blood loss volume was around 1700 mL. There was no requirement for inotropes or vasopressors intraoperatively. A decrease in the urine output was noted, with a total urine output of 200 mL in the intraoperative period. The patient was extubated after the surgery and was maintaining stable vitals. However, 1 hour after the surgery, the patient became drowsy and hypotensive, and a fall in oxygen saturation was noted. Arterial blood gas at that time was suggestive of combined respiratory and metabolic acidosis. The patient was immediately intubated, resuscitated, and shifted to the critical care unit. Our patient developed acute kidney injury (AKI) following the surgery owing to massive intraoperative blood loss and multiple transfusions. Consequent metabolic acidosis resulted in a compensatory increase in the respiratory drive. However, due to respiratory muscle fatigue, the residual effect of anesthetic administration and postoperative pain, the acidosis gradually worsened. The patient developed drowsiness and presented with type II respiratory failure in the immediate postoperative period. So the patient was shifted to the critical care unit, and hemodialysis was immediately instituted. A high index of suspicion and early intervention were necessary for early diagnosis and timely management in our patient.