Cloudy Urine after Propofol Anesthesia; A Rare Occurrence after a Routine Anesthetic

Abstract

A 27-year old man with a history of achalasia presented for an elective laparoscopic pylorotomy under general anesthesia. He was well with no significant comorbidities nor risk factors for hyperuricemia. The patient underwent routine preoperative screening and preparation. He was intubated and a urinary catheter was inserted prior to the start of surgery. A total intravenous anesthesia technique with neuromuscular blockade was used. Propofol and remifentanil were infused to maintain anesthesia. After completion of the surgical procedure, anesthesia was stopped with cessation of the respective infusions and reversal of neuromuscular blockade. It was then observed that there was cloudy urine in the urinary bag. A sample of the urine was sent for further analysis and uric acid crystals were visualized under microscopy, causing the urine to take on a cloudy white appearance. The patient continued to be monitored in the post-operative care unit where the urine returned to being clear after an hour. The patient was followed up to the point of discharge. He was able to micturate normally and produced clear urine. Subsequent postoperative urinalysis did not show the presence of uric acid crystals. Figure 1: Clear urine emptied out into bottle before the start of the operation. Cloudy urine in urinary bag occurring after propofol anesthesia.

Propofol-Associated Urine Discoloration: Systematic Literature Review

“…Sixty-seven articles were published in English, six in Spanish, two in Dutch, one in Korean, and one in Turkish. The mentioned publications documented 95 cases of propofol-associated discoloration (and no case of fospropofol-associated discoloration): 54 (57%) with a green urine discoloration [2,, 32 (34%) with a pink-cloudy urine discoloration [3,[60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77][78], and nine (9.5%) with a non-urinary green discoloration [46,[79][80][81][82][83][84][85][86]. Completeness of reporting was satisfactory in 33 (35%), good in 35 (37%), and excellent in 27 (28%) cases.…”

“…A pink-cloudy urine discoloration was reported in 32 cases with a median age of 27 years [3,[60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77][78]]. An excessive body weight, an acidic urine pH, and increased uric acid excretion were documented in many cases (Table 3).…”