Propofol-Associated Urine Discoloration: Systematic Literature Review

Introduction: Propofol occasionally induces a green or pink-cloudy urine discoloration. A lesser-known effect is green discoloration of hair, milk, liver, or stool. We aimed to gain insight into the features of these disturbances. Methods: The terms (“propofol” OR “fospropofol”) AND (“green” OR “pink” OR “cloudy” OR “pink-cloudy”) were searched in Excerpta Medica, MEDLINE/PubMed®, and Web of Sciences databases, with no language limit, from inception up to February 2023 (CRD4202236804). Articles reporting individually documented cases were retained, and data were extracted using a checklist. Results: Seventy-seven original reports documented 95 cases (including 13 subjects ≤18 years of age). Completeness of reporting was satisfactory in 33, good in 35, and excellent in 27 cases. Propofol-associated green urine discoloration was observed in 54 patients. In most instances (n = 21, 39%), propofol was given for ≥24 h. Sometimes, however, the urine discoloration developed after propofol for ≤3 h (n = 12, 22%). Propofol-associated urine discoloration was usually observed during the administration of this agent, but it was at times (n = 11) first recognized ≥3 h after propofol discontinuation. The duration of green urine discoloration was usually ≤24 h after stopping propofol. Propofol-associated green urine discoloration was never associated with worsening kidney function. A pink-cloudy urine discoloration was observed in 32 subjects with an acidic urine pH and increased uric acid excretion given propofol for ≤24 h. A stage I acute kidney injury was observed in 2 cases (6.3%) of propofol-associated pink-cloudy urine discoloration. Nine cases of non-urinary green discoloration were observed: hair (n = 4), breast milk (n = 1), liver (n = 1), stool (n = 1). Conclusion: Propofol is sometimes associated with a green (benign) or pink-cloudy (occasionally associated with mild acute kidney injury) urine discoloration. Rarely, non-urinary green discoloration has been reported.