Risk factors and management of hypotension and nausea during 5-aminolevulinic acid-assisted transurethral resection of bladder tumors under spinal anesthesia

OBJECTIVE: This study aimed to evaluate intraoperative adverse events in patients undergoing photodynamic diagnosis (PDD)-assisted transurethral resection of bladder tumor (TURBT) using oral 5-aminolevulinic acid (5-ALA) (ALA-PDD-TURBT) under spinal anesthesia. METHODS: This single-center retrospective study included 109 patients who underwent ALA-PDD-TURBT under spinal anesthesia between January 2019 and April 2023. Hypotension was defined as a systolic blood pressure ≤ 80 mmHg. We evaluated the incidence of any adverse events and investigated the risk factors for hypotension, nausea, and vomiting. RESULTS: Hypotension was observed in 64 patients (58.7 %), while nausea and vomiting were observed in 29 patients (26.6 %). No adverse events of Clavien-Dindo grade ≥ 3 were observed. No significant association was found between hypotension and various patient-related factors, including age, sex, smoking history, comorbidities, presence of hypertension, use of antihypertensive agents, continuation of antihypertensive medication on the day of surgery, and administration of α-blockers for benign prostatic hyperplasia on examination. Regarding nausea and vomiting, the use of phenylephrine was identified as a significant risk factor (odds ratio, 10.2; 95 % confidence interval, 1.92-53.90; P < 0.01). CONCLUSIONS: Our findings suggest that ALA-PDD-TURBT is a safe procedure with a low risk of severe complications. Although hypotension, nausea, and vomiting were relatively common, they were generally manageable with pharmacological interventions. No strong predictive risk factors for hypotension were identified; however, the use of phenylephrine was associated with an increased risk of nausea and vomiting.