10040- STMO-2 ASSOCIATED FACTORS LEADING TO INTRAOPERATIVE HYPOTENSION DUE TO THE USE OF 5-AMINOLEVLINIC ACID

Abstract INTRODUCTION Photodynamic diagnosis using 5-aminolevulinic acid (5ALA) for gliomas has contributed to improved resection rates and extended progression free survival and is widely used in Japan. However, there have been multiple reports of marked hypotension during anesthesia induction after 5ALA administration, leading to its listing as a significant adverse effect from April 2020. In this study, we retrospectively analyzed factors contributing to intraoperative hypotension (IOH) caused by 5ALA use. MATERIALS AND METHODS We included 148 cases of glioma that underwent surgery at our hospital from 2015 to 2024. The cases were stratified into the 5ALA administration group and the non-administration group. IOH was defined as a mean arterial pressure below 60 mmHg after anesthesia induction. We compared the incidence of IOH between the two groups and evaluated potential risk factors such as age, body weight, and preoperative antihypertensive medication use using the Chi-square test. RESULTS The 5ALA group included 72 cases (48.6%), while the non-5ALA group included 76 cases (51.4%). There was no significant difference in the incidence of IOH between the groups (p=0.296). In the elderly group (>60 years), the incidence of IOH was significantly higher in the 5ALA group (p=0.029). For patients weighing <75 kg, the 5ALA group had a significantly higher incidence of IOH (p=0.039), whereas for those weighing >76 kg, the non-5ALA group had a higher incidence (p=0.049). Additionally, in patients taking calcium channel blockers (CCBs) or angiotensin receptor blockers (ARBs), or both, the incidence of IOH was significantly higher with 5ALA administration (p=0.033, 0.015, 0.023, respectively). CONCLUSION Elderly patients, those weighing &lt:75 kg, and those taking CCBs/ARBs are at a higher risk of IOH, suggesting the need for careful blood pressure management during and after surgery in these populations.