Semiquantitative 131 I MIBG Scintigraphy Predicts Intraoperative Blood Pressure Fluctuation in Patients Undergoing Surgery for Pheochromocytoma and Paraganglioma.

Objective: Severe blood pressure (BP) fluctuation happens during surgery for pheochromocytoma and paraganglioma (PPGL) due to the release of catecholamines. 131 I MIBG scintigraphy indicates the capacity of PPGL to retake and reserve catecholamines. This study aims to utilize 131 I MIBG scintigraphy to predict intraoperative BP fluctuation in patients undergoing PPGL surgery, thereby guiding preoperative preparation.

Methods: This study included 159 patients receiving 131 I MIBG scintigraphy before surgery for PPGL. Uptake of 131 I MIBG was assessed with an MIBG score ranging from 2 to 8. Factors that may be related to hemodynamic stability were collected. BP fluctuation was evaluated by systolic blood pressure average real variability (SBP ARV) and mean arterial pressure average real variability (MAP ARV).

Results: One hundred fifty-nine consecutive patients with PPGL were included in this study. Patients with an MIBG score of 2 (10.3±4.6 mm Hg) had lower SBP ARV than patients with a score of 5 (14.9±5.6 mm Hg, p =0.012), score of 7 (13.8±5.0 mm Hg, p =0.013) and score of 8 (14.7±7.3 mm Hg, p =0.007). Patients with 131 I MIBG score of 2 (7.6±3.2 mm Hg) also had a lower MAP ARV than patients with a score of 5 (10.3±4.3 mm Hg, p =0.045) and a score of 8 (9.8±4.5 mm Hg, p =0.029). In multiple linear regression analyses, MIBG score ( p =0.010), metanephrine ( p =0.014), and maximum preoperative blood pressure ( p =0.021) were correlated with SBP ARV.

Conclusions: Preoperative 131 I MIBG scintigraphy is associated with intraoperative BP fluctuation in patients with PPGL. Metanephrine, maximum preoperative blood pressure, and 131 I MIBG scintigraphy can predict intraoperative BP fluctuation independently. Personalized preoperative management can be offered to patients based on these assessments.