Intraoperative hypotension is associated with increased postoperative complications in patients undergoing surgery for pheochromocytoma-paraganglioma: a retrospective cohort study

BACKGROUND: Dramatic hemodynamic fluctuation occurs frequently during surgery for pheochromocytoma or paraganglioma. However, the criteria of intraoperative hemodynamic instability vary widely, and most of them were defined arbitrarily but not according to patients’ prognosis. The objective was to analyze the relationship between different thresholds and durations of intraoperative hyper−/hypotension and the risk of postoperative complications in patients undergoing surgery for pheochromocytoma or paraganglioma. METHODS: This was a retrospective single-center cohort study performed in a tertiary care hospital from January 1, 2005 to December 31, 2017. Three hundred twenty-seven patients who underwent surgery for pheochromocytoma or paraganglioma, of which the diagnoses were confirmed by postoperative pathologic examination, were enrolled. Those who were less than 18 years, underwent surgery involving non-tumor organs, or had incomplete data were excluded. The primary endpoint was a composite of the occurrence of AKI or other complications during hospital stay after surgery. Multivariate Logistic regression models were used to analyze the association between different thresholds and durations of intraoperative hyper−/hypotension and the development of postoperative complications. RESULTS: Forty three (13.1%) patients developed complications during hospital stay after surgery. After adjusting for confounding factors, intraoperative hypotension, defined as systolic blood pressure (SBP) of ≤95 mmHg for ≥20 min (OR 3.211; 99% CI 1.081–9.536; P = 0.006), SBP of ≤90 mmHg for ≥20 min (OR 3.680; 98.8% CI 1.107–12.240; P = 0.006), SBP of ≤85 mmHg for ≥10 min (OR 3.975; 98.3% CI 1.321–11.961; P = 0.003), and SBP of ≤80 mmHg for ≥1 min (OR 3.465; 95% CI 1.484–8.093; P = 0.004), were associated with an increased risk of postoperative complications. On the other hand, intraoperative hypertension was not significantly associated with the development of postoperative complications. CONCLUSIONS: For patients undergoing surgery for pheochromocytoma or paraganglioma, intraoperative hypotension is associated with increased postoperative complications; and the harmful effects are level- and duration-dependent. The effects of intraoperative hypertension need to be studied further.