Elevated Perioperative Morbidity After Parathyroidectomy for Calciphylaxis Patients: A Nationwide Retrospective Observational Study.

Introduction: Calcific uremic arteriolopathy (CUA), also known as calciphylaxis, is a rare and potentially lethal condition associated with longstanding renal failure. It is defined by calcium and parathyroid hormone dysregulation, which leads to vascular calcification, painful skin necrosis, and high rates of sepsis-driven mortality. Although the mainstay treatment is medical therapy and supportive care, severe or recalcitrant cases will require parathyroidectomy, a modality associated with high perioperative complication rates of up to 40%. The aim of the study was to evaluate the association of CUA with surgical outcomes in a contemporary series of patients with secondary hyperparathyroidism (SHPT) using the American College of Surgeons National Surgical Quality Improvement Program patient registry.

Methods: A cross-sectional analysis of patients who underwent parathyroidectomy for SHPT with a diagnosis of CUA was identified using the National Surgical Quality Improvement Program participant use files from 2010 to 2021. Patients with SHPT and concomitant end stage renal disease who underwent parathyroidectomy served as a comparison group (non-CUA). Baseline characteristics, complications, and mortality rates were analyzed and compared using Chi-square and Mann-Whitney U tests. Multivariate analysis of risk factors associated with the complications was subsequently performed.

Results: A total of, 203 patients were included: 17 with CUA and 186 non-CUA. The CUA cohort were predominantly female (13/17 [77%] versus 94/186 [24%]). Preoperatively, patients with CUA were less likely to present at higher American Society of Anesthesiologists classes (12/17 [71%] in class III or IV versus 181/186 [97%]) and on dialysis (11/17 [65%] versus 163/186 [88%]). Reported rates of unplanned reintubation (2/17 [12%] versus 1/186 [0.5%], P = 0.019) and cardiac arrest (2/17 [12%] versus 1/186 [0.5%], P = 0.019) were higher in patients with CUA. Following logistic regression, CUA was identified as a risk factor for cardiac arrest (odds ratio 3.6 [95% confidence interval: 1.2, 6.7], P = 0.005). The rate of mortality between groups was comparable (1/17 [5.9%] versus 2/186 [1.1%], P = 0.232).

Conclusions: Surgical management of SHPT for patients with CUA was rare over an 11-year period. The CUA cohort appears to be at a lower preoperative risk compared to non-CUA patients, and perioperative mortality following parathyroidectomy appears to be lower than the prohibitive rates cited historically, although this may be a result of patient selection for surgical candidacy. Surgeons considering parathyroidectomy should be aware of the potentially elevated risk for postoperative cardiac or respiratory failure.