Abstract
BACKGROUND: Hypocalcemia is common after cervical procedures. Patients who have undergone Roux-en-Y gastric bypass (RYGB) experience increased risk for post-thyroidectomy hypocalcemia. This association has not been elucidated for nonbariatric operations that bypass the duodenum. METHODS: A multi-institutional retrospective cohort study included patients who underwent parathyroidectomy and/or thyroidectomy with prior sleeve gastrectomy (SG), bariatric RYGB, or nonbariatric gastrojejunostomy (GJ). The primary outcomes were early (≤6 months) and late (>6 months) postoperative hypocalcemia. The secondary outcomes were prolonged length of stay (>24 hours) and 30-day readmission. RESULTS: A total of 241 patients had prior SG (39%), RYGB (44%), or GJ (17%). Early (54%) and late (41%) hypocalcemia were common. Patients with prior GJ compared with SG had significantly higher rates of early hypocalcemia (64% vs. 44% p = 0.04). The rate of late hypocalcemia was higher in those with prior GJ (53%, p = 0.007) or RYGB (49%, p = 0.003) compared with SG (28%). By multivariable regression, early hypocalcemia was positively associated with parathyroid autotransplantation (odds ratio [OR] 6.36, p = 0.005), and more parathyroid glands removed (OR 1.45, p = 0.03), while higher preoperative calcium was associated with lower odds of hypocalcemia (OR 0.51, p = 0.02). Late hypocalcemia was independently associated with RYGB (OR 2.38, p = 0.01) and GJ (OR 3.1, p = 0.01). The highest rates of early (81%) and late (71%) hypocalcemia were among those with prior nonbariatric GJ who underwent total thyroidectomy. Early hypocalcemia was associated with prolonged length of stay and 30-day readmission. CONCLUSIONS: Patients with prior GJ or RYGB frequently experience hypocalcemia following cervical procedures, informing preoperative counseling and perioperative management. Preoperative calcium optimization is a potential mitigative strategy warranting further study.