BACKGROUND: Sugammadex and neostigmine are routinely used to reverse residual neuromuscular blocks at the end of surgery. Sugammadex has been linked with prolongation of laboratory coagulation markers, but clinical relevance on postoperative blood loss and transfusions remains unclear. METHODS: In this retrospective, single-center, cohort study, we analyzed medical records of adult patients having noncardiac surgery who were given sugammadex or neostigmine from May 2016 to December 2020. Our primary outcome was the incidence of any postoperative transfusion of red blood cells, and/or fresh-frozen plasma, and/or platelets. Secondary outcomes were duration of hospitalization, need for resurgery, and postoperative intensive care unit (ICU) admission. After propensity score weighting, the odds ratio (OR) for postoperative transfusion was assessed in both groups (sugammadex versus neostigmine) using a generalized estimation equation to count within-subject correlation weighted by the inverse propensity score. RESULTS: Out of 39,325 eligible surgeries, 33,903 surgeries in 29,062 patients were included in the analysis; with 4581 patients receiving sugammadex and 29,322 patients receiving neostigmine. The raw incidence of postoperative transfusion was 7.40% in sugammadex and 7.45% in the neostigmine group. After weighting by propensity score, the incidence of postoperative transfusion was 8.01% in the sugammadex and 7.38% in the neostigmine group (OR, 1.11 [95% confidence interval [CI], 0.97-1.26; P = .118]). There was no difference in duration of hospitalization and need for resurgery, but odds of postoperative ICU admission were significantly higher for patients receiving sugammadex than those receiving neostigmine (OR, 1.33 [98.33% CI, 1.17-1.52; P < .0001]). Our a priori planned analysis of coagulation laboratory parameters could not be completed because of a high amount of missing laboratory data. CONCLUSIONS: There is no statistically significant nor clinically important difference in the risk of postoperative transfusion in patients receiving sugammadex or neostigmine. (Anesth Analg 2023;136:745-52) KEY POINTSSummary statistics (presented as % of patients, mean ± SD, or median [Q1-Q3], respectively, for factors, symmetric continuous variables, and skewed continuous variables; Duration of surgery was summarized by median [10th, 90th percentiles]). Abbreviations: ASA, American Society of Anesthesiologists; ASD, absolute standardized difference; BMI, body mass index; IPTW, inverse probability of treatment weighting. a ASD is the absolute difference in means or proportions divided by the pooled standard deviation before or after weighting each observation with IPTW. Any covariate with an ASD >0.10 was considered to be imbalanced and would be adjusted for in the analysis.

Background: PTHrP-secreting pancreatic neuroendocrine tumors (PNET) are a recognized cause of malignancy associated hypercalcemia. Herein, we report a case of severe hypercalcemia due to an extreme elevation of PTHrP from a PNET, where after treatment of the hypercalcemia, symptomatic hypocalcemia occurred. Clinical Case: A 59 year-old-woman with a recurrent PNET with liver metastases undergoing an evaluation for multi-visceral transplant presented with acute confusion, nausea and vomiting. Diagnostic testing identified an extreme elevation of total calcium (Ca) [&gt;20.1 mg/dL (8.5 - 10.2)] from two different samples [serum albumin 4.1 g/dL (3.9 - 4.9)]. The total Ca level one month earlier was 8.3 mg/dL with a serum albumin of 3.1 g/dL. Total Ca measurements were performed with the Ca Gen.2 assay on a cobas c702 chemistry analyzer (Roche Diagnostics). Results greater than the analytical measurement range (0.8 – 20.1 mg/dL) were diluted with saline and confirmed (22.6 mg/dL). A Radiometer ABL 800 Flex blood gas analyzer was used to determine the ionized Ca concentration [2.94 mmol/L (1.08 - 1.30)]. Upon presentation the serum creatinine (Cr) was 2.07 mg/dL (0.58 - 0.96); eGFR utilizing the MDRD equation 24 mL/min/1.73m2; baseline serum Cr 0.78 mg/dL. Her serum 25-OH vitamin D was 31 ng/mL (31.0 - 80.0), PTH 12 pg/mL (15 - 65), phosphate 4.3 mg/dL (2.7 - 4.8) and 1, 25-OH vitamin D 39.1 (15.0 - 60.0). PTHrP measurements were performed by ARUP Laboratories via liquid chromatography tandem mass spectrometry (LC-MS/MS) and resulted in a reported value of &gt;2500 pmol/L (0.0 - 3.4). Her symptoms resolved and the corrected Ca gradually decreased to 8 mg/dL after treatment with IV fluids, calcitonin 200 units sc every 12 hours for 48 hours, 60 mg IV pamidronate, and five sessions of hemodialysis. Within thirteen days of receiving pamidronate, her corrected Ca slowly increased to 12mg/dL; thus, she received a single dose of 120 mg sc denosumab. Nine days later, the patient developed symptomatic hypocalcemia (7.3 mg/dL) manifested by paresthesia in the hands and feet and perioral numbness. She then received multiple doses of oral and intravenous Ca along with 50,000 units of oral ergocalciferol twice weekly. The corrected Ca normalized (8.1 mg/dL) and symptoms resolved. The patient was discharged with plans for future treatment of her underlying malignancy. Conclusion: This is the first report of a PNET producing an extreme elevation of PTHrP of higher than 2500 pmol/L, resulting in a concordant extreme elevation of total calcium within a month of documented normocalcemia. Treatment of hypercalcemia with denosumab may result in the development of hypocalcemia requiring treatment.