title: Hypocalcemia induced during major and minor abdominal surgery in humans.
abstract: Hypocalcemia has only been rarely reported during surgical procedures not involving massive blood transfusions. The frequent observation in our hospital of a low serum ionized calcium level during surgery in nonacutely ill patients prompted us to investigate the calcium-PTH axis in three groups of subjects undergoing major (hepatectomy; n = 10), moderately severe, or minor surgery under general anesthesia (colectomy; n = 7, herniorrhaphy; n = 9) compared to that in one group of minor surgery cases under epidural anesthesia (herniorrhaphy; n = 15). Serum samples were obtained before anesthesia, after anesthesia but before surgery, and 40 and 120 min after the beginning of surgery in all groups of patients and for up to 3 days in major and moderately severe cases. Significant falls (P < 0.01), always proportional to the severity of the surgical/anesthesia procedure, were observed for ionized calcium (6-20%), total calcium (8-19%), and albumin (8-23%) accompanied by increases in intact PTH (105-635%). The decrease in ionized and total calcium correlated with a decrease in albumin (P < 0.001). Phosphorus, pH, and magnesium levels remained within the normal range. Adjustment of ionized calcium for variation in albumin revealed that 50-100% of the variation in ionized calcium could be attributed to a fall in albumin resulting from fluid administration to patients before admission to the surgery ward and between the onset of anesthesia and the end of surgery (1.2-5.6 L). Albumin- and pH-independent residual ionized calcium decreases of 12.2% in the hepatectomy group, 4.6% in the group of moderately severe and minor cases under general anesthesia, and 3.7% in the control group reflected the severity of the surgical/anesthesia procedure.
authors.affiliation: Department of Biochemistry, Centre Hospitalier de l'Université de Montréal, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Lepage
authors.forename: G
authors.initials: G
authors.lastname: Légaré
authors.forename: C
authors.initials: C
authors.lastname: Racicot
authors.forename: J H
authors.initials: JH
authors.lastname: Brossard
authors.forename: R
authors.initials: R
authors.lastname: Lapointe
authors.forename: M
authors.initials: M
authors.lastname: Dagenais
authors.forename: P
authors.initials: P
authors.lastname: D'Amour
mesh_terms: D000005:Abdomen / Q000601:surgery; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006996:Hypocalcemia / Q000209:etiology*; D017674:Hypophosphatemia / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D012709:Serum Albumin / Q000032:analysis; D013514:Surgical Procedures, Operative
chemical_list: D010281:Parathyroid Hormone; D012709:Serum Albumin