title: Hyperkalemia in neonatal diarrheic calves depends on the degree of dehydration and the cause of the metabolic acidosis but does not require the presence of acidemia.
abstract: Hyperkalemia is a clinically important electrolyte imbalance in neonatal diarrheic calves that has previously been associated with skeletal muscle weakness and life-threatening cardiac arrhythmias. The aim of the present retrospective analysis was to identify risk factors for hyperkalemia in a convenience sample of 832 calves (≤ 21 d of age) with a clinical diagnosis of diarrhea admitted to a veterinary teaching hospital. Plasma potassium concentrations were most closely associated with parameters of dehydration and renal function such as serum creatinine [Spearman correlation (rs) = 0.61], urea (rs = 0.51), and inorganic phosphorus concentrations (rs = 0.64). Plasma potassium concentrations were weakly associated with venous blood pH (rs = -0.21). Although venous blood pH was not predictive in a multivariate linear regression analysis, the odds of having hyperkalemia (>5.8 mmol/L) in acidemic calves was found to be 8.6 times as high as in nonacidemic calves [95% confidence interval (CI): 4.8-15.4]. However, the presence of hyperkalemia depended on the nature of an existing acidosis, and the odds for the presence of hyperkalemia in acidemic calves with hyper-D-lactatemia (>3.96 mmol/L) were only 0.15 times as high as in acidemic calves with normal D-lactate concentrations (95% CI, 0.11-0.22). Acidemia in hyperkalemic diarrheic calves was associated with hyponatremia and increased concentrations of inorganic phosphorus, L-lactate, and unidentified strong anions that presumably included uremic anions such as sulfate. We conclude that hyper-D-lactatemia in neonatal diarrheic calves is not usually associated with elevated plasma potassium concentrations. Application of the simplified strong ion acid-base model indicated that dehydration is an important contributor to the pathogenesis of hyperkalemia and acidemia in neonatal calves with diarrhea.
authors.affiliation: Clinic for Ruminants with Ambulatory and Herd Health Services at the Centre for Clinical Veterinary Medicine, LMU Munich, Sonnenstraße 16, 85764 Oberschleißheim, Germany. Electronic address: Florian.Trefz@campus.lmu.de.
authors.forename: F M
authors.initials: FM
authors.lastname: Trefz
authors.affiliation: College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.
authors.forename: P D
authors.initials: PD
authors.lastname: Constable
authors.affiliation: Clinic for Ruminants with Ambulatory and Herd Health Services at the Centre for Clinical Veterinary Medicine, LMU Munich, Sonnenstraße 16, 85764 Oberschleißheim, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Sauter-Louis
authors.affiliation: Clinic for Ruminants with Ambulatory and Herd Health Services at the Centre for Clinical Veterinary Medicine, LMU Munich, Sonnenstraße 16, 85764 Oberschleißheim, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Lorch
authors.affiliation: Clinic for Ruminants with Ambulatory and Herd Health Services at the Centre for Clinical Veterinary Medicine, LMU Munich, Sonnenstraße 16, 85764 Oberschleißheim, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Knubben-Schweizer
authors.affiliation: UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: I
authors.initials: I
authors.lastname: Lorenz
mesh_terms: D000138:Acidosis / Q000662:veterinary; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology*; D003404:Creatinine / Q000097:blood; D003681:Dehydration / Q000503:physiopathology*; D003967:Diarrhea / Q000150:complications / Q000503:physiopathology / Q000662:veterinary*; D006863:Hydrogen-Ion Concentration; D006947:Hyperkalemia / Q000209:etiology / Q000378:metabolism / Q000662:veterinary*; D019344:Lactic Acid / Q000097:blood / Q000378:metabolism; D016014:Linear Models; D016017:Odds Ratio; D011188:Potassium / Q000097:blood; D012189:Retrospective Studies
chemical_list: D019344:Lactic Acid; D003404:Creatinine; D011188:Potassium
keywords: d-lactate; inorganic phosphorus; potassium; strong ion approach