Effects of general anesthesia on plasma colloid oncotic pressure in dogs.
OBJECTIVE
To determine the magnitude of the change in colloid oncotic pressure (COP) associated with general anesthesia in dogs undergoing a variety of elective procedures.


METHODS
Cohort study.


METHODS
50 client-owned dogs.


METHODS
For each dog, preanesthetic and postanesthetic PCV, plasma total solids (TS) concentration, and COP were determined. The procedures requiring anesthesia, volume of crystalloid fluids administered IV, duration of anesthesia, age, weight, and sex were recorded.


RESULTS
Postanesthetic PCV (mean +/- SD, 41.8 +/- 5.4%), TS concentration (6.3 +/- 0.8 g/dL), and COP (19.4 +/- 3.6 mm Hg) were significantly decreased, compared with preanesthetic values (48.8 +/- 5.9%, 7.2 +/- 0.7 g/dL, and 24.4 +/- 4.2 mm Hg, respectively). None of the variables tested could be used to reliably predict changes in COP.


CONCLUSIONS
Results suggested that COP in healthy dogs may decrease by 5 mm Hg on average after general anesthesia and that this decrease may not be reliably predicted by the volume of fluids administered IV during anesthesia or by the concurrent measured decrease in TS concentration.
Dismukes
David I
DI
Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
Thomovsky
Elizabeth J
EJ
Mann
F A
FA
Middleton
John R
JR
D000768:Anesthesia, General / Q000662:veterinary*; D018685:Anesthetics, Inhalation / Q000494:pharmacology; D018686:Anesthetics, Intravenous / Q000494:pharmacology; D000818:Animals; D001798:Blood Proteins / Q000502:physiology*; D003102:Colloids / Q000378:metabolism*; D000077324:Crystalloid Solutions; D004285:Dogs; D007552:Isotonic Solutions / Q000008:administration & dosage / Q000494:pharmacology; D009997:Osmotic Pressure / Q000502:physiology*; D015532:Rehydration Solutions / Q000008:administration & dosage / Q000494:pharmacology
D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D001798:Blood Proteins; D003102:Colloids; D000077324:Crystalloid Solutions; D007552:Isotonic Solutions; D015532:Rehydration Solutions