PetCaseFinder

Peer-reviewed veterinary case report

Severe hypercarbia resulting from inspiratory valve malfunction in two anesthetized horses.

Journal:
Journal of the American Veterinary Medical Association
Year:
1991
Authors:
Baxter, G M et al.
Affiliation:
Department of Large Animal Medicine · United States
Species:
horse

Plain-English summary

In two adult horses that were under anesthesia for surgery, a serious condition called severe hypercarbia (which means they had too much carbon dioxide in their blood) was discovered through blood tests. Even though the horses seemed to be properly anesthetized, they were still trying to breathe on their own against the ventilator. It turned out that a valve in the anesthesia machine was stuck open, allowing carbon dioxide that should have been expelled to be inhaled again. Once the valve was fixed, the horses' condition improved. This situation highlights the importance of checking the anesthesia machine if an anesthetized horse is having trouble breathing and shows signs of high carbon dioxide levels.

Abstract

Severe hypercarbia was documented by arterial blood gas analysis in 2 adult horses anesthetized for exploratory laparotomy. Both horses appeared to be adequately anesthetized, but continued to breathe against the ventilator. In both cases, the inspiratory valve on the anesthesia machine was found to be stuck open, permitting expired CO2 to return to the inspiratory limb of the anesthetic circuit and to be inhaled with the next breath. Correction of the malfunctioning valve alleviated the hypercarbia. Problems with the flow valves of the anesthesia machine should be suspected when anesthetized horses breathe against the ventilator and develop severe hypercarbia.

Find similar cases for your pet

PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.

Search related cases →

Original publication: https://pubmed.ncbi.nlm.nih.gov/1995568/