Changes in arterial partial pressure and end-expired pressure of carbon dioxide in prepubescent and adult bitches undergoing ovariohysterectomy by videolaparoscopy or conventional laparotomy

Abstract

This paper aimed to determine arterial partial pressure of carbon dioxide (PaCO2), end-expired CO2 pressure (ETCO2), and the difference between arterial and end-expired CO2 pressure (Pa - ETCO2) in prepubescent and adult bitches undergoing videolaparoscopic or conventional ovariohyterectomy (OH). Forty bitches were randomly assigned to four groups: Conventional Adult (CA), Conventional Pediatric (CP), Videolaparoscopic Adult (VA) and Videolaparoscopic Pediatric (VP). Pulse rate (PR), respiratory rate (RR), systolic, mean, and diastolic arterial pressures (SAP, MAP, DAP), ETCO2, peak inspiratory pressure (PIP), pH, arterial partial pressure of oxygen (PaO2), PaCO2, base excess (BE) and HCO3 - were measured. Based on the PaCO2 and ETCO2 values, Pa-ETCO2 was determined. There was no significant difference in PaCO2 between the VA (42.5±5.2 to 53.7±5.2) and VP (48.4±5.4 to55.4±5.7) groups. During the postoperative period, all groups presented with hypertension. However, mild hypertension (SAP 150 to 159mmHg) was observed in the VP group as compared to severe hypertension (SAP>180mmHg) in the CA group, suggesting that both the age range and videolaparoscopic OH are associated with lower levels of hypertension during the postoperative period in dogs.