Cardiovascular effects of insufflation of the abdomen with carbon dioxide in standing horses sedated with detomidine.
OBJECTIVE
To determine the cardiovascular effects of 60 minutes of abdominal insufflation with CO2 to an intra-abdominal pressure of 15 mm Hg in standing horses receiving a constant rate infusion of detomidine.


METHODS
5 horses.


METHODS
Horses were randomly allocated into treatment or control groups. A washout period of a minimum of 7 days separated the 2 experimental periods of the crossover study. Catheters were placed into the right atrium, pulmonary artery, jugular vein, and right transverse facial artery after lidocaine infiltration. All horses were sedated with detomidine (8.54 microg/kg/h, i.v.). Horses in the treatment group received abdominal insufflation with CO2 via a laparoscopic cannula to a final and constant intra-abdominal pressure of 15 mm Hg for 60 minutes. Systemic arterial pressure, right atrial pressure, heart rate, cardiac output, core body temperature, and the pH and gas tensions of arterial and mixed venous blood were obtained. Cardiac index and systemic vascular resistance were calculated. Data were collected in 3 stages: preinsufflation (-10 and -5 minutes), insufflation (0, 15, 30, 45, and 60 minutes), and postinsufflation (70 and 80 minutes). The quality of sedation and level of analgesia were determined.


RESULTS
The PaO2 of horses in the treatment group was significantly higher after 60 minutes of pneumoperitoneum than in the control group. Core body temperature decreased significantly from baseline in both groups.


CONCLUSIONS
A 60-minute period of abdominal insufflation to an intra-abdominal pressure of 15 mm Hg did not induce significant cardiovascular abnormalities in healthy horses.
Cruz
Antonio M
AM
Veterinary Teaching Hospital, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Kerr
Carolyn L
CL
Bouré
Ludovic P
LP
Sears
William C
WC
D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure; D001831:Body Temperature; D002245:Carbon Dioxide; D002302:Cardiac Output / Q000502:physiology; D002404:Catheterization; D006339:Heart Rate; D006736:Horses / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects*; D014655:Vascular Resistance / Q000502:physiology
D002245:Carbon Dioxide