독수리(Aegypius monachus)의 흡입마취에서 Capnography를 이용한 호기말 이산화탄소분압 모니터링

Capnographic Monitoring of End-Tidal Partial Pressure of Carbon Dioxide in Anesthetized Cinereous vultures (Aegypius monachus)

The relationships between end-tidal partial pressure of carbon dioxide ($P_{ET}CO_2$) and arterial partial pressure of carbon dioxide ($P_aCO_2$), and between $P_{ET}CO_2$ and blood pH in isoflurane-anesthetized cinereous vultures were evaluated. Nine cinereous vultures (weighing 7.3-9.5 kg) were anesthetized via mask with isoflurane, intubated, and connected to a mechanical ventilator. By mechanical ventilator, respiratory rate was altered to achieve a $P_{ET}CO_2$ randomly selected among 30 to 35 mmHg. $P_aCO_2$ and blood pH were determined in serial arterial samples and compared with concurrent $P_{ET}CO_2$ measured with a sidestream capnography. Thirty six samples, nine cinereous vultures were tested 4 times each, were used to determine correlations coefficients between $P_aCO_2$ and $P_{ET}CO_2$, and between $P_{ET}CO_2$ and blood pH. Strong correlations were observed between $P_aCO_2$ and $P_{ET}CO_2$ (r = 0.951, P = 0.000, y = 1.679x - 30.236, $R^2=0.905$) as well as between $P_{ET}CO_2$ and blood pH (r = -0.728, P = 0.000, y = -0.024x + 8.389, $R^2=0.530$) with Pearson's correlation coefficient and simple linear regression. These results suggest that the capnography used provided a sufficiently accurate estimation of $P_aCO_2$ and blood pH. Thus, the monitoring of $P_{ET}CO_2$ can be useful method to prevent hypoventilation for cinereous vultures receiving mechanical ventilation.