A Comparative Study of The Effects of Norepinephrine , Isoproterenol & Nitroglycerin on The Hemodynamic and Blood Gas Analysis Changes in Air Embolized Cats

Lee, Il Ok; Han, Sung Min; Suh, Byung Te

Abstract

The effects of Norepinephrine(NE), Isoproterenol(ISO) and Nitroglycerin(NTG) on the hemodynamic, arterial and venous blood gas analysis changes in air embolized cats were investigated. Under general anesthesia with Halothane, cats were injected 1ml/kg of air acutely to decrease mean arterial pressure(MAP) about 30 to 40 percent of control value through superior vena cava. 14 cats were divided into two groups of 7 each (group 1 and 2). Group 1 cats received NE and then NE with NTG therapies. In group 2, ISO and then ISO with NTG therapies were taken. The results were as follows: 1) Hemodynamic changes. Group 1: NE increased the MAP from 69+/-8 mmHg(mean+/-SD) to 116+/-14mmHg(p<0.05), decreased the right atrial pressure(RAP) from 18+/-4mmHg to 11+/-3mmHg(p<0.05). Combined therapy with NTG decreased the MAP from 116+/-14 mmHg to 101+/-10 mmHg(p<0.05), the HR from 167+/-16 beats/min(bpm) to 150+/-4 bpm(p<0.05), the RAP from 11+/-3 mmHg to 8+/-3mmHg(p<0.05). Group 2: ISO increased the MAP from 81+/-8mmHg to 112+/-14 mmHg(p<0.05), and the HR from 152+/-21 bpm to 190+/-24 bpm(p<0.05). Combined therpy with NTG decreased the HR from 190+/-24 bpm to 174+/-19 bpm(p<0.05), the CVP from 14+/-7mmHg to 14+/-3mmHg(p<0.05), and the RAP from 13+/-3mmHg to 12+/-3mmHg(p<0.05). 2) Blood gas analysis changes. Group 1: NE with NTG combined therapy increased the arterial oxygen tension from 335+/-54 mmHg to 372+/-49mmHg, decreased the venous CO2 tension from 52+/-9mmHg to 47+/-4mmHg. Group 2: ISO with NTG combined therapy increased the arterial oxygen tension from 344+/-85mmHg to 375+/-50mmHgIp<0.05). (paired t-test, p<0.05). In conclusion, NE and ISO increased MAP in venous air embolism with moderately decreased MAP. Inotropic agent with NTG therapy improved arterial oxygenation.