Korean J Anesthesiol Search

CLOSE


Korean Journal of Anesthesiology 1998;34(2):280-293.
DOI: https://doi.org/10.4097/kjae.1998.34.2.280   
Changes in Hemodynamic and Oxygen Availability with Apnea under Halothane Anesthesia.
Young Ho Jang, Jung Kil Chung, Jae Kyu Cheun, Dae Kyu Song
1Department of Anesthesiology, School of Medicine Keimyung University, Taegu, Korea.
2Department of Physiology, School of Medicine Keimyung University, Taegu, Korea.
Abstract
BACKGROUND
Varying results of hemodynamic and oxygen parameters in response to hypoxia and/or hypercarbia have been reported. In this study, the effects of apnea on the hemodynamic parameters and oxygen availability were evaluated using ten healthy mongrel dogs.
METHODS
After full oxygenation, apnea was induced by disconnecting animals from mechanical ventilation. Hemodynamic parameters, oxygen delivery, consumption and extraction ratio were measured at one minute intervals until the cardiac output was undetectable via the thermodilution method.
RESULTS
Blood pressure (BP) increased continually following apnea. Cardiac output (CO) increased during the early of apnea (2 and 3 minute) but decreased thereafter. Systemic vascular resistance (SVR) decreased in the early phase of apnea but subsequently declined. The indices of preload increased steadily following apnea. Changes in heart rate (HR) were compared with changes in CO and oxygen delivery, and was found to increase during the early phase of apnea (2~3 minutes) and decrease thereafter. The oxygen extraction ratio did not change significantly and remained steady 6 minutes after apnea but increased and became irregular thereafter.
CONCLUSIONS
These data suggest that early reflex responses such as increased BP were primarily due to increased CO, whereas the late increase in BP was due to the increase of SVR. We conclude that BP is not meaningful variables in evaluating critical hypoxic condition such as apnea, and bradycardia might be caused by decreased CO and severe hypoxemia.
Key Words: Hypoxia; Oxygen: consumption; Ventilation: apnea


ABOUT
ARTICLE CATEGORY

Browse all articles >

BROWSE ARTICLES
AUTHOR INFORMATION
Editorial Office
101-3503, Lotte Castle President, 109 Mapo-daero, Mapo-gu, Seoul 04146, Korea
(서울특별시 마포구 마포대로 109 롯데캐슬 프레지던트 101동 3503호)
Tel: +82-2-792-5128    Fax: +82-2-792-4089    E-mail: journal@anesthesia.or.kr                
Business Name: Korean Society of Anesthesiologists (대한마취통증의학회)
Business Registration: 106-82-07194
Representative: Jun Heum Yon (연준흠)

Copyright © 2024 by Korean Society of Anesthesiologists.

Developed in M2PI

Close layer
prev next