The oxygen consumption and oxygen cost of breathing before and after thoracotomy
- VernacularTitle:开胸手术前后氧耗量和呼吸氧价的变化
- Author:
Gongjian LIU
;
Hao JIANG
;
Yinming ZENG
- Publication Type:Journal Article
- Keywords:
Thoracotomy;
Postoperative period;
Oxygen consumption;
Work of breathing
- From:
Chinese Journal of Anesthesiology
1996;0(07):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the changes in oxygen consumption ( VO2 ) and oxygen cost of breathing(OCB) in postoperative patients and the effects of various kinds of assisted ventilatory support on OCB.Methods Twenty patients (13 male, 7 female), aged 43-70 years, undergoing thoracic surgery were divided into two groups: (A) pulmonary disease(PD) group in which patients had chronic pulmonary disease and abnormal pulmonary function( n = 10); non-pulmonary disease (NPD) group in which patients had no chronic pulmonary disease and their pulmonary function was normal ( n = 10). Operation were performed under combined intravenous-inhalation anesthesia or general-epidural anesthesia. Metabolism of the patients was measured before anesthesia. After operation the patients were mechanically ventilated in ICU and PaCO2 was maintained between 4.6-6.0 kPa. Metabolism was measured 12h after operation when anesthesia had worn off, the patients were fully awake and breathing spontaneously. Their hemodynamics was stable. Body temperature was maintained at 37℃?0.5℃ . VO2 was measured using indirect colorimetry (Datex Deltatrac MBM-200). VO2, VCO2, energy expenditure(EE) and respiratory quotient (RQ) were recorded every minute for 30 min. OCB was calculated by deducting VO2 measured during controlled ventilation from VO2 measured during spontaneous breathing( OCB = VO2 spontaneous breathing - VO2 controlled ventilation) and expressed by OCB/VO2 spontaneous breathing ( % ) . During mechanical ventilation FiO2 was set
