Hankeln K B, Gronemeyer R, Held A, Böhmert F
Department of Anesthesiology, Zentralkrankenhaus Bremen Nord, FRG.
Crit Care Med. 1991 May;19(5):642-9. doi: 10.1097/00003246-199105000-00010.
To describe the patterns of cardiac index, oxygen delivery (DO2), oxygen consumption (VO2), and oxygen deficit (or excess) and to compare invasive and noninvasive monitoring systems for evaluation of these oxygen transport patterns.
Descriptive study of oxygen transport interrelationships throughout critical illness in a consecutive series of surviving and nonsurviving patients with adult respiratory distress syndrome (ARDS).
University-affiliated city hospital.
A consecutive series of 55 critically ill patients with ARDS after shock of various etiologies.
Noninvasive VO2 was measured by a continuous, on-line, real-time device developed in our department. Inspired and expired oxygen concentrations were measured using a polarographic oxygen analyzer. Minute ventilation measurements were time integrated over 7-min intervals. Cardiac index, DO2, and VO2 were simultaneously measured invasively by pulmonary artery thermodilution catheters, together with arterial and mixed venous blood gases. There was good agreement (r2 = .60) in VO2 measured by the invasive and noninvasive methods. The estimated oxygen deficit or excess was calculated as the difference between the actual measured VO2 standardized for body temperature pressure saturated and the normative standard VO2 of each patient corrected for temperature and sedation (VO2 need). A total of 317 monitoring days in 55 patients were analyzed; 25 survivors were monitored for a mean of 4.6 +/- 2.9 days and 30 nonsurvivors were monitored for 6.9 +/- 6.6 days. Survivors had significantly higher cardiac index, DO2, and VO2 values. Generally, oxygen excesses were found in the survivors and oxygen deficit was observed in the nonsurvivors. Survivors did not reach a plateau in their DO2-VO2 patterns. In the septic nonsurviving patients and both nonseptic groups by contrast, a plateau was observed in the DO2-VO2 pattern. Surviving septic patients had a critical DO2 of 16 mL/min.kg (700 mL/min.m2) and a critical VO2 of 3.5 mL/min.kg (145 mL/min.m2).
Monitoring of VO2 and DO2 variables is useful for evaluation of tissue oxygenation and titration of therapy in critically ill patients. Noninvasive monitoring of VO2 values are in good agreement with VO2 values calculated from invasive measurements of cardiac index. The increased DO2 and VO2 values are not attributable to mathematical coupling of erroneous cardiac index values.
描述心脏指数、氧输送（DO2）、氧消耗（VO2）及氧亏缺（或过剩）模式，并比较有创和无创监测系统对这些氧转运模式的评估。
对一系列连续的成年呼吸窘迫综合征（ARDS）存活和非存活患者在危重病期间的氧转运相互关系进行描述性研究。
大学附属医院。
一系列连续的55例因各种病因休克后发生ARDS的危重病患者。
无创VO2通过我们科室研发的连续、在线、实时设备测量。使用极谱氧分析仪测量吸入和呼出的氧浓度。分钟通气量测量在7分钟间隔内进行时间积分。通过肺动脉热稀释导管同时有创测量心脏指数、DO2和VO2，以及动脉和混合静脉血气。有创和无创方法测量的VO2有良好的一致性（r2 = 0.60）。估计的氧亏缺或过剩计算为体温压力饱和标准化后的实际测量VO2与校正体温和镇静后的每位患者的标准VO2（VO2需求）之间的差值。对55例患者共317个监测日进行了分析；25例存活者平均监测4.6±2.9天，30例非存活者监测6.9±6.6天。存活者的心脏指数、DO2和VO2值显著更高。一般来说，存活者出现氧过剩，非存活者出现氧亏缺。存活者的DO2-VO2模式未达到平台期。相比之下，在感染性非存活患者和两个非感染性组中，DO2-VO2模式观察到平台期。存活的感染性患者的临界DO2为16 mL/min·kg（700 mL/min·m2），临界VO2为3.5 mL/min·kg（145 mL/min·m2）。
监测VO2和DO2变量有助于评估危重病患者的组织氧合及指导治疗滴定。无创监测的VO2值与通过有创测量心脏指数计算出的VO2值高度一致。DO2和VO2值的增加并非源于错误心脏指数值的数学耦合。
