AN IMPROVED NASAL PRONG APPARATUS FOR END-TIDAL CARBON-DIOXIDE MONITORING IN AWAKE, SEDATED PATIENTS

被引：21

作者：

ROY, J

MCNULTY, SE

TORJMAN, MC

机构：

[1] Department of Anesthesiology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, 19107, PA

来源：

JOURNAL OF CLINICAL MONITORING | 1991年 / 7卷 / 03期

关键词：

MEASUREMENT TECHNIQUES; CAPNOGRAPHY; EQUIPMENT; CANNULAS; MONITORING; END-TIDAL;

D O I：

10.1007/BF01619269

中图分类号：

R614 [麻醉学];

学科分类号：

100217 ;

摘要：

We describe and evaluate a new apparatus that monitors end-tidal carbon dioxide (PETCO2) and augments the inspired oxygen concentration in awake, sedated patients. The unit was evaluated for its effectiveness as an oxygenation device and its accuracy as a predictor of PaCO2 through the correlation of PaCO2 with PETCO2. Twenty cardiac surgical patients, physical status ASA 2-4, participated in this study. The PETCO2 monitoring device consisted of a dual-prong nasal oxygen cannula and a 14-gauge intravenous catheter that was inserted into one limb of the oxygen supply tubing and connected to a Datex gas analyzer (Datex Instrumentation Corp, Helsinki, Finland) to measure PETCO2. The cross-over passage between the prongs was intentionally blocked with the end of a wooden-core cotton swab. The oxygen flow rates were randomly varied (2, 4, and 6 L/min) every 5 minutes, and values for PETCO2 as well as arterial blood samples for analysis of PaCO2 and PaO2 were obtained at the end of each 5-minute period. The accuracy of the system was assessed by comparing the PaCO2-PETCO2 differences (bias) at each oxygen flow rate. The ratios of PETCO2 compared with PaCO2 were 0.98, 0.94, and 0.85, with correlation coefficients of r = 0.81, 0.85, and 0.63, respectively. The PaO2 values were 114, 154, and 183 mm Hg for the corresponding nasal oxygen flow rates of 2, 4, and 6 L/min, respectively. This study indicates that this modified nasal cannula provides supplemental oxygen adequately and yields a satisfactory reflection of the PaCO2 depending on the oxygen flow rate delivered.

引用

页码：249 / 252

页数：4

共 13 条

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