Comparacion de la presion arterial y transcutanea de oxigeno en la fibrobroncoscopia

[Usefulness of transcutaneous carbon dioxide pressure monitoring to measure blood gases in adults hospitalized for respiratory disease]

OBJECTIVE

To evaluate the usefulness of transcutaneous carbon dioxide pressure (TcPCO2) monitoring in patients hospitalized for respiratory disease.

PATIENTS AND METHODS

We used a SenTec TcPCO2 monitor that also determines transcutaneous oxygen saturation (SpO2) by means of a sensor placed behind the ear lobe at a temperature of 42 degrees C. We compared arterial blood gas measurements--PaCO2 and arterial oxygen saturation (SaO2)--with transcutaneous measurements and analyzed the correlation, regression line, and agreement between the 2 methods.

RESULTS

Thirty patients (20 men and 10 women) with various respiratory diseases and a mean (SD) age of 71 (13) years were included in the study. The median TcPCO2 was 43.25 mm Hg and the median PaCO2 was 42.6 mm Hg with no significant differences between the 2 measurements. The correlation was significant (rho=0.979; P< .0001) and the corresponding regression equation was TcPCO2=-2.475+1.058 PaCO2. The mean difference was 0.16 mm Hg (95% confidence interval [CI], --0.74 to 1.06). The lower limit of agreement (mean -1.96 SD) was -4.64 mm Hg, and the upper limit (mean +1.96 SD) was 4.96 mm Hg. For SaO2, the median was 94% and for SpO2, 95%. The difference between the 2 medians was significant (P< .004). The correlation was also significant (rho=0.822; P< .0001) with SpO2=4.427+0.97 SaO2. The mean difference was 1.14% (95% CI, 0.381% to 1.899%). The lower limit of agreement (mean -1.96 SD) was --2.93% and the upper limit (mean +1.96 SD) was 5.21%

CONCLUSIONS

Transcutaneous determination of carbon dioxide pressure and oxygen saturation is useful for patients hospitalized for respiratory disease in view of its good correlation and agreement, although SpO2 does tend to overestimate SaO2.

[Description of a new procedure for fiberoptic bronchoscopy during noninvasive ventilation through a nasal mask in patients with acute respiratory failure]

A new method is described for performing oral fiberoptic bronchoscopy during noninvasive ventilation through the nose. The technique was successfully applied in 2 patients suffering from acute respiratory failure. The bronchoscope was inserted through a glove finger fitted into a mouth guard. The system works as a valve and does not affect performance of the bronchoscopy procedure or the pressures administered during noninvasive ventilation. We conclude that the procedure has potential advantages over bronchoscopy through the nose and face masks or helmets, particularly for the management of secretions or in special clinical circumstances (hemoptysis or presence of foreign bodies). This method can be used to substitute for or complement other bronchoscopy techniques performed with other interfaces.