Mouth occlusion pressure (P0.1) in acute respiratory failure

Abstract

We studied 20 unselected patients admitted to our Intensive Care Unit (ICU) suffering from acute respiratory failure (ARF), who needed mechanical ventilatory support. In all of them we followed a prospective protocol to investigate the value of mouth occlusion pressure (P0.1) as an indicator for weaning. Fifty-two tests were classified into three groups: a need to be reconnected to mechanical ventilation (MV), stable on intermittent mandatory ventilation (IMV), or spontaneous breathing on a T-tube (TT). The results showed that at increased values of P0.1 there were more difficulties in weaning patients from MV. Seventy-eight percent (78%) of the occasions where weaning was successful, values of P0.1 were less than or equal to 4.2 cm H2O, in chronic or non-chronic patients. Eighty-nine percent (89%) of the times when P0.1 values were higher than 4.2 cm H2O the same patients required ventilatory support, total (MV) or partial (IMV). These differences were statistically significant (p less than 0.01). We conclude that the P0.1 is an easily obtained non-invasive parameter, that can contribute along with other more conventional measurements to a superior indication for weaning.

Breathing pattern during acute respiratory failure and recovery

“…The increased P0.1 during ARF is in agreement with previous studies [22]. Although P0.1 was larger in FW compared to SW patients, in contrast to other studies [23][24][25], the difference in mean P0.1 between these groups did not achieve statistical significance. Similarly, P0.1/PI,max did not separate the FW and SW patients.…”

“…The predictive value of P0.1 to indicate FW or SW has been questioned by others [26], who were only able to separate FW and SW patients by a difference in hypercapnic augmentation of P0.1. Nevertheless, most studies [22][23][24][25] have demonstrated that neuromuscular output is augmented in ARF and FW patients. It should be emphasized that the present study did not address the utility of these measured variables in predicting weaning outcome, but they were used to assess differences in the physiological characteristics between FW patients and those with ARF.…”

Mouth occlusion pressure as a useful indicator for weaning from mechanical ventilation.

“…Herrara et al (1985) and Sassoon (1987) have obtained similar results. Herrara et al (1985) reported that the patients with Po ., greater than 4.2 cmH2O failed in weaning.…”

Preliminary Evaluation of a New Index to Predict the Outcome of a Spontaneous Breathing Trial

“…3,11 We previously found P 0.1 to be a valuable index of respiratory-center output, 12 and it has a high enough sensitivity and specificity to contribute to better guidance of weaning from mechanical ventilation. 13 We devised the CORE index:…”