Correlation between the P0.1 and diaphragmatic thickness fraction by ultrasound in assessment of patients’ ventilatory drive

Correlation between DTF, RSBI and P0.1 in prediction of weaning of mechanicaly ventllated patients

Abstract

Background: The diaphragm is the main muscle that powers breathing. The relative contribution of the patient’s effort during assisted breathing is difficult to measure in clinical conditions, and the diaphragm, the major muscle of inspiratory function, is inaccessible to direct clinical assessment. Several methods have been used in the research setting to assess diaphragmatic contractile activity.We studied the correlation between the p0.1 and ventilation diaphragmatic thickness fraction by ultrasound to assess thepatient’s relative contribution in breathing during mechanical.

Material and methods: In this observational study,50 mechanically ventilated patients were examined by the ultasound to measure thhe diaphragmatic thickkness fraction which was statistically correlated with the p0.1 measured on the ventilator.

Results: There is no significant statistical correlation between average P0.1, DTF, RSBI in either total, supported ventilation group or mandatory ventilation group.The only found statistically significant correlation is a negative one between P0.1 and RSBI.The ROC curve for Combination of average P0.1 of more than or equal to 0, average DTF of 26 or more and RSBI of 40 or less can predict extubation in the total studied cases, thesupported ventilation group and the mandatory ventilation group with a statistically significant P value in each category.

Conclusions: Diaphragm thickening fraction of the right diaphragm by ultrasound of more than or equal to 26% combined with RSBI of less than or equal to 40 together with P0.1 of 0 or more have improved the efficacy for prediction of successful weaning. Point-of-care ultrasound to assess diaphragm function has a steep learning curve but is ultimately achievable with excellent reproducibility. This combination between variables could help physicians decrease the ventilatory support in critically ill patients and is relatively easy to manage and cost effective.