An Observational Study to Assess the Correlation between Rapid Shallow Breathing Index and Handgrip Strength in Weaning Patients from Mechanical Ventilation

Background: Weaning patients from mechanical ventilation is a crucial part of ICU care. There are various indices and criteria to help with the same. We chose to explore the significance of HGS – Hand grip strength and RSBI – Rapid shallow breathing index. RSBI is a well-established tool to assess the patient’s progress before going in for the Spontaneous Breathing Trial - SBT. HGS on the other hand is another tool to check and ascertain the strength of the respiratory muscles.

Aim: The aim of the study was to evaluate the correlation that could exist between HGS and RSBI in order to go ahead with weaning from mechanical ventilation. This was our primary objective. The secondary objective was to recognize the difference in HGS between the groups of successful weaning and failed weaning and also to find the differences in HGS between the groups of simple weaning, difficult weaning and prolonged weaning.

Methods: In this prospective study, patients who fulfilled the criteria of being ready to be weaned off mechanical ventilation, underwent a Spontaneous Breathing Trail - SBT. During the preliminary SBT, data such as vital signs, RSBI, type of SBT, time of SBT success, and time of extubation were also collected. HGS was assessed using a Jamar dynamometer in kilograms. HGS was tested at 48 hours post intubation 10 minutes prior to SBT and 30 minutes post SBT. In addition, this measurement was also further tested 1 hour after extubation. RSBI and HGS tests were both tested 10 minutes before the SBT.

Results: Thirty-seven mechanically ventilated patients were included in this study and all these patients were also included in the final analysis. There were 24(64.86%) males. The mean age was found to be 55.32±15.58 years. APACHE II score was found to be 14.108± 5.26. Majority of the patients were intubated due to pneumonia (5%, 2 of 37 patients). The most widely used SBT in our study was pressure support ventilation (95%, 35 of 37 patients). The highest HGS was demonstrated at 1 hour post-extubation (14.14± 0.65Kg). RSBI tested 10 minutes before SBT was found to be 54.89± 9.85 breaths/min/L.

Conclusion:

This study has helped us arrive at the conclusion that HGS and RSBI seem to have a positive correlation in ICU patients who were weaned from mechanical ventilation.
RSBI is a main indicator for successful weaning.