(1152) Outcomes of Adjusted Pressure Support Weaning From Mechanical Ventilation: Retrospective Study

Introduction: Studies have shown Respiratory therapist (RT) driven weaning protocols improve patient outcomes. Long term acute care facilities follow protocols with gradual reduction of pressure support (PS) at fixed time intervals, standard pressure support weaning (SPSW). We had observed larger tidal volumes (VT) over 500 ml in some patients while using SPSW likely due to differences in lung compliance. We therefore decided to adjust the PS to VT 300 to 400 ml with respiratory rate (RR) < 30 , adjusted pressure support weaning ( APSW) to see if some of these patients can be weaned off earlier than SPSW.

Methods: Patients admitted with respiratory failure on mechanical ventilation from January 1st to May 30th 2023 were reviewed. Patients passed Spontaneous breathing trial with PS12cm for 1 hour (VT>300ml with RR < 30 and comfortable) were placed on weaning protocol. SPSW starts with Pressure support (PS) 12 cm; weaning time is increased and PS decreased at fixed time and pressures with option to skip steps ( January to march data was reviewed). Educational in service was given on APSW, which starts with PS 12cm, then PS is adjusted up 2cm if Vt is >500ml or down 2cm if Vt is < 300ml to match Vt 300-400 ml with RR < 30 ( April and May data was reviewed ). Pressure support days were compared between the two methods and grouped as 0-10, 11-19 and >20 days which was the primary outcome. Secondary outcomes studied were mortality and re ventilation rates.

Results: 60 patients met the inclusion criteria. 32 were in SPSW (53%) with mean age of 65+/- 13 years with 71.8% males and 28% females. 28 were in APSW (47%) group with mean age of 57 +/- 13 years with 60% males and 40% females. The APSW had higher odds of successful weaning over 0-10 and 11-19 PS days with aOR of 3.3 and 1.7 respectively. Mortality rate was lower with the APSW compared to the SPSW (3.6 % vs. 6.3%).

Weaning Method SPSW APSW
RE VENTILATION 10 (31.30%) 5(17.90%)
TRACH COLLAR 15 (46.90%) 11(39.30%)
TRACH DECANNULATED 5 (15.60%) 11(39.30%)
DEATH 2(6.30%) 1(3.60%)
TOTAL 32 (100%) 28(100%)

Conclusions: APSW was associated with higher chance of early liberation of mechanical ventilation within 10 and 11-19 days with fewer patients returned to full ventilation after successful weaning and has lesser mortality compared to SPSW.