Comparison of Pressure Support and T-tube Weaning from Mechanical Ventilation: Randomized Prospective Study

Aim: To compare T-tube and pressure support ventilation (PSV) as two methods of weaning patients from mechanical ventilation.

Methods: A randomized prospective study included 260 patients who received mechanical ventilation for more than 48 h, and who were admitted to the intensive care unit (ICU) at Dr. Josip Bencevic General Hospital in Slavonski Brod, between August 1999 and October 2000. After fulfilling the clinical criteria for weaning, the patients were randomly assigned to a 2-h trial of spontaneous breathing either with a T-tube system (n=110) or PSV of 8 cm H2O (n=150). The patients who fulfilled weaning criteria at the end of the 2-h trial were extubated. If any signs of poor procedure tolerance were observed during the 2-h trial, the mechanical ventilation was reinstituted. In such patients, the same weaning procedure was repeated after 24 h, or when the patient's clinical condition permitted. Two methods of weaning were compared according to the patient's clinical characteristics, objective parameters, and procedure outcome.

Results: Eighty (73%) patients in the T-tube group and 120 (80%) patients in PSV group successfully completed the 2-h trial and were extubated. Thirty patients in the T-tube group and 30 in the PSV group had weaning difficulties. Total length of additional mechanical ventilation and total length of stay at ICU were significantly shorter in patients undergoing PSV weaning (p<0.001 for all, Man-Whitney test). For the patients with weaning difficulties and Acute Physiology and Chronic Health Evaluation (APACHE) II score >20 on admission, PSV was the superior method of weaning according to rate of successful extubation, time of weaning from mechanical ventilation, total time of mechanical ventilation, and length of ICU stay (p<0.001 for all, Man-Whitney test).

Conclusion: In patients with weaning difficulties, PSV with 8 cm H(2)O was more successful weaning method than T-tube.