Comparison of patient-ventilator asynchrony during pressure support ventilation and proportional assist ventilation modes in surgical Intensive Care Unit: A randomized crossover study.
BACKGROUND
The patient-ventilator asynchrony is almost observed in all modes of ventilation, and this asynchrony affects lung mechanics adversely resulting in deleterious outcome. Innovations and advances in ventilator technology have been trying to overcome this problem by designing newer modes of ventilation. Pressure support ventilation (PSV) is a commonly used flow-cycled mode where a constant pressure is delivered by ventilator. Proportional assist ventilation (PAV) is a new dynamic inspiratory pressure assistance and is supposed to be better than PSV for synchrony and tolerance, but reports are still controversial. Moreover, most of these studies are conducted in chronic obstructive pulmonary disease patients with respiratory failure; the results of these studies may not be applicable to surgical patients. Thus, we proposed to do compare these two modes in surgical Intensive Care Unit (ICU) patients as a randomized crossover study.


OBJECTIVE
Comparison of patient-ventilator asynchrony between PSV and PAV plus (PAV+) in surgical patients while weaning.


METHODS
After approval by the Hospital Ethics Committee, we enrolled twenty patients from surgical ICU of tertiary care institute. The patients were ventilated with pressure support mode (PSV) and PAV+ for 12 h as a crossover from one mode to another after 6 h while weaning.


RESULTS
Average age and weight of patients were 41.80 ± 15.20 years (mean ± standard deviation [SD]) and 66.50 ± 12.47 (mean ± SD) kg, respectively. Comparing the asynchronies between the two modes, the mean number of total asynchronous recorded breaths in PSV was 7.05 ± 0.83 and 4.35 ± 5.62, respectively, during sleep and awake state, while the same were 6.75 ± 112.24 and 10.85 ± 11.33 in PAV+.


CONCLUSIONS
Both PSV and PAV+ modes of ventilation performed similarly for patient-ventilator synchrony in surgical patients. In surgical patients with acute respiratory failure, dynamic inspiratory pressure assistance modalities are not superior to PSV with respect to cardiorespiratory function.
Department of Critical Care Medicine and Anaesthesiology, Dayanand Medical College and Hospital, Ludhiana, India.
Parshotam Lal
PL
Gautam
Department of Anaesthesia and Intensive Care, SGRD Medical College and Hospital, Amritsar, Punjab, India.
Gaganjot
G
Kaur
Department of Critical Care Medicine and Anaesthesiology, Dayanand Medical College and Hospital, Ludhiana, India.
Sunil
S
Katyal
Department of Anaesthesia and Intensive Care, SGRD Medical College and Hospital, Amritsar, Punjab, India.
Ruchi
R
Gupta
Department of Anaesthesia and Intensive Care, SGRD Medical College and Hospital, Amritsar, Punjab, India.
Preetveen
P
Sandhu
Department of Critical Care Medicine and Anaesthesiology, Dayanand Medical College and Hospital, Ludhiana, India.
Nikhil
N
Gautam
Patient-ventilator dyssynchrony; pressure support ventilation; proportional assist ventilation