2004 OPEN FORUM Abstracts
Comparison of Patient Comfort during Pressure Regulated Volume Control (PRVC) and Assist Control (AC) Mechanical Ventilation
John
Crawford, RRT
Purpose: Pressure Support
Ventilation (PSV) has been reported to be more comfortable than AC
during non-invasive positive pressure ventilation. This
may be due to the ability of PSV to allow the patient to control
rate, flow, volume and pattern. However, patient comfort in these
modes and PRVC in intubated patients has not been studied. Our
study aimed at determining comfort in these modes in intubated
patients.
Methods: Twelve patients who
were intubated, stable, and able to mark a line on a 100 mm visual
analog scale (VAS) were enrolled in the study. They were being
ventilated in PRVC before switching them to PSV and AC for 30 minutes
each. AC volume was 8cc/kg and pressure support level was set at
(Plateau Pressure-Positive End Expiratory Pressure) to target a
minimum tidal volume of 8cc/kg. After each mode, patients were asked
to mark their comfort level on the VAS (very comfortable=100,
uncomfortable=0). Physiologic parameters were also recorded. Paired
t-testing was used to analyze the results.
Results: We report only a subset
of the study results here. After analyzing the data, we have found no
significant difference in patient perceived comfort between PRVC
(mean=61) and AC (mean=68), p=0.37. Also, we didn’t find any
statistical difference between the two modes in terms of physiologic
parameters including blood pressure, heart rate, respiratory rate,
oxygen saturation, mean airway pressure and minute ventilation.
Conclusion: Our data shows that
PRVC and AC are not statistically different from each other in terms
of patient comfort. Our study is limited by the difficulty in finding
mechanically ventilated patients in the medical ICU who are both
clinically stable and able to use a VAS to accurately mark their
comfort level. In addition, other modes of mechanical ventilation
such as volume support, proportional assist, and PSV may potentially
be more comfortable than either PRVC or AC.
Clinical
Implications: Patient comfort is an
essential component of medical critical care. Further studies need to
be done with larger study population to compare different modes of
mechanical ventilation to find the most comfortable mode for the
patient.