AGS: Protocol Shortens Time on Ventilator

By Peggy Peck
WASHINGTON, 10 may 2008 -- ICU patients put on a coordinated, combination weaning protocol spent three fewer days on a ventilator than those for whom traditional methods were used, researchers here reported.The intervention, called the "wake up and breathe" protocol, combines tests of spontaneous breathing along with a reduction in sedative use to trigger awakening, Timothy Girard, M.D., of Vanderbilt University in Nashville, Tenn., told attendees at the American Geriatrics Society meeting. The protocol has demonstrated efficacy in younger adults, but had not previously been tested in older patients, Dr. Girard said. Presenting results of a prespecified subgroup analysis from the Awakening and Breathing Controlled (ABC) Trial, Dr. Girard said that longer ventilator use was associated with worse outcomes, so several strategies aimed at shortening ventilator time have been studied.
"In general the weaning period, the period following fulminate disease, is considered the most amenable to shortening," he said.
Previous studies have investigated weaning with trials of spontaneous breathing, in which the ventilator is turned off or very low and the patient is observed to see if he or she is able to breathe on his or her own. Typically, this test is conducted by a respiratory therapist.
Other studies have investigated spontaneous awakening in which sedation is turned off and the patient is observed for signs of agitation or other problems. Such sedation management is usually handled by nurses.
The two processes are not necessarily coordinated.
In this study, "we developed a very streamlined process that combined both sedation and mechanical support," Dr. Girard said.
The patient was first evaluated to determine if he or she was a candidate for a trial of awakening using a safety screen that evaluated use of paralytics, pain, agitation, whether the patient was suffering alcohol withdrawal, and other factors.
If the patient passed the safety screen, "we had the green light to turn off the sedation," he said. A patient passed this stage of the protocol if he could respond to a simple command to open his eyes.
Patients who failed the trial were again sedated and the protocol was attempted again the following day.
Patients who passed the wake-up stage proceeded to the "breathe" stage of the protocol. Again they were evaluated with a safety screen that assessed weaning risks.
If they passed that safety screen, the ventilator was turned off or to a very low level, and the patient was closely observed for two hours. Patients who completed the two-hour trial without incident were extubated, those who had difficulty were returned to increased or full ventilator support.
The study endpoint was number of days free of ventilator support.
The trial, which was conducted at four participating centers, enrolled 335 mechanically ventilated patients, including 147 who were 65 or older. Consent, Dr. Girard said, was usually obtained from a family member because most patients could not communicate.
Patients were randomized to the wake up and breathe intervention or to usual care in which both ventilator weaning and sedation were managed based on sporadic clinical observation.
Overall, the intervention was associated with a three-day reduction in ventilator time and, for the oldest patients, "those in their 70s, the reduction was four days, which was statistically significant (P=0.04)," Dr. Girard said.
Average coma time was two days shorter (P=0.03) for the intervention patients and ICU stay was seven days shorter (median stay six days versus 13 days P=0.02), he said.
One-year mortality was also lower in the intervention group (37 deaths versus 52 in the control group), but that difference was not statistically significant.
Most importantly, Dr. Girard said, was "the homogeneity tests for treatment interaction with age. The treatment effects in older patients did not differ significantly from those observed in younger patients."
The study was funded by the Saint Thomas Foundation, Hartford Geriatrics Health Outcomes Research Scholars Award Program, Vanderbilt University, and the National Institutes of Health.
Dr. Girard reported no conflicts of interest.

Primary source: American Geriatrics SocietySource reference:Girard TP, et al "Outcomes among older mechanically ventilated icu patients treated with a wake up and breathe protocol" P 34.