2005 OPEN FORUM Abstracts
RESULTS OF FULL YEAR OF FLEXIBLE PROTOCOL FOR ALI/ARDS INCORPORATING ARDSNET-TYPE PROTECTIVE STRATEGIES.
John W Farnham, RRT; Sharon K Foust, RRT; Steven M Bohanan, RRT. Respiratory Care Services, University of Tennessee Medical Center, 1924 Alcoa Highway, Knoxville, TN 37920.
Background: Last year we reported initial results of beginning to use a flexible, three-armed protocol in supporting patients suffering from Acute Lung Injury (ALI) or Acute Respiratory Distress Syndrome (ARDS). Last year's report was written in June after having initiated use of the protocol in May. The protocol was designed to allow clinician flexibility in the choice of either a verbatim ARDS-Net strategy, a Pressure Control Ventilation (PCV) strategy, or an Airway Pressure Release Ventilation (APRV) strategy. Both the alternate strategies to ARDS-Net incorporated the basic ARDS-Net principles of low tidal volume (VT) and low plateau pressure (PPLAT). Our original results included a cohort of 39 patients. The study cohort had a mortality rate of 39.3%, representing an improvement of 11.1%, compared to the mortality rate of 50.4% mortality rate in all ALI/ARDS patients of the full year prior to initiation of the protocol.
Methods: We continued monitoring all ALI/ARDS patients, capturing data from the bedside and importing it into a spreadsheet for later analysis. The data collected included information as to which arm of the protocol was used, description of complications, mortality outcome, and some demographic and length of stay data. Our process remained that the attending physician could choose the initial ventilator strategy, and, dependent on results, could flex between the other strategies as best served the patient.
Results: For the year of monitoring, the total patient cohort was 128. Of that number, 33 died, for a mortality rate of 25.7%. That represents a 49% improvement in mortality rate, compared to the pre-protocol year, in the period of a year of protocol use. Of 113 patients for whom mode was documented, 66 received ARDS-Net, 39 received PCV, and 8 received APRV. Out of the entire cohort studied, at least one switch of modes was documented on 7 patients. Of the patients who died, 28 had documentation of mode used. 17 had been on ARDS-Net, 10 on PCV, and 1 on APRV.
Conclusions: The development and use of protocol strategies for the management of ALI/ARDS resulted in a clear and significant improvement in the one meaningful outcome for ALI/ARDS patients: that of mortality. Comparing the mortality rate of the immediate year prior to the implementation of the protocol to the full year after implementation, we see the mortality rate essentially cut in half. Although complete studies to reveal the statistical relationship, if any, of the mode used to the mortality rate have not been completed, observation has led us to anticipate that there may be no statistical correlation of mode to mortality so long as low VT and low PPLAT principles are adhered to. More in-depth research to reveal the details and to allow more meaningful statistical analysis is to begin shortly, and should reveal more useful information. Based on mortality rate improvement, the use of this protocol to manage ALI/ARDS is considered a success and will be continued. Protocol refinements will continue as warranted by continued observation and critical assessment.