2000 OPEN FORUM Abstracts
PRESSURE SUPPORT LEVELS FOR SUCCESSFUL WEANING FROM MECHANICAL VENTILATION
Glen R. Coddington, RCP, RRT, Kaiser Permanente, Orange County Medical Center, Anaheim, Ca
BACKGROUND: A recent study (Am J Respir Crit Care Med 1998 Dec) demonstrated that T-tube trials of a few hours in duration may serve as an indicator of a patient's ability and readiness to be weaned from mechanical ventilation. Another study utilized the technique of placing the patient on a Pressure Support of 18 cmH2O and then reducing the pressure 2 to 4 cmH20 per day as tolerated. Although both studies suggest that these methods may be somewhat effective, they require additional utilization of Respiratory staffing resources, as well as the associated cost of materials and supplies. PURPOSE: To identify and demonstrate an optimal pressure support levels that successfully promote weaning from mechanical ventilation without utilizing labor and time intense T-tube or Pressure Support trials. METHOD: A sample population of 100 patients requiring invasive mechanical ventilation were randomly selected and retrospectively reviewed to evaluate what pressure support levels were utilized immediately prior to discontinuing mechanical ventilation. Mechanical ventilation for all patients in the study was performed using the Puritan Bennett 7200AE ventilator. Neonates (<6 months) and "DNR" (Do Not Resuscitate) patients were excluded from the study criteria. However, 2 pediatric patients (ages 15 and 17) that were cared for in our adult ICU were included in the study. Unsuccessful weaning was defined as re-institution of mechanical ventilation within 72 hours and was determined by the patient's clinical presentation and pertinent invasive and non-invasive data.
EXPERIENCE: The QI tool developed by our Respiratory Care Services Department proved extremely useful for outcome analysis of ventilator management. CONCLUSION: There was a 96% success rate when weaning patients from mechanical ventilation utilizing a mean pressure support level of 13.2 cmH20 and this may be a highly effective and less resource alternative to T-tube and Pressure Support trials. However, additional data would be helpful to better suggest which management technique should be utilized for different patient populations. With so many variables involved with the weaning process, it would behoove us as bedside clinicians to note a conclusion that was reached in another study (Crit Care Med 1999 Nov) that stated: "The manner in which the mode of weaning is applied may have a greater effect on the likelihood of weaning than the mode itself". (See Original for Figure)