The Science Journal of the American Association for Respiratory Care
BACKGROUND: The Cleveland Clinic Children's Hospital admits > 900 patients per year to the PICU and performs > 500 open-heart surgeries on children with congenital heart disease. Many of these patients receive short-term ventilation, therefore we believed it would be beneficial to test the efficacy of the use of HME (heat moisture exchanger with bacterial/viral filter) devices in this pediatric patient population. The use of pediatric HME's on short-term ventilator patients, can result in cost savings and may help to reduce the rate of ventilator induced infections. Presently heated wire circuits containing a humidifier canister, a transfer set, a one liter bag of sterile water, and a bacteria filter costs approximately $17.80. A standard non-heated wire circuit costs approximately $6.00 with each HME costing approximately $2.50. If we can safely and effectively use HME devices on these pediatric patients, we can save $6.80 to $9.30 per patient. This could result in annual cost savings of up to $5,000.00 for equipment purchases alone. Additional benefits may be the elimination of condensation within the ventilator circuit resulting in less inadvertent patient lavage, and a reduction in nosocomial pulmonary infections from the bacterial and viral static properties of the HME filter. METHOD: All intubated patients weighing > 8 kg were placed on the appropriate HME device (as determined by weight), and an evaluation was performed at the time of extubation to determine the effects on the patient. The evaluation criteria included the type of HME device, the amount of VD (dead space) required to compensate for the HME volume, the duration of use, the reason for discontinuation, and adverse effects. Microbiology culture results from the expiratory limb of the ventilator circuit are ongoing to test the efficacy of the HME filter. All HME devices were changed every 24 hours and all patients were placed on standard humidification devices following 48 hours of mechanical ventilation. Patients with pulmonary hemorrhage, pulmonary edema, and pneumonia with thick tenacious secretions were excluded from the evaluation. The evaluation process took place over a three week period and consisted of 22 patients.
Results: None of the 22 patients required early discontinuation of the HME device, 14%(3) of the patients required VD compensation (volumes equaling the VD volume of the HME device), none were noted to have documented adverse effects (increased secretions, mucus plugging, or increased WOB), and all were successfully extubated within the first 24 hours of mechanical ventilation. Patients evaluated ranged from 8.1 kg - 90 kg with an average weight of 39 kg, and the average preset VI for all patients was 10.1 ml/kg. The majority of patients (77%) were intubated > 4 hours but < 24 hours, and the remainder were intubated for < 4 hours. We also observed that the ventilator circuit was completely dry on the inspiratory and expiratory limb with minimal condensation noted at the ETT thus eliminating inadvertent patient lavage.
Conclusions: 1. It appears that HME devices can be safely used in select pediatric patients requiring short term mechanical ventilation in the absence of chronic lung disease. 2. Significant cost savings can be realized. 3. We are currently testing for the presence of organisms in the expiratory limb of the ventilator circuit to evaluate the effectiveness of the HME filter.