2001 OPEN FORUM Abstracts
Effectsof an In-line IPV Interface versus Adjustable PEEP Valve Attachment During IntrapulmonaryPercussive Ventilation
KathleenDeakins RRT, Robert Chatburn RRT FAARC, Julie DeFiore BSEE and TimothyMyers BS, RRT. Rainbow Babies & Children?s Hospital, Cleveland, Ohio.
Introduction:Intrapulmonary Percussive Ventilation (IPV) is a therapeutic modality designedto mobilize and facilitate the removal of retained secretions, re-expand areasof collapse, increase deposition of aerosolized particles and improve gas exchange.IPV is routinely ordered in our institution for the treatment of atelectasis,and for mobilization of secretions in mechanically ventilated pediatric patients.Our current practice is to remove the patient from the mechanical ventilator,attach the IPV breathing circuit to the artificial airway, and percuss manuallyby depressing the remote switch. In patients requiring high mean airway pressures(MAP), we have observed episodes of acute desaturation when IPV is deliveredin this manner. It is our hypothesis that removal of the patient from the ventilatorcauses significant reduction in PEEP, the loss of alveolar recruitment, lossof MAP, and desaturation. The purpose of this bench study was to compare theeffects of maintaining peak IPV pressure and PEEP, while delivering IPV in-linewith the mechanical ventilator to an alternative method using a spring loadedadjustable PEEP valve attachment to the IPV breathing circuit.
Methods:BaselineIPV pressure settings (PIP and PEEP) were established by selecting predeterminedpressures and verifying them on a Gould Brush 2400-4 channel chart recorder(Gould Corp.). IPV frequency was manually counted. In this laboratory evaluation,the IPV Percussionator Ventilator (Percussionaire Corp.) with its standard breathingcircuit and interfacing assembly was attached to the inspiratory limb of anadult ventilator circuit at the patient wye ona Bird V.I.P. ventilator (BIRD Corp.). As an alternative to the in- line setup,an AMBU peep valve, (AMBU Inc.) was attached to the standard IPV breathing circuitat the exhaust port of the Phasitron assembly, for IPV delivery independentof the ventilator. Both setups were connected separately to a 4.0 endotrachealtube (10 cm long) attached to the Ingmar Adult/ Pediatric Test Lung Model (IngmarInc.) Baseline pressure (PEEP), and inspiratory pressures (percussions) weremeasured with a Gould Brush 2400-4 channel chart recorder during a high frequency/low pressure IPV strategy of 200 bpm and pressure of 15 cm H20, asPEEP levels were increased from 0-20 cmH20 in 5 cm H20increments.
Results:The results from the of the actual IPV PIP and the system PEEP are given inthe tables below:
Conclusion:IPV delivered via artificial airway with a stand-alone adjustable PEEP valveattachment was better able to maintain a desired pressure gradient (PIP-PEEP)than the IPV in-line ventilator setup. IPV with a PEEP valve attachment canbe used to maintain adequate PEEP levels in clinical states requiring high PEEP.