Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form

Effects of continuous, expiratory, reverse, and bi-directional tracheal gas insufflation in conjunction with a flow relief valve on delivered tidal volume, total positive end-expiratory pressure, and carbon dioxide elimination: A bench study

Delgado, E and Hete, B and Hoffman, LA and Tasota, FJ and Pinsky, MR (2001) Effects of continuous, expiratory, reverse, and bi-directional tracheal gas insufflation in conjunction with a flow relief valve on delivered tidal volume, total positive end-expiratory pressure, and carbon dioxide elimination: A bench study. Respiratory Care, 46 (6). 577 - 585. ISSN 0020-1324

[img] Plain Text (licence)
Available under License : See the attached license file.

Download (1kB)

Abstract

INTRODUCTION: Tracheal gas insufflation (TGI) can increase total positive end-expiratory pressure (total-PEEP) when flow is delivered in a forward direction, necessitating adjustments to maintain total-PEEP constant. When TGI is delivered throughout the respiratory cycle, additional adjustments are needed to maintain tidal volume (VT) constant. OBJECTIVE: Determine if bidirectional TGI (bi-TGI) (simultaneous flows toward the lungs and upper airway) in combination with a flow relief valve eliminates the increase in total-PEEP and maintains a constant VT, thus simplifying TGI administration. METHODS: Using an artificial lung model and pressure control ventilation, we studied the effect of TGI at 10 L/min on inspired VT, total-PEEP, and CO2 elimination during 6 conditions: (1) control (no TGI, no catheter in the airway), (2) baseline (catheter in the airway but no TGI), (3) continuous TGI, (4) expiratory TGI, (5) reverse TGI, and (6) bi-TGI. Each condition was studied under 3 inspiration-expiration ratios (1:1, 1:2, and 2:1). A preset flow relief valve was inserted into the ventilator circuit during all TGI conditions with continuous flow. SETTING: University research laboratory. RESULTS: CO2 elimination efficiency was similar under all conditions. Total-PEEP increased with continuous TGI and expiratory TGI, decreased during reverse TGI, and was unchanged during bi-TGI. With the flow relief valve in place, and no adjustment in mechanical ventilation, the change in minute ventilation ranged from 0% to 10%, with the least change during bi-TGI (0-5%). During bi-TGI, gas flow was equivalent in both directions during dynamic conditions and the flow relief valve consistently removed gas at 10 L/min under various pressures. CONCLUSIONS: Our data from an artificial lung model support that continuous bi-TGI minimizes the change in total-PEEP seen during other TGI modalities. The flow relief valve compensated for the extra gas volume delivered by the TGI catheter, thereby eliminating the need to make ventilator adjustments. Used in combination with a flow relief valve, bi-TGI appears to offer unique advantages by providing a simpler method to deliver TGI. Further testing is indicated to determine if similar benefits occur in the clinical setting.


Share

Citation/Export:
Social Networking:
Share |

Details

Item Type: Article
Status: Published
Creators/Authors:
CreatorsEmailPitt UsernameORCID
Delgado, E
Hete, B
Hoffman, LA
Tasota, FJ
Pinsky, MRpinsky@pitt.eduPINSKY
Date: 1 December 2001
Date Type: Publication
Journal or Publication Title: Respiratory Care
Volume: 46
Number: 6
Page Range: 577 - 585
Schools and Programs: School of Medicine > Critical Care Medicine
Refereed: Yes
ISSN: 0020-1324
PubMed ID: 11353546
Date Deposited: 20 Mar 2012 16:11
Last Modified: 24 Jun 2018 05:55
URI: http://d-scholarship.pitt.edu/id/eprint/11454

Metrics

Monthly Views for the past 3 years

Plum Analytics


Actions (login required)

View Item View Item