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An automated method of separating patient from ventilator work on the lungs

International journal of clinical monitoring and computing volume 5, pages 235–242 (1988)Cite this article

Abstract

This paper describes a method of determining the amount of work on the lungs done by the patient and the ventilator using various modes of ventilation. The method uses a pneumotachograph to measure air flow, and measures pressure from an esophageal balloon and at the airway. The patient’s work is separated from the ventilator work by analysis of the esophageal pressure. When esophageal pressure is below end-expiratory esophageal pressure during inspiration, work is being done by the patient. When esophageal pressure is above end-expiratory level, the ventilator is doing the work. The calculations are done using an IBM PC computer. The studies of normal subjects show that in the assist mode with increased airway resistance, significant work by the subject is required to trigger the ventilator. Two patients are presented where the assist mode resulted in excessive amounts of work and fatal outcomes. Measurement of the mechanical work required of the patient can provide useful information for the control of ventilator therapy.

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References

  1. Marini JJ, Rodriguez RM, Lamb V. The inspiratory work-load of patient-initiated mechanical ventilation. Am Rev Respir Dis 1986; 134: 902.

    PubMed  CAS  Google Scholar 

  2. Ward ME, Corbeil C, Gibbons W, Newman S, Macklem PT. Work of breathing during mechanical ventilation as a function of peak inspiratory flow rate. Abstract. Am Rev Respir Dis 1985; 131: A131.

    Google Scholar 

  3. Ward ME, Corbeil C, Gibbons W, Newman S, Macklem PT. Role of initiating inspiratory effort in determining work of breathing during mechanically assisted ventilation. Abstract. Am Rev Respir Dis 1985; 131: A131.

    Google Scholar 

  4. Peters RM, Knight MK, Brimm JE, Hogan JS, Shelton R. A personal computer system for testing gas exchange, heart, lungs, ventilatory pump. Int J Clin Monitoring Computing 1985; 2: 113.

    Article  CAS  Google Scholar 

  5. Shackford SR, Smith DE, Zarins CK et al. The management of flail chest: A comparison of ventilatory and nonventilatory treatment. Am J Surg 1976; 132: 759.

    PubMed  Article  CAS  Google Scholar 

  6. Trinkle JK, Richardson JD, Franz JL et al. Management of flail chest without mechanical ventilation. Ann Thorac Surg 1975; 19: 355.

    PubMed  CAS  Google Scholar 

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Affiliations

  1. University of California, San Diego, USA

    Maarten J. Boom, Peter Lutz, James S. Hogan & Richard M. Peters

Authors
  1. Maarten J. Boom
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  2. Peter Lutz
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  3. James S. Hogan
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  4. Richard M. Peters
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Boom, M.J., Lutz, P., Hogan, J.S. et al. An automated method of separating patient from ventilator work on the lungs. J Clin Monit Comput 5, 235–242 (1988). https://doi.org/10.1007/BF02915913

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  • DOI: https://doi.org/10.1007/BF02915913

Keywords

  • Airway Pressure
  • Inspiratory Flow
  • Transpulmonary Pressure
  • Esophageal Pressure
  • Flail Chest