HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Respond to This Article Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Take the CE Test Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Frazier, S. K. Articles by Brom, H. Search for Related Content PubMed PubMed Citation Articles by Frazier, S. K. Articles by Brom, H.

CE Article

Hemodynamic Changes During Discontinuation of Mechanical Ventilation in Medical Intensive Care Unit Patients

Corresponding author: Susan K. Frazier, RN, PhD, Associate Professor, University of Kentucky College of Nursing, 523 CON Bldg, Lexington, KY 40536-0232 (e-mail: skfraz2{at}email.uky.edu).

• Background Cardiac dysfunction can prevent successful discontinuation of mechanical ventilation. Critically ill patients may have undetected cardiac disease, and cardiac dysfunction can be produced or exacerbated by underlying pathophysiology.

• Objective To describe and compare hemodynamic function and cardiac rhythm during baseline mechanical ventilation with function and rhythm during a trial of continuous positive airway pressure in medical intensive care patients.

• Methods A convenience sample of 43 patients (53% men; mean age 51.1 years) who required mechanical ventilation were recruited for this pilot study. Cardiac output, stroke volume, arterial blood pressure, heart rate, cardiac rhythm, and plasma catecholamine levels were measured during mechanical ventilation and during a trial of continuous positive airway pressure.

• Results One third of the patients had difficulty discontinuing mechanical ventilation. Successful patients had significantly increased cardiac output and stroke volume without changes in heart rate or arterial pressure during the trial of continuous positive airway pressure. Unsuccessful patients had no significant changes in cardiac output, stroke volume, or heart rate but had a significant increase in mean arterial pressure. The 2 groups of patients also had different patterns in ectopy. Concurrently, catecholamine concentrations decreased in the successful patients and significantly increased in the unsuccessful patients during the trial.

• Conclusions Patterns of cardiac function and plasma catecholamine levels differed between patients who did or did not achieve spontaneous ventilation with a trial of continuous positive airway pressure. Cardiac function must be systematically considered before and during the return to spontaneous ventilation to optimize the likelihood of success.

Notice to CE enrollees: A closed-book, multiple-choice examination following this article tests your understanding of the following objectives: Describe the hemodynamic alterations induced by discontinuation of mechanical ventilation. Recognize the significant influence cardiovascular function may have on the success of ventilator discontinuation. Understand the patterns of cardiac response during weaning trials. To read this article and take the CE test online, visit www.ajcconline.org and click "CE Articles in This Issue."

This article has been cited by other articles:

				S. K. Frazier, D. K. Moser, R. Schlanger, J. Widener, L. Pender, and K. S. Stone Autonomic Tone in Medical Intensive Care Patients Receiving Mechanical Ventilation and During a CPAP Weaning Trial Biol Res Nurs, April 1, 2008; 9(4): 301 - 310. [Abstract] [PDF]