Annals
Established in 1927 by the American College of Physicians
:
Advanced search
 
box Article
 arrow  Table of Contents                
space
 arrow  Full Text of this article Free
space
 arrow  Figures/Tables List
space
box Services
 arrow  Send comment/rapid response letter
space
 arrow  Notify a friend about this article
space
 arrow  Alert me when this article is cited
space
 arrow  Add to Personal Archive
space
 arrow  Download to Citation Manager
space
 arrow  ACP Search                        
space
 arrow  Get Permissions
space
box Google Scholar
 arrow  Search for Related Content
space
box PubMed
Articles in PubMed by Author:
  arrow  Mohsenifar, Z.
space
  arrow  Koerner, S. K.
space
 arrow  Related Articles in PubMed
space
 arrow  PubMed Citation
space
 arrow  PubMed
space

ARTICLE

Gastric Intramural pH as a Predictor of Success or Failure in Weaning Patients from Mechanical Ventilation

right arrow Z. Mohsenifar; Angela Hay; Jeffrey Hay; Michael I. Lewis; and Spencer K. Koerner

15 October 1993 | Volume 119 Issue 8 | Pages 794-798

Objective: To determine whether gastric intramural pH (pHi), an indirect measure of gastric mucosal ischemia, can be used to predict the success of weaning from mechanical ventilation. Gastric mucosal ischemia (and, therefore, acidosis) may develop in patients during unsuccessful attempts to wean them from mechanical ventilation because blood flow from nonvital areas (for example, splanchnic bed) is diverted to meet the increased demands of respiratory muscles.

Design: Cohort study.

Setting: Intensive care unit.

Patients: Twenty-nine patients receiving assisted mechanical ventilation for respiratory failure who were thought by their physicians to be weanable from mechanical ventilation.

Measurements: Simultaneous samples of arterial blood and gastric juice were obtained from patients during assisted mechanical ventilation, as well as during weaning trials. The predictor variable, pHi, was calculated using the following equation: 6.1 + log HCO3/(gastric PCO2 x 0.0307). The outcome was success or failure of weaning, decided by physicians blinded to the study.

Results: Patients who could not be weaned from mechanical ventilation had a substantially reduced gastric pHi (7.36 during mechanical ventilation compared with 7.09 during weaning [difference, 0.27; 95% CI, 0.12 to 0.42; P < 0.01]). Patients who were successfully weaned from mechanical ventilation showed no change in pHi (7.45 during mechanical ventilation compared with 7.46 during weaning [difference, 0.01; CI, –0.01 to 0.03; P = 0.29]). The sensitivity and specificity of pHi in predicting weaning success or failure were both 100% (CI, 81 to 100 and 72 to 100, respectively).

Conclusion: Gastrointestinal acidosis may be an early sign of weaning failure. Measurement of pHi, which is simple and rapid, may be of practical value in predicting the likelihood of weaning success or failure during weaning trials.

Author and Article Information
space

From Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California.
Requests for Reprints: Z. Mohsenifar, MD, Cedars-Sinai Medical Center, UCLA School of Medicine, 8700 Beverly Boulevard Pulmonary Division, Room 6732, Los Angeles, CA 90048.




This article has been cited by other articles:


Home page
Eur Respir JHome page
J-M. Boles, J. Bion, A. Connors, M. Herridge, B. Marsh, C. Melot, R. Pearl, H. Silverman, M. Stanchina, A. Vieillard-Baron, et al.
Weaning from mechanical ventilation
Eur. Respir. J., May 1, 2007; 29(5): 1033 - 1056.
[Abstract] [Full Text] [PDF]


Home page
ChestHome page
M. R. Silver
Anemia in the Long-term Ventilator-Dependent Patient With Respiratory Failure
Chest, November 1, 2005; 128(5_suppl_2): 568S - 575S.
[Abstract] [Full Text] [PDF]


Home page
ChestHome page
M. R. Pinsky
Cardiovascular Issues in Respiratory Care
Chest, November 1, 2005; 128(5_suppl_2): 592S - 597S.
[Abstract] [Full Text] [PDF]


Home page
Am J Crit CareHome page
R. Twibell, D. Siela, and M. Mahmoodi
Subjective Perceptions and Physiological Variables During Weaning From Mechanical Ventilation
Am. J. Crit. Care., March 1, 2003; 12(2): 101 - 112.
[Abstract] [Full Text] [PDF]


Home page
ChestHome page
N. R. MacIntyre
Evidence-Based Guidelines for Weaning and Discontinuing Ventilatory Support : A Collective Task Force Facilitated by the American College of Chest Physicians; the American Association for Respiratory Care; and the American College of Critical Care Medicine
Chest, December 1, 2001; 120(6_suppl): 375S - 396S.
[Abstract] [Full Text] [PDF]


Home page
ChestHome page
M. Meade, G. Guyatt, D. Cook, L. Griffith, T. Sinuff, C. Kergl, J. Mancebo, A. Esteban, and S. Epstein
Predicting Success in Weaning From Mechanical Ventilation
Chest, December 1, 2001; 120(6_suppl): 400S - 424S.
[Abstract] [Full Text] [PDF]


Home page
ChestHome page
P. C. Hebert, M. A. Blajchman, D. J. Cook, E. Yetisir, G. Wells, J. Marshall, and I. Schweitzer
Do Blood Transfusions Improve Outcomes Related to Mechanical Ventilation?
Chest, June 1, 2001; 119(6): 1850 - 1857.
[Abstract] [Full Text] [PDF]


Home page
Med Decis MakingHome page
A. Gottschalk, M. C. Hyzer, and R. T. Geer
A Comparison of Human and Machine-based Predictions of Successful Weaning from Mechanical Ventilation
Med Decis Making, April 1, 2000; 20(2): 160 - 169.
[Abstract] [PDF]


Home page
Am. J. Respir. Crit. Care Med.Home page
A. MALDONADO, T. T. BAUER, M. FERRER, C. HERNANDEZ, F. ARANCIBIA, R. RODRIGUEZ-ROISIN, and A. TORRES
Capnometric Recirculation Gas Tonometry and Weaning from Mechanical Ventilation
Am. J. Respir. Crit. Care Med., January 1, 2000; 161(1): 171 - 176.
[Abstract] [Full Text]


Home page
Am. J. Respir. Crit. Care Med.Home page
N. BOCQUILLON, D. MATHIEU, R. NEVIERE, N. LEFEBVRE, X. MARECHAL, and F. WATTEL
Gastric Mucosal pH and Blood Flow during Weaning from Mechanical Ventilation in Patients with Chronic Obstructive Pulmonary Disease
Am. J. Respir. Crit. Care Med., November 1, 1999; 160(5): 1555 - 1561.
[Abstract] [Full Text]


Home page
J. Appl. Physiol.Home page
J. A. Guzman and J. A. Kruse
Splanchnic hemodynamics and gut mucosal-arterial PCO2 gradient during systemic hypocapnia
J Appl Physiol, September 1, 1999; 87(3): 1102 - 1106.
[Abstract] [Full Text] [PDF]


Home page
Arch. Dis. Child. Fetal Neonatal Ed.Home page
M. E Campbell, J. E Van Aerde, P.-Y. Cheung, and D. C Mayes
Tonometry to estimate intestinal perfusion in newborn piglets
Arch. Dis. Child. Fetal Neonatal Ed., September 1, 1999; 81(2): 105F - 109.
[Abstract] [Full Text]


Home page
ChestHome page
B. Afessa, L. Hogans, and R. Murphy
Predicting 3-Day and 7-Day Outcomes of Weaning From Mechanical Ventilation
Chest, August 1, 1999; 116(2): 456 - 461.
[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
K. R. Walley, B. P. Friesen, M. F. Humer, and P. T. Phang
Small bowel tonometry is more accurate than gastric tonometry in detecting gut ischemia
J Appl Physiol, November 1, 1998; 85(5): 1770 - 1777.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Respir. Crit. Care Med.Home page
A. ESTEBAN, I. ALÍA, F. GORDO, R. FERNÁNDEZ, J. F. SOLSONA, I. VALLVERDÚ, S. MACÍAS, J. M. ALLEGUE, J. BLANCO, D. CARRIEDO, et al.
Extubation Outcome after Spontaneous Breathing Trials with T-Tube or Pressure Support Ventilation
Am. J. Respir. Crit. Care Med., July 1, 1997; 156(2): 459 - 465.
[Abstract] [Full Text]


Home page
NEJMHome page
E. W. Ely, A. M. Baker, D. P. Dunagan, H. L. Burke, A. C. Smith, P. T. Kelly, M. M. Johnson, R. W. Browder, D. L. Bowton, and E. F. Haponik
Effect on the Duration of Mechanical Ventilation of Identifying Patients Capable of Breathing Spontaneously
N. Engl. J. Med., December 19, 1996; 335(25): 1864 - 1869.
[Abstract] [Full Text] [PDF]


Home page
JWatch GeneralHome page
GASTRIC INTRAMURAL pH AND VENTILATOR WEANING
Journal Watch (General), November 2, 1993; 1993(1102): 8 - 8.
[Full Text]




 Home | Current Issue | Past Issues | In the Clinic | ACP Journal Club | CME | Collections | Audio/Video | Mobile | Subscribe | Tools | Help | ACP Online 

Copyright © 1993 by the American College of Physicians.