Manual compression of the abdomen to assess expiratory flow limitation during mechanical ventilation

• Published in: Journal of critical care 2012-02, Vol.27 (1), p.37-44
• Main Authors: Lemyze, Malcolm, MD, Favory, Raphael, MD, Alves, Isabelle, MD, Perez, Thierry, MD, Mathieu, Daniel, Pr
• Format: Article
• Language: English
• Subjects: Abdomen; Abdominal Wall; Adult; Aged; Aged, 80 and over; Anesthesia; Asthma; Chronic obstructive pulmonary disease; Critical Care; Critical Care - methods; Disease; Dynamic pulmonary hyperinflation; Expiratory flow limitation; Family medical history; Female; Forced Expiratory Flow Rates; Forced Expiratory Volume; Hospitals; Humans; Intrinsic positive end-expiratory pressure; Lung Diseases, Obstructive - physiopathology; Lungs; Male; Mechanical ventilation; Middle Aged; Point-of-Care Systems; Pressure; Prospective Studies; Reproducibility of Results; Respiration, Artificial; Respiratory system; Young Adult
• ISSN: 0883-9441; 1557-8615
• DOI: 10.1016/j.jcrc.2011.05.011

Abstract Purpose The aim of this study was to evaluate the manual compression of the abdomen (MCA) during expiration as a simple bedside method to detect expiratory flow limitation (EFL) during daily clinical practice of mechanical ventilation (MV). Methods We studied 44 semirecumbent intubated and sedated critically ill patients. Flow-volume loops obtained during MCA were superimposed upon the preceding breaths and recorded with the ventilator. Expiratory flow limitation was expressed as percentage of expiratory tidal volume without any increase in flow during MCA (MCA [%VT ]). In the first 13 patients, MCA was validated by comparison with the negative expiratory pressure (NEP) technique. Esophageal pressure changes during MCA and intrinsic positive end-expiratory pressure were also recorded in all the patients. Results Manual compression of the abdomen and NEP agreed in all cases in detecting EFL with a bias of −0.16%. Percentage of expiratory tidal volume without any increase in flow during MCA is highly correlated with percentage of expiratory tidal volume without any increase in flow during NEP (n = 13, P < .0001, r2 = 0.99) and intrinsic positive end-expiratory pressure (n = 44, P < .001, r2 = 0.78), with a good repeatability (n = 44; within-subject SD, 5.7%) and reproducibility (n = 13; within-subject SD, 2.41%). Two third of the patients were flow limited, among whom one third had no previously known respiratory disease. Conclusions Manual compression of the abdomen provides a simple, rapid, and safe bedside reliable maneuver to detect and quantify EFL during mechanical ventilation.