Biomaterial Database

Intrinsic PEEP in patients with chronic obstructive pulmonary disease. Role of expiratory muscles. 1993

V Ninane, and J C Yernault, and A de Troyer

Chest Service, Erasme University Hospital, Brussels, Belgium.

Many patients with severe chronic obstructive pulmonary disease (COPD) contract the transversus abdominis (TA) muscle during expiration. The mechanical correlates of this contraction, however, are uncertain. In the present study, we have measured airflow, esophageal (Pes), and gastric (Pga) pressures, the anteroposterior (AP) diameter of the abdomen, and the electromyogram of the TA during resting breathing in 25 seated patients with severe COPD (FEV1 = 28 +/- 8% of predicted). Nine patients (Group I: FEV1 = 29 +/- 8% of predicted) in general had no TA activity during breathing, and 16 patients (Group II: FEV1 = 27 +/- 8% of predicted) had invariable phasic expiratory TA activity. In all patients of Group II, the decrease in abdomen AP diameter during expiration was associated with a gradual fall in Pga. In contrast, in 13 patients of Group II, the expiratory decrease in abdomen AP diameter was associated with a rise in Pga; this rise in Pga averaged 2.8 +/- 2.2 cm H2O. Furthermore, most patients had positive alveolar pressure at end-expiration, as shown by the time lag between the fall in Pes at the beginning of the inspiratory effort and the onset of inspiratory flow. However, whereas end-expiratory alveolar pressure averaged 2.4 +/- 2.2 cm H2O in Group II, it was only 0.8 +/- 0.6 cm H2O in Group I (p < 0.05). For the patient group as a whole, there was a close relationship between the rise in Pga during expiration and end-expiratory alveolar pressure (r = 0.87; p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D008173	Lung Diseases, Obstructive	Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.	Obstructive Lung Diseases,Obstructive Pulmonary Diseases,Lung Disease, Obstructive,Obstructive Lung Disease,Obstructive Pulmonary Disease,Pulmonary Disease, Obstructive,Pulmonary Diseases, Obstructive
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D011175	Positive-Pressure Respiration	A method of mechanical ventilation in which pressure is maintained to increase the volume of gas remaining in the lungs at the end of expiration, thus reducing the shunting of blood through the lungs and improving gas exchange.	Positive End-Expiratory Pressure,Positive-Pressure Ventilation,End-Expiratory Pressure, Positive,End-Expiratory Pressures, Positive,Positive End Expiratory Pressure,Positive End-Expiratory Pressures,Positive Pressure Respiration,Positive Pressure Ventilation,Positive-Pressure Respirations,Positive-Pressure Ventilations,Pressure, Positive End-Expiratory,Pressures, Positive End-Expiratory,Respiration, Positive-Pressure,Respirations, Positive-Pressure,Ventilation, Positive-Pressure,Ventilations, Positive-Pressure
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D012132	Respiratory Muscles	These include the muscles of the DIAPHRAGM and the INTERCOSTAL MUSCLES.	Ventilatory Muscles,Respiratory Muscle,Muscle, Respiratory,Muscle, Ventilatory,Muscles, Respiratory,Muscles, Ventilatory,Ventilatory Muscle
D004567	Electrodes, Implanted	Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.	Implantable Electrodes,Implantable Stimulation Electrodes,Implanted Electrodes,Implanted Stimulation Electrodes,Electrode, Implantable,Electrode, Implantable Stimulation,Electrode, Implanted,Electrode, Implanted Stimulation,Electrodes, Implantable,Electrodes, Implantable Stimulation,Electrodes, Implanted Stimulation,Implantable Electrode,Implantable Stimulation Electrode,Implanted Electrode,Implanted Stimulation Electrode,Stimulation Electrode, Implantable,Stimulation Electrode, Implanted,Stimulation Electrodes, Implantable,Stimulation Electrodes, Implanted
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D005260	Female		Females