Biomaterial Database

Positive end-expiratory pressure and lung compliance: effect on delivered tidal volume. 1995

P H Pan, and J J van der Aa

Department of Anesthesiology, University of Florida College of Medicine, Gainesville 32610-0254, USA.

The effects of positive end-expiratory pressure (PEEP) and lung compliance (CL) on delivered tidal volume (VTdel) and ventilator output were evaluated in the following anaesthesia machine/ventilator systems: Narkomed III with a Model AV-E ventilator (III/AV-E system) and an Ohmeda Modulus II with either a 7810 anaesthesia ventilator (II/7810 system) or a Model 7000 anaesthesia ventilator (II/7000 system). With a standard circle anaesthesia breathing circuit connected to a test lung simulating CL, gas flow was measured and integrated over time at each combination of VT settings (VTset), 500 ml or 1000 ml; CL settings, 0.15 to 0.01 L.cm H2O-1 decreased incrementally; and PEEP settings, 0 to 30 cm H2O increased in 5-cm H2O increments. The integral of gas flow at the Y-piece of the breathing circuit was recorded as VTdel and at the output of the ventilator bellows as ventilator output. As CL decreased to 0.01 L.cm H2O-1 and PEEP increased to 30 cm H2O, at VTset of 500 ml and 1000 ml, respective VTdel decreased linearly to 251 +/- 6 ml and 542 +/- 7 with the III/AV-E, 201 +/- 5 and 439 +/- 5, with the II/7810, and 181 +/- 4 and 433 +/- 7 ml with the II/7000 (P < 0.05 among the three systems). Loss in VTdel due to PEEP alone, which increased only slightly when VTset was increased, accounted for an increasingly greater percentage of VTset as it was decreased, which was less pronounced with low CL.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D008170	Lung Compliance	The capability of the LUNGS to distend under pressure as measured by pulmonary volume change per unit pressure change. While not a complete description of the pressure-volume properties of the lung, it is nevertheless useful in practice as a measure of the comparative stiffness of the lung. (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p562)	Compliance, Lung,Compliances, Lung,Lung Compliances
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
D012121	Respiration, Artificial	Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).	Ventilation, Mechanical,Mechanical Ventilation,Artificial Respiration,Artificial Respirations,Mechanical Ventilations,Respirations, Artificial,Ventilations, Mechanical
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000776	Anesthesiology	A specialty concerned with the study of anesthetics and anesthesia.