Biomaterial Database

Hemodynamics and intrathoracic pressure transmission during controlled mechanical ventilation and positive end-expiratory pressure in normal and low compliant lungs. 1988

B Venus, and L E Cohen, and R A Smith

Department of Critical Care Medicine, Memorial Medical Center of Jacksonville, FL 32216.

PEEP can significantly reduce cardiac output. This reduction in cardiac output is frequently attributed to transmission of airway pressure to intrathoracic vascular structures. We designed an acute lung injury (ALI) model in swine (n = 7) characterized by low lung thorax compliance (CLT) and compared the fractional transmission of airway pressure to pleura (PPL) and pericardium (PPC) and hemodynamics to normal animals (n = 5) during controlled mechanical ventilation (CMV) and PEEP. Fractional transmission of PEEP to PPL and PPC was reduced significantly from 62 +/- 8% and 54 +/- 19 (SD)% to 34 +/- 7% and 36 +/- 9% in normal and ALI animals, respectively. End-inspiration tracheal pressure was significantly higher in the low compliant group; thus, cardiac output was equally depressed in both groups despite reduction in fractional airway pressure transmission in ALI animals, possibly because absolute inspiratory PPL and PPC were similar due to increased pressure required to inflate injured lungs. The results of this investigation do not support the presumption that low CLT blunts hemodynamic consequences of CMV and PEEP.

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
D008297	Male		Males
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
D012115	Residual Volume	The volume of air remaining in the LUNGS at the end of a maximal expiration. Common abbreviation is RV.	Residual Volumes,Volume, Residual,Volumes, Residual
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
D002302	Cardiac Output	The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).	Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D005260	Female		Females
D006439	Hemodynamics	The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.	Hemodynamic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog