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Effects of positive end-expiratory pressure and body position on pressure in the thoracic great veins.
Am Rev Respir Dis. 1993 Dec; 148(6 Pt 1):1657-64.AR

Abstract

Positive end-expiratory pressure (PEEP) commonly decreases cardiac output. The major cause of this is believed to be decreased venous return due to increased right atrial pressure. We hypothesized that when the lungs were hyperinflated they could also restrict venous return by directly compressing the thoracic vena cavae. We measured the longitudinal distribution of pressure in the thoracic vena cavae of 10 dogs on and off 10 mm Hg PEEP, in the supine (S), prone (P), right lateral (RL), and left lateral decubitus (LL) positions. In the superior vena cava (SVC) both on and off PEEP, and in the inferior vena cava (IVC) off PEEP, pressure fell uniformly from the thoracic inlet to the right atrium. However, in the IVC on PEEP, intravascular pressure fell abruptly by up to 5 mm Hg. This pressure drop occurred in a discrete (1 to 2-cm) segment of the IVC, suggesting a localized increased in extravascular surface pressure. When this pressure inflection was present, changes in right atrial pressure had no effect on pressure in the IVC upstream of the inflection, consistent with a "vascular waterfall." These observations were most prominent in the LL, least common in the RL, and variably present in the P and S positions. Occlusion of the right bronchus intermedius prior to PEEP (preventing right lower, middle, and accessory lobe inflation) prevented the appearance of the pressure inflection during PEEP in the LL but not in the S or P positions. We conclude that PEEP impedes venous return partly by direct compression of the IVC, predominantly in positions in which the IVC is non-dependent.(

ABSTRACT

TRUNCATED AT 250 WORDS)

Authors+Show Affiliations

Department of Medicine, Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224.No affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

8256916

Citation

Fessler, H E., et al. "Effects of Positive End-expiratory Pressure and Body Position On Pressure in the Thoracic Great Veins." The American Review of Respiratory Disease, vol. 148, no. 6 Pt 1, 1993, pp. 1657-64.
Fessler HE, Brower RG, Shapiro EP, et al. Effects of positive end-expiratory pressure and body position on pressure in the thoracic great veins. Am Rev Respir Dis. 1993;148(6 Pt 1):1657-64.
Fessler, H. E., Brower, R. G., Shapiro, E. P., & Permutt, S. (1993). Effects of positive end-expiratory pressure and body position on pressure in the thoracic great veins. The American Review of Respiratory Disease, 148(6 Pt 1), 1657-64.
Fessler HE, et al. Effects of Positive End-expiratory Pressure and Body Position On Pressure in the Thoracic Great Veins. Am Rev Respir Dis. 1993;148(6 Pt 1):1657-64. PubMed PMID: 8256916.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Effects of positive end-expiratory pressure and body position on pressure in the thoracic great veins. AU - Fessler,H E, AU - Brower,R G, AU - Shapiro,E P, AU - Permutt,S, PY - 1993/12/1/pubmed PY - 1993/12/1/medline PY - 1993/12/1/entrez SP - 1657 EP - 64 JF - The American review of respiratory disease JO - Am Rev Respir Dis VL - 148 IS - 6 Pt 1 N2 - Positive end-expiratory pressure (PEEP) commonly decreases cardiac output. The major cause of this is believed to be decreased venous return due to increased right atrial pressure. We hypothesized that when the lungs were hyperinflated they could also restrict venous return by directly compressing the thoracic vena cavae. We measured the longitudinal distribution of pressure in the thoracic vena cavae of 10 dogs on and off 10 mm Hg PEEP, in the supine (S), prone (P), right lateral (RL), and left lateral decubitus (LL) positions. In the superior vena cava (SVC) both on and off PEEP, and in the inferior vena cava (IVC) off PEEP, pressure fell uniformly from the thoracic inlet to the right atrium. However, in the IVC on PEEP, intravascular pressure fell abruptly by up to 5 mm Hg. This pressure drop occurred in a discrete (1 to 2-cm) segment of the IVC, suggesting a localized increased in extravascular surface pressure. When this pressure inflection was present, changes in right atrial pressure had no effect on pressure in the IVC upstream of the inflection, consistent with a "vascular waterfall." These observations were most prominent in the LL, least common in the RL, and variably present in the P and S positions. Occlusion of the right bronchus intermedius prior to PEEP (preventing right lower, middle, and accessory lobe inflation) prevented the appearance of the pressure inflection during PEEP in the LL but not in the S or P positions. We conclude that PEEP impedes venous return partly by direct compression of the IVC, predominantly in positions in which the IVC is non-dependent.(ABSTRACT TRUNCATED AT 250 WORDS) SN - 0003-0805 UR - https://www.unboundmedicine.com/medline/citation/8256916/Effects_of_positive_end-expiratory_pressure_and_body_position_on_pressure_in_the_thoracic_great_veins. L2 - https://www.atsjournals.org/doi/10.1164/ajrccm/148.6_Pt_1.1657?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -