Alveolar Pressure, Pulmonary Venous Pressure, and the Vascular Waterfall

Permutt, Solbert; Bromberger-Barnea, B.; Bane, Harry N.

doi:10.1159/000192224

Cited by 135 publications

(68 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In fact the curves are remarkably similar by those obtained by Permutt et al (1962) in experiments on dog lungs and an example is shown in Fig. 2B.…”

Section: Zone 2-supporting

confidence: 84%

“…The Zone 2 behavior is sometimes compared with that of a Starling resistor, which is a collapsible thin-walled rubber tube in a pressure chamber, because the flow in such a device is independent of the downstream pressure when the chamber pressure exceeds this pressure (Permutt et al, 1962). The conventional explanation for the lung is that the thin-walled capillaries collapse at their downstream ends and thus limit flow.…”

Section: Zone 2-mentioning

confidence: 99%

See 1 more Smart Citation

Major differences in the pulmonary circulation between birds and mammals

West

Watson

2007

Respiratory Physiology & Neurobiology

View full text Add to dashboard Cite

The lungs of domestic chickens were perfused with blood or dextran/saline and the pulmonary artery pressure (Pa) and venous pressure (Pv) were varied in relation to air capillary pressure (PA). In zone 3 conditions, pulmonary vascular resistance (PVR) was virtually unchanged with increases in either Pa or Pv. This is very different from mammals where the same interventions greatly reduce PVR. In zone 2 conditions blood flow was essentially independent of Pv as in mammalian lungs but all the capillaries appeared to be open, apparently incompatible with a Starling resistor mechanism. In zone 1 the capillaries were open even when PA exceeded Pa by over 30 cmH 2 O which is very different behavior from that of the mammalian lung. We conclude that the air capillaries that surround the blood capillaries provide rigid support in both compression and expansion of the vessels. The work suggests a pathogenesis for Pulmonary Hypertension Syndrome in chickens which costs the broiler industry $1 billion per year.

show abstract

“…In fact the curves are remarkably similar by those obtained by Permutt et al (1962) in experiments on dog lungs and an example is shown in Fig. 2B.…”

Section: Zone 2-supporting

confidence: 84%

Section: Zone 2-mentioning

confidence: 99%

Major differences in the pulmonary circulation between birds and mammals

West

Watson

2007

Respiratory Physiology & Neurobiology

View full text Add to dashboard Cite

show abstract

“…This understanding is based upon the analogy of the steady flow through a vascular system with the flow through an elastic tube (see for details, Guyton [7], Brecher [8], Banister and Torrance [9] and Permutt et al [10]). Such a tube is named a Starling resistor because of its introduction as a laboratory device for simulating the resistance of the vascular system (see Knowlton and Starling [11]).…”

Section: Introductionmentioning

confidence: 99%

Mathematical model for a Herschel-Bulkley fluid flow in an elastic tube

et al. 2011

View full text Add to dashboard Cite

Abstract:The constitution of blood demands a yield stress fluid model, and among the available yield stress fluid models for blood flow, the Herschel-Bulkley model is preferred (because Bingham, Power-law and Newtonian models are its special cases). The Herschel-Bulkley fluid model has two parameters, namely the yield stress and the power law index. The expressions for velocity, plug flow velocity, wall shear stress, and the flux flow rate are derived. The flux is determined as a function of inlet, outlet and external pressures, yield stress, and the elastic property of the tube. Further when the power-law index = 1 and the yield stress τ 0 → 0, our results agree well with those of Rubinow and Keller [J. Theor. Biol. 35, 299 (1972)]. Furthermore, it is observed that, the yield stress and the elastic parameters ( 1 and 2 ) have strong effects on the flux of the non-Newtonian fluid flow in the elastic tube. The results obtained for the flow characteristics reveal many interesting behaviors that warrant further study on the non-Newtonian fluid flow phenomena, especially the shear-thinning phenomena. Shear thinning reduces the wall shear stress.

show abstract

“…Permutt et al (Permutt et al, 1962) proposed that if P A remains constant, there would be three regions within the lung in which P a and P v vary according to the vertical level in the lung. When P A > P a > P v there is no flow because the capillary is collapsed.…”

Section: The Zonal Modelmentioning

confidence: 99%

Gas Exchange in the Normal Lung : Experimental studies on the effects of positive end-expiratory pressure and body position

Johansson¹

2014

Linköping University Medical Dissertations

View full text Add to dashboard Cite

BACKGROUND:The principal function of the lung is gas exchange requiring adequate ventilation and perfusion at the level of the alveoli. The efficiency of gas exchange is depending on the distributions of regional ventilation (V) and pulmonary blood flow (Q) and their correlation. AIMS:To validate a high-resolution method to quantify regional V and to investigate the Radioactive microspheres, 15 m in diameter, were used for determining regional Q. Nitric oxide synthase (NOS) was inhibited with Nω-nitro-L-arginine methyl ester (L-NAME) to evaluate the role of NO on regional V/Q matching. The right lung was dried at total lung capacity and diced in approx. 1000 regions tracking the spatial location of each region. CONCLUSION: There were marked differences in redistribution of regional ventilation and regional pulmonary blood flow between prone and supine position when PEEP was applied. RESULTS:NO was not an active mechanism for V/Q matching in normal sheep lungs. VII List of original papershis thesis is based on the following four papers, which will be referred to by their Roman numerals: I.Positive end-expiratory pressure affects regional redistribution of ventilation differently in prone and supine sheep.

show abstract

Alveolar Pressure, Pulmonary Venous Pressure, and the Vascular Waterfall

Cited by 135 publications

References 6 publications

Major differences in the pulmonary circulation between birds and mammals

Major differences in the pulmonary circulation between birds and mammals

Mathematical model for a Herschel-Bulkley fluid flow in an elastic tube

Gas Exchange in the Normal Lung : Experimental studies on the effects of positive end-expiratory pressure and body position

Contact Info

Product

Resources

About