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R L Scott

Publications and source records attributed to R L Scott.

At least 73 records · Page 4Linked to original sources
PubMed1982

A feedback system to control blood flow in dog lung lobes.

We have developed an electromechanical feedback system to control blood flow to the lower left lung lobe of dogs. Blood flow is measured with an electromagnetic flowmeter. The feedback system compares the blood flow signal to an adjustable reference voltage and causes a motor to turn. The direction of motor rotation depends on the relative magnitude of the flow signal and the reference. The motor pushes the plunger of a syringe that is attached to a balloon in the right pulmonary artery. Inflation of the balloon causes increased blood flow to the lower left lobe. We have used the system to control lobe blood flow in three dogs.

Animals↗
PubMed1982

Effect of outflow pressure upon lymph flow from dog lungs.

The pulmonary lymph flow rate (QL) should be a function of the lymph vessels' resistance and the pressure gradient along the vessels. We attempted to study how these factors affect lymph flow. We assumed that the lymph system could be represented by a single pressure generated within the lung (PL) and a single resistance (RL). Thus, QL should be a function of the lymph vessel outflow pressure (Po): QL = (PL - Po)/RL. We cannulated tracheobronchial lymph vessels in eight anesthetized dogs and varied Po by raising the outflow end of the cannula. QL decreased linearly when we increased Po. We estimated RL as - delta Po/ delta QL and PL as the extrapolated Po at which QL = 0. At baseline PL = 7.7 +/- 2.7 (SD) cm H2O and RL = 0.36 +/- 0.25 cm H2O. min/microliters. After we increased capillary pressure to produce edema, PL and RL averaged 22.8 +/- 8.8 and 0.14 +/- 0.12, respectively. After we reduced the capillary pressure to baseline in the edematous lungs, PL and RL averaged 11.6 +/- 2.8 and 0.08 +/- 0.09, respectively. All changes in PL and RL were significant (P less than 0.05). These results show that (1) lymph flow rate depends upon lymph vessel outflow pressure, and (2) the QL vs. Po relationship is changed by edema. PL may be equal to the pressure causing lymph to flow and RL may equal the lymph vessel resistance.

Animals↗
PubMed1982

Massive transfusion.

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2,3-Diphosphoglycerate↗
PubMed1980

Errors in calculated oncotic pressure of dog plasma.

Several equations to calculate plasma oncotic pressure (pi) from the total protein concentration (C) have been previously described. These equations were derived empirically from samples with a wide range of C obtained by diluting or concentrating normal plasma samples. To test these equations over a range of naturally occurring C, we measured C and pi of plasma samples from 40 dogs. C ranged from 5.3 to 8.7 g/dl and averaged 6.5 +/- 0.1 (mean +/- SE) and pi averaged 17.9 +/- 0.3 mmHg. The regression equation was pi = 78.14 + 1.67 C (r = 0.74). pi increased with C much less than predicted with the commonly used equations. The albumin-to-globulin concentration ratios (A/G), determined in 27 of the dogs, decreased with increasing C (A/G = 1.56-0.128 C, r = 0.62). The lower A/G at the higher C's could cause the lower than predicted increase in pi with C, because the equations were developed from data in which A/G was constant.

Animals↗