scholarly journals Organs Blood Flow during Elevation of Body Temperature in Sevoflurane Anesthetized Rats

2017 ◽  
Vol 2017 ◽  
pp. 1-7
Author(s):  
Koichi Shimo ◽  
Ko Takakura ◽  
Kenji Shigemi
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Body Temperature ◽  
Arterial Blood Pressure ◽  
Pulse Rate ◽  
Organ Blood Flow ◽  
Aortic Blood Flow ◽  
Sevoflurane Anesthesia ◽  
Arterial Blood ◽  
Small Intestinal

The aim of this study is to investigate how elevation of body temperature changes organs blood flow during sevoflurane anesthesia. We conducted in vivo research on 14 male Wistar rats to monitor pulse rate and arterial blood pressure and measure hepatic, small intestinal, renal, and descending aortic blood flow using a laser Doppler blood flowmeter. We assessed the changes in organ blood flow, pulse rate, and arterial blood pressure during elevation of the rats’ body temperatures up to 41.5°C under anesthesia with 2.0% or 3.0% sevoflurane. We concluded that elevation of body temperature up to 39.5°C does not change hepatic, small intestinal, and renal blood flow during 2.0 and 3.0% sevoflurane anesthesia.

Forearm and finger blood flow responses to passive body tilts

1979 ◽  
Vol 46 (2) ◽  
pp. 288-292 ◽  
Author(s):  
Y. A. Mengesha ◽  
G. H. Bell
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Arterial Blood Pressure ◽  
Vascular Resistance ◽  
Pulse Rate ◽  
Forearm Blood Flow ◽  
Body Tilt ◽  
Finger Blood Flow ◽  
Arterial Blood ◽  
Forearm Vascular Resistance

Ten to fifteen healthy subjects, ages 18--30 yr, were used to assess the correlation of forearm blood flow with graded passive body tilts and vascular resistance and also to discern the relative effects of body tilts on finger blood flow. In the head-up tilts forearm blood flow and arterial blood pressure fell progressively, whereas forearm vascular resistance and pulse rate increased. In the head-down tilts the forearm blood flow and the arterial blood pressure increased, whereas the forearm vascular resistance and pulse rate decreased. These changes were found to be significantly correlated with the different tilt angles and with one another. In a preliminary study it was found that infrared heating of the carpometacarpal region produced finger vasodilatation similar to the forearm vasodilatation observed by Crockford and Hellon (6). However, unlike forearm blood flow, finger blood flow showed no appreciable response to either the head-up or head-down tilts. This indicates that the sympathetic tone and the volume of blood in the finger are not appreciably altered by this test procedure at least 1 min after the body tilt is assumed.

Effect of vasopressors on organ blood flow during endotoxin shock in pigs

1987 ◽  
Vol 252 (2) ◽  
pp. H291-H300 ◽  
Author(s):  
M. J. Breslow ◽  
C. F. Miller ◽  
S. D. Parker ◽  
A. T. Walman ◽  
R. J. Traystman
Keyword(s):  
Blood Pressure ◽  
Skeletal Muscle ◽  
Blood Flow ◽  
Left Ventricle ◽  
Arterial Blood Pressure ◽  
Endotoxin Shock ◽  
Organ Blood Flow ◽  
Shock Model ◽  
Blood Pressure Elevation ◽  
Arterial Blood

A volume-resuscitated porcine endotoxin shock model was used to evaluate the effect on organ blood flow of increasing systemic arterial blood pressure with vasopressors. Administration of 0.05–0.2 mg/kg of Escherichia coli endotoxin (E) reduced mean arterial blood pressure (MAP) to 50 mmHg, decreased systemic vascular resistance to 50% of control, and did not change cardiac output or heart rate. Blood flow to brain, kidney, spleen, and skeletal muscle was reduced during endotoxin shock, but blood flow to left ventricle, small and large intestine, and stomach remained at pre-endotoxin levels throughout the study period. Four groups of animals were used to evaluate the effect of vasopressor therapy. A control group received E and no vasopressor, whereas the other three groups received either norepinephrine, dopamine, or phenylephrine. Vasopressors were administered starting 60 min after E exposure, and the dose of each was titrated to increase MAP to 75 mmHg. Despite the increase in MAP, brain blood flow did not increase in any group. Norepinephrine alone increased blood flow to the left ventricle. Kidney, splanchnic, and skeletal muscle blood flow did not change with vasopressor administration. The dose of norepinephrine required to increase MAP by 20–25 mmHg during E shock was 30 times the dose required for a similar increase in MAP in animals not receiving E. We conclude that hypotension in the fluid resuscitated porcine E shock model is primarily the result of peripheral vasodilatation, that the vascular response to vasoconstrictors in this model is markedly attenuated following E administration, that blood pressure elevation with norepinephrine, dopamine, and phenylephrine neither decreases blood flow to any organ nor increases blood flow to organs with reduced flow, and that norepinephrine, dopamine, and phenylephrine affect regional blood flow similarly in this model.

scholarly journals Estimation of changes in instantaneous aortic blood flow by the analysis of arterial blood pressure

2012 ◽  
Vol 112 (11) ◽  
pp. 1832-1838 ◽  
Author(s):  
Tatsuya Arai ◽  
Kichang Lee ◽  
Robert P. Marini ◽  
Richard J. Cohen
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Arterial Blood Pressure ◽  
Aortic Blood Flow ◽  
Windkessel Model ◽  
Arx Model ◽  
Arterial Blood ◽  
Aortic Blood

The purpose of this study was to introduce and validate a new algorithm to estimate instantaneous aortic blood flow (ABF) by mathematical analysis of arterial blood pressure (ABP) waveforms. The algorithm is based on an autoregressive with exogenous input (ARX) model. We applied this algorithm to diastolic ABP waveforms to estimate the autoregressive model coefficients by requiring the estimated diastolic flow to be zero. The algorithm incorporating the coefficients was then applied to the entire ABP signal to estimate ABF. The algorithm was applied to six Yorkshire swine data sets over a wide range of physiological conditions for validation. Quantitative measures of waveform shape (standard deviation, skewness, and kurtosis), as well as stroke volume and cardiac output from the estimated ABF, were computed. Values of these measures were compared with those obtained from ABF waveforms recorded using a Transonic aortic flow probe placed around the aortic root. The estimation errors were compared with those obtained using a windkessel model. The ARX model algorithm achieved significantly lower errors in the waveform measures, stroke volume, and cardiac output than those obtained using the windkessel model ( P < 0.05).

Distribution of respiratory muscle and organ blood flow during endotoxic shock in dogs

1985 ◽  
Vol 59 (6) ◽  
pp. 1802-1808 ◽  
Author(s):  
S. N. Hussain ◽  
C. Roussos
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cardiac Output ◽  
Arterial Blood Pressure ◽  
Respiratory Muscle ◽  
Muscle Blood Flow ◽  
Endotoxic Shock ◽  
Organ Blood Flow ◽  
Similar Reduction ◽  
Arterial Blood

Respiratory muscle blood flow and organ blood flow during endotoxic shock were studied in spontaneously breathing dogs (SB, n = 6) and mechanically ventilated dogs (MV, n = 5) with radiolabeled microspheres. Shock was produced by a 5-min intravenous injection of Escherichia coli endotoxin (0.55:B5, Difco, 10 mg/kg) suspended in saline. Mean arterial blood pressure and cardiac output in the SB group dropped to 59 and 45% of control values, respectively. There was a similar reduction in arterial blood pressure and cardiac output in the MV group. Total respiratory muscle blood flow in the SB group increased significantly from the control value of 51 +/- 4 ml/min (mean +/- SE) to 101 +/- 22 ml/min at 60 min of shock. In the MV group, respiratory muscle perfusion fell from control values of 43 +/- 12 ml/min to 25 +/- 3 ml/min at 60 min of shock. In the SB group, 8.8% of the cardiac output was received by the respiratory muscle during shock in comparison with 1.9% in the MV group. In both groups of dogs, blood flow to most organs was compromised during shock; however, blood flow to the brain, gut, and skeletal muscles was higher in the MV group than in the SB group. Thus by mechanical ventilation a fraction of the cardiac output used by the working respiratory muscles can be made available for perfusion of other organs during endotoxic shock.

Effect of naloxone and ibuprofen on organ blood flow during endotoxic shock in pig

1988 ◽  
Vol 255 (1) ◽  
pp. H177-H184 ◽  
Author(s):  
M. K. Nishijima ◽  
M. J. Breslow ◽  
C. F. Miller ◽  
R. J. Traystman
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Arterial Blood Pressure ◽  
Mean Arterial Blood Pressure ◽  
Regional Blood Flow ◽  
Endotoxic Shock ◽  
Organ Blood Flow ◽  
Group Iii ◽  
Arterial Blood ◽  
Group I

The effects of an opiate antagonist naloxone and a cyclooxygenase inhibitor ibuprofen on organ blood flow during endotoxic shock were evaluated in a fluid-resuscitated porcine endotoxic shock model. Radiolabeled microspheres were used to measure regional blood flow. Escherichia coli endotoxin (0.1 mg/kg), infused intravenously over 40 min, reduced mean arterial blood pressure to 50 mmHg and systemic vascular resistance to 57% of control without affecting cardiac output. Endotoxin reduced blood flow to cerebrum (to 49% of control), kidney (to 25% of control), spleen, and skeletal muscle, while blood flow to left ventricle, stomach, and small and large intestines were unaffected. Sixty minutes after endotoxin administration, animals were randomized to one of three groups. Group I animals were controls and received no drug, group II animals received ibuprofen (12.5 mg/kg iv), and group III animals received naloxone (2 mg/kg iv) 60 min after endotoxin. Ibuprofen increased mean arterial blood pressure to 80 mmHg and increased blood flow to both cerebrum (to 92% of control) and kidney (to 47% of control). Plasma levels of thromboxane B2 and 6-ketoprostaglandin F1 alpha were increased 8- and 16-fold, respectively, after endotoxin, and both were decreased by ibuprofen. Naloxone increased mean arterial blood pressure to 62 mmHg but had no effect on regional blood flow or plasma cyclooxygenase metabolite levels. These data suggest that cyclooxygenase metabolites may contribute to decreased mean arterial blood pressure and reduced organ blood flow during endotoxic shock in the pig.

Failure of acute saralasin to reverse chronic hypertension in fetal lambs

1991 ◽  
Vol 260 (4) ◽  
pp. R811-R816
Author(s):  
D. F. Anderson ◽  
N. D. Binder
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Arterial Blood Pressure ◽  
Upper Body ◽  
Chronic Hypertension ◽  
Aortic Blood Flow ◽  
Flow Reduction ◽  
Arterial Blood ◽  
Aortic Blood ◽  
Blood Flow Reduction

Upper body arterial hypertension developed in 12 fetal lambs after chronic suprarenal aortic blood flow reduction. Sixty minutes after blood flow reduction, intravenous saralasin infusion was able to reduce upper body mean arterial blood pressure to control levels. Although saralasin infusion was able to decrease upper body arterial blood pressure after 1 day of hypertension, it was not able to return blood pressure to control levels. Three or more days later, saralasin was unable to cause a significant reduction in upper body arterial blood pressure. We conclude that, although the renin-angiotensin system has a role in maintaining the elevated blood pressure after greater than or equal to 1 day of suprarenal aortic blood flow reduction, some other mechanism also participates. We have ruled out a role for changing blood volume, and our results suggest that an elevation of plasma catecholamines is not responsible. Some other pathway for fluid regulation available to the fetus may be responsible.

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