scholarly journals Effect of L-arginine on renal blood flow in normal subjects and patients with hypoxic chronic obstructive pulmonary disease.

Thorax ◽  
1996 ◽  
Vol 51 (5) ◽  
pp. 516-519 ◽  
Author(s):  
T. Q. Howes ◽  
S. E. Keilty ◽  
V. L. Maskrey ◽  
C. R. Deane ◽  
S. V. Baudouin ◽  
...  
Author(s):  
Ираида Меньшикова ◽  
Iraida Men'shikova ◽  
Юлия Квасникова ◽  
Yuliya Kvasnikova ◽  
Елена Магаляс ◽  
...  

The aim is to study the interrelationships between the state of pulmonary, intracardiac hemodynamics and renal blood flow in patients with chronic obstructive pulmonary disease (COPD) complicated with the chronic cor pulmonale (CCP). 75 patients with COPD complicated with compensated CCP who had the study of pulmonary, intracardiac and renal hemodynamics with the method of ultrasound duplex scanning were examined. The patients were divided into 2 groups: the 1st group included 45 patients with COPD with pulmonary hypertension (PH) without clinical signs of right ventricle insufficiency; the 2nd group included 30 patients with COPD and PH complicated with right ventricle insufficiency. It was found out that the patients with COPD alongside with the progression of the disease and development of the heart insufficiency had an increase of renal vessel resistance (p<0.01) and a decrease of the velocity of renal blood flow (p<0.001). In the first group of patients there was found a consistent correlation between the increase of the vessel resistance in renal arteries and growth of general peripheral vessel resistance (p<0.001), of systolic pressure in the pulmonary artery (p<0.001) and diastolic dysfunction of the left ventricle (LV) (p<0.001), suggested the influence of these predictors on the velocity of the arterial blood flow in kidneys. In the 2nd group there was registered a strong correlation between the decrease of ejection fraction (EF) of LV and the increase of pulsation and resistive indices of arcuate arteries (r=0.69; p<0.01 and r=0.71; p<0.01, respectively), as well as the increase of end-diastolic volume, end-systolic volume of LV and speed parameters of the renal blood flow at all levels (r=0.67; p<0.01). The study of the relationship between the parameters of hemodynamics of the right ventricle (RV) and the state of the renal blood flow revealed a consistent correlation between the decrease of EF of RV and the decrease of diastolic rate at all levels of renal arteries (p<0.001), the increase of resistive (p<0.01) and pulsation indices (p<0.01) of the arterial system of kidneys. These correlations reflect a negative influence of both a left ventricle and right ventricle insufficiency on the state of the renal blood flow.


CHEST Journal ◽  
1987 ◽  
Vol 91 (6) ◽  
pp. 874-877 ◽  
Author(s):  
David L. Bowton ◽  
Peter T. Alford ◽  
Byron D. McLees ◽  
Donald S. Prough ◽  
David A. Stump

1964 ◽  
Vol 19 (2) ◽  
pp. 233-235 ◽  
Author(s):  
M. Henry Williams ◽  
Cecile Kane

When normal subjects listened to simulated breath sounds while breathing at their natural respiratory frequency there was a significant decrease of alveolar Pco2. The alveolar Pco2 did not fall further when these subjects listened to the simulator and breathed slowly, but when they breathed with the simulator at a very rapid frequency there was further fall of the PaCOCO2. When patients with chronic obstructive pulmonary disease listened to simulated breath sounds while breathing at their natural respiratory frequency there was a decrease of arterial Pco2 which fell further when the subjects breathed with the simulator at a slow respiratory rate. breathing, effect of auditory stimuli on; breathing rate and pulmonary function on chronic obstructive pulmonary disease; alveolar ventilation and auditory respiratory stimuli; respiratory frequency and ventilation Submitted on July 12, 1963


1983 ◽  
Vol 55 (1) ◽  
pp. 8-15 ◽  
Author(s):  
F. Bellemare ◽  
A. Grassino

The fatigue threshold of the human diaphragm in normal subjects corresponds to a transdiaphragmatic pressure (Pdi)-inspiratory time integral (TTdi) of about 15% of Pdimax. The TTdi of resting ventilation was measured in 20 patients with chronic obstructive pulmonary disease (COPD) and ranged between 1 and 12% of Pdimax (mean 5%). TTdi was significantly related to total airway resistance (Raw) (r = 0.57; P less than 0.05). Five of these patients were asked to voluntarily modify their TI/TT (ratio of inspiratory time to total cycle duration; from 0.33 to 0.49) so as to increase their TTdi from a control value of 8% to an imposed value of 17% of Pdimax. The imposed pattern induced a progressive decline in the high-frequency (150-350 Hz)/low-frequency (20-40 Hz) power ratio (H/L) of the diaphragm electromyogram (fatigue pattern), quantitatively similar to that seen in normal subjects breathing with similar TTdi levels. The decay in H/L was followed by a progressive fall in mean Pdi meanly due to decrease in gastric pressure swings. It is concluded that 1) the force reserve of the diaphragm in COPD patients is decreased because of a decrease in Pdimax; 2) the remaining force reserve of the diaphragm can be exhausted by even minor modifications in the breathing pattern; and 3) at a TI/TT of 0.40 our COPD patients can increase their mean Pdi 3-fold before reaching a fatiguing pattern of breathing compared with 8-fold in normal subjects.


2011 ◽  
Vol 36 (6) ◽  
pp. 821-830 ◽  
Author(s):  
Megan F.B. Sherman ◽  
Jeremy D. Road ◽  
Donald C. McKenzie ◽  
A. William Sheel

The objective of this study was to measure the magnitude of the muscle metaboreflex in people with chronic obstructive pulmonary disease (COPD) compared with healthy controls and to assess the relationships between disease severity, exercise capacity, and the magnitude of the muscle metaboreflex. Nine people with mild-to-severe COPD and 11 age- and gender-matched healthy controls performed isometric handgrip exercise (IHG), followed by postexercise circulatory occlusion (PECO) while hemodynamic changes were measured. Continuous measures of heart rate, arterial pressure, leg blood flow, leg vascular resistance, and total peripheral resistance were obtained. Participants then performed a cycle test to exhaustion. Heart rate, blood pressure, and blood flow responses during IHG and PECO were similar between the COPD group and healthy controls (p > 0.05). There was no association between disease severity or exercise capacity and the magnitude of the muscle metaboreflex. We observed a preserved muscle metaboreflex in mild-to-severe COPD, suggesting the metaboreflex is not a contributing factor to the development of exercise intolerance in this population.


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