Treatment and Prevention of Diaphragm Fatigue Using Low-Dose Dopamine

2002 ◽  
Vol 3 (3) ◽  
pp. 140-149 ◽  
Author(s):  
Janet D. Pierce ◽  
Richard L. Clancy ◽  
Nan Smith-Blair ◽  
Robert Kraft
Keyword(s):  
Blood Flow ◽  
Intensive Care ◽  
Intensive Care Units ◽  
Low Dose ◽  
Aortic Blood Flow ◽  
Group Iii ◽  
Aortic Blood ◽  
Group I ◽  
Group Ii ◽  
Diaphragm Fatigue

There is increasing evidence that diaphragm fatigue is a major cause of failure in weaning patients frommechanical ventilation. Patients in intensive care units are often administered dopamine to improve renal blood flow without regard to its effect on diaphragmblood flow. The aimof this study was to investigate if intravenous low-dose dopamine, equivalent to the dose used in intensive care units, can treat and prevent diaphragmfatigue. Diaphragmfatigue was produced in anesthetized rats by inspiratory resistance loading (IRL). The effect on diaphragmshortening, diaphragmblood flow, and aortic blood flow was determined. When diaphragm fatigue was attained, group I was given saline for 30 min while maintaining IRL. At the time of diaphragm fatigue, group II was given low-dose dopamine (2 μg/kg/min) for 30 min while maintaining IRL. In group III, dopamine administration was started before and continued throughout the period of IRL. Administering dopamine after the development of diaphragm fatigue (group II) increased diaphragm performance as measured by increased diaphragmshortening and was accompanied by an increased diaphragmblood flow. Administering dopamine prior to and throughout IRL (group III) prevented diaphragmfatigue. Low-dose dopamine can prevent and/or reverse diaphragmfatigue in rats without a significant change in aortic blood flow. This effect of dopamine may be due to increased oxygen delivery associated with the increased diaphragm blood flow, resulting in less free radical formation and thus less muscle damage.

Microvascular pressures measured by micropipettes in isolated edematous rabbit lungs

1986 ◽  
Vol 60 (2) ◽  
pp. 539-545 ◽  
Author(s):  
J. U. Raj ◽  
R. D. Bland ◽  
S. J. Lai-Fook
Keyword(s):  
Blood Flow ◽  
Vascular Resistance ◽  
Weight Ratio ◽  
Dry Weight ◽  
Pressure Profile ◽  
Longitudinal Distribution ◽  
Lung Edema ◽  
Group Iii ◽  
Group I ◽  
Group Ii

To study the mechanical effects of lung edema on the pulmonary circulation, we determined the longitudinal distribution of vascular resistance in the arteries, veins, and microvessels, and the distribution of blood flow in isolated blood-perfused rabbit lungs with varying degrees of edema. Active vasomotor changes were eliminated by adding papaverine to the perfusate. In three groups of lungs with either minimal [group I, mean wet-to-dry weight ratio (W/D) = 5.3 +/- 0.6 (SD), n = 7], moderate (group II, W/D = 8.5 +/- 1.2, n = 10), or severe (group III, W/D = 9.9 +/- 1.6, n = 5) edema, we measured by direct micropuncture the pressure in subpleural arterioles and venules (20–60 micron diam) and in the interstitium surrounding these vessels. We also measured pulmonary arterial and left atrial pressures and lung blood flow, and in four additional experiments we used radio-labeled microspheres to determine the distribution of blood flow during mild and severe pulmonary edema. In lungs with little or no edema (group I) we found that 33% of total vascular pressure drop was in arteries, 60% was in microvessels, and 7% was in veins. Moderate edema (group II) had no effect on total vascular resistance or on the vascular pressure profile, but severe edema (group III) did increase vascular resistance without changing the longitudinal distribution of vascular resistance in the subpleural microcirculation. Perivascular interstitial pressure relative to pleural pressure increased from 1 cmH2O in group I to 2 in group II to 4 in group III lungs.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Different Bleeding Patterns with the Use of Levonorgestrel Intrauterine System: Are They Associated with Changes in Uterine Artery Blood Flow?

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Carlo Bastianelli ◽  
Manuela Farris ◽  
Stefania Rapiti ◽  
Roberta Bruno Vecchio ◽  
Giuseppe Benagiano
Keyword(s):  
Blood Flow ◽  
Uterine Artery ◽  
Endometrial Thickness ◽  
Power Doppler ◽  
Artery Blood Flow ◽  
Group Iii ◽  
Group I ◽  
Significant Difference ◽  
Before And After ◽  
Group Ii

Objective. Evaluate if different bleeding patterns associated with the use of the levonorgestrel intrauterine system (LNG-IUS) are associated with different uterine and endometrial vascularization patterns, as evidenced by ultrasound power Doppler analysis.Methodology. A longitudinal study, with each subject acting as its own control was conducted between January 2010 and December 2012. Healthy volunteers with a history of heavy but cyclic and regular menstrual cycles were enrolled in the study. Ultrasonographic examination was performed before and after six months of LNG-IUS placement: uterine volume, endometrial thickness, and subendometrial and myometrial Doppler blood flow patterns have been evaluated.Results. A total of 32 women were enrolled out of 186 initially screened. At six months of follow-up, all subjects showed a reduction in menstrual blood loss; for analysis, they were retrospectively divided into 3 groups: normal cycling women (Group I), amenorrheic women (Group II), and women with prolonged bleedings (Group III). Intergroup analysis documented a statistically significant difference in endometrial thickness among the three groups; in addition, mean pulsatility index (PI) and resistance index (RI) in the spiral arteries were significantly lower in Group I and Group III compared to Group II. This difference persisted also when comparing—within subjects of Group III—mean PI and RI mean values before and after insertion.Conclusions. The LNG-IUS not only altered endometrial thickness, but—in women with prolonged bleedings—also significantly changed uterine artery blood flow. Further studies are needed to confirm these results and enable gynecologists to properly counsel women, improving initial continuation rates.

scholarly journals Non-invasive evaluation of cerebral hemodynamic and intracranial pressure in pediatric neuroinfections

2018 ◽  
Vol 9 (4) ◽  
pp. 485-490
Author(s):  
М. А. Georgiynts ◽  
V. А. Коrsunov ◽  
О. М. Оlkhovska ◽  
К. E. Stoliarov
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cardiac Output ◽  
Intensive Care ◽  
Intracranial Pressure ◽  
Cerebral Perfusion ◽  
Flow Index ◽  
Non Invasive ◽  
Group I ◽  
Group Ii

The study of intracranial pressure (eICP), cerebral perfusion pressure (eCPP), cerebral blood flow index (CFI), zero flow pressure (ZFP) in 49 children hospitalized in the intensive care unit with severe course of neuroinfections was carried out. The level of consciousness was determined by the Glasgow pediatric scale. Monitoring of central and peripheral hemodynamics (ECG, heart rate, systolic, diastolic and mean blood pressure, and cardiac output), pulse oximetry, capnography, hemoglobin, hematocrit, total protein, urea, creatinine, lactate, glucose and serum electrolytes was done. An ultrasound scanner was used to perform ultrasound duplex scanning of blood flow in the left and middle cerebral artery (MCA), measuring maximum, minimum and average blood flow velocities, pulsation index (PI), and resistance index (RI). Based on the formulae of Edouard et al. indicators of eCPP, ZFP, CFI, eICP were calculated. The eSCP was also determined by the formulae of Kligenchöfer et al. and Bellner et al. All patients were divided into group I with RI > 1.3 and group II with RI < 1.3. It was found that eCPP in the group I was significantly less (29.5 ± 1.3 mm Hg) than in the II group (41.6 ± 1.7 mm Hg). Despite the lack of a reliable difference in blood pressure between groups I and II, the difference in eCPP was found due to a significant difference in eICP 34.6 ± 1.4 and 27.6 ± 0.89 mm Hg in I and II groups respectively. ZFP in group I was significantly higher than in group II. The indexes of the Glasgow coma scale was significantly lower in group I and 7.8 ± 0.6 points. There were observed direct moderate correlations between systolic blood pressure, cardiac output and eSRP and CFI, presumably associated with a loss of autoregulation. CFI in the group I was lower than in the group II. Thus, non-invasive examination of cerebral flow in MCA by duplex sonography revealed that PI > 1.3 is an informative marker of intracranial hypertension and reduction of cerebral perfusion, which is common in children with neuroinfections. To determine the eSRP and CFI it is advisable to use the formula of Edouard et al. and to determine the eICP the formula of Kligenchöfer et al. The obtained data can be useful for objectifying the severity of the condition, predicting the outcomes of neuroinfections, choosing the directions of intensive care and evaluating its effectiveness.

scholarly journals The effect of low dose midazolam in addition to ondansetron on post-operative nausea and vomiting in laparoscopic cholecystectomy – a comparative study

2014 ◽  
Vol 24 (1) ◽  
pp. 8-12
Author(s):  
MM Masum-Ul Haque ◽  
Montosh K Mondal ◽  
S Afroz ◽  
SS Akhter ◽  
Abdul Hye ◽  
...  
Keyword(s):  
Laparoscopic Cholecystectomy ◽  
Postoperative Nausea ◽  
Low Dose ◽  
Postoperative Nausea And Vomiting ◽  
Group Iv ◽  
Nausea And Vomiting ◽  
Group Iii ◽  
Group I ◽  
Group Ii ◽  
Post Operative Nausea

Background Nausea, retching and vomiting are among the most common postoperative complaints. Premedication with low dose midazolam in addition to ondansetron is more effective in controlling postoperative nausea and vomiting. Objectives This study was designed to observe the effect of low dose midazolam 7.5mg in addition to ondansetron 4mg on postoperative nausea and vomiting in laparoscopic cholecystectomy. Methods 100 patients of ASA grade I and II, age range 30-50 years and weight 50-70 kg were randomly selected by a blind envelop method. They were equally divided into four groups of 25 patients in group each. Group I received vitamin, Group II ondansetron 8mg, Group III ondansetron 8mg and midazolam 7.5mg and Group IV ondansetron 4mg and midazolam 7.5 mg orally one hour before operation. In the recovery room occurrence of nausea and vomiting was assessed for 24 hours. Results The incidence of nausea was in vitamin Group I 64%, in ond8 group II 32%, in ond8+mid7.5 group III 24% and in ond4+mid7.5 group IV 24%. The incidence among the groups was highly significant (p=0.008). The incidence of vomiting was in vitamin Group I 16%, in ond8 group II 16%, in ond8+mid7.5 group III 8% and in ond4+mid7.5 group IV 8%. The difference among the groups were not significant (p=0.808). Conclusion Low dose midazolam 7.5mg in addition to ondansetron 4mg is more effective in controlling postoperative nausea and vomiting in laparoscopic cholecystectomy. DOI: http://dx.doi.org/10.3329/jbsa.v24i1.19793 Journal of Bangladesh Society of Anaesthesiologists 2011; 24(1): 8-12

High-Dose Ascorbic Acid Decreases Cholesterolemic Factors of an Atherogenic Diet in Guinea Pigs

2007 ◽  
Vol 77 (2) ◽  
pp. 125-129
Author(s):  
Filis ◽  
Anastassopoulou ◽  
Sigala ◽  
Theodorou ◽  
Manouras ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Guinea Pigs ◽  
Low Dose ◽  
Plasma Concentrations ◽  
Atherogenic Diet ◽  
High Dose ◽  
Low Density ◽  
Group Iii ◽  
Group I ◽  
Group Ii

Background: The study evaluates the effect of a high supplemental dose of ascorbic acid (AA) on plasma concentrations of total cholesterol (TC), triglycerides (TG), total lipids (TL), and lipoprotein fractions high-density, very-low-density-, and low-density lipoprotein (HDL, VLDL, LDL) in guinea pigs fed with atherogenic diet. Methods: Group I consisted of 5 normally fed guinea pigs plus a low dose of AA (1 mg/100 g/day), group II consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a low dose of AA (1 mg/100 g/day), and group III consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a high dose of AA (30 mg/100 g/day). Cholesterolemic factors concentrations were determined after nine weeks. Results: Concentrations of TC, TG, TL, LDL, and VLDL were increased in group II compared to group I (p < 0.01 for all differences). Supplementation with a high dose of AA resulted in decreased concentrations of TC (p < 0.01), TG (p < 0.01), TL (p < 0.01), and LDL (p < 0.01) in group III compared to group II. Additionally, concentration of HDL was increased in group III compared to group II (p < 0.01). Conclusion: High-dose AA supplementation to an atherogenic diet decreases concentrations of TC, TG, TL, and LDL and increases concentration of HDL compared to low-dose AA.

Effect of norepinephrine on diaphragm contractility and blood flow

1990 ◽  
Vol 69 (6) ◽  
pp. 2019-2028 ◽  
Author(s):  
G. S. Supinski ◽  
A. F. DiMarco ◽  
J. Gonzalez ◽  
M. D. Altose
Keyword(s):  
Blood Flow ◽  
Group Iv ◽  
Arterial Flow ◽  
Force Frequency ◽  
Group Iii ◽  
Arterial Blood ◽  
Group I ◽  
Intramuscular Electrodes ◽  
Phrenic Artery ◽  
Group Ii

Recent studies have shown that diaphragm fatigue can be reversed by mechanical augmentation of phrenic arterial flow. The purpose of the present experiment was to determine whether it was possible to pharmacologically augment diaphragm blood flow and reverse fatigue by the administration of norepinephrine. Four groups of studies were performed, all employing our previously described in situ isometric canine diaphragm strip preparation (Supinski et al., J. Appl. Physiol. 60: 1789-1796, 1986). Group I studies examined the effects of norepinephrine on the contractility of the nonfatigued diaphragm in normotensive dogs, group II studies examined the effects of this drug on the contractility of the fatigued diaphragm in normotensive animals, and group III studies examined the effect of this drug on the contractility of the fatigued diaphragm in hypotensive animals. Group IV studies examined the effect of norepinephrine in normotensive animals in which the phrenic artery was cannulated and pump perfused at constant flow. Fatigue was induced in group II, III, and IV studies by rhythmically stimulating the diaphragm via intramuscular electrodes. Norepinephrine had no effect on the contractility of the nonfatigued diaphragm (group I). In normotensive (group II) and hypotensive animals (group III), norepinephrine elicited dramatic increases in arterial blood pressure and phrenic arterial flow and produced a significant upshift in the force-frequency curve of the fatigued diaphragm. However, when phrenic flow was held constant (group IV experiments), norepinephrine failed to augment the contractility of the fatigued diaphragm. These results indicate that 1) norepinephrine can increase phrenic blood flow and augment the contractility of the fatigued diaphragm in both normotensive and hypotensive conditions and 2) this effect of norepinephrine to partially reverse fatigue is secondary to its action to augment diaphragmatic blood flow.

Effects of nitroglycerin on forearm haemodynamics in patients with cirrhosis

1988 ◽  
Vol 74 (4) ◽  
pp. 433-436 ◽  
Author(s):  
M. Isabel Jiron ◽  
Samuel S. Lee ◽  
Raimondo Cerini ◽  
Domenico Pugliese ◽  
Antoine Hadengue ◽  
...  
Keyword(s):  
Blood Flow ◽  
Forearm Blood Flow ◽  
Inverse Correlation ◽  
Venous Occlusion ◽  
Group Iii ◽  
Dilatory Response ◽  
Age Related ◽  
Group I ◽  
Venous Distensibility ◽  
Group Ii

1. Basal forearm haemodynamics were studied by venous occlusion plethysmography in three groups of subjects: group I, healthy controls, group II, patients with cirrhosis age- and sex-matched with group I, and group III, an older group of patients with cirrhosis. Subsequently, responses to sublingual nitroglycerin were measured in group I and II subjects. 2. Controls responded to nitroglycerin with an increase in venous distensibility; group II patients had higher initial venous distensibility but did not respond to nitroglycerin. No other variables in either group were affected by nitroglycerin. 3. Group II and III patients differed in forearm blood flow and vascular resistance and venous distensibility. A significant inverse correlation was found between age and forearm blood flow (r = −0.57, P < 0.001) in all patients with cirrhosis. 4. We conclude that (a) venous tone is reduced in cirrhosis, possibly as a result of chronic venodilatation; (b) this venodilatation impedes further dilatory response to a small dose of nitroglycerin; (c) cirrhosis is also associated with age-related decreases in peripheral haemodynamics.

Towards an absolute measurement of the aortic blood flow in anaesthesia and intensive care

1998 ◽  
Vol 7 ◽  
pp. S16 ◽  
Author(s):  
R. Muchada ◽  
P. Tortoli ◽  
F. Guidi ◽  
B. Lavandier ◽  
D. Cathignol
Keyword(s):  
Blood Flow ◽  
Intensive Care ◽  
Absolute Measurement ◽  
Aortic Blood Flow ◽  
Aortic Blood

Enhanced Platelet Thromboxane Synthesis In Normotensive And Hypertensive Pregnancies With Insufficient Fetal Growth

1981 ◽  
Author(s):  
H C S Wallenburg ◽  
P Rotmans
Keyword(s):  
Blood Flow ◽  
Platelet Aggregation ◽  
Fetal Growth ◽  
Gestational Age ◽  
Control Group ◽  
Group Iii ◽  
Group I ◽  
Group Ii ◽  
Generating System ◽  
Platelet Thromboxane

In normal pregnancy platelet aggregation and blood flow in the uterine arteries could be modulated by the balance between the prostacyclin-generating system in the uterine arterial walls and the thromboxane-generating system in platelets. Since hypertensive pregnancies and pregnancies complicated by insufficient fetal growth are characterized by a diminished uteroplacental blood flow,the present study was performed to investigate platelet thromboxane synthesis in these conditions.Material and methods. The study was performed in a control group of 27 women with uncomplicated pregnancies and adequate-for-gestational age (AGA)infants(group I),23 women with uncomplicated pregnancies but small-for-gestational age(SGA) infants(group II); 18 women with pregnancy-induced hypertension (PIH) and AGA-infants(group III); 16 women with PIH and SGA infants(group V).All women were investigated in the last trimester of pregnancy. Venous blood was obtained in EDTA. Platelet aggregation was induced with thrombin( l I.U./ml final concentration)in platelet-rich plasma, and the amount of malondehyde(MDA)generated was measured spectrophotometrically after reaction with thiobarbituric acid. The amount of MDA is equivalent to that of HHT and a measure of the formation of thromboxane.Results. The amount of MDA (mmol/109 platelets ± S.D.)formed in group I was 5.35±0.8, in group II 6.32± 1.4,in group III 6.3 ± 1.5, and in group IV 6.4 ± 1.8. Groups II, III and IV were not different from each other, but were all significantly higher than group I(p < 0.01).Conclusion. The results indicate that pregnant women with a high incidence of a compromised uterine circulation-normotensive with SGA, hypertensive with AGA or SGA- as a group exhibit a more active platelet thromboxane-synthesis. This might be due to defective production of PGI2 by the uterine arterial wall.

scholarly journals The Impact of Blood Flow Rate and Duration of Dialysis Session on Nutritional Status in Hemodialysis Patients

2020 ◽  
Vol 12 (11) ◽  
pp. 106
Author(s):  
Nur Samsu ◽  
Fatmawati Fatmawati ◽  
Aurora Permatasari ◽  
Kartin Kartin ◽  
Wahyu Wulandari
Keyword(s):  
Blood Flow ◽  
Nutritional Status ◽  
Flow Rate ◽  
Blood Flow Rate ◽  
Group Iii ◽  
Class A ◽  
Group I ◽  
Group Ii ◽  
The Impact ◽  
Dialysis Time

BACKGROUND: Blood flow rate (BFR) and time of dialysis are important determinants of dialysis adequacy. This study aimed to determine the impact of higher BFR and longer dialysis time on nutritional status in chronic hemodialysis (HD) patients. METHODS: Real-world evidence (RWE) studies of 3 HD units in different hospitals that differ in BFR and/or dialysis time. Group I, HD 5 hr and BFR 200-250 mL/min; group II, HD 4 hr and BFR 270-320 mL/min, and group III, HD 4 hr and BFR 200-250 mL/min. All HD units use the same dialysate flow and dialysis frequency. Nutritional status was assessed using a 3-point scale Subjective Global Assessment. RESULTS: A total of 233 chronic HD patients were included, mean of age was 52 &plusmn; 12.9 years, 46.5% were male. There are 69.5% on SGA class A, 27.5% on SGA class B, and 3% on SGA class C. The proportion of SGA class A in group II was highest compared to group II and III (93.5% vs 79.0% vs 32.1% (p &lt;0.05). There was no SGA class C in group II, whereas 2.4% in group I and 7.4% in group III. In group II there was lower interdialytic weight gain (IDWG) and less use of anti-hypertensive drugs compared to group III (p &lt;0.05). CONCLUSION: Our study showed that higher BFR and longer dialysis time are associated with better nutritional status in chronic HD patients. A higher BFR seems to have a more substantial impact compared to a longer dialysis time. Keywords: blood flow rate, dialysis time, subjective global assessment, nutritional status

Sign in / Sign up

Export Citation Format

Share Document