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1.
Early MRI Blood Volume Changes in Constrictor Muscles Correlate With Postradiation Dysphagia.
Mierzwa, ML, Gharzai, LA, Li, P, Wilkie, JR, Hawkins, PG, Aryal, MP, Lee, C, Rosen, B, Lyden, T, Blakely, A, et al
International journal of radiation oncology, biology, physics. 2021;(2):566-573
Abstract
PURPOSE Predicting individual patient sensitivity to radiation therapy (RT) for tumor control or normal tissue toxicity is necessary to individualize treatment planning. In head and neck cancer, radiation doses are limited by many nearby critical structures, including structures involved in swallowing. Previous efforts showed that imaging parameters correlate with RT dose; here, we investigate the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) blood volume (BV) changes in predicting dysphagia. METHODS AND MATERIALS This study included 32 patients with locally advanced oropharyngeal squamous cell carcinoma treated with definitive chemoradiation on an institutional protocol incorporating baseline and early midtreatment DCE-MRI. BV maps of the pharyngeal constrictor muscles (PCM) were created, and BV increases midtreatment were correlated with the following parameters at 3 and 12 months post-RT: RT dose, Dynamic Imaging Grade of Swallowing Toxicity swallow score, aspiration frequency, European Organisation for Research and Treatment of Cancer HN35 patient-reported outcomes, physician-reported dysphagia, and feeding tube (FT) dependence. RESULTS The mean BV to the PCMs increased from baseline to fraction 10, which was significant for the superior PCM (P = .006) and middle PCM (P < .001), with a trend in the inferior PCM where lower mean doses were seen (P = .077). The factors associated with FT dependence at 3 months included BV increases in the total PCM (correlation, 0.48; P = .006) and middle PCM (correlation, 0.50; P = .004). A post-RT increase in aspiration was associated with a BV increase in the superior PCM (correlation, 0.44; P = .013),and the increase in the total PCMs was marginally significant (correlation, 0.34; P = .06). The best-performing models of FT dependence (area under the receiver operating curve [AUC] = 0.84) and aspiration increases (AUC = 0.78) included BV increases as well as a mean RT dose to middle PCM. CONCLUSIONS Our results suggest that midtreatment BV increases derived from DCE-MRI are an early predictor of dysphagia. Further investigation of these promising imaging markers to assess individual patient sensitivity to treatment and the patient's subsequent risk of toxicities is warranted to improve personalization of RT planning.
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2.
A randomized, controlled, double-blind crossover study on the effects of 1-L infusions of 6% hydroxyethyl starch suspended in 0.9% saline (voluven) and a balanced solution (Plasma Volume Redibag) on blood volume, renal blood flow velocity, and renal cortical tissue perfusion in healthy volunteers.
Chowdhury, AH, Cox, EF, Francis, ST, Lobo, DN
Annals of surgery. 2014;(5):881-7
Abstract
OBJECTIVE We compared the effects of intravenous administration of 6% hydroxyethyl starch (maize-derived) in 0.9% saline (Voluven; Fresenius Kabi, Runcorn, United Kingdom) and a "balanced" preparation of 6% hydroxyethyl starch (potato-derived) [Plasma Volume Redibag (PVR); Baxter Healthcare, Thetford, United Kingdom] on renal blood flow velocity and renal cortical tissue perfusion in humans using magnetic resonance imaging. BACKGROUND Hyperchloremia resulting from 0.9% saline infusion may adversely affect renal hemodynamics when compared with balanced crystalloids. This phenomenon has not been studied with colloids. METHODS Twelve healthy adult male subjects received 1-L intravenous infusions of Voluven or PVR over 30 minutes in a randomized, double-blind manner, with crossover studies 7 to 10 days later. Magnetic resonance imaging proceeded for 60 minutes after commencement of infusion to measure renal artery blood flow velocity and renal cortical perfusion. Blood was sampled, and weight was recorded at 0, 30, 60, 120, 180, and 240 minutes. RESULTS Mean peak serum chloride concentrations were 108 and 106 mmol/L, respectively, after Voluven and PVR infusion (P = 0.032). Changes in blood volume (P = 0.867), strong ion difference (P = 0.219), and mean renal artery flow velocity (P = 0.319) were similar. However, there was a significant increase in mean renal cortical tissue perfusion after PVR when compared with Voluven (P = 0.033). There was no difference in urinary neutrophil gelatinase-associated liopcalin to creatinine ratios after the infusion (P = 0.164). CONCLUSIONS There was no difference in the blood volume-expanding properties of the 2 preparations of 6% hydroxyethyl starch. The balanced starch produced an increase in renal cortical tissue perfusion, a phenomenon not seen with starch in 0.9% saline.
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3.
Use of online blood volume and blood temperature monitoring during haemodialysis in critically ill patients with acute kidney injury: a single-centre randomized controlled trial.
du Cheyron, D, Terzi, N, Seguin, A, Valette, X, Prevost, F, Ramakers, M, Daubin, C, Charbonneau, P, Parienti, JJ
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association. 2013;(2):430-7
Abstract
BACKGROUND Little is known about the clinical impact on cardiovascular stability during intermittent haemodialysis (IHD) for acute kidney injury (AKI) of online monitoring devices that control blood volume (BV) and blood temperature in the intensive care unit (ICU) setting. We compared different dialysis treatment modalities with or without these new systems among critically ill patients requiring IHD. METHODS In a prospective single-centre three-arm randomized controlled trial, 600 dialysis sessions in 74 consecutive AKI critically ill patients were involved to assess intradialytic hypotension. Standard dialysis therapy with constant ultrafiltration (UF) rate, cool dialysate and high sodium conductivity (Treatment A) was compared to regimens with adjunctive interventions including BV control (Treatment B) and the combination of BV and active blood temperature control (Treatment C). Each dialysis session was randomly assigned to one of the three treatment arms and served as statistical unit. RESULTS Five hundred and seventy-two dialysis sessions were analysed (188, 190 and 194 in Treatments A, B and C, respectively). Hypotension occurred in 16.6% treatments, with similar rates among the arms. Haemodynamic parameters and dialysis-related complications did not differ between therapies. Based on generalized estimating equation adjusted to dialysate sodium conductivity, higher Sequential Organ Failure Assessment the day of dialysis session, the need for vasopressors and lower systolic blood pressure at the onset of the session were identified as independent predictors of hypotensive episodes, whereas regimens containing the new online monitors were not. CONCLUSIONS These results suggest that both actively controlled body temperature and UF profiled by online monitoring systems have no significant impact on the incidence of intradialytic hypotension in the ICU setting. Further research is needed before the use of these new sophisticated automatic methods can be applied routinely to the ICU setting.
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4.
The effect of furosemide on intravascular volume status and electrolytes in patients receiving mannitol: an intraoperative safety analysis.
Bebawy, JF, Ramaiah, VK, Zeeni, C, Hemmer, LB, Koht, A, Gupta, DK
Journal of neurosurgical anesthesiology. 2013;(1):51-4
Abstract
BACKGROUND Mannitol is often used during intracranial surgery to improve surgical exposure. Furosemide is often added to mannitol to augment this effect. The concern exists, however, that the augmented diuresis caused by the addition of furosemide to mannitol may cause hypovolemia and hypoperfusion, hypokalemia, and hyponatremia. We examined the intraoperative safety of low-dose furosemide (0.3 mg/kg) combined with mannitol (1 g/kg). METHODS We observed 23 patients in a double-blind, block randomized, placebo-controlled study to examine the effects of furosemide (0.3 mg/kg) when combined with mannitol (1 g/kg) on surgical brain relaxation for tumor surgery. Mannitol and the study drug (furosemide or placebo) were administered, and arterial blood gases with electrolytes (sodium, potassium, and lactic acid) and urine output volume were recorded every 30 minutes for 3 hours. Plasma sodium, potassium, and lactic acid concentrations, and interval urine outputs, were compared across time and between furosemide-placebo assignment groupings, with a P<0.01 considered significant. RESULTS Although mannitol produced a large volume of diuresis (1533±335 mL), the addition of a low dose of furosemide substantially increased both the rate of production of urine for the first 90 minutes after administration and the total volume of urine produced (2561±611 mL, P<0.001, compared with placebo group). The addition of furosemide did not produce a serum potassium level below 3.8±0.7 mEq/L, a serum sodium level below 128.3±3.4 mEq/L, or a serum lactic acid level above 2.4±0.9 mmol/L. There were no differences in the plasma potassium concentration, sodium concentration, or lactic acid concentration between the drug groups at any time point. CONCLUSIONS Despite an increase in urine output by as much as 67%, adding low-dose furosemide to mannitol does not seem to produce significant electrolyte derangements or hypovolemia compared with the administration of mannitol alone.
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5.
Acute l-arginine supplementation increases muscle blood volume but not strength performance.
Alvares, TS, Conte, CA, Paschoalin, VM, Silva, JT, Meirelles, Cde M, Bhambhani, YN, Gomes, PS
Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme. 2012;(1):115-26
Abstract
l-Arginine (L-arg) is an amino acid precursor to nitric oxide (NO). Dietary supplements containing L-arg have been marketed with the purpose of increasing vasodilation, thereby elevating blood flow to the exercising muscle and enhancing the metabolic response to exercise. Our goal was to identify the acute effect of L-arg supplementation on biceps strength performance, indicators of NO production (nitrite and nitrate - NOx), and muscle blood volume (Mbv) and oxygenation (Mox) during recovery from 3 sets of resistance exercise. Fifteen males participated in a randomized, double-blind, placebo-controlled study. After withdrawing resting blood samples, the subjects were supplemented with 6 g of L-arg (ARG) or placebo (PLA). Monitoring of Mbv and Mox with near-infrared spectroscopy began 30 min after supplementation and lasted for 60 min. The exercise protocol (3 sets of 10 maximal voluntary contractions of isokinetic concentric elbow extension at 60°·s(-1), 2-min rest between sets) was initiated 80 min after supplementation. Blood samples were drawn at 30, 60, 90, and 120 min after supplementation. Repeated measures ANOVA showed that Mbv significantly (p ≤ 0.05) increased in ARG compared with the PLA during the recovery period of each set of resistance exercise. NOx, Mox, peak torque, total work, and set total work were not significantly different between groups. We found that acute L-arg supplementation increases Mbv during recovery from sets of resistance exercise with no increase in strength performance. It is still premature to recommend nutritional supplements containing L-arg as an ergogenic aid to increase muscle strength during resistance training in healthy subjects.
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6.
Water ingestion reduces skin blood flow through sympathetic vasoconstriction.
Lu, CC, Li, MH, Lin, TC, Chen, TL, Chen, RM, Tung, CS, Tseng, CJ, Ho, ST
Clinical autonomic research : official journal of the Clinical Autonomic Research Society. 2012;(2):63-9
Abstract
OBJECTIVE Water ingestion induces a pressor effect in patients with efferent baroreflex impairment and a mild pressor effect in elderly healthy subjects. However, water raised the total peripheral vascular resistance (TPR) without a prominent change in blood pressure in young healthy subjects. We try to investigate whether water elicits a cardiovascular response via regulating regional skin blood flow (SkBF) in young healthy subjects. METHODS In a randomized, controlled, crossover fashion, 15 healthy male subjects (19-27 years old) ingested either 500 (water session) or 50 ml of water (control). The heart rate, blood pressure, cardiac index, and TPR were measured using a Task Force Monitor. A laser Doppler velocimeter was used to determine the change in the SkBF at the left thenar eminence. Plasma catecholamines and their metabolites were also measured. RESULTS At 25 min after ingestion of 500 ml water, the cardiac index and SkBF significantly decreased compared to control. In contrast, the TPR significantly increased after ingestion of 500 ml water. Plasma dihydroxyphenylalanine significantly increased at 25 min after water. INTERPRETATION Water ingestion decreases the cardiac index to compensate for the increase in the TPR, leading to no net change in blood pressure in young healthy subjects. This study suggests that water decreases the SkBF, a mechanism that might account partly for the nature of osmopressor response to water in young healthy subjects.
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7.
Impaired natriuretic and renal endocrine response to acute volume expansion in pre-clinical systolic and diastolic dysfunction.
McKie, PM, Schirger, JA, Costello-Boerrigter, LC, Benike, SL, Harstad, LK, Bailey, KR, Hodge, DO, Redfield, MM, Simari, RD, Burnett, JC, et al
Journal of the American College of Cardiology. 2011;(20):2095-103
Abstract
OBJECTIVES We hypothesized an impaired renal endocrine and natriuretic response to volume expansion (VE) in humans with pre-clinical systolic dysfunction (PSD) and pre-clinical diastolic dysfunction (PDD). We further hypothesized that exogenous B-type natriuretic peptide (BNP) could rescue an impaired natriuretic response in PSD and PDD. BACKGROUND Recent reports suggest that in early systolic heart failure (HF), there is an impaired natriuretic response to acute VE. METHODS PSD was defined as left ventricular ejection fraction <40% without HF symptoms. PDD was defined as ejection fraction >50%, moderate to severe diastolic dysfunction by Doppler criteria, and no HF symptoms. A double-blinded, placebo-controlled, crossover study was employed to determine the renal response to VE (0.25 ml/kg/min of normal saline for 60 min) in the presence and absence of exogenous BNP. Twenty healthy control subjects, 20 PSD subjects, and 18 PDD subjects participated. RESULTS In healthy control subjects, urinary cyclic guanosine monophosphate (cGMP) and natriuresis increased after VE. In contrast, among PSD and PDD subjects, there was a paradoxical decrease in urinary cGMP and attenuated natriuresis. Pre-treatment with subcutaneous BNP resulted in similar increases in both urinary cGMP and natriuresis among healthy normal, PSD, and PDD subjects. CONCLUSIONS In PSD and PDD, there is impaired renal cGMP activation, which contributes to impaired natriuresis in response to VE. Impaired activation of urinary cGMP and reduced natriuresis may contribute to volume overload and the progression of HF among PSD and PDD subjects. Importantly, the impaired renal excretory response to VE is rescued by exogenous BNP in PSD and PDD.
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8.
Volume replacement with a balanced hydroxyethyl starch (HES) preparation in cardiac surgery patients.
Boldt, J, Mayer, J, Brosch, C, Lehmann, A, Mengistu, A
Journal of cardiothoracic and vascular anesthesia. 2010;(3):399-407
Abstract
OBJECTIVE Balanced fluids appear to be have advantages over unbalanced fluids for correcting hypovolemia. The effects of a new balanced hydroxyethyl starch (HES) were studied in cardiac surgery patients. DESIGN Prospective, randomized, unblinded study. SETTING Clinical study in a single cardiac surgery institution. PARTICIPANTS Sixty patients undergoing elective cardiac surgery with cardiopulmonary bypass. INTERVENTION Patients received either a balanced 6% HES 130/0.4 plus a balanced crystalloid (n = 30) or an unbalanced HES-in-saline plus saline (n = 30) to keep cardiac index >2.5 L/min/m(2). MEASUREMENTS AND MAIN RESULTS Base excess (BE), kidney function, inflammatory response (interleukins-6, -10), endothelial activation (intercellular adhesion molecule-1 [ICAM]), and coagulation (thromboelastometry, whole blood aggregation) were measured after induction of anesthesia, after surgery and 5 hours later, and at the 1st and 2nd postoperative days; 2,950 +/- 530 mL of balanced and 3,050 +/- 560 mL of unbalanced HES were given. BE was reduced significantly in the unbalanced group (from 1.11 +/- 0.71 mmol/L to -5.11 +/- 0.48 mmol/L after surgery) and remained unchanged in the balanced group. Balanced volume replacement resulted in significantly lower IL-6, IL-10, and ICAM plasma concentrations and lower urine concentrations of kidney-specific proteins than in the unbalanced group. After surgery, thromboelastometry data and platelet function were changed significantly in both groups; 5 hours thereafter they were significantly changed only in the unbalanced group. CONCLUSION A plasma-adapted HES preparation in addition to a balanced crystalloid resulted in significantly less decline in BE, less increase in concentrations of kidney-specific proteins, less inflammatory response and endothelial damage, and fewer changes in hemostasis compared with an unbalanced fluid strategy.
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9.
Effect of intermittent blood volume fluctuation of light resistance exercise after ingestion of the high-protein snacks on plasma branched-chain amino acid concentrations in young adults.
Kato, Y, Numao, S, Miyauchi, R, Suzuki, M
Journal of nutritional science and vitaminology. 2010;(4):255-9
Abstract
The study investigated exercise patterns resulting in the more efficient promotion of amino acid utilization. High-protein snacks (HPS; 15 g protein, 18 g sugar) were ingested by 8 young adult subjects 3 h after the basal meal ingestion. Sixty minutes after the HPS ingestion, the subjects performed arm flex/extend exercises for 15 min. The difference between 2 exercise patterns was compared. Pattern 1: High-number long-interval (HL) arm flex/extend (3+3 s) exercise; the HL group performed 9 sets of 15 exercises with a 10 s interval between sets. Pattern 2: Low-number short-interval (LS) arm flex/extend (3+3 s) exercise; the LS group performed 27 sets of 5 exercises with a 3-4 s interval between sets (135 exercises during 15 min, respectively). The plasma branched-chain amino acid (BCAA) concentrations were measured before the HPS ingestion, before the exercise, and 60 and 90 min after the HPS ingestion. The plasma BCAA concentrations increased significantly after the HPS ingestion. In the HL group, BCAA concentration increased consistently during the period and 60 to 90 min after the HPS ingestion. During the same period in the LS group the BCAA concentration stopped increasing. After HPS ingestion, a significantly greater suppressive effect on plasma BCAA concentration was seen in the LS group compared to the HL group. Results confirmed that the intermittent blood volume fluctuation in muscle tissue during the exercise pattern performed by the LS group had an effect on the utilization of nutritional components (BCAA, glucose) from the blood, and showed the possibility that the group where the blood volume in the muscle tissue increased/lowered with higher frequency was a more effective exercise pattern for nutrient utilization.
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10.
Effects of tilting and volume loading on plasma levels and urinary excretion of relaxin, NT-pro-ANP, and NT-pro-BNP in male volunteers.
Heringlake, M, Heide, C, Bahlmann, L, Eichler, W, Pagel, H, Schmucker, P, Wergeland, R, Armbruster, FP, Klaus, S
Journal of applied physiology (Bethesda, Md. : 1985). 2004;(1):173-9
Abstract
The polypeptide relaxin (RLX) has been suggested to play a role in cardiorenal integration and to be related to the natriuretic peptide system. We hence examined the effects of variations in thoracic blood volume and intravenous volume loading on plasma and urinary RLX levels and associated changes in natriuretic peptide levels in healthy men. Two groups of eight subjects were randomly tilted into a 15 degrees feet-down or a 15 degrees head-down position. Ten volunteers were crossover subjected to an infusion of 15 ml/kg of 0.9% NaCl (over 60 min) or control during an observation period of 10 h. Blood and urine were sampled at timed intervals. RLX, NH(2)-terminal prohormones of atrial natriuretic peptide (NT-pro-ANP), and NH(2)-terminal prohormones of brain natriuretic peptide (NT-pro-BNP) were determined by enzyme, radio-, and electrochemoluminescence immunoassays, respectively. NT-pro-ANP levels (in percentage of baseline levels) were higher (P < 0.05) during the head-down (124 +/- 13%) than during the feet-down position (82 +/- 6%). NT-pro-BNP and RLX were not affected by tilting. Volume loading induced a short-lasting increase in plasma NT-pro-ANP, a delayed increase in plasma NT-pro-BNP, had no effect on plasma RLX, and induced a parallel increase in urine flow, renal excretion of sodium, RLX, and NT-pro-BNP. It is concluded that variations in thoracic blood volume in healthy men are not associated with variations in plasma RLX. Increased urinary RLX and NT-pro-BNP excretion during volume loading suggest renal production and a possible role of kidney-derived RLX and brain natriuretic peptide in sodium homeostasis in men.