PURPOSE: To investigate the in vivo effects of cardiopulmonary bypass (CPB) and perioperative hemodilution on human skeletal muscle oxygen delivery and metabolism and to determine the dilution state at which these effects arise. METHODS: We conducted this observational study in adult patients undergoing CPB surgery. Microcirculatory data were obtained by ...

We reviewed 450 cases of caesarean delivery (January?December 2009) at the University of Ilorin Teaching Hospital in Nigeria. We analysed the association between caesarean delivery status (primary or previous) and the following outcomes: abnormal blood-loss, blood transfusion and perinatal mortality. Although significant differences were observed between primary and previous caesarean ...

BACKGROUND AND AIMS: Melatonin (MT) is rapidly transferred from the maternal to fetal circulation in humans. There is little knowledge about factors which influence the MT concentration (MTc) in the umbilical cord (UC) blood during delivery. The aim of our study was to evaluate the MT status in the UC ...

The purpose of this study was to examine VO(2) on-kinetics when the spontaneous blood flow (and therefore O(2) delivery) on-response was slowed by 25 and 50 s. The isolated gastrocnemius muscle complex (GS) in situ was studied in six anesthetized dogs during transitions from rest to a submaximal metabolic rate ...

In vivo video microscopy has been used to study blood flow regulation as a function of varying oxygen concentration in microcirculatory networks. However, previous studies have measured the collective response of stimulating large areas of the microvascular network at the tissue surface. Objective:  We aim to limit the area being ...

The use of epidural blood patches has become standard treatment for postdural puncture headache. Two cases suggest that there may occasionally be incomplete resorption of the blood patch, resulting in scarring in the epidural space that can be visualised using postpartum contrast injection and fluoroscopy. Both patients had a previous ...

Massive Transfusion is a part of Damage Control Resuscitation. The aim of transfusion therapy is to restore oxygen delivery to poorly perfused tissues and to treat the acute coagulopathy of trauma. The severity and complexity of modern injuries have led to the use of swift, protocol-driven care with the use ...

Microneedles have been an expanding medical technology in recent years due to their ability to penetrate tissue and deliver therapy with minimal invasiveness and patient discomfort. Variations in design have allowed for enhanced fluid delivery, biopsy collection, and the measurement of electric potentials. Our novel microneedle design attempts to combine ...

OBJECTIVE: The objective of the study was to assess risk factors for moderate and severe blood loss after cesarean delivery (CD). STUDY DESIGN: All planned (n = 32,716) and emergency (n = 47,942) cesareans, as reported over a 10-year period to the Medical Birth Registry of Norway, were analyzed separately ...

Objective: Oxygen therapy for infants and small children in developing countries is often not available. Entrainment devices may provide an accurate and precise concentration of oxygen when used at the flow rates appropriate for infants and small children. Methods: A continuously adjustable entrainment device was tested to determine the concentrations ...

Background: Perinatal inflammation is associated with adverse neurodevelopmental outcomes which maybe partly due to changes in the cerebral oxygen delivery/consumption relationship. We aimed to determine the critical oxygen delivery threshold of the brain of neonatal preterm ventilated lambs and to determine if the critical threshold is affected by exposure to ...

Systemic delivery of bioactive molecules in the CNS is hampered by the blood-brain barrier, which has bottlenecked noninvasive physiological study of the brain and the development of CNS drugs. Here we report that irradiation with an ultrashort pulsed laser to the blood vessel wall induces transient leakage of blood plasma ...

We determined the effect of cord blood collection before placental expulsion on postpartum maternal blood loss in a retrospective study between a group of cord blood donors and a group of non-donors. The study was conducted in a university hospital blood bank and obstetric services and included Spanish women entered ...

Cord blood banking has become more popular in recent years. Checking cord blood complete blood count (CBC) and white blood cell (WBC) differential counts (DCs) is essential before cryopreserving the cord blood units. Therefore, establishing the normal reference values of cord blood CBC and WBC DC is important in clinical ...

PURPOSE: The aim of this study was to investigate the effect of remifentanil continuous infusion on the blood flow in rabbit oral tissue during propofol and sevoflurane anesthesia, as well as its dose dependency. METHODS: Sixteen male tracheotomized Japan white rabbits were anesthetized with propofol or sevoflurane under mechanical ventilation. ...

The aim of this study was to investigate the effects of inhalational anaesthesia using low and high gas flow rates of nitrous oxide and desflurane on mucociliary clearance and pulmonary function. Fifty adult patients of the American Society of Anesthesiologists physical status I-II, aged between 18 and 70 years, were ...

Background  Ketamine hydrochloride is an anesthetic commonly utilized to obtain biological samples in various non-human primates. Its application alters individual hematologic and biochemical values. The aim of this study was to analyze its effect on blood parameters of Alouatta pigra. Method  We collected blood samples at 10 and 40 minutes after ...

In an era of medical cost containment, cost-effectiveness has become a major focus in healthcare. The effect of a new policy on the use of low fresh gas flow during maintenance of general anesthesia with volatile anesthetics was evaluated. The numbers and duration of general anesthesia cases using sevoflurane 5 ...

Early recognition of failure of oxygen delivery and knowledge of how medications can alter oxygen delivery allow clinicians to institute appropriate therapies in a timely manner and can result in improved patient outcomes. Oxygen delivery can be estimated and evaluated using a variety of methods, including arterial blood gas sampling, ...

Brachycephalic syndrome develops as a result of a specific build of splanchnocranium. In dogs of brachycephalic breeds, an impairment of correct gas exchange occurs. 5 French bulldogs at the age of 11-14 months, which suffered from continuous mixed-type dispnoea and lowered effort tolerance, were examined. Apart from the above-mentioned symptoms, ...

Acute renal failure (ARF) is the most important complication of rhabdomyolysis. Serial measurements of blood myoglobin might be useful for predicting rhabdomyolysis-induced ARF. Thirty patients with rhabdomyolysis were examined. The causes of rhabdomyolysis were trauma, burns, and ischemia, among others. Serial blood myoglobin levels were measured by immunochromatography, and the ...

The objective of this study was to quantify regional renal blood flow in humans. In nine young volunteers on a controlled diet, the lower abdomen was CT-scanned, and regional renal blood flow was determined by positron emission tomography (PET) scanning using H(2)(15)O as tracer. Measurements were performed at baseline, during ...

Abstract Introduction: Hemostasis remains a major challenge associated with laparoscopic renal surgery. We evaluated a cost-effective novel Doppler probe (DP) for assessment of vascular control during laparoscopic partial nephrectomy (LPN). Methods: We prospectively collected data during LPN procedures. We documented tumor location and size as well as subjective quality of ...

The purpose of this study was to compare the effects of norepinephrine (NE) and vasopressin on systemic hemodynamics, renal and mesenteric artery blood flow, inflammatory response and inducible nitric oxide synthase (iNOS) activity during endotoxin shock in streptozotocin-induced diabetic rats. The study was designed to include three sets of experiments: ...

Nonsteroidal anti-inflammatory drug usage has long revealed renoprotective prostaglandin actions on the renal microvasculature during increased pressor hormone influence, but whether increased cyclooxygenase (COX)-2 expression supports prostaglandin vasodilatory influence by interfering with the actions of ANG II remains unresolved. Therefore, we tested the hypothesis that COX-2 inhibition causes hemodynamic and ...

B-flow ultrasonography (BFU) is a new technology to detect blood circulation. It has been developed by using digitally encoded sonography, showing higher spatial and temporal resolution than Doppler imaging because of the clearer definition of the vessel lumen. Our study was performed on 55 patients, including 37 men (67.3%) and ...

This study evaluates reliability of current technology for measurement of renal arterial blood flow by breath-held velocity-encoded MRI. Overall accuracy was determined by comparing MRI measurements with known flow in controlled-flow-loop phantom studies. Measurements using prospective and retrospective gating methods were compared in phantom studies with pulsatile flow, not revealing ...

The endothelin type A (ETA) receptor was studied in six healthy subjects on two occasions with or without an ETA receptor (BQ-123) blockade. At 40 min of either BQ-123 or NaCl infusion, a concomitant infusion of the endothelin-1 (ET-1) precursor, big ET-1, was initiated to augment ET-1 formation. Blood samples ...

Pharmacologic or genetic deletion of components of the renin-angiotensin system leads to postnatal kidney injury, but the roles of these components in kidney development are unknown. To test the hypothesis that angiotensin II supports angiogenesis during postnatal kidney development, we quantified CD31(+) postglomerular microvessels, performed quantitative PCR analysis of vascular ...

We aimed to verify whether microcirculatory blood flow variability (MBFV) parameters calculated from beat-to-beat laser Doppler flowmetry (LDF) waveforms can be used instead of microcirculatory blood flow (MBF) as an index to discriminate different local microcirculatory regulation in terms of the opening condition of arteriolar openings (AO) at different sites. ...

PURPOSE OF REVIEW: Acute kidney injury (AKI) is a common complication of hospitalized patients and associated with significant morbidity and mortality. Numerous studies have documented that acute reductions in glomerular filtration rates are associated with significant in-hospital mortality. Moreover, patients progressing to dialysis-dependent AKI can have mortality rates that exceed ...

Endurance training has been associated with increased orthostatic intolerance. The purpose of the present study was to test the hypothesis that endurance training reduces renal vasoconstriction to orthostatic stress. Blood pressure, heart rate, and renal blood flow velocity were measured during a 25-min 60 degrees head-up tilt (HUT) test before ...

Renal blood flow (RBF) autoregulation is mediated by at least two mechanisms, the fast acting myogenic response (approximately 5 s) and slow acting tubuloglomerular feedback (TGF; approximately 25 s). Previous studies suggest epithelial Na(+) channel (ENaC) family proteins, beta-ENaC in particular, mediate myogenic constriction in isolated renal interlobar arteries. However, ...

Heme oxygenase (HO) is the enzyme responsible for the breakdown of heme-generating carbon monoxide (CO) and biliverdin in this process. HO-2 is the constitutively expressed isoform in most tissues, such as the kidney and vasculature. CO generated by HO is believed to be an important vasodilator in the renal circulation ...

BACKGROUND: Hypoxia-induced tubulointerstitial injury caused by loss of peritubular capillary (PTC) blood flow may be associated with progressive renal disease. Therefore, the maintenance of blood flow in PTCs may protect against loss of renal function. A long-acting calcium channel blocker, azelnidipine, has been shown to be useful in the treatment ...

Assessment of regional blood flow changes is difficult in the clinical setting. We tested whether conventional pulmonary artery catheters (PACs) can be used to measure regional venous blood flows by inverse thermodilution (ITD). Inverse thermodilution was tested in vitro and in vivo using perivascular ultrasound Doppler (USD) flow probes as ...

Current methods for measuring renal blood flow (RBF) are time consuming and not widely available. Contrast-enhanced ultrasound (CEU) is a safe and noninvasive imaging technique suitable for assessment of tissue blood flow, which has been used clinically to assess myocardial blood flow. We tested the utility of CEU in monitoring ...

OBJECTIVE: The purpose of this study was to evaluate the effect of 0.1 microg/kg/min of fenoldopam mesylate on renal flow and central hemodynamics measured by echocardiography in hemodynamically stable patients with preserved renal function undergoing cardiac surgery. DESIGN: Experimental observational study. SETTING: Single-institutional community hospital study. PARTICIPANTS: Thirty patients undergoing ...

Detection of the low-frequency (LF; approximately 0.01 Hz) component of renal blood flow, which is theorized to reflect the action of a third renal autoregulatory mechanism, has been difficult due to its slow dynamics. In this work, we used three different experimental approaches to detect the presence of the LF ...

BACKGROUND: There is no reliable method to monitor renal blood flow intraoperatively. In this study, we evaluated the feasibility and reproducibility of left renal blood flow measurements using transesophageal echocardiography during cardiac surgery. METHODS: In this prospective noninterventional study, left renal blood flow was measured with transesophageal echocardiography during three ...

Calcimimetics increase the sensitivity of the calcium sensing receptor (CaSR) to calcium ions (Ca(2+)) and allow for efficient control of uraemic hyperparathyroidism. Recent studies suggested an additional blood pressure-lowering action, the underlying mechanisms are as yet unknown. We infused R-568 and its enantiomer S-568, which has little activity at the ...

We analyzed the value of a new mathematical model for the quantification of renal cortical blood flow and fractional blood volume by contrast-enhanced ultrasound after the injection of sulfur hexafluoride-filled microbubbles. A vessel-mimicking phantom experiment was preliminarily performed which showed that the effect of microbubble diffusion is negligible compared with ...

OBJECTIVE: The objective of the study was to evaluate the fetal renal artery impedance in the context of inflammation-associated preterm birth. STUDY DESIGN: We conducted a prospective Doppler assessment of the fetal renal artery impedance in 70 singleton fetuses. The study group consisted of 56 premature fetuses (median, 28.1 [interquartile ...

Much of our understanding of the ionoregulatory and excretory physiology of blood-feeding insects can be traced to a series of papers by Simon Maddrell and colleagues in the 1970s and 1980s. These studies of the Malpighian (renal) tubules of Rhodnius prolixus revealed a number of physiological adaptations to the short-term ...

INTRODUCTION: Angiotensin II (Ang II) is a potential vasopressor treatment for hypotensive hyperdynamic sepsis. However, unlike other vasopressors, its systemic, regional blood flow and renal functional effects in hypotensive hyperdynamic sepsis have not been investigated. METHODS: We performed an experimental randomised placebo-controlled animal study. We induced hyperdynamic sepsis by the ...

Renal sympathetic nerve activity (RSNA) plays an important role in the control of renal hemodynamics and function. It achieves this control by changing the mean levels of activity and/or changing the power of the distinct frequencies that comprise this mean activity. My studies, presented in four parts, investigate how total ...

OBJECTIVE: To study the kinetics of lipid micro-emboli during cardiac surgery. DESIGN: Eleven pigs were studied. Seven of these were put on extracorporeal circulation. A shed blood phantom consisted of blood, saline and radioactive triolein was added to the circuit. Both venous and arterial blood samples were taken at short ...

BACKGROUND: Hemofiltration protocols using a citrate-buffered replacement solution offer the advantage of regional anticoagulation and a buffer effect. The role played by such fluids in clinical practice is not yet well established. The risk of electrolytic disorders, acid-base imbalance, or citrate accumulation should be clarified. We report on a renal ...

A high-resolution infrared (IR) camera was used to assess rhythmicity in localized renal blood flow, including the extent of regions containing nephrons with spontaneous oscillations in their individual blood flow. The IR imaging was able to follow changes in rat renal perfusion during baseline conditions, during occlusion of the main ...

Ibuprofen has been proposed as a preferential alternative to indomethacin in treating patent ductus arteriosus (PDA), because it is purported to have less renal, mesenteric, and cerebral vasoconstrictive effects. However, short and long-term safety concerns regarding ibuprofen remain. Continuous slow infusion of indomethacin also eliminates peripheral vasoconstriction and may thus ...