Active clinical trials for "Wounds and Injuries"

Hepatorenal syndrome (HRS) is a common cause of acute kidney injury (AKI) in cirrhotic patients and has a one month survival rate of 50% and a 3 month survival rate of 20%. The leading theory behind HRS is selective vasoconstriction of renal vasculature in the setting of decreased systemic vascular resistance. Patients with liver cirrhosis suffer from a large degree of third spacing in the form of peripheral edema and ascites. In addition treatment with multiple drugs, including diuretics puts these patients at higher risks of prerenal AKI and ischemic acute tubular necrosis (ATN). AKI occurring due to HRS, prerenal AKI and ischemic or nephrotoxic ATN have different pathophysiologic mechanisms and are treated differently with significantly different outcomes. While renal perfusion is expected to be reduced in HRS and prerenal AKI, it is normal or increased in ATN. Prerenal AKI has the most favorable prognosis among these pathologies and treatment simply consists of volume expansion with blood, albumin, crystalloids or colloids. In clinical practice vasoactive agents such as midodrine and octreotide are used to increase the tone of splanchnic vessels and to improve renal perfusion. These interventions would not affect renal function in cases with ATN. Unfortunately, the diagnostic criteria proposed by the International Club for Ascites (ICA) for HRS are not specific and do not always exclude patients with other forms of acute kidney injury. Therefore, availability of a simple diagnostic tool for measurement of renal blood flow (RBF) at the bedside would be of great value in management of cases with cirrhosis of the liver presenting with acute reduction in kidney function. However, currently, there are no practical and simple tools available for this purpose. Contrast enhanced ultrasonography (CEU) involves the intravenous injection of gas-filled microbubbles to enhance the ultrasound image of the organs and mainly to assess tissue vascularity and blood flow. We and others have used CEU to assess changes in RBF in response to physiologic stimuli and therapeutic interventions. Here we propose a prospective, pilot diagnostic study to validate the use of CEU, in assessing RBF in cirrhotic patients with AKI, and to assess the utility of CEU to differentiate between causes of AKI in cirrhotic patients. Our hypothesis is that CEU will show arteriolar vasoconstriction and decreased blood flow in the renal cortex in patients with HRS which would not change in response to volume expansion. On the contrary, patients with prerenal AKI will have reduced RBF which will increase after volume expansion. Finally, those with ATN will not have a reduced RBF at baseline. We plan to enroll 25 patients with liver cirrhosis and acute kidney injury who are admitted to the University of Virginia hospital into the study. CEU will be performed on all subjects to measure baseline RBF. CEU will be repeated in all subjects within 24 hours after volume expansion with at least 1gm/kg of albumin (up to 100 gm/day) to assess a potential change. Hourly urine output and serum creatinine will be monitored for potential renal response to the volume expansion as part of clinical care. For the subgroup of subjects who receive treatment with combination therapy with albumin, midodrine, and octreotide (AMO) RBF assessment with CEU will be repeated after at least 48 hours of receiving this combination. Renal response will be assessed by monitoring urine output and serum creatinine monitored as part of clinical care. All subjects will have measurements of fractional excretion of sodium (FENa) and urea (FEUrea) and urine microscopy as a part of their routine clinical care (work up of AKI). The results of these tests and the response to volume expansion will be used to categorize subjects into three categories of AKI (HRS, prerenal AKI, ATN). Correlations between RBF and its changes between different therapeutic interventions and renal diagnosis will be tested in this study.

This is a study of factors, such as pain, family support, psychological history and alcohol/substance use, that may influence whether a person experiences depression after their spinal cord injury.

The purpose of the study is to gather information about patients with mild traumatic brain injury in order to develop guidelines for evaluation and treatment.

The study will provide evidence on the long term outcomes of mTBI in service members returning from Afghanistan and Iraq. In addition, the study will provide evidence on mTBI incidence, and symptom patterns. Self-reported assessments at baseline and follow-ups will be combined with data on health care utilization and military job performance. The work, symptoms, and family interaction outcomes of returning soldiers screening positive for mTBI, combined mTBI and PTSD, and soldier controls will be compared at 3 months, 6 months, and at one year. The assessments over time will permit descriptions of symptom changes for these populations. It is likely the study will find similar findings to those of previous civilian studies - that concussive symptoms often resolve within months of injury. However, some soldier subsets may have chronic problems. Determining the incidence and outcomes of individuals with mTBI will assist medical providers in determining the types of follow-ups needed by returning service members and suggest the development of additional treatment interventions. These results may also inform treatment of civilian populations with mTBI. The three primary hypotheses are: Concussive symptoms at the time of return from serving in Afghanistan and Iraq and symptoms persisting 3 months, 6 months, and 12 months after return will be associated with extent of exposure to combat, injury mechanism, associated injuries (co-occuring injuries), PTSD and other psychiatric co-morbidities, and number of deployment-related mTBIs. Returning troops reporting concussive symptoms at the time of return from deployment will have more work related problems at each follow-up (including lower rates of return to duty, return to work, and poor quality of work). The mTBI screening tool will be sensitive and specific to mTBI when compared to the criterion measure, which is a structured interview conducted by clinicians blinded to the screening results.

Acute kidney injury after cardiac surgery has been reported to increase morbidity and mortality. Several risk scoring models for prediction of aortic kidney injury after cardiac surgery have been developed. However, predictive accuracy of these models is stil unclear. The aim of this study is to evaluate the accuracy of four pre-existing prediction models using a gray zone approach in patients who underwent aortic surgery in our institution.

The purpose of this study is to evaluate whether standard volume computed tomography (CT) has impact on treatment in patients with suspicion of fractures of the wrist and carpus.

In the prehospital setting it would be helpful to assess primary changes in central blood volume or preload (venous return, stroke volume, diastolic ventricular volume) that occur during the stability phase following injury when regulatory mechanisms are still functioning. Obviously in this setting a non invasive bedside beat-to-beat index would be helpful. Pulse Transit Time (PTT) is the sum of Pre-Ejection Period (PEP), the time interval between the onset of ventricular depolarization and the ventricular ejection, and Vascular Transit Time (VTT), the time it takes for the pulse wave to travel from the aortic valve to the peripheral arteries (Obrist et al. 1979). PEP variations are known to correlate with reductions in central blood volume induced by head-up tilt (Chan et al., 2007b, 2008). The same authors also demonstrated that PTT variations follow closely PEP variations and therefore central blood volume variations (Chan et al., 2007b). Following central blood volume reductions induced by head-up tilting ventricular diastolic filling time increases involving an increase in PEP and PTT. Chan et al. (Chan et al., 2007b) concluded that PTT could have been used to assess early central hypovolemia and suggested that joint analysis of PTT and RR intervals could help in predicting the extent of blood volume loss. The investigators hypothesized that sympathetic drive associated with trauma would act on cardiac contractility through beta activity thus shortening PTT without reducing RR interval to the same extent in healthy hearts. We also hypothesized that progressive hypovolemia would lead to a rising of PTT (augmented diastolic filling time) and a RR interval shortening (relative tachycardia). In this study the investigators propose and index based on the beat-to-beat PTT/RR ratio to assess central hypovolemia in traumatic patients enrolled by our Helicopter Emergency Medical System (HEMS) in a prehospital setting.

The specific aims of this study are: 1) to assess the test-retest reliability of a modification of an existing wheelchair propulsion assessment and 2) validate the modification against traditional measures of physical strength, power, and endurance in a group of persons with spinal cord injury (SCI).

Objective: To investigate the movement strategy of breathing based on three-compartment model measured by optoelectronic plethysmography (OEP) and electromyography (EMG ) among individuals with and without spinal cord injury in supine posture during deep inspiration. Design: cross sectional repeated-measure with age matched control group. Setting: Motion Analysis Laboratory Participants: Seven tetraplegic and five paraplegic subjects and twelve age matched healthy controls were recruited. Intervention: Not applicable.

The purpose of this study is to determine whether the brains of persons with and without traumatic brain injury differ in a meaningful way when advanced technology images of the brain are taken using three newer technologies that visualize the brain using a combination of external/internal magnetic fields and radioactive tracers (molecules that emit detectable particles). The hope is that the results of this study will validate tools (help prove that diagnostic tools actually detect disease) for the diagnosis and treatment of traumatic brain injuries (TBI).