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Biomedical subjects

R Kothari

Publications and source records attributed to R Kothari.

At least 37 records · Page 2Linked to original sources
PubMed1997

Early stroke recognition: developing an out-of-hospital NIH Stroke Scale.

OBJECTIVE: To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke. METHODS: A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using chi 2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke. RESULTS: Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%. CONCLUSION: Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed.

Adult↗
PubMed1997

Early hemorrhage growth in patients with intracerebral hemorrhage.

BACKGROUND AND PURPOSE: The goal of the present study was to prospectively determine how frequently early growth of intracerebral hemorrhage occurs and whether this early growth is related to early neurological deterioration. METHODS: We performed a prospective observational study of patients with intracerebral hemorrhage within 3 hours of onset. Patients had a neurological evaluation and CT scan performed at baseline, 1 hour after baseline, and 20 hours after baseline. RESULTS: Substantial growth in the volume of parenchymal hemorrhage occurred in 26% of the 103 study patients between the baseline and 1-hour CT scans. An additional 12% of patients had substantial growth between the 1- and 20-hour CT scans. Hemorrhage growth between the baseline and 1-hour CT scans was significantly associated with clinical deterioration, as measured by the change between the baseline and 1-hour Glasgow Coma Scale and National Institutes of Health Stroke Scale scores. No baseline clinical or CT prediction of hemorrhage growth was identified. CONCLUSIONS: Substantial early hemorrhage growth in patients with intracerebral hemorrhage is common and is associated with neurological deterioration. Randomized treatment trials are needed to determine whether this early natural history of ongoing bleeding and frequent neurological deterioration can be improved.

Adult↗
PubMed1997

Patients' awareness of stroke signs, symptoms, and risk factors.

BACKGROUND AND PURPOSE: We sought to determine knowledge at the time of symptom onset regarding the signs, symptoms, and risk factors of stroke in patients presenting to the emergency department with potential stroke. METHODS: Patients admitted from the emergency department with possible stroke were identified prospectively. A standardized, structured interview with open-ended questions was performed within 48 hours of symptom onset to assess patients' knowledge base concerning stroke signs, symptoms, and risk factors. RESULTS: Of the 174 eligible patients, 163 patients were able to respond to the interview questions. Of these 163 patients, 39% (63) did not know a single sign or symptom of stroke. Unilateral weakness (26%) and numbness (22%) were the most frequently noted symptoms. Patients aged > or = 65 years were less likely to know a sign or symptom of stroke than those aged < 65 years (percentage not knowing a single sign or symptom, 47% versus 28%, P = .016). Similarly, 43% of patients did not know a single risk factor for stroke. The elderly were less likely to know a risk factor than their younger counterparts. CONCLUSIONS: Almost 40% of patients admitted with a possible stroke did not know the signs, symptoms, or risk factor of a stroke. Further public education is needed to increase awareness of the warning signs and risk factors of stroke.

Aged↗
PubMed1997

Clinical application of the Ottawa ankle rules for the use of radiography in acute ankle injuries: an independent site assessment.

OBJECTIVE: Previous studies show that the clinical criteria known as the Ottawa ankle rules (OAR), used for determining the need for radiographs of the ankle when a fracture is suspected, have a sensitivity of 100%, a specificity of 50%, and an overall reduction in radiographs of the ankle of 28%. The purpose of this study was to further assess the clinical usefulness of the OAR when implemented in an emergency department of a level 1 trauma center. SUBJECTS AND METHODS: Over a 1-year period, all patients who were between 18 and 55 years old and who presented to the emergency department with blunt ankle trauma were examined by emergency department clinicians who used the OAR to determine the need for ordering ankle radiographs. RESULTS: Of 926 patients with blunt ankle trauma, 759 met OAR criteria for ordering radiographs of the ankle. Of these patients, 152 were found to have a fracture. Another 167 of the patients were determined not to need ankle radiographs. Through either telephone contact or medical records review. 152 (91%) of these 167 patients were successfully followed up for the purpose of detecting any missed fractures. Two missed fractures were discovered, but only one required plaster immobilization. Based on these numbers, overall sensitivity using the OAR was 99% (confidence interval, 95-100%), and specificity was 22%. We found an overall 16% reduction in the number of ankle films ordered. CONCLUSION: When implemented at a level 1 trauma center, the OAR can adequately screen for ankle fractures.

Acute Disease↗
PubMed1996

Neural network analysis of flow cytometry immunophenotype data.

Acute leukemia is one of the leading malignancies in the United States with a mortality rate strongly influenced by the phenotype. This phenotype is based on detection of cell associated antigens normally expressed during leucopoietic differentiation. In this regard, leukemia classified as lymphoid or myeloid by phenotype is also classified as a candidate for the corresponding chemotherapy protocol. Additionally, the subtype of leukemia based on the degree of differentiation and cell maturity influence prognosis, response to treatment, and median survival times. In this paper, we analyze immunophenotype flow cytometry data toward categorization of leukemia into subcategories based on lineage and differentiation antigen expression. Twenty-eight inputs (derived from the mean fluorescence intensity of up to 27 antibodies, and an additional binary input denoting the past diagnosis of leukemia) are used as input to a neural classifier to categorize a total of 170 cases into the lineage and differentiation categories of leukemia. The neural classifier consisted of a feed forward network trained using back propagation. A complexity regulation term (weight decay) was used to improve the generalization performance of the neural classifier. A training error of 0.0% and a generalization error of 10.3% was obtained for categorization based on lineage, while a training error of 0.0% and a generalization error of 10.0% was obtained for categorization based on differentiation. These results indicate that objective classification of multifaceted phenotypes in leukemia can be achieved for analyzing multiparameter data in flow cytometry and further categorization into the prognostic subtypes.

Adult↗
PubMed1996

Thrombolytic therapy for cerebral infarction.

Until recently, no clinically effective therapy for acute ischemic stroke has been available. Recent advances in the use of thrombolytic therapy for ischemic stroke appear promising in clinical care. As the use of thrombolytic therapy in acute stroke progress, emergency physicians (EPs) will become increasingly involved in its implementation. The EP must be cognizant of both prior and ongoing investigations in acute ischemic stroke therapy. To that end, this article reviews research in the field of thrombolytic therapy for acute ischemic stroke.

Acute Disease↗
PubMed1995

Frequency and accuracy of prehospital diagnosis of acute stroke.

BACKGROUND AND PURPOSE: This pilot study evaluated the frequency and accuracy of diagnosis of stroke made by prehospital care system dispatchers, emergency medical technicians (EMTs), and paramedics in one emergency medical services (EMS) system. In addition, the study determined patient prehospital triage and time intervals in the transport and examination of patients given a diagnosis of stroke by this EMS system. METHODS: We reviewed records of 4413 consecutive prehospital records of a two-tiered EMS system for patients with potential stroke. Hospital records were obtained for patients given a diagnosis of stroke or transient ischemic attack (TIA) by an EMS dispatcher, EMT, or paramedic. The EMS system studied serves a community of 13,000 within the greater Cincinnati area. RESULTS: Of 4413 EMS on-scene evaluations, the diagnosis of stroke or TIA was made by an EMT or paramedic for 96 patients (2%). Of the study population (n = 86), a final hospital discharge diagnosis of stroke or TIA was made for 62 patients (72%). EMS dispatchers correctly identified 52% and paramedics 72% of these 86 patients as having sustained a stroke or TIA. Twenty-two of the 86 patients required paramedic-level interventions, which included three intubations. Of the 24 patients whose symptoms were misdiagnosed as stroke or TIA by the paramedics, 16 (19%) had acute conditions for which effective therapies are available. Prehospital personnel arrived at the scene to examine potential stroke patients in a mean of 3 minutes after the emergency 911 call was received by the dispatcher. Patients transported by basic life support units (EMTs) arrived earlier at the hospital than did those transported by advanced life support units (paramedics) (40 +/- 1 versus 45 +/- 1 minutes, P = .004). However, patients transported by advanced life support units were seen by a physician sooner after arrival at the emergency department (10 +/- 2 versus 20 +/- 4 minutes, P = .02) and underwent computed tomography of the brain sooner (47 +/- 5 versus 69 +/- 10 minutes, P = .04). CONCLUSIONS: Prehospital evaluation of potential stroke patients can be accomplished promptly after the EMS system is activated. Urgent evaluation and transport of potential stroke patients is justified because paramedic-level interventions are frequently required and because almost 20% of patients with potential stroke have acute medical conditions for which effective specific therapies are available.

Aged↗
PubMed1994

Thrombolytic therapy for stroke.

The physiology of thrombi and the pharmacology of thrombolytic drugs are under active study and improved regimens for the dosing of thrombolytic agents have been developed. In the setting of myocardial infarction, recently reported differences among thrombolytic agents have been slight, including the frequency of thrombolysis-associated hemorrhagic stroke following tissue plasminogen activator or streptokinase. In the setting of ischemic stroke, recanalization rates following intravenous tissue plasminogen activator have been modest and at least partly dependent on clot size. Conclusions regarding clinical benefit will depend on the results of multicenter randomized trials that should available in 1995. Studies of locally administered intra-arterial thrombolytic therapy demonstrate high rates of clot lysis, but clinical benefits have yet to be established. The results of randomized trials will be important in clarifying any cause-effect relationships between thrombolytic therapy and symptomatic and asymptomatic intracranial hemorrhage. Thrombolytic therapy in the study of subarachnoid hemorrhage is under active investigation.

Animals↗
PubMed1993

Comparison of midazolam and diazepam for conscious sedation in the emergency department.

STUDY OBJECTIVE: To compare the efficacy of diazepam and midazolam when used for conscious sedation in emergency department patients. DESIGN: Prospective, randomized, double-blind, multicenter trial. SETTING: Three university EDs. TYPE OF PARTICIPANTS: Patients requiring one of the following procedures: abscess drainage, joint reduction, extensive suturing, chest tube insertion, or lumbar puncture. INTERVENTIONS: Diazepam (2.5 mg/mL) or midazolam (1 mg/mL) was administered until the desired level of sedation was achieved to a maximum of 5 mL. Fentanyl citrate was administered if needed for pain. MEASUREMENTS AND MAIN RESULTS: Thirty-three patients received diazepam and 36 received midazolam. Patients receiving midazolam had a greater degree of early sedation (P < .05), a higher 90-minute alertness scale score (P < .05), more patients ready for discharge at 90 minutes (P = .05), significantly less recall for the procedure (P < .02), and less pain on injection (P < .01) than patients who were given diazepam. CONCLUSIONS: Diazepam and midazolam are both effective for conscious sedation in ED patients. Midazolam causes less pain on injection, a significantly greater degree of early sedation, and a more rapid return to baseline function.

Adolescent↗
PubMed1981

Solid-state decomposition of alkoxyfuroic acids.

A series of alkoxyfuroic acids with alkyl lengths of n = 8-18 was synthesized, and the solid-state decomposition was studied. Bawn kinetics were adhered to, and the solid and liquid decomposition rate constants were established; they followed an Arrhenius relationship well, with energy of activations and preexponential factors being a function of the chain length. There was a break in this correlation between n = 14 and n = 16. The liquefaction points were of the expected correlation with inverse temperature. The isokinetic temperature (Ti) fell fairly well on the line demonstrated for other compound series.

Atmospheric Pressure↗
PubMed1980

Time and temperature dependence of disintegration and correlation between dissolution and disintegration rate constants.

Commercial prednisone tablets were subjected to dissolution tests by USP basket and paddle methods. It was found experimentally that disintegration adheres to an exponential decay law: ln(W/Wo) = -d(t-ti), where W is the nondisintegrated weight, d is a disintegration constant, t is time, and ti is a lag time. Dissolution has been reported to adhere to a similar law, where the dissolution constant K, follows a pseudo-Arrhenius relationship with changing temperature. Within a certain temperature range, this relationship also exists for the disintegration rate constant, d. A correlation exists in these tablets between K and d. The shaft length in the dissolution apparatus plays a part in the disintegration (and hence dissolution) rate and, therefore, is an important apparatus parameter affecting reproducibility.

Chemistry, Pharmaceutical↗
PubMed1976

Long-stay patients with long-stay drugs. A case review; a cause for concern.

The psychotropic medication of 200 long-stay psychiatric patients was reviewed by the consutant in charge of the ward, the ward doctor, and the ward sister. Those patients in whom medication was altered or stopped were reassessed by the same team after 6 months. About half the patients on medication had been receiving unnecessary or excessive medication.

Evaluation Studies as Topic↗
PubMed1975

Identification and definition of long-stay mental hospital population.

In a study to identify and define a central group of long-stay psychiatric patients who are resistant to discharge 422 were found who had been in hospital for eight to 23 years. These "problem" patients represented 40% of all long-stay patients. The total number of years that they had spent in hospital was nearly double that of the remaining patients. They were mostly unvisited, unoccupied, and single, and most were suffering from schizophrenia or organic psychosis. Half were in a good or reasonably good state of mental health, and three-quarters were in a good or reasonably good state of physical health. The findings have implications for the rehabilitation and treatment of these patients and also for the provision of community aftercare facilities.

Adult↗
PubMedDate not supplied

Public perception of stroke warning signs and knowledge of potential risk factors.

CONTEXT: Decreasing the time from stroke onset to hospital arrival and improving control of stroke risk factors depend on public knowledge of stroke warning signs and risk factors. OBJECTIVE: To assess current public knowledge of stroke warning signs and risk factors. DESIGN: A population-based telephone interview survey using random digit dialing conducted in 1995. SETTING: The Greater Cincinnati, Ohio, metropolitan area, the population of which is similar to that of the United States overall in age, sex, percentage of blacks, and economic status. PARTICIPANTS: Respondents with age, race, and sex that matched the population of patients with acute stroke. MAIN OUTCOME MEASURES: Knowledge of risk factors for stroke and warning signs of stroke as defined by the National Institute of Neurological Disorders and Stroke. RESULTS: Telephone calls were made to 17634 households, which yielded 2642 demographically eligible individuals. Interviews were completed by 1880 respondents (response rate, 71.2%). A total of 1066 respondents (57%) correctly listed at least 1 of the 5 established stroke warning signs, and of all respondents, 1274 (68%) correctly listed at least 1 of the established stroke risk factors. Of the respondents, 469 (57%) of 818 respondents with a history of hypertension listed hypertension, 142 (35%) of 402 respondents who were current smokers listed smoking, and 32 (13%) of 255 respondents with diabetes listed diabetes as a risk factor for stroke. Compared with those younger than 75 years, respondents 75 years or older were less likely to correctly list at least 1 stroke warning sign (60% vs 47%, respectively; P<.001) and were less likely to list at least 1 stroke risk factor (72% vs 56%, respectively; P<.001). CONCLUSION: Considerable education is needed to increase the public's awareness of the warning signs and risk factors for stroke. Respondents with self-reported risk factors for stroke are largely unaware of their increased risk. The population at greatest risk for stroke, the very elderly, are the least knowledgeable about stroke warning signs and risk factors.

Adult↗