PubMed Health⌕ Search

Biomedical subjects

G L Kongable

Publications and source records attributed to G L Kongable.

16 recordsLinked to original sources
PubMed1998

Risk classification after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Prediction of patient outcome is an important aspect of the management and study of aneurysmal subarachnoid hemorrhage (SAH). In the present study, we evaluated the prognostic value of two multivariate approaches to risk classification, Classification and Regression Trees (CART) and multiple logistic regression, and compared them with the best single predictor of outcome, level of consciousness. METHODS: Data prospectively collected in the first Cooperative Aneurysm Study of intravenous nicardipine after aneurysmal SAH (NICSAH I, n = 885) were used to develop the prediction models. Low-, medium-, and high-risk groups for unfavorable outcome were devised using CART and a stepwise logistic regression analysis. Admission factors incorporated into both classification schemes were: level of consciousness, age, location of aneurysm (basilar versus other), and the Glasgow Coma Score. The CART prediction tree also branched on a dichotomy of admission glucose level. The two multivariate classifications were then compared with a prediction scheme based on the single best performing prognostic factor, level of consciousness in an independent series, NICSAH II (n = 353), and also in the original training dataset. RESULTS: A similar discrimination of risk was achieved by the three classification systems in the testing sample (NICSAH II). The 8%, 19%, and 52% rates of unfavorable outcome obtained from low-, medium-, and high-risk groups defined by LOC approximated those obtained using the more complex multivariate systems. CONCLUSION: Although multivariate classification systems are useful to characterize the relationship of multiple risk factors to outcome, the simple clinical measure LOC is favored as a concise and practical classification for predicting the probability of unfavorable outcome after aneurysmal SAH.

Calcium Channel Blockers↗
PubMed1998

Mild hypothermia: an alternative to deep hypothermia for achieving neuroprotection.

The role of excitotoxins in the ischemic cascade that results in ischemic neuronal death has been clearly defined and has brought about attempts to halt the progression of neurologic damage. Improved understanding of this process has allowed for the development of interventions to optimize neurologic outcome following periods of ischemia. Deep hypothermia (15-22 degrees C) has long been recognized as one method of achieving neuroprotection, but is not without serious implications and risks to the patient. Mild hypothermia (32-34 degrees C) is evolving as an alternative neuroprotective measure that has been shown to improve neurologic outcome in experimental models of ischemia and head injury, as well as in recent head injury clinical trials. It has been safely used intraoperatively in a large series of patients undergoing craniotomy. Mild hypothermia is a technique that may soon be commonly employed alone or in conjunction with other methods of neuroprotection. Nurses caring for patients undergoing this technique must be aware of the practice implications associated with this procedure and adapt their care accordingly.

Brain Ischemia↗
PubMed1998

Cigarette smoking as a cause of aneurysmal subarachnoid hemorrhage and risk for vasospasm: a report of the Cooperative Aneurysm Study.

OBJECT: Cigarette smoking is associated with aneurysmal subarachnoid hemorrhage (SAH) and subsequent vasospasm. The purpose of this study was to quantify this association. METHODS: Nearly 3500 patients with SAH from North America and Europe have been enrolled in five different multicenter, controlled studies coordinated at the Neuroclinical Trials Center of the Virginia Neurological Institute at the University of Virginia. Among the prospective data gathered were whether the patient smoked at the time of their most recent SAH and the evolution of angiographic vasospasm. The rate of smoking in the patients enrolled in the studies was compared with the expected rate by using a chi-square statistic adjusted for age and gender, in the general population in the United States (U.S.) and Europe. In virtually all age and gender subgroups, and for the combined populations in the five clinical trials, patients with SAH reported current smoking rates 2.5 times higher than expected based on U.S. and European national surveys (p < 0.0001). Cigarette smoking was also associated with younger age at onset of SAH (5-10 years, p < 0.0001) and increased incidence of clinically confirmed vasospasm (p < 0.005). CONCLUSIONS: The findings of a significantly increased representation of current cigarette smokers in the study populations and significant association with younger age at the time of SAH and increased incidence of vasospasm concur with recent reports of smoking as a significant risk factor for ruptured aneurysms and subsequent vasospasm.

Adolescent↗
PubMed1997

Long-term outcome after surgical excision of parenchymal arteriovenous malformations in patients over 60 years of age.

BACKGROUND: Age is considered an important limiting factor for surgical excision of parenchymal arteriovenous malformations (AVMs) and a more conservative therapeutic approach has been advocated in the elderly. There are no studies available investigating the long-term outcome after surgical excision of parenchymal AVMs in patients over 60 years of age. METHODS: We report the surgical outcome after excision of an AVM in a series of 13 consecutive patients older than 60 years. Medical records were analyzed retrospectively. RESULTS: Hemorrhage was the mode of presentation in all patients. Three patients were admitted in a comatose state. Surgery was performed within 1 week from the initial bleeding in seven cases and within 2 weeks in five cases. There were no deaths directly related to surgery in this series. However, one patient died as a result of an intracranial hemorrhage complicating preoperative embolization and another patient died 3 months after surgery from intervening medical complications. During the follow-up period (mean 46 months), three more patients had died 8, 19, and 48 months after surgery, respectively. Of the remaining eight patients, six are doing well and are independent in the activities of daily living. One patient is independent but requires supervision, and the remaining one was lost to follow-up. CONCLUSIONS: Age alone should no longer be considered a contraindication to treatment. In selected cases, surgery can be performed safely even in the elderly patient with an AVM. After surgical excision, elderly patients have the potential for several years of active life.

Aged↗
PubMed1997

Education to improve stroke awareness and emergent response. The NINDS rt-PA Stroke Study Group.

Patients delay in responding to stroke as an emergency in part because they have deficient information about the disease and treatment. Healthcare providers may also have a lack of information about stroke assessment and management, which could attribute to delays in patient care. In order to provide early, rapid stroke treatment in eligible persons, the public and the healthcare community must be informed. Information on stroke risk, symptoms and treatment should be provided to those likely to experience stroke, the general public and the emergency and medical communities who may witness and intervene when stroke occurs. Programs developed at the eight centers of the National Institute of Neurological Disorders and Stroke (NINDS) rt-PA stroke trial provide a sampling of approaches that increase awareness in these groups. Lessons learned include: 1. Program planning should start with a community needs assessment. 2. A variety of strategies can be applied to meet the community needs and resources. 3. Educational principles and models should be utilized in planning effective programs. 4. The message must be simple: "Stroke is an emergency. Time is brain".

Cerebrovascular Disorders↗
PubMed1996

Innovations in aneurysmal subarachnoid hemorrhage: intracisternal t-PA for the prevention of vasospasm.

Aneurysmal subarachnoid hemorrhage (SAH) affects approximately 30,000 people each year in North America. At least 30% of these patients will develop vasospasm as a result of the initial hemorrhage, and two thirds of these develop permanent disabilities or die. Blood deposited into the basal cisterns from the ruptured aneurysm can form thick clots around the major cerebral vessels. The by-products of the hemolyzed clots are believed to be responsible for the subsequent development of vasospasm. Hypervolemic, hypertensive, hemodilution therapy (HHHT) and nimodipine may improve outcome in some cases but there is no therapy known to prevent vasospasm in all patients. One potential therapeutic agent under investigation is tissue plasminogen activator (t-PA), a fibrinolytic enzyme. Instilled into the basal cisterns at time of aneurysm clipping, t-PA dissolves the clot so spasmogenic substances may be removed, thus preventing or reducing the severity of vasospasm.

Aged↗
PubMed1996

Gender-related differences in aneurysmal subarachnoid hemorrhage.

Female gender is a recognized risk factor for the occurrence of aneurysmal subarachnoid hemorrhage. In the present study the authors analyzed differences in admission characteristics and outcome between 578 women (64%) and 328 men (36%) who were enrolled in a recently completed clinical trial. The female-to-male ratio was nearly 2:1. The women in the study were older than the men (mean age 51.4 years vs 47.3 years, respectively, p<0.001). Female patients harbored aneurysms of the internal carotid artery more frequently than male patients (36.8% vs. 18.0%, p<0.001) and more often had multiple aneurysms (32.4% vs. 17.6%, p<0.001). On the other hand, anterior cerebral artery aneurysms were more commonly encountered in men (46.1% in men vs. 26.6% in women, p<0.001). Other baseline prognostic factors were balanced between the gender groups. Surgery was performed equally in both sexes (98%), although the time to operation was shorter for women (mean 3.6 days for women vs. 5.3 days for men, p = 0.0002). In the placebo group, the occurrence of vasospasm was not statistically different between the two groups. Primary causes of death and disability were the same, and favorable outcome rates at 3 months were not statistically different between the genders (69.7% for women vs. 73.4% for men, p = 0.243). The odds of a favorable outcome in women versus one in men were not statistically significant either before of after adjustment for age. These observations lead the authors to suggest that although women are older and harbor more aneurysms, the 3-month outcome for women and men who experience aneurysmal subarachnoid hemorrhage is the same.

Adult↗
PubMed1996

Age and outcome after aneurysmal subarachnoid hemorrhage: why do older patients fare worse?

Advanced age is a recognized prognostic indicator of poor outcome after subarachnoid hemorrhage (SAH). The relationship of age to other prognostic factors and outcome was evaluated using data from the multicenter randomized trial of nicardipine in SAH conducted in 21 neurosurgical centers in North America. Among the 906 patients who were studied, five different age groups were considered: 40 years or less, 41 to 50, 51 to 60, 61 to 70, and more than 71 years. Twenty-three percent of the individuals enrolled were older than 60 years of age. Women outnumbered men in all age groups. Level of consciousness (p = 0.0002) and World Federation of Neurological Surgeons grade (p = 0.0001) at admission worsened with advancing age. Age was also related to the presence of a thick subarachnoid clot (p = 0.0001), intraventricular hemorrhage (p = 0.0003), and hydrocephalus (p = 0.0001) on an admission computerized tomography scan. The rebleeding rate increased from 4.5% in the youngest age group to 16.4% in patients more than 70 years of age (p = 0.002). As expected, preexisting medical conditions, such as diabetes (p = 0.028), hypertension (p = 0.0001), and pulmonary (p = 0.0084), myocardial (p = 0.0001), and cerebrovascular diseases (p = 0.0001), were positively associated with age. There were no age-related differences in the day of admission following SAH, timing of the surgery and/or location, and size (small vs. large) of the ruptured aneurysm. During the treatment period, the incidence of severe complications (that is, those complications considered life threatening by the reporting investigator) increased with advancing age, occurring in 28%, 33%, 36%, 40%, and 46% of the patients in each advancing age group, respectively (p = 0.0002). No differences were observed in the reported frequency of surgical complications. No age-related differences were found in the overall incidence of angiographic vasospasm; however, symptomatic vasospasm was more frequently reported in the older age groups (p = 0.01). Overall outcome, assessed using the Glasgow Outcome Scale at 3 months post-SAH, was poorer with advancing age (p < 0.001). Multivariate analysis of overall outcome, adjusting for the different prognostic factors, did not remove the age effect, which suggests that the aging brain has a less optimal response to the initial bleeding. Age as a risk factor is a continuum; however, there seems to be a significant increased risk of poor outcome after the age of 60 years.

Adult↗
PubMed1994

Angiographic characteristics of dural arteriovenous malformations that present with intracranial hemorrhage.

Dural arteriovenous malformations (dAVMs) are uncommon lesions that constitute about 12% of all the arteriovenous malformations. Depending on the location and the hemodynamics of the lesion, bruit, focal neurological deficit, and visual symptoms represent the more common presentation modalities. Although uncommon, intracranial hemorrhage can occur. In the present study, we report six patients with dural arteriovenous malformation that presented with intracranial hemorrhage. In five cases the hemorrhage was intraparenchymal (localized to the parietooccipital area in three), while it was confined to the subarachnoid space in the remaining one. The dAVM involved the transverse sinus in three cases, was based along the tentorial incisura in two, and was at the level of the torcular Herophili in one. Leptomeningeal drainage was present in all the cases. Aneurysmal dilatation of the draining vein(s) was identified in three. Sinus stenosis/occlusion was identified in two of the four patients with a dAVM draining into a major dural sinus. Four patients underwent pre-operative embolization, and all patients had surgical resection of their lesions. Anatomical cure, as defined by absence of any residual dAVM on postoperative angiogram, was achieved in all six patients. We conclude that several findings such as leptomeningeal drainage, location outside a major venous sinus, variceal dilatation, sinus stenosis/occlusion increase the risk of bleeding and are frequently observed in those dAVMs that present with intracranial hemorrhage. Recognition of these angiographic features is critical in planning a therapeutic approach tailored to the characteristics of the individual case. When these angiographic findings are present, prompt and definitive treatment is mandatory.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Electrocardiographic abnormalities after nontraumatic subarachnoid hemorrhage.

Electrocardiographic (ECG) abnormalities and rhythm disorders are frequently observed in the acute phase after spontaneous subarachnoid hemorrhage (SAH). These abnormalities are benign and transient in most cases; however, in some patients they can take the form of life-threatening arrhythmias such as ventricular flutter/fibrillation and torsade de pointe. Among the ECG abnormalities observed, prolongation of the Q-T interval, especially if associated with hypokalemia, deserves particular attention because it is frequently present in those patients who will develop life-threatening ventricular arrhythmias. In some cases, the ECG abnormalities mimic those observed in the setting of acute myocardial infarction. Elevated creatine phosphokinase-myocardial fraction isoenzyme, suggesting underlying cardiac damage, has also been reported. The pathophysiology of these abnormalities is related to an imbalance of autonomic cardiovascular control. Because some electrical and morphological heart abnormalities are experimentally induced by catecholamine injection, the role of circulating catecholamines has been investigated in depth. Pathologically, the hearts of patients who die after SAH can show a peculiar morphological lesion defined as "myocytolysis." Intramyocardial hemorrhages have also been described. These observations confirm the utility of continuous cardiac monitoring in patients with SAH.

Acute Disease↗
PubMed1993

Pilot randomized trial of tissue plasminogen activator in acute ischemic stroke. The TPA Bridging Study Group.

BACKGROUND AND PURPOSE: Early thrombolytic therapy with recombinant tissue-type plasminogen activator is a theoretically attractive approach to the treatment of acute focal cerebral ischemia. In preparation for a larger multicenter trial, three centers piloted a protocol for a randomized, double-blind, placebo-controlled trial of intravenous recombinant tissue-type plasminogen activator begun within 3 hours of the onset of symptoms of acute stroke to test its feasibility and to explore trends. METHODS: Eligible patients had pretreatment computed tomographic scanning, gave informed consent, and began treatment with either 0.85 mg/kg recombinant tissue-type plasminogen activator or placebo as soon as possible, but no later than 180 minutes after stroke onset. Patients were stratified by whether treatment was begun within 90 minutes or 91 to 180 minutes from onset. The primary end point was the proportion of patients in each group who improved by 4 or more points on the National Institutes of Health Stroke Scale at 24 hours, as determined by a separate blinded evaluator. RESULTS: Twenty-seven patients were randomized: 20 (10 recombinant tissue-type plasminogen activator, 10 placebo) within 90 minutes, and 7 (4 recombinant tissue-type plasminogen activator, 3 placebo) from 91 to 180 minutes. Median baseline Stroke Scale scores were 16 (minimum = 5, maximum = 26) for the recombinant tissue-type plasminogen activator-treated group and 11 (minimum = 3, maximum = 21) for the control subjects in the group treated within 90 minutes. Six patients treated with recombinant tissue-type plasminogen activator within 90 minutes improved by 4 or more points at 24 hours compared with 1 patient in the placebo group (P < .05, Fisher's Exact Test). Two patients in each group in the 91- to 180-minute arm improved. One fatal intracerebral hemorrhage occurred in the placebo group. CONCLUSIONS: A randomized, double-blind, placebo-controlled trial of recombinant tissue-type plasminogen activator very early in acute stroke is feasible. Preliminary observations suggest that recombinant tissue-type plasminogen activator treatment within 90 minutes may be associated with early neurological improvement. Larger studies are needed so that the potentially serious short-term risks of this treatment can be assessed in relation to meaningful long-term benefit.

Aged↗
PubMed1992

Urgent therapy for stroke. Part I. Pilot study of tissue plasminogen activator administered within 90 minutes.

BACKGROUND AND PURPOSE: Thrombolytic agents hold theoretical promise as therapy for cerebral infarction. This study was designed to evaluate the safety of tissue plasminogen activator, to accomplish urgent patient treatment, and to estimate potential efficacy of tissue plasminogen activator. METHODS: Following neurological evaluation and computed tomography of the brain, patients with acute ischemic stroke were evaluated and treated with intravenous tissue plasminogen activator under an open-label, dose-escalation design within 90 minutes from symptom onset. End points examined included symptomatic and asymptomatic intracranial hematoma, systemic hemorrhage, and neurological outcome at 2 hours, 24 hours, and 3 months. RESULTS: Seventy-four patients were treated within 90 minutes of symptom onset over seven dose tiers of tissue plasminogen activator, ranging from 0.35 mg/kg to 1.08 mg/kg. Intracranial hematoma with associated neurological deterioration occurred in three patients and was related to increasing doses of tissue plasminogen activator (p = 0.045). Intracranial hematoma did not occur in any of the 58 patients treated with less than or equal to 0.85 mg/kg. Major neurological improvement occurred in 22 patients (30%) at 2 hours from the initiation of tissue plasminogen activator and in a total of 34 patients (46%) at 24 hours, but major neurological improvement was not related to increasing doses of tissue plasminogen activator or to stroke type. CONCLUSIONS: Patients with acute stroke can be evaluated and treated within 90 minutes. Tissue plasminogen activator for acute ischemic infarction is not without risk, but the potential for clinical benefit justifies a randomized clinical trial. To date, differences in hemorrhagic risk or neurological benefit of tissue plasminogen activator for particular ischemic stroke types are not apparent.

Aged↗
PubMed1992

Urgent therapy for stroke. Part II. Pilot study of tissue plasminogen activator administered 91-180 minutes from onset.

BACKGROUND AND PURPOSE: Renewed interest in thrombolytic therapy as potential treatment for patients with acute ischemic stroke prompted a dose-escalation safety study of tissue plasminogen activator in patients with very early (less than or equal to 90 minutes; see Part I) neurological symptoms. To test whether this stringent entry window might be safely lengthened, a second study was organized to test tissue plasminogen activator in patients with symptoms of 91-180 minutes' duration before treatment. METHODS: An open-label, dose-escalation design was chosen. Eligible patients had pretreatment head computerized tomographic scanning and treatment begun 91-180 minutes from stroke onset. End points examined included the incidence of symptomatic and asymptomatic intracranial hemorrhage, other bleeding, and clinical outcome at 2 hours, 24 hours, and 3 months after treatment. RESULTS: Twenty patients were treated at three hospitals in 13 months. Three doses were tested: 0.6 mg/kg (n = 8), 0.85 mg/kg (n = 6), and 0.95 mg/kg (n = 6). Two patients, one each at the two highest doses, sustained fatal intracerebral hemorrhages. Three patients (15%) improved by greater than or equal to 4 points on the National Institutes of Health Stroke Scale by 24 hours. CONCLUSIONS: These observations suggest that tissue plasminogen activator treatment of acute ischemic stroke 91-180 minutes from onset in doses of greater than or equal to 0.85 mg/kg is attended by a risk of intracerebral hemorrhage approximating 17% (range 3-44%, 95% confidence interval). The rate of early neurological improvement observed in this study was small but does not exclude an improvement over the natural history. Future study with placebo control subjects and stratification by time to treatment is indicated.

Aged↗
PubMed1990

The International Cooperative Study on the Timing of Aneurysm Surgery. Part 1: Overall management results.

The International Cooperative Study on the Timing of Aneurysm Surgery evaluated the results of surgical and medical management in 3521 patients between December, 1980, and July, 1983. At admission, 75% of patients were in good neurological condition and surgery was performed in 83%. At the 6-month evaluation, 26% of the patients had died and 58% exhibited a complete recovery. Vasospasm and rebleeding were the leading causes of morbidity and mortality in addition to the initial bleed. Predictors for mortality included the patient's decreased level of consciousness and increased age, thickness of the subarachnoid hemorrhage clot on computerized tomography, elevated blood pressure, preexisting medical illnesses, and basilar aneurysms. The results presented here document the status of management in the 1980's.

Adolescent↗
PubMedDate not supplied

Delay in referral of patients with ruptured aneurysms to neurosurgical attention.

Aneurysmal subarachnoid hemorrhage is a neurosurgical emergency. Early medical intervention is axiomatic for minimizing rebleeding and ischemia from vasospasm and achieving optimum results. The purpose of this study was to document the length and causes of the delay in referral which occur in patients following aneurysmal subarachnoid hemorrhage. The case histories of 150 consecutive patients admitted to The University of Iowa with proven ruptured aneurysms were studied. Medical records from The University of Iowa and referring hospitals were reviewed, and patients, families, and referring physicians interviewed. Overall, only 36% were referred within 48 hours of their first clear cut, recognizable sign or symptom of subarachnoid hemorrhage. Median time to referral was 3.6 days. Delay was due to physician diagnostic problems in 37%, delayed referral policy in 23%, unstable patient condition in 7%, failure of patients to recognize severity of illness in 8%, and logistical reasons in 12%. These data suggest that a large proportion of patients have a delay in achieving definitive neurosurgical care following aneurysm rupture, and that for the most part this delay is avoidable. More emphasis must be placed on public health and primary physician education regarding subarachnoid hemorrhage.

Diagnostic Errors↗