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Biomedical subjects

J Morgan

Publications and source records attributed to J Morgan.

At least 109 records · Page 6Linked to original sources

The use of a back class teaching extension exercises in the treatment of acute low back pain in primary care.

BACKGROUND: Back extension exercises are commonly recommended to treat acute low back pain. Evidence of their beneficial effect is, however, weak. OBJECTIVES: We aimed to demonstrate a benefit of teaching back extension exercises in addition to usual GP care for acute low back pain. METHODS: Patients with acute simple low back pain of less than 28 days duration, presenting to a GP, were randomized either to attend a back class or to receive conventional management. Outcome was measured using changes in the Oswestry disability score and visual analogue pain scale (VAS) on six occasions during 1 year and also a VAS and patient assessment of degree of disability during the previous 6 months at 1 year. RESULTS: Seventy-five patients were recruited. The principal outcome measures showed no difference between the two groups. The treatment group reported less chronic disability at 1 year (50% versus 14%, P < 0.007). CONCLUSIONS: A treatment effect has not been demonstrated, but some patients who would otherwise have reported mild pain were pain free after 1 year. This approach to treating back pain has not been shown to be effective. More much larger studies, with more intensive treatment, are required in order to decide whether physical therapy in primary care is beneficial as treatment for acute back pain.

Acute Disease↗

Validation of air as an equilibration medium in gastric tonometry: an in vitro evaluation of two techniques for measuring air PCO2.

This laboratory-based bench study was undertaken to evaluate the accuracy and equilibration characteristics of air and saline respectively as CO2 equilibrating media in the silicone balloon of a gastric tonometer and to compare two methods of measuring air PCO2. Two gastric tonometers were suspended in a bath containing 0.9% saline maintained at 37 degrees C. Certified calibration gases at three different CO2 concentrations were bubbled into the bath. When the bath PCO2 measurement was stable the tonometers were primed with 5 ml of air and 2.5 ml normal saline respectively and allowed to equilibrate for 30 and 90 minutes. Following equilibration, samples were aspirated and analysed in duplicate in a blood gas analyser. Bias and precision were calculated from the measured and expected PCO2 values. A consistent negative bias (21-23%) was seen with air at all three CO2 concentrations at 30 and 90 minutes with a coefficient of variation between 2.7 and 3.3%. Imprecise data were obtained with saline at different levels of CO2. A similar experimental set-up was used to compare air PCO2 measurement by a blood gas analyser and an infra-red analyser (Tonocap). Similar bias was obtained with the blood gas analyser with respect to air PCO2 measurement as in experiment 1. The infra-red analyser measurement was highly precise with negligible bias. Air appears to be a better CO2 equilibration medium during bench testing of tonometry producing a systematic negative offset and requiring a uniform correction factor of 1.25. This correction factor is independent of equilibration time and equilibrating CO2 concentration. The use of the infra-red analyser eliminates any bias in the measurement of air PCO2 and obviates the need for a correction factor.

Air↗

Constitutional WT1 mutations in Wilms' tumor patients.

PURPOSE: Patients with Wilms' tumors (WT) who carry constitutional mutations in the WT1 gene have been described in case reports and small case series. We sought to determine the frequency of constitutional WT1 mutations in a larger cohort, and to identify clinical manifestations associated with the risk for carrying a WT1 mutation. METHODS: We collected clinical data and blood samples from 201 patients with a history of WT. Southern blot analysis, single-strand conformation polymorphism (SSCP) analysis, and direct DNA sequencing were performed on DNA isolated from peripheral-blood lymphocytes from each patient. Odds ratios (ORs) for the carriage of a germline mutation of the WT1 gene were calculated for patients who had specific clinical risk factors compared with those who did not. RESULTS: Of 201 patients with WT in the cohort, eight patients were carriers of mutations in the WT1 gene. Six of the eight mutations were protein-truncating nonsense mutations. None of 56 patients with isolated unilateral WT was a carrier. The OR of carrying a WT1 mutation was elevated for patients with genitourinary anomalies (OR19.3; P < .002). Seven of 28 boys with WT with cryptorchidism carried WT1 mutations. No increased risk was observed for patients with nephrogenic rests, bilateral tumors, history of secondary cancers, or family history of WT. CONCLUSION: Germline WT1 mutations in patients with WT are associated with genitourinary anomalies, especially cryptorchidism and/or hypospadias. Patients with WT and no genitourinary anomalies are at low risk for carrying a WT1 mutation. Constitutional WT1 mutations that encode truncated WT1 proteins may predispose to the development of cryptorchidism, hypospadias, and WTs.

Adolescent↗

Gestational changes in the levels of transforming growth factor-beta1 (TGFbeta1) and TGFbeta receptor types I and II in the human myometrium.

As term approaches, a number of key proteins [contraction-associated proteins (CAPs)] are expressed within the human myometrium that are essential for the activation of powerful coordinated contractions during labor. The nature of the signals that switch on the synthesis of CAPs in vivo is not known. The ryanodine-sensitive intracellular Ca2+ release channel (RyR2) is a CAP whose expression in vitro is activated by transforming growth factor-beta (TGFbeta). The present experiments were performed to determine whether TGFbeta and TGFbeta receptors are present in the human myometrium at term and to explore the idea that they might form part of a signaling system in vivo. TGFbeta receptor types I and II, but not III, were demonstrated in myometrial smooth muscle in tissue taken from nonpregnant, pregnant nonlaboring, and spontaneous laboring women. Western blotting was used subsequently to determine the relative expression of TGFbeta receptor types I and II. Using nonpregnant myometrium as a baseline control the levels of expression of receptor types I and II were significantly increased by 168 +/- 19% (n = 6) and 162 +/- 22% (n = 7) in pregnant nonlaboring myometrium. In spontaneous laboring myometrium the levels of TGFbeta receptor type I and II expression were 93 +/- 12% (n = 6) and 85 +/- 11% (n = 7), respectively, compared to nonpregnant control values and were significantly lower than levels in pregnant nonlaboring tissues. The total TGFbeta1 levels in the myometrial tissues were 334 +/- 10, 534 +/- 73, and 674 +/- 106 pg/g tissue wet wt in nonpregnant, pregnant nonlaboring, and spontaneous laboring myometrium (n = 3 in each group), respectively. Thus, the TGFbeta signaling system appears to be up-regulated in the myometrium before the onset of parturition. The apparent loss of receptors in the spontaneous laboring samples in the presence of elevated total levels of TGFbeta may be indicative of agonist-induced receptor down-regulation. These observations support the idea that cytokines, in particular TGFbeta1, may play a role in the normal processes that prepare the myometrium for parturition at term.

Blotting, Western↗

Near-infrared spectroscopy in the assessment of cerebral oxygenation at high altitude.

Hypoxia plays a key role in the pathogenesis of acute mountain sickness (AMS), but individual susceptibility is variable and cerebral symptoms do not always correlate with PaO2 measurements. Cerebral hypoxia may be more relevant than PaO2. We studied trends in cerebral regional oxygen saturation by the technique of near-infrared spectroscopy in 20 subjects ascending rapidly to 4680 m. Subjects were enrolled in a placebo-controlled, double-blind trial of medroxyprogesterone for the prevention of AMS. The fall in cerebral oxygen saturation was less than in the periphery. At 4680 m, cerebral oxygenation correlated with peripheral saturation but not with PaCO2 or with cerebral symptoms scores. At 4680 m, subjects on medroxyprogesterone had higher cerebral and peripheral saturation compared with those on a placebo. We conclude that cerebral oxygenation monitored with the Critikon 2020 system provided important information on the complex relationship of hypoxia to AMS and that other factors, such as changes in blood flow or capillary permeability, may be equally important.

Adult↗

GRP78 induction by calcium ionophore potentiates photodynamic therapy using the mitochondrial targeting dye victoria blue BO.

The cationic photosensitizing triaryl methane dye Victoria Blue BO (VBBO) localizes in mitochondria and causes oxidative damage to this organelle during photodynamic therapy (PDT). Oxidative stresses from other photosensitizers induce a variety of stress proteins. The endoplasmic reticulum (ER)-based, calcium-binding stress protein GRP78 is a putative protective factor for photosensitizers such as Photofrin that damage multiple intracellular sites and for several cytotoxic agents. In the current study VBBO-PDT was found to induce glucose-regulated protein (GRP)78. However, in contrast to other drugs, rather than being protected, human squamous carcinoma cells (FaDu) induced to express GRP78 by calcium ionophore A23187 became more sensitive to PDT. A line of Chinese hamster ovary cells (C-1) constitutively overexpressing GRP78 also were more sensitive. Cytotoxicity of the A23187 treatment and VBBO was synergistic, with more than 11-fold potentiation with light irradiation, but was only additive in the dark. The increased cell killing was not due to differences in VBBO uptake or to changes in the intracellular localization of VBBO caused by calcium ionophore or GRP78. Thus, GRP78 appears to enhance rather than protect against VBBO-induced mitochondrial photodamage and contributes to cell death. This novel finding possibly may stem from the effects of GRP78, ER Ca2+ stores and ATP consumption on the Ca2+ and ATP-dependent mitochondrial permeability transition that may be evoked by PDT damage to the mitochondrial respiratory chain. The work suggests interventions that may potentiate PDT with mitochondrial targeting sensitizers and potential enhancements in efficacy when GRP78 is upregulated biologically or pharmacologically.

Animals↗

Early undifferentiated connective tissue disease. V. An inception cohort 5 years later: disease remissions and changes in diagnoses in well established and undifferentiated connective tissue diseases.

OBJECTIVE: To review the diagnoses after 5 years in patients who were identified within 12 months of the onset of well established and undifferentiated connective tissue diseases (CTD); to examine death rates and disease remissions in these patients. METHODS: This inception cohort of 410 patients was identified in 10 academic rheumatology practices. They had less than one year of signs and/or symptoms of CTD. Diagnoses of specific well established CTD were made using accepted diagnostic and classification criteria. The diagnoses after 5 years were determined. RESULTS: Patients with well established CTD tended to remain with the original diagnosis. The progression of unexplained polyarthritis to rheumatoid arthritis occurred infrequently. Ten percent of patients with isolated Raynaud's phenomenon progressed to systemic sclerosis (SSc). The 5 year survival was over 90% in all diagnostic categories, with the exception of SSc, in which it was 64%. CONCLUSION: Patients with a well established CTD usually continued with the same diagnosis. Patients with undifferentiated CTD tended to remain undifferentiated or to remit.

Arthritis↗

Characterization of endogenous protoporphyrin IX induced by delta-aminolevulinic acid in resting and activated peripheral blood lymphocytes by four-color flow cytometry.

Lymphocytes treated with delta-aminolevulinic acid (ALA) can accumulate the photoactive, fluorescent heme precursor, protoporphyrin IX (PpIX). With visible light illumination, PpIX can be used in photodynamic therapy (ALA-PDT) to kill or functionally alter cells. The aim of this study was to characterize the effects of ALA and ALA-PDT on resting and activated human peripheral blood T lymphocytes. Accumulation of PpIX depends inversely on the rate of its iron-dependent conversion into heme. Activated replicating lymphocytes have low intracellular iron levels, with corresponding increases in the transferrin receptor (CD71). Thus, we expected activated lymphocytes would preferentially accumulate PpIX. Using four-color flow cytometry, we examined ALA-induced PpIX levels in T-cell subsets of resting and activated human peripheral blood mononuclear cells and the relationship between CD71 and PpIX. Peripheral blood mononuclear cells stimulated by phytohemagglutinin (PHA) were simultaneously phenotyped for PpIX, CD71 and the T-cell markers CD3 and CD4 or CD8. In activated cells treated with 0-6 mM ALA for 4 h, PpIX fluorescence was maximal at 1 mM ALA. On a single cell basis, there was a strong correlation between PpIX accumulation and CD71 expression. The ALA-treated, PHA-stimulated, CD71+ lymphocytes had an eight-fold greater mean PpIX fluorescence than nonactivated, CD71- cells. Approximately 87% of the CD4+ and 85% of the CD8+ T cells accumulated PpIX. The PpIX levels of CD8+ cells were about 5% greater than CD4+ cells. In addition, mixed lymphocyte reaction-stimulated cells treated with ALA accumulated more PpIX than controls. Thus, activated cells preferentially accumulate endogenous PpIX when exogenous ALA is administered. Cytotoxicity studies showed that the majority of the activated cells following ALA-PDT were killed but resting cells were spared. Also, in examining activation markers by flow cytometry the number of cells that were positive for activation markers CD38 or CD71 dramatically decreased after ALA and light treatment in activated populations. The data suggest a role for ALA-PDT as an immunomodulator or photocytotoxic agent targeting activated lymphocytes.

Aminolevulinic Acid↗

Analysis of anti-Trypanosoma cruzi antibody isotype specificities by western blot in sera from patients with different forms of Chagas' disease.

Infection of humans with Trypanosoma cruzi leads to either a lifelong asymptomatic infection or to symptomatic presentations such as cardiomyopathy, mega-syndromes, or both. The reasons for the different clinical manifestations are not understood. We have previously studied a group of chronically infected individuals with different clinical forms of Chagas' disease and found that the levels of some anti-T. cruzi antibody isotypes, analyzed by enzyme-linked immunosorbent assay, differed among patients with different clinical presentations. We have expanded these studies to examine the antigen specificity of these patients' IgG1, 2, 3, IgM, and IgA by western blot. We observed that binding of particular antigens by some antibody isotypes were more prevalent in some clinical groups as compared to others. For example, IgG3 from 13 of 19 (68%) individuals with digestive manifestations bound a 68-kDa antigen, but only 3 of 31 (9%) individuals with cardiac involvement detected this same moiety. We also found that, regardless of the clinical group, the profiles of antigens recognized by each antibody isotype differs dramatically from the profiles recognized by each other isotype. Together with our previous observations demonstrating that the levels of anti-parasite antibody isotypes correlates with the clinical form, these data suggest that overall anti-T. cruzi antibody reactivities may indeed be skewed toward different antigens in individuals with different clinical presentations.

Adult↗

Evaluation of mitomycin-treated vero cells as a co-culture system for IVM/IVF-derived bovine embryos.

Support of the in vitro development of IVM/IVF-derived bovine embryos by Vero cells was evaluated by comparing the following treatment groups: 1) proliferating (Unt-Vero) vs nonproliferating (Mit-Vero) cells; 2) supplementation of medium with estrous cow serum (ECS) vs bovine serum albumin (BSA); 3) Mit-Vero cells vs bovine oviduct epithelial cells (BOECs); and 4) addition of leukemia inhibitory factor (LIF) to Mit-Vero cell co-cultures at Day 1 vs Day 4. Mit-Vero cells stimulated higher rates of blastocysts (Day 7, 40 vs 27%) and hatched blastocyst (Day 10, 38 vs 12%) formation than Unt-Vero cells. These rates were comparable to those obtained with BOECs; blastocyst hatching was slightly higher following co-culture with Mit-Vero cells (36%) than BOECs (29%). Blastocyst formation was similar in ECS- vs BSA-supplemented medium; however, hatching was greatest (37%) during co-culture in medium +10% ECS. While the addition of LIF throughout the co-culture period was ineffective, addition of the cytokine beginning at Day 4 slightly increased blastocyst formation rates. Evaluation of LIF secretion using ELISA revealed detectable levels of the cytokine in Mit-Vero-conditioned medium (50 pg/10(5) cells); this may explain the minimal influence of exogenous LIF during embryo co-culture. Mit-Vero cells provided comparable support of bovine embryo development when used even up to 2 wk after establishment as monolayers. In conclusion, Mit-Vero cells provide a readily-available, safe and easy-to-use co-culture method which is at least as supporting of bovine embryo development as BOECs. One contribution of these cells may be secretion of the cytokine LIF.

Journal Article↗

Prediction of early death in end-stage renal disease patients starting dialysis.

Demand for dialysis for patients with end-stage renal disease is growing, as is the comorbidity of dialysis patients. Accurate prediction of those destined to die quickly despite dialysis could be useful to patients, providers, and society in making decisions about starting dialysis. To determine whether age and comorbidity accurately predict death within 6 months of first dialysis for end-stage renal disease, a prospective cohort study of 822 patients starting dialysis at one of 11 Canadian centers was performed. Patient characteristics were recorded at first dialysis. Follow-up continued until death or study end (at least 6 months after enrollment). One hundred thirteen of 822 (13.7%) patients died within 6 months. Although an existing scoring system predicted prognosis, adverse scores greater than 9 were found in only 9.7% of those who died; only 52% of those who scored higher than 9 died within 6 months. No score cutoff point combined high true-positive and low false-positive rates for predicting early death. Age, severity of heart failure or peripheral vascular disease, arrhythmias, malnutrition, malignancy, or myeloma were independent prognostic factors identified in multivariate models. However, the best fit discriminant and logistic models were also unable to accurately predict death within 6 months. Clinicians were very accurate in assigning patients to prognostic groups up to a 50% risk of death by 6 months, above which they tended to overestimate risk. However, clinicians were only marginally better than the predictive models in determining whether a given high-risk patient would die. The inability of a scoring system or clinical intuition to accurately predict death soon after starting dialysis for end-stage renal disease suggests that limiting access to dialysis on the basis of likely short survival may be inappropriate in Canada.

Aged↗

Electrophysiological effects of E 4031, a drug with selective class III properties, in man.

We studied the electrophysiological effects of E 4031, given in a dose ascending manner (1.5, 3.0, and 6.0 micrograms/kg over 5 min followed by 0.1, 0.2, and 0.4 microgram/kg per min for 60 min, respectively) to 19 volunteers. There were significant, dose related linear increase in QT and QTc intervals, in atrial functional and effective refractory periods (ERPs) at a paced cycle length of 400 ms, and in ventricular functional and ERPs at a paced cycle length of 600 ms. There was no significant change in the AH and HV intervals or QRS duration. No significant proarrhythmic or other side effects were encountered during the administration of the drug. E 4031 prolongs atrial and ventricular refractoriness without significantly affecting AV or intraventricular conduction, consistent with selective Class III properties. At the doses used in the present study, intravenous infusion of E 4031 appears to be safe and well tolerated.

Adolescent↗

Micrometastases: marker of metastatic potential or evidence of residual disease?

BACKGROUND: Micrometastases within bone marrow have been shown to indicate a poor prognosis in patients with epithelial tumours. However, the degree to which micrometastases represent true residual disease or cell shedding and metastatic potential, is unclear. AIM: To explore whether micrometastases represent residual disease, bone marrow taken from carefully staged patients before and after (> 6 months) "curative" resection of a primary gastrointestinal cancer was studied prospectively. PATIENTS/METHODS: Seventy two consecutive patients were studied; the only exclusions were patients with known overt metastatic disease at the time of surgery. Micrometastatic cells were quantified per 10(5) marrow cells by flow cytometry after staining for contaminant cytokeratin-18 positive cells. RESULTS: Micrometastases were detected preoperatively in 22% (16/72) of all patients, comprising 11 (23%) of 48 with colorectal cancer, five (33%) of 15 with gastric adenocarcinoma and none (0%) of nine with oesophageal squamous cancer. Although fewer metastatic cells were detected in postoperative bone marrow, and clearance of marrow deposits was evident in most patients, the persistence of micrometastases in five of 16 patients after resection, without evidence of tumour recurrence, indicates a subset with true residual disease. Detection of micrometastases postoperatively (persistent or newly developed) was significantly associated with development of overt metastases during the subsequent 12-18 months of follow up (nine of 19 patients) when compared with patients testing negative for micrometastases (eight of 53; p < 0.01). CONCLUSIONS: Preoperative detection of micrometastases may reflect either transient shedding of cells, metastatic potential or residual disease, but postoperative micrometastases indicate minimal residual disease. Identification of these patients is important because they may benefit from adjuvant therapy.

Biomarkers, Tumor↗

A prospective, randomized comparison of an in-line heat moisture exchange filter and heated wire humidifiers: rates of ventilator-associated early-onset (community-acquired) or late-onset (hospital-acquired) pneumonia and incidence of endotracheal tube occlusion.

PURPOSE: To compare the performance of an in-line heat moisture exchanging filter (HMEF) (Pall BB-100; Pall Corporation; East Hills, NY) to a conventional heated wire humidifier (H-wH) (Marquest Medical Products Inc., Englewood, Colo) in the mechanical ventilator circuit on the incidence of ventilator-associated pneumonia (VAP) and the rate of endotracheal tube occlusion. METHODS: This report describes a prospective, randomized trial of 280 consecutive trauma patients in a 20-bed trauma ICU (TICU). All intubated patients not ventilated elsewhere in the medical center prior to their TICU admission were randomized to either an in-line HMEF or a H-wH in the breathing circuit. Ventilator circuits were changed routinely every 7 days, and closed system suction catheters were changed every 3 days. HMEFs were changed every 24 h, or more frequently if necessary. A specific endotracheal tube suction and lavage protocol was not employed. Patients were dropped from the HMEF group if the filter was changed more than three times a day or the patient was placed on a regimen of ultra high-frequency ventilation. The Centers for Disease Control and Prevention (CDC) criteria for diagnosis of pneumonia were used; early-onset, community-acquired pneumonia was defined if CDC criteria were met in < or =3 days, and late-onset, hospital-acquired pneumonia was defined if criteria were met in >3 days. Laboratory and chest radiograph interpretation were blinded. RESULTS: The patient ages ranged from 15 to 95 years in the HMEF group and 16 to 87 years in the H-wH group (p=not significant), with a mean age of 46 years and 48 years, respectively. The male to female ratio ranged between 78 to 82%/22 to 18%, respectively, and 55% of all admissions were related to blunt trauma, 40% secondary to penetrating trauma, and 5% to major burns. There was no difference in Injury Severity Score (ISS) between the two groups. Moreover, there was no significant difference in mean ISS among those who did not develop pneumonia and those patients who developed either early-onset, community-acquired or late-onset, hospital-acquired pneumonia. The HMEF nosocomial VAP rate was 6% compared to 16% for the H-wH group (p<0.05), and total ventilator circuit costs (per group) were reduced. There were no differences in duration of ventilation (mean+/-SD) if the patient did not develop pneumonia or if the patient developed an early-onset, community-acquired or a late-onset, hospital-acquired pneumonia. Moreover, total TICU days were reduced in the HMEF group. In addition, the incidence of partial endotracheal tube occlusion was not significantly different between the H-wH and the HMEF groups. CONCLUSIONS: The HMEF used in this study reduced the incidence of late-onset, hospital-acquired VAP, but not early-onset, community-acquired VAP, compared to the conventional H-wH circuit. This was associated with a significant reduction in total ICU stay. Disposable ventilator circuit costs in the HMEF group were reduced compared to the H-wH group in whom circuit changes occurred at 7-day intervals. CLINICAL IMPLICATIONS: The use of the HMEF is a cost-effective clinical practice associated with fewer late-onset, hospital-acquired VAPs, and should result in improved resource allocation and utilization.

Adolescent↗

Oral administration of tylosin phosphate for treatment and prevention of proliferative enteropathy in pigs.

OBJECTIVE: To evaluate the efficacy of orally administered tylosin phosphate for prevention and treatment proliferative enteropathy (PE) in pigs. ANIMALS: Crossbred pigs weaned at 24 days of age. PROCEDURE: Pigs were challenge exposed with an inoculum of Lawsonia intracellularis strain LR189/5/83. Seven control pigs received buffer solution. Of 33 challenge-exposed pigs, 8 were untreated. Two groups of challenge-exposed pigs were dosed orally with tylosin phosphate via a 2% stabilized premix, starting with 100 or 40 ppm 4 days before challenge exposure and continuing for 16 days, when the dose was reduced to 40 or 20 ppm, respectively, which was continued for 12 more days. Another group of challenge-exposed pigs was dosed orally with 100 ppm of tylosin phosphate commencing 7 days after challenge exposure and continuing for 21 days. Pigs were euthanatized and necropsied 4 weeks after challenge exposure. RESULTS: The 8 untreated pigs had reduced weight gain, 3 of them had moderate diarrhea 3 weeks after challenge exposure. Five pigs had gross lesions of PE at necropsy. Seven pigs had histologic lesions of PE with numerous L intracellularis organisms. None of the pigs in the control, nonchallenge-exposed, or the 3 groups given tylosin phosphate before or after challenge exposure had clinical signs or lesions of PE. CONCLUSION AND CLINICAL IMPLICATIONS: Tylosin phosphate can be effective for prevention and for treatment of PE, using reported dosing schedules. We can experimentally induce PE, using the pure culture challenge-exposure model, for use in testing of treatments.

Administration, Oral↗

Subarachnoid hemorrhage in the African-American population: a cooperative study.

The clinical outcome of patients following subarachnoid hemorrhage is complicated by delayed cerebral ischemia and contributing factors such as hypertension. To observe the impact of hypertension and delayed cerebral ischemia on the outcome of a predominantly African-American cohort following subarachnoid hemorrhage, both retrospective (n = 42) and prospective (n = 21) studies were conducted. In the total pool (n = 63), the mean age was 49.7 years (range: 17 to 80) with a preponderance of female patients (70%). Aneurysm formation was significant in the region of the posterior communicating artery. Of the patients reviewed, 73.8% had preexisting hypertension and 45.9% developed delayed cerebral ischemia. Approximately 89% of the patients who suffered from delayed cerebral ischemia had hypertension. Results failed to display any significant beneficial association between the use of the calcium channel blocker nimodipine and delayed cerebral ischemia. Use of the antifibrinolytic drug aminocaproic acid demonstrated a worse patient outcome. It is not recommended that aminocaproic acid be used in this population. Subsequently, due to the proportional occurrence of delayed cerebral ischemia in hypertensive patients following subarachnoid hemorrhage, it is suggested that prophylactic surgical management of unruptured intracranial aneurysms be considered in hypertensive patients. Further study is needed to discern the association between hypertension, delayed cerebral ischemia, and stroke in patients following subarachnoid hemorrhage.

Aminocaproates↗