Utilization of preoperative cerebrospinal fluid drain in skull base surgery.

OBJECTIVE: Retrospectively assess the efficacy of lumbar cerebrospinal fluid (CSF) drainage placed preoperatively in skull base operations in decreasing the incidence of postoperative CSF fistula. METHODS: A retrospective review of 150 patients undergoing a posterior fossa craniotomy from 1989 to 2000 was conducted. Patients were divided into those receiving preoperative lumbar drains and those that did not. The rates of postoperative CSF leakage were compared between the two groups. Patient data were analyzed to determine if there were other comorbidities affecting the postoperative incidence of CSF leakage such as smoking, diabetes, or hypertension. RESULTS: Between 1989 and 1994, 25/72 (35%) patients with no preoperative lumbar drain had a postoperative CSF leak. From 1995 to 2000, 9/78 (12%) patients with a preoperative lumbar drain had a CSF leak. This was a 23% decreased incidence of postoperative CSF leakage and a significant decrease in the probability (p < 0.001) of CSF leakage in patients treated with a preoperative lumbar drain. The comorbidities of diabetes, smoking, or hypertension did not increase the probability of a CSF leak (p = 0.43). CONCLUSIONS: A preoperatively placed lumbar drain can significantly lower the rate of postoperative CSF leakage after skull base surgery. The drain is a well-tolerated adjunct to dural closure and helps increase surgical exposure of the posterior fossa. The comorbidities of diabetes, smoking, or hypertension do not contribute to an increased rate of CSF leakage.dagger Lyal Leibrock M.D., F.A.C.S. is Deceased.     

Factors Affecting the In Vivo Lactone Stability and Systemic Clearance of the Lipophilic Camptothecin Analogue AR-67

Purpose  

The narrow efficacy-toxicity window of anticancer agents necessitates understanding of factors contributing to their disposition. This is especially true for camptothecins as they exist in the lactone and carboxylate forms with each moiety differentially interacting with efflux or uptake transporters. Here we determined the disposition of the lactone and carboxylate forms of AR-67, a 3^rd generation camptothecin analogue.     

Infantile hypertrophic pyloric stenosis: where should it be treated?

A retrospective analysis in the form of an audit into the management of infantile hypertrophic pyloric stenosis in a district general hospital has revealed that the results are equivalent to that of published data from specialised units. It is stressed in this study that close co-operation has to be maintained between paediatricians and surgeons in the care of these infants. The diagnosis can be made on clinical grounds in the majority of cases. The operation has to be carried out by experienced surgeons and anaesthetists. The morbidity can be minimised under these circumstances and pyloromyotomy can be performed safely in a district general hospital.     

Correct positioning for cardiac angiography: Insights from mri

The recommended angiographic projections for optimally demonstrating various cardiac structures vary, and do not always achieve their aim. To determine the most appropriate radiographic projections to optimally demonstrate cardiac structures, we reviewed the orientations of major cardiac structures and the associated great vessels, as demonstrated by axial MRI. Measurements were made from 187 MRI examinations of the heart. These measurements confirmed that the optimum angiographic projections for various cardiac structures are at variance with a number of the recommended views. Recommendations for the angiographic projections most likely to provide optimum display of various cardiac structures and associated great vessels in different patient populations are presented. © 1993 Wiiey-Liss, Inc.     

Evaluation of monoclonal anti-D reagents using D variant cells

Monoclonal anti-D antibodies submitted to the Third Monoclonal International Workshop were evaluated against a number of D variant cells using standard serological techniques. The monoclonal antibodies were able to discriminate between the cells of Categories Va, VI and DFR but not Category III cells. Cells within each category did not give any aberrant results. The Rh:33 cells behaved as normal Rh(D) positive cells.     

Immunohistochemical localization of tissue factor pathway inhibitor-1 (TFPI-1), a Kunitz proteinase inhibitor, in Alzheimer''s disease

Senile plaques in Alzheimer's disease (AD) are composed principally of Aβ, a 4 kDa fragment of the amyloid precursor protein (APP). Longer forms of APP which contain a Kunitz proteinase inhibitor (KPI) domain are elevated in aged and in AD brains. Tissue factor pathway inhibitor-1 (TFPI) contains three tandem KPI domains and has been well characterized for its role as a natural anticoagulant in the extrinsic coagulation pathway. Functionally, the first two KPI domains of TFPI bind and inhibit the activity of factor Xa and VIIa respectively. In addition, TFPI and APP-KPI share a common clearance mechanism through the low density lipoprotein receptor-related protein (LRP). As part of an ongoing study of the role of KPI-containing proteins in AD, the current study examines TFPI localization in the brain. We report here that TFPI is immunohistochemically localized to microglia in both AD and non-AD individuals and is localized to some senile plaques in AD. Western blot analyses indicate that the amount of TFPI is elevated in frontal cortex samples from AD brains. We propose that TFPI may play a cell specific role in proteinase regulation in the brain.     

Relationship between refractive error and monochromatic aberrations of the eye.

PURPOSE: To examine the relationship between ametropia and optical aberrations in a population of 200 normal human eyes with refractive errors spanning the range from +5.00 to -10.00 D. METHODS: Using a reduced-eye model of ametropia, we tested the hypothesis that the optical system of the eye is uncorrelated with the degree of ametropia. These predictions were evaluated experimentally with a Shack-Hartmann aberrometer that measured the monochromatic aberrations across the central 6 mm of the dilated pupil in well-corrected, cyclopleged eyes. RESULTS: Optical theory predicted, and control experiments on a model eye verified, that Shack-Hartmann measurements of spherical aberration will vary with axial elongation of the eye even if the dioptric components of the eye are fixed. Contrary to these predictions, spherical aberration was not significantly different from emmetropic eyes. Root mean square of third-order aberrations, fourth-order aberrations, and total higher aberrations (third to 10th) in myopic and hyperopic eyes were also uncorrelated with refractive error. Astigmatic eyes tended to have larger total higher-order aberrations than nonastigmatic eyes. CONCLUSIONS: We conclude that a reduced-eye model of myopia assuming fixed optical parameters and variable axial length is not tenable.     

What Are the Etiology and Epidemiology of Out‐of‐hospital Pediatric Cardiopulmonary Arrest in Ontario,Canada?

Background: Pediatric cardiopulmonary arrest (CPA) outside of the hospital has a very high mortality rate. Objectives: To evaluate the etiology and initial compromise of pediatric CPA cases in hopes of developing strategies to improve out‐of‐hospital resuscitation. Methods: The Ontario Prehospital Advanced Life Support (OPALS) study was a large multicenter initiative to evaluate the impact of emergency medical services (EMS) programs on 17 communities with 40,000 critically ill and injured patients who were older than 11 years. As part of this study, the authors conducted a retrospective observational cohort study that included all children younger than 18 years of age with out‐of‐hospital CPA, during an 11‐year period from 1991–2002. CPA was defined as patient being pulseless, apneic, and requiring chest compressions. Data were collected from ambulance call reports and centralized dispatch data and were reviewed by two independent investigators. Results: There were 503 children with CPA in the sample. Mean age was 5.6 years (range, 0–17 yr); 58.4% of patients were male, and 37.8% were younger than 1 year of age. Cardiopulmonary resuscitation (CPR) first was started by a bystander in 32.4% of cases, whereas 66.0% were unwitnessed arrests. Initial rhythms were asystole 77.2% of the time, pulseless electrical activity 16.4% of the time, and ventricular fibrillation or ventricular tachycardia 4% of the time. Annual incidence was 9.1/100,000 children. CPA was witnessed in 34.0% of cases; 80.7% of these were bystander‐witnessed, and 18.1% were EMS‐witnessed. Primary pathogenic cause of arrest was medical in 61.2% of cases, trauma in 37.2% of cases, and indeterminate in 1.6% of cases. Initial underlying physiologic compromise of witnessed arrests was judged to be respiratory in 39.8% of cases, sudden collapse (presumed electrical) in 16.4% of cases, progressive shock in 1.2% of cases, and indeterminate in 42.6% of cases. Presumed etiology was trauma, 37.6%; sudden infant death syndrome (SIDS), 20.3%; and respiratory disease, 11.6%, most commonly. Survival to hospital discharge was 2.0%. Conclusions: This is one of the largest population‐based, prospective cohorts of pediatric CPA reported to date, and it reveals that most pediatric arrests are unwitnessed and receive no bystander CPR. Those that are witnessed most often are caused by respiratory arrests or trauma. Trauma, SIDS, and respiratory disease are the most common etiologies overall. These data are vital to planning large resuscitation trials looking at specific interventions (i.e., increasing bystander CPR) and highlight the need for better strategies for prevention and early recognition.