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D Cass

Publications and source records attributed to D Cass.

32 records · Page 2Linked to original sources
PubMed1998

Determining appropriateness of coronary thrombolysis in the emergency department.

STUDY OBJECTIVE: To estimate the appropriateness of decision-making by emergency physicians regarding coronary thrombolysis. METHODS: We conducted a retrospective chart review of patients admitted over a period of 13 months from a tertiary care center emergency department with a diagnosis of an acute ischemic coronary syndrome. Both thrombolysed and nonthrombolysed patients were eligible for inclusion. The decisions of emergency physicians to use or not use thrombolytics were compared with standard Canadian guidelines, based on the blinded assessments of two reviewers. Appropriateness was estimated with the use of adjusted kappa statistics, and a hierarchical statistical model was developed to estimate the distribution of appropriate decision-making rates for individual emergency physicians. RESULTS: The overall adjusted kappa for appropriateness was .85 (95% confidence interval [CI], .76 to .94). The appropriateness rate for thrombolysed patients was 80.6% (95% CI, 62.5 to 92.5), and for nonthrombolysed patients it was 97.2% (95% CI, 91.9 to 99.4). The distribution of individual emergency physician appropriateness rates had an estimated mean of 91.3% and a 95% CI of 81.3% to 97.7%. Complication rates were not significantly different from previously published rates. CONCLUSION: This study demonstrates excellent agreement between emergency physicians' decisions regarding thrombolysis and standard Canadian guidelines, based on an adjusted kappa statistic. The distribution of individual emergency physician appropriateness rates and the appropriateness rate for nonthrombolysed patients are estimated for the first time.

Adult↗
PubMed1998

A dinucleotide mutation in the endothelin-B receptor gene is associated with lethal white foal syndrome (LWFS); a horse variant of Hirschsprung disease.

Lethal white foal syndrome (LWFS) is a congenital anomaly of horses characterized by a white coat colour and aganglionosis of the bowel, which is similar to Hirschsprung disease (HSCR). We decided to investigate possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as recent studies in mutant rodents and some patients have demonstrated EDNRB defects. First, we identified a full-length cDNA for horse EDNRB . This cDNA fragment contained a 1329 bp open reading frame which encoded 443 amino acid residues. The predicted amino acid sequence was 89, 91 and 85% identical to human, bovine and mouse as well as rat EDNRB respectively, but only 55% identical to the human, bovine and rat endothelin A receptor (EDNRA). Secondly, sequence analysis, together with allele-specific PCR and the amplification-created restriction site (ACRS) technique, revealed a dinucleotide TC-->AG mutation, which changed isoleucine to lysine in the predicted first transmembrane domain of the EDNRB protein. This was associated with LWFS when homozygous and with the overo phenotype when heterozygous.

Animals↗
PubMed1997

An overview of the management of electrical storm.

Electrical storm is defined as recurrent, hemodynamically destabilizing ventricular tachycardia or ventricular fibrillation occurring two or more times in a 24 h period, and usually requiring electrical cardioversion or defibrillation. Recent advances in the understanding of the pathogenesis of this serious arrhythmia and in its pharmacological management have improved the prognosis for patients experiencing electrical storm. In this article, several different clinical syndromes of electrical storm and the management of each are examined.

Anti-Arrhythmia Agents↗
PubMed1996

Inactivation of the integrin beta 6 subunit gene reveals a role of epithelial integrins in regulating inflammation in the lung and skin.

The integrin alpha v beta 6 is only expressed in epithelial cells. In healthy adult epithelia, this receptor is barely detectable, but expression is rapidly induced following epithelial injury. Mice homozygous for a null mutation in the gene encoding the beta 6 subunit had juvenile baldness associated with infiltration of macrophages into the skin, and accumulated activated lymphocytes around conducting airways in the lungs. Beta 6-/- mice also demonstrated airway hyperresponsiveness to acetylcholine, a hallmark feature of asthma. These results suggest that the epithelial integrin alpha v beta 6 participates in the modulation of epithelial inflammation. Genetic or acquired alterations in this integrin could thus contribute to the development of inflammatory diseases of epithelial organs, such as the lungs and skin.

Alopecia↗
PubMed1990

Paediatric post-injury management: a hospital-based review of deaths.

In order to begin to evaluate the need for an integrated trauma management service for injured children, a retrospective review of deaths following admission to a suburban teaching hospital was conducted. The medical records and coroners' reports for 64 consecutive cases over 68 months were reviewed, looking for errors in care which may have contributed to fatal outcomes. There was a male predominance (64%). The main causes of death were pedestrian injuries (42%), drownings (20%), injuries to vehicular passengers (17%) and injuries to cyclists (13%). Errors, often multiple, occurred in 29 cases (45%). Errors most frequently involved airway control and ventilatory support (25%), volume replacement (19%) and delays in performing essential investigations (13%). Errors were most frequent at the referring hospitals (49% [17 of/35 referred cases], compared with 14% at the teaching hospital), and principally involved multiply injured victims of blunt trauma (81%, 13 of 16 patients). In only three cases (5%) would better management have salvaged the patient. This can be explained partly by the predominance of what were judged to be irretrievable intracranial injuries (90%) in patients suffering blunt injuries. In contrast, an analysis of the same patient group revealed that in 30-50% the fatality could have been prevented by the full application of well recognized safety strategies. While strategies such as triage and trauma teams should reduce the error rate, it is yet to be proven that optimal post-injury care will significantly reduce mortality.

Adolescent↗
PubMed1990

Aganglionosis: associated anomalies.

In a series of 21 patients with aganglionosis there were five with associated anomalies (24%). These included trisomy 21, Smith-Lemli-Opitz syndrome type II, persistent Müllerian duct syndrome, supernumerary digits and segmental hypopigmentation. This high incidence may be due to sample bias, but clinicians are encouraged to carefully follow their aganglionic patients as there may be under-reporting of associated anomalies. Knowledge of these anomalies can help in the management of individual patients and subsequent pregnancies. In addition these diverse associated anomalies suggest that as well as sometimes being part of a vagal neural crest deficiency, aganglionosis can be part of a generalized mesenchymal defect in embryonic development. There are probably several genes involved.

Abnormalities, Multiple↗
PubMed1988

The management of injuries--a review of deaths in hospital.

A prospective review was undertaken of the management of 111 consecutive patients who died in hospital after admission for treatment of injuries. A standard set of data relating to each patient was reviewed by each member of a trauma death audit committee and then by the whole committee. Autopsy reports were available on all patients. Conclusions were drawn concerning defective aspects of patient management and possible avoidance of each death. Injury severity was assessed using the Trauma Score (TS) and Injury Severity Score (ISS). The possibly avoidable death (PAD) rate was 17%. The most common defects in management were related to inadequate fluid resuscitation and delays in definitive management. The greatest contributions to the PAD rate were from inadequate fluid resuscitation, delays and inadequate perception of the severity of injuries or significance of clinical deterioration. Increasing age was related to a higher frequency of PAD. PAD rate in the presence of severe head injury was 8%, but was 63% in the absence of a severe head injury. It is concluded that review of all trauma deaths is an achievable, beneficial and essential part of a hospital-based integrated trauma service. TS and ISS are not sufficiently sensitive to justify their use in selecting deaths for review. Improved blood volume replacement, earlier and more direct management and supervision by senior specialist staff, and elimination of causes of delay in patient management should all decrease the death rate from injuries particularly in patients without severe head injury.

Adolescent↗
PubMed1987

Identification of risk factors for spinal cord ischemia by the use of monitoring of somatosensory evoked potentials during coarctation repair.

The infrequency of spinal cord infarction and paraplegia after occlusion of the descending thoracic aorta has effectively precluded statistical identification of risk factors. Reversible spinal cord ischemia (SCI), however, is more common, can be detected by intraoperative neurophysiologic monitoring, and can lead to irreversible spinal cord damage. Spinal somatosensory evoked potentials (SEPs) were monitored intraoperatively in 38 patients (18 days to 18 years) undergoing coarctation repair (1982-1986). Although no patients sustained perioperative neurologic dysfunction, 10 of 38 (26%) patients developed reversible SCI, as reflected by greater than 75% loss of SEP N1-P1 interpeak amplitude during aortic occlusion (mean clamp time, 29.1 +/- 1.1 min). During occlusion, seven of 38 (18%) sustained complete loss of the SEP; uniform and prompt (1 to 6 min after clamp release) recovery of the signal occurred in these patients with reperfusion following completion of the repair (n = 6), or temporary institution of partial occlusion (n = 1). By multiple regression analysis the degree of SCI was negatively related to the distal aortic pressure (mean 32.4 +/- 2.4 mm Hg, p = .03), and the occlusion PCO2 (mean 33.1 +/- 1.1 mm Hg; p = .013), and positively related to the change in proximal systolic pressure with aortic occlusion (mean 19.8 +/- 3 mm Hg, p = .003). We conclude that: (1) distal hypotension and SCI commonly occur during aortic occlusion for coarctation repair, and (2) intraoperative interventions that can potentially influence distal aortic perfusion and/or PCO2 should be used judiciously.

Aortic Coarctation↗
PubMed1986

Hirschsprung's disease: an historical review.

A historical review of Hirschsprung's disease is of relevance for several reasons. The historical events are revealing as to how clinical diseases are often slowly unravelled. In addition, many unsolved problems are highlighted. Firstly the exact cause is unknown. There is obviously an interaction between genetic and environmental factors, the nature of which is of interest to basic scientists as well as clinicians. Secondly the pathophysiological explanation for the functional obstruction, and especially its variability, is still incomplete. Much more needs to be known about normal gastrointestinal physiology before this question can be fully answered. Thirdly the technique and timing of operative correction remains inconclusive. Despite extensive postoperative assessment there is no one operation that is clear superior. Each have characteristic problems, but all share the main problem; the abnormal internal sphincter. It remains uncertain how much (if any) of the sphincter should be bypassed. As well the optimal timing of operation is uncertain, with some theoretical advantages being suggested for earlier operation. However, these advantages need to be balanced against possible technical problems. Nevertheless the aim of surgical correction should be the full attainment of normal faecal continence.

Adolescent↗
PubMedDate not supplied

Adrenal response to serial cosyntropin stimulation after repeated high-dose prednisone administration in patients with lymphoma.

To determine if repeated courses of high-dose prednisone given to patients with lymphoma as part of multiple-drug chemotherapy programs would lead to progressive adrenal suppression, serial cosyntropin stimulation tests were performed. Four patients with diffuse histiocytic lymphoma (group 1) received prednisone for 5 days every 3 weeks for five courses, and five patients with Hodgkin's disease (group 2) received prednisone for 14 days every 4 weeks for six courses. Testing was done on Day 1 of each treatment course prior to the administration of therapy and after the final course of chemotherapy. In group 1 patients, there was no evidence of adrenal suppression after any of the courses of prednisone. The plasma cortisol increments after cosyntropin injection were also normal. In the group 2 patients, significant depression of basal plasma cortisol concentrations was observed after the first and fifth courses of prednisone, compared to the pretreatment values. The depression reflected the previous course of prednisone administration only and was not progressive with subsequent courses. The plasma cortisol increments after cosyntropin injection were normal despite depressed basal plasma cortisol levels.

Adrenal Cortex Function Tests↗