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T Bradley

Publications and source records attributed to T Bradley.

At least 37 records · Page 2Linked to original sources
PubMed1995

A model for recording the microcirculatory changes associated with standardized electrical injury of skeletal muscle.

The rate of major limb amputation following high voltage electrical injury remains high despite a decrease in mortality rate. Several theories about the pathophysiology of electrical injury have been discussed in the literature and different clinical regimens have been attempted to decrease the high amputation rate. However, to date, the overall tissue response after electrical injury remains incompletely understood with nothing new to offer these unfortunate patients. We have developed a rat gracilis muscle intravital microscopy preparation in order to better understand the mechanisms of this injury. A standardized 40-V stimulation of 10-sec duration was applied to the anterior belly of the gracilis muscle which translated into a current load of 30 mA. The current density was 750 mA/cm2. Sequential intravital assessment of microcirculatory changes before injury, as well as 5, 15, 30, 60, 120, 180 and 240 min after injury was performed. Consistent findings included initial cessation of blood flow in many capillary beds, focal flow reversal, venous and arterial vascular spasm. Restitution of microvascular flow varied from several minutes to 1 hr and was preceded by vasodilation at 5-15 min following the injury (+16.9 microns from baseline at 15 min). Starting at 30 min progressive vasoconstriction was noted (-0.8 micron from baseline at 30 min, -31.3 microns from baseline at 4 hr). High resolution observation of neutrophil behavior showed an increase in the number of these cells adherent to venular endothelium in areas exhibiting circulatory disturbances (+11.4 cells at 5 min, +15 cells at 4 hr). The standardization of this model allows a quantitative method of evaluating the microcirculatory changes associated with electrical injury and of studying ways to prevent tissue damage. The microcirculatory changes induced by electrical injury were similar to those reported in ischemia-reperfusion injury of skeletal muscle.

Animals↗
PubMed1995

Electrical injuries--morbidity, outcome and treatment rationale.

Electrical injuries are unique with respect to low mortality rates, but very high rates of short- and long-term morbidity, and overall outcome. Controversy still exists regarding the advantages of one-stage debridement versus early serial debridement of necrotic tissue. The purpose of this study was a retrospective evaluation of treatment, morbidity and outcome in a group of patients with electrical injuries. Over a 13-year period 1992 patients were admitted with acute burns to our burn centre. Electrical injuries occurred in 129 (6.5 per cent) of these patients. There were 38 high-tension injuries and 91 low-tension injuries. The average age was 33.7 years (5 months to 63 years), with burn wounds ranging from 1 to 57 per cent total body surface area (mean 9.5 per cent). Ninety-four (72.9 per cent) of these injuries were work related, and most occurred in males (85 per cent). A total of 323 surgical procedures were performed on those 129 patients. An average of 0.48, surgical debridements per patient was necessary in the low-tension injury group and only three partial finger or toe amputations were necessary. In the high-tension group, 27 major limb amputations were performed after 2.3 debridements per patient, resulting in an overall major limb amputation rate of 35 per cent. The average length of stay was 22 days, and the cost of hospitalization ranged from $900 to $120 000 (mean !4,901). Significant long-term neurological deficits persisted in 73 per cent of patients at long-term follow-up (mean 4.5 years). Only 5.3 per cent of patients after high-voltage electrical injury were able to return to their premorbid job.

Adolescent↗
PubMed1995

Toxic epidermal necrolysis: a review and report of the successful use of Biobrane for early wound coverage.

Toxic epidermal necrolysis (TEN), is an exfoliative dermatological disorder of unknown cause. A patient with TEN loses epidermis in sheet-like fashion, leaving extensive areas of denuded dermis that must be treated like a large, superficial, partial-thickness burn wound. Methods of coverage described in the English literature over the last decade include the use of several dressings such as fresh-frozen or cryopreserved cadaver allograft, porcine xenograft, and amnionic membrane. Successful use of the biosynthetic dressing, Biobrane, has been described after burn injuries and Stevens-Johnson syndrome; however, its use in TENS has not. We present three patients with TEN treated successfully in our burn center over the past 12 months using Biobrane. The patients were men aged 20, 58, and 77 years, with 58% to 95% total body surface area slough. Diagnosis was confirmed by skin biopsy on admission, and drug ingestion was implicated in each instance. Each patient was thoroughly debrided in the operating room shortly after admission, and denuded areas were covered with Biobrane within 24 to 48 hours of admission. Biobrane demonstrated greater than 90% adherence by 48 hours, and no wound sepsis occurred. Each patient demonstrated epithelialization within 9 days. Patients were ambulatory at 72 hours. Corticosteroids and prophylactic antibiotics were avoided. Enteral nutritional support and aggressive septic surveillance was routine. Hospital stay was between 13 and 30 days without mortality. Early use of Biobrane in patients with TEN appears to provide a reasonable means of wound coverage.

Adult↗
PubMed1995

Folic acid prescription in pregnancy.

We resolved to prescribe folic acid supplements for all women who attended this practice during the first twelve weeks of pregnancy. Six months after this decision a prescription was recorded in only 13% of cases: this compared with 18% during the two months immediately following the decision. It was resolved to improve this performance and observations six months later revealed a prescription recorded in 63% of cases. Subsequently a new form for recording an antenatal consultation was devised and six months after its implementation, 100% recording of folate prescription for appropriate cases was observed. It was concluded that these simple audit exercises prompted changes in practice which helped to improve standards of patient care.

Adolescent↗
PubMed1995

Paediatric consultation patterns in general practice and the accident and emergency department.

The age, sex, source of referral and diagnosis of children brought to a paediatric accident and emergency department by their parents were compared to those consulting their general practitioner. A simultaneous, prospective review of these consultations was carried out over a six-week period in an inner-city paediatric teaching hospital and a group practice in a socially deprived urban area. 730 children less than 13 years of age who presented for a new consultation were seen. 629 (86%) presented initially to the general practitioner, who dealt with all but 25 (4.0%) without onward referral to the accident and emergency department. 127 consultations took place at the accident and emergency department, of which 104 (82%) were parental referrals. There was no sex difference in children seen by the general practitioner. There was a decreasing trend with increasing age in the proportion of children who consulted the general practitioner, perhaps due to the higher frequency of injury in the older children. Over three quarters (77%) of injured children were brought directly to the accident and emergency department, compared with only 4% of children without injuries (p < 0.001). Of 22 children with injuries who presented to the general practitioner, only 4 (18%) required onward referral. General practitioners met the great majority of the paediatric workload generated by the practice. Audit between primary and secondary care gives a more reliable picture than data from only one source. Injured children are more likely to be taken to the accident and emergency department. Further study of the severity of injury in children is required to determine if there is potential to reduce parental referrals to accident and emergency departments.

Child↗
PubMed1994

Use of glycerolized human allografts as temporary (and permanent) cover in adults and children.

Multiple efforts to achieve immediate and complete burn wound closure following early debridement have been attempted to prevent septic complications, and to decrease the morbidity and mortality associated with major burns. The BG University Hospital Bergmannsheil Bochum (BGUBB) Burn Centre admitted 157 patients with deep partial thickness and full thickness skin burns during 1991 and 1992. Twenty-eight of these patients (18 per cent) were treated with glycerolized human allografts. A total of 57 allograft transplantations were performed on these 28 patients. Our indications for the use of glycerolized human allografts, as well as our results, are presented and discussed.

Adolescent↗
PubMed1991

del(2)(p23): a consistent recurrent abnormality in acute myelogenous leukemia.

A case of acute myelogenous leukemia (AML-M2) with an unusual chromosomal finding is presented. In addition to the most frequently observed translocation in this neoplasia, involving the long arms of chromosomes 8 and 21, there was a partial deletion of the short arm of chromosome 2 band (p23), i.e., 46,XX,del(2)(p23),t(8;21)(q22;q22). Deletion of the short arm of chromosome 2 has been described in association with other chromosome abnormalities in two other cases of AML and as the sole abnormality in three cases of AML, indicating that this abnormality is nonrandom and may be associated with leukemic transformation of hematopoietic cells. Therefore, we propose that the del(2)(p23),t(8;21)(q22;q22) abnormality be accorded status III and possibly considered a subset of AML (M2).

Adult↗
PubMed1991

Prognostic indicators for the development of AIDS in HIV antibody positive haemophiliac patients: results of a three-year longitudinal study.

In February 1986, 40 out of 75 adult patients with haemophilia A attending St. James's University Hospital were human immunodeficiency virus (HIV) antibody positive. Over a three-year period these patients were prospectively studied with regard to possible prognostic indicators for the development of the acquired immune deficiency syndrome (AIDS). Using the Centres for Disease Control (CDC) classification of HIV infection, 17 patients (42.5%) developed group 4 disease during this time, giving an actuarial three-year progression rate of 44%, and 5 patients (12.5%) died. The following parameters measured at recruitment were found independently to predict progression to AIDS: a serum beta 2-m level of greater than 3.5 mg/l, (chi 2 = 15.95, P less than 0.001), a serum IgA level of greater than 4.5 milligram(s) (chi 2 = 6.08, P less than 0.02) and p24 antigenaemia (chi 2 = 5.7, P less than 0.05). The actuarial three-year progression rate in those patients abnormal by two or more of these parameters was 100% (n = 7), compared to only 7% in patients who were normal by all three values (n = 15). CD4+ lymphocyte counts and CD4+:CD8+ ratios were significantly lower in HIV positive compared with HIV negative patients (P less than 0.01), but did not predict the development of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Hypertrophy of renal mitochondria.

Compensatory renal hypertrophy leads to an increase in the size and metabolic capacity of renal tubular cells. Increased transport and metabolic activities must be sustained by an augmented rate of energy production, which is largely dependent on mitochondrial processes. Although previous studies have suggested that mitochondria proliferate in the hypertrophying cell, the data to support this have not been convincing. This study was designed to determine whether the mitochondria of the hypertrophied renal proximal tubular cell undergo hypertrophy or proliferation. Flow cytometric analysis of proximal tubular cells obtained from the kidneys of uninephrectomized rabbits revealed an increase in cell size and RNA content compared with control cells but showed no change in DNA content and nuclear size and no evidence of entry into the S/G2/M phases of the cell cycle. Histomorphometric analysis of cortical proximal tubules revealed that although cytoplasmic volume increased, mitochondrial density remained constant, indicating that mitochondrial volume increases in proportion to the increase in cell volume. By day 14, mitochondrial volume had increased 66% above control values. Electron microscopic examination of isolated S2 proximal tubules from 5/6 nephrectomized rabbits with maximal hypertrophy revealed mitochondrial cristae which appeared to be more densely packed than that in normal cells. The size of the functional mitochondrial pool per cell was determined by rhodamine-123 fluorescence. This increased within 24 h of uninephrectomy, peaked at approximately 80% above control levels at 5 days, and remained elevated throughout the 16 days of observation. The initial increase (days 1 and 2) occurred before a measurable increase in mitochondrial volume occurred and presumably reflects an increase in mitochondrial membrane potential.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Catecholamine measurements in urine by high-performance liquid chromatography with amperometric detection--comparison with an autoanalyser fluorescence method.

In order to validate different methods of measuring urinary catecholamines (norepinephrine, epinephrine and dopamine) in humans, methods based on separation of catecholamines using reversed-phase or cation-exchange high-performance liquid chromatography with electrochemical detection were compared with an autoanalyser-based fluorescence method. Different methods for pre-chromatography sample purification were also studied. For measurements of urinary catecholamines, the reversed-phase-based chromatographic techniques studied were found to give less reliable results than cation-exchange chromatography, even if one of them (Clin Rep Urine Catecholamine Kit) gave almost as precise estimates. The autoanalyser technique yielded good results. It is concluded that cation-exchange chromatography with an appropriate sample work-up procedure (a combination of organic solvent extraction and alumina adsorption) is a reliable and accurate method for analyses of urinary catecholamines.

Acetates↗