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D J Cox

Publications and source records attributed to D J Cox.

At least 19 recordsLinked to original sources

Use of heparinase modified thrombelastography in liver transplantation.

Severe coagulopathies can occur during liver transplantation, particularly after reperfusion of the grafted liver. Heparin release has been proposed as one of the factors contributing to this coagulopathy. We have analysed the thrombelastograph (TEG) traces of 55 patients after reperfusion using native and heparinase-treated samples. In almost all cases an abnormal native TEG was improved in vitro by heparinase, demonstrating the presence of heparin or a heparin-like substance. The heparinase-modified TEG allowed assessment of the underlying coagulation status, providing a rational guide to blood component replacement or treatment of fibrinolysis.

Blood Coagulation Disorders

Lack of correlation of anorectal manometry with symptoms of chronic childhood constipation and encopresis.

UNLABELLED: Chronic constipation is an extremely common problem in children. Many authors have advocated using anorectal manometric examination during evaluation of chronic childhood constipation and encopresis as a means of developing individualized modes of treatment. PURPOSE: This study was designed to prospectively examine frequency and severity of symptoms of childhood constipation and encopresis and associate these symptoms with anorectal manometric findings. METHODS: Forty-four children with chronic constipation participated in the study. Before performing anorectal manometry, bowel-related symptoms were collected for two consecutive weeks with a computerized voice mail system. Anorectal manometry was performed using a triple lumen catheter attached to a hydraulic manometry infusion system. RESULTS: Frequency of voluntary bowel movements did not correlate with any manometric parameters. Frequency of fecal soiling, age at onset of symptoms, and duration of symptoms were all highly correlated with degree of sphincter spasm during attempted defecation; however, none of these variables correlated with any other manometric parameter. Amount of pain associated with bowel movements correlated with frequency of soiling and was inversely correlated with maximum squeeze pressure but was not correlated with any other manometric parameter. CONCLUSIONS: In children with chronic constipation and encopresis, sphincter spasm demonstrated with anorectal manometry is highly correlated with frequency of fecal soiling, age at onset, and duration of symptoms; however, none of the other commonly measured manometric parameters appear to correlate with symptoms of chronic childhood constipation and encopresis.

Age of Onset

Thrombelastographic evaluation of coagulation in transurethral prostatectomy.

OBJECTIVE: To assess the changes in overall coagulation status and define the degree of systemic fibrinolysis occurring in patients undergoing transurethral prostatectomy (TURP). PATIENTS AND METHODS: Thirty patients undergoing TURP, 23 for benign prostatic hyperplasia and seven for prostatic carcinoma, were studied prospectively. Serial venous blood samples were taken using the two-syringe technique. Samples were taken before, during and at intervals up to 72 h and 10-14 days after surgery. Thrombelastography (TEG) was performed on native whole blood samples. Peri-operative blood loss was assessed, until the catheter was removed, by photometric estimation of the haemoglobin content of the irrigant fluid and the measurement of clot volume. RESULTS: There was no evidence of fibrinolysis (TEG Percentage Clot Lysis Ly60 > 15%) in any patient over the whole peri-operative period. There was a significant change in the mean TEG variables towards hypercoagulation from 3 h until 10-14 days postoperatively, compared with the pre-operative values (P < 0.05). There was a significant correlation between blood loss and clot volume. CONCLUSION: These results question the role of systemic fibrinolysis in primary and secondary haemorrhage following TURP and thus the rationale of using antifibrinolytics in these patients. The persistent hypercoagulable state post-operatively indicates a possible role of hypercoagulability in clot retention.

Blood Coagulation

Additive benefits of laxative, toilet training, and biofeedback therapies in the treatment of pediatric encopresis.

Compared the additive benefits of laxative, behavior, and biofeedback treatments for encopresis, while attempting to identify treatment mechanisms and predictors of treatment outcome. 44 encopretic children, ages 6-15 years, were randomly assigned to either laxative therapy (LAX), LAX plus enhanced toilet training (ETT), or LAX + ETT + anal sphincter biofeedback (BF). Daily symptom diaries were completed 14 days before, upon initiation of and 3 months following treatment initiation. ETT and BF were superior to LAX in reducing encopresis. Outcome was significantly predicted by improvement during the initial 14 days of treatment. Reduction of soiling was associated with an increase in bowel movement frequency, and reductions in defecation pain and parental prompting to use the toilet. Because of its efficacy and minimal reliance on technology, ETT should be the initial treatment of choice.

Adolescent

The frequency of severe hypoglycaemia in children with insulin-dependent diabetes mellitus.

The literature contains numerous reports of the frequency of severe hypoglycaemia in childhood insulin-dependent diabetes mellitus. Unfortunately, most of these data have been collected in such a manner as to make comparisons between them difficult. Most reports have used small, well-defined populations of children who were participants in larger, complex, clinical studies. Additional difficulties are encountered in the standardization of the definition of severe hypoglycaemia. Some studies have required that the child lose consciousness while others also included children who required assistance with treatment. Even when studies clearly define the representative nature of their patient population and include universally acceptable criteria for identifying a severe hypoglycaemic episode, the frequency of severe hypoglycaemia must be qualified. Severe hypoglycaemia is generated by a series of complex biological, psychological, and behavioural processes. Its frequency must be viewed not as a fixed value, but rather as a dynamic dependent variable.

Adolescent

Thrombelastography reveals two causes of haemorrhage in HELLP syndrome.

We describe the use of thrombelastography in HELLP syndrome (Haemolysis, Elevated Liver Enzymes, Low Platelets). It differentiated between two possible causes of significant haemorrhage and revealed an accompanying underlying fibrinolysis. This allowed specific therapy to be directed at both abnormalities and, we believe, helped prevent this patient from undergoing radical surgery to curb blood loss.

Adult

Long-term follow-up of medically treated childhood constipation.

We describe the long-term (mean 6.8 years) follow-up of 43 children treated medically for chronic constipation and encopresis. Overall outcome was quite good. Thirty children (70%) were entirely asymptomatic at follow-up. Intermittent mild constipation persisted in 13 patients; only two required persistent but infrequent laxative therapy. Encopresis persisted in three of 17 children who initially reported this symptom, and was associated with significant behavioral problems.

Adolescent

Reduced awareness of hypoglycemia in adults with IDDM. A prospective study of hypoglycemic frequency and associated symptoms.

OBJECTIVE: To prospectively evaluate the frequency and severity of hypoglycemic episodes in IDDM subjects who declare themselves to have reduced awareness of hypoglycemia, to validate their self-designations in their natural environment, and to determine objectively the presence or absence of autonomic and neuroglycopenic symptoms associated with their low blood glucose (BG) levels. RESEARCH DESIGN AND METHODS: A total of 78 insulin-dependent diabetes mellitus (IDDM) subjects (mean age 38.3 +/- 9.2 years; duration of diabetes 19.3 +/- 10.4 years) completed two sets of assessments separated by 6 months. The assessments included reports of frequency and severity of low BG, symptoms associated with low BG, and a BG symptom/estimation trial using a hand-held computer (HHC). Diaries of hypoglycemic episodes were kept for the intervening 6 months. HbA1 levels were determined at each assessment. RESULTS: Of the subjects, 39 declared themselves as having reduced awareness of hypoglycemia (reduced-awareness subjects). There were no differences between these reduced-awareness subjects and aware subjects with regard to age, sex, disease duration, insulin dose, or HbA1. During the HHC trials, reduced-awareness subjects were significantly less accurate in detecting BG < 3.9 mmol/l (33.2 +/- 47 vs. 47.6 +/- 50% detection, P = 0.001) and had significantly fewer autonomic (0.41 +/- 0.82 vs. 1.08 +/- 1.22, P = 0.006, reduced-awareness vs. aware) and neuroglycopenic (0.44 +/- 0.85 vs. 1.18 +/- 1.32, P = 0.004, reduced-awareness vs. aware) symptoms per subject. Prospective diary records revealed that reduced-awareness subjects experienced more moderate (351 vs. 238, P = 0.026) and severe (50 vs. 17, P = 0.0062) hypoglycemic events. The second assessment results were similar to the first and verified the reliability of the data. CONCLUSIONS: IDDM subjects who believe they have reduced awareness of hypoglycemia are generally correct. They have a history of more moderate and severe hypoglycemia, are less accurate at detecting BG < 3.9 mmol/l, and prospectively experience more moderate and severe hypoglycemia than do aware subjects. Neither disease duration nor level of glucose control explains their reduced awareness of hypoglycemia. Reduced-awareness individuals may benefit from interventions designed to teach them to recognize all of their potential early warning symptoms.

Adult

Simple electromyographic biofeedback treatment for chronic pediatric constipation/encopresis: preliminary report.

Pediatric constipation/encopresis is thought to be due, in part, to paradoxical constriction of the external anal sphincter (EAS) muscle during attempted defecation. This inappropriate contraction can lead to delayed, impacted, painful, and infrequent bowel movements. Standard Medical Care (SMC) involves disimpaction with enemas, followed by laxative therapy and diet modification, to maintain frequent soft stools. Using the case control method, the efficacy of SMC alone was compared with SMC plus EAS electromyographic biofeedback aimed at eliminating paradoxical contraction. Thirteen consecutive chronically constipated children received SMC plus biofeedback, and were compared with 13 age- and sex-matched children who received only SMC. Biofeedback subjects demonstrated post-treatment elimination of EAS paradoxical constriction. At 16 months follow-up parents of biofeedback children reported significantly greater improvement in constipation, encopresis, laxative use, and painful bowel movements compared to SMC.

Adolescent

Thermal biofeedback in the treatment of intermittent claudication in diabetes: a case study.

The objective of the present case study was to examine the therapeutic effects of thermal biofeedback-assisted autogenic training on a patient with non-insulin-dependent diabetes mellitus (NIDDM), vascular disease, and symptoms of intermittent claudication. The patient received thermal biofeedback from the hand for five sessions, then from the foot for 16 sessions, while hand and foot skin temperature were monitored simultaneously. In addition, the patient was instructed in autogenic training and practiced daily at home. Follow-up measurements were taken at 12 and 48 months. Within-session foot temperature rose specifically in response to foot temperature biofeedback and starting foot temperature rose between sessions. Posttreatment blood pressure was reduced to a normal level. Attacks of intermittent claudication were reduced to zero after 12 sessions and walking distance increased by about a mile per day over the course of treatment. It would appear that thermal biofeedback and autogenic training are potentially promising therapies for persons with diabetes and peripheral vascular disease.

Biofeedback, Psychology

Behavioral treatment of phobic avoidance in multiple chemical sensitivity.

The clinical ecology model of environmental illness, or multiple chemical sensitivity (MCS), and particularly the theoretical assumptions, diagnostic procedures, and therapeutic recommendations promulgated by clinical ecologists are reviewed. No scientific evidence is found for their claims. MCS is conceptualized, instead, as a phobic disorder explicable in terms of the two-factor model of avoidance. Three cases of MCS are discussed in light of this model, and a comprehensive behavioral treatment package that includes biofeedback-assisted in vivo desensitization and cognitive restructuring is proposed.

Adult

Frequency of severe hypoglycemia in insulin-dependent diabetes mellitus can be predicted from self-monitoring blood glucose data.

Severe hypoglycemia is associated with insulin-dependent diabetes mellitus and may occur more frequently as metabolic control approaches normal. The goal of this study was to determine whether the frequency of severe hypoglycemia could be predicted by the following predictor variables: 1) frequency and degree of low blood glucose (BG) readings, 2) degree of BG variability during routine self-monitoring blood glucose (SMBG) readings, and 3) level of glycemic control measured by glycosylated hemoglobin-A1 (HbA1). Seventy-eight insulin-dependent diabetes mellitus subjects from 3 different sites had their glycosylated HbA1 assayed and then performed 50 SMBG recordings during the next 2-3 weeks. Over the following 6 months, subjects recorded their severe hypoglycemic episodes (stupor or unconsciousness). There was no difference in the number of severe hypoglycemic episodes between subjects in good vs. poor metabolic control. A higher frequency of severe hypoglycemia during the subsequent 6 months was predicted by frequent and extreme low SMBG readings and variability in day to day SMBG readings. Regression analysis indicated that 44% of the variance in severe hypoglycemic episodes could be accounted for by initial measures of BG variance and the extent of low BG readings. Patients who recorded variable and frequent very low BG readings during routine SMBG were at higher risk for subsequent severe hypoglycemia. Individuals who had lower glycosylated Hb levels were not at higher risk of severe hypoglycemic episodes.

Adult

Individual differences in neurobehavioral disruption during mild and moderate hypoglycemia in adults with IDDM.

This study investigated the neurobehavioral effects of mild and moderate hypoglycemia in adults with insulin-dependent diabetes mellitus (IDDM). On 2 consecutive days, 26 subjects were tested in a counterbalanced, randomized, single-blind, crossover design. On the experimental day, subjects performed tests at 6.4, 3.6, and 2.6 mmol/l and again after glycemic recovery to 6.3 mmol/l. On the control day, subjects performed tests four times at euglycemia. Three months after testing, 15 subjects repeated the experimental day protocol. Results demonstrated that both mild and moderate hypoglycemia significantly disrupted performance. However, performance deterioration varied substantially across individual subjects. Men exhibited significantly more deterioration than women at mild hypoglycemia, and subjects with a history of unconsciousness due to hypoglycemia exhibited more deterioration than subjects with no such history. Individual deterioration scores during repeat testing significantly correlated with performance during original testing. Recovery from hypoglycemia-related impairment varied across individuals and was correlated with degree of impairment during hypoglycemia. These results suggest that the glycemic threshold for onset and recovery from neurobehavioral deterioration with hypoglycemia, as well as degree of impairment experienced, varies across individuals. Furthermore, these individual differences are stable across time.

Adult

Long-term follow-up evaluation of blood glucose awareness training.

OBJECTIVE: Blood glucose awareness training (BGAT) has been found effective in teaching individuals with insulin-requiring diabetes to improve their ability to better recognize blood glucose (BG) fluctuations. This study investigated whether subjects who underwent BGAT a mean of 4.9 years previously were superior to past control subjects in terms of their ability to recognize BG fluctuations, and whether past BGAT subjects had fewer automobile crashes and lost work days and better glycosylated hemoglobin than control subjects. Additionally, the beneficial effects of providing booster training to past BGAT subjects also was evaluated. RESEARCH DESIGN AND METHODS: This study followed up 28 past BGAT subjects. Half of these subjects (n = 14) received a simple booster-training program. Twelve previous control subjects also were evaluated. Booster subjects were given a BGAT diary to complete for 2 weeks before evaluation. Evaluation for all subjects included completion of a retrospective questionnaire on work and driving history, blood drawing for a glycosylated hemoglobin analysis, and having subjects estimate and measure their BG levels 50-80 times during a 3- to 4-week period during their daily routine. RESULTS: At long-term follow-up, BGAT subjects had significantly fewer automobile crashes than control subjects. BGAT subjects receiving booster training were significantly more accurate at estimating their BG levels and were more aware of hypoglycemia. Post hoc analyses indicated that the ability to accurately estimate BG fluctuations correlated positively with follow-up glycosylated hemoglobin and the number of hypoglycemic and hyperglycemic symptoms participants demonstrated. Both BGAT and control subjects demonstrated significantly improved glycosylated hemoglobin relative to baseline measures. CONCLUSIONS: These data suggest that BGAT has long-term benefits, which can be enhanced with booster training. Specifically, BGAT and simple booster training may result in reduction of severe hypoglycemic episodes and automobile crashes in the long term.

Accidents, Traffic