Biomedical subjects

J Morton

Publications and source records attributed to J Morton.

At least 55 records · Page 3Linked to original sources

PubMed2000

Thirty years of universal home dialysis in Christchurch.

AIM: To review 30 years of universal home dialysis in a single dialysis unit. METHOD: Analysis for patients using home dialysis since 1969 of information from hospital visits, clinical case notes and demographic and survival data from the Australia and New Zealand Dialysis and Transplant Registry. RESULTS: Since 1969 treatment options at the Christchurch Nephrology Unit for patients with end-stage renal disease have been home haemodialysis (HD), renal transplantation and, since 1979, continuous ambulatory peritoneal dialysis (CAPD). No long-term, hospital-based treatment has been offered. During this time 493 patients, aged 3-82 years, began treatment. The mean training time for home HD was 79 days (range 23-268) and for home CAPD 7 days (range 1-35). The mean HD treatment time was 7 hours x 3 per week (range 10-36 hours/week). Between 1980 and 1995, less than 5% of patients took antihypertensive drugs and 73% of those aged 18-65 years were in full or part-time employment. The mean age of patients commencing treatment increased from 41.8 years in the 1970s to 50.1 years in the 1990s. The median patient survival from 1970-1997 was 7.75 years on home HD and 2.1 years on home CAPD. Median survival on dialysis fell in the 1990's as more diabetics and older patients with comorbidity started treatment. CONCLUSIONS: Home HD allows good rehabilitation, long treatment times and good blood pressure control which may all contribute to the superior survival of home versus hospital HD. CAPD survival in Christchurch was worse than HD, but this is probably due to patient selection. A policy of universal home dialysis is still workable provided there are sufficient resources for training and support of patients in the community.

Adolescent↗

PubMed2000

Human tooth movement in response to continuous stress of low magnitude.

Conventional orthodontic therapy often uses force magnitudes in excess of 100 g to retract canine teeth. Typically, this results in a lag phase of approximately 21 days before tooth movement occurs. The current project was undertaken to demonstrate that by using lower force magnitudes, tooth translation can start without a lag phase and can occur at velocities that are clinically significant. Seven subjects participated in the 84-day study. A continuous retraction force averaging 18 g was applied to 1 of the maxillary canines, whereas a continuous retraction force averaging 60 g was applied to the other. The magnitude was adjusted for each canine to produce equivalent compressive stresses between subjects. Estimated average compressive stress on the distal aspect of the canine teeth was 4 kPa or 13 kPa. The moment-to-force ratios were between 9 and 13 mm. Tooth movement in 3 linear and 3 rotational dimensions was measured with a 3-axis measuring microscope and a series of dental casts made at 1- to 14-day intervals. The results showed a statistical difference in the velocity of distal movement of the canines produced by the 2 stresses (P =.02). The lag phase was eliminated and average velocities were 0.87 and 1.27 mm/month for 18 and 60 g of average retraction force. Interindividual velocities varied as much as 3 to 1 for equivalent stress conditions. It was concluded that effective tooth movement can be produced with lower forces and that because loading conditions were controlled, cell biology must account for the variability in tooth velocities measured in these subjects.

Adolescent↗

PubMed2000

Metabolic abnormalities associated with skeletal myopathy in severe anorexia nervosa.

The aim of this study was to characterize the metabolic disturbance associated with the skeletal myopathy resulting from extreme weight loss in anorexia nervosa. Muscle function was examined in eight female patients with severe (40%) weight loss due to anorexia nervosa and histologically confirmed myopathy. A wide range of biochemical and hematologic investigations were carried out, including serum enzymes and the response of plasma lactate to ischemic exercise of forearm muscles. All patients showed proximal muscular weakness. A diminished lactate response to ischemic exercise was a consistent finding, and a reduction of serum carnosinase activity was also found. There were no other consistent biochemical or hematologic abnormalities apart from lymphopenia of no clinical consequence. These findings contribute to our understanding of severe protein-energy malnutrition on the musculoskeletal system. The resulting disorder is a metabolic myopathy from which the patients recover rapidly as their nutrition improves. Although the patients admitted to a variety of abnormal eating behaviors, no correlation was found between a specific type of abnormal eating behavior and subsequent biochemical abnormalities. Reinstating appropriate eating behavior will treat the myopathy.

Adolescent↗

PubMed2000

Diagnosis and management of subdural haematoma complicating bone marrow transplantation.

Subdural haematoma (SDH) is a known complication of bone marrow transplantation (BMT). A retrospective review of 657 consecutive patients undergoing allogeneic or autologous bone marrow/stem cell transplantation at the Royal Brisbane Hospital between January 1991 and December 1998 is reported. Seventeen cases of subdural haematoma/hygroma were identified (2.6%). Eleven of these (65%) were bilateral. Four required surgical drainage, with two developing re-accumulation of SDH. All cases presented with a headache and eight of these had associated neurological complications. Diagnosis was made predominately by CT scan: however in 25% of cases definitive diagnosis could only be made in MRI studies. An association with intrathecal methorexate-containing conditioning therapy, post lumbar puncture headache, prolonged thrombocytopenia and coagulopathy was noted. In our experience, conservative management with platelet support and correction of coagulopathy achieved resolution of subdural haematoma in most cases, with surgical intervention being reserved for neurological deterioration. Bone Marrow Transplantation (2000) 25, 549-552.

Adolescent↗

PubMed2000

Fas-independent apoptosis in T-cell tumours induced by the CD2-myc transgene.

Depending on the cellular context, the Myc oncoprotein is capable of promoting cell proliferation or death by apoptosis. These observations suggest that apoptosis in response to deregulated gene expression may represent a natural brake to tumour development. The pathways by which Myc induces apoptosis are as yet poorly characterised although recent observations on rat fibroblasts over-expressing Myc have demonstrated a requirement for the Fas pathway. To investigate the role of Fas in Myc-induced lymphomagenesis we backcrossed CD2-myc mice onto an lpr background. Rates of tumour development and phenotypic properties, including levels of apoptosis were indistinguishable from CD2-myc controls. Further, tumour cell lines derived from mice expressing a regulatable form of Myc showed inducible apoptosis at similar rates regardless of their lpr genotype. These results show that activation of c-myc and loss of Fas do not collaborate in T lymphoma development and that Myc-induced apoptosis in T-cells occurs by Fas-independent pathways.

Animals↗

PubMed2000

A quality assurance review of outpatient care of children with life-threatening asthma exacerbations.

OBJECTIVES: A hospital admission for asthma represents an opportunity to address and improve asthma control. The aims of this study were to compare the ambulatory care of children admitted to the intensive care unit (ICU) following a life-threatening asthma exacerbation with published guidelines of asthma management and to identify areas that could be targeted for change. METHODS: A retrospective review of case notes of children admitted to the ICU with asthma over a 6-month period. Variables recorded were: demographic; asthma history (including prior pattern of asthma, hospital admissions, interval treatment and managing doctor); admission details (consultation of respiratory team and asthma educator); and discharge management. RESULTS: There were 40 admissions of 38 children (24 males) with mean age 5.7 years (range 1.1-14 years). The majority (58%) had previous admissions for asthma (55 admissions in 22 children), with 23% of these to ICU. Sixty three per cent of those with previous admissions had persistent asthma, but only 29% were on inhaled corticosteroid (ICS). Most (60%) were managed by their local medical officer (LMO). Use of ICS was more likely if managed by a paediatrician. A respiratory subspecialist was consulted in 42% and the asthma educator in 70% of ICU admissions. Discharge medication included ICS in 74%, with no interval treatment in 18% of admissions. Follow up was by a respiratory subspecialist in 25% of cases. CONCLUSION: Asthma management before and after admission with life-threatening asthma did not conform to available guidelines. Persistent asthma was under-treated. Paediatricians were more likely to use interval treatment than LMO. We identified areas in which quality of care and outcome could be improved in this vulnerable group of asthmatics.

Ambulatory Care↗

PubMed2000

Depression: the forgotten diagnosis among hospitalized adults.

Depression, one of the most frequent of all medical disorders, is an illness that often concomitantly occurs with many other diseases in hospitalized adult patients. Sadly, overwhelming evidence suggests that comorbid depression is commonly misdiagnosed, undertreated, or not diagnosed at all when present in critically ill patients. While safe, modern, and cost-effective treatments are available for treating this disorder, comorbid depression remains a silent and unseen illness adversely affecting patient outcomes. With an understanding that this pernicious underlying illness frequently exists in hospitalized adults, nurses can identify the symptoms and patterns of comorbid depression, thereby being extremely effective in decreasing the morbidity and mortality that often accompanies this forgotten diagnosis.

Adult↗

PubMed2000

Stress, depression, and psychoneuroimmunology.

Stress is a common phenomenon most people encounter every day, whereas depression represents a vast constellation of mental disorders of multifarious etiology. Both situations have been exhaustively evaluated and scrutinized in the complex field of psychoneuroimmunology (PNI). PNI studies have attempted to ascertain and define the extensive links among and intricate web of neural activity, the endocrine system, and altered immune responses in stressed patients and those with depressive disorders. Although the literature indicates some type of relationship exists between these systems, the associations between and relevance of immune alterations in depression and stress to health and illness remain to be determined. Only by seeking to expand our knowledge of these neurological, endocrine, and immunological alterations in depressed and stressed neurological patients will our understanding of stress, depression, and health be magnified and our ability to provide holistic care be maximized.

Depressive Disorder↗

PubMed2000

Lessons from a comprehensive clinical audit of users of psychiatric services who committed suicide.

OBJECTIVE: Characteristics of patients who committed suicide were examined to provide a picture of the treatment they received before death and to determine whether and how the suicides could have been prevented by the service system. METHODS: The unnatural-deaths register was matched to the psychiatric case register in the state of Victoria in Australia to identify suicides by people with a history of public-sector psychiatric service use who committed suicide between July 1, 1989, and June 30, 1994. Data on patient and treatment characteristics were examined by three experienced clinicians, who made judgments about whether the suicide could have been prevented had the service system responded differently. Quantitative and qualitative data were descriptively analyzed. RESULTS: A total of 629 psychiatric patients who had committed suicide were identified. Seventy-two percent of the patients were male, 62 percent were under 40 years old, and 51 percent were unmarried. They had a range of disorders, with the most common being schizophrenia or schizoaffective disorder (36 percent). Sixty-seven percent had previously attempted suicide. A total of 311 patients (49 percent) received care within four weeks of death. Twenty percent of the suicides were considered preventable. Key factors associated with preventability were poor staff-patient relationships, incomplete assessments, poor assessment and treatment of depression and psychological problems, and poor continuity of care. CONCLUSIONS: Opportunities exist for the psychiatric service system to alter practices at several levels and thereby reduce patient suicides.

Adult↗

PubMed2000

Size makes a difference: use of a low-prime cardiopulmonary bypass circuit and autologous priming in small adults.

Low hematocrit (Hct < 20) during cardiopulmonary bypass (CPB) is associated with higher mortality and other adverse outcomes. More frequently, low Hct is encountered in patients with small body size and women patients. This prompted us to take an aggressive approach in our care of these patients, involving a strategy for predicting patients at risk of low Hct, with the aid of an electronic worksheet that accurately predicts CPB Hct, and two prevention strategies: use of a low-prime CPB circuit (LP) for all adult patients with a body surface area (BSA) < 1.7 m(2) and use of autologous circuit priming (AP), in addition to the low-circuit volume in some patients. The two cohorts of patients in whom these techniques were employed were compared to a group matched for body size where our standard adult circuit (STD) was used. There were 233 patients in the standard group, 139 in the LP group, and 68 in the LP/AP group. The CPB circuit prime volume was 1,710 ml for the STD group and 1,110 ml for the LP group. Use of autologous priming techniques further reduced the prime volume by 545 +/- 139 ml. The incidence of low Hct (<20%) during CPB was thus reduced from 70% to 15% (p = 0.001) when using both techniques together without increasing red blood cell (RBC) transfusions. These changes in perfusion management resulted in a reduction in the incidence of renal complications (STD = 9.4%, LP = 6.5% (ns) and LP/AP = 0%,

Adult↗

PubMed2000

The European Donor Hospital Education Programme (EDHEP): enhancing communication skills with bereaved relatives.

Intensive care medical and nursing staff self-rate their communication skills as improved following attendance at the European Donor Hospital Education Programme (EDHEP) workshop. A prospective study was conducted to determine what impact EDHEP has on communication skills. Doctor-nurse pairs from 10 experimental and 10 control Intensive Care Units undertook two standardized simulated relative encounters (Breaking Bad News and Donation Request) at three measurement points (pre, post and follow-up). Nurses showed no change in communication skills. Experimental group doctors showed significant improvement in breaking bad news and requesting donation; most of these improvements were not maintained. Control group doctors showed some improvement in breaking bad news, indicating that participating in measurement by itself initiates some transient change in communication skills. Attendance at EDHEP does lead to significant improvement in some, but not all, communication skills essential in breaking bad news and requesting donation. Further research is necessary to determine what factors additional to EDHEP will contribute to enduring change in these particular skills.

Adult↗

PubMed2000

The timing, triggers and qualities of recovered memories in therapy.

OBJECTIVES: To report descriptive data on memory recovery of traumatic material including: degree of prior amnesia, triggers to recovery, qualities of the memory and length of time taken to recover different types of memory. DESIGN: British Psychological Society practitioners who reported having clients with recovered memories in a previous large-scale survey were contacted for an indepth interview. They each provided information on up to three such clients. METHODS: From telephone interviews with 108 therapists, we elicited 236 detailed accounts of clients recovering a traumatic memory. Interviews were semistructured with investigator-based ratings. RESULTS: The degree of amnesia varied widely according to therapists: some clients had prior total amnesia, others a prior vague sense or suspicion, and others prior partial memories. Time in therapy before first recall was longer for memories involving child sexual abuse than for memories of other traumas. The majority of the memories, but not all, were similar to those reported by patients with post-traumatic stress disorder: they were fragmented, accompanied by high levels of emotion, and experienced as a reliving of the original event. CONCLUSIONS: On the basis of current understanding of memory processes, several mechanisms may be needed to explain all the data, including disruptions to the encoding and retrieval of traumatic events and errors in the attribution of the source of specific memories. It will be important to confirm these findings by interviewing clients themselves.

Adult↗

PubMed2000

Critical care bug team: a multidisciplinary team approach to reducing ventilator-associated pneumonia.

BACKGROUND: Ventilator-associated pneumonia rates in the medical-surgical intensive care unit first exceeded the 90th percentile in September 1997 and were significantly (P <.05) higher than National Nosocomial Infections Surveillance System pooled mean data. In January 1998, a multidisciplinary "Critical Care Bug Team" was developed by the Infection Control Committee to review 1997 National Nosocomial Infections Surveillance System data for four adult intensive care units in a 583-bed tertiary care hospital. METHODS: Membership included clinical nurse specialists, a dietitian, a pharmacist, a respiratory therapist, an infection control professional, a research specialist, and a physician adviser. Having the team report directly to the hospital's Infection Control and Adult Critical Care Committees maximized support for recommendations and provided a direct link from patient care to hospital administration. By identifying issues, evaluating patient care processes, performing literature searches, and monitoring compliance, the team implemented numerous interventions, including policy and procedure changes, purchasing of equipment, and implementation of various education tools. RESULTS: Each member of the Critical Care Bug Team contributed to a synergized effort that may have produced the desired outcome of decreasing ventilator-associated pneumonia rates. Except for August 1998, ventilator-associated pneumonia rates have been below the 75th percentile since May 1998. CONCLUSION: This study illustrates the effectiveness of a multidisciplinary team approach devised to reduce and stabilize ventilator-associated pneumonia rates in a medical-surgical intensive care unit.

Adult↗

PubMed1999

Pulling smarties out of a bag: a Headed Records analysis of children's recall of their own past beliefs.

The work reported provides an information processing account of young children's performance on the Smarties task (Perner, J., Leekam, S.R., & Wimmer, H. 1987, Three-year-olds' difficulty with false belief: the case for a conceptual deficit. British Journal of Developmental Psychology, 5, 125-137). In this task, a 3-year-old is shown a Smarties tube and asked about the supposed contents. The true contents, pencils, is then revealed, and the majority of 3-year-olds cannot recall their initial belief that the tube contained Smarties. The theoretical analysis, based on the Headed Records framework (Morton, J., Hammersley, R.J., & Bekerian, D.A. 1985, Headed records: a model for memory and its failures, Cognition, 20, 1-23), focuses on the computational conditions that are required to resolve the Smarties task; on the possible limitations in the developing memory system that may lead to a computational breakdown; and on ways of bypassing such limitations to ensure correct resolution. The design, motivated by this analysis, is a variation on Perner's Smarties task. Instead of revealing the tube's contents immediately after establishing the child's beliefs about it, these contents were then transferred to a bag and a (false) belief about the bag's contents established. Only then were the true contents of the bag revealed. The same procedure (different contents) was carried out a week later. As predicted children's performance was better (a) in the 'tube' condition; and (b) on the second test. Consistent with the proposed analysis, the data show that when the computational demands imposed by the original task are reduced, young children can and do remember what they had thought about the contents of the tube even after its true contents are revealed.

Child, Preschool↗

PubMed1999

Carnitine levels in patients with skeletal myopathy due to anorexia nervosa before and after refeeding.

OBJECTIVE: To assess the role of carnitine in the skeletal myopathy present in anorexia nervosa. METHOD: Serum levels of free and total carnitine were measured in a group of severely underweight women with anorexia nervosa and skeletal myopathy before and after an inpatient refeeding program. RESULTS: Carnitine levels were within the reference range before refeeding and remained unchanged despite significant weight gain in all the subjects. CONCLUSION: These findings suggest that carnitine plays no part in the muscle weakness seen in severe anorexia nervosa.

Adult↗

PubMed1999

Participants' judgements of the European Donor Hospital Education Programme (EDHEP): an international comparison.

The European Donor Hospital Education Programme (EDHEP) is a one-day workshop, aimed at providing guidelines for breaking the news of the death of a relative and for raising the issue of organ donation with bereaved relatives. Participants' judgements of the workshop in the Netherlands and in the United Kingdom were compared to determine whether EDHEP meets doctors' and nurses' training needs in breaking bad news and requesting organ donation. In both countries EDHEP appears to be greatly appreciated by intensive care medical and nursing staff; the judgements are more positive in the United Kingdom than in the Netherlands. It seems that, irrespective of their professional experience, intensive care staff consider EDHEP a valuable teaching programme that increases confidence in communicating with bereaved relatives about death and organ donation.

Attitude of Health Personnel↗

PubMed1999

Safe mobilization of normal progenitors in advanced chronic myeloid leukemia with intensive chemotherapy and granulocyte-colony stimulating factor.

Twenty-one patients with advanced chronic myeloid leukemia (late chronic phase (n = 8), accelerated phase (n = 11) and blast crisis (n = 2)) were treated with idarubicin, cytarabine, and etoposide followed by G-CSF and subsequent collection of peripheral blood progenitor cells in the early recovery phase. Treatment was reasonably well tolerated with no deaths or intensive care admissions. Despite the advanced phase of disease and heavy pretreatment with cytotoxics and interferon-alfa, 11 of 21 patients (52%) achieved a cytogenetic response. Of the nine major cytogenetic responses (complete (n = 3) and partial (n = 6)), seven achieved adequate progenitor collections for consideration for autologous transplantation. The only predictor of response was disease duration (P = 0.02). With a median follow-up of 1171 days from treatment it appears unlikely that G-CSF contributed to disease progression. Survival post-IcE was predicted by disease stage (P = 0.0001). Intensive chemotherapy followed by G-CSF allowed adequate yields of predominantly Philadelphia chromosome negative progenitor cells to be obtained from one-third of patients with advanced CML.

Adult↗

PubMed1999

Preverbal, Early Verbal Pediatric Pain Scale (PEPPS): development and early psychometric testing.

The Pre-Verbal, Early Verbal Pediatric Pain Scale (PEPPS) is conceptualized to measure the established pain response in toddlers, a pediatric group void of pain assessment scales. It consists of seven categories, each with weighted indicators. Scores can range from 0 to 26. Using a blinded, cross-sectional design, 40 children, aged 12 to 24 months, were videotaped throughout their postoperative stay in the postanesthesia care unit. Vignettes were randomly selected and viewed by four experienced pediatric nurses. Results indicated that the PEPPS was easy to use and demonstrated acceptable inter-rater and intrarater reliability. Early evidence of construct validity was established by statistically significant differences in premedication and postmedication pain scores.

Child Development↗