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J Wallwork

Publications and source records attributed to J Wallwork.

At least 199 records · Page 11Linked to original sources
PubMed1991

Early abdominal complications following heart and heart-lung transplantation.

In the first 11 years of the heart and heart-lung transplantation programme at Papworth Hospital, Cambridge, 356 patients underwent heart transplantation, and 73 patients received both heart and lungs. Out of 429 patients 41 (9.5 per cent) developed abdominal complications within the first 30 days, and 20 of the 41 required surgery. The complications included pancreatitis (10), peptic ulceration (8), and pseudo-obstruction (8), in addition to colonic perforation and small bowel obstruction. When laparotomy was performed it was well tolerated. This paper supports the view that successful management of abdominal complications following transplantation requires prompt diagnosis and treatment. Where doubt exists in the presence of an acute abdomen, laparotomy is the appropriate way to establish a definitive diagnosis.

Acute Disease↗
PubMed1991

Pulmonary reflexes after human heart-lung transplantation.

Heart-lung transplantation involves denervation of the lungs below the tracheal anastomosis, with associated permanent loss of all pulmonary innervation except post-ganglionic efferent nerves. This is supported by loss of the cough reflex to inhaled USNDW, which also implies that the RARs which mediate this cough mechanism lie in the central airways. Bronchoconstriction following inhalation of USNDW developed only in those HLT recipients with acute lung rejection; this was not related to methacholine responsiveness and may therefore represent a pathologic vascular response. Hyperresponsiveness to methacholine has been reported following HLT, which we found unrelated to inflammation or acute rejection. A similar hyperresponsiveness to histamine was seen, which correlated with the response to methacholine. This also implies that histamine may act directly on smooth muscle receptors, and not solely via a cholinergic reflex. Hyperresponsiveness following HLT may be due to development of a generalized denervation hypersensitivity. Bronchodilation following capsaicin inhalation has been observed in HLT recipients, and may be due to unopposed release of VIP from retained post-ganglionic efferent nerves.

Aerosols↗
PubMed1991

Experience of percutaneous transluminal coronary angioplasty in orthotopic cardiac transplant recipients.

We evaluated the role of percutaneous transluminal coronary angioplasty (PTCA) in a series of orthotopic cardiac transplant recipients with severe epicardial coronary occlusive disease. Ten orthotopic cardiac transplant patients treated by PTCA up to March 1990 were reviewed. All had significant epicardial coronary artery lesions (greater than 70% stenosis compared with the adjacent healthy artery) and exercise electrocardiogram or isotope perfusion evidence of myocardial ischaemia in the relevant region. Primary angiographic PTCA success was achieved in 12 of the 16 lesions attempted (75%). Mean stenosis improvement was from 80% of adjacent healthy artery (range 70-90%) to 12% (range 0-20%). Median angiographic follow-up of 9 months (2-25 months) is available for all patients. The mean recurrence rate is 33% (4 of 12 successfully treated lesions) defined as greater than 50% reduction in the original gain at the PTCA. We have shown that PTCA is technically possible in a series of cardiac transplant recipients. The primary success and recurrence rates are comparable to the use of PTCA in conventional atherosclerotic coronary disease.

Adult↗
PubMed1991

Cytomegalovirus infection in heart-lung transplant recipients: risk factors, clinical associations, and response to treatment.

The risk factors, clinical associations, and response to treatment of cytomegalovirus (CMV) pneumonia and infection were studied in 65 recipients of heart-lung transplantation. There were 29 episodes of CMV pneumonia in 22 patients. In 80% (20/25) of episodes of CMV pneumonia treated with intravenous ganciclovir, the histologic changes resolved and the patient survived. Among seronegative recipients, a seropositive donor was a significant risk factor for CMV pneumonia and infection in the first 90 days after heart-lung transplantation (P = .004 and .002, respectively). Among seropositive recipients, there was no additional risk associated with a sero-positive donor. Rates of CMV pneumonia and infection were significantly increased when treatment with augmented immunosuppression had been given in the preceding 30 days (P less than .001). A significant association was found between CMV pneumonia or infection and pulmonary bacterial infections occurring 30 days before or after such an episode (P less than .001).

Adolescent↗
PubMed1991

Risk factors for obliterative bronchiolitis in heart-lung transplant recipients.

Obliterative bronchiolitis is the major cause of death of long-term survivors of heart-lung transplantation. Of our first 75 patients who have received heart-lung transplantation, 38 have been followed for a year or longer. Eight patients developed clinical evidence of obliterative bronchiolitis within 15 months of transplantation, of whom four died with postmortem confirmation of extensive obliterative bronchiolitis, interstitial and pleural fibrosis, and vascular sclerosis in the heart and lungs. One further patient died before one year after chronic rejection. All nine patients had evidence on transbronchial biopsy of submucosal fibrosis and vascular sclerosis. Twelve of our remaining patients have shown similar areas of lung fibrosis on transbronchial biopsy, and the other eighteen are well and without fibrosis on transbronchial biopsy. Studies of the 274 biopsies obtained from 38 patients confirmed rejection on 182 occasions with more frequent, more persistent, and more severe rejection in the chronic rejection group than in the without-fibrosis or lung fibrosis groups. Opportunistic infection resulted in pneumonia on 19 occasions, and were most commonly found in lung fibrosis patients. We conclude that obliterative bronchiolitis is the likely outcome in patients with early, poorly controlled, severe rejection.

Adult↗
PubMed1991

Risk factor analysis for the major hazards following heart transplantation--rejection, infection, and coronary occlusive disease.

This study demonstrates the importance of analyzing survival by cause of death in order to achieve a better understanding of the prognostic indicators involved. It further emphasizes the need for analysis of risk factors in both univariate and multivariate models, and the danger of making judgements based on premature analysis of data on follow-up after heart transplantation. Survival following transplantation is characterized by the major hazards of early death due to infection and rejection and late graft loss due to coronary occlusive disease (COD). This study summarizes the first-graft survival experience for 323 transplant patients at Papworth Hospital, and assesses a number of potential risk factors for (1) early mortality, (2) late mortality from COD, and (3) development of COD. The potential risk factors considered for all hazards are donor and recipient age, sex, blood group, and matching of these factors; donor cause of death and recipient immunosuppression; inotropic support; waiting time; preoperative diagnosis and previous cardiac surgery; ischemic time; and extubation time. In addition, for development of, and graft loss from, COD, perioperative rejection and cytomegalovirus infection; hypertension at discharge; and cholesterol, triglycerides, and lipids at two years were assessed as risk factors. Advances in immunosuppression were observed to have increased overall survival rates and decreased mortality from infection, rejection, and COD, as well as decreasing morbidity from COD. Fatal rejection was found to be more likely in female recipients, recipients over 40 years, recipients of grafts from donors over 30 years old, patients who were transplanted for valvular heart disease, and patients who waited less than three months for their transplant. Male recipients of female donor organs were more likely to lose their grafts as a result of COD. Patients older than 50 and hearts from donors older than 40 conferred a high risk of development of and loss from COD. Patients transplanted for ischemic heart disease were more likely to develop COD. High cholesterol, low HDL, high LDL, and high triglycerides at two years after transplant showed some evidence of high risk for the subsequent development of COD, although these relationships are not statistically significant at this stage. Contrary to other recent studies, cytomegalovirus infection was not found to be a risk factor for the development of COD.

Adolescent↗
PubMed1991

Infection and reactivation with cytomegalovirus strains in lung transplant recipients.

Cytomegalovirus pneumonia is a major cause of morbidity and death following lung transplantation (LT) (1). The case fatality rate is highest in the CMV-seronegative recipients (R-) of organs from seropositive donors (D+), which suggests that transmission of CMV may occur with the graft (1), but in seropositive recipients (R+) the comparative importance of reactivation of endogenous virus and reinfection with donor virus is poorly understood.

Cytomegalovirus↗
PubMed1991

Diagnosis of early cardiac transplant rejection by fall in evoked T wave amplitude measured using an externalized QT driven rate responsive pacemaker.

Reliable diagnosis of cardiac allograft rejection is at present only possible using endomyocardial biopsy. We have serially measured epicardial evoked T wave amplitude during ventricular pacing with an externalized QT driven rate responsive pacemaker telemetered to a TP2 analyzer in 13 patients (12 males) followed for 19 (14-26) days after transplantation. A total of 228 records were analyzed. Rejection was defined on endomyocardial biopsy. On 17 of the 31 occasions on which biopsy was performed during the study, specimens showed significant (moderate) rejection. In 11 patients the initial biopsy proven rejection episode was associated with a significant fall in the evoked T wave amplitude from 1.3 (0.7-2.3) mV to 0.6 (0.5-1.8) mV (P less than 0.005), which began 2 (1-4) days earlier. One patient with uncontrolled diabetes mellitus had no change in evoked T wave amplitude during rejection. The evoked T wave amplitude did not fall in the absence of histologic rejection. These results suggest a noninvasive method for detecting cardiac rejection, which appears both sensitive (92%) and specific (100%) in the first rejection episodes.

Adult↗
PubMed1991

Heart-lung transplantation for cystic fibrosis. 1: Assessment.

Forty five patients with cystic fibrosis (age 5-15 years) were assessed for heart-lung transplantation between September 1987 and March 1990. The two main conditions for acceptance were (i) life expectancy less than 2 years and (ii) a severely impaired quality of life. Patients were accepted onto an active waiting list (n = 26), a provisional waiting list (n = 15), or not accepted (n = 4). Selection was made on clinical grounds with objective measurements used as an aid in assessment. As expected, the mean values for objective measures were significantly different between patients on the active waiting list compared with the provisional waiting list/not accepted group for resting heart rate (118/minute v 101/minute), percentage of ideal weight (83.2% v 93.1%), forced expiratory volume at one second as percent of predicted normal (27.3% v 47.6%), Shwachman-Kulczycki score (33.6 v 52.5), Chrispin-Norman x ray score (25.8 v 22.1), 12 minute walk (540 m v 854 m), and minimal oxygen saturation (81.5% v 92%). Psychological evaluation demonstrated a 55% incidence of individual and a 50% incidence of family morbidity. Of the 26 patients accepted onto the active waiting list, 11 have been transplanted (mean waiting time 3.3 months), 10 have died within a mean of 3.7 months of acceptance, and five remain on the active list (mean 5.6 months).

Adolescent↗
PubMed1991

Heart-lung transplantation for cystic fibrosis. 2: Outcome.

From March 1988 to March 1990, 11 children with cystic fibrosis (age 5-15 years) underwent combined heart-lung transplantation at our institutes. Maintenance immunosuppression consisted of cyclosporin and azathioprine with corticosteroids and antithymocyte globulin used perioperatively and during rejection episodes. Six patients (55%) survive from 1.5-23 months all of whom have improved life quality. Actuarial survival to 1 year was 55%. At six months after transplant, mean forced expiratory volume at one second was 73.5% of predicted normal, compared with 25% before transplant. There was one perioperative death, three later deaths associated with obliterative bronchiolitis at two, eight, and nine months, and one from mediastinitis at four months. Of the 15 children accepted for transplantation but not receiving grafts, 10 have died (eight within four months of being placed onto the transplant list). Early postoperative problems included acute reversible rejection (n = 10), meconium ileus equivalent (n = 3), and pancreatitis (n = 1). There was a high incidence of later pulmonary rejection with a mean of 5.7 episodes per patient in the first six months. Pulmonary infection occurred relatively infrequently, with Pseudomonas aeruginosa being the most common pathogen. Persistent diabetes mellitus requiring insulin occurred in four and systemic hypertension developed in one.

Adolescent↗
PubMed1991

Transplantation for end-stage lung disease.

The last decade has seen lung and heart-lung transplantation move from experimental procedures to clinical treatments. Innovative surgical techniques combined with the use of ciclosporin as an immunosuppressive agent have enabled successful transplantation in a wide range of end-stage lung diseases. Exclusion criteria for selecting recipients have relaxed, and improved preservation techniques have facilitated distant donor organ procurement and decreased peri-operative mortality. A range of techniques for the physiological monitoring of the graft as well as diagnosis of major complications such as rejection and opportunistic infection have been introduced. Obliterative bronchiolitis remains a major challenge to the immunologist and to the chest physician in terms of etiology, pathogenesis and treatment. As survival rates improve with improved management, lung and heart-lung transplantations are contributing towards effective treatment of end-stage pulmonary disease as well as providing new insight into pulmonary physiology and into mechanisms of lung disease.

Bronchiolitis Obliterans↗