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T Higenbottam

Publications and source records attributed to T Higenbottam.

156 records · Page 9Linked to original sources
PubMedDate not supplied

Early graft function after heart-lung transplantation.

Sixty patients underwent heart-lung transplantation at our institution between April 1984 and March 1989. The first five donor organs were removed in an adjacent operating room. Subsequently, organs were removed from distant centers. The method of preservation consisted of cold crystalloid cardioplegic arrest of the heart followed by a cold colloid pulmonary artery flush of a perfusate developed at Papworth Hospital. The lung perfusate is preceded by an infusion of prostacyclin into the pulmonary artery, during preliminary dissection of the donor organs. The total ischemic time ranged from 48 to 51 minutes (mean, 49.6 minutes) for the near-procurement group and from 70 to 249 minutes (mean, 157.6 minutes) for the distant-procurement group. Function of the lungs was assessed by gas exchange, pulmonary function tests, extubation, and survival data. Serial x-ray films were used to monitor graft performance in the postoperative period. We record our clinical experience of early graft function after heart-lung transplantation.

Actuarial Analysis↗
PubMedDate not supplied

Histologic prognostic indicators for the lung allografts of heart-lung transplants.

The histologic changes in transbronchial lung biopsy specimens of heart-lung transplant patients were graded during episodes of acute rejection and when patients were well. Infection was strictly excluded from all episodes studied. Grade of severity of rejection was determined by the magnitude and extent of the inflammatory infiltrate. Biopsy specimens, obtained 1 year after the initial biopsies, were examined for histologic evidence of airway submucosal fibrosis, and each patient's clinical status at this time was recorded. The biopsy material from 22 long-term survivors was studied. On 16 occasions the specimens showed no evidence of rejection (grade 0). Twelve of these sets of specimens were from clinically well patients, and four were from the patients who had clinical evidence of rejection. The other six sets of specimens, from clinically well patients, showed evidence of rejection: three grade 1 and three grade 2. One year later, the clinically well patients had normal biopsy histology without fibrosis and normal lung function. Bronchiolitis obliterans had not developed in any patient. There were 27 episodes of rejection in the 22 patients, of which 23 were confirmed histologically. Eleven sets of specimens had grade 1 acute rejection, eight grade 2, and four grade 3. Three of these patients died, and bronchiolitis obliterans was confirmed at necropsy. Lung fibrosis was more common in specimens taken after 1 year, and lung function was depressed in these patients. The histologic grading of transbronchial lung biopsy material, although still in the early stages of development, provides some predictive value to the long-term outcome of the lung transplant patient, in development of both bronchiolitis obliterans and lesser fibrotic changes.

Biopsy↗
PubMedDate not supplied

Transbronchial biopsy has eliminated the need for endomyocardial biopsy in heart-lung recipients.

Between April 1984 and August 1987, 27 patients have received heart-lung transplantations at Papworth Hospital. In the first 17 patients endomyocardial biopsies were performed routinely in accordance with the practice for heart transplant recipients. It became apparent that in contrast to heart transplant recipients, heart-lung transplant recipients show little evidence of cardiac rejection. As routine endomyocardial biopsies did not contribute therefore to patient management, they were stopped. Conversely, pulmonary rejection was diagnosed either clinically by a decrease in forced expired volume in 1 second (FEV1) in the absence of lung infection or by transbronchial biopsy, which determined when immunosuppression needed to be augmented. The presence of lung rejection was confirmed by resolution of the lung histopathology or improvement in FEV1.

Adult↗
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Histologic changes in heart-lung transplant recipients during rejection episodes and at routine biopsy.

In our experience a lung biopsy specimen taken by means of a fiberoptic bronchoscope is a useful, safe technique for the diagnosis of rejection in heart-lung transplant recipients. To determine that the histologic features associated with rejection can be identified in transbronchial biopsy specimens, 35 biopsy specimens (group A) taken when retrospective review confirmed a clinical diagnosis of rejection without evidence of infection were identified from a total of 107 biopsy specimens. These were compared with 14 biopsy specimens (group B) taken when the patients were well. Several foci of dense perivascular mononuclear cell infiltration with pyroninophilic lymphocytes and plasma cells were seen in 79% of group A biopsy specimens. Fewer foci of non-pyroninophilic cells were seen in group B biopsy specimens (p = 0.005). There was also a difference in the histologic features of the mucosa and interstitial lung tissue. We believe that the early confirmation of rejection followed by adequate augmentation of immunosuppression may prove to be an important factor in reducing the incidence of obliterative bronchiolitis in heart-lung transplant recipients.

Biopsy↗
PubMedDate not supplied

Clearance of inhaled 99mTc DTPA from regions of the lung recently affected by pulmonary embolus.

Pulmonary emboli lead to regional limitation of pulmonary artery perfusion, often without affecting distribution of ventilation. We have studied the effect of this regional reduction of pulmonary artery perfusion on the integrity of epithelium of alveoli (and possibly bronchioli). Integrity of alveolar epithelium was assessed by measuring regional rates of clearance from lung to blood of an inhaled aerosol of a small molecular weight solute, 99mTc DTPA (technetium-99m diethylene-triamine-pentaacetate). Ten patients with pulmonary emboli were studied, where the diagnosis was made from 'mismatching' seen on ventilation (V) and perfusion (Q) lung scintigraphy. Rates of clearance of DTPA in regions with normal V/Q ratios were compared with embolized regions with high V/Q ratios. Clearance rates were increased in embolized regions (V/Q ratio greater than 1): 2.59 +/- (SD) 0.89% X min-1, compared with normal regions (V/Q ratio less than 1): mean 1.39 +/- 0.60% X min-1 (p less than 0.01). In repeat studies in nine patients (one died), after intervals between 2 and 12 weeks, the V/Q ratio of previously embolized regions decreased towards unity in all nine patients, suggesting resolution. The differences in clearance rates for DTPA between normal and embolized regions decreased in association with this return towards normal of V/Q ratios. We surmise that reduction in pulmonary artery perfusion which occurs in pulmonary embolic disease alters the integrity of the alveolar (and possibly bronchiolar) epithelium. This effect is largely reversible, recovering with return of pulmonary artery perfusion.

Aerosols↗
PubMedDate not supplied

Cough induced by changes of ionic composition of airway surface liquid.

Coughing is one of the most common of respiratory systems, and yet few anti-tussives are wholly effective and safe. Centrally acting anti-tussives not only inhibit coughing, but also depress ventilation. As an alternative approach, therapies acting on the afferent limb of the cough reflex are explored. Coughing can be reflexly induced in man by reducing the chloride ion content of airway surface lining liquid (ASL). This can be achieved by inhaling aerosols of hypochloride aqueous solutions nebulized ultrasonically. The cough reflex so provoked may be an important protective mechanism to prevent wide excursions of ionic content of ASL. We have demonstrated that pretreatment with inhaled beta-sympathomimetic and anti-muscarinic drugs inhibit this cough reflex whilst oral beta-sympathomimetics and anti-muscarinics have less effect. It is unlikely that either group of drugs directly affect the vagal epithelial receptors responsible for the cough reflex induced by hypochloride solutions. We hypothesize that these agents may act by limiting the communication between the ASL and the paracellular channels, where the receptors lie between the epithelial cells, by tightening the junctions between cells. This may also explain why beta-sympathomimetic agents inhibit the cough of viral infections and the cough of asthma.

Adrenergic beta-Agonists↗
PubMedDate not supplied

Who waits longest for heart and lung transplantation?

Between August 1982 and December 1992, 260 patients were accepted for heart and lung transplantation, of whom 139 patients underwent transplant surgery. One hundred twenty-one patients have not received transplants, of whom 80 have died, four were transferred to other lists, and 37 were still waiting for suitable organs at the close of the study. Median waiting time for those patients who underwent heart and lung transplantation was 7 months, whereas patients who died waiting spent a median of 5 months on the list. Recipients are matched to donor organs according to blood type, size (total lung capacity), and cytomegalovirus antibody status. These factors, along with age, gender, underlying diagnosis, and Toxoplasma antibody status, were studied to assess their influence on survival after acceptance and time to transplantation. The only characteristic that significantly influenced survival after acceptance was the underlying disease, with patients with Eisenmenger's syndrome having significantly longer survival than the other groups (relative risk = 0.21; p < 0.001). Patients with Eisenmenger's syndrome underwent transplantation at a slower rate than did other patients (relative risk = 0.51; p = 0.012). Patients who had a total lung capacity of more than 6 L underwent transplantation significantly more quickly than did smaller patients (relative risk = 1.98; p = 0.005). Male patients underwent heart and lung transplantation at a quicker rate than did female patients (relative risk = 1.86; p < 0.001), although this was related to size. Patients who had cytomegalovirus-positive antibodies underwent transplantation at almost twice the rate of patients who had cytomegalovirus-negative antibodies (relative risk = 1.92; p < 0.001). Age at acceptance, blood type, and Toxoplasma status did not significantly influence time to heart and lung transplantation. In summary, cytomegalovirus antibody status, patient size, and gender significantly affect the waiting time to heart and lung transplantation. Patients with Eisenmenger's syndrome wait longer than other patients as a result of the natural history of their disease.

Adolescent↗
PubMedDate not supplied

A working formulation for the standardization of nomenclature and for clinical staging of chronic dysfunction in lung allografts. International Society for Heart and Lung Transplantation.

A clinically applicable, standardized method for assessing functional results after lung transplantation is required to evaluate factors that may affect long-term outcome, to permit comparison of results from different centers, and to evaluate results of clinical trials. An ad hoc working group was established under the auspices of the International Society for Heart and Lung Transplantation for the purpose of developing such a clinically applicable system. Chronic allograft dysfunction is often associated with pathologic findings of obliterative bronchiolitis, the cause of which has not been defined. Physiologically, such dysfunction is associated with obstructive airways disease. The group concluded that the forced expiratory volume in 1 second was the most reliable and consistent indicator of graft dysfunction, excluding other identifiable causes. The term bronchiolitis obliterans syndrome was adopted to describe such dysfunction, recognizing that there may or may not be pathologic evidence of bronchiolitis obliterans present. Four stages of bronchiolitis obliterans syndrome were defined, each with two subcategories to indicate whether pathologic evidence of obliterative bronchiolitis had been identified. This working formulation will require reappraisal in the future to reassess its practical application and to make such adjustments as may seem appropriate.

Bronchiolitis Obliterans↗
PubMedDate not supplied

Heart-lung transplantation for end-stage respiratory disease in patients with cystic fibrosis at Papworth Hospital.

Between October 1985 and July 1992 we performed heart-lung transplantation in 42 patients with end-stage respiratory disease caused by cystic fibrosis. Twenty-eight of these patients are alive at 3 months to 7 years after heart-lung transplantation. Actuarial survival at 1 year and 3 years after transplantation was 78% and 65%, respectively, in this group, which compares favorably with 77% and 60%, respectively, in patients without cystic fibrosis undergoing heart-lung transplantation. Similarly no significant difference was found in the incidence of postoperative infections between patients with cystic fibrosis and patients without cystic fibrosis undergoing heart-lung transplantation. Quality of life indexes analyzed by the Nottingham Health Profile reveal significant improvements for patients surviving longer than 3 months from surgery. Long-term survival is determined by the development of obliterative bronchiolitis, which has occurred in 11 patients, six of whom have died. Early postoperative survival appears to be compromised by poor preoperative nutritional status. The study provides evidence that patients with end-stage respiratory disease caused by cystic fibrosis gain a survival advantage and improvement in quality of life after heart-lung transplantation when compared with patients who do not receive this form of therapy.

Actuarial Analysis↗
PubMedDate not supplied

Prognosis of patients with cystic fibrosis awaiting heart and lung transplantation.

Heart-lung transplantation is a successful treatment for patients with cystic fibrosis and chronic respiratory failure. Patients are assessed for surgery when life expectancy is deemed short. This study assesses the ability of measurements of pulmonary function, blood gas levels, and nutritional status to predict survival of patients awaiting heart-lung transplantation and to assess the effect of heart-lung transplantation on survival. Sixty-seven patients with cystic fibrosis were accepted for heart-lung transplantation from 1985 through 1990. Each patient underwent tests of pulmonary function, exercise tolerance, blood-gas levels, and nutritional status. Cox regression was used to analyze the prognostic value of these data. Of the 67 patients accepted for heart-lung transplantation, organs became available for 30; 24 patients died waiting, and 13 patients were on the list December 31, 1990. Eight patients died after transplantation. Patients with above-average forced expiratory volume in 1 second (FEV1) (median, 17% predicted) at assessment were half as likely to die waiting (relative risk, 0.47; 95% confidence interval, 0.23 to 0.97) as patients with below-average FEV1. The relative risk of death for patients on the waiting list was 1.44 (95% confidence interval, 1.17 to 1.77) for each increment in PCO2 of 1 kPa. No effect of nutritional status on waiting list death was found, but seven of eight patients who died after heart-lung transplantation were below 80% predicted weight for height. Using a time-dependent analysis, heart-lung transplantation almost halved the risk of death (relative risk, 0.57; 95% confidence interval, 0.22 to 1.48). Postoperative actuarial survival was 79% (95% confidence interval, 63% to 95%).(ABSTRACT TRUNCATED AT 250 WORDS)

Carbon Dioxide↗