Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0032285 (pneumonia)
 54,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since Shumway carried out the first successful heart-lung transplant (HLT) in Stanford in 1981, HLT has become a new therapeutic means for patients with end-stage pulmonary disease or arterial hypertension. However, it is still rarely carried out because of a lack of donors and the complexity of the surgery and postoperative course. This review described the criteria for proper donor and recipient selection, as well as the anaesthetic and postoperative management of HLT patients at Marie Lannelongue Hospital. The lack of suitable organ grafts results, at least in part, from improper donor management. Pulmonary oedema by fluid overloading and excessive haemodilution should be carefully prevented. Low doses of catecholamines and vasopressin maintain circulatory stability and convenient organ function. The indications for HLT (primary pulmonary hypertension, Eisenmenger's complex, and end-stage bronchopulmonary disease) are all characterized by severe pulmonary hypertension, hypoxaemia and cardiac failure. Careful anaesthetic induction is required to avoid circulatory collapse. Cardiopulmonary bypass (CPB) should be started early, so that mediastinal dissection may be carried out in satisfactory haemodynamic conditions. After unclamping the aorta, circulatory support with fluid and catecholamine infusion is often required. High inspired oxygen fraction and end-expiratory positive pressure may be required because of reperfusion pulmonary oedema. Blood transfusion is often needed as there are major blood losses due to dissection of the posterior mediastinum during CPB. Postoperative catecholamine administration is prolonged over several days. Negative fluid balance is often necessary to reduce pulmonary oedema. Improvement in surgical technique, early extubation, and late prescription of steroids have reduced the incidence of tracheal complications. Acute renal failure often occurs as a result of prolonged CPB, hypovolaemia, drug nephrotoxicity and sepsis. Bacterial complications (pneumonia, mediastinitis) are the main causes of early death. After the 15th postoperative day, opportunistic infections and allograft rejection are the main complications. Since 1981, major advances in HLT recipient management resulted in improved survival rates (70-80% at 1 year, and 60-70% at 2 years for the best teams). Despite the complexity of management, and the longterm threat of obliterative bronchiolitis, HLT is, at present time, the only possibility for these young patients to recover a normal quality of life.
 ...
PMID:[Anesthesia and intensive care for heart-lung transplantation]. 205 32

The vasodilator effect of acetylcholine on the pulmonary circulation was first described over 30 years ago, however, the mechanism remained unknown until Furchgott described the endothelium-dependent relaxation of certain vasodilators. It was not until 1987 that endothelium-derived relaxant factor (EDRF) was demonstrated to dilate human pulmonary arteries in vitro. Despite this work, the physiologic role of EDRF in the pulmonary circulation is not known. It has been suggested that hypoxia-induced inhibition of EDRF action or release from pulmonary artery endothelial cells may have a role in hypoxic pulmonary vasoconstriction (HPV) but present evidence suggests that loss of EDRF activity is not directly involved in the phenomenon of HPV. It is more likely that EDRF is released from pulmonary artery endothelial cells during hypoxia and this released EDRF then modulates HPV. If EDRF does modulate HPV in vivo then the role of EDRF in the altered HPV found in disease merits attention. It is known that in disease states such as acute lung injury and pneumonia there is loss or attenuation of HPV which inevitably leads to increased V/Q mismatch and hypoxemia. Whether this attenuation of HPV is due to release of an endogenous vasodilator such as EDRF is presently being investigated. Additionally, there is in vitro evidence that loss of EDRF activity may be important in the genesis of pulmonary hypertension such as found in severe cystic fibrosis. During the next decade the role of EDRF in the human pulmonary circulation in both health and disease will undoubtedly be elucidated.
 ...
PMID:Endothelium-derived relaxing factors and the human pulmonary circulation. 211 36

This report evaluates the histopathologic alterations of a series of 17 patients with the CREST syndrome and relates these alterations to clinical and functional abnormalities. Histologic abnormalities were classified into the following four distinct patterns: pulmonary vascular changes, primarily intimal fibroelastosis, associated with and without pulmonary hypertension; a pattern of fibrosis indistinguishable from usual interstitital pneumonia (UIP); small airways disease; and mixtures of these three patterns. Five patients (29%) had clinical and morphologic pulmonary hypertension, while five others showed mild reductions in diffusing capacity, presumably due to vascular compromise. Five patients had UIP-like interstitial fibrosis, with vascular alterations and restrictive lung disease. Only one patient had small airways disease exclusively. Concentric fibrointimal proliferation and occlusion of arterioles was worse in patients with clinical pulmonary hypertension and interstitial fibrosis of the UIP type, and was not always associated with pulmonary fibrosis. Twenty-one percent of patients developed primary lung carcinomas. The CREST syndrome is unique in the spectrum of pulmonary alterations seen in progressive systemic sclerosis for its high incidence of clinical pulmonary hypertension and propensity for the development of pulmonary carcinomas.
 ...
PMID:The pulmonary pathologic manifestations of the CREST syndrome. 218 93

Three variants of hemodynamic reaction to massive thromboembolism of the pulmonary artery are encountered--hyperkinetic, eukinetic, and hypokinetic. Their manifestations are determined by the patient's cardiovascular status at the onset of thromboembolism, the volume of the embolic obstruction, the degree of pulmonary hypertension, and the concomitant cardiopulmonary pathology. Effective treatment leading to marked reduction of pulmonary hypertension is conducive to increase in the proportion of the hyperkinetic type; ineffective thrombolysis, thrombosis of the inferior vena cava antiembolic filter, recurrent thromboembolism, and infarction pneumonia are the causes of diminished right-ventricular systolic function and reduced cardiac index, i. e. the formation of a hypokinetic type.
 ...
PMID:[Hemodynamic changes in pulmonary thromboembolism]. 224 59

Since April 1988 we have used the Hemopump device, a new means of circulatory support, to successfully treat three orthotopic heart transplant recipients with biventricular failure refractory to conventional therapy. The Hemopump device is a 21F catheter-mounted, transvalvular, intraaortic axial flow pump. Power to the pump is percutaneously transmitted from an external electromechanical drive console by a flexible drive cable. We first used the pump in a 61-year-old man in whom severe steroid-resistant rejection developed 28 days after heart transplant, resulting in cardiogenic shock (cardiac index less than 2.0 L/min/m2) despite maximal inotropic support. In the second case a 49-year-old man with no evidence of pulmonary hypertension sustained cardiac arrest 2 hours after heart transplant, necessitating open chest massage and emergency cardiopulmonary bypass. The third patient was a 9-year-old boy in whom rejection developed 5 months after heart transplant, resulting in congestive heart failure that was unresponsive to maximal medical therapy. The device was implanted by way of the femoral artery approach in the first case, the ascending aorta in the second, and the distal abdominal aorta in the third. Duration of support was 46 hours, 65 hours, and 6 days, respectively. Increased blood flow provided by the pump ranged from 2 to 4 L/min. No device-related complications, such as hemolysis, infection, or thromboembolic events, occurred. All patients recovered normal heart function and were weaned from the device. The first patient is well after 12 months. The second patient died of metastatic lymphoma at 2 months, and the third died of Pseudomonas pneumonia after 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Treatment of cardiac allograft failure by use of an intraaortic axial flow pump. 239 37

Radiation pneumonitis is a life-threatening result of therapeutic thoracic irradiation, yet its mechanisms are poorly understood. We studied the effects of unilateral lung irradiation (3,000 rad) in sheep from the immediate response to the later development of radiation pneumonitis. We defined radiation pneumonitis by its diagnostic clinical feature, radiographic infiltration of the irradiated zone with a straight margin corresponding to the radiation port. The immediate response in the few hours after irradiation was characterized by cough, labored respiration, hypoxemia (arterial PO2 decreased 19 Torr), mild pulmonary hypertension (pulmonary arterial pressure increased 20%), and lymphopenia. Hemodynamics and gas exchange returned to normal by day 2 but became abnormal again before or during radiation pneumonitis at 32 +/- 2 days. Respiratory distress, hypoxemia, and pulmonary hypertension recurred during radiation pneumonitis. Bronchoalveolar lavage during radiation pneumonitis contained increased neutrophils (19 +/- 4%, control = 7%), increased protein (0.27 +/- 0.1 g/dl, control = 0.12 +/- 0.03), and severely impaired ability to lower surface tension. Alveolar macrophages from both lungs during unilateral radiation pneumonitis exhibited impaired generation of superoxide after phorbol myristate (only a 30% increase). Normal control alveolar macrophages increased superoxide production after stimulation greater than 400%. We conclude that unilateral lung irradiation in sheep causes a mild immediate response followed by radiation pneumonitis at 1 mo. Unilateral radiation pneumonitis in this model is associated with ipsilateral neutrophilic alveolitis, increased bronchoalveolar lavage protein, and impaired surfactant function, as well as bilateral functional abnormalities of alveolar macrophages.
 ...
PMID:Unilateral radiation pneumonitis in sheep: physiological changes and bronchoalveolar lavage. 254 Jan 44

The main parameters of the cardiohemodynamics, blood gas composition and acid-base balance were studied in 82 patients with uncomplicated influenza and in 124 patients with influenza aggravated by acute pneumonia. The disorders revealed were essentially dependent on the disease gravity and complications. To evaluate quantitatively the relationship between the respiratory and cardiovascular systems, use was made of the correlation ratios for all the pair parameters under study. The pulmonary artery pressure was highly dependent on the level of the diastolic systemic pressure in grave uncomplicated influenza (r = -0.932) and on the heart rate (r = +0.861) in influenza aggravated by pneumonia. These findings enabled the derivation of appropriate regression equations, which are simple and can thus be widely used in practice to measure the pressure in the pulmonary circulation and to correct pulmonary hypertension. The making up of the correlation schemes permitted evaluating the tendencies in the changes of the most important parameters of the cardiohemodynamics and homeostasis and forming a judgement about tension of the compensatory processes in the body during grave influenza and influenza complicated by acute pneumonia.
 ...
PMID:[Correlation coefficients of the basic indicators of cardiohemodynamics, blood gas levels and acid-base status in influenza]. 309 14

Results with mechanical circulatory assistance for the treatment of profound cardiopulmonary failure after conventional heart surgery have been encouraging. Its usefulness after heart transplantation is not known. Since August 1982, eight patients (of 59 transplant patients) have required support 0 to 48 hours (mean, 19.5 hours) after transplantation. The ages of the patients ranged from 7 days to 52 years (mean, 28.4 years). Underlying recipient heart disease was ischemic in three patients, congenital in two, cardiomyopathic in two, and rheumatic in one patient. Preoperative North American Transplant Coordinators Organization (NATCO) classification was status 9 in one patient (on extracorporeal membrane oxygenation [ECMO]), status 1 in five patients, and status 3 in two patients. Reasons for graft failure, although usually multifactorial, were primarily pulmonary hypertension with right ventricular failure in five patients and pneumonia, hyperacute rejection, and fat embolus in one patient each. In three patients, there was a mismatch in graft size (too small in two adults and too large in one neonate). Graft ischemic times ranged from 75 to 229 minutes (mean, 171 minutes). Two patients received mechanical support with an intra-aortic balloon (IAB), three with ECMO, and three with a right ventricular assist device (RVAD). One of the patients on ECMO and two of the patients with an RVAD also had IABs. Duration of support ranged from 4 hours to 8 days (mean, 3.2 days). Initial hemodynamic stability was achieved in all patients. Complications were common, including sepsis in seven patients and kidney failure in five patients. Only three patients were weaned. One patient with pulmonary hypertension, who was treated with ECMO, died 36 hours after being weaned.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Mechanical circulatory assistance after heart transplantation. 330 17

Pulmonary microvascular occlusive disease has been investigated using balloon occlusive pulmonary angiography in 31 patients with severe adult respiratory distress syndrome (ARDS) of different origins (14 patients with pneumonia, nine with multiple injury, eight with sepsis). Multiple pulmonary artery filling defects (PAFD) were detected in 13 (42%) patients, with a seven (78%) in nine incidence among those with posttraumatic ARDS. The presence of PAFD did not correlate with the severity of the respiratory failure, with the pulmonary hemodynamic alterations (pulmonary hypertension and increased vascular resistance), or with the final outcome (mortality rate was 54% among patients with PAFD and 61% among those with normal angiograms). These findings suggest that widespread pulmonary microthrombosis is a common event in patients with polytrauma and respiratory failure, with an important pathophysiologic role in the onset of posttraumatic ARDS.
 ...
PMID:Pulmonary microthrombosis in severe adult respiratory distress syndrome. 334 22

Using a large animal model of radiation lung injury--the sheep exposed to bilateral thoracic irradiation--we have recently shown the development of sustained pulmonary hypertension during the first 4 weeks following radiation. This is the period prior to the onset of pneumonitis and pulmonary fibrosis. In the present study, we have examined biopsy and autopsy lung tissue from these same sheep and assessed the sequential changes in lung morphology. Six unanesthetized sheep received bilateral thoracic irradiation (a total of 15 Gy); control sheep were sham irradiated. Lung biopsy tissue was taken prior to and at weekly or biweekly intervals during the 4 weeks immediately following radiation. The lungs were also removed at autopsy for light and electron microscopic examination. Our results show early (Week 1) interstitial and progressive intraalveolar edema accompanied by endothelial and epithelial injury. A gradual increase in number of interstitial mononuclear cells was evident from Week 1, both in the lung tissue and in perivascular cuffs. The number of peripheral lung interstitial mononuclear cells was twice baseline from Week 3 and included accumulation of lymphocytes, fibroblasts, and intravascular macrophages. The increased numbers of mononuclear cells paralleled the development of chronic pulmonary hypertension, perhaps suggesting their involvement in the pathogenesis of this disease. Alternatively, it may be that increased mononuclear cell number represents a stage of lung repair.
 ...
PMID:Early structural changes in sheep lung following thoracic irradiation. 335 1


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>