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Biomedical subjects

J M Nelems

Publications and source records attributed to J M Nelems.

At least 19 recordsLinked to original sources
PubMed1985

Carcinoma of the lung in patients under 40 years of age.

Bronchogenic carcinoma in the young population (40 years of age or less) is reported to present in an advanced stage and to have a virulent course. Between 1969 and 1979, 101 patients (65 men and 36 women) presented with cancer of the lung. Their mean age was 36.2 +/- 3.9 years (range 18 to 40 years). Eighty-seven percent had a history of cigarette smoking. Fifty percent of the patients had a strong familial history of malignancy of several organs. The interval between onset of symptoms and diagnosis was 4.01 +/- 3.48 months (3.56 +/- 3.34 for the surgically treated group and 4.16 +/- 3.53 for the nonoperated or unresectable group). Diagnosis was made at bronchoscopy in 32 patients, during thoracotomy in 30 patients, during nodal biopsy in 28 patients, and on cytologic examination of the sputum in 9 patients. The most common cell types were adenocarcinoma in 39 patients, squamous carcinoma in 29 patients, and oat cell carcinoma in 18 patients. Eighty-six patients (the majority) presented in stage III, whereas 9 were in stage I and 6 were in stage II. Twenty-seven patients (26.7 percent) underwent resection for cure, whereas 18 patients were inoperable at surgery. Eighteen of the surgical patients had adjuvant radiotherapy, and chemotherapy, immunotherapy, or both. The average length of survival for the nonresected patients was 7.12 +/- 5.9 months (range 1 to 36 months) and the actuarial survival was 1.5 percent at 36 months. The survival for the surgically managed patients was 56.1 +/- 52.6 months (range 3 to 168 months) or 48 percent at 36 months. At 46 to 168 months after treatment, the only survivors were 13 patients who were surgically managed. Stage III patients had longer survival after surgery (24.1 +/- 24.6 months to 7.09 +/- 5.90 months; range 3 to 74 months and 1 to 36 months, respectively). The survival at 5 years for patients with stage I disease was 78.8 percent, stage II disease 66.6 percent, and stage III disease, 3.6 percent. Early diagnosis and aggressive surgical management are necessary to improve the survival of patients with bronchogenic carcinoma under 40 years of age.

Adolescent↗
PubMed1983

The structure and function of the pulmonary vasculature in mild chronic obstructive pulmonary disease. The effect of oxygen and exercise.

The structure and function of the pulmonary circulation was investigated in 17 patients requiring pulmonary resection. All 17 performed pulmonary function tests and 13 underwent right heart catheterization preoperatively. The surgical specimens of the lung were analyzed with respect to the severity of the emphysema, the severity of the airways disease, and the hypertensive changes in the small pulmonary arteries and arterioles. The data show that pulmonary artery (Ppa) and pulmonary artery wedge (Ppaw) pressures and cardiac output were normal at rest. However, patients with more severe disease showed greater increases in Ppa and Ppaw with exercise than did patients with minimal or no disease. Oxygen breathing had no effect at rest but lowered Ppa and Ppaw during exercise in the patients with more severe disease. Histologic studies showed that greater degrees of emphysema and small airways disease were associated with hypertensive changes in the pulmonary vasculature. We conclude that patients with moderate obstructive lung disease have elevated pulmonary vascular pressures during exercise and structural changes in the pulmonary arteries consistent with pulmonary hypertension when compared with patients with minimal or no disease. Although there are several possible explanations for the increased vascular pressures seen with exercise, we favor gas trapping leading to increased alveolar and pleural pressures, with oxygen breathing preventing this response by shortening the time constants of the peripheral lung units.

Aged↗
PubMed1982

Measurement of regional bronchial arterial blood flow and bronchovascular resistance in dogs.

Little is known about normal variations and control of bronchial blood flow and bronchovascular resistance. We have used the reference-flow technique and 15-microns-diameter microspheres to measure bronchial blood flow under physiological conditions. Dogs (n = 13) were anesthetized and ventilated, and their chests were opened. A ligature was placed loosely around the left main pulmonary artery, and the left atrium was cannulated. In six dogs three sets of microspheres were injected simultaneously into the left atrium, and in another seven dogs the three sets of microspheres were injected sequentially at 0.5-h intervals. Prior to each injection measurements of pulmonary arterial, left atrial, and aortic pressures, cardiac output, and blood gases were made. Five seconds after injection the left main pulmonary artery was transiently occluded to prevent recirculation. After the final injection, dogs were killed, the lungs were removed, and the parenchyma was stripped off the large and small airways of the left lung. Knowing the radioactivity in the trachea, bronchi, parenchyma, and in the reference flow blood and also the aortic and left atrial pressures, we calculated bronchial blood flow (ml X min-1 X g dry lung-1) and bronchovascular resistance (cmH2O X ml-1 X min X 100 g dry lung). Results showed that there were no significant differences between the three measurements of bronchial blood flow when microspheres were injected simultaneously or sequentially. Bronchial blood flow to the left lung was 0.4% of cardiac output; 55% of the total flow went to lung parenchyma and 45% to trachea and bronchi. Expressed as flow/g dry lung the greatest flow was to the airways.

Animals↗
PubMed1982

Exponential analysis of the lung pressure-volume curve as a predictor of pulmonary emphysema.

To compare the predictive value of different pulmonary function tests in the diagnosis of morphologic emphysema, we performed measurements of subdivisions of lung volume, gas exchange, maximal expiratory flow rates, and static deflation pressure-volume curves on 55 subjects prior to surgery for removal of an isolated peripheral pulmonary lesion. Emphysema was graded on the resected lung specimen and the pressure-volume data were fitted to an exponential equation (V = A - Be-KP). By chi-square analysis, K was the best predictor of emphysema in individual subjects and it was the only test that distinguished subjects with moderate emphysema from subjects with mild or without emphysema, but K did not distinguish those with mild emphysema from those without emphysema. As a group those with mild emphysema were distinguishable from predicted normal with K and elastic recoil pressures at 90 and 60% of predicted total lung capacity. We conclude that minimal emphysema may be detected by exponential analysis of the lung pressure-volume curve.

Adult↗
PubMed1981

Tracheo-innominate artery fistula.

Two additional cases of tracheo-innominate artery fistula are presented. One patient survived after prompt surgical management. The emphasis is placed on prevention. However, when post-tracheostomy or post-tracheal resection is complicated by bleeding, the diagnosis of tracheo-innominate artery fistula must be considered. Only appropriate and immediate surgical intervention will save the patient.

Adult↗
PubMed1980

Human lung transplantation.

The 38th attempt at allotransplantation of a human lung is described in a patient with injury due to smoke inhalation. The innovative features in the procedure included prolonged support with an extracorporeal membrane oxygenator during and for four days following transplantation, pharmacologic control of platelet function with sulfinpyrazone, continuous monitoring with a fiberoptic ear oximeter, and pretreatment of the transplanted lung with cytotoxic durgs. The patient survived until the 18th postoperative day, with no evidence of tissue rejection, but he died following ischemic disruption of the bronchial anastomosis. We conclude that the major determinant in the future of human lung transplantation is related to the establishment of a bronchial arterial supply to the transplanted bronchus.

Adolescent↗
PubMed1980

Lung abscess: surgical implications.

The management of lung abscess continues to challenge both physicians and surgeons. The experience at the Toronto General Hospital over a 50-year period (1928 to 1975) has been analysed to define the challenge and to clarify current recommendations for treatment. The 413 patients studied were divided into three sequential chronologic groups that illustrate the initial impact of antibiotic therapy and later appreciation of the pathogenetic importance of aspiration and anaerobic infection. Although cure rates increased dramatically (from 30 to 61%) between 1936 and 1954 with the advent of antibiotics and the decrease in mortality was equally striking (from 47% to 21%), the recent statistics are not as encouraging. In the current period (1962 to 1975), the cure rate with medical treatment has risen from 61% to 73%, and with surgical therapy from 81% to 89%. Unfortunately, the overall mortality has increased from 12% to 25%. The mortality with medical treatment has increased from 10% to 27% but, in contrast, the surgical mortality continues to decrease (14% to 11%). The increased mortality with medical treatment is important. Prolonged antibiotic therapy is frequently necessary, but when resolution is not progressing or when complications ensue, operation must not be delayed.

Adult↗
PubMed1980

Treatment of achalasia: esophagomyotomy with antireflux procedure.

The results of Heller myotomy with Belsey fundoplication in the treatment of 32 patients with achalasia is reviewed. Eighteen who received no previous surgical treatment had good to excellent results. Fourteen patients who had undergone previous Heller myotomy without an antireflux procedure required further surgical treatment. Inadequate myotomy and reflux esophagitis were the causes of failure. In this group four patients who were treated by myotomy, Collis gastroplasty and the Belsey procedure still failed to achieve good to excellent results. The authors conclude that gastroplasty is contraindicated in patients with achalasia.

Adolescent↗
PubMed1978

Extended indications for median sternotomy in patients requiring pulmonary resection.

We have employed median sternotomy in 9 patients for resection of both benign and malignant lung lesions. The most frequent use of this approach was for bilateral wedge resection, though unilateral resection was done in 2 patients. Our experience supports the previously documented usefulness of median sternotomy for minor bilateral resections and suggests that more complex pulmonary resections are possible when an appropriate indication exists. We compared the effects of median sternotomy with those of lateral thoracotomy on postoperative vital capacity and peak airway flow. Both incisions results in a marked loss of measured lung function, but recovery occurs notably sooner after median sternotomy than ater lateral thoracotomy.

Adult↗
PubMed1978

Microbubble elimination during priming improves biocompatibility of membrane oxygenators.

We tested the hypothesis that platelet loss following blood contact with foreign materials is partly related to the presence of microbubbles of gas (gas nuclei) trapped in surface defects on the membrane material. Extracorporeal membrane oxygenator perfusions were conducted in two groups of sheep, with use of standard priming techniques for the oxygenator in one group and a new vacuum priming technique in the other group. The vacuum priming technique was developed to eliminate gas nuclei from the oxygenator surface. With denucleation priming, platelet loss during perfusion was markedly reduced, as was thrombus formation on the membrane surface. The platelet particle-size distribution curve showed a shift consistent with platelet aggregation with the standard priming technique but not with the vacuum priming technique. We conclude that the elimination of trapped gas nuclei from the membrane surface during priming reduces the initial interaction between blood elements and the foreign surface.

Animals↗
PubMed1978

Extracorporeal membrane oxygenator support for human lung transplantation.

Extracorporeal membrane oxygenator (ECMO) support was provided for a 19-year-old boy undergoing right lung transplantation. Perfusion was begun several hours prior to transplant, to correct profound hypercapnia. After the operation, ECMO was required because of inadequate gas exchange by the transplanted lung. Perfusion was continued for a total of 96 hours. During this time, the temporary malfunction of the transplanted lung owing to the reimplantation response reversed, and the patient was successfully removed from the oxygenator and subsequently weaned from the ventilator. He died on the eighteenth postoperative day of bronchial dehiscence. ECMO support appears to be a feasible means of supporting patients during lung transplantation and during the period of reversible lung malfunction that may occur in the early postoperative period.

Adult↗
PubMed1978

Gastroplasty and fundoplication in the management of complex reflux problems.

Between 1963 and 1976, 220 patients with complex reflux problems were managed by combining a modified Collis gastroplasty with a Belsey type of partial fundoplication. All patients had one or more of the following complicating conditions considered indications for the combined operation: peptic stricture (104), esophagitis and shortening without stricture (25), one or more prior hiatal repairs (65), massive herniation (33), and motor disorders associated with reflux (26). Ninety-six percent of the patients were evaluated by personal interview from 1 to 15 years after repair. The operative mortality rate was 0.5 percent. The incidence of significant symptomatic reflux requiring medical therapy was 3 percent and the incidence of troublesome dysphagia was 11 percent. No patient has required further operation for the relief of recurrent symptomatic reflux. Two patients required additional operation for severe residual dysphagia. Twenty patients managed by this repair were evaluated by preoperative, intraoperative, and sequential postoperative esophageal pressure studies. The mean postoperative pressure of 21.4 mm. Hg was more than double the preoperative value. Two publications from other centers reported on similar groups of patients managed by gastroplasty and partial fundoplication, evaluated by preoperative and postoperative esophageal pressures. In these latter publications, the percentage increase in postoperative lower esophageal pressure was significantly less than in our study, and a much higher incidence of symptomatic reflux was recorded. We suggest that the differences in postoperative pressures observed in account for the pronounced differences in the quality of results obtained.

Deglutition Disorders↗
PubMed1977

Surgical treatment for pulmonary emphysema.

Three in-vivo observations stimulated interest in surgical treatment for emphysema: (a) the destructive changes are rarely generalized, (b) the central portions of the lungs are frequently less seriously affected, and (c) marginal folding produces obstructive change in the more normal lung tissue. If destroyed avascular space-occupying areas can be removed, the compressed lung tissue may be stretched to fill pleural space in a functionally effective fashion. Residual elastic tissue will them maintain patency of terminal bronchioles. Preoperatively the extent of the destructive change can be defined most accurately by pulmonary angiography, and zones of functioning capilary circulation can be identified. Forty-seven patients with multifocal space-occupying emphysematous change have been treated surgically. The postoperative mortality was 21% but worthwhile long-term improvement has been obtained in 45% of patients presenting with disabling dyspnea. In these patients, surgical treatment warrants consideration if significant space occupation accompanies the bullous disease, provided alveolar vascularization can be demonstrated in the compressed adjacent normal lung tissue. Limited resections that preserve all vascularized and potentially functioning lung tissue are preferable. It is essential that obliteration of the hemithorax be obtained promptly in view of the high incidence of postoperative complications requiring secondary operative procedures, if 'leaks' and residual spaces are allowed to persist. Postoperative care in a respiratory intensive care unit is mandatory.

Adult↗
PubMed1977

Intraoperative and postoperative esophageal manometric findings with Collis gastroplasty and Belsey hiatal hernia repair for gastroesophageal reflux.

The combination of a Collis gastroplasty with a Belsey Mark IV fundoplication has proved clinically effective in the management of certain patients with complications of gastroesophageal reflux. The present study measured the effect of gastroplasty and Belsey repair on intraluminal pressure changes in the gastroplasty and lower esophagus. Manometric studies were performed preoperatively, intraoperatively, and postoperatively. In each case the gastroplasty segment of the esophagus was found to function as a high pressure zone (HPZ). The pressure in this zone further increased following the fundoplication. It could be diminished with intravenous administration of Buscopan and augmented with intravenously given pentagastrin. The original lower esophageal sphincter in most instances was included in the upper segment of the gastroplasty tube, but the entire length of the gastroplasty tube functioned as an HPZ, and pressures in the tube were considerably higher than those originally present in the lower esophageal sphincter. These studies provide a physiological rationale for the effectiveness of gastroplasty and fundoplication.

Animals↗
PubMed1976

Emergency open lung biopsy.

Twenty-eight patients underwent open lung biopsy on an emergency basis. The clinical course in each case was deteriorating rapidly, and all were in respiratory failure. The correct diagnosis was established in 96% of the biopsies (27 of the 28 patients). The clinical diagnosis prior to biopsy was in error or incomplete in 15 (55%) of the patients. Specific therapy was lifesaving in 12 of the 28 patients. The value of the procedure outweighed the complications. Thrombocytopenia and positive end-expiratory pressure ventilation were not contraindications to biopsy.

Adult↗
PubMed1976

Combination of membrane oxygenator support and pulmonary lavage for acute respiratory failure.

A 24-year-old woman with chronic granulocytic leukemia and alveolar proteinosis required extracorporeal membrane oxygenator support for respiratory failure refractory to conventional therapy. During perfusion, each lung was lavaged with 10 L. of normal saline. The lavage led to marked clearing of the lungs and improvement in pulmonary function. Extracorporeal support was terminated successfully after 54 hours. The patient died 2 weeks later with bone marrow insufficiency and overwhelming sepsis. Pulmonary lavage is technically feasible during venovenous oxygenator bypass, and may be of value, since such lavage debrides alveoli as well as the bronchial tree. Because pulmonary lavage provides a possible means of improving pulmonary function, it seems worthy of consideration as an adjunct to membrane oxygenator support.

Adult↗