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Biomedical subjects

F A Khan

Publications and source records attributed to F A Khan.

At least 163 records · Page 9Linked to original sources

Oblique hilar tomography, computed tomography, and mediastinoscopy for prethoracotomy staging of bronchogenic carcinoma.

Preoperative oblique hilar tomography was used to evaluate hilar lymph nodes in 150 patients with clinically resectable bronchogenic carcinoma. CT was also used in the evaluation of mediastinal lymph nodes in 50 of these patients. Subsequently, all patients underwent mediastinoscopy and/or thoracotomy. Hilar and mediastinal nodes were evaluated for the presence of metastasis, and these findings were then correlated with the radiographic findings of oblique hilar tomography and CT. CT was found to be a reliable method for prethoracotomy staging of bronchogenic carcinoma and for selecting patients for mediastinoscopy. The sensitivity of CT for evaluation of mediastinal nodal metastasis was 83% and the specificity was 90%. Thus patients with negative mediastinal CT need not undergo mediastinoscopy prior to thoracotomy, while mediastinoscopy and biopsy should be done in patients with enlarged mediastinal nodes on CT. Oblique hilar tomography is an accurate method for evaluation of hilar adenopathy and for predicting mediastinal involvement by extrapolation.

Adult↗

Pulmonary manifestations of the acquired immunodeficiency syndrome (AIDS).

Fifteen patients with AIDS were hospitalized on the pulmonary service during the period from 1981 to 1983. We were impressed with the frequency and severity of lung involvement in these patients and evaluated them with respect to their pulmonary manifestations of AIDS. The 13 men and two women had a mean age of 32 years. Ten were active intravenous drug abusers with a mean drug use of 8.1 years. All presented with profound weight loss, ten with nonproductive cough, and eight with significant dyspnea. Fourteen of 15 patients had Pneumocystis carinii pneumonia (PCP) at the time of our evaluation. Chest radiographs in these 14 patients showed no uniform pattern which was predictive of PCP. However, all 13 patients tested had a widened alveolar arterial oxygen gradient (mean: 59 mm Hg) which correlated well with the presence of PCP. The most common pulmonary finding in our AIDS patients was infection: 14 had PCP which was readily diagnosed by transbronchial lung biopsy in eight patients, and five patients were found to have disseminated Mycobacterium avium-intracellulare which often developed after "recovery" from PCP. Therapy for PCP with trimethoprim/sulfamethoxazole (TMP/SMZ) was unsuccessful in eight of ten patients; four of these eight TMP/SMZ failures responded to pentamidine. Mortality was 100 percent in patients who had AIDS for more than one year, and 70 percent in those less than one year. Despite some symptomatic responses to therapy for pulmonary infections, the mortality in AIDS seems to be unaffected by appropriate therapy for the pulmonary manifestations of this disease.

Acquired Immunodeficiency Syndrome↗

Oblique hilar tomography and mediastinoscopy. A correlative prospective study in 100 patients with bronchogenic carcinoma.

One hundred patients with bronchogenic carcinoma had oblique hilar tomography preoperatively to evaluate the pulmonary hila. Subsequently, all of these patients underwent mediastinoscopy or thoracotomy or both. Hilar and mediastinal nodes were evaluated for the presence of metastasis. These findings were then correlated with the radiographic findings of oblique hilar tomography. We found oblique hilar tomography to be a useful method of selecting patients for mediastinoscopy. The negative predictive value of oblique hilar tomography for mediastinal involvement was 95 percent, while the positive predictive value was 75 percent. Thus, patients with negative findings on oblique hilar tomography need not undergo mediastinoscopic examination prior to thoracotomy.

Adult↗

Tuberculous and posttuberculous bronchopleural fistula. Ten year clinical experience.

Between 1972 and 1982, 15 episodes of tuberculosis-related bronchopleural fistula (BPF) were observed in 13 patients at a municipal hospital in New York City. All 13 had a history of inadequate treatment for pulmonary tuberculosis, and seven had one or more associated chronic debilitating conditions. Past pleural inflammation with resultant fibrothorax appeared to be the source of the late BPF formation in at least seven patients, while rupture of a cavity during active disease was likely in four. Clinical presentation ranged from life-threatening tension-pneumothorax to incidental discovery, a long-term wasting illness being the most common form. Diagnosis was not difficult. Antituberculosis chemotherapy and tube suction were generally employed in treatment, with further surgical drainage procedures done when necessary and possible; open window thoracostomy was usually successful (four of seven BPFs closed, one stable for years), as were one case each of pleuropneumonectomy and decortication. When surgery was not feasible, long-term tube drainage was a useful alternative.

Adult↗

Acquired immune deficiency syndrome. A deadly new disease.

The acquired immune deficiency syndrome (AIDS) represents a new epidemic of major proportions. Risk factors include homosexuality, intravenous drug abuse, Haitian descent, and multiple transfusion in the presence of hemophilia A. The etiology of AIDS remains unknown, but there is increasing evidence implicating a transmissible infectious agent and/or multiple antigenic exposures inducing a loss of immunoregulation. In a high-risk patient, the features of weight loss, generalized lymphadenopathy, and fever should arouse suspicion of AIDS. Diagnostic confirmation includes demonstration of reduced numbers of T lymphocytes with reversal of helper-suppressor T-lymphocyte ratio, presence of unusual opportunistic infections, and a progressive downhill course. The most common infection in AIDS is Pneumocystis carinii pneumonia. Treatment failures with trimethoprim-sulfamethoxazole (Bactrim, Septra) are common; pentamidine isethionate (Lomidine) may be more effective in eradicating the infection. In spite of initial improvement, recurrences of P carinii pneumonia and other opportunistic infections are common. In addition, other protozoan, viral, fungal, and atypical mycobacterial infections are frequent in patients with AIDS. Finally, rare neoplasms such as Kaposi's sarcoma and B-cell lymphoma, including primary lymphoma of the brain, are also being recognized as complications. At present there is no specific therapy for AIDS, and the disease is usually fatal. Continued research will hopefully result in immunomodulation techniques and specific vaccines to combat this serious epidemic.

Acquired Immunodeficiency Syndrome↗

Positive airway pressure in patients receiving intermittent mandatory ventilation at zero rate. The role in weaning in chronic obstructive pulmonary disease.

Over a 20-month period, we treated 180 mechanically ventilated patients in our respiratory intensive care unit. Among these patients, we observed an interesting previously unreported phenomenon in 20 patients with severe chronic obstructive disease. During the weaning from mechanical ventilators of these 20 patients, there was a marked clinical deterioration when the mode of ventilation was changed from intermittent mandatory ventilation (IMV) at zero rate to that of a T-tube setup. To explain this previously unreported observation, we studied and compared nine different intubated patients for possible differences in airway pressure between IMV set up at zero rate and a T tube. We observed that peak airway pressures were greater on IMV at zero rate compared to the peak airway pressures on the T piece in all nine patients. At the end of expiration, seven out of the nine patients had higher airway pressures on IMV at zero rate compared to the T tube. These differences in the peak airway pressures and end-expiratory pressures were statistically significant in both groups. In spite of the obvious limitation of extrapolating the experimental results obtained in one group of patients to explain the clinical observations made in another group of patients, we believe that the higher airway pressures on the IMV system (even without any mechanical ventilation) prevent early collapse of the airways, and this may be of significant importance in successfully weaning patients with COPD.

Humans↗