Search PubMed⌕ Search

Biomedical subjects

K M Moser

Publications and source records attributed to K M Moser.

At least 145 records · Page 8Linked to original sources
PubMed1982

Patterns of pulmonary perfusion scans in normal subjects.

The prevalence of abnormal pulmonary perfusion (Q) scans in persons without cardiopulmonary disease could condition the usefulness of the Q scan in the evaluation of patients in whom pulmonary embolism is suspected. In a recent study, we found that Q scan defects, particularly lobar or segmental defects, are rarely present in normal young nonsmokers. To determine if normal smokers of the same age group have a higher prevalence of Q defects, we performed 6 view Q scans in 40 subjects 18 to 29 yr of age who had no known active cardiopulmonary disease. Each subject had undergone a history, physical examination, electrocardiogram, spirometry, and posteroanterior chest roentgenogram prior to scanning. All Q scans were interpreted blindly and independently by 2 experienced readers. None of the 40 subjects was found to have an abnormal Q scan defined as the presence of a lobar, segmental, or subsegmental defect on 2 views. When these data were compared with our previous study, statistical analysis found no difference in the prevalence of abnormal Q scans in the 2 groups. We conclude that among young normal persons, abnormal Q scans are extremely uncommon and the prevalence of significant Q defects is not influenced by smoking.

Adolescent↗
PubMed1982

Bronchial hyperreactivity in chronic obstructive bronchitis.

Patients with chronic obstructive bronchitis commonly suffer acute, transient exacerbations, which suggests that episodic bronchoconstriction may play a role in this disease. We studied 22 patients with chronic obstructive bronchitis and no acute improvement in pulmonary function after inhaled sympathomimetics, using methacholine bronchial provocation tests to evaluate the incidence of bronchial hyperreactivity. Patients with clinical or laboratory findings indicative of asthma were excluded. The group demonstrated significant baseline airway obstruction (mean +/- SD forced expiratory volume in one second, 0.96 +/- 0.44) and no improvement after inhalation of isoproterenol (1.68 +/- 8.54% baseline change). All patients were very sensitive to inhaled methacholine, reacting at a dose of 4.29 +/- 5.49 cumulative units. There were no normal responses. These data suggest that airway hyperreactivity may contribute to acute, transient exacerbations experienced by patients with chronic obstructive bronchitis, even in the absence of acute improvement in pulmonary function after the administration of sympathomimetics, and may warrant chronic prophylactic bronchodilator therapy.

Aged↗
PubMed1982

Evidence of lung surfactant abnormality in respiratory failure. Study of bronchoalveolar lavage phospholipids, surface activity, phospholipase activity, and plasma myoinositol.

Autopsy findings suggest that lung surfactant is damaged in the adult respiratory distress syndrome. In the present study 225 bronchoalveolar lavage specimens (78 from 36 patients, 1-78 yr old with respiratory failure, 135 from another 128 patients with other respiratory disease, and 12 from healthy controls) were assayed for the lung profile [lecithin/sphingomyelin (L/S) ratio, saturated lecithin, phosphatidylinositol, and phosphatidylglycerol]. Bronchoalveolar lavage fluid was further analyzed for phospholipids and for phosphatidic acid phosphohydrolase, phospholipase A2, and phosphatidylinositol phosphodiesterase activities. A lipid-protein complex was isolated and analyzed for surface activity, and plasma was measured for myoinositol. There were only small differences seen in the recovery of total phospholipid between respiratory failure patients and normal controls. However, in respiratory failure, phospholipids in bronchoalveolar lavage were qualitatively different from those recovered either from normal controls or from patients with other lung disease: the LO/S ratio, phosphatidylglycerol, and disaturated lecithin were low, whereas sphingomyelin and phosphatidylserine were prominent. These abnormalities were present early in respiratory failure and tended to normalize during recovery. Low L/S ratio (less than 2), and low phosphatidylglycerol (1% or less of glycerophospholipids) in bronchoalveolar lavage was always associated with respiratory failure. Abnormal lavage phospholipids were not due to plasma contamination. The phospholipase studies revealed little evidence of increased catabolism of phospholipids. In respiratory failure, the lipid-protein complexes from lung lavage were not surface active, whereas that from healthy controls had surface properties similar to lung surfactant. Phospholipids from patients with respiratory failure were similar to those from respiratory distress syndrome in the newborn. However, the latter condition is characterized by fast recovery of surfactant deficiency and by high plasma myoinositol that suppresses the synthesis of surfactant phosphatidylglycerol and increases phosphatidylinositol (Pediatr. Res. 1981. 15: 720). On the other hand, in adult respiratory distress syndrome, the abnormality in surfactant phospholipids may last for weeks and in most cases is associated with low phosphatidylinositol, low phosphatidylglycerol, and low plasma myoinositol.

Adult↗
PubMed1982

Longterm follow-up of patients with suspected pulmonary embolism and a normal lung scan. Perfusion scans in embolic suspects.

There is widespread acceptance of the thesis that in a patient with suspected embolism, a normal perfusion lung scan excludes the diagnosis of acute pulmonary embolism. However, limited published data exist which validate this thesis. We have explored this question by longitudinal follow-up of 68 patients who were referred for lung scanning to rule out embolism and proved to have normal perfusion lung scans. Risk factors for venous thromboembolism among these patients were similar to those reported in prior series of patients with pulmonary embolism. Our data support the widely-held views that: 1) a normal perfusion lung scan excludes the diagnosis of clinically significant pulmonary emboli; 2) the diagnostic work-up for suspected pulmonary embolism need not extend beyond a normal perfusion scan; 3) anticoagulant therapy can be discontinued after a normal perfusion scan, except in the presence of documented venous thrombosis; and 4) a normal lung scan has the same value in ruling out embolism in man as does a normal pulmonary angiogram.

Adult↗
PubMed1982

Postpartum pleural effusion: a common radiologic finding.

We did a retrospective study of 112 patients and prospective study of 30 patients and 30 controls to ascertain the incidence of postpartum pleural effusion. An effusion was shown on chest radiographs in 51 patients (46%) in the retrospective study, and 20 patients (67%) in the prospective study. The incidence of pleural effusion in obstetric patients in the prospective study was significantly greater than that of controls (chi-squared test, 20.4, p less than 0.001). There was no difference between patients with effusion and those without in age, race, parity, antepartum complications, method of delivery, fetal outcome, or postpartum complications. We conclude that pleural effusion occurs frequently in the first 24 hours after delivery and that, in the absence of symptoms or signs of cardiopulmonary disorder, no intervention is necessary.

Female↗
PubMed1982

Risk of complications during intravenous heparin therapy.

The records of all patients to whom heparin was dispensed by the pharmacy of the University of California Medical Center, San Diego, during the year 1979 were reviewed. A total of 131 patients above age 15 met the inclusion criteria-they had received more than 10,000 units of heparin per 24 hours for at least 24 hours. All 131 patients were administered heparin by continuous intravenous infusion by peristaltic pump. All heparin was porcine heparin from a single commercial source. The daily mean minimum dose averaged 19,700 units, the maximum, 25,600 units. The activated partial thromboplastin time, usually measured once a day, was the only test used to monitor the dose. Major complicating events occurred in 13 patients (10 percent), and minor complicating events occurred in 10 patients (7.6 percent). All major complicating events occurred in patients with serious concurrent diseases. In subpopulations of 58 patients without concurrent disease, and of 24 in whom heparin was initiated for suspicion of thromboembolism that was not confirmed, no major complicating events occurred. These data indicate that continuous, intravenous administration of heparin is associated with minimal risk, and that risk is concentrated among older patients with serious concurrent disease.

Adult↗
PubMed1982

Pulmonary endarterectomy for chronic thromboembolic obstruction: recent surgical experience.

Pulmonary thromboendarterectomy for chronic pulmonary emboli was performed on ten patients, ages 20 to 67 years, between July 1977 and June 1981. Five patients each were assigned to New York Heart Association functional classes III and IV. All patients had pulmonary hypertension and increased pulmonary vascular resistance. Obstruction beginning in the lobar arteries and involving more than 50% of the sequential arteries was present in all patients. Five patients had complete obstruction of a pulmonary artery. All patients had obstructive disease in both lungs. Pulmonary thromboendarterectomy was performed through central pulmonary arteriotomies and by use of deep hypothermia and circulatory arrest. Circulatory arrest was employed in one to four periods totaling up to 60 minutes. No neurologic deficit was observed. All patients developed reperfusion edema in the lungs. All patients had improvement in pulmonary hypertension and pulmonary vascular resistance. One patient died of lung failure in the late postoperative period. All survivors had improved lung function, with two functional classes in seven patients. Improvement in one equaled three functional classes and in one, by one functional class.

Adult↗
PubMed1981

Deep venous thrombosis and pulmonary embolism. Frequency in a respiratory intensive care unit.

Radiofibrinogen leg scans were performed in 34 patients admitted to a respiratory intensive care unit (ICU) for treatment of acute respiratory failure. In 23 patients, the leg scans were performed during the first ICU week, and abnormal leg scans developed in three (13%). In 11 patients, leg scans were done beyond the first week; all were normal. Autopsy incidence of embolism was 20%. No patient died of embolism. The low frequency of fatal embolism had led us to discontinue the routine use of low-dose heparin prophylaxis in these patients in our respiratory ICU. In its place, we have substituted an ongoing investigation of noninvasive monitoring with both radioactive fibrinogen leg scanning and impedance plethysmography. From such investigations should emerge more definitive strategies for dealing with venous thromboembolism in this complex patient population.

Acute Disease↗
PubMed1981

Identification of pulmonary emboli in the dog: comparison of angioscopy and perfusion scanning.

Fifteen dogs were studied by perfusion scan, angioscopy and autopsy. In 10, emboli were formed in leg veins and released before study; five dogs were not embolized and served as controls. In controls, angioscopy disclosed no emboli, perfusion scans were normal after angioscopy and autopsy disclosed no emboli. Among the embolized dogs, 23 emboli were identified at autopsy. Perfusion scans disclosed 23 defects, but in three dogs there was a disparity between scan and autopsy localization. Angioscopy identified 21 of the 23 autopsy-defined emboli and localized them correctly; two emboli in vessels less than 1 mm in diameter were not visualized. Angioscopy may provide a useful new approach in animal investigations of pulmonary embolism and perhaps, after additional study, in selected patients.

Animals↗
PubMed1981

Flexible fiberoptic bronchoscopy for diagnosing pulmonary coccidioidomycosis.

To assess the diagnostic yield of flexible fiberoptic bronchoscopy (FFB), we reviewed records of 30 patients who had (1) cultural and/or histologic evidence of coccidioidomycosis, (2) abnormal chest roentgenograms, and (3) undergone FFB. Each patient underwent a complete examination including sputum collection for smears and culture. As additional diagnostic information was needed, FFB was performed in all patients, followed by percutaneous needle aspiration in 4 patients and thoracotomy in 10. Prebronchoscopy sputum cultures yielded Coccidioides immitis in 6 of 30 patients (20%). Bronchoscopy provided specimens diagnostic of coccidioidomycosis in 16 of 30 patients (53%), and in 10 of 30 (33%), FFB was the first procedure of the examination to produce a diagnostic specimen. The diagnosis was first obtained by needle aspiration in 1 of 30 (3%), by extrathoracic specimens in 3 of 30 (10%), and by thoracotomy in 10 of 30 (33%). All 8 patients with a solitary pulmonary nodule (SPN) had nondiagnostic FFB and comprised the majority of patients not diagnosed until thoracotomy was performed. When patients with a SPN were excluded, 20 of 29 (69%) FFB procedures documented coccidioidal infection. Seven of 22 (32%) prebronchoscopy sputum collections compared with 17 of 29 (59%) FFB procedures produced positive cultures for C. immitis. One of 22 (5%) prebronchoscopy sputum collections, compared with smears and biopsies from 8 of 29 (28%) FFB procedures, produced immediate microscopic evidence of coccidioidomycosis. Coexisting pulmonary pathologic findings in 4 patients were uncovered by FFB. Except in patients with a SPN, FFB is a valuable procedure for documenting pulmonary coccidioidomycosis when sputum specimens are nondiagnostic.

Biopsy, Needle↗
PubMed1981

Patterns of pulmonary perfusion scans in normal subjects.

A vital factor conditioning the usage of the pulmonary perfusion (Q) scan in the evaluation of patients suspected of pulmonary embolism is the prevalence of abnormal Q scans in subjects free of cardiopulmonary disease. Because this prevalence has not been well defined, we performed Q scans in 80 nonsmoking subjects 18 to 29 yr of age having no known active cardiopulmonary disease. Each subject underwent a history, physical examination, electrocardiogram, spirometry, and PA chest roentgenogram, followed by a 6-view Q scan. Two subjects in whom a Q defect was suspected underwent a 133Xe equilibrium-washout ventilation (V) scan. All Q scans were interpreted blindly and independently by 2 experienced readers. Seventy-nine of the 80 Q scans were read as normal. No subject demonstrated a lobar or segmental defect. One of the 80 subjects, who had a mild pectus excavatum, had a left upper lobe subsegmental defect, which was not seen on the V scan. Based on the statistical analysis of these data, no more than 3.68% of normal nonsmoking persons in this age group may have a lobar or segmental Q scan defect and no more than 6.77% may have a subsegmental defect (with 95% confidence). Therefore, our study indicated that Q scan defects, particularly lobar or segmental, are rarely present among normal nonsmokers in this age group.

Adolescent↗
PubMed1981

Is embolic risk conditioned by location of deep venous thrombosis?

Sixty-eight patients clinically suspected of having (33), or at high risk for (35), deep venous thrombosis were studied with contrast venography, radiofibrinogen leg scanning, and impedance plethysmography as well as ventilation and perfusion lung scans. Thrombosis limited to the veins in the calf of the leg (unilateral or bilateral) was shown by venography in 12 patients. None of these patients had clinical symptoms or scan results indicating embolism. Fifteen patients had thrombosis involving proximal (thigh) as well as distal (calf) veins by venography. Eight had scan evidence of embolism, although only one was symptomatic. The combination of radiofibrinogen and impedance tests allows accurate detection of both the presence and location of deep venous thrombosis. The availability of sensitive and specific, noninvasive methods for detecting and localizing venous thrombosis, as well as the apparently low embolic risk of calf-only thrombosis may condition future approaches to prophylaxis and treatment of patients with or at high risk for deep venous thrombosis.

Humans↗
PubMed1981

Transfer factor therapy for histoplasmosis in a patient with Hodgkin's disease.

A patient with recurrent chronic histoplasmosis was diagnosed also as having Hodgkin's disease. Studies of cell-mediated immunity (CMI) demonstrated no reaction to histoplasmin by skin test, lymphocyte transformation (LT), or leukocyte inhibition factor (LIF) assay. Clinical and immunologic studies were performed during treatment with 19 doses of dialyzable transfer factor (TF) prepared from a normal donor with strong CMI against histoplasmin. Transfer of CMI to the patient was demonstrated by all three tests. All tests reverted to nonreactive during the period of observation. Repeated doses of dialyzable TF were followed by reconversion of skin tests. The LIF assay was most reactive. Reactivation of histoplasmosis occurred during antimetabolic therapy for Hodgkin's disease; however, the lesions cleared rapidly when TF was added to amphotericin B. Amphotericin B was administered at a dosage of 25 mg three times each week during the entire study.

Adult↗
PubMed1980

Right and left ventricular dysfunction in patients with chronic obstructive lung disease. Assessment by first-pass radionuclide angiography.

To evaluate the relationship between right and left ventricular function in patients with obstructive lund disease, we studied 10 normal subjects (group 1) and 37 patients with chronic obstructive pulmonary disease by first pass radionuclide angiography. These 37 patients were divided into three groups: nine with mild chronic obstructive pulmonary disease (group 2), 20 with severe chronic obstructive pulmonary disease (group 3) and eight with severe chronic obstructive pulmonary disease and primary left ventricular disease (group 4). In each subject right ventricular ejection fraction (RVEF), left ventricular ejection fraction (LVEF) and ejection fraction during first third of systole (first third LVEF) were calculated. (For table: see text.) p less than 0.05 versus 1. All subjects in group 2 had normal left ventricular and right ventricular function. In group 3, 11 of 10 (55 per cent) had a low RVEF and three of 20 (15 per cent) a low LVEF. However eight of 20 in this group (40 per cent) had a depressed first-third LVEF. The correlation between decline in RVEF and first-third LVEF was good r = 0.73. We conclude that (1) certain indices of early systolic left ventricular ejection are abnormal in many patients with chronic obstructive pulmonary disease and correlate with the decline in right ventricular function; (2) this is not seen in patients with mild chronic obstructive pulmonary disease and is worse in patients with underlying left-sided heart disease.

Adult↗
PubMed1980

Cardiopulmonary consequences of decompression stress.

Clinically undetectable venous gas emboli (VGE) can be routinely demonstrated in both animals and men undergoing clinically uneventful decompression from hyperbaric environments. The effect of VGE on gas exchange and pulmonary hemodynamics in this setting is unclear. We therefore have studied the cardiopulmonary effects of clinically uneventful decompression on unanesthetized sheep. Sheep were instrumented with a femoral arterial catheter, Swan-Ganz catheter, chronic tracheostomy, and were loosely restrained in the prone position. Following baseline measurements of pulmonary artery pressure (pPA), mean pulmonary artery wedge pressure (pPAw), cardiac output (CO), arterial and mixed venous blood gases, Doppler ultrasonic bubble detection, and V/Q scans using 133Xe, the animals were exposed to: (a) a 15-min exposure to 6.03 ATA (n = 8), (b) a 17.5-min exposure to 6.03 ATA, or (c) a 15-min control period at 1 ATA (n = 7). All measured parameters remained unchanged in the control group. VGE were detected in all animals exposed to pressure. In both exposure groups CO fell 20% (P < 0.05) and pulmonary vascular resistance (PVR) rose 60% (P < 0.05) compared to the control group. This rise in PVR was significantly in excess of that predicted for the observed fall in CO. Analysis of pPA and pPAw suggested neither right nor left ventricular failure. No significant abnormalities of gas exchange were detected. V/Q scans remained unchanged in all animals. We conclude that CO and PVR are altered by clinically uneventful decompression stress.

Animals↗