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L D Hudson

Publications and source records attributed to L D Hudson.

At least 145 records · Page 8Linked to original sources
PubMed1983

Early prediction of the adult respiratory distress syndrome by a simple scoring method.

Early identification of patients who will develop the adult respiratory distress syndrome (ARDS) is important in prognosis, management, and candidate selection for studies that evaluate both pathophysiology and early therapy. The purpose of this study was to improve the accuracy of early prediction of ARDS by using a simple scoring method that combines the weighted risks from individual risk factors. By a discriminant function analysis of 136 patients with one or more clinical conditions predisposing to risk of ARDS, simple linear equations were derived in which several different risk factors, weighted by coefficients, served as the variables. We developed several equations from which individual "ARDS scores" could be calculated, and we found retrospectively that half the 46 patients who had developed ARDS scored higher than a particular "index score," while about 90% of the patients who never developed ARDS scored less than that index despite the presence of significant risk factors. We then prospectively tested these equations in 87 other patients and found similar results. In summary, a simple clinical scoring system which can be used soon after admission can identify, with reasonable accuracy, individual patients who are almost assured of developing ARDS.

Humans↗
PubMed1983

Variability of arterial blood gas values in stable patients in the ICU.

To establish guidelines for the interpretation of changes in arterial blood gas (ABG) values, we studied 29 clinically stable ICU patients for spontaneous variability in PaO2, PaCO2 and pH. ABGs were sampled six times over a 50-minute period, during which all patients received a fixed FIO2 of 0.5 via endotracheal tube and underwent no therapeutic interventions. Each sample was analyzed in duplicate with careful attention to method of collection and measurement. The range separating the lowest and highest PaO2 varied from 1 to 45 mm Hg (16.2 +/- 10.9 mm Hg [mean +/- SD] ). For PaCO2 this range was from 1 to 8 mm Hg (3.0 +/- 1.9 mm Hg). Coefficient of variation for PaO2 and PaCO2 averaged 5.1 +/- 3.2 percent (mean +/- SD) and 3.0 +/- 1.5 percent respectively. pH varied within 0.03 +/- 0.02 units. Percentage change in PaO2 between sequential intrapatient samples averaged 5.3 +/- 2.8 percent (mean +/- SD) and 7.1 +/- 7.9 percent over ten- and 50-minute intervals, respectively. Various clinical features were analyzed by multiple regression analysis for their relation to PaO2 variation. Only leukocyte count and mean arterial oxygen content were statistically significant associations (p less than 0.05), but together explained less than 35 percent of the variation observed. Because considerable spontaneous variation occurs, even in stable patients, clinicians should base therapeutic decisions on trends in PaO2 values rather than on isolated changes interpreted without appropriate clinical correlation.

Adult↗
PubMed1982

Clinical predictors of the adult respiratory distress syndrome.

One hundred thirty-six patients meeting our criteria for one or more of eight clinical conditions were prospectively observed for the development of the adult respiratory distress syndrome. A high risk population was identified, including those with sepsis syndrome (38 percent), documented aspiration of gastric contents (30 percent), multiple emergency transfusions (24 percent), and pulmonary contusion (17 percent). The risk from multiple major fractures appeared low but contributed to the risk from other factors. The risk associated with just one factor (25 percent) was compounded by the presence of two (42 percent) and three (85 percent) simultaneous factors, and this finding was more predictive of ARDS than the injury severity score or initial arterial oxygenation. Of the ARDS cases, 76 percent occurred in the initial 24 hours after meeting the criteria. ARDS did not occur after 72 hours unless there was late development of sepsis (3 of 136 patients).

Bacterial Infections↗
PubMed1982

Pulmonary responses to smoke inhalation: morphologic changes in rabbits exposed to pine wood smoke.

Inhalation of smoke can adversely affect pulmonary function; however, the lack of detailed knowledge of exposure conditions and the overall complexity of ensuing clinical problems generally preclude an understanding of the specific role played by smoke in human victims. Using controlled exposures of rabbits to white pine wood smoke, an animal model of smoke inhalation has been created. Light and electron microscopic examinations of injured respiratory tissues from these animals have revealed a reproducible, necrotizing tracheobronchial epithelial cell injury. By six hours after injury, the epithelium remains largely intact but is infiltrated by inflammatory cells; by 24 hours its ciliated and secretory lining cells are largely destroyed, the inflammatory reaction is maximal, but basal epithelial cells retain their normal structural appearances; by 72 hours, its surfaces are largely covered by a nonciliated, stratified reparative epithelium, apparently derived from proliferating and migrating basal cells. The acute injury and early reactions to injury resemble lesions observed in the lungs of human smoke-injured victims, and suggest several physiologic consequences that would provide likely explanations for some of the disabilities observed in these victims.

Animals↗
PubMed1982

Steroid therapy following isolated smoke inhalation injury.

Steroids have no positive influence upon pulmonary related morbidity and mortality following combined smoke inhalation and thermal cutaneous injury (3, 4). Steroid administration following isolated smoke inhalation without concomitant thermal cutaneous injury has, however, been shown to have beneficial effects in previous animal studies (1). This potential therapeutic approach to treatment has not been examined in the clinical setting. Recent hotel fires in Las Vegas, Nevada, resulted in a large cohort of individuals with similar smoke exposures without associated injuries. Two of four hospitals in the triage system administered steroids following injury. Patients were divided into two groups, a steroid-treated, and a non-treated group. These groups were compared using multivariate and frequency analyses. There were no detectable differences in sex, signs, symptoms, and previous medical history. There were likewise no differences between groups with respect to oxyhemoglobin saturation, arterial oxygen tension, arterial pH, and pulmonary-related morbidity and mortality. These data suggest that steroid coverage has little beneficial effect upon pulmonary-related morbidity and mortality following isolated smoke inhalation injury.

Adrenal Cortex Hormones↗
PubMed1982

Bronchocentric granulomatosis with eye involvement.

Bronchocentric granulomatosis is a recently defined entity within the "pulmonary angitis and granulomatosis" group of lung diseases. Unlike the other granulomatoses, extrapulmonary disease has not been encountered with bronchocentric granulomatosis. Therefore, we report a case demonstrating apparent association with scleritis, an uncommon eye disorder often accompanying underlying systemic disease. This introduces a potential source of diagnostic confusion with Wegener's granulomatosis, which can resemble bronchocentric granulomatosis clinically and radiographically, and which has a known association with scleritis.

Adult↗
PubMed1982

The role of transbronchial biopsy for the diagnosis of diffuse pneumonias in immunocompromised marrow transplant recipients.

We studied the use of transbronchial biopsy for the diagnosis of diffuse pneumonia in marrow transplant recipients. Transbronchial biopsy results were directly compared with open-lung biopsy results by performing the procedures simultaneously in the same lobe of the lung and processing the specimens in parallel. There were 24 cases of pneumonia diagnosed in 22 patients. Transbronchial biopsy correctly identified 3 of 5 cases of Pneumocystis carinii and none of the 5 cases of viral pneumonia. The overall sensitivity of transbronchial biopsy was 58%, with a 13% incidence of moderate hemorrhage and no deaths. We conclude that the open-lung biopsy remains the procedure of choice for the diagnosis of acute, diffuse pneumonia in the immunocompromised marrow transplant recipient.

Biopsy↗
PubMed1981

Pityriasis rosea. Viral complement fixation studies.

Eleven patients were seen for pityriasis rosea and underwent acute and convalescent viral complement fixation tests for several respiratory viruses and Mycoplasma. Several patients (6/11) gave a history of antecedent upper respiratory illness; however, no significant rise in titer was seen on any of the complement fixation tests.

Adolescent↗
PubMed1981

Ventilation and perfusion alterations after smoke inhalation injury.

Previous studies of human victims of smoke inhalation injury have demonstrated retention of intravenously infused 133xenon2, 6 suggesting either: (1) true intrapulmonary shunting (Qs) secondary to alveolar collapse, flooding, or obliteration, or (2) perfusion of low ventilation/perfusion compartments (low VA/Q) secondary to bronchospasm, bronchial constriction, or partial bronchial occlusion by cellular debris. To differentiate between and quantitate the relative contribution of intrapulmonary shunt versus low VA/Q compartments, multiple inert gas analysis, as described by Wagner et al.,12 was applied to human victims of smoke inhalation. Studies of an animal model of injury were subsequently performed to confirm these observations. These experiments suggest that early alterations of ventilation and perfusion resulted from increased high VA/Q and dead-space ventilation. Late alterations included significantly increased perfusion of low VA/Q compartments and return of high VA/Q ventilation to baseline levels. True intrapulmonary shunting was notably absent. This physiologic sequence may represent early regional pulmonary vasospasm followed by regional bronchial obstruction and gradual alveolar secondary to bronchospasm, bronchial edema, or partial occlusion by cellular debris.

Airway Obstruction↗
PubMed1980

Association of complement activation and elevated plasma-C5a with adult respiratory distress syndrome. Pathophysiological relevance and possible prognostic value.

Clinical and experimental observations suggest that aggregation of polymorphonuclear granulocytes (PMN) in response to activated complement (C) might contribute to the genesis of the adult respiratory distress syndrome (ARDS), aggregating PMN causing pulmonary dysfunction by becoming lodged in the lung as leucoemboli. PMN-aggregating activity can be detected in C-activated plasma and reflects C5a levels. In 61 patients at risk for ARDS a strong and highly significant correlation was found between the presence of PMN-aggregating activity in the plasma and the development of ARDS; this correlation was also significant when patients with sepsis were excluded from analysis. In patients followed prospectively detection of elevated C5a seemed to be a useful predictor of ARDS. Since corticosteroids have been shown to inhibit PMN aggregation both in vitro and in vivo, the evidence for a role for PMN aggregation in the genesis of ARDS supports the use of corticosteroids in this disorder.

Cell Aggregation↗
PubMed1980

Expression of the human argininosuccinate synthetase gene in hamster transferents.

The structural gene for human argininosuccinate synthetase [L-citrulline:L-aspartate ligase (AMP-forming), EC 6.3.4.5] was transferred to argininosuccinate synthetase-deficient Chinese hamster cells via metaphase chromosomes isolated from human lymphoblast line MGL8D1, a constitutive overproducer of argininosuccinate synthetase, and from its repressible parent, MGL8B2. Argininosuccinate synthetase expression was selected for in citrulline-containing medium, and the human origin of the argininosuccinate synthetase expressed by seven transferents was identified by isoelectric focusing. Stable transferents expressing MGL8D1 argininosuccinate synthetase fell into two classes: (i) those whose argininosuccinate synthetase activity was reduced to 10-50% by arginine, similar to the repression of argininosuccinate synthetase synthesis observed in normal human lymphoblasts, and (ii) those that constitutively expressed argininosuccinate synthetase when grown in the presence of arginine or citrulline. Two transferents from the MGL8B2 donor constitutively expressed human arginonosuccinate synthetase. Three hamster revertants were isolated that constitutively expressed hamster argininosuccinate synthetase. Transferents and revertants exhibited growth-dependent changes in argininosuccinate synthetase activity, in contrast to the constant synthetase activity levels in donor lymphoblasts during growth. The isolation of stable transferents that constitutively or repressibly express argininosuccinate synthetase makes possible the analysis of regulatory signals influencing expression of the argininosuccinate synthetase gene.

Animals↗