Israel Medical Association Journal

Background: Acute respiratory distress syndrome is a well-recognized condition resulting in high permeability pulmonary edema associated with a high morbidity.

Objectives: To examine a 10 year experience of predisposing factors, describe the clinical course, and assess predictors of mortality in children with this syndrome.

Methods: The medical records of all admissions to the pediatric intensive care unit over a 10 year period were evaluated to identify children with ARDS¹. Patients were considered to have ARDS if they met all of the following criteria: acute onset of diffuse bilateral pulmonary infiltrates of non-cardiac origin and severe hypoxemia defined by <200 partial pressure of oxygen during ³6 cm H2O positive end-expiratory pressure for a minimum of 24 hours. The medical records were reviewed for demographic, clinical, and physiologic information including PaO2² /forced expiratory O2, alveolar–arterial O2 difference, and ventilation index.

Results: We identified 39 children with the adult respiratory distress syndrome. Mean age was 7.4 years (range 50 days to 16 years) and the male:female ratio was 24:15. Predisposing insults included sepsis, pneumonias, malignancy, major trauma, shock, aspiration, near drowning, burns, and envenomation. The mortality rate was 61.5%. Predictors of death included the PaO2/FIO2, ventilation index and A-aDO2³ on the second day after diagnosis. Non-survivors had significantly lower PaO2/FIO2 (116±12 vs. 175±8.3, P<0.001), and higher A-aDO2 (368±28.9 vs. 228.0±15.5, P<0.001) and ventilation index (43.3±2.9 vs. 53.1±18.0, P<0.001) than survivors.

Conclusions: Local mortality outcome for ARDS is comparable to those in tertiary referral institutions in the United States and Western Europe. The PaO2/FIO2, A-aDO2 and ventilation index are valuable for predicting outcome in ARDS by the second day of conventional therapy. The development of a local risk profile may allow early application of innovative therapies in this population. 

___________________________________ 

¹ARDS = acute respiratory distress syndrome

² PaO2 = partial pressure of oxygen

³A-aDO2 = alveolar–arterial O2 difference

Background: The growth plate increases its activity in response to exercise. Likewise, decreased physical activity exerts a negative effect on bone growth and development, leading to rarefaction of the subepiphyseal bone. Limb immobilization inhibits the growth plate’s activity, indirectly shown by a recorded arrest in longitudinal growth of the long bones. However, there is no direct evidence concerning the growth plate itself.

Objective: To determine whether the growth plate exhibits measurable microstructural changes in response to decreased levels of physical activity.

Methods: Histomorphometric analysis was used to qualitatively and quantitatively assess the changes in the epiphyseal plate in response to single hind limb immobilization in the rat. In 16 of 25 Sprague-Dawley male rats the left hind limb was immobilized for 3 weeks; the remaining 9 rats served as controls. The left proximal tibia of each animal was examined by computerized image analysis.

Results: There was a decrease in epiphyseal height, cell column density and subepiphyseal trabecular area - all indices of growth plate activity. Metaphyseal cortical thickness was also depressed, thereby confirming the efficacy of the immobilization method applied.

Conclusions: Limb immobilization in the rat induces inhibitory histological changes in the epiphyseal growth plate, which are in contrast to the excitatory microscopic changes seen with exercise. These changes can be assessed quantitatively. Their potential for reversibility remains to be determined by future experiments.

Objectives: To suggest a simple outpatient technique for evaluating the response of arterial oxygen saturation to exercise for use as a marker of disease severity.

Patients and methods: Ninety-six patients with various degrees of COPD¹ were divided into three groups: mild (forced expiratory volume in 1 sec >65%), moderate (FEV1² between 50 and 65%), and severe (FEV1 <50%). Using continuous oximeter recording we measured oxygen saturation during 15 steps of climbing, and quantified  oxygen desaturation by measuring the “desaturation area”, defined as the area under the curve of oxygen saturation from the beginning of exercise through the lowest desaturarion point and until after recovery to the baseline level of oxygen percent saturation. Desaturation was correlated to spirometry, lung gas volumes, blood gas analysis, and 6 min walking distance.

Results A good correlation was found between severity of COPD and baseline SaO2³, lowest SaO2, recovery time, and desaturation area.  A negative correlation was found between desaturation area and FEV1 (r=-0.65), FEV1/forced vital capacity (r=-0.58), residual volume to total lung capacity (r=0.52), and diffusing lung capacity for carbon monoxide (r=-0.52). In stepwise multiple regression analysis only FEV1 correlated significantly to desaturation area.  A good correlation was noted between 6 min walking distance and desaturation area with the 15 steps technique (r=0.56).

Conclusions: In patients with severe COPD, arterial hypoxemia during exercise can be assessed by simple 15 steps oximetry. This method can serve both as a marker for disease severity and to determine the need for oxygen supplementation.

_____________________________________ 

COPD = chronic obstructive pulmonary disease

FEV1 = forced expiratory volume in 1 sec

SaO2 = arterial oxygen saturation

Objectives: To analyze the factors that influence the success of physicians in the ATLS®¹ written tests.

Methods: A retrospective study was conducted of 4,475 physicians participating in the Israeli ATLS® training program between 1990 and 1996. Several variables in the records of these physicians were related to their success or failure in the final written examination of the course.

Results: Age, the region of medical schooling, and the medical specialty were found to significantly influence the successful completion of the ATLS® course.

Conclusions: Physicians younger than 45 years of age or with a surgical specialty are more likely to graduate the ATLS® course. The success rate could be improved if the program’s text and questionnaires were translated into Hebrew. 

¹ATLS® = Advanced Trauma Life Support

Objective: To examine to what extent and for how long nedocromil sodium prevents exercise-induced asthma when given immediately before exertion compared to chronic administration.

Patients and Methods: Eighteen asthmatic patients were given 4 mg NS at 30 min or 3.5 hours before exertion. We compared the resultant effect with that of the same protocol measured after 2 and 4 weeks of continuous treatment with the drug.

Results: Nedocromil sodium decreased exercise-induced asthma similarly at both points when given acutely. Chronic treatment of up to 4 weeks did not improve this protective effect at either interval following the inhalation.

Conclusion: Nedocromil sodium most likely reaches its maximal effect on exercise-induced asthma upon the first administration, although treatment for longer than 4 weeks might be required to prove a chronic effect of the drug.

Objectives: To determine the number of incidents of trauma encountered by medics in the Israel Defense Forces during peacetime, and to ascertain the role of these medics in providing primary trauma care to the victims.

Methods: A retrospective questionnaire, reviewing the activities of medics in treating injured trauma victims, was distributed to medics who were in service for at least 2 years after their professional training.

Results: Of the 128 responding medics, 87 (68%) had actively participated in the treatment of trauma victims under various circumstances. The average number of trauma events was 1.2 events over a period of 2 years per combat medic, and 0.7 for medics stationed in rear units. Their activities included insertion of numerous intravenous fluid lines (57% of medics), assistance in intubations (37%), tube thoracostomies (23%), insertions of central catheters (14%) or orogastric tubes (28%), and manual ventilations (41%).

Conclusion: Since it is difficult to increase the level of practical experience in dealing with trauma within the military framework, new techniques should be applied to improve the trauma training.

Objectives: This article reviews 25 years (1973–98) of experience in bone banking in Israel.

Methods: A nationwide survey on the clinical application of the banked musculoskeletal tissues during 1996 was conducted by means of a written questionnaire sent to all orthopedic departments in Israel.

Results:  The response rate to the questionnaire was 84%. A total of 257 cases were allocated bone allografts: the majority comprised 225 spongy bones, 26 were massive bone allografts and 6 were soft tissue allografts.

Conclusion:  Improvement of quality control and quality assurance of the banked tissues, together with development of skills in the use of osteoinductive and osteoconductive materials, cast the future of musculoskeletal tissue banking.

_________________________________

 * A Tribute to Professor Henry Horoszowski