Man in a Hot Climate - Early Studies of the Institute of Military Physiology 

Ezra Sohar, Yair Shapiro, Yoram Epstein

Institute of Military Medicine, Medical Corps, Israel Defense Forces and Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer

In the 1950's many IDF soldiers were hospitalized for heat stroke - about 25% of whom died. Analyzing these cases revealed that commanders misinterpreted human ability to perform in the heat and ignored basic concepts of fluid and electrolyte balance and heat load.

In the early 1960's a series of studies was conducted with regard to soldiers' performance in the heat. The first study (1959), which later became a classic, was conducted during a 21-day march from Eilat to Metula, crossing all climatic zones of Israel. The study was followed by other investigations which approached the issues of voluntary dehydration, fluid consumption vs sweat loss, salt additives, and the effect of heat load on performance.

Based on these early studies, proper regulations were issued to field officers. Over the years, the lessons learned from these studies saved many lives. The number of cases of heat stroke and of other climate-related injuries was dramatically reduced, and performance was enhanced.

Pre-Induction Sport Activity in Prevention of Stress Fractures 

Aharon S. Finestone, Arieh Eldad, Charles Milgrom

Medical Corps, Israel Defense Forces, and Dept. of Orthopedics, Rabin Medical Center, Beilinson Campus, Petah Tikva and Hadassah University Hospital, Ein Kerem, Jerusalem

Pre-induction sports participation of 392 elite infantry recruits was evaluated for correlation with incidence of stress fractures (SF) during 14 weeks of basic training. 23.7% developed lower extremity stress fractures. 72% of the recruits had participated in sports on a regular basis during the 2 years prior to induction. Their fitness as examined by the Bar-Or induction fitness test, was significantly better than that of those who had not trained. 14.9% of the soldiers who had previously participated in ball games (primarily basketball) as an only sport suffered stress fractures, compared to 31.0% of those whose only sport was running (p<0.005).

Training for only 6 months prior to induction had no effect on the incidence of SF. The reason for the difference between ball games and running is probably related to the higher strains and strain rates developed during ball games and to their multidirectional nature, as compared to running.

These findings suggest that participation in a pre-induction program that includes activities that create strains, such as basketball, can reduce incidence of SF in infantry recruits. The training period has to last at least 2 years.

Prediction of Physiological Response from Mathematical Models 

Yoram Epstein, Yuval Heled, Daniel Moran, Yair Shapiro

Institute of Military Medicine, Medical Corps, Israel Defense Forces and Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer

The ability to predict the physiological responses of workers exposed to extreme environmental conditions, has been a challenge to environmental physiologists for more than 3 decades. Therefore, mathematical models have been developed to predict metabolic rate under various levels of work intensity and dynamic changes in body temperature and heart rate.

Based on the effect of exercise on the cardiovascular system, a model was developed to predict mean arterial blood pressure as a function of heart rate. Physiological strain could also be estimated on the basis of thermoregulatory and cardiovascular strains.

This paper summarizes knowledge accumulated during 25 years of studies in the field of mathematical modeling of physiological parameters. Besides analyzing the logic underlying each model, it explains the scientific approach in developing a model from its early concept to the model's application in the field.

Acetaminophen Toxicity in Children - A Therapeutic "Misadventure"

Sarit Shahroor, Yigal Shvil, Mely Ohali, Esther Granot

Dept. of Pediatrics, Hadassah University Hospital and Hebrew University Hadassah Medical School, Jerusalem; and Dept. of Pediatrics, Barzilai Medical Center, Ashkelon

Acetaminophen toxicity after repeated administration of amounts that only moderately exceed recommended doses, is being increasingly reported in alcoholic or fasting adults. Pediatric experience with this pattern of acetaminophen toxicity is sparse.

We present 2 children who developed severe hepatic damage, with renal insufficiency as well in 1, after 15-20 mg/kg of acetaminophen, given at 4-hour intervals for 3-4 days during an intercurrent febrile illness. When given in doses as low as 20 mg/kg at frequent intervals for a number of days, the drug puts children who are vomiting or have sharply reduced caloric intakes at increased risk for severe toxicity.

Increased caution and awareness of the toxic effects of acetaminophen are needed, and it should be dispensed with appropriate package-label warnings.

Acipimox as a Secondary Hypolipidemia in Combined Hypertriglyceridemia and Hyperlipidemia

D. Yeshurun, H. Hamood, N. Morad, J. Naschitz

Hyperlipidemia Clinic, Dept. of Medicine A, Bnai-Zion Medical Center, and Rappaport Faculty of Medicine, Technion, Haifa

32 patients with hypertriglyceridemia, excessive hypertri- glyceridemia, and combined hyperlipidemia, were treated with the nicotinic acid derivative acipimox (Olbetam). First line treatment with bezafibrate, or statins in some with combined hyperlipidemia, had failed. In 10 acipimox was discontinued due to side effects or absence of clinical response. The other 22 completed 6 months of treatment with no side effects.

Acipimox caused a significant 54% decrease in triglyceride levels, a 23% decrease in total cholesterol, and a 12% increase in HDL-cholesterol. LDL-cholesterol was difficult to calculate because of the high triglyceride levels, so no results are presented.

Although acipimox was much better tolerated than nicotinic acid, it also had side effects, but fewer. Acipimox can therefor be used as a second-line drug, mainly in those with combined hyperlipidemia and hypertriglyceridemia.

Laparoscopic Approach in Treating Hepatic Cysts 

P. Schachter, V. Sorin, M. Shimonov, A. Rosen, A. Czerniak

Dept. of Surgery A, Wolfson Medical Center, Holon

Solitary and multiple hepatic cysts are now more commonly found because of advances in imaging techniques. Most hepatic cysts are asymptomatic, but when they do cause symptoms they require surgical intervention. The advent of laparoscopy and of laparoscopic ultrasonography allow comprehensive evaluation and treatment of the cysts.

12 patients with hepatic cysts were treated laparoscopically. 8 with single cysts underwent successful subtotal cyst resection without signs of recurrence (up to 20 years of follow-up). 4 with polycystic liver disease underwent sub-total resection of superficial cysts. Deep cysts were unroofed and drained under laparoscopic ultrasound guidance. In this group, 1 experienced recurrence of symptoms and required partial hepatectomy of the involved segment. In another, a connection between a deep cyst and bile ducts was demonstrated and cystojejunostomy was performed.

The laparoscopic approach in the management of patients with liver cysts is effective and safe, and we recommend it as the procedure of choice for single hepatic cysts. In polycystic liver disease the procedure is much less successful.

Preflight Assessment by Hypoxic Inhalation Test in Cardio-Pulmonary Patients 

J. Lebzelter, G. Fink, E. Kleinman, I. Rosenberg, M.R. Kramer

Pulmonology Institute, Rabin Medical Center, Beilinson Campus, Petah Tikva

Flying may expose passengers to hypoxic conditions, which may induce hypoxemia, particularly in those with chronic heart and/or lung disease. Onset of dyspnea, wheezing, chest pain, cyanosis and right heart failure can lead to urgent need for oxygen during flight. The hypoxia inhalation test (HIT) provides a safe and simple means of identifying those who may develop hypoxemia during flight.

We report our experience with 48 self-reporting patients who underwent HIT prior to pre-planned air travel. They inhaled for 15-minute periods a reduced oxygen concentration (F₁O₂ 15%) under normobaric conditions, during which O₂ saturation was monitored by pulse oximeter; electrocardiogram, blood pressure and symptoms were also monitored. O₂ saturation of 85% (PaO₂ 50 mm Hg) was considered a positive test. In the 8 cases (17%) with a positive test, 5 had chronic obstructive pulmonary disease and 3 had cardiovascular and/or combined heart-lung disease.

We calculated predicted O₂ partial pressure in altitude (PaO₂ ALT) and compared it to actual results in the 8 patients with a positive HIT. In 5, use of the predicted formula would have under-diagnosed the hypoxemia that developed during the HIT. Thus, the results of the HIT changed treatment strategy in these patients. We recommend that patients with positive tests use O₂ (2LPM or 4LPM) during flight.

HIT is practical and of potential benefit in the objective assessment of patients with various degrees of heart, lung or combined heart-lung disease. Clinicians should be aware of the relative risk of hypoxia during flight in such patients, and of the value of HIT in identifying them, leading to increase in its use.

Ethnicity and Emergency Department Visits in the Negev

Shahar Livnat, Eyal Almog, Gad Rabinowitch, Yoram Snir

Dept. of Emergency Medicine, Soroka University Medical Center and Dept. of Industrial Engineering and Management, Ben-Gurion University of the Negev, Beer Sheba

The population of the Negev consists mainly of Jews and Bedouin, who have very different life styles. Patients of both ethnic groups use our emergency department exclusively, providing a unique opportunity to study comparative patient habits.

In gathering and processing the information we used Data Mining technology, which allows search for unique patterns in large data bases. We examined demographic data on some 64,000 emergency department visits during 1997-8, mostly medical and surgical cases, but not trauma cases. Many more were by Bedouin than Jews, and between the ages of 25 and 44, more by women than men. There were changes in trends in comparison with an arrival survey conducted some 11 years before.

Placenta Accreta with Placenta Previa after Previouscesarean Sections 

Eylon Lachman, Alexander Mali, Gabriel Gino, Michael Burstein, Michael Stark

Depts. of Obstetrics and Gynecology and of Pathology, Misgav Ladach Hospital, Jerusalem

The increased rate of cesarean sections in recent decades has brought with it an increase in the frequency of placenta accreta. There are direct correlations between previous cesarean deliveries and also maternal age, with the risk of placenta accreta. There is also a direct correlation between placenta accreta and placenta previa.

The risk of placenta accreta in women who have had placenta previa is 2% for those younger than 35 years and with no history of uterine surgery. The risk increases to 39% for those over 35 who have had 2 or more cesarean sections.

We present 3 cases of placenta accreta admitted in 15 months, all of whom had a history of cesarean sections. The frequency of placenta accreta in our hospital is 1:1,579 deliveries, in line with the 1:1,420 in the literature. We consider hysterectomy the treatment of choice for this serious complication. When performing a cesarean in cases of placenta previa with a history of cesarean sections, the possibility of placenta accreta should be considered.

Etoposide and Cisplatin for Non-Small Cell Lung Cancer 

David B. Geffen, Sofia Man, Yoram Cohen*

Dept. of Oncology, Soroka-University Medical Center and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheba

Etoposide and cisplatin (EP) has been the standard therapy for non-small cell lung cancer (NSCLC) at many cancer centers for over a decade. We analyzed our experience with EP in NSCLC to provide a baseline for comparison with new drugs. From 1986 through 1994, 46 of our patients with NSCLC received EP as first-line chemotherapy. Radiation therapy was administered to 25 of them, including 20 who received it immediately before or concomitantly with chemotherapy. Toxicity was mild and included only 1 episode of neutropenic fever and 1 case of reversible renal failure.

Overall response was 22%. In 3, response was complete (pathologically documented in 2 of them) and in 7 partial. Median survival in locally advanced (stage III) and metastatic disease (stage IV and recurrent) were 12 months and 7 months, respectively. 2 patients are alive and free of disease more than 6 years after diagnosis.

Our results are consistent with other published studies of EP in NSCLC. EP provides modest benefit in locally advanced NSCLC, with minimal toxicity.

Jules E. Harris Chair in Oncology.

Elective Repair of Infra-Renal Aortic Aneurysm 

J.D. Cohen, P. Singer, M. Haddad, A. Zelikovski

Depts. of General Intensive Care and Vascular Surgery, Rabin Medical Center, Beilinson Campus; and Sackler Faculty of Medicine, Tel Aviv University

Age over 80 years is generally considered an independent risk factor in elective surgery for abdominal aortic aneurysm (AAA). As the general population increases in age, more elderly are likely to be candidates for such surgery.

We studied prospectively 100 consecutive patients undergoing elective AAA surgery between 1992-1995. All were operated on by the same team of anesthetists and surgeons and all were transferred to the general ICU for at least the first 24 hours. 16 were above the age of 80 (Group I) and 84 below (Group II).

We recorded preoperative factors (demographics, medical history, risk factor indices, EKG findings, as well as left ventricular ejection fraction (LVEF) and stress imaging when indicated); intraoperative factors (duration of surgery, size of aneurysm, complications and units of blood transfused); postoperative factors (length of ICU stay, duration of ventilation, APACHE II [Acute Physiological and Chronic Health Evaluation] and TISS [Therapeutic Intervention Scoring System] scores; complications in the ICU, need for readmission to the ICU, and mortality).

In Group I LVEF was greater (p=0.03) and aneurysm size significantly larger (p=0.036), but there were no other significant differences between the 2 groups with regard to pre- and intraoperative data. Group I patients were not ventilated as long (p=0.038), but there were no significant differences in outcome factors. Mortality for the whole group was 5% and was not significantly different in the 2 groups (1/16 in Group I and 4/84 in Group II).

We conclude that there is no excess morbidity or mortality in octogenarians undergoing AAA surgery. However risk of the aneurysms rupturing is significantly greater since they are larger. We suggest that age not be considered the sole criterion for aneurysm repair, or at least not in selected patients with normal LVEF.

Laparoscopic Adrenalectomy 

G. Zamir, D. Hazzan, D.J. Gross, S. Lyass, O. Jurim, E. Shiloni, P. Reissman

Depts. of Surgery, Endocrinology and Metabolism, Hadassah University Hospital, Ein-Kerem, Jerusalem

Constant advances and increasing experience in laparoscopic surgery renders it applicable for adrenal surgery. The wide exposure required for open adrenal surgery makes this minimally invasive procedure an attractive and advantageous alternative.

Between 1996-1999, we performed 35 laparoscopic adrenal-ectomies in 30 patients 20-72-years old. Indications included: Conn's syndrome - 14, pheochromocytoma - 11, Cushing's syndrome - 6, nonfunctioning adenoma - 3, and metastatic sarcoma - 1.

5 underwent bilateral laparoscopic adrenalectomy. In 3 (8.5%) the procedures were converted to open operations. Overall morbidity was 13% and there was no mortality. Mean operative time was 188 minutes, but only 130 in our last 10 cases. Mean hospital stay was 4 days and they returned to normal activity an average of 2 weeks later.

According to our study and previous reports, laparoscopic adrenalectomy is feasible and safe and it may soon become the procedure of choice for adrenal tumors.

Glucosamine Sulfate and Chondroitin Sulfates for Degenerative Joint Disease 

R. Debi, D. Robinson, G. Agar, N. Halperin

Orthopedic Dept., Assaf Harofeh Medical Center, Zrifin

Osteoarthritis results from progressive catabolic loss of cartilage proteoglycans due to imbalance between synthesis and degradation. The availability of glucosamine, an intermediate in mucopolysaccharide synthesis, can be rate-limiting for proteoglycan production in cartilage tissue culture.

57 patients suffering from osteoarthritis of the knee were randomized into a group treated for 4 weeks with daily IV glucosamine sulfate (GS) together with 800 mg chondroitin sulfate, and a placebo group. Knee pain at rest, on movement and on palpation, as well as range of knee motion were then recorded.

In the GS group, there was significant reduction of clinical symptoms (p<0.01), but no significant reduction in the placebo group. Physicians' assessment of tenderness and range of motion were significantly in favor of the GS group (p<0.01). In those treated with glycosamine there were no adverse reactions and no changes in laboratory blood tests.

Transient Ischemic ECG Changes in Acute Cholecystitis without History of Ischemic Heart Disease

Lior Lowenstein, Amer Hussein

Dept. of Emergency Medicine, Bnai Zion Medical Center, Bruce Rapport Faculty of Medicine, Haifa

That abdominal distention, nausea, and chest pain may be accompanied by ischemic ECG changes is well known and has been described in the literature. However, very few cases have been reported with acute cholecystitis and ECG changes not due to cardiac ischemia.

We present a previously healthy 20-year-old woman admitted with acute cholecystitis. Prior to surgery routine ECG showed ST-depression and T-wave inversion. The day following cholecystectomy the ECG returned to normal. 1 month later, ergometry and echocardiography were both negative.

Based on the literature and our personal experience, although ECG changes may occur in acute cholecystitis, the possibility of cardiac ischemia must be excluded. However, when no cardiac basis is found, ultrasound of the biliary system might reveal the cause of these ECG changes. Thus, in acute cholecystitis with ischemic ECG changes but no other laboratory or clinical evidence of cardiac ischemia, ECG changes alone are not a contraindication to cholecystectomy. Furthermore, delay in treatment could be harmful.

Relationship Between Preterm Birth and Exertion During Pregnancy

S. Gazit-Nissim, E. Sheiner, M. Mazor, I. Shoham-Vardi

Depts. of Obstetrics and Gynecology, Epidemiology and of Health Services Evaluation, Soroka-University Medical Center, and Ben-Gurion University of the Negev, Beer Sheba

The relationship between physical activity at home and at work during pregnancy and preterm birth was studied. Using a case-control design, 99 women who delivered preterm were compared with 189 women who had term deliveries. The risk of preterm birth was tested in relation to characteristics of work in and outside the home. All women were interviewed post-partum before discharge.

There were no statistically significant differences between the groups in relation to sociodemographic and obstetrical factors, but level of education was significantly lower in the study group versus the control group (p=0.001).

Women who delivered preterm had devoted less time 3 months prior to delivery to household chores (mean of 3.7 hours vs. 4.8 hours in the control group, p=0.002). They also had spent less time walking around the home than the controls (1.2 vs. 1.5 hours, p=0.02). There were no differences between the groups in relation to physical activity outside the home, not during working hours, nor in duration of work. Significantly fewer women who delivered preterm were active in sports (odds ratio 0.22; 95% confidence interval 0.50-0.65; p=0.002).

A low level of education was significantly related to the risk of preterm birth, which may have resulted from lesser compliance with their physician's recommendations. It appears that in women not used to significant physical activity but who had access to adequate prenatal care, physical effort during pregnancy was not related to a higher risk of preterm birth.