Occupational exposures to radiofrequency fields: results of an Israeli national survey.

Relatively high exposures to radiofrequency (RF) fields can occur in the broadcast, medical, and communications industries, as well in occupations that use RF emitting equipment (e.g. law enforcement). Information on exposure to workers employed in these industries and occupations is limited. We present results of an Israeli National Survey of occupational RF field levels at frequencies between ~100 kHz and 40 GHz, representing Industrial Heating, Communications, Radar, Research, and Medicine. Almost 4300 measurements from 900 sources across 25 occupations were recorded and categorised as 'routine', 'incidental', or 'unintended'. The occupation-specific geometric means (GMs) of the percentage of the American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit values (TLVs) for each of the three exposure scenarios are presented together with the geometric standard deviation (GSD). Additionally, we present estimates of occupation-specific annual personal exposures and collective exposures. The vast majority of the GM of routine exposures ranged from a fraction to less than 1% of ACGIH TLVs, except for Walkie-Talkie (GM 94% of ACGIH), Induction Heating (17%), Plastic Welding (11%), Industrial Heating (6%) and Diathermy (6%). The GM of incidental and unintended exposures exceeded the TLV for one and 14 occupations, respectively. In many cases, the within-occupation GSD was very large, and though the medians remained below TLV, variable fractions of these occupations were projected to exceed the TLV. In rank order, Walkie-Talkie, Plastic Welding, and Induction Heating workers had the highest annual cumulative personal exposure. For cumulative collective exposures within an occupation, Walkie-Talkie dominated with 96.3% of the total, reflecting both large population and high personal exposure. A brief exceedance of the TLV does not automatically translate to hazard as RF exposure limits (issued by various bodies, including ACGIH) include a 10-fold safety factor relative to thermal thresholds and are based on a 6 min averaging period.

Pain scoring--a method for assessing acute antianginal therapy comparison of the response to acute sublingual administration of an isosorbide dinitrate tablet, isosorbide dinitrate spray and nitroglycerin spray in unstable angina.

It is difficult to assess acute therapeutic intervention therapy, particularly in patients with unstable angina. Our aim was to evaluate the feasibility of a pain-scoring method and to compare the response to sublingual administration of an isosorbide dinitrate (ISDN) tablet, ISDN spray or nitroglycerin (NTG) spray. Pain scoring was assessed by the subjective grading of the patients' pain severity from 1 to 10. We studied 205 patients (mean age 66 +/- 13 years). Pain attenuation, defined as at least 50% reduction in pain intensity, occurred in the ISDN tablet, ISDN spray and NTG spray groups after 360 +/- 290, 318 +/- 289 and 233 +/- 271 s, respectively (p = 0.0005). In conclusion, pain scoring is a feasible and useful clinical method to assess antianginal therapy in unstable angina patients. Sublingual nitrate sprays, particularly NTG, seem to alleviate anginal pain faster than ISDN tablets in this patient population.

Randomized controlled trial of late in-hospital angiography and angioplasty versus conservative management after treatment with recombinant tissue-type plasminogen activator in acute myocardial infarction.

Although both the European Cooperative Study Group and the Thrombolysis in Myocardial Infarction IIB trial indicated that angiography and angioplasty as routine measures after thrombolytic treatment do not improve clinical outcome in patients with acute myocardial infarction, the potential benefit of angioplasty may have been negated by the fact that the procedure was performed too soon (less than 32 hours) after admission. A similar study was designed in which delayed invasive treatment was compared with conservative treatment in 201 patients with acute myocardial infarction given recombinant tissue-type plasminogen activator. The 97 patients randomized to the invasive group underwent routine coronary angiography and angioplasty 5 +/- 2 days after thrombolytic therapy, whereas the 104 patients randomized to the conservative group underwent angiography only for recurrent postinfarction angina or exercise-induced ischemia. Baseline characteristics of both groups were similar. In the invasive group, 92 patients underwent angiography, 49 angioplasty and 11 coronary artery bypass surgery. In the conservative group, 40 patients experienced early ischemia, 39 underwent angiography, 20 angioplasty and 4 coronary artery bypass surgery. Reinfarction rate and preservation of left ventricular function at discharge or 8 weeks after discharge did not differ in the 2 groups. Total mortality after a mean follow-up of 10 months was 8 of 97 in the invasive and 4 of 104 in the conservative groups (p = 0.15). However, if only patients who died after the timing of the scheduled protocol catheterization in the invasive arm were included, mortality was 5 of 94 and 0 of 100 in the invasive and conservative treatment groups, respectively (p = 0.02). (ABSTRACT TRUNCATED AT 250 WORDS)

Improved survival but not left ventricular function with early and prehospital treatment with tissue plasminogen activator in acute myocardial infarction.

One hundred ninety patients with acute myocardial infarction (AMI) were treated with recombinant tissue-type plasminogen activator (rt-PA) 2.0 +/- 0.8 hours after the onset of symptoms. Eighty-seven patients were enrolled via mobile intensive care units and 103 through the emergency ward. Patients who were enrolled via the mobile intensive care units were randomized to immediate, prehospital treatment initiation, or to delayed, in-hospital treatment initiation. All 190 patients except 2 underwent delayed coronary angiography and, when indicated, angioplasty at 72 hours after enrollment. Patients treated within 2 hours and those treated 2 to 4 hours after symptom onset had similar preservation of left ventricular function, and similar prevalence of congestive heart failure at discharge. Patients treated within 2 hours of symptom onset had significantly lower short- (0.0 vs 6.3%, p = 0.01) and long-term (1.0 vs 9.5%, p = 0.03) mortality. Prehospital initiation of rt-PA appeared to be safe and feasible and resulted in a 40-minute decrease in the time from symptom onset to treatment initiation.

A new method for simulated mass casualty evaluation : The Beilinson hospital exercise

A new method for evaluating the capabilities and performace of a general hhospital in mass-casualty exercises is described. This method is based on the use of simulation techniques which are realistic relative to the types and availability of the manpower required and tothe time consumed by the assessments, intervention, and administrative duties and demands for each casualty encountered and and the total workload thrust on the hospital by the cumulative requirements of all of the casualties. The simulation can be accoplished only after the time and equipment required for every possible diagnostc, therapeutic and administrative procedure has been assessed for the specific hospital. The simulated victims are selected from a pool of young physicians who are briefed throughly by senior staff physician prior to the exercise. They also serve as controllers in the definition of time mapower consumed for their specific injury set. Given this seting, it is possible to assess the functional performance of a hospital as a unit and for each of its components and also realisticaly estimate its capacity to manage disaster victims using a simulation of a disaster situation with mass casualties (AU)

Quiescent Q fever endocarditis exacerbated by cardiac surgery and corticosteroid therapy.

Q fever endocarditis occurs in up to 11% of patients infected by Coxiella burnetti. Major clues for the diagnosis are culture-negative endocarditis, hepatic involvement, rash, and thrombocytopenia. Characteristically, the diagnosis is delayed. In our patient, Q fever endocarditis occurred without previously recorded signs of infection. Fever, rash, and hepatic involvement all occurred following aortic valve replacement. The histologic picture of the excised valve was consistent with endocarditis, and serologic tests disclosed elevated IgA and IgG antiphase 1 antibody titers against C burnetti, compatible with Q fever endocarditis. It is assumed that the exacerbation of quiescent Q fever endocarditis was caused by cardiac surgery and steroid therapy.