[The relationship between fatigue and the specific features of a flight shift of civil aviation flight crew].

The paper considers the development of fatigue in civil pilots in relation to the specific features of a flight shift, the duration of a flight, the size of a crew size, and the number of night flight hours. The flight lasting 28 consecutive days negatively affects the pilot's working capacity, with flight hours exceeding 90 hours, due to accumulated fatigue. At the stages "before landing" and "after landing", the degree of fatigue in aircraft commanders depends on the duration of a flight shift, peaking with the flights lasting more than 10-13 working hours. Inclusion of additional crewmen during flight shifts of more than 12 hours results in a reduction in the degree of fatigue in aircraft commanders. Night air departure and arrival are most unfavorable according to the degree of fatigue in aircraft commanders, i.e. the length of night time during flights, they are followed by a night air departure and daylight air arrival; a daylight air departure and night arrival rank third. Flights with daylight departure and daylight arrival are least of all exhausting. A night air arrival is characterized by the greatest degrees of integral fatigue at the stages "before landing" and "after landing", these are little associated with the duration of a flight shift. The existing provision, that such flights may be made thrice in succession, carries a risk for chronic fatigue. It is proposed to permit not more two flight shifts in succession during night air arrival. It is shown that it is necessary to take into account the factor of possible fatigue development on developing the regulation of flight shifts.

[Health state of civil pilots in conditions of intensified piloting load].

Studies of health state of civil pilots working in restrictedly increased piloting hours did not reveal negative influence of increased work loads (90 hours per month and 900 hours per year) on the examinees. In some parameters--medical disqualification due to internal and nervous system disease, transitory disablement morbidity, acute diseases occurrence--reliably positive results were obtained mostly because of increased attention of airline authorities and medical staffers to purposeful prophylactic and rehabilitation work with pilots exposed to intensified piloting load.

[Principal mistakes in expert and diagnostic evaluation of the relationship between noise exposure and ear diseases].

The problem of hearing impairment is considered with special reference to subjects exposed to intense occupational noise. The place of this clinical condition in the overall structure of occupational diseases is discussed with special reference to physical factors of the technological environment responsible for its development. The current untoward situation is underlain not only by imperfections of modern technological processes, inadequate labour protection and industrial hygiene policies, and poor organization of <> manufacturing activities. It is also attributable to the low quality of medicinal-prophylactic examination at the stage of acceptance for employment and the lack of adequate periodic medical monitoring during the subsequent period. This, in turn, is a result of insufficient knowledge of health professionals about methods of prevention, diagnosis, and assessment of occupational loss of hearing. The main mistakes in the analysis of the relationship between the prevalence of ear diseases and the exposure to occupational noise are divided into organizational, diagnostic, expert, and deontological ones. Characteristics of these mistakes and their causes are described.

[Evaluation of the impact of an increased flight duty period on flight safety].

Scientific rationale has been provided for the qualitative indices of the time of flight from the studies of the impact of a gradual (by small values) increase in the time of flight on its safety and the health of airmen. Analysis of the 2003-2004 flight safety trends, by studying the specific changes in a flight crew's working load from the pilot performance quality index and airmen's health status revealed no negative impact of an annual working load increase on the incidence of diseases leading to pilots' medical disqualification. Flight safety indices did not become worse when the flight timeout was increased up to 90 hours during 30 successive hours and 900 hours during a year. Increasing the load of 90 and particularly 100 hours during 30 successive days may present a potential threat to flight safety.

[Noninvasive diagnosis of the main forms of venous hypertension in patients with varicosity]. / Neinvazivnaia diagnostika osnovnykh form venoznoi gipertenzii u bol'nykh varikoznoi bolezn'iu.

The mechanisms of the development of venous hypertension were studied in 212 patients with varicosity. The clinical and instrumental research methods (rheovasography, photoplethysmography, duplex scanning) were employed. Two groups of patients suffering from superficial (simple) and deep (complicated) forms of venous hypertension were distinguished. The superficial form (85.3%) largely occurs under the action of the hydrostatic force of gravitation nature. The axial reflux via the sapheno-femoral and sapheno-popliteal anastomoses, which occurs when the patient is in the vertical position produces insufficiency of the superficial venous valves. The musculovenous pump maintains its function. That is why the hydrody-namic effects via the insufficient perforating veins play a less important part in the development of venous stasis. Trophic disorders emerge 20-30 years after the disease onset and are associated with the development of fairly intensive blood refluxes in the superficial and perforating veins. Dysfunction of the musculovenous pump of the lower extremities underlies the formation of deep hypertension (14.7%). Primary valvular insufficiency of the deep veins induces the formation of hemo-dynamically significant refluxes in the deep, superficial and perforating veins. The work of the musculovenous pump is far from promoting venous return. On the contrary, the movement is associated with an increase in blood volume in all elements of the pump. At first this leads to phlebostasis and then to capillary stasis, provoking the development of trophic disorders at the early stages of disease.

[Oncologic diseases incidence in flying and ground maintenance personnel]. / Onkologicheskaia zabolevaemost' letnogo sostava i nazemnogo aviatekhnicheskogo personala.

Incidence of oncologic disease and oncologic death rate among the flying and ground maintenance personnel in the period from 1996 to 2000 were reviewed. Death rate was found to be below the expectation in both categories. The standard risk for the flying and maintenance personnel made up 0.68 and 0.61, respectively. The flying personnel had a higher risk of cancer of the rectum, large intestine, and prostate. The authors propose to validate USI or analysis for the specific prostate antigen as screening methods of early prostate cancer diagnostics as part of the flyer's medical certification.

[The pathogenesis and surgical treatment of trophic ulcers of the lower extremities against a background of varicose veins]. / Patogenez i khirurgicheskoe lechenie pri troficheskikh iazvakh nizhnikh konechnostei na pochve varikoznoi bolezni.

The state of the musculo-venous pump of lower extremities was studied in 72 patients with trophic ulcers caused by varicose disease. The methods used were: phlebotonometry, phleboplethysmography, US dopplerography, distal ascending and retrograde-femoral, popliteal and talocrural phlebography. It was established that ectasia and/or valve incompetence of deep and muscle veins of the lower extremities with the formation of blood refluxes along the profound, communicating and superficial veins underlie the disturbances of venous hemodynamics. The authors propose a scheme of pathogenesis of the varicose disease trophic ulcers and recommend to perform pathogenetically justified operations.

[Prognosis of complications in cardiovascular diseases in flight personnel]. / Prognozirovanie oslozhnenii serdechno-sosudistykh zabolevanii u letnogo sostava.

The flying personnel of different age groups, including those who continued their professional activity and those who were grounded because of cardiovascular diseases, were followed up for a long period of time. The prognosis value, sensitivity, specificity of various risk factors, symptoms and syndromes of cardiovascular diseases were investigated. Using mathematical prediction methods (Wald's sequential nonhomogeneous statistical test), a diagnostic table for predicting outcomes of cardiovascular diseases for the immediate 5 years was developed. The table was checked and tested on a control sample. The trial showed that the table provided a better accuracy of prediction than the traditional methods normally used in the expertise practice.