[Work on a building site at high altitude: physiopathological features and entailments for the occupational medicine]

Introduction. From a physiological perspective the high altitude is defined by altitudes higher than 3000 meters above sea level: at this altitude the atmospheric pressure is reduced to 525 mmHg and the partial pressure of Oxygen drops to 110 mmHg in the ambient air follows and 60 mmHg in the alveolar air. To stay at altitudes above 3000 m s.l.m. therefore places the human organism in front of a notable reduction of the functional respiratory reserve already in conditions of rest, leading to inevitable repercussions on the ability to sustain physical effort. Materials and methods. A population of 39 workers employed in the construction sector at a high altitude construction site (2200-3480 m) was examined. Data relating to sex, age, body mass index, smoking, residence altitude, mountaineering history (maximum altitude reached over a lifetime, frequency of ascents, time spent at high altitude, both for pleasure and for work) and sport practice were collected. Among them, for 25 workers the data of the ergometric tests in normobaric hypoxia (pO2, desaturation and peak values of heart rate, respiratory frequency, ventilation) conducted with simplified mode were collected. Purpose. The study aims to analyze the health of a group of workers exposed to the risk related to staying at high altitude in light of the indications of the scientific literature on health surveillance. Results. The data relating to the group of workers studied with regard to anamnestic data and to the results of ergospirometric examinations in hypoxic conditions are described. Conclusions. In working conditions at high altitude it is necessary to consider both the effect of high altitude in itself, similar to a sort of substantially unchangeable "background risk", and the ways in which high altitude interacts with other risk factors characteristic of the work site activity (which are the same as for any construction site activity that takes place at sea level), considering also the pathophysiological or frankly pathological conditions of which the worker is a carrier. This evaluation can be articulated on two levels: a first level concerning the suitability of the individual for access and the simple prolonged stay in altitude where the work activity will be performed; a second level regarding the suitability of the worker to carry out the work tasks required by the specific task in the particular environmental conditions.