Suspension Trauma: The “SOSPESI” Project
C.A.M.P. and the University of Milan Bicocca (Department of Health Sciences, Clinical Physiology and Sport Centre) collaborated on the research project “SOSPESI”*, regarding the possibility of the occurrence of syncope in workers who use a harness.
Suspension syndrome may occur in any individual as a result of inert suspension in a harness and is caused by a phenomenon known in human physiology as “orthostatic intolerance”: in a static vertical position, there is an accumulation of blood in the lower limbs, in the pelvis and abdomen with a consequent decrease in venous return to the heart. A reduced venous return results in a decrease in cardiac output and therefore a condition of deficits of cerebral, cardiac and renal oxygenation. Syncope due to this phenomenon can take about 30 minutes (average values, verified in the experimental set of the project SOSPESI, in 40 individuals) and if the person is not rescued within a short time, he/she will die of multivisceral hypoxia.
We also verified, through the NIRS (near infrared spectroscopy) method, that the leg loops of the harness are not responsible for the obstruction of venous return, but it is the orthostatic and inert position that causes the failed return of blood to the heart. However, the comfort of the harness is an important factor in precipitating events triggered in people during a syncopal event.
After having checked that some variables may influence the onset of syncope from inert suspension (time of suspension, environmental temperature, blood pressure) in the first phase of the project, we tried to identify the harness characteristics that can prolong the duration of suspension in working conditions.
Passive suspension tests were carried out on 2 existing harness models (Golden Top Evo Alu and Access) and on a prototype studied in collaboration with the Clinical Physiology and Sport Centre, assessing a number of medical parameters and analysing the comfort perceived by testers.
The choice of harness must then consider comfort in the following areas: inguinal (construction, amplitude, padding), lumbar (possible support), dorsal (construction that does not limit the physiological excursion of the respiratory muscles), latero-cervical (which does not create any compression on the neck where carotid blood vessels run).
The results of this study helped our R&D office to develop the new GT Sit, GT Chest, and GT ANSI harnesses: the construction of the leg loops at inguinal level, the characteristics of the belt and the shape of pectoral padding were designed to dramatically improve the comfort of the worker.
Click HERE to look up the report relative to the first phase of the project
Click HERE to look up the report relative to the second phase of the project
* The other sponsors of the research project are: “Servizi e Sistemi”, “Geoneer Group”.