High performance flying and effects on pulmonary function.

Abstract

Background Flying high performance aircraft subjects the pilot to physical stress beyond the limits of human tolerance. The pilot faces challenges such as G-forces, low pressure environment and hypoxic air. Some research was done in the mid-1900s to explore the effects of flying on the human body. However, most research focused on topics relevant for enhancing the pilot s performance in the working situation in cockpit, less on pathologic effects of flying. Knowing that a lot of the physical stress on the pilot during high performance flying is directly affecting the lungs, the aim of this paper has been to answer the following question: How does high performance flying affect pulmonary function, both in the short and long term? Method I did a systematic search on PubMed and read titles and abstracts of 597 articles, selecting 11 relevant articles for a critical review. Further I did non-systematic searches in the NATO AGARD-library, UpToDate, and reference lists. I also used Ernsting s Aviation Medicine (4th ed., 2006), one of the most renowned textbooks of aviation medicine. Results There is good evidence that increasing G-forces change the ventilation-perfusion equilibrium in the lungs. Breathing 100 % oxygen results in absorption atelectasis. G-forces, 100 % oxygen and G-suits all contribute to acceleration atelectasis and reduced vital capacity (VC). There is also evidence that poisonous gases and ozone present in cockpit may cause inflammation in the airways. The potential pathological effects of Positive Pressure Breathing (PPB) are unknown. As for long term effects only a few studies exist and the results are inconsistent. The research is more than 20 years old – thus it has not taken into account effects of fourth generation fighter planes introduced in the 80s and 90s. In addition these studies lack certain quality requirements that apply to research today. Conclusion High performance flying has immediate effects on lung function, both as a result of the flying itself and by the variety of aids that help the pilot maintain his function in a physically demanding situation. There is a great lack of knowledge about high performance flying and long term pathologic effects on pulmonary function. Further research on the topic is required.

Background Flying high performance aircraft subjects the pilot to physical stress beyond the limits of human tolerance. The pilot faces challenges such as G-forces, low pressure environment and hypoxic air. Some research was done in the mid-1900s to explore the effects of flying on the human body. However, most research focused on topics relevant for enhancing the pilot s performance in the working situation in cockpit, less on pathologic effects of flying. Knowing that a lot of the physical stress on the pilot during high performance flying is directly affecting the lungs, the aim of this paper has been to answer the following question: How does high performance flying affect pulmonary function, both in the short and long term? Method I did a systematic search on PubMed and read titles and abstracts of 597 articles, selecting 11 relevant articles for a critical review. Further I did non-systematic searches in the NATO AGARD-library, UpToDate, and reference lists. I also used Ernsting s Aviation Medicine (4th ed., 2006), one of the most renowned textbooks of aviation medicine. Results There is good evidence that increasing G-forces change the ventilation-perfusion equilibrium in the lungs. Breathing 100 % oxygen results in absorption atelectasis. G-forces, 100 % oxygen and G-suits all contribute to acceleration atelectasis and reduced vital capacity (VC). There is also evidence that poisonous gases and ozone present in cockpit may cause inflammation in the airways. The potential pathological effects of Positive Pressure Breathing (PPB) are unknown. As for long term effects only a few studies exist and the results are inconsistent. The research is more than 20 years old – thus it has not taken into account effects of fourth generation fighter planes introduced in the 80s and 90s. In addition these studies lack certain quality requirements that apply to research today. Conclusion High performance flying has immediate effects on lung function, both as a result of the flying itself and by the variety of aids that help the pilot maintain his function in a physically demanding situation. There is a great lack of knowledge about high performance flying and long term pathologic effects on pulmonary function. Further research on the topic is required.