Abstract 356: Sub-clinical and Clinical High Altitude Pulmonary Edema: An Ultrasound Lung Comets Study
Background: The Ultrasound Lung Comets (ULCs) detected by chest sonography are a simple, non invasive, semiquantitative sign of increased extravascular lung water. High altitude pulmonary edema (HAPE) may occur in climbers, with an estimated frequency at 0.2–15%.
Aim: to correlate the occurrence of HAPE with ULCs in a group of recreational climbers
Methods: We evaluated 18 healthy subjects (mean age 45±10 years, 10 males) participating to a high altitude trekking in Nepal. We performed chest and cardiac sonography in all subjects, at sea level and at different altitudes during the ascent. ULCs were evaluated on anterior chest at 28 pre-defined scanning sites.
Results: At individual patient analysis ULCs during ascent appeared in 15/18 subjects (83%) at 3440 height m s.l. and in 18/18 subjects (100%) at 4790 m s.l. in presence of normal left and right ventricular function and pulmonary artery systolic pressure rise (sea level= 24±5 mmHg vs peak ascent= 42±11 mmHg, p<.001). The mean values of ULCs is shown in the figure⇓. An ULCs score showed a negative correlation with O2 saturation (R=−.7; p<.0001).
Conclusions: In recreational climbers, chest sonography reveals a high prevalence of clinically silent pulmonary edema, mirrored by reduction of O2 saturation and increase in pulmonary artery systolic pressure.