BACKGROUND: Altitude illness is a relevant threat to the life and health of participants in mountaineering expeditions. AIM: To determine if impedance cardiography (ICG) can be used in noninvasive monitoring of haemodynamic disturbances at high altitude. METHODS: The study was performed in a group of 13 participants of two mountaineering expeditions in the Himalayas. The ICG examination was performed before the expedition and again at high altitude (4,300-5,700 m) with concurrent estimates of clinical symptoms of acute mountain sickness (AMS) and those suggesting an increased risk of high altitude pulmonary oedema (HAPO). RESULTS: High altitude influenced the haemodynamic profile of the subjects. Significant changes were observed for: stroke index (baseline vs. high altitude: 51.2 ± 10.3 vs. 35.5 ± 11.3 mL/m(2); p = 0.0007), cardiac index (3.24 ± 0.49 vs. 2.63 ± 0.66 L/min/m(2); p = 0.013), Heather index (16.6 ± 4.3 vs. 12.8 ± 4.45 Ohm/s(2); p = 0.006), heart rate (64.1 ± 11.7 vs. 75.4 ± 15.4 1/min; p = 0.045) and systemic vascular resistance index (2,051.3 ± 438.9 vs. 2,668.4 ± 856.2 dyn × s × cm(-5) × m(2); p = 0.027). AMS was observed in six subjects (mild: n = 5, severe: n = 1). Three of them revealed symptoms suggesting an increased risk of HAPO and this subgroup (vs. subgroup without such symptoms) was characterised by higher thoracic fluid content index (baseline: 19.2 ± 0.9 vs. 17.9 ± 2.0 1/kOhm x m(2); p = 0.176, at high altitude: 20.8 ± 1.4 vs. 17.7 ± 1.6 1/kOhm x m(2); p = 0.018) and lower Heather index (baseline: 11.4 ± 2.0 vs. 18.2 ± 3.5 Ohm/s(2); p = 0.028, at high altitude: 9.2 ± 2.1 vs. 13.9 ± 4.4 Ohm/s2; p = 0.028). CONCLUSIONS: ICG may be a helpful, noninvasive tool in monitoring cardiovascular dysfunction occurring at high altitude, especially with breathing disorders.
BACKGROUND: Altitude illness is a relevant threat to the life and health of participants in mountaineering expeditions. AIM: To determine if impedance cardiography (ICG) can be used in noninvasive monitoring of haemodynamic disturbances at high altitude. METHODS: The study was performed in a group of 13 participants of two mountaineering expeditions in the Himalayas. The ICG examination was performed before the expedition and again at high altitude (4,300-5,700 m) with concurrent estimates of clinical symptoms of acute mountain sickness (AMS) and those suggesting an increased risk of high altitude pulmonary oedema (HAPO). RESULTS: High altitude influenced the haemodynamic profile of the subjects. Significant changes were observed for: stroke index (baseline vs. high altitude: 51.2 ± 10.3 vs. 35.5 ± 11.3 mL/m(2); p = 0.0007), cardiac index (3.24 ± 0.49 vs. 2.63 ± 0.66 L/min/m(2); p = 0.013), Heather index (16.6 ± 4.3 vs. 12.8 ± 4.45 Ohm/s(2); p = 0.006), heart rate (64.1 ± 11.7 vs. 75.4 ± 15.4 1/min; p = 0.045) and systemic vascular resistance index (2,051.3 ± 438.9 vs. 2,668.4 ± 856.2 dyn × s × cm(-5) × m(2); p = 0.027). AMS was observed in six subjects (mild: n = 5, severe: n = 1). Three of them revealed symptoms suggesting an increased risk of HAPO and this subgroup (vs. subgroup without such symptoms) was characterised by higher thoracic fluid content index (baseline: 19.2 ± 0.9 vs. 17.9 ± 2.0 1/kOhm x m(2); p = 0.176, at high altitude: 20.8 ± 1.4 vs. 17.7 ± 1.6 1/kOhm x m(2); p = 0.018) and lower Heather index (baseline: 11.4 ± 2.0 vs. 18.2 ± 3.5 Ohm/s(2); p = 0.028, at high altitude: 9.2 ± 2.1 vs. 13.9 ± 4.4 Ohm/s2; p = 0.028). CONCLUSIONS: ICG may be a helpful, noninvasive tool in monitoring cardiovascular dysfunction occurring at high altitude, especially with breathing disorders.
Authors: Pawel Zalewski; David Jones; Ieuan Lewis; James Frith; Julia L Newton Journal: Am J Physiol Gastrointest Liver Physiol Date: 2013-07-18 Impact factor: 4.052