ECG changes during the experimental human dive HYDRA 10 (71 atm/7,200 kPa).
Undersea Hyperb Med
; 22(1): 51-60, 1995 Mar.
Article
em En
| MEDLINE
| ID: mdl-7742710
ABSTRACT
Electrocardiogram (ECG) analysis was performed in three human divers during a 71 atm (7,200 kPa) saturation dive (COMEX HYDRA 10 experiment). The inhaled gas mixture was slightly hyperoxic; its composition was basically helium and oxygen. Hydrogen was introduced during compression and its partial pressure reached 20 atm. ECG changes were the same in the three divers. Marked bradycardia rapidly appeared at the beginning of compression, then this response adapted throughout the dive. P-R, QRS, and Q-T intervals and the S-T segment did not change significantly. The QRS axis remained stable. However, a rightward shift occurred in P and T vector angles. These changes were correlated with time and gas density, respectively. The modifications of ventricular repolarization during compression are similar to those we observed during the HYDRA 9 COMEX dive. They may correspond to changes in duration of myocardial cell repolarization due to increased intrathoracic pressure changes with dense-gas breathing. A marked global diminution of voltage occurred during the decompression period. This suggests that accumulation of micro bubbles in tissues may influence the impedance, causing an artifact in the amplitude of ECG complexes.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Mergulho
/
Eletrocardiografia
/
Frequência Cardíaca
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
/
Humans
Idioma:
En
Revista:
Undersea Hyperb Med
Assunto da revista:
FISIOLOGIA
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
França