[Experimental studies of high frequency jet ventilation improved by enhancing expiratory turbulence].
OBJECTIVE
To improve the effect on CO2 elimination during high frequency jet ventilation by enhancing expiratory turbulence.


METHODS
Nine healthy dogs with steam-induced type I respiratory failure were basically applied with high frequency jet ventilation (HFJV), and high frequency two-way jet ventilation (HFTJV), HFJV combined with thoracicoabdominal compression (HFJV+TAC), and HFJV combined with thoracicoabdominal compression-decompression (HFJV+ TACD) randomly for 30 min, respectively. The parameters were determined and the Reynolds numbers (NR) were calculated.


RESULTS
Reynolds numbers were more than 3000 in all patterns, suggesting that the airflow was turbulent. Expiratory Na was higher. The NR of the latter three patterns was more significantly higher than that of HFJV (P < 0.01). CO2 elimination was 126, 111, 137 ml. min-1 in the latter three patterns, respectively and significant (P < 0.05) or very significant (P < 0.01) compared with 98.0 ml.min-1 in HFJV. Corresponding changes occurred in PaCO2. NO significant differences (P > 0.05) were observed in hemodynamic parameters.


CONCLUSIONS
HFJV combined with inverse jet or thoracicoabdominal compression or decompression on expiratory phase could enhance expiratory turbulence and facilitate CO2 elimination in 9 dogs with steam-induced type I respiratory failure.
Qi
G
G
First Affiliated Hospital, Jiangxi Medical College, Nanchang.
Guo
G
G
Cao
Y
Y
D000818:Animals; D004285:Dogs; D005260:Female; D006611:High-Frequency Jet Ventilation / Q000379:methods*; D008297:Male; D011897:Random Allocation; D012129:Respiratory Function Tests; D012131:Respiratory Insufficiency / Q000628:therapy*