High frequency jet ventilation in experimental pulmonary emphysema.
The effects of high frequency jet ventilation (HFJV, f = 2 Hz and 8 Hz, I:E = 0.43, FiO2 = 0.4) were studied and compared with intermittent positive pressure ventilation (IPPV, f = 10-14 breaths/min, VT = 15 ml/kg, I:E = 0.5, FiO2 = 0.4) in 8 dogs before and after induction of panlobular emphysema (PLE). PLE increased alveolar-arterial PO2 difference (PA-aO2) during all modes of ventilation, whereas PaCO2 did not change significantly. In both periods of the study, HFJV8 Hz was less effective in terms of CO2-elimination and oxygenation. In the control-period, functional residual capacity (FRC) was 937 +/- 212 ml. The increase during HFJV (HFJV2 Hz: 1156 +/- 508 ml, HFJV8 Hz: 1153 +/- 433 ml) did not reach significance (P = 0.09). Closing volume (CV) increased from 1.5 +/- 4.3% of vital capacity (%VC) (IPPV) to 6.3 +/- 7.1%VC (HFJV2 Hz) and 10.8 +/- 9.8% VC (HFJV8 Hz), respectively. In the PLE-period, FRC and CV increased significantly to 1107 +/- 207 ml and 14.1 +/- 7.0% VC respectively during IPPV (P less than 0.05). Application of HFJV neither increased FRC (HFJV2 Hz: 1153 +/- 433 ml, HFJV8 Hz: 1005 +/- 344 nor CV 14.8 +/- 6.0% VC and 13.9 +/- 8.1% VC, respectively). It is concluded that HFJV induces no alveolar overdistension in dogs with emphysematous lungs.
Meyer
J
J
Klinik und Poliklinik für Anaesthesiologie und operative Intensivmedizin, Westfälische Wilhelms-Universität Münster, FRG.
Hachenberg
T
T
Lippert
G
G
Möllhoff
T
T
Wendt
M
M
D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D005069:Evaluation Studies as Topic; D006439:Hemodynamics; D006611:High-Frequency Jet Ventilation / Q000009:adverse effects / Q000592:standards*; D007385:Intermittent Positive-Pressure Ventilation / Q000592:standards; D011656:Pulmonary Emphysema / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D011659:Pulmonary Gas Exchange; D012129:Respiratory Function Tests