Transesophageal echocardiographic assessment of pulmonary arterial and venous flow during high-frequency jet ventilation.
OBJECTIVE
To evaluate high-frequency jet ventilation (HFJV) effects on pulmonary arterial and venous flow compared to those of intermittent positive-pressure ventilation (IPPV) by using pulsed Doppler transesophageal echocardiography.


METHODS
Prospective clinical study.


METHODS
University-affiliated hospital operating room.


METHODS
13 ASA physical status I and II patients undergoing lower abdominal or lower extremity surgery.


METHODS
PATIENTS had total IV anesthesia with propofol and fentanyl. After anesthesia induction, a transesophageal echocardiography probe was inserted into the esophagus. IPPV (TV, 8-10 mL/kg; respiratory rate, 10-12 cycles/min; I/E ratio, 1:2; FIO(2), 1.0) and HFJV (driving pressure, 0.5-0.6 kgf/cm(2); frequency,3 Hz; I/E ratio, 1:1; FIO(2), 1.0) were performed under hemodynamically stable conditions.


METHODS
Pulmonary-arterial-flow velocity, pulmonary-venous-flow velocity, left ventricular short-axis view, and airway-pressure curve were recorded simultaneously. Parameters measured were: hemodynamic variables, arterial blood gases, inspiratory airway pressure; [from pulmonary-arterial-flow velocity] pre-ejection period (PEP), acceleration time (AT), right ventricular ejection time (RVET), and their ratios (PEP/AT, AT/RVET); [from pulmonary-venous-flow velocity] time-velocity integral of the first systolic wave (S1), second systolic wave (S2), and diastolic wave (D), and systolic fraction (integral S1 + S2/S1+ S2 + D); [from M-mode] left-ventricular-end systolic volume, left-ventricular-end diastolic volume (LVEDV), stroke volume, cardiac output, and ejection fraction, using Teichholz's method.


RESULTS
Peak inspiratory airway pressure during HFJV was significantly lower than that during IPPV. HFJV significantly decreased PEP/AT, correlating positively with pulmonary arterial pressure, and significantly increased AT and AT/RVET, correlating negatively with pulmonary arterial pressure. Systolic fraction, correlating negatively with left atrial pressure, increased significantly during HFJV, as did LVEDV, stroke volume, cardiac output, and ejection fraction.


CONCLUSIONS
Our results suggest that, in comparison to IPPV, HFJV significantly decreases pulmonary arterial pressure and left atrial pressure, resulting in significant increases in cardiac output and ejection fraction in healthy anesthetized adults.
Kawahito
S
S
Department of Anesthesiology, Tokushima University School of Medicine, Kuramoto, Japan. kawahito@bcm.tmc.edu
Kitahata
H
H
Tanaka
K
K
Nozaki
J
J
Oshita
S
S
D000005:Abdomen / Q000601:surgery; D000328:Adult; D001784:Blood Gas Analysis; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D006611:High-Frequency Jet Ventilation; D006801:Humans; D007385:Intermittent Positive-Pressure Ventilation; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D011652:Pulmonary Circulation / Q000502:physiology*; D011667:Pulmonary Veins / Q000000981:diagnostic imaging / Q000502:physiology*