High frequency jet ventilation: intraoperative application in infants

The potential advantages of the intraoperative use of high frequency jet ventilation (HFJV) when compared with conventional ventilation (CV) include the maintenance of adequate gas exchange and lung function with a relatively motionless surgical field. To determine the pulmonary response to HFJV ventilation in infants during cardiac surgery, we evaluated lung function in nine infants supported with CV and HFJV during a Blalock-Taussig shunt procedure. Infants were randomized to each mode of ventilation with inspiratory and expiratory pressures and FiO2 held constant. Heart rate, blood pressure, arterial blood gases, pulmonary mechanics (lung compliance and resistance), and functional residual capacity (FRC) were compared after 10 minutes of stabilization of each ventilation mode, with the infants in the thoracotomy position and the surgical field adequately exposed. Pulmonary mechanics were measured using esophageal manometry and pneumotachography, and FRC by helium dilution. There was no difference in vital signs, pulmonary mechanics, FRC, or PaO2 on HFJV ventilation when compared with CV. Arterial PaCO2 was lower with a lower mean airway pressure on HFJV when compared with CV. The surgical team subjectively observed a diminished need for lung manipulation and improved ease of access to the surgical field with HFJV. These results indicate that the use of HFJV during closed-heart cardiac surgical procedures in infants provides similar cardiopulmonary stability and some potentially important clinical benefits when compared with CV.