Influence of low tidal volume ventilation on time to extubation in cardiac surgical patients.

BACKGROUND: Low tidal volumes have been associated with improved outcomes in patients with established acute lung injury. The role of low tidal volume ventilation in patients without lung injury is still unresolved. We hypothesized that such a strategy in patients undergoing elective surgery would reduce ventilator-associated lung injury and that this improvement would lead to a shortened time to extubation METHODS: A single-center randomized controlled trial was undertaken in 149 patients undergoing elective cardiac surgery. Ventilation with 6 versus 10 ml/kg tidal volume was compared. Ventilator settings were applied immediately after anesthesia induction and continued throughout surgery and the subsequent intensive care unit stay. The primary endpoint of the study was time to extubation. Secondary endpoints included the proportion of patients extubated at 6 h and indices of lung mechanics and gas exchange as well as patient clinical outcomes. RESULTS: Median ventilation time was not significantly different in the low tidal volume group; a median (interquartile range) of 450 (264-1,044) min was achieved compared with 643 (417-1,032) min in the control group (P = 0.10). However, a higher proportion of patients in the low tidal volume group was free of any ventilation at 6 h: 37.3% compared with 20.3% in the control group (P = 0.02). In addition, fewer patients in the low tidal volume group required reintubation (1.3 vs. 9.5%; P = 0.03). CONCLUSIONS: Although reduction of tidal volume in mechanically ventilated patients undergoing elective cardiac surgery did not significantly shorten time to extubation, several improvements were observed in secondary outcomes. When these data are combined with a lack of observed complications, a strategy of reduced tidal volume could still be beneficial in this patient population.

Management of a patient with lupus anticoagulant and antiphospholipid syndrome for off-pump coronary artery bypass grafting using the Hepcon system.

Patients with serum lupus anticoagulant antibodies (LAC) with or without antiphospholipid syndrome who present for cardiac surgery provide a unique set of challenges. Chief among these are the interference with anticoagulation monitoring by LAC. We present a case of such a patient who presented to us for coronary artery bypass grafting. We follow with a review of LAC and antiphospholipid syndrome and present a strategy for ensuring adequate anticoagulation during cardiac surgery in the background of previously published reports.

Intraoperative application of geometric three-dimensional mitral valve assessment package: a feasibility study.

OBJECTIVE: To study the feasibility of using 3-dimensional (3D) echocardiography in the operating room for mitral valve repair or replacement surgery. To perform geometric analysis of the mitral valve before and after repair. DESIGN: Prospective observational study. SETTING: Academic, tertiary care hospital. PARTICIPANTS: Consecutive patients scheduled for mitral valve surgery. INTERVENTIONS: Intraoperative reconstruction of 3D images of the mitral valve. RESULTS: One hundred and two patients had 3D analysis of their mitral valve. Successful image reconstruction was performed in 93 patients-8 patients had arrhythmias or a dilated mitral valve annulus resulting in significant artifacts. Time from acquisition to reconstruction and analysis was less than 5 minutes. Surgeon identification of mitral valve anatomy was 100% accurate. CONCLUSIONS: The study confirms the feasibility of performing intraoperative 3D reconstruction of the mitral valve. This data can be used for confirmation and communication of 2-dimensional data to the surgeons by obtaining a surgical view of the mitral valve. The incorporation of color-flow Doppler into these 3D images helps in identification of the commissural or perivalvular location of regurgitant orifice. With improvements in the processing power of the current generation of echocardiography equipment, it is possible to quickly acquire, reconstruct, and manipulate images to help with timely diagnosis and surgical planning.