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As the spectrum of cardiac surgeries has grown, the diversity and complexity of postoperative cardiac surgical care has also increased. This article examines 4 areas in critical care where clinical practice is evolving rapidly. Among these are management of mechanical ventilation, thresholds for blood transfusion, strategies for hemodynamic monitoring, and processes for central line insertion. Also reviewed are current approaches to common dilemmas in postoperative cardiac care: diagnosis of tamponade, and the diagnosis and management of low cardiac output states in patients with a ventricular assist device., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Introduction: The unique electromagnetic environment of the magnetic resonance imaging (MRI) scanner presents particular problems for critically ill patients requiring mechanical ventilation during MRI. Most currently available MRI-compatible ventilators are limited in scope and function and thus may not be suitable for patients requiring high peak inspiratory pressure or flow., Methods: To determine whether a standard critical care ventilator could be used under MRI conditions, we modified a Siemens Servo 900C by replacing the standard oxygen blender with an MRI-compatible blender. We then calibrated the ventilator and tested it on a mechanical lung during active MRI scanning at magnetic fields up to 1.5 tesla. After verifying adequate function, we used the ventilator to support 21 critically ill patients requiring mechanical ventilation during MRI., Results: In all cases we found no alterations in ventilator performance resulting from the electromagnetic interference typical of an MRI scan. We also found no abnormalities in the alarm systems for fraction of inspired oxygen, high inspiratory pressure, or minute volume. Finally, we found no degradation of MRI image quality resulting from ventilator operation during test scanning., Conclusions: We conclude that with minor modifications the Siemens 900C ventilator can safely ventilate critically ill patients during MRI.