The goal of anesthesia is to provide sufficient sedation to allow the procedure to be completed without excessive movement while avoiding cardiopulmonary instability. The issues pertinent to anesthesia outside of the OR for noncardiac procedures apply to cardiac procedures as well.
Aspiration thrombectomy with the AngioVac device (Vortex Medical) combines a venous suction cannula with VV bypass to achieve filtering of aspirated thrombus and other debris. This may be utilized to remove thrombi from the pulmonary vasculature, peripheral vasculature, or right atrium without the need for concomitant thrombolytic therapy.
Anesthetic management is driven by the indication of the procedure. Complications associated with acute PE, RV dysfunction, cardiac arrhythmias, venous embolic event, or previous failed thrombolytic therapy should be anticipated. General anesthesia with TEE and arterial line for invasive BP monitoring are indicated, with consideration given to central venous access.
VV bypass is established for filtering of thrombotic material and other debris. Patients are heparinized to ACT of 250 to 300 seconds before initiation. Access site for VV bypass should be discussed with the proceduralist, as right IJ access may be limited if the need for more central venous access should arise.
Implantable cardioverter defibrillator (ICD). Modern ICDs consist of an endocardial lead system and a pectoral pulse generator. Older systems used epicardial lead systems and abdominal generators.
ICDs are used for primary prevention of sudden cardiac death in patients with systolic heart failure (EF <35%) refractory to medical therapy or in those with high-risk conditions such as long QT
syndrome, hypertrophic cardiomyopathy, Brugada syndrome, and arrhythmogenic right ventricular dysplasia. In addition to ICD placement, patients with dilated cardiomyopathy and a widened QRS have been shown to also benefit from cardiac resynchronization therapy.Devices are placed under local anesthesia in the electrophysiology laboratory. A brief period of general anesthesia is necessary for testing the device once it is implanted. A deep sedation anesthetic with propofol is suitable.
If intracardiac electrodes are inadequate, patients may require intraoperative epicardial electrode placement. These patients are often hemodynamically compromised. They should have an arterial catheter and catheter for vasoactive medication administration. Emergency drugs, including epinephrine, must be immediately available.
Noninvasive programmed stimulation is used to test the function of an ICD after it has been implanted. An ICD programmer is used to induce the irregular rhythm (ventricular fibrillation or tachycardia). The device is then checked for proper sensing and dysrhythmia termination.
Cardioversion. A short-acting sedative (eg, propofol or etomidate) can be administered for brief loss of consciousness. The combination of fentanyl and midazolam is an alternative but not ideal due to prolonged duration of action. Routine fasting guidelines should be followed for all elective cardioversions. Hemodynamically unstable patients often warrant immediate cardioversion, and a small dose of amnestic may be all that can be tolerated.
Transcatheter ablation and electrophysiology procedures take place in cardiac catheterization or electrophysiology labs. Common procedures include pulmonary vein isolation (PVI) for ablation of atrial fibrillation/flutter, supraventricular tachycardia (SVT), and ventricular tachycardia (VT).
Anesthetic management is determined by the type of procedure performed. PVI is performed under general anesthesia, as more durable response to therapy has been documented as compared to PVI under conscious sedation. However, SVT ablations are carried out under sedation to avoid suppression of arrhythmia by a general anesthetic.