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VAD Guidelines for Anesthesia Raymond Graber, MD 10/26/2009 Preoperative Considerations Line placement: Arterial line: The left brachial artery is the preferred site in case the right axillary artery will be used for arterial cannulation. The radial and femoral arteries are acceptable alternatives, keeping in mind that radial lines tend to be damped and highly inaccurate in the period immediately following separation from cardiopulmonary bypass Peripheral IVs: Two large bore peripheral lines should be placed. Central lines: Use ultrasound to scan the right and left IJs. These patients may have had multiple IJ sticks in the past, and may have thrombosed veins or other abnormal anatomy. A MAC catheter is a good choice as an introducer – gives you an extra volume line. We have sometimes placed femoral dialysis catheters for access if other sites don’t give adequate IV access and blood loss is potentially higher (e.g. redo sternotomy) A PA catheter (preferably a CCO catheter) is placed Other Preop Issues: If the patient has an AICD and/or pacemaker make sure the EP service has been called to turn off the defibrillator and reprogram the pacemaker if necessary. If the patient is on a milrinone drip it should be discontinued. If the patient is very inotrope dependent start an epinephrine drip. Notify the respiratory therapist that nitric oxide will need to be set up for separation from bypass. If the patient is on coumadin find out if and when vitamin K (10 mg) needs to be given. Make sure all blood and blood products are ordered. 6 units PRBCs are ordered and prepared (10 units if patient has VAD or has been on coumadin). Blood should be leukocyte reduced. Cryo 10 units, plasma 6-10 units, and platelets 10 units are placed on hold, need to be in room when you come off pump Operating Room Set-up The setup is essentially the same as the standard cardiac setup. Vasoactive drips to be ordered include: nitroglycerine, neosynephrine, epinephrine, norepinephrine, vasopressin, methylene blue (2-3 mg/kg. Under body Bair Hugger should be on OR table. TEE machine and probe. 2 peripheral lines - at least one of these should be on a hot line with blood tubing; 1 line for cordis (lactated ringers); VIP line on mini dripper; triple set for A-line and PA catheter. Have Level-One also set up. Cerebral oximetry. Anesthetic Induction/Maintenance Most anesthesiologists will use etomidate as the induction agent of choice. Muscle relaxation is typically with succinylcholine, followed by pancuronium or vecuronium. Fentanyl is the usual narcotic. Most of these patients will not tolerate laying flat so anesthetic induction may have to be initiated with the patient in a head-up position. Antibiotics: Check with surgeons. Specific protocol for VAD patients. Usually Vancomycin, Zosyn, and Diflucan to continue 48 hours after incision. Antifibrinolytics: Amicar (10gms pre-pump; 10gms on-pump; 10gms post-pump). Hypotension can be multifactorial, but is frequently related to the use of ACE inhibitors, ARB’s, and milrinone. The vasodilatation induced by these agents can exacerbate anesthetic induced vasodilatation. Frequently an inotrope such as epinephrine will help to support the blood pressure as well as maintain the cardiac output until the patient can be put on bypass. An agent such as vasopressin or norepinephrine may be needed if the SVR remains excessively low. Methylene blue 2-3 mg/kg is also sometimes helpful. TEE can be useful to assess volume status and changes in contractility. TEE Evaluation: TEE is performed on all patients. The aortic and mitral valves are assessed for regurgitation. A PFO is looked for with color and by bubble study. LA and LV clots are searched for. RV function is assessed to determine the need for concommitant RVAD. Cardiopulmonary Bypass This period is managed as with any type of cardiac case. Vasopressors may be needed for blood pressure support in many instances. Glucose control is important and the blood glucose should be kept below 150 mg/dl with insulin boluses or an infusion. All factors and platelets should be prepared and in the room prior to termination of CPB. Nitric oxide is hooked up to the anesthesia circuit during this time as well. Prior to separation from cardiopulmonary bypass preemptive inotropic support should be started (i.e. epinephrine at 0.05-0.1 mcg/kg/min). Right heart support is important if only an LVAD is placed. Prior to separation from bypass TEE should be used to confirm adequate de-airing of the heart. Air has a tendency to make it’s way down the right coronary artery leading to right ventricular dysfunction. If this does occur, the systemic pressure should be raised to at least 80-90 mmHg to drive the air bubbles through the coronary circulation. This should be followed by a recovery period while still on bypass. Separation from Bypass If only an LVAD is placed, preservation of right ventricular function becomes a major priority. This goes along with aggressive management of pulmonary hypertension. The patients will come off pump on epinephrine and nitric oxide, and milrinone may be required if the patient has elevated PA pressures or the right heart is struggling. The right heart is monitored in several ways. The CVP is monitored continuously. The right heart can be seen on the surgical field. TEE is used to monitor size and function of the RV, and to assess for tricuspid regurgitation. If there is evidence that the right heart is failing, then it must be promptly addressed ( e.g. increasing epinephrine dose, adding milrinone, assessing that oxygenation and ventilation is adequate. Pressor support is frequently needed for vasodilatation related to ACE inhibitors, long bypass times, etc. Some patients (especially redos) will be coagulopathic. Keeping the patient warm (under body Bair Hugger, fluid warmers, increased ambient temperature, Alsius Temperature Management System) can prevent exacerbation of any ongoing coagulopathy.