Cardiac anesthesiologists and LVAD patients: Pro vs Cons

There’s been a big debate re: who should care for LVAD patients… a general anesthesiologist or a cardiac anesthesiologist?  See below for pros and cons of each.  Ultimately, I think all anesthesiologists should be comfortable caring for these patients as we’ll see more and more LVAD patients undergoing procedures.

Troubleshooting the Left Ventricular Assist Device.  Emergency Medicine. 2016 February;48(2):58-63.

RTEmagicC_em048020061_t1.jpg
From Emergency Medicine, Feb 2016.
LVAD Parameter Abnormalities:
  • High power, low-pulsatility index and fluctuating pump speed: Consider pump thrombosis or hypotension, vasodilation, initial response to exercise.
  • High power with high pulsatility index: Consider fluid overload, normal physiological response to increased demand; myocardial recovery.
  • Low power, low pulsatility index, and unchanging speed: Consider hypertension or inflow/outflow obstruction, LV failure, dysrhythmia.
  • Low power with normal or high pulsatility index: Consider suction event.

Pro: Cardiothoracic Anesthesiologists Should Provide Anesthetic Care for Patients With Ventricular Assist Devices Undergoing Noncardiac Surgery. JCVA, February 2017. Volume 31, Issue 1, Pages 378–381

Con: Cardiothoracic Anesthesiologists Are Not Necessary for the Management of Patients With Ventricular Assist Devices Undergoing Noncardiac Surgery. JCVA, February 2017. Volume 31, Issue 1, Pages 382–387.


VAD-2
From LifeInTheFastLane.com

Ventricular assist devices and non-cardiac surgery.  BMC Anesthesiology201515:185

  • Goals of care for LVAD patients undergoing non-cardiac surgery should be directed at maintaining forward flow and adequate perfusion. Three main factors that affect LVAD flow are preload, RV function, and afterload.
  • The right ventricle is the primary means of LVAD filling; therefore, maintaining RV function is imperative.
  • Marked increases in systemic vascular resistance should be avoided.
  • Generally, decreases in pump flow should first be treated with a fluid challenge. Hypovolemia should be avoided and intraoperative losses should be replaced aggressively. Second line treatment should include inotropic support for the right ventricle.
  • Low-dose vasopressin (<2.4 U/h) may be the vasopressor of choice due to its minimal effect on pulmonary vascular resistance.
  • Standard Advanced Cardiovascular Life Support Guidelines should be followed; however, external chest compressions should be avoided during cardiac arrest.
  • Steep Trendelenburg may increase venous return, risking RV strain. Peritoneal insufflation for laparoscopic surgery also increases afterload and has detrimental effects on preload.  Insufflation should utilize minimum pressures and be increased in a gradual, step-wise fashion.
  • TEE can be extremely valuable in diagnosing the cause of obstruction.

Perioperative management of patients with left ventricular assist devices undergoing noncardiac surgery. Annals of cardiac anaesthesia 2016. Vol 19, Issue 4: 676-686.

LVAD: What Should I report? Feb 2017 ASE conference. **ECHO**

  • Higher the RPMs (pump speed)
    • More LV compression, smaller LV size
    • Less functional MR
    • More AI, less AV opening
    • Less LVED diameter
  • De Novo Aortic Regurgitation Post LVAD
    • Proposed mechanisms
      • Aortic valve remains closed during systole
      • Commissural fusion of the aortic valve from disuse
      • Subsequent degeneration of valve
      • Turbulent blood backflow from small outflow cannula onto a closed valve
      • Persistent elevation of aortic root pressure –> aortic root dilation and valve incompetence
    • Treatment
      • Lower LVAD speed (but that may worsen mitral regurgitation)
      • Aortic valve surgery or percutaneous intervention
      • Heart transplant
  • RV Fractional Area Change (RV FAC)
    • RVFAC is a rough measure of RV systolic function (4 chamber view)
    • RVFAC = (RVEDA – RVESA) / RVEDA
    • Normal RVFAC = 35 – 63%

Ventricular Assist Device (VAD). LifeInTheFastLane.com. .

Care of the LVAD patient PPT. Summit 2014.

  • Pulsatility Index:
    • —normally decrease as pump speed is increased

LVAD: Understanding equipment and Alarms. Duke Heart Center PPT.

LVAD Management in the ICU. Crit Care Med 2014; 42:158–168. 

Screen Shot 2018-11-26 at 11.20.26 AM
From Left Ventricular Assist Device Management in the ICU Pratt, Alexandra K. MD1; Shah, Nimesh S. MD1; Boyce, Steven W. MD2 Critical Care Medicine: January 2014 – Volume 42 – Issue 1 – p 158–168 doi: 10.1097/01.ccm.0000435675.91305.76 Concise Definitive Review
Screen Shot 2018-11-26 at 11.20.47 AM
Left Ventricular Assist Device Management in the ICU Pratt, Alexandra K. MD1; Shah, Nimesh S. MD1; Boyce, Steven W. MD2 Critical Care Medicine: January 2014 – Volume 42 – Issue 1 – p 158–168 doi: 10.1097/01.ccm.0000435675.91305.76 Concise Definitive Review

 

Anesthesia for Left Ventricular Assist Device Insertion: A Case Series and Review. Ochsner J. 2011 Spring; 11(1): 70–77.

Medical Management of Patients With Continuous-Flow Left Ventricular Assist Devices. Curr Treat Options Cardiovasc Med. 2014 Feb; 16(2): 283.

 


My blog posts:

HeartWare vs. HeartMate LVAD

Ventricular Assist Devices: Impella

Left Ventricular Assist Device #LVAD

Ventricular assist device
Image via Wikipedia

The other day, I had the opportunity to participate in a LVAD case. In simple terms, this LVAD device is placed into patients whose heart needs extra assistance pumping blood to the body. Typically, these patients have or are failing medical therapy and are either on the heart transplant list waiting for a heart or are permanently placed on an LVAD.

A patient emergently came to the OR for an LVAD as he had several episodes of VTach overnight. His heart function was pretty minimal (EF10%, global hypokinesis with akinesis along the apex, LV dilatation, severe MR, PASP 40s-50s). Additionally, he was on an Intra-aortic Balloon Pump (IABP) to help assist his failing heart. He also had a femoral pulmonary catheter. We wheeled him from the ICU to the OR. He was on phenylephrine, dobutamine, and milrinone. The next challenge was transferring him from the ICU bed to the OR bed without disconnects (IABP, IV, etc) or sending him into VT. The lines were meticulously detangled while maintaining current cardiac infusions. Anesthetic induction would have to be cautious. Luckily, he had been NPO from the prior evening. I worked in a little bit of midazolam through his femoral venous line (while observing the femoral IABP a-line). Then gave some lidocaine and etomidate. He seemed to still be doing ok, worked in a bit of fentanyl and was able to mask him well. Upon good mask ventilation, I administered rocuronium and secured the airway with an 8.0ETT. Next organizational thought: where to go for additional venous access? He had a Left chest AICD, a Right IJ hemodialysis catheter. Therefore, I opted for a L IJ 9Fr introducer and we could float a PA cath after the case (we could use the femoral PA cath during the case). He received vancomycin and cefuroxime for antibiotic prophylaxis. The next challenge would be sternotomy as he had a previous 4 vessel CABG several years prior. Prior to skin incision, I worked in more fentanyl. After a careful sternotomy, dissection ensued. The heart and vessel grafts were pretty socked in. The surgeon was able to continue and prepare the heart and LVAD components. Aminocaproid acid was given. We went on cardiopulmonary bypass (CPB). We maintained the patient on milrinone, dobutamine, vasopressin, and nitric oxide (yes, breathing smaller tidal volumes on CPB). Additionally, we gave several packed cells on CPB and started DDAVP infusion. The real test would be coming off CPB…and catching up to all the bleeding. Initially, separating from CPB was a bit cautious. The patient needed more volume to prevent the LV from being sucked down with the LVAD. The perfusionist was able to give the patient back volume since the cannulas were still in. The oozing was still going. We continued to hang blood product (PRBC, FFP, platelets). We gave the protamine, the aortic cannula was removed. However, at times, we were still behind in volume. The surgeon cut one of the venous cannulas and hooked up the aortic cannula into the “venous” cannula to give volume back to the patient. Finally, after multiple periods of packing and waiting…the surgeons were able to cose the chest. We went through 15U PRBC, 15U FFP, 12U plt, 2 rounds of DDAVP infusion, 30g Amicar + amicar infusion, 7g calcium, some bumetanide, magnesium,etc. We took the patient to the SICU after the case. He was stable, maintaining his BP and Hct. It was a great case in transfusion therapy, cardiac physiology (pre-LVAD and post-LVAD), and OR teamwork. I can’t emphasize the OR teamwork enough: there was such great communication in the OR (nurses, scrub, anesthesia tech, surgeons, perfusionist, and anesthesiologists). This is the type of practice one dreams of… where camaraderie and work go hand-in-hand. So glad I found it!