Dr Priya Nair is a senior intensive care specialist at Sydney's St Vincent's Hospital and an expert in managing patients with cardiac assist devices. In this talk she takes us through the key issues encountered when on managing patients with left ventricular assist devices. As LVADs are becoming more widespread, this inside know-how is invaluable to all of us. They physiology and technology involved with these devices is pretty amazing. This is the second of two talks at the recent Sydney Intensive Network Meeting. The first talk was by Cardiologist Chris Hayward here.

1. Ventricular Assist Devices
Peri-operative Care
Approach to Emergencies
Priya Nair
Intensive Care Unit

5. Immediate Pre-operative
considerations

6. Haemodynamic optimisation
•
•
•
•
Comprehensive assessment of RV function
Pulmonary artery catheter
CVP<15
Lowering PVR to optimise right heart function,
reduce RAP & hepatic congestion
• Aggressively managing volume
to minimise RV workload
• Inotropes, vasodilators +/- IABP
• V-A ECMO as bridge to decision

7. •
•
•
•
•
•
Renal Function
Hepatic Function
Nutrition
Infection
Coagulation status
Neurologic, psychosocial & psychiatric
Slaughter M et al, Clinical management of continuous flow LVADs in advanced heart failure.
Journal of Heart & Lung Transplantation, Vol 29, No 4S, April 2010.

8. Intraoperative issues

9. TOE assessment
•
•
•
•
•
•
PFO/septal abnormalities
Aortic Incompetence- may be under-estimated
Mitral Stenosis
LV Thrombus
Ascending Aorta
?TV annuloplasty
•
Chumnanvej S et al, Echocardiography for VAD implantation
Anesth Analg 2007;105(583-601)
•
Scalia GM et al, Clinical utility of echocardiography in the management of
implantable ventricular assist devices. J Am Soc Echocardiogr 2000;13

10. PFO/ septal abnormalities

11. Aortic Reguritation

12. LV thrombus

13. Aortic atheroma

14. Tricuspid Regurgitation

15. Inflow cannula orientation

17. Chumnanvej S et al, Echocardiography for VAD implantation Anesth Analg 2007;105(583-601)

19. Pump placement - pre

21. Pump placement - post

22. Inflow & Outflow Doppler
Chumnanvej S et al, Echocardiography for VAD implantation Anesth Analg 2007;105(583-601)

23. Chumnanvej S et al, Echocardiography for VAD implantation Anesth Analg 2007;105(583-601)

24. Determinants of Flow

25. Speed adjustment
•
•
•
•
MAP>65 mm Hg,
Midline interventricular septum position
Intermittent aortic valve opening
No more than mild MR

27. Chumnanvej S et al, Echocardiography for VAD implantation Anesth Analg 2007;105:583-601

30. Right-sided circulation
•
•
•
•
•
High capacitance
Low –pressure
Short isovolumic contraction time
Near-continuous systolic ejection period
Less tolerant to afterload changes

31. Response to RV & LV to experimental changes in afterload
MacNee et al, AJRCCM 1994

32. • Lower sarcomere Ca++ concentrations with
reduced maximal shortening
• Less Ca++ sensitivity during inotropic
stimulation
• Compromises rapidly leading to hepatic
dysfunction & coagulopathy
• Increases peri-op mortality from 10-15% to
38-43%

33. • Peri-op- TX-A2, TNF-α, Interleukin & catechol
release during CPB, blood products,
inadequate cardioprotection, vasoconstrictors
can trigger RVF
• LVAD adds to this
– shifts inter-ventricular septum to left,
– distorts TV lead to TR
– improved CO & sudden increase in venous return

34. Management of RV dysfunction
•
•
•
•
•
•
•
•
Meticulous haemostasis/ avoid blood products
Avoid excess RV preload, diuretics
Decrease RV afterload- iNO, Iloprost
Inotropes- Adrenaline, Milrinone, Dobutamine
Vasoconstrictors- to maintain perfusion pressure
Pacing
Decrease pump speed
Consider RCA bypass &/or TV annuloplasty
• V-PA ECMO

35. Immediate post-op ICU
care

36. •
•
•
•
•
Fluids/inotropes
Suction events
RV dysfunction
Bleeding & anticoagulation
Tamponade

37. Suction event
Mauermann W J et al. Anesth Analg 2008;107:791-792

38. Cyclical LVAD suction
Speed (RPM)
Flow (L/min)
6
5
4
3
Positive pressure ventilation
2
PEEP 18cmH2O
2800
2700
2600
75
85
Time (seconds)
95

39. Fischer L et al Management of pulmonary hypertension Anesth Analg
2003;96:1603–16
Day/Month/Year
Footnote to go here
Page 39

40. Pericardial collection

42. V-PA ECMO

43. Weaning from V-PA ECMO

46. Take home messages
•
•
•
•
•
•
Pre-op haemodynamic optimisation
Meticulous care of the RV
Avoid over-pumping
Serial echocardiography is vital
Cautious anticoagulation
VADs are preload dependent & afterload
sensitive
• Mortality and persistent heart failure
determined by inefficient unloading of left side
and persistent RV dysfunction

47. At discharge
• Comprehensive education of patient & NOK
• Easy contact with VAD coordinator & hospital
team
• Spare controller & battery packs
• Strict BP control

48. Emergency Department
presentations
• EMS guide January 2012, Mechanical Circulatory Support
Organisation
• www.jems.com
• emcrit.org/wee/left-ventricular-assist-devices-lvads
• heartware.org
• mylvad.com

49. Call VAD centre

50. Check with NOK

51. • Bleeding
– Anticoagulation-related
– Abnormal von Willebrand factor
• Infection
– Driveline
– Pump pocket

52. VAD emergencies
Patient in Extremis

53. 1) AUSCULTATE FOR PUMP HUM

54. NO HUM
• Check cables and connections
• Check batteries

55. 2) CHECK MAP, ASSESS PERFUSION

56. 3) JUDICIOUS FLUID CHALLENGE
• Check pump flows and response.
<65mmHg- Adrenaline/Noradrenaline/Vasopressin
>65mmHg- Dobutamine/Milrinone
• Early arterial line with ultrasound guidance
• Care with CVC if RVAD in place

57. 4)MONITOR +/- DEFIBRILLATE
• Check electrolytes, correct potassium
• Avoid chest compressions

58. 5) URGENT ECHO
• RV small- hypovolaemia, bleeding, sepsis
• RV bigger than LV, D-shaped septum, TR- RV dysfunction
• Large LV (+MR)• High power- pump thrombosis (haemolysis, altered hum)
• Low power- inflow or outflow obstruction
• Ischaemic events
• Aortic Incompetence

59. AT ALL TIMES, BE GENTLE WITH THE RV

60. Pump flows & MAP OKLikely neurologic event

61. In short…
•
•
•
•
•
•
•
Call VAD centre
Check connections & cables
Auscultate for pump hum/doppler pulse
Check doppler BP, perfusion
Judicious fluid challenge, inotropes/pressors
Echo if possible
Consider non-VAD causes for presentation

62. Questions?