Choice of Anaesthesia for Patient with Cardiac Disease: General versus Regional?

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Choice of Anaesthesia for Patient with
Cardiac DiseaseGeneral
versus Regional?
K. Lebedinski St. Petersburg
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• Epidural anesthesia and analgesia exerted a
  significant beneficial effect on operative
  outcome in a group of high risk surgical
  patients
• Totally 53 high risk patients,
• Randomized between GA (25) and EAA (28) groups
• EAA group had a reduction in
• overall postoperative complication rate (P
  0.002),
• incidence of cardiovascular failure (P 0.007),
• major infectious complications (P 0.007),
• 24-h urinary cortisol excretion (P 0.025),
• hospital costs (P 0.02)

Yeager MP, Glass DD, Neff RK, Brink-Johnsen T.
Epidural Anesthesia and Analgesia in High Risk
Surgical Patients. Anesthesiology 1987 66
729-36
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A retrospective cohort study of 9425 consecutive
hip fracture patients, aged ?60 yr, who underwent
surgical repair at 20 US hospitals (1983-1993),
divided between GA (6206) and RA (3219)
groups The authors were unable to demonstrate
that RA was associated with better outcome than
was GA These results suggest that the type of
anesthesia used should depend on factors other
than any associated risks of mortality or
morbidity.
OHara DA, Duff A, Berlin JA, et al. The effect
of anesthetic technique on
postoperative outcomes in hip fracture repair.
Anesthesiology 2000 92 947-57
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Although clinical perceptions and theoretic
considerations suggest regional anesthesia should
be safer than general anesthesia in elderly
patients, current studies indicate no difference
in outcomes. Regional anesthesia may still prove
superior to general anesthesia if the right
patient population or right endpoints are
identified for comparison.
Roy RC Choosing general versus regional
anesthesia for the elderly. Anesthesiology
Clinics of North America 2000 18 91-104
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Epidural bupivacaine added to GA, despite of mild
hypotension, led to severe reduction in blood
flow distal to the experimental coronary stenosis
in swine.
Mergner GW, Stolte AL, Frame WB, Lim HJ.
Combined epidural analgesia and general
anesthesia induce ischemia distal to a severe
coronary artery stenosis in swine. Anesth Analg
1994 78 37-45
!
In 47 healthy parturients, underwent Cesarean
section under spinal anesthesia, 30 demonstrated
ST depression due to hyperkinetic contractile
state.
Roy L, Ramanathan S. ST-segment depression and
myocardial contractility during cesarean section
under spinal anesthesia. Can J Anaesth 1999 46
52-5
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So, where is Truth?...
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Neuraxial Block

• The primary event vasodilation, dose- and
  level-dependent
• Compensatory response cardiac output rise,
  sometimes reaching gt50 from baseline
• Possible limiting factors
• Hypovolemia
• High (gtTh5) central block level
• Fixed cardiac output (e.g., aortic stenosis)

!
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The Equilibrium of
Central Neuraxial Block

• Compensation
• Afterload decline ? LVESV decreases
• Baroreflex ? HR rise

• Decompensation
• Preload decline ? LVEDV decreases
• Block above Th5 ? cardiac depression

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General Anaesthesia

• The primary event cardiac output decline,
  reaching 25 of baseline
• Compensatory response vascular tone rise
• Possible limiting factors
• Low initial cardiac output
• Use of vasodilators
• Low central sympathetic outflow - inability to
  vasoconstriction

!
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The Equilibrium of
General Anaesthesia

• Decompensation
• Contractility falls ? VESV increases
• Central sympathetic outflow restricts ? Vascular
  tone depression

• Compensation
• Vascular tone rise
• Baroreflex ? HR rise

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Pre-operative Functional Tests

• Vladimir A. Schtange (1913)
• Inspiratory hold-up test (Schtange test)
• Physical exercise tests (treadmill,
  veloergometer, etc.)
• Pharmacological stress-tests
• Pre-op dipyridamol-thallium scintigraphy
  (Mangano et al.) ?...

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Why pre-op functional tests are unable to predict
complications?

• Challenges (e.g., physical exercise) are
  different from those at the OR!
• General conditions are different,
• Responses are also different,
• Criteria are based on another endpoints
• So, at least the challenges
• must be the same!

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Modeling

• Almost a universal tool, when the risk is high
  and possible losses are unacceptable
• Shipbuilding,
• Aviation,
• Nuclear power,
• Defense, etc

And what about anaesthesiology?...
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Our aim was to elaborate clinical prognostic
models to substantiate the individual choice of
anaesthesia based on specific patients response
to physiological challenges, similar to those of
the anaesthesia The first step was
Systemic Vasodilation with p.o. Nitroglycerin
as a Prognostic Test for Hypotension
after Spinal Block
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Problem
severe hypotension under spinal block
Aim of the study
to investigate the possibility of individual
prognosis based on the analogy between local
(spinal block) and systemic (nitroglycerin p.o.)
vasodilation
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Materials and methods

• 58 ASA I-III patients aged 2289
• Monitoring ECG, SpO2, NIBP
• Impedance cardiography CI, SVRI
• LV Power Index (W?m-2) 0.0022?CI?mean BP
• Nitroglycerin test 500 mkg p.o.
• Crystalloid fluid loading 6.2?3.8 ml?kg1
• Spinal anesthesia L3-L4, isobaric bupivacaine
  0.2?0.05 mg?kg1
• Mean sensory block level T8
• Hypotension mean BP lt75 of base level,
  requiring ephedrine

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Results

• Normotensive (N) group 44 patients
• Hypotensive (H) group 14 patients
• No difference between N and H age, gender, body
  weight and length, nitroglycerin and bupivacaine
  doses, time interval between test and puncture,
  sensory block level
• Similar response to test and SA
• Test CI rise (P5.5?10-5) N-group 42.9
• 
  H-group 22.2
• Test LVPI changes (P10-6) N-group 29.7
• 
  H-group 0.77

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Hemodynamic Response To
Nitroglycerin Test
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Conclusion
Preoperative systemic vasodilation test with p.o.
nitroglycerin may be used as simple, fast, safe
and relevant prognostic test for severe
hypotension after spinal block
Lebedinski K, Shevkulenko D Eur J Anaesth 2006
23, Suppl. 37 A408
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Our next steps
Esmolol i.v. bolus as a Prognostic Test
for Hemodynamic Response
to General Anaesthesia
Postural Tests as a Prognostic Tool
for Hemodynamic Responses
during Surgery and Anaesthesia
From á priori choice of anaesthesia to
modeling-based choice!
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The Choice of Anaesthesia
for Patient with Cardiac Disease Brief
Summary
Peripheral neuraxial block if sufficient
regarding surgery the superior choice anyway!
If there are no direct contraindications to
central neuraxial block choice between RA and
GA based on prognostic modeling tests
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Our specialty develops more and more methods of
anaesthesia ingenious, elegant and
effective. But we should always remember, that
the aim of our patient is to survive surgery, but
not to confirm any paradigm even those reported
just now!
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Thank you for the attention!