Regional anesthesia for cardiac surgery

1
Regional anesthesia for cardiac surgery

• John Butterworth, MD
• Professor Head
• Section on Cardiothoracic Anesthesia
• Wake Forest University School of Medicine
• Winston-Salem, North Carolina

http//www.wfubmc.edu/anesthesia/ 
Select Education and then click on
Brazil
2
Items for Discussion

• History of coronary surgery and epidural
  techniques
• Thoracic epidural analgesia for cardiac surgery
• Thoracic epidural anesthesia for cardiac surgery
• Spinal anesthesia and analgesia for cardiac
  surgery
• Are the risks small and the benefits large for
  regional techniques in cardiac surgery?
• Summary

3
History of epidural anesthesia

• 1885 J. L. Corning injects cocaine near spinal
  vessels probably epidural
• 1901 Sicard and Cathelin popularize caudal
  anesthesia
• 1921 Pages popularizes LEA
• 1932-3 Gutierrez and Soresi use hanging drop
• 1939 Forestier, Dogliotti describe loss of
  resistance
• 1976 Hoar et al use epidural to control
  hypertension after CABG
• 2000 Karagoz reports TEA for CABG

J. L. Corning
4
Items for Discussion

• History of coronary surgery and epidural
  techniques
• Thoracic epidural analgesia for cardiac surgery
• Thoracic epidural anesthesia for cardiac surgery
• Spinal anesthesia and analgesia for cardiac
  surgery
• Are the risks small and the benefits large for
  regional techniques in cardiac surgery?
• Summary

5
Potential advantages of thoracic epidural
analgesia for cardiac surgery

• Reduction of neuroendocrine stress response
• Effects on hemodynamics
• Metabolism
• Immune responses/SIRS
• Adverse effects of opioids
• Cardiac sympathectomy
• Improved GI motility
• Intense postoperative analgesia

Chaney. Ch 4 in Regional Anesthesia for Cardiac
Surgery, 2002 Liu, Carpenter, Neal.
Anesthesiology 1995821474-1506
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Potential advantages of thoracic epidural
analgesia for cardiac surgery

• Reduction of neuroendocrine stress response
• Cardiac sympathectomy
• Inhibit coronary vasoconstriction
• Improves collateral flow during ischemia
• Relief of angina in awake patients
• Additional benefit above ß-blockers
• Improved GI Motility
• Intense postoperative analgesia

Chaney. Ch 4 in Regional Anesthesia for Cardiac
Surgery, 2002 Liu, Carpenter, Neal.
Anesthesiology 1995821474-1506
9
(No Transcript)
10
Potential advantages of thoracic epidural
analgesia for cardiac surgery

• Reduction of neuroendocrine stress response
• Cardiac sympathectomy
• Improved GI Motility
• Intense postoperative analgesia

Chaney. Ch 4 in Regional Anesthesia for Cardiac
Surgery, 2002 Liu, Carpenter, Neal.
Anesthesiology 1995821474-1506
11
Effects of epidural anesthesia on
gastrointestinal system

• Inhibit nociceptive afferents
• Inhibit sympathetic efferents
• Increase blood flow to gut
• Effects from systemic absorption of LAs?
• After surgery (with continued LA dosing)
• Reduced postoperative opiates
• Increased peristalsis
• Better appetite
• Shorter length of stay after intestinal surgery?

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Potential advantages of thoracic epidural
analgesia for cardiac surgery

• Reduction of neuroendocrine stress response
• Cardiac sympathectomy
• Improved GI motility
• Intense postoperative analgesia
• Reduced respiratory depression relative to
  opioids, earlier extubation?
• Greater postoperative alertness
• Reduced persisting postoperative pain?

Chaney. Ch 4 in Regional Anesthesia for Cardiac
Surgery, 2002 Liu, Carpenter, Neal.
Anesthesiology 1995821474-1506
13
Prospective trial of thoracic epidural analgesia
after CABG
VAS Pain Score on POD 1

• 80 randomized to TEA vs iv morphine (MS)
• VAS pain scale
• Better pain scores, less postoperative stress
  depression with TEA
• Improved PaO2 and peak expiratory flow rate with
  TEA

Royse. Ann Thorac Surg 20037593-100
14
Significantly improved recovery with TEA after
CABG

• 420 patients
• Propofol-alfentanil with
• PCA morphine vs 0.125
• bupiv clon (0.6 µg/mL
• at 10 mL/h) for 96 hours
• Study patients similar at
• baseline (age, gender, number of coronary
  stenoses)
• More alert - less postoperative confusion with
  TEA

Scott. Anesth Analg 200193528-35
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No effect of TEA on recovery after cardiac
surgery with cardiopulmonary bypass

• 60 patients received general anesthesia with
  thiopental, relaxant, fentanyl, isoflurane
• Neostigmine glycopyrrolate at end of surgery
• 30 patients received epidural
• Puncture between T3 and T10 before induction
• 0.5 bupivacaine (5-7 mL) morphine 20 µg/kg)
• Postop 0.125 bupiv morphine 25 µg/mL 6 mL/h
• 30 patients received iv morphine per protocol

Fillinger et al J Cardiothorac Vasc Anesth
20021615-20
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No effect of TEA on recovery after cardiac
surgery with cardiopulmonary bypass

• Similar mean age (64, 62y), ejection fraction
  (60, 57), duration of cross clamp (56, 57 min)
  for GA vs. TEA
• More vasoconstrictors, fewer vasodilators used by
  TEA group
• No difference in cost or length of stay

Extubation time
N
Hours after surgery
Fillinger et al J Cardiothorac Vasc Anesth
20021615-20
17
No effect of thoracic epidural on incidence or
severity of persistent sternotomy pain

• Primary or re-do coronary surgery at Royal
  Melbourne Hospital (1997-1999) (n356)
• Either TEA (n217) or opioid analgesia (n139)
• 69 response (TEA n150, opioid n94) to survey
• 29 incidence of persistent pain (25 persistent
  sternotomy pain)
• No between group difference incidence (TEA 25,
  opioid 26) or severity of sternontomy pain

Ho et al. Anesth Analg 200295820-3
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Items for Discussion

• History of coronary surgery and epidural
  techniques
• Thoracic epidural analgesia for cardiac surgery
• Thoracic epidural anesthesia for cardiac surgery
• Spinal anesthesia and analgesia for cardiac
  surgery
• Are the risks small and the benefits large for
  regional techniques in cardiac surgery?
• Summary

19
Potential advantages of thoracic epidural
anesthesia for cardiac surgery

• Reduction of neuroendocrine stress response
• Cardiac sympathectomy
• Improved GI motility
• Intense postoperative analgesia
• Reduced respiratory depression relative to
  opioids, earlier extubation?
• Greater postoperative alertness
• Reduced persisting postoperative pain?
• No delay for extubation
• Rapid mobilization and recovery

Chaney. Ch 4 in Regional Anesthesia for Cardiac
Surgery, 2002 Liu, Carpenter, Neal.
Anesthesiology 1995821474-1506
20
Coronary artery bypass grafting in the awake
patient Three years' experience in 137 patients

• Oct 1998 Jan 2002
• 47 females, 90 males
• Target vessels
• LAD 122
• RCA 6
• LAD RCA 7
• LAD CFX 2

Karagoz et al. J Thorac Cardiovasc Surg
20031251204-7
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Coronary artery bypass grafting in the awake
patient Three years' experience in 137 patients

• Surgical approach
• Median sternotomy n63
• MIDCAB n74
• Rib cage lift n32
• H graft n42
• 132 of 137 completed procedure awake
• 58 patients bypassed the ICU
• Mean length of stay 1 day (range 0-3)

Karagoz et al. J Thorac Cardiovasc Surg
20031251204-7
22
Coronary bypass grafting via sternotomy in
conscious patients

• IRB approval
• Thoracic epidural
• Puncture at T1-T2 or T2-T3 one day before surgery
• Ropivacaine 0.5 sufentanil 1.67 µg/mL at 20-30
  mL/hr until block established, then 2-5 mL/hr
  during surgery
• Ropivacaine 0.16 sufentanil 1 µg/mL 2-5 mL/hr
  for postoperative analgesia

Meininger et al. World J Surg 200327534-8
23
Coronary bypass grafting via sternotomy in
conscious patients

• Mean dose of 17 mL ropivacaine-sufentanil during
  surgery
• 6 patients had IMA to LAD 1 patient had
  additional sequential jump graft to first
  diagonal branch
• 1 patient required tracheal intubation for
  respiratory distress
• Discharged after median 5 days (range 3-7)

Meininger et al. World J Surg 200327534-8
24
Thoracic epidural anesthesiafor OPCAB

• Oct 1999 Dec 2000, 10 patients had OPCAB with
  TEA alone
• No aspirin within 5 days of surgery
• Epidural placed at T2-T3
• Immediately before surgery
• Catheter threaded 5 cm craniad
• 15-20 mL of bupivacaine 0.5
• Midazolam 2.5 mg and ketamine 50 mg given for
  jugular line placement and vein harvesting

Vanek et al Eur J Cardiothorac Surg 200120858-60
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Thoracic epidural anesthesia for OPCAB

• Heparin 100 U/kg iv
• Total bupivacaine 20-25 mL total midazolam 5-10
  mg total ketamine 250-500 mg
• Bupivacaine 0.5 5 mL at 4-6 hr intervals for
  analgesia in first 24 hours
• Well tolerated in all patients
• Maximum length of stay 5 days

Vanek et al Eur J Cardiothorac Surg 200120858-60
26
Items for Discussion

• History of coronary surgery and epidural
  techniques
• Addition of epidural analgesia to cardiac surgery
• Thoracic epidural anesthesia for cardiac surgery
• Spinal anesthesia and analgesia for cardiac
  surgery
• Are the risks small and the benefits large for
  regional techniques in cardiac surgery?
• Summary

27
Spinal opioid analgesia after cardiac surgery

• Chaney reviewed 771 patients receiving
  intrathecal opioids
• All reports of small studies
• Intrathecal opioids produce reliable analgesia
• Unclear benefit to early extubation (some report
  delayed extubation)
• Only 7.6 of respondents to Goldstein used spinal
  techniques in cardiac surgery

Chaney. Anesth Analg 1997841211-21 Goldstein. J
Cardiothorac Vasc Anesth 200115158-68
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What impairs ventricular function after cardiac
surgery?

• Preexisting disease congenital, CAD, valvular
  disease, CHF
• Neuroendocrine response to anesthesia and surgery
• Systemic inflammatory response to CPB

• Chronic ischemia
• Stunning
• Hibernating myocardium
• ?1-AR downregulation

29
What impairs ventricular function after cardiac
surgery?

• Preexisting disease congenital, CAD, valvular
  disease, CHF
• Neuroendocrine response to anesthesia and surgery
• Systemic inflammatory response to CPB

• Chronic ischemia
• Stunning
• Hibernating myocardium
• ?1-AR downregulation

Could spinal anesthesia improve ventricular
function after cardiac surgery?
30
High spinal for cardiac surgery reduces ß-AR
downregulation
ß-AR Bmax

• Control vs 37.5 mg hyperbaric bupivacaine
• SPA group had reduced epi, norepi, cortisol vs.
  control
• When CPB gt1hr, less ß-receptor downregulation in
  SPA group

plt.02
Lee. Anesthesiology 200398499-510
31
Items for Discussion

• History of coronary surgery and epidural
  techniques
• Addition of epidural analgesia to cardiac surgery
• Thoracic epidural anesthesia for cardiac surgery
• Spinal anesthesia and analgesia for cardiac
  surgery
• Are the risks small and the benefits large for
  regional techniques in cardiac surgery?
• Summary

32
Thoracic epidural analgesia in coronary surgery
7 year experience

• N714 patients having CABG with CPB
• General anesthesia etomidate, fentanyl,
  cisatracurium volatile anesthetic
• Epidural
• T1-T2 or T2-T3 puncture on day of surgery
• Catheter threaded 3 cm into space
• 0.1 ml/kg ropivacaine 0.375 ropivacaine given in
  divided doses

Canto Pastor et al. J Cardiothorac Vasc Anesth
2003 17154-9
33
Thoracic epidural analgesia in coronary surgery
7 year experience

• Epidural infusion
• 0.2 ropivacaine 6 ml/hr intraoperatively
• 1 µg/mL fentanyl added to ropivacaine
  postoperatively

Canto Pastor et al. J Cardiothorac Vasc Anesth
2003 17154-9
34
Thoracic epidural analgesia in coronary surgery
outcomes

• 9 failed epidurals
• 6 dural punctures (used different site)
• Dopamine commonly used to maintain BP
• No epidural hematomas (95 confidence limit 3/714
  0.4)
• 20 myocardial infarcts 56 deaths

Extubation time
N
Canto Pastor et al. J Cardiothorac Vasc Anesth
2003 17154-9
35
Techniques for avoiding a rare adverse event
epidural hematoma

• Normalization of coagulation before
  instrumentation
• Avoid repeat attempts
• Postpone surgery for 24 hr after blood tap
• Perform tap gt1 hr before heparinization

• Optimize hemostasis after CPB
• Remove catheter with normal hemostasis
• Careful neurological surveillance
• ?Midline technique
• ?Saline through needle before catheter placed

Ho et al. Chest 2000117551-5
36
ASRA Neuraxial Anesthesiaand Heparin
AnticoagulationConsensus Statement

• Neuraxial techniques acceptable in patients who
  will receive heparin
• Avoid technique if other coagulopathies present
• Delay heparin gt1 hr after needle placement
• Remove catheter gt2 hours after last heparin dose
• Use minimal concentration of local anesthetic
• Use clinical judgement in event of bloody tap

ASRA Consensus Statements p6, 1998
37
Estimating the incidence of a rare adverse event
epidural hematoma

• Risk of epidural hematoma estimate to be lt1 of
  200,000 with epidural for noncardiac surgery
• More than 4,500 TEA procedures have been reported
  in cardiac surgery patients, with no reported
  hematomas
• 95 upper confidence limit is 3/N or 1/1500

Ho et al. Chest 2000117551-5
38
Items for Discussion

• History of coronary surgery and epidural
  techniques
• Thoracic epidural analgesia for cardiac surgery
• Thoracic epidural anesthesia for cardiac surgery
• Spinal anesthesia and analgesia for cardiac
  surgery
• Are the risks small and the benefits large for
  regional techniques in cardiac surgery?
• Summary

39
Regional anesthesia for cardiac surgery Summary

• Thoracic epidural effective, probably safe
  anesthesia for coronary bypass surgery
• Thoracic epidural provides good postoperative
  analgesia (not ideal for pain from saphenous vein
  or radial artery harvesting)
• Spinal anesthesia may attenuate ß-receptor
  downregulation (unknown importance)
• Spinal opioids effective for postoperative pain,
  probably safe
• Risk of hematoma small, but unknown

http//www.wfubmc.edu/anesthesia/  Select
Education and then click on Brazil
40
Uncoupling of ?1-ARs fromadenylyl cyclase after
CPB
pmol cAMP/mg protein

• Preserved number of receptors
• Reduced cAMP production
• in response to agonists
• No effect of prior CHF or
• ?-AR blockers on intraop
• uncoupling
• Defect localized to adenylyl
• cyclase

plt.005
Gerhardt. Circulation 199898II275-81 Booth.
Anesthesiology 199889602-11