Transcript Progress in Vascular Anesthesiology

Progress in Vascular
Anesthesiology
Donald M. Voltz, M.D.
Assistant Professor of Anesthesiology
Case Western Reserve University/University
Hospitals of Cleveland
Overview
Beta-blockers
Fluid Therapy
Regional Anesthesia
Beta-blockers in
Vascular Patients
Are We Using Too Few?
Вeta-Blockers
Cardioprotection
Hemodynamic Control
Anesthetic Modification
B-blockers and Cardioprotection
Well studied in vascular patient population
Evolving evidence supports there use as a
standard of care in at risk patients
Likely to find increasing role in the future
B-blockers Evidence for
Use
Effect of Atenolol on Mortality and Cardiovascular Morbidity after
Noncardiac Surgery
Dennis T. Mangano, Ph.D., M.D., Elizabeth L. Layug, M.D., Arthur Wallace, Ph.D., M.D., Ida Tateo,
M.S., for The Multicenter Study of Perioperative Ischemia Research Group
Volume 335:1713-1721
December 5, 1996
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Number 23
Mangano, et al. 1996
Randomized trial of esmolol vs. saline
(n=99, n=101)
Patient followed for 2 years
Mortality decreased in esmolol group
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0% vs 8% at 6 months
3% vs 14% at 1 year
10% vs 21% at 2 years
Wallace, et al. 1998
200 pts randomized to atenolol or saline
EKG, Holter monitor, and CPK w/ MB were
followed 24 hr prior and 7 days after
surgery
Atenolol 0,5, or 10 mg or placebo prior to
induction and every 12 hours until po than
qd for 1 week
Wallace, et al. 1998
Decreased perioperative myocardial
ischemia
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17/99 esmolol vs 34/101 placebo (days 0-2)
24/99 esmolol vs 39/101 placebo (days 0-7)
Polderman, et al. 1999
846 pts with one or more cardiac risk factors;
173 positive dobutamine stress tests
Bisoprolol in 59; Placebo in 53
Nonfatal MI
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0% bisoprolol
17% placebo group
Cardiac Death
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3.4% bisoprolol group
17% placebo group
What Patients are at
Risk
B-blockers & At Risk Patients
Presence of CAD
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History of Myocardial Infarction
Typical Angina or Atypical Angina with + Stress Test
At Risk for CAD (2 or more of the following)
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Age >65 years
Hypertension
Active Smoker
Serum Cholesterol > 240 mg/dl
Diabetes Mellitus
B-blockers and Cardioprotection
How well are we doing with at risk
patients?
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Not Very Well!
Prophylactic beta-blockade to prevent myocardial
infarction perioperatively in high-risk patients who
undergoing general surgical procedures.
Taylor RC, Pagliarello G.
Can J Surg. 2003 Jun;46(3):216-22
236 pts for laparotomy
143 pts at risk for CAD
60.8% did not receive B-blockers pre-op
33% pts had B-blockers discontinued
The Effect of Heart Rate Control on Myocardial
Ischemia Among High-Risk Patients After Vascular
Surgery
Khether E. Raby, MD, FACC*, Sorin J. Brull, MD , Farris
Timimi, MD, Shamsuddin Akhtar, MD, Stanley Rosenbaum,
MD, Cameron Naimi, BS, and Anthony D. Whittemore, MD
Anesth Analg. 1999 Mar;88(3):477-82
The Effect of Heart Rate Control on Myocardial Ischemia
Among High-Risk Patients After Vascular Surgery
Vascular Pts at High Risk for CAD
underwent 24 hrs Holter Monitoring
26 of 150 pts had significant ischemia as
measured by ST-depression – PreOp
Randomized to Esmolol gtt (n=15) or
Placebo (n=11)
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Titrated to HR 20% below ischemic threshold
Holter Monitoring for 48 hrs PostOp
The Effect of Heart Rate Control on Myocardial Ischemia
Among High-Risk Patients After Vascular Surgery
Ischemia Present PostOp
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73% in Placebo Group (8 of 11)
33% in Esmolol Group (5 of 15)
Number of Hours HR < Ischemic
Threshold
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9 of 15 pts in Esmolol group <20% and all
without ischemia
4 of 11 pts in Placebo group <20%. 3 of 4
without ischemia
B-blockers - Types
Esmolol
Metoprolol
Labetelol
Atenolol
Esmolol
Ultra-short acting
Quick onset (peak effect by 5 min)
Loading dose 0.5 mg/kg
Beta1 selective
IV route only
Expensive
Metoprolol
Can be given IV or PO
Long acting (q6h dosing)
Beta1 selective
Large doses may decrease the selectivity
Labetelol
Can be given PO and IV
Selective alpha1 and nonselective beta1,2
Alpha:Beta blocking properties 3:1 oral
and 7:1 IV. (not clinically seen)
Atenolol
Beta1 selective
Can be given IV or PO
B-blocker Adverse Reactions
Bradycardia – is it symptomatic???
Bronchospasm in COPD/Asthma patients
– no evidence to suggest problem in these
patients with selective agents
Heart Failure – use carefully in patients
with low EF, however, has been shown to
improve function with ACEI in end-stage
CHF
Summary for At Risk Patients
Preemptive Bradycardia
Think about heart rate as separate from
blood pressure
Be aggressive with heart rate control
Incorporate into preoperative and
postoperative care.
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Involve Primary Care Physician
Involve Vascular Surgeon and Nursing
Balanced Anesthesia and
Beta-blockers
Analge s ia
Am ne s ia
Components of Balanced Anesthesia
3/15/2003 - v2
Uncons cious ne s s
He m odynam ic Control
Paralys is
B-blockers and
Anesthetic Reduction
Esmolol Promotes
Electroencephalographic
Burst Suppression During
Propofol/Alfentanil
Anesthesia
Jay W. Johansen
Anesth Analg 2001; 93:1526-31
Esmolol Promotes Electroencephalographic Burst Suppression During
Propofol/Alfentanil Anesthesia
N=20 patients
Alfentanil Groups (50 or 150 ng/ml)
Saline vs Esmolol infusion
Monitored BIS output and Suppression
Ratio
Esmolol Promotes Electroencephalographic Burst
Suppression During Propofol/Alfentanil Anesthesia
BIS Output
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Esmolol – 40% reduction (37→22)
Saline – no change
Suppression Ratio
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Esmolol – 13.4 fold increase (5 → 67)
Saline – no change
Efficacy of esmolol versus
alfentanil as a supplement
to propofol-nitrous oxide
anesthesia
Smith, J. Van Hemelrijck, and P. White
Anesth Analg 2003;97:1633-1638
Efficacy of esmolol versus alfentanil as a supplement to propofolnitrous oxide anesthesia
N=97 patients for arthroscopy
Compared esmolol to alfentanil
Efficacy of esmolol versus alfentanil as a supplement to
propofol-nitrous oxide anesthesia
Esmolol decreased time to eye opening
(7.2 vs 9.8 min)
Esmolol reported more pain in PACU
Esmolol required more opiods in PACU
Esmolol Potentiates
Reduction in Minimal
Alveolar Isoflurane
Concentration
Jay W. Johansen, et al.
Anesth Analg 1998; 87:671-6
Esmolol Potentiates Reduction in Minimal Alveolar
Isoflurane Concentration
N=100; divided into 5 groups
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Isoflurane alone
Isoflurane with large dose esmolol (250
mcg/kg/min)
Isoflurane with Alfentanil
Isoflurane, Alfentanil, small dose esmolol (50
mcg/kg/min)
Isoflurane, Alfentanil, large dose esmolol (250
mcg/kg/min)
Esmolol Potentiates Reduction in Minimal Alveolar
Isoflurane Concentration
MAC levels after steady state
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Isoflurane – 1.28%
Iso + large dose Esmolol – 1.23%
Iso + Alfentanil – 0.96%*
Iso + Alfentanil + small dose Esmolol – 0.96%
Iso + Alfentanil _ large dose Esmolol –
0.74%**
Beneficial Effects from B-Adrenergic Blockade in
Elderly Patients Undergoing Noncardiac Surgery
Michael Zaugg, M.D.; Thomas Tagliente, M.D., Ph.D.; Eliana Lucchinetti, M.S.; Ellis
Jacobs, Ph.D.; Marina Krol, Ph.D.; Carol Bodian, Dr.P.H.; David L. Reich, M.D.; Jeffrey
H. Silverstein, M.D.
ANESTHESIOLOGY 1999;91:1674-1686
Beneficial Effects from B-Adrenergic Blockade in
Elderly Patients Undergoing Noncardiac Surgery
N=63 patients for noncardiac surgery
Monitored – Neuropeptide Y, epinephrine,
norepinephrine, cortisol, and ACTH
Randomly assigned
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Group 1: no atenolol
Group 2: Pre- and Post-operative atenolol
Group 3: Intraoperative Atenolol
Beneficial Effects from B-Adrenergic Blockade in
Elderly Patients Undergoing Noncardiac Surgery
Beta-blockade did not change
neuroendocrine stress response
Lower Narcotic Requirement
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Groups II and III – 27.7% less fentanyl
Lower Anesthetic Requirements
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Group III – 37.5% less isoflurane (BIS same in
all groups)
Lower PACU Morphine requirements
Shorter PACU times
Beta-blockers and Bariatric Surgery
Randomized Study of Morbidly Obese
Patients Undergoing Gastric Bypass
Metoprolol vs. Placebo
Evaluate
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Intraoperative Volatile Requirements
PACU Pain Requirement
PCA Usage
Fluid Therapy for
Vascular Patients
Are We Using Way Too Much?
AAA Change in Anesthetic Care
Retrospective study of AAA and
anesthesia
Patients for elective infra-renal AAA in
1991 and 2001
End-Points
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Time to extubation
Intraoperative Fluid Administration
Time to return of Bowel Function
AAA and Crystaloid Use
Crystalloid (cc)
8000
6000
1991
4000
2001
2000
0
1991
2001
AAA Length of Stay
12
10
8
6
4
2
0
1991
2001
ICU LOS (days)
Hospital LOS
(days)
AAA and Bowel Function
180
160
140
120
100
80
60
40
20
0
1991
2001
NG Tube
Removal
Clear
Liquid
Intake
Regular
Diet
Intake
Fluid Therapy in Vascular Patients
Ensure adequate end-organ perfusion
Treat hypotension of reperfusion with a
combination of fluid and vasopressors
Replace blood loss with blood, not
crystaloid
Question replacing insensible losses and
NPO deficits by formulas.
Vascular Surgery and
Regional Anesthesia
Benefits of Regional Anesthesia
Cardiac Protection
Preservation of Pulmonary Function
Lower graft thrombosis
Decrease postoperative hypercoagulable
state
Faster return of bowel function
Superior postoperative analgesia
Better immune function
Regional Anesthesia and Cardiac
Protection
Thoracic epidural a must, no benefit from
lumbar catheter
High level to block cardiac accelerator
fibers
Maintain an infusion or PCEA postoperatively for maximal benefits
Low risk of bleeding if placed 1 hour prior
to systemic heparinization
Regional Anesthesia and Cardiac
Protection
Still not clear
Some studies show no difference
The role of beta-blockers to control
sympathetic response confounding
No clear evidence regional is superior
Regional Anesthesia and Cardiac
Protection
Problems with regional anesthesia studies
and cardiac protection
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Groups not normalized to heart rate?
Is the benefit only from cardiac accelerator
fibers being blocked?
Are there other benefits of beta-blockers not
being used because of a high epidural level?
Is Reduced Cardiac Performance the
Only Mechanism for Myocardial
Infarction Size Reduction During
beta-Adrenergic Blockade?
Stangeland, L. Grong, K. Vik-Mo, H.
Anderson, K. Levken, J.
Cardiovasc Res 1986;20: 322-30
Stangeland, et al.
Anaesthetized cats to elucidate if
decreased heart rate was the mechanism
for cardiac protection.
Treated groups with either timolol or
alinidine (clonidine derivative that
decreases HR independently of Betareceptors)
Induced regional ischemia (LAD occlusion
for 6 hours)
Stangeland, et al.
Alinidine Group:
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Decreased Necrotic Area to 77% of control
Timolol Group:
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Decreased Necrotic Area to 65% of control
This data suggested another mechanism for
beta-blocker cardioprotection other than heart
rate control
Regional Anesthesia and
Pulmonary Function
FRC is decreased due to
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Diaphragmatic dysfunction of upper
abdominal or thoracic incisions
Decreased chest wall compliance
Incisional Pain Limitations
Regional Anesthesia and
Pulmonary Function
Advantages for thoracic and upper
abdominal surgery
Unclear benefits in lower abdominal and
peripheral surgery
No Change in hospital LOS
Time and Post-Op labor intensive
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Time to place
Requires pain service to follow
Regional Anesthesia and
Pulmonary Function
Currently are not using thoracic epidurals
for AAA surgery
Pain control in ICU and on Floor is
adequate
Surgeon’s and Anesthesiologist’s are in
agreement to post-operative pain control
Regional Anesthesia and
Pulmonary Function
No increased incidence in pneumonia
No delay in extubation for elective aortic or
lower extremity surgery
Regional Anesthesia and Graft
Thrombosis
Improvement in lower extremity blood flow
Decrease sympathetic activation and stimulation
of coagulation system
Systemic absorption of local anesthetics block
thromboxane A2, platelet aggregation and
reduce blood viscosity
Large meta-analysis done in orthopedics looking
at DVT.
Abdominal surgery patients had a less
significant effect
Minimization of blood loss.
Regional Anesthesia and LOS
No increase in LOS at our institution
Unclear in literature if LOS is improved
with regional anesthesia
Double-masked Randomized Trial Comparing
Alternate Combinations of Intraoperative
Anesthesia and Postoperative Analgesia in
Abdominal Aortic Surgery
Norris, E.J. et al.
Anesthesiology 2001;95:1054-67
Norris et al.
N=168 pts for elective aortic surgery
Randomized to either epidural with light
GA vs. GA alone
Pts either with PCA or PCEA for 72h
postoperatively
Norris et al.
Postoperative outcomes were similar in
groups
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MI, reoperation, renal failure, pneumonia
LOS and direct medical costs
VAS Pain Scores
Epidural groups with shorter
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Time to extubation (19 vs. 13 hours)
ICU discharge (46 vs. 43 hours)
Return of Bowel Function (111 vs. 102 hours)
Regional Anesthesia and Bowel
Function
Thought to relate to narcotic use as well
as sympathetic reflex arcs
Thought is decreased sympathetic slowing
while maintaining parasympathetic
peristalis
Problems with randomized studies are
higher amounts of narcotics.
Lower narcotic usage has impacted postoperative ileus in out institution
Regional Anesthesia and Vascular
Surgery - Summary
Not presently known if regional superior to
beta-blockade for cardioprotection
Regional may be beneficial in severely
reduced pulmonary function patients
Pain control is similar with IVPCA vs
PCEA
Unclear if additional factors are significant
in vascular patients
THE END
Vascular Anesthesia at University Hospitals of
Cleveland