Thoracic Epidural
Analgesia
Kristin Washburn
May 23, 2014
Conflicts of Interest
 None
Outline
 Background/history
 Physiologic benefits
 Current practice
 Current Research
 Fluoroscopy and epidurograms
 RCT
Timeline
 1885: Coring documented epidural anesthesia in animals
 1901: Sciard and Cattalin first use of epidural anesthesia
in form of a caudal
 1944: Vasconcellos use of epidural for thoracic surgery
 1948: Fujikawa presented 100 cases of TEA for thoracic
surgery
 1951: Crawford extended to 677 thoracic surgical cases
with the patient awake and spontaneously breathing
 1953: Crawford described catheter use for prolonging
anesthesia
 1956: Bonica described paramedian approach
O’Connor C J. Thoracic Epidural Analgesia: Physiologic Effects and Clinical Applications. Journal of Cardiothoracic and Vascular Anesthesia
7(5):595-609, 1993
Crawford OB: The technique of continuous peridural anesthesia for thoracic surgery. Anesthesiology 14:317-21, 1953
Hanging drop technique
Crawford OB, Ottesen P, Buckingham WW, Brasher CA: Peridural anesthesia in thoracic surgery. A review of 677 cases. Anesthesiology 12: 7395, 1951
Physiologic changes associated with
TEA
 Hypotension results from sympathetic blockade
 Decreased cardiac output due to decreased heart rate and
decreased contractility
 Decreased systemic vascular resistance
Stevens DS, Edwards WT (1991) Management of pain after thoracic surgery. In JA Kaplan (ed.) Thoracic Anesthesia (573) New York, NY:
Churchill Livingstone
Benefits of TEA
High risk surgical patients were found to have a reduction
in postoperative complications, incidence of cardiac failure
and major infectious complications.
Reduction in hospital costs
Yeager MP et al. Epidural anesthesia and analgesia in high-risk surgical patients. Anesthesiology 66: 729-736, 1987
Benefits of TEA- CARDIAC
decreased sympathetic activation from surgical stress
decreases myocardial oxygen demand and coronary artery
vasoconstriction
Moraca RJ, et al. The role of epidural anesthesia and analgesia in surgical practice. Annals of Surgery 23(5) 663-673, 2003
Liu S et al. Epidural Anesthesia and Analgesia Their role in postoperative outcome. Anesthesiology 1995 82: 1474-1506
Benefits of TEA- PULMONARY
decreased postoperative atelectasis, pneumonia and
hypoxemia
59% reduction in respiratory depression in patients treated
with TEA as compared with PCA
Moraca RJ, et al. The role of epidural anesthesia and analgesia in surgical practice. Annals of Surgery 23(5) 663-673, 2003
Ballantyne et al. The comparative effects of postoperative analgesic therapies on pulmonary outcome: cumulative meta-analysis of randomized,
controlled trials. Anesth Analg. 1998;86:598-612
Benefits of TEA- HEMATOLOGIC
Sympathetic stimulation
increases factor VIII, vWf,
decreases AT III and initiates
platelet activation
Bredbacka S, et al. Pre and postoperative changes in coagulation and fibrinolytic variables during abdominal hysterectomy under epidural or
general anesthesia. Acta Anaestheiol Scand. 1986; 30:204-210
Modig J et al. Role of extradural and of general anesthesia on fibrinolysis and coagulation after total hip replacement. Br J Anaesthe.
1983;55:625-629
Rem J et al. Postoperative changes in coagulation and fibrinolysis independent of neurogenic stimuli and adrenal hormones. Br J Surg.
1981;68:229-233
Benefits of TEA: GI
 Unopposed parasympathetic innervation of the gut
reduces post operative ileus that is caused by inhibitory
sympathetic efferent activation and narcotics
 Return of bowel function 2-3 days sooner in patients
with a thoracic epidural
Moraca RJ, et al. The role of epidural anesthesia and analgesia in surgical practice. Annals of Surgery 23(5) 663-673, 2003
Carpenter RL. Gastrointestinal benefits of regional anesthesia/analgesia. Reg Anesth. 1996; 21:13-17
Benefits of TEA: IMMUNE
 Stress response, inhaled anesthetics and opioids lead to
impairment of the immune system in the post operative
period
 Suppression of T cell, B cell, monocyte, neutrophil, NK cell
function
De Leon-Casasola OA. Immunomodulation and epidural anesthesia and analgesia. Reg Anesth. 1996; 21(6s):24-25
Meakins JL. Surgeons, surgery and immunomodulation. Arch Surg. 1991;126:494-498
Benefits of TEA: PAIN
 Pre-emptive analgesia from TEA reduces acute
post-operative pain
 TEA provides better postoperative analgesia
than opioids
 Acute post-operative pain is a predictor for
long-term pain after thoracotomy
Yegin A et al. Early post operative pain management after thoracic surgery; pre- and postoperative versus postoperative epidural analgesia: a
randomized study European Journal of Cardio-thoracic surgery 24; 2003:420-424
Katz J et al. Acute Pain after thoracic surgery predicts long-term post-thoracotomy pain. Clin J Pian 1996;12:50-5
Current practice
 Blind placement of thoracic epidurals
 Failure rate
 Epidurograms
 Fluoroscopic guidance of epidural steroid injections in
pain clinic
Riggs JR, et al. Epidural anesthesia and analgesia and outcome of major surgery: a randomized trial. Lancet 2002;359: 1276-1282
Ryu HG et al. The coiling length of thoracic epidural catheters: the influence of epidural approach angle. Br J Anaesth 2007; 98:401-404
Research Question
 Does the use of fluoroscopic guidance significantly
improve epidural function in patients undergoing a
thoracotomy?
Hypothesis
 Primary hypothesis:
 Precise epidural placement using fluoroscopic guidance will
improve overall catheter function leading to reduced
postoperative pain and analgesic requirements
 Secondary hypothesis
 Precise placement will reduce required volumes of local
anesthetic and local anesthetic related side effects including
hypotension and bradycardia, improving patient safety
Retrospective Review
 23 patients underwent
thoracotomy between May and
June 2011
 6 patients with thoracic epidural
placed blindly
 13 patients with thoracic epidural
placed under fluoroscopy
 4 patients without an epidural
All
Mean
STDev
Floro
Mean
STDev
No Floro
Mean
STDev
53.4
36.4
42.6
31.7
71.5
36.8
Study Design
 Randomized single blinded control trial
 Enrollment criteria: patients scheduled for thoracotomy
with no contraindication for epidural or fluoroscopy
 50 patients in each group:
 Treatment group: fluoroscopically placed epidural
 Control group: blind placement of epidural
Patient enrollment
135 patient enrolled
100 patients
participated in the
study
47 randomized to
fluoro placement
47 patients had
epidural placed
under fluoro
35 patient withdrew
from study
53 randomized to
blind placement
6 of the patients
randomized to blind
placement had
epidural placed
under fluoro
47 patients had
epidural placed
blindly
Reasons for patient withdrawal
• Surgery canceled [13]
• Patient did not require
epidural (thoracoscopy) [4]
• Two procedures [2]
• Patient decision [10]
• Allergy to contrast [1]
• Anticoagulation [1]
• Withdrawn anesthesia [2]
• Unable to place epidural [2]
Table 1: patient demographics
Table 1: Baseline Variables For The As Randomized Comparison
Control (N=53)
Fluroscopy (N=47)
Comparison
Variable
n or mean % or SD n or mean % or SD OR** or Difference 95% CI
Female
29
54.72
21
44.68
0.67
(0.28,1.58)
ASA
II
14
26.42
11
23.40
0.85
(0.31,2.32)
III
37
69.81
32
68.09
0.92
(0.36,2.35)
IV
2
3.77
4
8.51
2.37
(0.32,27.19)
Thoracotomy
51
96.23
45
95.74
0.88
(0.06,12.65)
Opiates Preop 9
52
17.31
5
46
10.87
Age *
64.7
9.1
65.3
10.6
0.6
(-3.4, 4.5 )
Weight *
81.5
20.2
79.5
20.7
-2.0
(-10.1, 6.2 )
presented as mean and SD. All others presented as n and percent. ** Odds Ratio
p-value
0.32
0.60
0.73
0.85
0.32
0.90
0.58
0.78
0.63
Outcomes measured
 Primary outcome: 24 hour morphine equivalent usage
 Secondary outcomes: 48 hour morphine equivalent
usage, 24 hour local anesthetic usage, functional
assessment using incentive spirometer, visual analog
scale, dermatomal level identified, hemodynamic
consequences of epidural including pressor use
Primary outcome: 24 hr ME
Comparison of Flouroscopy vs Control (Morphine Equivalents )
Unadjusted
Adjusted
Difference
95% CI
p-value
Difference
95% CI
p-value
(Control-Fluro)
(Control-Fluro)
As Randomized 24 Hr -1.40
(-14.18 , 11.37) 0.83
-4.60
(-15.18 , 5.99) 0.39
48 Hr 3.71
(-9.04 , 16.47)
0.57
-1.11
(-11.56 , 9.34) 0.83
As Treated
24 Hr 16.11
(-9.43 , 41.64)
0.22
4.88
(-8.11 , 17.88) 0.46
48 Hr 16.74
(-8.78 , 42.26)
0.20
3.45
(-9.35 , 16.26) 0.60
Positive differences reflect more morphine use in the control group. Models are adjusted for age, gender, ASA status, weight,
thoracotomy vs. VATA, and prior use of opiates.
Secondary outcomes
Table 2: Outcome Variables for the as Randomized Comparison
Control (N=53)
Fluroscopy (N=47)
Variable
n or
% or SD
n or
% or SD
mean
mean
Pressor infusion
8
15.09
19
40.43
Phenylephrine
31
58.49
31
65.96
Ephedrine
18
33.96
21
44.68
24 Hr Adjuvant Med
43
81.13
31
65.96
24 Hr O2 Requirement
29
54.72
28
59.57
24 hr ME
65.4
33.6
64.0
31.3
48 Hr ME
46.0
32.7
62.1
88.3
24 Hr VAS
4.3
2.5
3.8
2.4
PACU LOS (hours)
4.5
3.1
4.6
2.0
24HrLocalAnes
246.8
62.0
240.5
65.9
24HrMaxInfusionRate
5.2
1.4
5.0
1.3
EBL (ml)
264.2
447.1
232.8
293.4
Crystalloid (ml)
1705.7
852.7
1704.3
841.8
Colloid (ml)
31.7
139.3
21.7
103.1
24 hr Incentive
1039.5
470.6
1160.0
451.1
Spirometer
Average Heart Rate
71.9
10.8
69.6
9.7
Average MAP
81.9
7.4
80.1
6.6
OR** or
Difference
3.82**
1.38
1.57
0.45
1.22
-1.4
16.1
-0.5
0.1
-6.3
-0.2
-31.4
-1.4
-10.0
120.5
-2.3
-1.8
Comparison
95% CI
p-value
(1.35,11.36)
(0.56,3.37)
(0.65,3.82)
(0.16,1.23)
(0.51,2.92)
(-14.3,11.5 )
(-11.2,43.4 )
(-1.5, 0.5 )
(-1.0, 1.1 )
(-31.8,19.2 )
(-0.8, 0.3 )
(-180.6,117.8 )
(-338.1,335.3 )
(-58.8,38.8 )
(-94.5,335.6 )
<0.01
0.44
0.27
.084
0.62
0.83
0.24
0.29
0.92
0.63
0.46
0.68
0.99
0.69
0.27
(-6.4, 1.8 )
(-4.6, 1.0 )
0.26
0.20
Conclusions
 Preliminary retrospective review of fluoroscopic guidance
versus blind placement showed a 40% reduction in
morphine equivalent usage. The study was adequately
powered to show this difference but instead showed
equivalent morphine equivalent usage between groups
and no difference in secondary outcomes measured.
 During this time the acute pain service was started with
a select group of physicians dedicated to placement and
management of these epidural catheters.
 Things that may have made the
difference/improvement:
 Dedicated service to manage epidurals
 Smaller group of individuals with greater expertise placing
catheters
Research:
 Mentor and Co PI: Dr Parra
 Acute pain service team: Trish Barr, Kathy Bonham,
Kathy Lamb
 Acute pain service attendings
 Dr Yeager and Dr Loftus
 Dr Beach
 Kathy Gaudette in Pre admission testing
 CT surgeons: Dr Erkmen and Dr Nugent
 Residents, CRNAs and attendings who follow the protocol
with these patients in the OR
Thank you