Principles of Surgery
PERI-OPERATIVE
ANALGESIA
Joseph Kay, MD FRCPC
Sunnybrook & Women’s College HSC
Assistant Professor, University of Toronto
Why should we treat
peri-operative pain?
 pain and suffering
  complications
  likelihood of chronic pain
  patient satisfaction
  speed of recovery  LOS cost
  productivity and quality of life

Adverse effects of poor pain
management

Cardiovascular
 Respiratory
 Gastrointestinal\Genitourinary
 Neuroendocrine\Metabolic
 Musculoskeletal
 Immunological
 Psychological
Current pain management
Pain can virtually be eliminated with minimal side
effects
BUT

70% inpatients still have moderate or severe pain
 40% outpatients have significant pain in 1st 24 h
WARFIELD Anesthesiol 1995 83:1090
BEAUREGARD Can J Anesth 1998 45:304
Barriers to effective pain
management I
ANESTHESIOLOGIST

Inadequate pain education
 Underestimation analgesic requirements
 Failure to recognize patient variability
 Inadequate use local\regional techniques
 Complications from side effects
Barriers to effective pain
management II
PATIENT

Expectation of severe pain
 Inadequate pain education
 Analgesic side effects
 Fear of addiction
Barriers to effective pain
management III
NURSE

Expectation of severe pain
 Inadequate pain education
 Fear of causing analgesic side effects e.g
respiratory depression, addiction
 Insufficient time for assessment/ treatment
Barriers to effective pain
management IV
SURGEON
Belief that pain is ‘normal’ and not harmful
 Concern that pain may mask injury
 Inadequate pain education
 ‘Don’t ask don’t tell’
 Complications from side effects\addiction

Barriers to effective pain
management V
HOSPITAL

Inadequate funding & resources with pain
as low priority
 Inadequate commitment
 Lack of accountability
Traditional opioid analgesia

Parenteral
 prn
Traditional opioid analgesia







Sedation
Respiratory depression
Nausea & Vomiting
Urinary retention
Ileus
Constipation
Pruritus
Multimodal Analgesia
Using more than one drug, acting at a
different place or with a different
mechanism, each with a lower dose than if
used alone, thus providing better analgesia
with less side effects.
Multimodal Analgesia





Opioid
NSAID (COXIB)
Acetaminophen
Local anesthetic block
Other adjuncts
Multimodal Analgesia
Multimodal Analgesia





Better analgesia
Less side effects
Can decrease hospital stay
May improve surgical outcome
May decrease chronic pain
KEHLET Br J Surg 1999 86:227 CAPDEVILLA Anesthesiol 1999 91:8
REUBEN Anesthesiol 2001 95:390
Multimodal Analgesia
Opioids

Systemic - oral/parenteral/transdermal
 Neuraxial - spinal/epidural
 Peripheral - intra-articular, periosteal
Multimodal Analgesia
Opioids
Sites of action

Central: dorsal horn spinal cord
 Peripheral: synovium
periosteum
Multimodal Analgesia
Opioids
Systemic

Oral contin + b/t
 Parenteral - iv PCA
sc infusion + b/t
Multimodal Analgesia
Opioids
Neuraxial

Spinal - single shot
 Epidural - continuous infusion
(+local anesthetic)
Multimodal Analgesia
Opioids
Peripheral

Intra-articular
 Iliac crest bone graft
Opioid
Intraoperative vs Postoperative
THA 40 pts
Intra-operative group:



achieved VAS<3 42 vs 76 min
 morphine PACU 7 vs 15 mg
 respiratory depression
PICO Can J Anesth 2000 47:309
Opioid
Oral Controlled Release
Oxycontin

TKA 59 pts
 29 oxycontin vs 30 placebo
 Oxycodone q4h prn
 Oxycontin group:  pain  LOS 2.3 days
ROM
CHEVILLE J Bone Jt Surg Am 2001 83A6:915
Opioid
Iliac Crest Infiltration
Spine fusion 60 pts
Group I: saline into donor site
Group II: 5 mg i.m morphine
Group III: 5 mg morphine into donor site
Opioid
Iliac Crest Infiltration
Gp III 50% less morphine 24h
lower pain scores > 2h
 pain at 1 yr 5% vs 33%
REUBEN
Anesthesiol 2001 95:390
Multimodal Analgesia
NSAID / COXIBS

potent analgesics for mild-moderate pain
 adjunct to opioid for moderate-severe pain




 VAS 2/10
 opioid consumption 30-50%
 opioid related side effects
NSAID
Spinal fusion
Morphine PCA
70 pts
ketorolac 0-30 mg iv q6h
Ketorolac 7.5-30 mg:
  morphine use
  pain VAS
  sedation  nausea
REUBEN Anesth Analg 1998 87:98
NSAID
side effects

GI ulceration
 mild platelet dysfunction
 inhibition bone fusion
 mild Na+ retention / hypertension
  renal function in low flow states
NSAID
side effects
CAN WE MAKE A BETTER NSAID?

Keep analgesic potency
 Reduce side effects
NSAID
mechanism of action

inhibits cyclo-oxygenases (COX-1&2)
which convert arachidonic acid to
prostaglandins (PG)
 
PGE2 to sensitize nociceptors
 
PGE2, PGI2, TXA2 for homeostasis
COX
2 isoforms

COX-1
constitutive – everywhere
‘housekeeping’
PGE2, PGI2, TXA2

COX-2
constitutive in kidney, CNS
induced by trauma / pain
main source PGE2 for sens.
PGE2
production
EP
receptor
BK
receptor
Tissue
Injury
Peripheral induction of COX-2
IL-1
Central induction of COX-2
PGE2
sensitization
PGE2
EP
receptor
Bradykinin
BK
receptor
Tissue
Injury
PGE2
Can we make a selective COX-2 inhibitor
with excellent analgesia and less side
effects than a conventional NSAID?
YES
COX-2
COX-1
NSAID
NSAID
Arachidonic
acid
Arachidonic
acid
COX-2
COX-1
PGE2
PGI2
TXA2
COX-2 Inhibitor
Arachidonic
acid
Arachidonic
acid
COX-2 Inhibitor
COX-2 inhibitors

Celecoxib
 Rofecoxib
 Valdecoxib
COXIB
analgesic potency

similar to or more potent than NSAIDs
 valdecoxib 40 mg = ketorolac 30 mg
= 2 percocets!
 24h duration
DANIELS J Am Dent Assoc 2002 133:611 MEHLISCH J Oral Maxillofac Surg 2003
61:1030
COXIB
pre-emptive effect

rofecoxib 50 mg given 1 h pre-incision vs
post  pain  opioid consumption

prevents PGE2 sensitization from upregulated COX-2
REUBEN Anesth Analg 2002 94:55
COXIB
side effects: GI

 incidence ulcers or bleeding compared to
conventional NSAIDs
BOMBARDIER NEJM 2000 343:1520
COXIB
side effects: renal function

COX-2 constitutive in kidney
 same effect as conventional NSAID
 mild Na+ retention, blood pressure 
  renal blood flow in hypovolemia or  CO
Avoid in hypovolemia, CHF, renal dysfunction,
uncontrolled  BP ,DM
BRATER J Pain Symptom Management 2002 23:S15
COXIB
side effects: bone fusion

conventional NSAIDs inhibit bone growth
& fusion
 coxibs do not appear to clinically affect
bone fusion
 rofecoxib/celecoxib vs control vs ketorolac
in spinal fusion patients
9/132 vs 6/90 vs 23/120
GLASSMAN Spine 1998 23:834 REUBEN ASRA Annual mtg 2002 Abstract
PD-16 LEWIS Proc NA Spine mtg 2000 64
COXIB
side effects:allergy

Can use in asthmatics
 May use rofecoxib with caution in ASA
allergy
 Avoid celecoxib/valdecoxib with sulfa
allergy
GLASSER Pharmacotherapy 2003 23:551 STEVENSON J Allergy Clin Immun
2001 108 :47
COXIB
side effects: platelet function

NO effect on platelets
 NO effect on bleeding
 Patients on warfarin may have  INR
(need to adjust dose for cel/rof)
LEESE Am J Emerg Med 2002 20:275
HOMONCIK Clin Exp Rheumatol
2003 21 :229
Summary
COXIBS compared to NSAIDs

more potent analgesic
 longer duration
 pre-emptive effect
 no effect on platelets
 less or no GI S/E
 no effect on bone fusion
avoid opioid
once a day
use pre-op
use pre-op
use in risk
use in ortho
Multimodal Analgesia
Acetaminophen

Central COX 3 inhibitor
  opioid use by 30%
  opioid related side effects
SHUG Anesth Analg 1998
Multimodal Analgesia
Acetaminophen
Avoid with:




hepatic insufficiency
alcoholism
malnutrition
P450 inducers
Multimodal Analgesia
Acetaminophen + NSAID

usual adjunct for PCA opioid
 combination better than either alone
 VAS  rest & dynamic
FLETCHER Can J Anesth 1997 44:479
Multimodal Analgesia
Local anesthetic

Infiltration
 Intraperitoneal
 Nerve block
 Neuraxial
Local anesthetic

Movement assoc pain
reduces function

Local anesthetic
blocks A & c fibres
Incisional local infiltration
Lap chole 157 pts


periportal & intraperitoneal bupivacaine
pre-incision or at end
 pain first three hours with pre-incisional
periportal bupivacaine (+/- intraperitoneal)
LEE Can J Anesth 2001 48:545
Peritoneal local infiltration
Appendectomy Peritoneal infiltration 0.5% bupivacaine
 pain scores
  analgesic consumption

COLBERT Can J Anesth 1998 45:734
Local infiltration

Bupivacaine
is
BACTERICIDAL
AYDIN Eur J Anesth 2001 18:687
Nerve Block
Single shot
ankle block
interscalene

0.5% bupivacaine
 6-24h postop analgesia
Nerve Block
Continuous
Continuous Femoral Nerve Blk
post total knee arthroplasty
compared to
PCA or epidural
Nerve Block
Continuous femoral

Better analgesia
 Less morphine use
 Less opioid related side effects
 Better ambulation & hemodynamic stability
CAPDEVILLA Anesthesiol 1999 91:8 SINGELYN Anesth Analg 1998 87:88
CHELLY J Arthroplasty 2001 16:436
Nerve Block
Continuous femoral
Better surgical outcome

Less perioperative bleeding
 Increased flexion with CPM
 Earlier hospital discharge
 Less time in rehabilitation
CAPDEVILLA Anesthesiol 1999 91:8 SINGELYN Anesth Analg 1998 87:88
CHELLY J Arthroplasty 2001 16:436
Nerve Block
Single shot femoral
40 ml 0.25% bupivacaine vs saline post TKA





 pain VAS  1-2
50%  morphine use
50%  morphine related side effects
Better ambulation
LOS 3 vs 4 days
WANG
Reg Anesth Pain Med 2002 27:139
Nerve Block
Continuous interscalene /popliteal

Disposable pumps
 Major shoulder /leg
surgery can be done as
an outpatient
 $
Nerve Block
Continuous popliteal nerve block at home

30 pts randomized to
local anesthetic or saline
 Rescue oral opioids
 VRS 0 vs 4/10
 Sleep disturbances 10x
less
 O opioid pills vs 8
ILFIELD Anesthesiology 2002 97:208
Epidural Analgesia
Epidural Analgesia
LOCAL /OPIOID

superior analgesia
 better
cardiopulmonary
function
 earlier return bowel
function
Epidural Analgesia
LOCAL /OPIOID

better ambulation
 decreased hospital stay
 safe to use on wards
Epidural Analgesia
Sigmoidectomy

Early ambulation & feeding
 2 day median hospital stay
KEHLET Br J Surg 1999 86:227
Summary

Pre-op Coxib
 Local infiltration / block
 Acetaminophen / Coxib post-op
 Controlled release opioid
 Thoracic epidural for major abdominal &
thoracic surgery
 Continuous nerve blocks for extremity
surgery