OPTIMIZING ACUTE PAIN MANAGEMENT
From the 60th Postgraduate Assembly in Anesthesiology, presented by the New York State Society of
Anesthesiologists
| ACETAMINOPHEN AND NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS): SHOULD I USE
THEM?—Scott S. Reuben, MD, Professor of Anesthesiology and Pain Medicine, Tufts University School of Medicine,
Boston, MA, and Director, Acute Pain Service, Baystate Medical Center, Springfield, MA
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| Introduction: increasing number of outpatient procedures necessitated new approaches to pain management; 1992
guidelines from Agency for Health Care Policy and Research (AHCPR; now Agency for Healthcare Research and
Quality) recommended multimodal pain management; Warfield study of 500 hospitals in United States found 80%
of patients complained of moderate-to-extreme pain after surgery; American Society of Anesthesiologists (ASA)
and American Pain Society (APS) also published guidelines on pain management; Apfelbaum study found pain
continues to be undermanaged; incidence of extreme pain doubled in past 10 yr; top 5 patient concerns before
surgery—5) treatment by clinician, 4) pain during surgery, 3) full recovery from surgery, 2) improvement in condition
following surgery, and 1) pain after surgery
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| Barriers to pain treatment: inadequate education on pain management; outdated ideas about how nervous system
functions (eg, specificity theory, gate-control theory)
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| Preventive analgesia: multimodal analgesics recommended preoperatively and postoperatively; A delta (Adelta) and
C fibers carry pain; A β fibers carry innocuous sensations; pathologic pain occurs during surgery; Adelta and C fibers
become sensitized, lowering pain threshold at site of injury and resulting in persistent pathologic pain; controlling
inflammatory mediators peripherally and centrally important for pain management
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| Nonsteroidal anti-inflammatory drugs (NSAIDs): reduce analgesic use and improve analgesic duration; particularly
effective in reducing movement-related pain (opioids ineffective); block transduction and peripheral pain
pathways; some NSAIDs block central sensitization; associated with increased incidence of perioperative bleeding
when administered before surgery (especially total joint surgery); have anti-inflammatory and analgesic effects
(block dull diffuse pain associated with C fibers, but not sharp stabbing pain associated with Adelta fibers); ceiling
effect—all have maximum effective dose; no additional analgesia, but increased side effects; mode of action—all
except aspirin reversibly inactivate cyclooxygenase (COX); prostaglandin E (PGE) formation (inhibited by
NSAIDs) lowers pain threshold at site of injury (primary hyperalgesia), resulting in peripheral sensitization, and
eventually, central sensitization
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| ASA guidelines: multimodal pain management indicated whenever possible; unless contraindicated, every patient
should receive around-the-clock NSAIDs, COX-2 inhibitors (coxibs), and/or acetaminophen
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| Analgesic efficacy: number needed to treat (NNT) to reduce pain by ≥50% in 1 patient (lower number indicates
more effective treatment); NSAIDs have NNT of 1.5 to 2; opioids have NNT of ≈3; codeine has NNT of ≈17
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| Acetaminophen: primarily blocks central synthesis of prostaglandins; used in addition to standard NSAIDs (may
work synergistically); may affect serotonergic mechanisms; associated with limited opioid-sparing effect (10% to
30%); available in intravenous (IV) formulation (para-cetamol) in United Kingdom; may inhibit activity (centrally)
of COX-3; associated with morphine-sparing effect of ≈20% (not associated with decrease in morphine-related adverse
effects); combinations—used in conjunction with NSAIDs and COX-2 inhibitors
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| Traditional NSAIDs: reversible blockers of COX; agents should be discontinued in time to allow for elimination (2
days sufficient for most drugs); ketorolac—contraindicated for preemptive use; small dose given at site of injury
(eg, surgical incision) more effective than IV, intramuscular (IM), or oral (PO) administration and associated with
fewer systemic side effects
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| Pain pathways: central—neural transduction, blocked by, eg, spinal anesthesia; peripheral—humoral pathway
involving cytokines also results in COX-2 upregulation
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| COX-2 inhibitors: unlike ketorolac, centrally acting COX-2 inhibitors cross blood-brain barrier to eradicate PGE2
in central nervous system (CNS); preoperative administration not associated increased blood loss, compared to
placebo; celecoxib approved for acute pain; recommended dose, 400 mg, followed by 200 mg 12 hr later; this
dosing regimen results in ≈30% reduction in opioid use; postoperative healing—studies indicate impairment of
spinal fusion, but dose and duration important; deleterious effects of COX-2 inhibitors on spinal fusion avoidable
with low-dose short-term treatment
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 | Prevention of chronic pain: study—patients administered celecoxib (400 mg loading dose, followed by 200 mg
q12h for 5 days) reported significantly lower incidence of chronic pain after surgery, compared to patients in placebo
group; proposed mechanisms—COX-2 inhibitors may prevent peripheral and central sensitization, and
therefore prevent chronic pain; spinal prostaglandins have role in development, but not maintenance, of chronic
pain; by preventing upregulation of COX-2 expression (involved in prostaglandin-dependent allodynia) after
surgery, COX-2 inhibitors may prevent neuropathic pain postoperatively
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| Meta-analysis: NSAIDs, COX-2 inhibitors, and acetaminophen associated with morphine-sparing effect (15% to
55%); NSAIDs—decrease pain intensity at 24 hr; reduce incidence of nausea and vomiting; associated with less
sedation; associated with risk for bleeding
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| Multimodal therapy: gabapentin (Pregabalin) works synergistically with NSAIDs in animal model; in humans,
combination of celecoxib and gabapentin following spinal fusion surgery results in ≈80% reduction in opioid use
and opioid-related side effects; combination also reduces pain with movement (more effective than single agents);
example—acetaminophen and celecoxib used before gabapentin; patients taking oxycodone (eg, OxyContin) preoperatively
should continue taking it on day of surgery; methadone (N-methyl-D-aspartate acid [NMDA]-receptor
antagonist) used intraoperatively; ketamine, 0.3 mg/kg; bupivacaine (Marcaine), clonidine, and morphine used to
infiltrate surgical site; acetaminophen, celecoxib, pregabalin, and oxycodone given postoperatively
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| Total knee replacement: naproxen (Naprosyn), 500 mg bid (stop ≈2 days before surgery); but, stopping NSAID
may result in osteoarthritic flare; preoperative pain best predictor of postoperative pain and other measures of patient
outcome (including complications, eg, complex regional pain syndrome [CRPS]) after total joint replacement
(ie, controlling preoperative pain important for outcome); COX-2 inhibitors—perioperative use decreases
pain with movement; use in multimodal setting reduces opioid use, improves pain relief, reduces vomiting, improves
sleep disturbance, improves range of motion, and increases patient satisfaction
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| Example of multimodal approach: discontinue NSAIDs 2 to 3 days before surgery; give 1 g acetaminophen, 400
mg celecoxib, and pregabalin perioperatively; consider combined spinal-epidural technique intraoperatively;
consider patient-controlled epidural analgesia (PCEA) postoperatively; provide celecoxib, acetaminophen, pregabalin,
and oxycodone, 10 mg every 12 hr; also consider ice, cryotherapy, and oral multimodal analgesics
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| Anterior cruciate ligament (ACL) repair: acetaminophen and rofecoxib given preemptively (2 days before
surgery); femoral nerve block; intra-articular bupivacaine, clonidine, and morphine; no opioids intraoperatively
(induces nausea and vomiting, sedation, and prolonged hospital stay); postoperatively, cryotherapy, acetaminophen,
rofecoxib, and controlled-release oxycodone; combined with rehabilitation protocol (weight-bearing
within first day of surgery; full knee extension within 48 hr; full sports activity within 6 mo); multimodal approach
and aggressive physical therapy improves pain scores, reduces opioid use, improves side effects, decreases time
spent in hospital, and improves long-term outcomes (eg, rates of reoperation, CRPS, and complications)
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| USING REGIONAL TECHNIQUES AS MULTIMODAL PAIN THERAPY—Paul H. Willoughby, MD, Associate
Professor of Anesthesiology, and Director, Acute Pain Service, State University of New York Health Sciences Center at
Stony Brook, NY
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| Advantages of regional anesthesia: increased patient comfort; reduced narcotic use (less nausea and vomiting;
less sedation); faster discharge times; greater patient satisfaction; part of balanced approach to anesthesia and postoperative
analgesia, but used relatively infrequently
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| Problems using regional anesthesia and analgesia: requires additional training; prolongs start time (if performed
in operating room [OR]); requires additional equipment; may create conflict within anesthesia department
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| Incidence: ≈1% of all anesthesia residents in United States participate in regional anesthesia fellowships; 61% of
those return to academics; majority of academic departments in United States need more regional anesthesiologists;
most anesthesiologists uncomfortable performing regional anesthesia procedures; number of blocks performed during
residency inadequate “to make someone a master”
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| Changing routines in hospital: define scope of practice and future goals; assess current situation and flow of patient
care; identify type of equipment available, facilities, staffing, and policies; identify predominant culture (eg,
desire to improve pain management); develop treatment plans
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| Barriers: patients and families—often have misconceptions (need to educate); hospital personnel—nurses and
support personnel must be educated; surgeons “sometimes a barrier”; fellow anesthesiologists usually biggest barrier
to getting regional anesthesia integrated into patient care
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| Small-team approach: small group of regional anesthesiologists places blocks and integrates coverage afterwards;
identified individuals responsible for specialty call, compensation issues, staffing, and hospital support; 1 or
2 (preferred) regional anesthesiologists needed for single-shot blocks and to integrate regional anesthesia into postoperative
pain management; catheters require larger number of anesthesiologists for placement and follow-up care;
team also may be involved with patient-controlled analgesia (PCA) and consultations (not always possible in private
practice); tips for improved outcome—talk to patient before procedure (eg, during preadmission testing; surgeons
and nurses useful for educating patients); ensure skilled personnel available; if using designated block area
apart from OR, get patient there early; train OR personnel in management of regional anesthesia and analgesia; onset
of action—affected by volume, concentration, and time; efficiency—total time in OR reduced by 15 to 30 min
when patient receives block before arrival at OR; use of ultrasonography improves timing and success rates
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| Integration of regional anesthesia into practice: reduces need for narcotics; multimodal approach to pain management
still necessary; catheter management—specialized team improves efficiency of placing catheters; peripheral
nerve catheters and blocks require less management by other personnel; follow-up necessary (visit or call
patient); if catheter present, staffing must be available to evaluate (eg, to manage disconnections and other problems);
speaker’s institution teaches floor management for clinical anesthesia-1 (CA-1; first year) residents; procedure
form necessary to integrate regional anesthesia into postoperative pain management (billing requires referring
physician’s signature); acceptable to supervise 3 blocks at same time (but anesthetic cannot be done simultaneously);
documentation—ask for request for consultation; document presence during procedure; complications—study of
620 outpatients with peripheral nerve catheters (interscalene, popliteal, or femoral) found most problems occur in interscalene
catheters (tend to leak and fall out frequently); nerve damage rare; consent—may be necessary to obtain
consent and mark patient before going to OR; on consent forms, document correct side for surgery; have patient,
physician, and nurse read and confirm “that everything is appropriate”; coordination—small-team approach may
require anesthesia provider to “run around” from one case to another
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| Ultrasonography: makes regional anesthesia easier; increases speed, particularly in novices; easier to teach than
neurostimulation; lowers number of blocks necessary to learn particular technique; may prevent nerve injury;
billable; offers regional anesthesia and analgesia to patients not normally eligible
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| Hospital politics: “guard your reputation with your life”; make people come to you for regional anesthesia; remember
that action, not argument, produces results; appeal to self interest (eg, shorter cases; improved patient comfort;
improved discharge times); affect hearts and minds of others (eg, appeal to nurses as advocates for patient
care and comfort); learn to make others dependent on you; avoid becoming an “isolated fortress”; be patient (correct
integration requires complete planning and implementation)
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Suggested Reading
Apfelbaum JL et al: Postoperative pain experience: results from a national survey suggest postoperative pain continues
to be undermanaged. Anesth Analg 97:534, 2003; Armstrong KP, Cherry RA: Brachial plexus anesthesia
compared to general anesthesia when a block room is available. Can J Anaesth 51:41, 2004; Block BM et al: Efficacy
of postoperative epidural analgesia: a meta-analysis. JAMA 290:2455, 2003; Elia N et al: Does multimodal analgesia
with acetaminophen, nonsteroidal antiinflammatory drugs, or selective cyclooxygenase-2 inhibitors and patient-controlled
analgesia morphine offer advantages over morphine alone? Meta-analyses of randomized trials. Anesthesiology
103:1296, 2005; Gilron I et al: Cyclooxygenase-2 inhibitors in postoperative pain management: current evidence and
future directions. Anesthesiology 99:1198, 2003; Hargett MJ et al: Guidelines for regional anesthesia fellowship
training. Reg Anesth Pain Med 30:218, 2005; Joshi W et al: An evaluation of the safety and efficacy of administering
rofecoxib for postoperative pain management. Anesth Analg 97:35, 2003; Nussmeier NA et al: Safety and efficacy
of the cyclooxygenase-2 inhibitors parecoxib and valdecoxib after noncardiac surgery. Anesthesiology 104:518, 2006;
Remy C et al: Effects of acetaminophen on morphine side-effects and consumption after major surgery: meta-analysis
of randomized controlled trials. Br J Anaesth 94:505, 2005; Reuben SS et al: Evaluating the analgesic efficacy of administering
celecoxib as a component of multimodal analgesia for outpatient anterior cruciate ligament reconstruction
surgery. Anesth Analg 105:222, 2007; Reuben SS et al: The effect of cyclooxygenase-2 inhibition on acute and
chronic donor-site pain after spinal-fusion surgery. Reg Anesth Pain Med 31:6, 2006; Reuben SS et al: The effect of
initiating a preventive multimodal analgesic regimen on long-term patient outcomes for outpatient anterior cruciate ligament
reconstruction surgery. Anesth Analg 105:228, 2007; Romsing J, Moiniche S: A systematic review of COX-2
inhibitors compared with traditional NSAIDs, or different COX-2 inhibitors for post-operative pain. Acta Anaesthesiol
Scand 48:525, 2004; Steele SM et al: Epidural anesthesia and analgesia: implications for perioperative coagulability.
Anesth Analg 73:683, 1991; Viscusi ER et al: Forty-eight hours of postoperative pain relief after total hip arthroplasty
with a novel, extended-release epidural morphine formulation. Anesthesiology 102:1014, 2005; Warfield CA, Kahn
CH: Acute pain management. Programs in U.S. hospitals and experiences and attitudes among U.S. adults. Anesthesiology
83:1090, 1995; White PF: The role of non-opioid analgesic techniques in the management of pain after ambulatory
surgery. Anesth Analg 94:577, 2002.
Educational Objectives
| The goal of this program is to improve management of acute pain by emphasizing the importance of using acetaminophen
and nonsteroidal anti-inflammatory drugs, and through the use of regional techniques as multimodal therapy.
After hearing and assimilating this program, the participant will be better able to:
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| Identify the barriers to good pain treatment.
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| List the analgesic properties of traditional nonsteroidal anti-inflammatory drugs (NSAIDs).
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| Describe the analgesic properties of acetaminophen, cyclooxygenase-2 (COX-2) inhibitors, and traditional
NSAIDs.
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| Indicate the advantages and disadvantages of using regional techniques as part of a multimodal approach to
pain therapy.
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| Explain the integration of regional techniques for pain management into an anesthesia practice.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose
relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any
identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary
business or commercial interest. For this program, the faculty reported nothing to disclose.
Acknowledgements
Drs. Reuben and Willoughby spoke at the 60th Postgraduate Assembly in Anesthesiology, held February 8-12, 2006,
in New York, NY, and sponsored by the New York State Society of Anesthesiologists, Inc. The Audio-Digest Foundation
thanks the speakers and the NYSSA for their cooperation in the production of this program.
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