DISCLOSURE

1
DISCLOSURE

• MEMBER OF MEDICAL ADVISORY BOARD
  PFIZER-LYRICA(PREGABILIN)

2
ASSESSMENT AND MANAGEMENT OF REFRACTORY POST-OP
PAIN

• R.HEWKO MD FRCPC

3
SIGNIFICANCE

• PATIENT PERSISTANT DISTRESS
• INABILITY TO MOBILIZE
• PROLONGED
  HOSPITALIZATION
• POTENTIAL FOR
  IATROGENISIS
• EVOLUTION OF CHRONIC
  PAIN
• SYSTEM RESOURCE UTILIZATION
• PHYSICIAN ETHICAL OBLIGATION
• MEDICAL/LEGAL
  CONSEQUENCES

4
DIFFERENTIAL DIAGNOSIS

• EVOLVING PROCESS
• NARCOTIC DEPENDANCY
• NARCOTIC TOLERANCE
• LOW PAIN TOLERANCE
• NEUROPATHIC PAIN
• MALINGERING

5
EVOLVING PROCESS

• AT RISK
• complex trauma patients
• long bone s-compartment syndrome
• ASSESSMENT
• Hx- quality, pattern of pain
• Further investigation

6
NARCOTIC DEPENDENCY VS NARCOTIC TOLERANCE

• NARCOTIC TOLERANCE DEFN.
• PHYSIOLOGICAL STATE RESULTING IN INCREASED
  DOSE OF NARCOTIC TO OBTAIN SIGNIFICANT EFFECT.
• ABRUPT DISCONTINUATION MAY RESULT IN
  PHYSICAL WITHDRAWAL SYMPTOMS
• NARCOTIC DEPENDANCY DEFN.
• INNAPPROPTIATE / EXCESSIVE USE OF NARCOTIC
  FOR NON-MEDICALLY INDICATED REASONS
• MAY OR MAY NOT BE ASSOCIATED WITH
  WITHDRAWAL WITH ABRUPT DISCONTINUATION

7
ASSSESSMENT OF DEPENDENCY

• AGENT(S)
• AMOUNT
• DURATION
• LAST USE
• PREVIOUS WITHDRAWAL
• WITHDRAWAL MANAGEMENT

8
PAIN MANAGEMENT

• EQUIVALENCY
• MORPHINE / HEROIN-ALMOST EQUAL IN
  MOLECULAR WEIGHT / POTENCY
• PURITY OF HEROIN 15 TO 85
• RELIABILITY
• ALCOHOLICS REPORT HOW LITTLE THEY DRINK
• HEROIN ADDICTS REPORT HOW MUCH THEY USE
• IATROGENISIS
• SIG. POTENTIAL FOR OVERDOSE

9
RX OPTIONS

• AGENTS -MORPHINE
• DEMEROL- MORPHINE ALLERGY?
• METHADONE -ONLY IF DOCUMENTED USE
  
• OR FOR
  STABILIZATION
• - MAINTAIN IF
  POSSIBLE
• - 1mg methadone 4-10mg
  morphine
• OPTIONS-CONTINUOUS INFUSION
• PRN PO/SC/IM/IV
• CONTIN

10
MANAGEMENT

• ESTABLISH TOLERANCE
• IV BOLUS 2-4 MG DOSES
• ASSESS FOR RESPONSE-DEGREE OF ANALGESIA /
  LOC
• TITRATION
• AGGRESSIVE PRNS 10-20 MG SC/IM OR 20-30 MG
  PO Q3H
• 1-5 MG
  IV BOLUS QIH
• CONTINUOUS INFUSION-RANGE 4-10 MG TITRATE
• TRANSITION TO CONTIN WITH PRNS
• EQUIVALENCY
• PARENTERAL TO ORAL -1 mg PARENTERAL TO 2
  ORAL

11
NARCOTIC TOLERANCE

• BASE REG.DOSE PLUS REG PRNS
• CONTIN OR CONT. INFUSION
• - maintain methadone/fentanyl patch
• PRNS - 1 ½ TO 2 X STANDARD
• KETAMINE / EPIDURALS
• TITRATE BASE Anticipate escalating base
  requirement.

12
NARCOTIC INSENSITIVITY ?

• PROFILE- long term use very large doses of
  regular narcotics
• - minimal response to large
  doses prn narcotics
• MECHANISM- physiologic upregulation
• MANAGEMENT - KETAMINE
• - NMDA ANTAGONIST
• -RESET SYSTEM

13
LOW PAIN TOLERANCE

• PAIN TOLERANCE
• PHYSIOLOGICAL VARIABLITY
• NARCOTIC TOLERANCE-endogenous endorphin
  suppression
• PSYCHOLOGICAL VARIABILITY
• PERSONALITY
• DRUG DEPENDANCY-NARCOTIC/OTHER
• EXPECTATIONS-COMPLETE PAIN RELIEF
• ALL OR NONE (0 1 10 PAIN SCALE)
• CHRONIC PAIN-PHYSIOLOGICAL/PSYCHOLOGICAL
  FACTORS
• MANAGEMENT EXPECTATIONS / POLYPHARMACY

14
REFRACTORY PAIN- PSYCHOTHERAPY

• PATIENT POPULATION
• NARCOTIC TOLERANT/DEPENDANT
• LOW PAIN TOLERANCE
• 
  
  
• DISCUSSION CLARIFY EXPECTATIONS
  
• 
  LIMITS OF MANAGMENT
  
• 
  LIMITS OF NARCOTICS
• RISKS
  OF XS NARCOTIC
  
  

15
REFRACTORY PAIN - PHARMACOTHERAPY

• PHARMACOTHERAPY
• EPIDURALS / KETAMINE
• ESP WITH NARCOTIC TOLERANCE
• TYELENOL STANDARD
• BENZODIAZEPINES
• ANXIOLYTIC BUT
• RISK OF DISINHIBITION/INTOXICATION
• - RESPIRATORY COMPROMISE

16
REFRACTORY PAIN-PHARMACOTHERAPY

• NOZINAN (METHOTRIMEPRAZINE)
• LOW POTENCY NEUROLEPTIC
• MINIMAL RISK OF EPS / DYSTONIA
• ANXIOLYTIC
• ANALGESIC
• SEDATIVE WITHOUT RISK OF RESPIRATORY
  COMPROMISE
• POTENTIATION OF NARCOTIC
• DOSING ANALGESIC 2.5-5mg Q3H PRN
• 
  5 TO 10 mg TID
  
• SEDATION 10 - 20 mg
  / 25 - 50 mg QHS PRN/REG

17
NEUROPATHIC PAIN

• HX / EVIDENCE NERVE INJURY
• overt - amputations 80 acute
• covert - any large incision
• LIMITED RESPONSE TO NARCOTICS
• QUALITY- DYSESTHESIA
• HYPERASTHESIA
• ALLODYNIA
• LANCINATING
  

18
NEUROPATHIC PAIN - MANAGEMENT

• NARCOTICS-may require pre-anesthetic doses/rapid
  development tolerance
• GABAPENTIN / PREGABALIN
• Dose range- Gabapentin 100mg tid to 1200mg
  qid
• - Pregabalin
  75mg bid to 300mg bid
  
• TCAS NORTRIPTYLINE/DESIPRAMINE
• Dose range 10 mg bid to 25 mg tid
• BEST OPTION TCA PLUS GABAPENTIN/PREGABALIN

19
MALINGERING

• ASSESSMENT
• OBSERVATION-OVERT/COVERT
• NURSING NOTES
• MANAGEMENT
• CONFRONTATION
• LIMITS
• EXPECTATIONS
• CONSEQUENCES

20
SUMMARY

• ETHICAL / MED-LEGAL OBLIGATIONS
• ONGOING ASSESSMENT/ TITRATION
• CLARIFY EXPECTATIONS / GOALS
• MAINTAIN DIFFERENTIAL
• RECOGNITION OF LAYERS
• PHARM ADJUVANTS
• NEED FOR OUT PATIENT SERVICES