Postoperative Pain Management in Adults Anil Gupta MD, FRCA, PhD Associate Professor, University Hospital, Örebro and Senior Lecturer, University Hospital, Linköping, Sweden

Scandinavia (Norway, Sweden, Denmark) Sweden – 9 million people Oslo, Norway Heart of Scandinavia City of Örebro Population: 125,000 Stockholm, Sweden Copenhagen, Denmark

University Hospital, Örebro, Sweden

Multiple Pain Sites and Pain Mechanisms The intensity of perceived pain is related to: *the type of surgery *the intensity of trauma *previous exposure of pain *sex *age *degree of psycho-social preparation prior to the procedure.

Multiple pain sites requires Multimodal analgesia: Paracetamol + Rofecoxib + dexamethasone or palcebo

Assessment of Pain  

Visual analogue pain scale (VAS) Worst

No pain imaginable pain

 

Numeric Rating Scale/Verbal Rating Score (NRS/ VRS) 0 1 2 3 4 5 6 7 8 9 10

 

Mild pain

Moderate pain

Severe pain

Pain is a subjective experience and cannot always be measured

Can pain intensity be predicted?

Predictors of Postoperative Pain

APAIS: Amsterdam Preoperative Anxiety and Information Scale

Incidence of Pain % of patients with Moderate – Severe Pain 30% patients had moderatesevere pain Neurosurgery General surgery Orthopedic surgery Hand surgery Plastic surgery McGrath et al. Can J Anesth 2004

Postoperative Pain Pain as a factor complicating recovery and discharge after ambulatory surgery

Painful Procedures: Inguinal Herniorrhaphy Laparoscopic Surgery Plastic Surgery

Pavlin et al, Anesth Analg 2002

Anesthesiology 2002

Overall incidence (95% CI) of post-discharge pain was 45% (6 – 95%)

Management Principles   ’Preventive’  

management

Prevent pain by reducing nociceptive input

  ’Pro-active’

management

’Treat’ the patient ”even if they have no pain”   Give drugs regularly ”irrespective” of pain intensity  

  ’Multi-modal’  

management

Use different drugs with different mechanisms of action

Preventing Pain

Curr Opin Anesth 2006

Preventive Analgesia  

An appropriate postoperative pain treatment:        

 

may start before surgery last long enough after surgery avoid pain-induced sensitization processes includes effective analgesic interventions

The concept of preventive analgesia includes:      

Multimodal anti-nociceptive techniques with analgesics Exceed the expected duration of action of these drugs Attenuates peripheral or central hypersensitivity

Preventive Analgesia   Includes

(but is not limited to) the use of:

Local anesthetics   Paracetamol   NSAID’s   Opioids   Others e.g. Gabapentin, pregabalin, ketamine etc.  

Single or combination of drugs where the duration of effect exceeds the duration of pharmacological analgesia of each drug

Treating Pain  Pharmacological

methods

Local anesthetics

 

Paracetamol

 

Non-steroidal anti-inflammatory drugs  

Opioids and related drugs

 

Other drugs

 

 Non-pharmacological

methods

Cold compresses

 

TENS, music, acupuncture etc.

 

Local Anesthetics   Advantages

Rapid onset of action   Low risk of toxicity   Excellent analgesia   Cheap  

  Disadvantages

Short duration of action when injected locally   Can cause ’hyperalgesia’ when effect wears off  

Local Anesthetics   Prolonging

effect duration

Use long-acting LA   Use nerve blocks instead of infiltration   Combine with adjuvants (clonidine, morphine)   Use catheters to inject LA intermittently   Microsomal-bound LA (still experimental)  

LA provide excellent pain relief, but of short duration

Procedure-specific Pain Management http://www.postoppain.org/

Because of the varying pain intensity following different types of surgery, a procedure specific pain management approach should be used.

Knee Arthroscopy Options: Femoral nerve block Intraarticular analgesia • Morphine • LA • NSAID Oral analgesics

Knee Arthroscopy I/A Local anesthetics

Conclusion: Weak evidence of mild reduction in postoperative pain of short duration Moiniche et al. 1999

Knee Arthroscopy I/A Morphine          

Mild effect when injected intraarticularly Duration up to 24 h postoperatively Effect is best when pain is moderate-severe Dose of 5 mg is optimal Systemic effect of 5 mg morphine i.a. in the early period cannot be excluded

Intraarticular analgesia: Combination of LA with morphine and NSAID are efficacious

Local Infiltration Analgesia (LIA)

Knee Surgery Local Infiltration Analgesia (LIA)

LIA: Ropivacaine + ketorolac + adrenaline infiltration in and around the knee (Group A) Median postoperative hospital stay was less in group A (n = 19) than in group P (n = 19): 1 (1–6) days vs. 3 (1–6) days (p < 0.001).

Acta Orth Scand 2009

Shoulder surgery Options Paravertebral block Interscalene Block Supraclavicular block Intraarticular analgesia

Unilateral shoulder arthroscopy All patients received an interscalene block M-IR: I/A ropivacaine 2 ml/h 48 h M-IS: I/A saline 2 ml/h

Prospective, double blind study

Lower pain intensity using I/A ropivacaine compared to saline

Suprascapular block (SSB): 10 ml bupivacaine 0.25% + adr. Intra-articular analgesia (IA): 20 ml bupivacaine 0.25% + adr. Interscalene block (ISB): 20 ml bupivacaine 0.25% + adr.

Interscalene block provides best analgesia. When contraindicated, supra-scapular block is preferable.

Herniorrhaphy

Options  Local

anesthetic infusion  Spinal anesthesia  Ilio-inguinal nerve block  Multimodal management

Spinal Anesthesia Spinal anesthesia: Bupivacaine 6 mg or 7.5 mg (+ fentanyl 25 µg)

Conclusion: VAS < 4 up to 7 days postoperatively ? Preventive effect ? Gupta et al, Acta Anesth Scand 2003

Laparoscopic surgery Options Intraperitoneal LA Multimodal analgesia Intercostal nerve block

. Pain on Coughing

Conclusion Pain was mild even in the placebo group during 0 – 7 days VAS = 3

Gupta et al A & A 2002

Breast surgery Options Paravertebral block Infiltration analgesia +/- catheters Oral analgesics

Breast Augmentation Surgery

Pain at rest (0-24 t) VAS 3 - 6

Pain after infusion of 10 ml LA

Rawal et al, EJA 2006

Analgesics in Day Surgery

NSAID  Systemic

administration

 Intravenous  Oral  Rectal

 Local

Injection

 Intra-articular  IVRA  Sub-cutaneous

NSAID  

Advantages    

 

Moderately long effect-duration Effective when used in combination with other drugs

Disadvantages    

Not tolerated by all patients (allergy etc) Risk of perioperative bleeding is a cause for concern by some surgeons

NSAIDs are efficacious in the presence of moderate pain during day surgery

NSAID – summary   Ketorolac

has been found to be efficacious:

When used in a dose of 60 mg during IVRA   When used for wound infiltration   When injected intraarticularly   When combined with other drugs  

Concerns remain about the effects of ketorolac on bone-healing

Paracetamol Tablet * satisfactory absorption

Suppository * poor absorption Intravenous (Perfalgan) *Rapid effect (< 15 min)

Therapeutic concentration

IV paracetamol or 2 g oral Conclusion:

For rapid onset of effect, use iv paracetamol (Perfalgan®) As ’premedication’, use 2 g paracetamol for best effect. Rectal route should be abandoned! Holmér Pettersson et al. Acta 2006

Clonidine Efficacy documented following Intravenous injection Intraarticular injection Spinal injection Following IVRA

Conclusions: Clonidine 1 µg/kg (IVRA) results in: 1.  Improved analgesia in PACU during first 2 h postoperatively 2.  Decreased need for analgesic supplements 3.  Well tolerated by patients

Drug Combinations

R: Ropivacaine M: Morphine K: Ketorolac

Decreased morphine consumption in RMK group compared to Group RM or Placebo Anesth & Analg 2006

Non-pharmacological Methods   Music

Day surgery (183 patients): Some beneficial effect of music on postoperative pain. In general, pain scores were low!

Acta Anesth Scand 2003

Non-pharmacological Methods   Acupuncture

Acupuncture

Intradermal acupuncture: 1.  Reduced incisional and visceral pain 2.  Reduced analgesic requirements 3.  Diminished PONV Easy to use and safe; few side effects Anesthesiology 2001

Post-discharge Pain Relief   Based

upon

Tablets (Paracetamol, NSAID etc)   LA via catheters   Cold compresses   Music   Wait, watch, hope, pray …………..  

Better methods for pain management at home are urgently needed!

The Future   Procedure-specific

pain management

Newer drugs   Newer delivery systems  

  Patient-specific

pain management

Better understanding of the genetic code   Pain mapping  

  Surgeon-specific  

pain management

Why some surgeons cause more pain than others!!!!!

Conclusions   Effective

pain management requires a procedure-specific approach   Pain is a consequence of surgery and should be anticipated, prevented and treated quickly   Poorly treated postoperative pain can lead to chronic pain syndromes   Multimodal approach to pain management should be a routine in day surgery

Thank you for your attention