1. Lecture Title: Acute Pain Management
بسم الله الرحمن الرحيم
Lecture Title: Acute Pain Management
Lecturer name:
Lecture date:

2. Lecture Objectives..
Students at the end of the lecture will be able to:
Learn a common approach to emergency medical problems encountered in the postoperative period.
Study post-operative respiratory and hemodynamic problems and understand how to manage these problems.
Learn about the predisposing factors, differential diagnosis and management of PONV.
Understand the causes and treatments of post-operative agitation and delirium.
Learn about the causes of delayed emergence and know how to deal with this problem.
Learn about different approaches of post-Operative pain management

3. Postoperative care - Post Anesthesia Care Unit “PACU”

4. PACU Design should match function Location: Monitoring equipment
Close to the OR.
Access to x-ray, blood bank & clinical labs.
Monitoring equipment
Emergency equipment
Personnel

5. Admission to PACU Steps: Coordinate prior to arrival, Assess airway,
Administer oxygen,
Apply monitors,
Obtain vital signs,
Receive report from anesthesia personnel.

6. PACU - ASA Standards Standard I Standard II Standard III Standard IV
All patients should receive appropriate care
Standard II
All patients will be accompanied by one of anesthesia team
Standard III
The patient will be reevaluated & report given to the nurse
Standard IV
The patient shall be continually monitored in the PACU
Standard V
A physician will signing for the patient out of the PACU

7. Patient Care in the PACU
Admission
Apply oxygen and monitor
Receive report
Monitor & Observe & Manage
 To Achieve
Cardiovascular stability
Respiratory stability
Pain control
Discharge from PACU

8. Monitoring in the PACU Baseline vital signs. Respiration Circulation
RR/min, Rythm
Pulse oximetry
Circulation
PR/min & Blood pressure
ECG
Level of consciousness
Pain scores

9. Initial Assessment Color Respiration Circulation Consciousness
Activity

10. Aldrete Score 2 1 Score Activity Respiration Circulation
Consciousness
Oxygen Saturation 2
Moves all extremities
Breaths deeply and coughs freely.
BP + 20 mm of preanesth. level
Fully awake
Spo2 > 92%
on room air 1
Moves 2 extremities
Dyspneic, or shallow breathing
BP mm of preanesth. level
Arousable on calling
Spo2 >90%
With suppl. O2
Unable to move
Apneic
BP + 50
mm of preanesth. level
Not responding
Spo2 <92%

11. Common PACU Problems Airway obstruction Hypoxemia Hypoventilation
Hypotension
Hypertension
Cardiac dysrhythmias
Hypothermia
Bleeding
Agitation
Delayed recovery
“PONV”
Pain
Oliguria

12. 1. Airway Obstruction Most common: tongue fall back
 posterior pharynx
May be foreign body
Inadequate relaxant reversal
Residual anesthesia

13. Management of Airway Obstruction
Patient’s stimulation,
Suction,
Oral Airway,
Nasal Airway,
Others:
Tracheal intubation
Cricothyroidotomy
Tracheotomy

14. 2. Hypoventilation Residual anesthesia Post oper - Analgesia Narcotics
Inhalation agent
Muscle Relaxant
Post oper - Analgesia
Intravenous
Epidural

15. Treatment of Hypoventilation
Close observation,
Assess the problem,
Treatment of the cause:
Reverse (or Antidote):
Muscle relaxant  Neostigmine
Opioids  Naloxone
Midazolam  Anexate

16. 3. Hypertension Common causes: e.g. Hypertensive patients
Pain
Full Bladder
Hypertensive patients
Fluid overload
Excessive use of vasopressors

17. Treatment of Hypertension
Effective pain control
Sedation
Anti-hypertensives:
Beta blockers
Alpha blockers
Hydralazine (Apresoline)
Calcium channel blockers

18. 4. Hypotension Decreased venous return Hypovolemia, Sympathectomy,
 fluid intake
 losses
Bleeding
Sympathectomy,
3rd space loss,
Left ventricular dysfunction

19. Treatment of Hypotension
Initially treat with fluid bolus,
+ Vasopressors,
+ Correction of the cause

20. 5. Dysrhythmias Secondary to Hypoxemia Hypercarbia Hypothermia
Acidosis
Catecholamines
Electrolyte abnormalities.

21. Treatment of Dysrhythmia
Identify and treat the cause,
Assure oxygenation,
Pharmacological

22. 6. Urine Output Oliguria Treatment: Hypovolemia, Surgical trauma,
Impaired renal function,
Mechanical blocking of catheter.
Treatment:
Assess catheter patency
Fluid bolus
Diuretics e.g. Lasix

23. 7. Post op Bleeding Causes: Usually Surgical Problem, Coagulopathy,
Drug induced

24. Treatment of Post op Bleeding
Start i.v. lines  push fluids
Blood sample,
CBC,
Cross matching,
Coagulopathy
Notify the surgeon,
Correction of the cause

25. 8. Hypothermia Most of patients will arrive cold Treatment:
Get baseline temperature
Actively rewarm
Administer oxygen if shivering
Take care for:
Pediatric,
Geriatric.

26. 9. Altered Mental Status Reaction to drugs? Pain Full bladder
Drugs e.g. sedatives, anticholinergics
Intoxication / Drug abusers
Pain
Full bladder
Hypoventilation
Low COP
CVA

27. Treatment of Altered Mental Status
Reassurances,
Always protect the patient,
Evaluate the cause,
Treatment of symptoms,
Sedatives / Opioids if necessary.

28. 10. Delayed Recovery Systematic evaluation Pre-op status
Intraoperative events
Ventilation
Response to Stimulation
Cardiovascular status

29. Delayed Recovery The most common cause: Hypothermia,
Residual anesthesia  Consider reversal
Hypothermia,
Metabolic e.g. diabetic coma,
Underlying psychiatric problem
CVA

30. 11. Postoperative Nausea & Vomiting “PONV”
Risk factors
Type & duration of surgery,
Type of anesthesia,
Drugs,
Hormone levels,
Medical problems,
Autonomic involvement.

31. Prevention of PONV NPO status Dexamothasone, Droperidol,
Metoclopramide,
H2 blockers,
Ondansetron,
Acupuncture

32. 12. Postoperative Pain

33. 12. Postoperative Pain Causes: Others:
Incisional Skin and subcutaneous tissue
Laparoscopy Insuflation of Co2
Others:
Deep cutting, coagulation, trauma
Positional nerve compression, traction & bed sore.
IV site needle trauma, extravasation, venous irritation
Tubes drains, nasogastric tube, ETT
Surgical complication of surgery
Others cast, dressing too tight, urinary retention

34. PAIN MEASUREMENTS Subjective Objective
Uni-Dimensional
Multidimentional
Behavioral.
Physiological.
Neuro-endocrinal.
Algometry.
VRS, VAS & NRS.
Facial expression.
McGill P Q,
Pain Inventory.
ACUTE PAIN
Chronic Pain
Both

35. Visual Analogue Scale (VAS) Numeric Rating Scale (NRS)
Pain Scores
Visual Analogue Scale (VAS)
Numeric Rating Scale (NRS)

36. Wong-Baker “Faces Scale”
Verbal scale
Wong-Baker “Faces Scale”

37. ACUTE POSTOPERATIVE MANAGEMENT TOOLS
Pharmaco - Therapy
Regional Techniques
Non Opioid Analgesics
NSAADs
Analgesic /Antipyretic
Analgesic/Anti-inflam/Antipyretic
NSAIDs
Non-selective COX inhibitors
Selective COX-2 inhibitors
Opioids
Weak Opioids.
Strong Opioids.
Mixed agonist-antagonists
Adjuvants
-2 Agonists LA
SP inhibitors
NMDA inhibitors
Anticonvulsant / Antidepressants
Calcitonin
Relaxants
Cannabinoids
Others
Local infiltration
Wound perfusion
Intra-abdominal inj. of LA/Analg.
Intercostal & Interpleural
Paravertebral
USG-RA: e.g. TAP
Neuraxial:
Epidural:
Thoracic
Lumbar
Spinal
Single shot
CSA
CSE

38. WHO Ladder Updated WHO IV Interventional WHO III Strong opioids
Severe pain (7-10)
WHO III Strong opioids
± Adjuvant
Pain Persists or Increases
Moderate pain (4-6)
WHO class II Weak opioids
± Adjuvant
Mild pain (0-3)
By the mouth
By the clock
By the ladder
WHO class I NSAIDs
± Adjuvant

39. WHO (I) Non Opioid Analgesics
NSAADs
Analgesic / Anti-inflam / Antipyretic / Anticoagulant
ASA
Analgesic /Antipyretic
Paracetamol
NSAIDs
Non-selective COX inhibitors:
Diclofenac & Ketoprofen
Selective COX-2 inhibitors
Celecoxib & Rofecoxib
Severe pain (7-10)
WHO class I NSAIDs
WHO class II Weak opioids
WHO III Strong opioids
Mild pain (0-3)
Moderate pain (4-6)
± Adjuvant

40. Scientific Evidence – NON OPIOID ANALGESICS
Paracetamol:
is an effective analgesic for acute pain; the incidence of adverse effects comparable to placebo (Level I [Cochrane Review]).
Paracetamol / NSAIDs given in addition to PCA Opioids   Opioid consumption (Level I).
NSAIDs:
are effective in the treatment of acute postoperative (Level I ).
With careful patient selection and monitoring, the incidence of renal impairment is low (Level I [Cochrane Review]).
NSAIDs + Paracetamol improve analgesia compared with paracetamol alone (Level I).
Acute Pain Management - Scientific Evidence - AAGBI Guidelines 2010

41. WHO Ladder II - Weak Opioids:
Tramadol:
Tramadol : Morphine:
Parenteral = 1 : 10 & Oral = 1 : 5
Dose: 200 – 400 mg/d
Codeine:
Metabolized to morphine.
Codeine : Morphine = 1 : 10
Dextro-propoxyphene:
Methadone Derivative
Prolongation of Q-T interval.
They can relief pain when we increase the dose but with significantly higher incidence of side effects.
Members are:
Tramadol: Equi-potency to morphine:
1:10 Parenteral.
1:5 Oral.
Codeine: Metabolized to morphine.
Equi-potency to morphine: (1:10).
Hydrocodone: Metabolized to Hydromorphine.
Equi-potency to morphine: (1:2).
Dextro-propoxyphene: Methadone Drivative, can cause prolongation of Q-T interval.
Tramadol hydrochloride:
Dose is 100 mg. Equivalent to 100 mg. pethidine.
Less postoperative respiratory depression.
Nausea and vomiting is the prominent side effect.
Efficient in reduction of postoperative shivering.
It is always needed to start with weak opioids before giving strong opioids particularly in cancer patients. They are weak as their affinity to opioid receptors is very much less than strong opioids.
Codeine has to be metabolized to morphine in the body to act. A process which is dependant of metabolic enzymes mainly the Cytochrome oxidase enzyme. Enzyme inhibitors as cimetidine, quinidine, and antifungal drugs can block this reaction and inhibit codeine analgesia.
Dose of codeine is 200 mg, every 4-6 hours.Dose of dihydrocodiene is mg every 4-6 hours
Tramadol on the other hand, is a very weak opioid analgesic. Its analgesia is dependant on potentiation by its serotonergic and noradrenergic effect. It is only potent as an analgesic because of this potentiation that makes it as potent as pethidine. It is also characterized by the absence of tolerance. A very useful weak opioid particularly effective in neuropathic pain.
Dose is 50 mg-100 mg every 6 hours.
Dextropropxyphene: is a weak opioid, its maine side effect is persistent constipation.Dose is 300 mg every 4-6 hours.
Severe pain (7-10)
WHO class I NSAIDs
WHO class II Weak opioids
WHO III Strong opioids
Mild pain (0-3)
Moderate pain (4-6)
± Adjuvant

42. Scientific Evidence – WEAK OPIOIDS
Tramadol:
has a lower risk of respiratory depression & impairs GIT motor function < other opioids
(Level II).
is an effective treatment for neuropathic pain
(Level I [Cochrane Review]).
Dextropropoxyphene:
has low analgesic efficacy
Acute Pain Management - Scientific Evidence - AAGBI Guidelines 2010

43. WHO Ladder III - Strong Opioids
Morphine:
Sedation
PONV
Respiratory Depression
Fentanyl
Rapid action, Short duration.
Fentanyl : Mophine = (1:10)
Pethidene:
Active metabolite:  t½ .
Prolongs Q-T interval.
Pethidine : Mophine = (1:10)
Hydromorphone:
Powerful, rapidly acting.
Release is in distal gut.
Hydromorphone : Morphine = 1 : 5
Severe pain (7-10)
WHO class I NSAIDs
WHO class II Weak opioids
WHO III Strong opioids
Mild pain (0-3)
Moderate pain (4-6)
± Adjuvant
Morphine: available in.
Immediate release( 4 hourly).
Controlled release (12-hourly).
Sustained release (24-hour dosing).
Morphine is a universal opioid agonist, binding to cerebral OR4 is responsible for tolerance.
Oxycodone:
Active on k-opioid receptors: important in visceral and Neuropathic pain.
Double phase of action of SR form: a rapid initial followed by a slow phase.
Equianalgesic dose with morphine for opioid rotation is 2:3.
Fentanyl: (available in a TTS & Transmucosal formulation):
No first path liver metabolism.
Has a specific m & k-opioid receptor binding effect, and no OR4 binding.
Opioid receptor side effects are generally 1/3 of morphine.
Pharmacokinetic and Pharmacodynamic Considerations
1. With opioid drugs, four to five half-lives are required to approach steady state plasma concentrations. Methadone,and levorphanol have relatively long half-lives:
Methadone: from 12 to more than 100 hours.
Levorphanol : from 12 to 16 hours.
Many days may be required to stabilize on methadone after a dose is selected, with possible cumulative toxicity.
2. Transdermal fentanyl has a long apparent half-life (about 24 hours), which results from continued absorption of drug from a subcutaneous depot after the patch is removed.
Controlled-release formulations reach steady state relatively quickly. The transdermal system, for example, usually approaches steady state after 2 to 3 days and the controlled-release morphine and oxycodone preparations approach steady state after 1 to 2 days.
Analgesic duration following a dose is only loosely related to half-life:
Most opioids require a dosing interval of 3 to 4 hours.

44. WHO Ladder IV – Regional Anesthetic Techniques
Local infiltration
Wound perfusion
Intra-abdominal LA
Intercostal
Interpleural
Paravertebral
USG - RA: e.g. TAP
Neuraxial:
Epidural:
Thoracic
Lumbar
Spinal
Single shot
CSA
CSE
WHO III Strong opioids
Mild pain (0-3)
Moderate pain (4-6)
Severe pain (7-10)
± Adjuvant
WHO IV Interventional
WHO class II Weak opioids
WHO class I NSAIDs

45. Neuraxial (Spinal / Epidural) (LA / Opioids / others)
Advantages:
Provide prolonged & effective analgesia
Side effects
Respiratory depression.
N/V.
Pruritis.
Urinary retention.

46. WHO Algorithm for Management of Pain
+ Multidisciplinary:
Adjuvant therapy.
Psychotherapy.
Physioltherapy.
Causal diag. & ttt.
Neuraxial LA
Opioids
WHO III Strong opioids
Plexus block
Paravertebral / PNB
WHO class II Weak opioids
Non-pharmacological
LA infiltration
WHO class I NSAIDs

47. Management Algorithm for Postoperative Pain
Diagnosis
Procedure Specific
Pain manag.
Preventive /
Preemptive
Pain Assessment
ttt of Pain and Co morbidities
1ry Treatment
Supportive Treatment
Pharmacotherapy
Psychological ttt.
Interventional
Physical / Rehab.

48. PACU Discharge Criteria
Fully Awake,
Patent airway,
Good respiratory function,
Stable vital signs,
Patency of tubes, catheters, IV’s
Pain free,
Reassurance of surgical site.

49. Postanesthesia Discharge Scoring System
Vital Signs
(PR & ABP)
Activity
PONV
Pain
Surgical Bleeding
2: Within 20% of preoperative baseline
2: Steady gait, no dizziness
2: Minimal: treat with PO meds
2: Acceptable control per the patient; controlled with PO meds
2: Minimal: no dressing changes required
1: % of preoperative baseline
1: Requires assistance
1: Moderate: treat with IM medications
1: Not acceptable to the patient;
not controlled with PO meds
1: Moderate: up to 2 dressing changes
0: >40% of preoperative baseline
0: Unable to ambulate
0: Continues: repeated treatment
0: Severe
Uncontrolled pain
0: Severe: more than 3 dressing changes

50. Reference book and the relevant page numbers..

51. Thank You 
Dr.
Date: