Acute postoperative Pain Assessment and

Management

PRESENTED BY

Dr. MAHMOUD A. KAFY

MD Anesthesia & ICU

MINISTRY OF HEALTHFUJAIRAH HOSPITAL

Objectives• Be able to provide a definition for pain

• Have an understanding of pain assessment and pain assessment tools

• Have a knowledge of analgesic drugs and side effects of drugs

• Have an understanding of routes of drug administration

INTRODUCTION

“Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.”IASP (1979)

Definition of pain

• Implies emotional component.• Pain can exist without tissue

damage.

PATHOPHYSIOLOGY OF PAIN

• Involves four physiological processes:

- Transduction

- Transmission

- Modulation

- Perception

Pain Language

• Acute pain: lasts less than 6 months, subsides once the healing process is accomplished.

• Chronic pain: involves complex processes and pathology. Usually involves altered anatomy and neural pathways. It is constant and prolonged, lasting longer than 6 months, and sometimes, for life.

Why Treat Pain?

• Basic human right!

• ↓ pain and suffering

• ↓ complications of unreleived pain

• ↓ chronic pain development

• ↑ patient satisfaction

• ↑ speed of recovery → ↓ length of stay → ↓ cost

• ↑ productivity and quality of life

Barriers to Effective Pain Management

● Multidisciplinary factors

- lack of knowledge

- failure to recognize multi - faceted nature of pain

- poor interpretation of information

● Patient factors

- unwillingness to report pain

- non compliance with treatment

- lack of knowledge / information

COMPLICATIONS OF

UNRELIEVED PAIN

Pain may be undertreated

Physicians may have concern that pain medications will:

- worsen hemodynamic instability - produce harmful or long-lasting metabolites in the

setting of multiple organ dysfunction - Impair the ability to examine a patient’s mental status.

However, these concerns must be balanced against harmful effects of undertreatment of pain.

Adverse effects of unrelieved PainAdverse effects of unrelieved PainCardiovascularCardiovascular Heart Rate

Blood PressureIncreased

myocardial o2

demandHypercoagulation

Unstable anginaMyocardial infarctionDVTPE

RespiratoryRespiratory Lung VolumesDecreased coughRetension of secretion

AtelectasisPneumoniaHypoxemia

GIGI Gastric Emptying Bowel Motility

ConstipationAnorexiaIleus

National Pharmaceutical Council (2001). Macintyre & Schug (2007).Cohen et al (2004)

Adverse effects of unrelieved PainAdverse effects of unrelieved PainNeuroendocrinNeuroendocrinee

Altered release of multiple hormones

HyperglycemiaWt loss/ muscle wastingImpaired wound healingImpaired immune function

MSKMSK Muscle spasmImpaired muscle mobility & function

ImmobilityWeaknessFatigue

PsychologicalPsychological AnxietyFear

Sleep deprivationPost traumatic stress disorder

PAIN PATHWAY

Pain Pathway – Pain Management

Tricyclic AntidepressantsOpioidsSSRI

Anticonvulsants

PAIN ASSESSMENT

Pain Assessment

“One of the most important functions of the nurse is to alleviate the suffering of people who are experiencing pain”

Schofield P(1995)

Why we assess pain ?• To establish degree and nature of pain

• To ensure patient comfort

• To evaluate effectiveness of analgesia

• To help alleviate anxiety

• To decide on type of analgesia

• To aid recovery and prevent complications

When should pain be measured

• Usually asked when pt. are resting .

• Better indicator is assessment of pain during coughing , deep breathing or movement .

• Regular reassessment .

How to assess pain

• Communication with patient is essential

• Observe for changes in physiological signs

• Consider pain as 5th vital sign

• Use a pain scoring system

pain Assessment in Critical Care

In patients who are unable to self-report and in whom motor function is intact and behaviors are observable.The Behavioral Pain Scale (BPS) and the Critical-Care Pain Observation Tool (CPOT) are the most valid and reliable behavioral pain scales for monitoring pain in• Medical ICU• Postoperative, • Trauma (except for brain injury)

In patients who are unable to self-report and in whom motor function is intact and behaviors are observable.The Behavioral Pain Scale (BPS) and the Critical-Care Pain Observation Tool (CPOT) are the most valid and reliable behavioral pain scales for monitoring pain in• Medical ICU• Postoperative, • Trauma (except for brain injury)

Identifying and Treating PainIdentifying and Treating Pain

Patients who can self reportNumerical scale

Guideline do not suggest that vital signs be used alone for pain assessment in adult ICU patients. Guideline suggest that vital signs may be used as a cue to begin further assessment of pain in these patients,

Assess pain ≥ 4 times per shift & as needed

Pain is a more terrible lord of mankind than even death itself”

DO:301DO:301

Pain in the ICU

*CPOT range = 0 – 8, CPOT > 3 is significant

Critical Care Pain Observation Tool* (CPOT)

post operative painmanagement

Management of acute painAnalgesic drugs are used to treat acute pain,

the choice of drug dependent on the intensity of pain being experienced.

Analgesic Ladder

What is the “Best Way” to manage acute pain?

• FIRST , DO NO HARMTherefore , the “best way” is a BALANCE

Patient Safety

Effective AnalgesicModalities

How do we do it?• Multimodal analgesia : Several analgesics with

different mechanisms of action , each working at different sites in the nervous system

• Acetaminophen

• Non-steroidal anti-inflammatory drugs (NSAIDs)

• Opioids

• NMDA Antagonists

• Local anaesthetics

• Non-pharmacologic methods

Methods of administration• Epidural Analgesia• Patient Controlled Analgesia [ intra - venous ]• Intra Muscular Injection• Sub Cutaneous• Oral• Rectal [ suppositories ]• Transdermal• Inhalation [ gas ]• Regional Nerve Blocks e.g. Paravertebral, Brachial Plexus block.• Wound Infiltration

Opioid

Opioid is a blanket term used for any drug which binds to the opioid receptors in the CNS.

Opioids for acute pain (ARI)• Morphine• Diamorphine• Fentanyl • Oxycodone• Tramadol• MST continus• Hydormorphone• Codeine• Dihydrocodeine

Adverse effects of opioids• Respiratory Depression

• Sedation

• Nausea and Vomiting

• Pruritus

• Urinary retention

• Hallucinations

PARACETAMOL

Mechanism of action: ? Selective inhibition of

prostaglandin synthesis in CNS

Analgesic and antipyretic

Oral , rectal and intravenous prep

Useful adjunct

NSAIDS• Work at site of tissue injury to prevent the formation

of the nociceptive mediators Prostaglandins.• Can decrease opioid use ~30% therefore decreasing

opioid-related side effects• NSAIDs should be the first-line drug for treatment

of mild to moderate pain & should be used in combination with opioids for more severe pain .

• Adv. : no sedation , resp. depression , N&V.– Side effects : GI upset , gastric ulcers , decrease

renal medullary blood flow , reversible inhibition of platelet function

NSAIDS• Newer NSAIDS selectively (primarily) inhibit

cyclooxygenase-2 (COX-2) which is induced by surgical trauma with minimal effect on COX-1 which is responsible for GI and platelet side effects

• Equivalent analgesic efficacy with non-selective COX-inhibitors

• No effects on platelets!

• Much reduced incidence of upper GI S/E compared to non-selective

• Duration of action about 24 hr.

NMDA Receptor Antagonists • Ketamine : - Ketamine 0.15 - 0.3 mg/kg IV with induction of

general anesthesia has pre-emptive analgesic effects - less pain and less opioid use post-op

- Low dose (0.25-0.5 mg/kg) IV bolus followed by infusion of 2-4 µg/kg/min , can provide significant analgesia.

- Ketamine as co-analgesic , combined 1:1 with morphine IV PCA . Better analgesia , less S/E

Dexmedetomidine :- Highly selective - Highly selective αα22 agonist. agonist.

- Does not depress the respiratory drive.- Does not depress the respiratory drive.

- Causes- Analgesia dose-dependent , sedation - Causes- Analgesia dose-dependent , sedation (“(“Cooperative sedationCooperative sedation”), anxiolysis.”), anxiolysis.

- Reduction in Sympathetic tone.- Reduction in Sympathetic tone.- Useful adjunct to both opioid & non-opioid analgesicUseful adjunct to both opioid & non-opioid analgesic.- Side effects : Bradycardia , Hypotension

- Dose : Loading dose – 1 µg/kg i.v. over 10 min , followed by infusion of 0.2-0.7 µg/kg/hr.

- Metabolised by liver & excreted in urine.

NON PHARMACOLOGICAL METHODS

• CRYOTHERAPY

• TENS

• ACUPUNCTURE

THANK YOU