Role of Anaesthesiologist in

Management of Cancer Pain

Co – ordinator: Dr. Veena GuptaSpeaker: Anand Maurya

What is Cancer? Cancer is the uncontrolled growth of abnormal cells in the

body, Cancerous cells are also called malignant cells.

Cancer grows out of normal cells in the body.

Normal cells multiply when the body needs them, and die when the body doesn't need them.

Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly.

Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.

Cancer Pain Approximately 19 million people worldwide experience cancer

pain every year.

Of these, 40–80% suffer from moderate to severe pain.

Their pain may be due to the

Cancerous lesion itself,

Metastatic disease,

Complications such as neural compression or infections,

Chemotherapy Treatment, or

Totally unrelated factors.

The pain manager must therefore have a good understanding of the nature of the cancer, its stage, the presence of metastatic disease, and treatments.

Components of Cancer Pain Somatic Pain

Dull, sharp, localized

Tumor / Mass effect

Musculoskeletal involvement

Visceral Pain

Deep, squeezing, not well-localized

Infiltration, compression, extension, or stretching of the thoracic, abdominal, or pelvic viscera

Referred pain

Neuropathic Pain

Shooting, sharp, burning, “pins & needles”

CA compressing or infiltrating nerves/nerve roots/blood supply to nerve

Nerve damage from treatments

Effects of Pain Physiological

Increased catabolic demands: poor wound healing, weakness, muscle breakdown

Decreased limb movement: increased risk of DVT/PE

Respiratory effects: shallow breathing, tachypnea, cough suppression increasing risk of pneumonia and atelectasis.

Increased sodium and water retention

Decreased gastrointestinal mobility

Tachycardia and elevated blood pressure

Psychological

Negative emotions: anxiety, depression

Sleep deprivation

Existential suffering

What Does Pain Mean to Patients? Poor prognosis or impending death

Particularly when pain worsens

Decreased autonomy

Impaired physical and social function

Decreased enjoyment and quality of life

Challenges to dignity

Threat of increased physical suffering

Patient Pain History Onset / duration

Quality?

Site(s) of pain/radiation?

Severity of pain?

What aggravates or relieves pain?

Impact on sleep, mood, activity?

Effectiveness of medication?

Pharmacologic Management Opioids

Tramadol Morphine Fentanyl Codeine Oxycodone Hydrocodone Methadone

Non-opioid therapy / Co-analgesics NSAIDS Acetaminophen Topicals

• Lidocaine, Capsaicin

Practice Points:o Mild paino “ceiling” effecto Start at lowest effective

doseo Review pt’s underlying

medical illnesses

Practice Points:o If pain constant/chronic –

use long-acting opioids with short-acting for breakthrough

o Breakthrough dose - 10-20% of total daily dose

o Assess pt’s clinical and financial situation before prescribing

Adjuvants Antidepressants

• TCAs for neuropathic pain Anticonvulsants Corticosteroids Neuroleptics Alpha2 – agonists Benzodiazepines Antispasmodics Muscle relaxants NMDA-blockers Systemic local anesthetics

Practice Points:o Choose adjuvant

carefully (risk:benefit)o Start low and titrate

graduallyo Avoid initiating several

adjuvants concurrently

Non-Pharmacologic Management Acupuncture

Yoga

Guided imagery

Cold/heat

Massage

Vibration

TENS units

Exercise programs

Hypnosis

Counseling

WHO Ladder

Role of Anaesthesia Interventions

Palliative surgery Kyphoplasty/Vertebroplasty

Sedation

Nerve Blocks

Epidural

Intrathecal pain pumps

Lidocaine infusion

Nerve Blocks for Pain Relief A nerve block relieves pain by interrupting how pain signals are

sent to your brain. It is done by injecting a substance, such as alcohol or phenol, into or around a nerve or into the spine.

Nerve blocks may be used for several purposes, such as:

To determine the source of pain.

To treat painful conditions.

To predict how pain will respond to long-term treatments.

For short-term pain relief after some surgeries and other procedures.

For anesthesia during some smaller procedures, such as finger surgery.

Nerve blocks are used to treat chronic pain when drugs or other treatments do not control pain or cause bad side effects.

A test block is usually performed with local anesthetic.

Types of Sympathetic Block Diagnostic blocks are used to assess the sympathetic

component of pain.

To define the sympathetic contribution to any particular pain syndrome, the diagnostic block must be a pure sympathetic block without any accompanying somatic block.

Use of diagnostic blocks is difficult and often inaccurate. Increasing skin temperature, decreasing pain, and anhydrosis in the distal extremity may indicate a successful sympathectomy.

Prognostic blocks can be used to try to test the effect on pain, blood flow, or sweating, but there may be a poor correlation between the prognostic block and the outcome of any subsequent surgical or neuroablative procedure.

Therapeutic blocks may be performed with local anaesthetics, neurolytic chemicals such as phenol or alcohol, neuroablative techniques such as radiofrequency lesioning, or with drugs such as guanethidine and bretylium in i.v. regional techniques.

Drugs and Techniques Local anaesthetics are used for diagnostic, prognostic, and

therapeutic blocks.

Lidocaine 1% is suitable for a diagnostic block, but bupivacaine 0.25–0.5% is often preferred for other blocks.

Neurolytic solutions are used for therapeutic blocks; the most common are phenol and alcohol.

Phenol destroys both motor and sensory nerve fibres by protein denaturation; at a concentration of 2–3% in saline, phenol seems to spare motor function.

As fibres can regenerate, these blocks are not permanent. Phenol is not as effective as alcohol in destroying the nerve cell body and its effect tends to be less profound and of shorter duration than alcohol.

Alcohol has a similar non-selective destructive action on nerves, but it produces a very high incidence of neuritis. Although 50–100% alcohol is used as a neurolytic, a local anaesthetic is commonly used as a diluent.