文档介绍：Management of Postoperative Pain
Dr Alice Man
Department of Anaesthesia & Intensive Care
The Chinese University of Hong Kong
Prince of Wales Hospital
“By any reasonable code, freedom from pain should be a basic human right, limited only by our knowledge to achieve it”
Liebeskind JC & Melzack R
IASP definition of Pain:
An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.
Physiological mechanism of acute pain:
Nociceptors
Peripheral chemical mediators
Pain transmission pathways
Pain modulation
Why should we treat postoperative pain?
Possible harmful effects of untreated severe acute pain:
A. Cardiovascular- activation of sympathetic nervous system→
hypertension, tachycardia, ↑ myocardial contraction, vascular resistance→↑ myocardial O2 demand
decreased coronary vasoconstriction→↓ myocardial O2 supply
→myocardial ischaemia
B. Respiratory- surgical incision and pain→
splinting diaphragm, reflex inhibition of phrenic nerve→ decreased lung volume, atelectasis
poor cough, sputum retention→postoperative pneumonia, hypoxaemia
C. Gastrointestinal- activation of spinal reflex arc→impaired gastric and intestinal motility→ ileus
D. Genitourinary- Urinary retention
E. Neuroendocrine: release of stress hormones . catecholamines, GH, cortisol, glucagons ACTH, ADH, rennin, angiotensi