Preoperative Assessment
ASA Physical Classification System
| I | Healthy patient |
| II | Mild systemic disease - no functional limitation |
| III | Severe systemic disease - definite functional limitation |
| IV | Severe systemic disease that is a constant threat to life |
| V | Moribund patient not expected to survive without the operation |
POSSUM (scoring system for predicting mortality in surgical patients) Parameters included in the scoring system:
- Physiological parameters
- Age
- Cardiac signs
- Systolic BP
- Pulse
- Glasgow coma scale
- Haemaglobin
- WCC
- Urea
- Sodium
- Potassium
- Electrocardiogram
- Operative parameters
- Operative severity
- Multiple procedures
- Total blood loss
- Peritoneal soiling
- Presence of malignancy
- Mode of surgery
Predictive mortality score using the equation: ln [R/(1−R) = −7.04 + 0.13 × physiological score + 0.16 x operative score; where R is the predicted mortality score.