Table 1.

Physiological and operative severity assessment in the orthopaedic POSSUM system

	Physiologic ill score					Operative severity score
	1	2	4	8		1	2	4	8
Age (years)	<60	61–70	>71		Magnitude	Minor	Inter	Major	Major+
Cardiac signs	Normal	On cardiac drugs or steroid	Oedema Warfarin	Raised JVPa	Number of operative variables within 30 days	1		2	>2
Chest radiograph	Normal		Borderline cardiomegaly	Cardiomegaly	Blood loss per operation (ml)	<100	101–500	501–999	>1,000
Resp signs	Normal	SOBb exertion	SOB stairs	SOB rest	Contamination	None	Incised would, i.e. stab	Minor contamination or necrotic tissue	Gross contamination or necrotic tissue
Chest radiograph	Normal	Mild COADc	Mod COAD	Any other change	Presence of malignancy	None	l0	Node metastases	Distant metastases
Systolic BP (mmHg)	110–130	131–170 100–109	>171 90–99	<89	Timing of operation	Elective		Emergency Resuscitation possible <48 h	Emergency Immediate <6 h
Pulse (/min)	50–80	81–100 40–49	101–120	>121 <39
Como score	15	12–14	9–11	<8
Blood urea (mmol/1)	<7.5	7.6–10	10.1–15	>15.1
Blood Na (mmol/1)	>136	131–135	126–130	<125
Blood K (mmol/l)	3.5–5	3.2–3.4 5.1–5.3	2.9–3.1 5.4–5.9	<2.8 >6
Hb (g/100 ml)	13–16	11–12.9 16.1 to 17	10–11.4 17.1–18	<9.9 >18.1
White cell count (×1012/1)	4–10	10.1–20 3.1–3.9	>20.l <3
ECG	Normal		AFd (60–90)	Any other change

^aJugular venous pressure

^bShortness of breath

^cChronic obstructive airways disease

^dArtrial fibrillation