colorectal surgery – outcomes and scoring dermot burke the general infirmary at leeds

Colorectal Surgery – Outcomes and Scoring

Dermot Burke

The General Infirmary at Leeds

Birmingham 37 70Derby County 38 70Sunderland 38 67Preston 37 65Wolves 38 65West Bromwich 37 63Cardiff 38 63Southampton 38 60Stoke City 38 58Colchester 38 53Crystal Palace 37 52Sheffield Wed 38 52Plymouth 36 49Coventry City 38 49Norwich City 37 47Leicester 37 46Ipswich 38 45Burnley 36 41Hull 38 41Southend 38 38Barnsley 37 38QPR 37 37Luton 38 36Leeds United 38 35

Commissioned analysis of surgical performance by using routine data: lessons from Bristol inquiry.

Spiegelhalter DJ, Aylin P, Best NG, Evans SJW, Murray GD.

J R Statist Soc (Ser A) 2002;165:1-31

Colorectal SurgeryWhy Score?

http://heartsurgery.healthcarecommission.org.uk

ASA

1 Fit and well

2 Mild systemic disease

3 Severe, limiting systemic disease

4 Incapacitating systemic disease

5 Moribund

APACHE

APACHE (1981) 34 physiological variables

APACHE II (1985) 12 physiological variables age and chronic health history.

APACHE III (2001) 17 physiologic variablesage and chronic health historyprior treatment location & diagnosis

APACHE IITemperature - core

Mean arterial pressure

Heart rate

Respiratory rate

Oxygenation

FIO2

Arterial pH

Serum sodium

Serum potassium

Serum creatinine

Haematocrit

White blood cell count

APACHE II

Developed for use in intensive care setting

Takes no account of surgical insult

What is POSSUM?

Alien invasion: How the possum became public enemy No 1

What is POSSUM?

Physiological and Operative Severity

Score for the enUmeration of

Morbidity and Mortality

What is POSSUM?

A method of operative risk prediction

that allows for case-mix

What is POSSUM?

18 variables

12 physiological 6 operative

Physiological Operative

Age OperationCardiac status Number of proceduresECG Blood lossRespiratory status Peritoneal contaminationBP Extent of malignancyPulse Elective / emergency GCS HbWCCUreaSodiumPotassium

POSSUM mathsEach factor divided into 1, 2, 3, or 4 levels

weighting of 1, 2, 4 or 8 applied to that level

Amount (ml)

<100

101- 500

501 – 1000

>1000

Weighting

1

2

4

8

Level

1

2

3

4

e.g. blood loss

Original POSSUM equations

MorbidityIn [R/(1-R)] = -5.91 + (0.16*phys score) + ( 0.19*op sev score)

MortalityIn [R/(1-R)] = -7.04 + (0.13*phys score) + ( 0.16*op sev score)

Minimum risk of mortality = 0.40%

P-POSSUM

Minimum risk of mortality = 0.22%

In [R/(1-R)] = -9.06 + (0.169*phys score) + (0.155*op sev score)

CR-POSSUM

Age, Cardiac status, BP, Pulse, Hb, Urea

Operation, Peritoneal contamination,Extent of malignancy, Emergency / Elective

Physiological (6):

Operative (4):

Tekkis et al Br J Surg 2004, 91: 1174-1182

ln[R/(1 − R)] = −9 ・ 167 + (0 ・ 338*phys score) + (0 ・ 308*op sev score)

CR-POSSUM

Minimum risk of mortality = 0.27%

Overpredicts young, fit, elective

Underpredicts elderly, emergency

Tekkis et al Br J Surg 2004, 91: 1174-1182

Validation of CR-POSSUM

Patients(n)

P-POSSUM CR-POSSUM ActualDeaths

General 519 23 (4.4%) 19 (3.7%) 18 (3.5%)

Colorectal 793 36 (4.5%) 25 (3.2%) 28 (3.5%)

Total 1312 59 44 46

Shutt D et al, 2005, ACPGBI

ACPGBI scores

Predictive score for patients with colorectal cancer(age, ASA, stage, urgency, cancer resection)

Predictive model for patients with malignantbowel obstruction (age, ASA, stage, urgency)

Practicalities

Arsenal 12 12 0 0 70 2 68 36 Everton 14 10 3 1 32 13 19 31Charlton Athletic 11 9 1 1 37 13 24 28 Leeds United 11 8 2 1 34 18 16 25Blackburn Rovers 16 7 8 1 29 29 0 22Chelsea 11 6 2 3 25 10 15 21Bristol 11 7 4 0 29 23 6 21Birmingham City 14 4 6 4 22 21 1 16Doncaster Rovers 14 4 9 1 17 35 -18 13Sunderland 17 3 13 1 12 60 -48 10Cardiff City 16 2 11 3 20 40 -20 9Fulham 15 1 14 0 9 72 -6 3

Man Utd 29 23 3 3 66 19 +47 72 Chelsea 28 19 6 3 50 19 +31 63 Liverpool 29 16 5 8 44 20 +24 53 Arsenal 27 15 7 5 50 23 +27 52 Bolton 30 14 6 10 34 34 0 48 Everton 29 11 10 8 37 26 +11 43 Reading 29 13 4 12 43 38 +5 43 Tottenham 30 12 7 11 40 43 -3 43Portsmouth 29 11 8 10 36 31 +5 41 Blackburn 30 12 5 13 35 39 -4 41 Newcastle 29 10 7 12 34 37 -3 37 Middlesborough 29 9 9 11 32 34 -2 36 Aston Villa 28 7 12 9 29 34 -5 33 Fulham 29 7 12 10 31 44 -13 33 Wigan 29 9 5 15 30 44 -14 32 Sheffield Utd 29 8 7 14 25 41 -16 31 Man City 27 8 6 13 20 33 -13 30 Charlton 29 6 6 17 26 49 -23 24 West Ham 30 5 6 19 21 50 -29 21 Watford 29 3 11 15 18 43 -25 20

Man Utd 29 23 3 3 66 19 +47 72 Chelsea 28 19 6 3 50 19 +31 63 Liverpool 29 16 5 8 44 20 +24 53 Arsenal 27 15 7 5 50 23 +27 52 Bolton 30 14 6 10 34 34 0 48 Everton 29 11 10 8 37 26 +11 43 Reading 29 13 4 12 43 38 +5 43 Tottenham 30 12 7 11 40 43 -3 43Portsmouth 29 11 8 10 36 31 +5 41 Blackburn 30 12 5 13 35 39 -4 41 Newcastle 29 10 7 12 34 37 -3 37 Middlesborough 29 9 9 11 32 34 -2 36 Aston Villa 28 7 12 9 29 34 -5 33 Fulham 29 7 12 10 31 44 -13 33 Wigan 29 9 5 15 30 44 -14 32 Sheffield Utd 29 8 7 14 25 41 -16 31 Man City 27 8 6 13 20 33 -13 30 Charlton 29 6 6 17 26 49 -23 24 West Ham 30 5 6 19 21 50 -29 21 Watford 29 3 11 15 18 43 -25 20