ICNARC Case Mix Programme for Cardiothoracic Intensive

Care Units

Stephen T Webb Papworth Hospital

Declarations of interest

• CIA Linkman for ICNARC

• Co-applicant on current NIHR Health Service & Delivery Research grant application with ICNARC

• ‘Friend of ICNARC’ offered free delegate registration at the CMP Annual Meeting in London

• No financial declarations of interest

Outline

• ICNARC Case Mix Programme

• The ICNARC (risk prediction) Model

• ARCtIC - Assessment of Risk in Cardiothoracic Intensive Care

• Risk prediction models for cardiothoracic ICUs

• What could your unit get out of the ICNARC CMP?

• How could your unit’s ICNARC CMP data be used?

• Future developments

A question…

• How do you know your cardiothoracic ICU is providing ‘high quality care for all, now and for future generations’?

A question for your cardiothoracic ICU…?

• How do you know your cardiothoracic ICU is providing ‘high quality care for all, now and for future generations’?

• Structures - operational policies, staffing and equipment e.g. FICM Core Standards for ICUs, National Cardiac Benchmarking Collaborative (NCBC)

• Processes - local procedures and guidance e.g. NICE Quality Standards, CIA Quality Standards

• Outcomes - clinical outcomes e.g. National Clinical Audit

Faculty of Intensive Care MedicineCore Standards for Intensive Care Units 2013

4.2 The Intensive Care Unit should participate in a national database for adult critical care

ICUs must publish the nationally agreed dashboard, including the standardised mortality rate

Intensive Care National Audit & Research Centre (ICNARC) - Case Mix Programme (CMP)

• Comparative audit of patient outcomes from adult critical care units in NHS and independent hospitals in England, Wales & Northern Ireland

• Recognised national clinical audit by the National Advisory Group for Clinical Audit & Enquiries (NAGCAE), accepted by the Department of Health Quality Accounts

• 95% of adult general ICUs/HDUs participate as well as specialist neurosciences and cardiothoracic units

• Launched 1994, 1.5 million admissions

• Scotland - Scottish Intensive Care Society Audit Group (SICSAG) Database

Risk models for comparative clinical audit

• Risk models are needed to make ‘fair comparisons’ - taking into account differences in patient characteristics that would be expected to result in differences in outcomes

• The probability of mortality is calculated for each patient using the risk prediction model

• The probability of mortality for each patient in a group of patients is summed to calculate the ‘expected’ number of deaths

• The ‘expected’ number of deaths can then be compared to the ‘observed’ (actual) number of deaths

The ICNARC Model - risk factors

• Age

• CPR within 24 hours prior to admission

• Source of admission and surgical urgency

• Reason for admission

• ICNARC Physiology Score - weightings for derangements in 12 physiological variables

• Interactions between reason for admission and physiological variables

• An interaction refers to the variation of one variable according to the value of another

• Different relationship between physiological variables and acute hospital mortality in certain reasons for admission

The ICNARC Model - repeated recalibration of the model over time

The ICNARC Model - acute hospital mortality in a single unit over time - EWMA chart

The ICNARC Model - acute hospital mortality ratio compared with other units - funnel plot

Cardiothoracic ICUs v General ICUs - what’s the difference?

• Case mix of most cardiothoracic ICUs is predominantly cardiac surgery patients (although there may be changes over time - cardiology, transplant, ECMO)

• Higher number of admissions, shorter length of stay, lower mortality

• Cardiac surgery patients were specifically excluded from most risk models (APACHE II, SAPS II)

• The ICNARC Model was developed and validated using data from adult general ICUs only

• Cardiopulmonary bypass transiently affects postoperative physiological variables

• Deranged physiological variables may be masked by supportive therapy (MV, RRT, PMs, IABPs, ECMO, VADs…)

ARCtIC - Assessment of Risk in Cardiothoracic Intensive Care

• Group of intensivists interested in outcome measurement in cardiothoracic ICUs

• Led by ACTA - CIA (Cardiothoracic Intensivists in ACTA)

• Hosted by ICNARC

• Supported by other professional societies - SCTS, BCIS

• Developing potential for data linkage with other national clinical audits hosted by National Institute for Cardiovascular Outcomes Research (NICOR)

• National Adult Cardiac Surgery Audit (NACSA)

• National Audit of Percutaneous Coronary Intervention (NAPCI)

Systematic review - risk prediction models for acute hospital mortality in cardiothoracic ICUs

• Systematic electronic search, 8929 citations identified, 12 met inclusion criteria

• Variable objectives, risk factors, outcomes and definitions

• Risk factor selection and risk modelling strategies not specified

• Sample sizes inadequate to obtain reliable estimates

• Minimal data for specific risk prediction models for cardiothoracic ICUs

The ICNARC Model (Cardio 2013)

• Aim - recalibration of the current ICNARC Model to admissions to cardiothoracic ICUs

• 5 cardiothoracic ICUs participating in CMP

• 12303 admissions

• Jan 2011 - Dec 2012 (2 years)

• Same risk factors in the ICNARC Model (Cardio 2013) as in the standard ICNARC Model

• New coefficients were calculated for existing risk factors

• New interactions between reason for admission and physiological variables

Specific risk prediction model for cardiothoracic ICUs

• Aim - development of a specific risk prediction model for cardiothoracic ICUs

• 5 cardiothoracic ICUs participating in CMP

• 17002 admissions

• Jan 2010 - Dec 2012 (3 years)

Dataset - Patient characteristics Age, median (iqr) 65 (58, 75)

Male, n (%) 11,736 (69.0)

Severe co-morbidities, n (%)

Any severe co-morbidity 2,535 (14.9)

Very severe cardiovascular disease 1,470 (8.6)

Severe respiratory disease 517 (3.0)

Chronic renal replacement therapy 175 (1.0)

Chronic liver disease 44 ( 0.3)

Hematologic malignancy 95 ( 0.6)

Metastatic disease 172 (1.0)

Immunocompromise 394 (2.3)

Activities of daily living, n (%)

No assistance 13,986 (82.3)

Partial assistance 2,994 (17.6)

Total assistance 22 (0.1)

CPR prior to admission, n (%) 701 (4.1)

ICNARC Physiology Score, median (iqr) 13 (10,18)

Dataset - Source of admission & Reason for admission

Location prior to admission, n (%)

Theatre – elective/scheduled surgery 11,779 (69.4)

Theatre – urgent/emergency surgery 1,186 (7.0)

Ward or intermediate care 2,099 (12.4)

Other critical care unit 1,242 (7.3)

ED, other hospital or not in hospital 677 (4.0)

Primary reason for admission, n (%)

Surgical 12,970 (76.3)

Cardiothoracic surgery 11,774 (90.8)

Other 1,196 (9.2)

Non-surgical 4,032 (23.7)

Cardiovascular 1,926 (47.8)

Respiratory 1,548 (38.4)

Other 558 (13.8)

Dataset - Length of stay & Mortality

Length of stay (days), median (iqr) Cardiothoracic ICUs Other units in CMP

Critical care unit stay 1 (1, 3) 2 (1,5)

Hospital stay 10 (7, 19) 12 (5,25)

Mortality, n (%)

Critical care unit mortality 1,251 (7.4) 61,472 (14.5)

Acute hospital mortality 1,881 (11.1) 92,844 (22.0)

Specific risk prediction model for cardiothoracic ICUs

• Aim - development of a specific risk prediction model for cardiothoracic ICUs

• 5 cardiothoracic ICUs participating in CMP

• 17002 admissions

• Jan 2010 - Dec 2012 (3 years)

• New risk factors based on admission data and physiological variables

• New interactions between cardiothoracic surgery as reason for admission and physiological variables

• Acceptable statistical performance

New risk prediction model for all units

• Aim - development of a new risk prediction model which performs well for all types of adult critical care unit

• 232 units, including all types of unit

• 156176 admissions

• Jan 2012 - Dec 2012 (1 year)

• New approach to missing data, new statistical methods for modelling physiology, new data fields, new coding method for reason for admission, new interactions

New risk prediction model for all units

• Aim - development of a new risk prediction model which performs well for all types of adult critical care unit

• 232 units, including all types of unit

• 156176 admissions

• Jan 2012 - Dec 2012 (1 year)

• New approach to missing data, new statistical methods for modelling physiology, new data fields, new coding method for reason for admission, new interactions

• All types of unit - improved statistical performance compared to current ICNARC Model

• Cardiothoracic ICUs - similar statistical performance compared to ICNARC Model (Cardio 2013)

Which risk prediction model for cardiothoracic ICUs?

• Currently - ICNARC Model (Cardio 2013)

• Future - specific model for cardiothoracic ICUs or new model for all types of unit?

• Specific model for cardiothoracic ICUs - small number of units and relatively small number of admissions in dataset, less up-to-date dataset

• New model for all types of unit - large number of units and admissions in dataset (including cardiothoracic ICUs), more up-to-date dataset, allows comparison across different types of units

What could your cardiothoracic unit get out of the ICNARC CMP?

What could your cardiothoracic unit get out of the ICNARC CMP?

What could your cardiothoracic unit get out of the ICNARC CMP?

What could your cardiothoracic unit get out of the ICNARC CMP?

What could your cardiothoracic unit get out of the ICNARC CMP?

How could your cardiothoracic ICU’s ICNARC CMP data be used?

• Local reporting

• Data Analysis Report

• Regional reporting

• Operational Delivery Network

• National reporting

• CMP Annual Quality Report

• NHS England Specialised Commissioning - Adult Critical Care Quality Dashboard

• Department of Health Quality Account

• Care Quality Commission - Acute Hospital Inspections

Summary

• ICNARC CMP is a national clinical audit which cardiothoracic ICUs can participate in

• The ICNARC Model (Cardio 2013) is used for cardiothoracic ICUs in the CMP

• New risk prediction models are being developed

• CMP data can be used for local quality improvement, compared with other cardiothoracic ICUs and shared with other organisations

• CIA and ICNARC are keen to work together in the future - your cardiothoracic ICU can get involved…

Acknowledgements

• ICNARC: Kathy Rowan, David Harrison, Lucy Lloyd-Scott, Paloma Ferrando, Jason Shahin

• Funding: NIHR Health Services & Delivery Research Programme (Project Number 09/2000/65)

• ACTA & CIA: Alistair Macfie, Nick Fletcher, Ruth Hurley, Kamen Valchanov, Mahesh Prabhu, Nick Schofield

• 8 cardiothoracic ICUs currently participating in CMP: Newcastle, Middlesborough, Hull, Sheffield, Liverpool, Leicester, Papworth, St George’s

Thanks …..Questions