Tight Glucose Control in Critically Ill
Patients Using a Specialized InsulinNutrition Table
Development Implementation of the SPRINT Protocol
T. Lonergan, J.G. Chase, A. Le Compte, M. Willacy et al.
Department of Mechanical Engineering
Centre for Bio-Engineering
University of Canterbury
Christchurch, New Zealand
Overview
• Background
– Stress-induced hyperglycaemia
– Active Insulin Control (AIC)
• SPRINT
– Introduction
– Development
• Clinical Testing and Results
Background
 Stress-Induced hyperglycaemia prevalent in critical care
 Impaired endogenous insulin production
 Increased effective insulin resistance
 Average blood glucose values > 10mmol/L not uncommon in
some critical care units (over length of stay)
 Tight control  better outcomes:
 Reduced mortality 27-43% (4.0-7.75 mmol/L)
[van den Berghe et al,
2001; Krinsley, 2004; …]
 Reduced length of stay and length of mechanical ventilation
Goal: Keep Blood Glucose ~Normal
(4.0 – 6.0 mmol/L, 75 – 110 dg/mL)
Active Insulin Control Evolution
AIC 1 – 3 Development of Mathematical Model + 1st Trials
 Insulin-only
AIC 4
Computerised Control Protocol
 Insulin + Nutrition
AIC 5
• Develop new protocol with same (or better) control
• Easy to implement in clinical environment
• Compare to international protocols
SPRINT Step 1 = Feed Rate Table
Requires current glucose
measurement and last
hour change in glucose
SPRINT Step 2 = Insulin Table
Requires current glucose
measurement, last hour
change and last hours
insulin bolus
If feed rate = 0 use only insulin wheel
Clinical Testing
• Virtual trials using fitted long term patient data
to create virtual patient responses
– Tests algorithms and methods safely
– Provides insight into potential long term usage
• 33+ Clinical trials in Christchurch ICU
– Clinical proof of concept
– Ethical consent granted by Canterbury Ethics Committee
– Process Improvement Change
Development & Protocol Comparison
SPRINT Protocol
•
Practice
AIC4 Protocol
Mayo Clinic Protocol (Krinsley)
Leuven Protocol (van den Berghe et al)
Goal #1 = SPRINT ≥ Best Clinical
•
Goal #2 = Effectiveness of AIC4
with ease of Leuven Protocol
Bath University Protocol
Yale University Protocol
CDHB Insulin Sliding Scale Protocol
Aggressive Insulin Sliding Scale Protocol
•
Use same virtual trial cohort as
previously to test all protocols
Insulin rate
BG level
Standard
Aggressive
< 4 mmol/L 0 U/hr
0 U/hr
0 U/hr
4 – 5.9 mmol/L
1 U/hr
1 U/hr
6 – 7.9 mmol/L
2 U/hr
2 U/hr
8 – 9.9 mmol/L
3 U/hr
4 U/hr
10 – 11.9 mmol/L
4 U/hr
6 U/hr
12 – 13.9 mmol/L
5 U/hr
6 U/hr
>= 14 mmol/L
6 U/hr
6 U/hr
Protocol Comparison Results
0.4
45%
0.35
SPRINT
0.3
AIC4
Density of measurements
25%
Bath
Leuven
0.25
Mayo Clinic
Yale
Sliding Scale
0.2
Aggressive sliding scale
0.15
Bad!
Also Bad!
0.1
0.05
Very
Bad!
Not Trying?
0
0
2
4
6
8
10
12
Blood glucose level [mmol/L]
14
16
18
20
Clinical Results
• 4688 total hours of control
• 3578 measurements (47.4% two-hourly)
•
•
•
•
Overall Average BG = 5.9 +/- 0.9 mmol/L
Time in 4-6.1 mmol/L = 59.363%
Extremely tight control !
Time in 4-7.0 mmol/L = 86%
Time in 4-7.75 mmol/L = 94%
• Percentage of measurements < 4 mmol/L = 1.8%
• Percentage of measurements < 3 mmol/L = 0.0%
• Minimum 3.1 mmol/L
Clinical Results
• Average Insulin = 2.6 U/hr
• Average Feed = 62% = 1150 kcal/day!!!!
– versus prior hospital rate of 58%!
• Age: Mean = 55, Range = 27-84
•
•
•
•
APACHE II (Risk of Death) = 20 (36.7%)
APACHE III = 58
SAPS II (Risk of Death) = 43 (33.3%)
Mortality (at ICU discharge) = 24.2%
Conclusions
• Implemented tight glycaemic control into the
ICU
–
–
–
–
Developed a simple, easy-to-use system: SPRINT
High compliance by clinical staff due to ease of use
Performance amongst the best in the world
33+ patients and growing
• Clinical results match desired outcomes
– Exceed published protocols by 3-5x on variation
– Better average glucose for same or less insulin
– Much more critically ill cohort
Acknowledgements
Jessica Lin & AIC3
Thomas Lotz
Jason Wong & AIC4
Assoc. Prof. Geoff
Chase
Dunedin
Dr Kirsten
McAuley
AIC2 & Dr. G. Shaw
Mike Willacy
Aaron Le
Compte
The Danes
Prof Steen
Andreassen
Prof Jim Mann
Maths and Stats Gurus
Dr Dom Lee
Dr Bob
Broughton
Prof
Graeme Wake Dr Chris Hann