The Prevalence of Iatrogenic
Underfeeding in the Nutritionally
‘At-Risk’ Critically ill Patient
Rupinder Dhaliwal, RD
Executive Director
Nutrition & Rehabilitation Investigators Consortium
Clinical Evaluation Research Unit
Queen’s University, Kingston, Canada
Introduction
kcal
Critically ill patients receive only 50% prescribed energy and
protein needs
Prescribed Engergy
2000
1800
1600
1400
1200
1000
800
600
400
200
0
Energy Received From Enteral Feed
Caloric
debt
1
3
5
7
9
11
13
15
17
19
21
Days
This “underfeeding”, considered to be IATROGENIC, could lead to
adverse consequences
However, not all critically ill patients seemed to be harmed more as a
consequence of iatrogenic underfeeding
Who benefits from nutrition
therapy in in the ICU?
 Multicenter observational study, 2772 patients
 For every increase of 1000 calories per day
– reduction in overall 60-day mortality (p=0.014)
– increase in ventilator-free days (p=0.003)
 Beneficial treatment effect of increased calories was only
observed in:
– BMI<25 and >35
– no benefit in BMI 25-<35 group
NUTrition Risk in the Critically ill Score (NUTRIC Score)
 severity of the underlying illness
 the degree of acute markers of inflammation and starvation indices
 the degree of chronic markers of inflammation and starvation indices
Helps discriminate which ICU patients will benefit more (or less)
from aggressive protein-energy provision
NUTRIC score ≥ 6 (out of 10) may benefit the most from nutrition
therapy
Mechanically ventilated > 7 days
Underfeeding in pts mechanically ventilated >7 days
WORSE outcomes!
Energy deficit of ~1200 kcals/day is associated with an independent likelihood
of ICU death (Faisy et al British J Nutrition 2009)
Recent randomized trials FAIL to show a difference in
the group that received the most calories
(Casaer et al NEJM 2011, Rice et al Crit Care Med 2011)
Why so?
1. BMI mid ranges
2. Patients young, few comorbidities, so low NUTRIC
3. short stays in ICU (<5 days on average)
What is optimal nutrition?
Heyland DK Crit Care Med 2011
Analyzed patients who were mechanically
ventilated and in the ICU for 96 hrs or >
Receiving up to 80% of their prescribed energy requirements is
associated with a reduced mortality (>80-85% no added effect)
We posit that nutritionally ‘at-risk’ pts should receive at least
80% prescribed needs
Focus on patients that stayed in the ICU ≥ 96 hrs
Objective
• describe the prevalence of “Iatrogenic Underfeeding”
(receiving < 80% prescribed energy and protein) in ICUs
across different Geographic areas
• in ‘high risk’ patients subgroups
– (those with > 7 days of mechanical ventilation)
– body mass index (BMI) of <25 and >35
– those with a NUTRIC score of >6 compared to low risk patients
• to determine those ICU and hospital characteristics associated
with optimal nutrition practice (lowest rates of iatrogenic
underfeeding)
Methods
Analysis of data from




May 11, 2011 prospective, multi-institutional audit
193 ICUs in 29 countries collected data
~20 pts per ICU, ICU LOS at least 96 hrs
3174 mechanically ventilated patients
 Geographical regions
 Sites were divided approximately by continent
– Canada, US separate as many ICUs
 Sites from countries or continents with too few sites to comprise a unique
region were compared to similar region of practice
• Mexico & South Africa
Data Collection
For each patient
 patient characteristics and ICU admission information
 baseline nutrition assessment
 method of calculation (e.g. indirect calorimetry, predictive equations)
 total calories and protein prescribed
 daily nutrition data for first 12 days or IC d/c whatever first
 Route i.e. EN or PN
 total calories and protein prescribed
 patient outcomes
 ICU and hospital discharge
 and mortality.
 Duration of mechanical ventilation
web-based electronic data capture system
Statistical Approach
• adequacy of total nutrition during the first 12 days in ICU
% percent of caloric and protein prescriptions received from EN or PN
• SOFA score and IL-6 was dropped from the original NUTRIC
score
• high vs. Low NUTRIC: according to median NUTRIC Score (i.e. patients
with NUTRIC > median were classified as high risk subgroup)
• multivariable analysis was performed
– to examine the association between the prevalence of iatrogenic
underfeeding
– repeated using three different sets of adjustments to account for
• # days in evaluation (first few days patients receive < 80%)
• added covariates (ICU characteristics and patient characteristics)
• simultaneously included high risk factors in addition to all covariates used
Results
n = 193 ICUs, 29 countries, 3174 patients
Canada: 20 (20%)
Asia: 41 (21%)
USA: 45 (23%)
Europe and
South Africa: 25
(13%)
Latin
America: 24
(12%)
Australia &
New Zealand:
39 (20%)
ICU Characteristics
Characteristics
Total (n=193)
Hospital Type
Teaching
Non-teaching
Size of Hospital (beds)
Mean (Range)
ICU Structure
Open
Closed
Other
Size of ICU (beds)
Mean (Range)
Designated Medical Director
Presence of Dietitian(s)
FTE Dietitians (per 10 beds)
Mean (Range)
149 (77.2%)
44 (22.8%)
633 [100- 2600]
49 (25.4%)
140 (72.5%)
4 (2.1%)
17.7 [5 - 65]
182 (94.3%)
153 (79.3%)
0.4 [0 -3.3]
Results
Patient Flow Diagram
2011 International Nutrition Survey
3747 patients from 193 ICUs
29 countries
573 Excluded from analysis
378 in ICU <96 hours
195 nutritional adequacy not
available for at least 4 days
Total used in analysis
3174 patients from 193 ICUs
29 countries
1812 patients
> 7 days of
mechanical
ventilation
1533 patients
350 patients
1013 patients
with BMI <25
with BMI ≥ 35
with NUTRIC > 4
Patient Characteristics
N
Age (years)
mean (SD)
Sex
Male (%)
Admission
Medical
Total
Canada
Australia
and NZ
USA
Europe and
South Africa
Latin
America
Asia
3174
361
602
670
416
442
683
60.3(17.8)
64.6(16.0)
58.2(17.8)
61.5(17.2)
58.8(17.1)
56.7(19.4)
62.0(17.7)
191 (52.9%) 365 (60.6%) 353 (52.7%) 260 (62.5%) 257 (58.1%) 458 (67.1%)
<0.001
2031
(64.0%)
260 (72.0%) 370 (61.5%) 474 (70.7%) 224 (53.8%) 284 (64.3%) 419 (61.3%)
0.01
Emergent
surgery 782 (24.6%)
35 (9.7%)
74 (12.3%)
53 (7.9%)
56 (13.5%)
28 (6.3%)
115 (16.8%)
66 (18.3%)
158 (26.2%) 143 (21.3%) 136 (32.7%) 130 (29.4%) 149 (21.8%)
76.3(24.5)
78.2(24.2)
81.1(25.2)
86.3(31.9)
77.9( 20.2)
71.3(16.3)
63.6(14.4)
BMI
mean (SD)
26.9(7.5)
27.8(7.6)
27.9(7.7)
29.8(9.9)
26.8(6.5)
25.9(5.1)
23.7(4.7)
APACHE II
mean (SD)
21.9(7.7)
23.7(7.1)
22.2(7.9)
22.4(7.4)
21.5(8.2)
19.9(7.1)
21.9(7.7)
NUTRIC
>4
NUTRIC
<=4
<0.001
1884
(59.4%)
Elective
surgery 361 (11.4%)
Weight (kg)
mean (SD)
p values†
161 (44.6%) 173 (28.7%) 230 (34.3%) 139 (33.4%) 107 (24.2%) 203 (29.7%)
200 (55.4%) 429 (71.3%) 440 (65.7%) 277 (66.6%) 335 (75.8%) 480 (70.3%)
< 0.001
< 0.001
0.06
0.002
Nutrition Outcomes (all patients)
N
Prescribed
kcal/kg/day
Mean (SD)
Adequacy of
calories %
Mean (SD)
Adequacy of
protein %
Mean (SD)
Prevalence of
iatrogenic
underfeeding
Total
Canada
Australia
and NZ
3174
361
602
USA
Europe and
South
Africa
Latin
America
Asia
670
416
442
683
24.6(5)
24. 5(4.6)
25.4 (5.2)
<0.001
78% of patients
failed to meet
≥
25.5(5)
21.5 (6.2)
80% of energy
target
p values†
24.1(5.5)
23.3 (5.3)
56 (30.6 )
63.4(27.3 )
59.5(27.7 )
47.8(27.2 )
54.4(30.3 )
53.4(27.9 )
59.8(37.2 )
<0.001
51.5(29.2 )
59.7(27.2 )
53.9(27.3 )
44.1(27.0 )
49.5(29.6 )
51.1(28.1 )
53.9(32.7 )
<0.001
2467 (77.7%) 255 (70.6%) 450 (74.8%) 599 (89.4%) 309 (74.3%) 372 (84.2%) 482 (70.6%)
<0.001
Time to initiate EN from ICU admission in
hours
Mean (SD)
41.7 (43.6)
37.0 (42.8)
32.6 (39.9)
52.3 (43.8)
39.5 (41.7)
48.6 (42.3)
39.2 (46.4)
<0.001
Nutrition Outcomes: vented > 7 days
Total
MV
>7 days
<7days
Nutritional adequacy
% mean (SD)
Adequacy of calories
56
(30.6 )
62.8
(29.0)**
47.1
(30.5)
Adequacy of protein
51.5
(29.2 )
58.0
(27.7)**
42.9
(29.1)
Time to initiate EN from ICU
admission in hours
41.7
44.1
38.3
Mean (SD)
(43.6 ) (46.9 )** (38.0)
Prevalence of iatrogenic
underfeeding
2467
1295
1172
N (%)
(77.7%) (71.5%)** (86.1%)
> 7 d mechanical ventilation
Better calorie adequacy
Better protein adequacy
Longer to start EN
Lower prevalence underfeeding
(all values p<0.01)
Nutrition Outcomes (BMI)
Total
BMI <≥ 25
35 vs. 25-34
BMI
<25
25-34
≥35
Nutritional adequacy
% mean (SD)
Adequacy of calories
56
(30.6 )
57.8
(32.4)**
54.0
(28.7)
55.6
(29.6)*
Adequacy of protein
51.5
(29.2 )
53.5
(30.2)**
50.1
(28.3)
47.9
(27.7)
Time to initiate EN from ICU
admission in hours
41.7
38.6
44.8
44.4
Mean (SD)
(43.6 )
(41.0 )** (45.6)
(46.2)
Prevalence of iatrogenic
underfeeding
2467
1136
1058
273
N (%)
(77.7%) (74.1%)** (82.0%) (78.0%)
Better calorie adequacy
(p 0.01-0.05)
Better
calorie adequacy
No difference
Better
protein adequacy
No difference
Shorter time to EN
No difference
Lower prevalence underfeeding
all values p<0.01
Nutrition Outcomes (NUTRIC score)
Total
NUTRIC score
>4
<4
NUTRIC Score > 4
Nutritional adequacy
% mean (SD)
Adequacy of calories
56
(30.6 )
55.3
(29.8)
56.4
(31.0)
No difference
Adequacy of protein
51.5
(29.2 )
51.3
(29.1)
51.2
(29.3)
No difference
43.6
(45.0)
40.8
(42.9)
Time to initiate EN from ICU
admission in hours
41.7
Mean (SD)
(43.6 )
Prevalence of iatrogenic
underfeeding
2467
N (%)
(77.7%)
788
1679
(77.8%) (77.7%)
No difference
No difference
Multivariate analysis (odds of receiving <80% of prescription)
Adjusting for number of
days included in nutrition
assessment
Risk Factors of Interest
MV> 7 days (vs. MV ≤ 7 days)
BMI < 25 (vs. BMI between 25 and
35)
BMI > 35 (vs. BMI between 25 and
35)
NUTRIC > 4 (vs. NUTRIC ≤ 4)
Adjusting for all covariates*
but not other risk factors of
interest
Adjusting for all
covariates* and other risk
factors of interest.
OR (95% CI)
p-value
OR (95% CI)
p-value
OR (95% CI)
p-value
0.67 (0.50-0.90)
0.0077
0.69 (0.51-0.93)
0.016
0.68
(0.51-0.92)
0.013
0.0002
0.66
(0.54-0.82)
0.0001
0.0036
0.64
(0.47-0.86)
0.0038
0.86
1.04
(0.79-1.38)
0.75
0.65 (0.54-0.80)
0.64 (0.49-0.84)
1.06 (0.88-1.27)
<0.0001
0.0014
0.55
0.67 (0.54-0.83)
0.64 (0.47-0.86)
1.02 (0.78-1.35)
being mechanically ventilated for more than 7 days
having a BMI <25 and
having a BMI ≥35 were all associated with about a one third reduction in the odds
of receiving <80% of energy prescription
Conclusions
Worldwide, the majority of critically ill patients fail to
receive adequate nutritional intake
This rate of failure varies across geographic regions
High risk patients are less likely to be underfed than low
risk patients but still experience significant underfeeding
Acknowledgements
Daren K. Heyland MD, MSc
Xuran Jiang MSc
Lauren Murch MSc
Andrew G. Day MSc
Clinical Evaluation Research Unit, Kingston General Hospital
Department of Community Health and Epidemiology, Queen’s University
Department of Medicine, Queen’s University
Kingston, ON, Canada
References
•
Alberda C, Gramlich L, Jones NE, Jeejeebhoy K, Day A, Dhaliwal R, Heyland DK. The
relationship between nutritional intake and clinical outcomes in critically ill
patients: Results of an international multicenter observation study. Intensive Care
Med 2009;35(10):1728-37.
•
Faisy C, Lerolle N, Dachraoui F, Savard JF, About I, Tadie JM, Fagon JY. Impact of
energy deficit calculated by a predictive method on outcome in medical patients
requiring prolonged acute mechanical ventilation. British J Nutrition
2009;101:1079-1087.
•
Heyland DK, Dhaliwal R, Jiang X, Day A. Quantifying nutrition risk in the critically ill
patient: The development and initial validation of a novel risk assessment tool.
Critical Care 2011
•
Casaer MP, Mesotten D, Hermans G, et al. Early versus late parenteral nutrition in
critically ill adults. N Engl J Med 2011;June 29 (epub).
•
Rice T, Morgan S, Hays MA, Bernard GR, Jensen GL, Wheeler AP. Randomized trial
of initial trophic versus full-energy nutrition in mechanically ventilated patients
with acute respiratory failure. Crit Care Med 2011;39;967-974.
•
Heyland DK, Cahill N, Day A. Optimal amount of calories for critically ill patients:
Depends on how you slice the cake! Crit Care Med 2011 Jun 23 (epub).
•
Questions?