Transcript Enteral vs parenteral nutrition in critically ill adult

Neil Mclean
March 12, 2009
Case

You are working in the ICU and receive a patient
from the OR. He is a 25 year old male who was
involved in an MVC. His injuries include a severe
closed head injury, a L hemopneumothorax with a
chest tube in place, a splenic rupture (splenectomy
performed) a grade 1 liver laceration, a L femur
fracture (fixed). He is intubated and has an EVD in
place. Upon admission, he is hemodynamically
stable and you have done all the other right things.

You are now at the section in the pre-printed orders
about options for feeding, You can choose between
Parenteral Nutrition or Enteral Nutrition
Question #1 Does enteral nutrition compared to
parenteral nutrition result in better results in critically ill
adult patients? (MARIOS)
An ongoing saga…
“…parenteral nutrition was an independent predictor of death (odds ratio
of 2.09).
The adverse sequelae associated with parenteral nutrition result from 1) not
directly feeding the bowel; 2) the metabolic, immunologic, endocrine, and
infective complications associated with parenteral nutrition; and 3) the fact that
parenteral nutrition is infused into the patient’s systemic venous system,
bypassing the liver.”
Critical Care Medicine, 36(6) pp 1964-1965
This is all very confusing…
Let’s turn to meta-analyses of RCTs for
more clarity on the matter…
Thomson A. The enteral versus parenteral nutrition debate revisited. JPEN J. Parenter Enteral Nutr.2008; 32:474
Is TPN really protective?
Simpson F, Doig G. Parenteral vs enteral nutrition in the critically ill patient: a meta-analysis of trials using the intention to treat principle. Intensive Care Med. 2005
Is TPN really protective?
Simpson F, Doig G. Parenteral vs enteral nutrition in the critically ill patient: a meta-analysis of trials using the intention to treat principle. Intensive Care Med. 2005
Thomson A. The enteral versus parenteral nutrition debate revisited. JPEN J. Parenter Enteral Nutr.2008; 32:474 -481
MORTALITY
www.criticalcarenutrition.com
MORTALITY
PN calories > EN calories
www.criticalcarenutrition.com
MORTALITY
PN calories = EN calories
www.criticalcarenutrition.com
MORTALITY
PN blood sugars > EN blood
sugars
www.criticalcarenutrition.com
INFECTIOUS COMPLICATIONS
ARR = 0.17; NNT = 5.7
www.criticalcarenutrition.com
INFECTIONS
PN calories > EN calories
www.criticalcarenutrition.com
INFECTIONS
PN calories = EN calories
www.criticalcarenutrition.com
INFECTIONS
PN blood sugars > EN blood
sugars
www.criticalcarenutrition.com
GUIDELINE CONCLUSIONS
1.
The use of EN compared to PN is not associated with a
reduction in mortality in critically ill patients.
1.
The use of EN compared to PN is associated with a significant
reduction in the number of infectious complications in the
critically ill.
1.
No difference found in ventilator days or LOS between
groups receiving EN or PN.
1.
Insufficient data to comment on other complications;
hyperglycemia or higher calories not found to result in higher
mortality of infections.
1.
EN is associated with a cost savings when compared to PN.
www.criticalcarenutrition.com
www.criticalcarenutrition.com
WHAT DOES THIS TELL ME?

Despite having clinical practice guidelines, route of nutrition is a
topic that remains controversial.

As far as I can tell, the take home message should be:
1.
Try to use EN if you can as it will decrease infectious
complications, is cheaper, and will instantaneously give you
another lumen.
1.
Supplementing inadequate EN with PN has not been shown to
be beneficial.
1.
If you can’t use EN, PN is fine, though it may increase your rate
of infections but not your LOS or mortality (this may only
occur in patients that are overfed with PN however).

You decide to feed this patient enterally via
an NG tube. You ask your resident about
starting to feed the patient and he says, “you
know he has had a really tough day, why
don’t we wait until the morning to start his
feeds”
Why feed early?
Early EN improves wounds healing and
host immune function
 Decreases hypermetabolic response to
tissue injury
 Preserves intestinal mucosal integrity
 Two meta-analysis recently published
evalu

Crit Care Med 2001;29(12):2264-2270
15 studies
 All surgical patients
 Early defined as < 36Hrs post admission
or surgery

Crit Care Med 2001;29(12):2264-2270
Crit Care Med 2001;29(12):2264-2270
• Mean Reduction in length of stay 2.2 days (CI 0.81-3.63)
Crit Care Med 2001;29(12):2264-2270
Mortality in early 8 % vs 11.5% in delayed EN.
Not statistically significant: RR 0.74 (0,37-1.48)
Crit Care Med 2001;29(12):2264-2270
• 8 “level 2” RCTs
•Defined early as within feeds started within 24-48hrs of admission
•Only mechanically ventilated patients
Trend towards decrease mortality
Heyland et al, JPEN, 2003; 27: 355-373
• Trend toward decrease infectious complications
• Final Recommendation:
Recommend early EN within 24-48H after
admission to ICU
Heyland et al, JPEN, 2003; 27: 355-373
Conclusion
Early EN is associated with a trend
towards a reduction in mortality in
critically ill patients.
 Early EN is associated with a significant
reduction in infectious complications
 Early EN has no effect on ICU or hospital
length of stay
 Early EN improves nutritional intake.

CriticalcareNutrition.com
Early aggressive vs early lower EN?
CMAJ, 2004; 170 (2):197-204.
CMAJ, 2004; 170 (2):197-204.
• Intervention groups received more calories per day: 1264 Kcal vs 998
Kcal
• Achieve 80% of goal feeds: 5.1 vs 4.8 days!
• Significant shorter hospital stay
• Trend toward decrease mortality
CMAJ, 2004; 170 (2):197-204.
• Conclusions:
• May be associated with a reduction in mortality in the critically ill
patient
• May be associated with a reduction in hospital lengths of stay in
the critically ill patient
• Is associated with a trend towards a reduction in the # infections and
complications in head injured patients.
• Results in a significantly higher calorie intake/lower calorie deficit in
head injured patients and other critically ill patients.

So the resident agrees to start feeding
and now asks you how much do I order?
Question #3 Discuss the tools for
estimating enteral feeding requirements in
the critically ill adult patient. Please
include a discussion of indirect calorimetry
(TODD)


You initiate enteral feeding. A few hours
later the nurse calls you to tell you that the
patient gastric residuals are high.

Question #4 Does the use of a promotility
agent impact patient outcome? ( please
discuss some of the options for promotility
agents) (SCOTT)

40-50% of critically ill patients experience
some degree of slow gastric emptying
 Increases risk of reflux and aspiration, as well as
suboptimal nutrition.
Options are prokinetics (maxeran,
erythromycin, naloxone,
?methylnaltrexone), postpyloric feeding, or
TPN.
 Regarding prokinetics little (if any)
evidence exists regarding impact on “hard”
outcomes.


Metoclopramide (maxeran), a dopamine
antagonist has been shown to:
 Improve gastric emptying in critically ill
patients after a single dose.
 Effect on the longer term success of feeding
unknown.

Erythromycin (3mg/kg) has been shown
to:
 Increase gastric emptying.
 Improve feeding success in previously feed
intolerant patients.
Erythromycin vs. metoclopromide
vs. both
 Single double blind RCT (Nguyen, 2007) showed




erythromycin 200 mg bid was more effective in reducing
gastric residuals than maxeran 10 mg IV bid, but both
treatments had rapid tachyphylaxis.
Combination rescue therapy was highly effective and had
less tachyphylaxis.
A separate study confirmed that combination therapy was
more effective than erythromycin alone in reducing gastric
residuals.
Combination therapy has also been found to result in a
significant higher calorie intake, lower gastric residual
volumes and lower need for post pyloric feeds.
Concerns around routine erythromycin use include
bacterial resistance, the potential for cardiac toxicity and
tachyphylaxis.
Other outcomes
Multiple studies show benefit of promotility
agents on overall nutritional intake.
 In five studies of either maxeran or
erythromycin used alone, no mortality
benefit has been demonstrated.
 In three studies looking at pneumonia or
infection rates, only one (using naloxone),
showed a significant reduction in
pneumonia. The other two (using
maxeran) showed no difference in
pneumonia or infection rates.

Other outcomes - cont’d.
LOS, ventilator days - no differences have
been shown in three studies that looked at
these outcomes.
 Conclusion:
 1) Motility agents have no effect on
mortality or infectious complications in
critically ill patients.
 2) Motility agents may be associated with
an increase in gastric emptying, a
reduction in feeding intolerance and a
greater caloric intake in critically ill patients.

Recommendation
Based on 1 level 1 study and 5 level 2 studies, in
critically ill patients who experience feed
intolerance (high gastric residuals, emesis), we
recommend the use of a promotility agent. Given
the safety concerns associated with erythromycin,
the recommendation is made for metoclopramide.
 There are insufficient data to make a
recommendation about the use of combined use
of metoclopramide and erythromycin.
 Other steps to reduce feeding intolerance and
aspiration risk include head of bed elevation,
control of pain and other contributing factors like
hypotension and sepsis, avoidance of opiates.


Question #5 Are there other techniques
to ensure adequate nutrition? Please
discuss the utility of small bowel feeding,
use of feeding protocols, body position.
(NAISAN)
Question #5 Are there other techniques to
ensure adequate nutrition?
If serious concern about GI tract not
working then TPN
 Already heard not the best option
 Other options include a feeding protocol
with early use of duodenal tube, and
prokinetics

Duodenal tube
Based on 11 level 2 studies, small bowel
feeding compared to gastric feeding
may be associated with a reduction in
pneumonia in critically ill patients.
 Mortality: Based on the 9 studies that
reported on mortality, no significant
differences between the groups were
found (RR 0.93, 0.72-1.20, p = 0.6)

Duodenal tube

infections: Based on the 9 studies that
reported on infections, the meta-analysis
showed that small bowel feeding was
associated with a significant reduction in
infections (RR 0.77, 0.60-1.00, p =
0.05)
Duodenal feeding

Based on the 5 studies that reported the
LOS, a trend towards a reduction in ICU
LOS with gastric feeding was seen.
The presence of significant statistical
heterogeneity weakens this estimate
Head Injuries

The group that had a more aggressive
feeding regimen and small bowel
feeding (Taylor) had fewer major
complications and a better neurological
outcome at 3 months than the group
receiving gastric feeds

Taylor SJ et al. Prospective, randomized, controlled trial to determine the effect of
early enhanced enteral nutrition on clinical outcome in mechanically ventilated
patients suffering head injury. Crit Care Med 1999;27:2525-31.
Duodenal feeding
Conclusions:
1) Small bowel feeding, compared to
gastric feeding maybe associated with a
reduction in pneumonia in critically ill
patients.
 2) No difference in mortality or ventilator
days in critically ill patients receiving small
bowel vs.gastric feedings.
 3) Small bowel feeding improves calorie
and protein intake and is associated with
less time taken to reach target rate of
enteral nutrition when compared to gastric
feeding.


Duodenal feeds

In units where obtaining access is
difficult, small bowel feedings should be
considered for patients at high risk for
intolerance
 (on inotropes, continuous infusion of
sedatives, or paralytic agents, or patients
with high nasogastric drainage)
 or at high risk for regurgitation and
aspiration (nursed in supine position)
Feeding Protocols

There were 3 trials that demonstrated an
improvement in nutritional outcomes (i.e.
residual volumes, time to reach goal rate
of EN, etc) with the use of a feeding
protocol
Feeding Protocols
There was 1 level 2 study that compared
outcomes of a protocol with a higher
gastric residual volume threshold (250 ml)
+ mandatory prokinetics to a feeding
protocol with a lower gastric residual
volume threshold (150 mls) (Pinilla 2001)
 two cluster RCTs evaluated the effect of an
enhanced feeding protocol as one of
several interventions geared towards
optimizing nutrition (Martin 2004, Doig
2008)

Feeding Protocols
Mortality: Only one study reported on
mortality (Martin 2004) and there was a
trend towards a reduction in hospital
mortality (p=0.058)
 Infections: The incidence did not differ
between groups in the study that
reported on this outcome (Pinilla 2001)

LOS and Ventilator days: In both
cluster randomized controlled trials, no
differences in ICU length of stay was
observed,
 however, the hospital length of stay was
significantly lower in the ICUs that
received the evidence based algorithms
in one trial (p=0.003, Martin 2004)

Feeding Protocols
in the study by Pinilla et al, there was a
lower number of elevated gastric
residuals in the group that received the
protocol with higher residual volume
threshold + prokinetics (p<0.005)
 Also a trend towards less time taken to
reach goal rate of feeding(p<0.09)

Feeding Protocol
The # days 100% goal calories were
met was higher in the ICUs that were
randomized to the feeding protocol
group in the Doig study (p=0.03)
 The time from ICU admission to start of
feeds was lower in the ICUs that were
randomized to the algorithm
group/practice change group in both
cluster trials (Martin 2004 p=0.17, Doig
2008 p<0.001)

Feeding Protocols
Conclusions:
1) Feeding protocols/algorithms with
prokinetics, post-pyloric tubes may be
associated with a trend towards a reduction
in hospital mortality and a significant
reduction in hospital length of stay.
 2) Feeding protocols with prokinetics and
a higher gastric residual threshold (250
mls) are associated with a trend towards a
reduction in gastric residual aspirations and
less time taken to reach goal feeding rate
in the critically ill.


Patient Positioning
Summary of evidence: There was 1
level 1 study and 1 level 2 study that
compared the frequency of pneumonia
in critically ill patients assigned to semirecumbent or supine position.
 In one study (Nieuwenhoven 2006) the
target of the intervention (45 degrees
head of the bed elevation) was never
achieved

Patient Positioning
Mortality: There was no significant
difference between the groups in either
study.
 Infections: There was a significant reduction
in the incidence of pneumonia in patients in
the semi recumbent vs. supine position (p =
0.018, RR =0.22, 95% CI 0.05,0.9) in one
study (Drakulovic 1999) but no effect on
pneumonia in the other study that did not
achieve the target
intervention(Nieuwenhoven 2006)

Patient Positioning

LOS, Ventilator days: There were no
statistically significant differences
between the groups in either study.
Patient Positioning
Conclusions:
 1) Semirecument position may be
associated with a significant reduction in
pneumonia in critically ill patients.
 2) Semirecument position has no effect
on mortality, ICU length of stay or
duration of mechanical ventilation.


The residuals improve and the next day
on rounds the dietician students makes a
comment that she read about the use of
probiotics in the critically ill patient and
was wondering if we should use them in
this case.

Question #6 Does the addition of
prebiotics/probiotics/symbiotics result in
any improvement in outcome in critically ill
adult patients? (YOAN)
What are
prebiotics/probiotics/symbiotics?
‘Live microorganisms which when
administered in adequate amounts
confer a health benefit on the host’
 Endogenous bacteria in the gut
 Eg. Lactobacillus, Bifidobacterium

Why give probiotics?
Improve intestinal mucosal barrier
 Improve immune function
 Decrease load of gram – bacteria
 ?decrease diarrhea and translocation


3 groups
 Placebo
 Viable probiotics
 Non viable probiotics
Looked at immune response via IgA IgG
 Compared MODS

Canadian recommendations
1 level 1 and 10 level 2 trials
 Mortality

 No improvement
 PROPATRIA – increased mortality
Infections

LOS
 One study (Symbiotic 2000) showed
decreased LOS
others are equivical

Mechanical ventilation
 Decrease also seen in Symbiotic 2000, but
not in others
Recommendations
NO effect or overall mortality
 MAY improve ICU mortality
 NO affect on infectious complications
 MAY reduce diarrhea
