icu nutrition

Report
Nehad Mohammed Osman
Lecturer of chest diseases
Hippocrates 400 B.C.






Why do we feed ICU patients?
Which patients should we feed?
When should we start to feed them?
Which route should we feed by?
How much feed should we give?
What should the feed contain?
As many as 40% of adult patients are seriously
malnourished when admitted to the hospital.
In addition, two-thirds of all patients'
nutritional state deteriorates during their
hospital
stay.
Acute
illness
further
exacerbates patients' poor nutritional status
by increasing their metabolic rate and
impairing the allocation of nutritional
substrates.
Historically, the intensive care unit population has
been routinely malnourished. One explanation is
that nutritional issues are often not initially
explored because the traditional, more obvious
issues
involving
cardiac,
pulmonary,
or
neurological status are deemed as more critical.
Alterations in these body systems produce more
immediate body responses, such as hypotension,
chest
pain,
shortness
of
breath
or
unresponsiveness, and therefore typically garner
prompt attention. In contrast, the debilitating
effects of malnutrition may not be clinically
apparent for several days. As such, preventable
outcomes associated with malnourishment may not
be
noticed
until
patient
experiences
complications
CRITICAL COMPLICATIONS
Malnutrition in the critically ill, mechanically
ventilated patient has an adverse effect on all
physiological processes. It increases the risks for
infection and pulmonary edema. Also, nutrition
deficits decrease phosphorus needed to produce
adenosine triphosphate for cellular energy,
reduce ventilatory drive, and impair surfactant
production. These malnourished patients are
difficult to wean from the ventilator because of
muscle fatigue caused by diaphragmatic and
skeletal muscle weakness and/or reduced muscle
endurance.
PHYSIOLOGIC EFFECTS OFMALNUTRITION
Pulmonary
Decreased diaphragmatic contractility
Depressed hypoxic drive & ventilatory drive to CO2
Cardiac
Decreased contractility/response to inotrope
Ventricular dilatation
Renal
Decreased GFR
Impaired Na+ excretion
Hepatic
Altered CHO, protein & fat metabolism • Decreased protein synthesis •
Decreased drug metabolism
Impaired bilirubin excretion
Hematology •
Anaemia & coagulopathy.
Depressed T-cell functions . Impaired chemotaxis and phagocytosis
GIT
Decreased gut motility
Gut atrophy
Increase gut permeability to intestinal bacteria
few data directly compare feeding with no
feeding – two trials and one metaanalysis suggest worse outcomes in
un(der)fed patients catabolism of critical
illness causes malnutrition. malnutrition
closely associated with poor outcomes
many ICU patients are malnourished on
admission
One nutrient, protein, is especially vital in
critical illness. Decreased protein intake
associated with malnourishment decreases
serum albumin level, which leads to a
decreased intravascular and intracapillary
oncotic pressure. This decreased pressure
causes fluid to leak from the intravascular
space into the interstitial space, a condition
referred to as third spacing, which causes
edema.


Ultimately,
malnutrition
increases
patient
mortality and hospital cost by prolonging a
patient's hospital stay.
Critically ill patients who receive prolonged
mechanical
ventilation
without
nutritional
support have a 20% to 40% increased risk of
developing
ventilator-associated
pneumonia
(VAP) compared to those who are fed enterally
within 48 hours of intubation. VAP is associated
with a 20% to 25% increased relative mortality
and an increased hospital stay of at least four
days.






Increased morbidity and mortality
Prolonged hospital stay
Impaired tissue function and wound healing
Defective
muscle
function,
reduced
respiratory and cardiac function
Immuno-suppression, increased risk of
infection
CIPs lose around 2%/day muscle protein


treat existing malnutrition
minimise (but not prevent) the wasting of
lean body mass that accompanies critical
illness
important to identify existing malnutrition
clinical evaluation is better than tests
History
1. Weight change (>5% of usual body weight in 3 weeks or >10% in
3 months).
2. Changes in food intake.
3. Gastrointestinal symptoms.
4. Functional impairment.
Physical Examination
1. Loss of subcutaneous fat – especially in chest and triceps (body
mass index <20).
2. Muscle wasting – especially at temporal region, deltoids and
gluteals.
3. Oedema.
4. Ascites.
which patients can safely be left to resume
feeding themselves?
14 days’ starvation - dangerous depletion of
lean body mass
mortality rises in ICU patients with a second week
of severe under-feeding
5 days without feed increases infections but not
mortality
one view is therefore that 5-7 days is the limit
however
ACCEPT study fed all patients not likely to eat
within 24 hours
one meta-analysis suggests reduced infections if
patients are fed within 48 hours
one meta-analysis of early TPN versus delayed EN
found reduced mortality with early feeding


all malnourished patients
all patients who are unlikely to regain
normal oral intake within either 2 or 5-7
days depending on your view



without undue delay once the patient is
stable
this will usually be within 48 hours of ICU
admission
ACCEPT study aimed to start within 24 hours of
ICU admission


Studies suggest that initiating nutritional support
within 24 to 48 hours of intubation helps maintain
lean body mass and immune function, thereby
improving clinical outcomes, lowering infection rates
and reducing hospital length of stay.
Starting enteral nutrition near the beginning of an
acute illness has several benefits. This type of
nutrition improves immune function and augments
the cellular antioxidant system. There is also a
decrease in the body's hypermetabolic response to
tissue injury. Other advantages include better
nitrogen balance and improved wound healing. For
this reason, it is imperative the nurse requests a
nutrition consult within 24 to 48 hours following
endotracheal intubation

enteral feeding is claimed to be superior
because
 it prevents gut mucosal atrophy
 it reduces bacterial translocation and multi-organ
failure
 lipid contained in TPN appears to be immunosuppressive



EN preferred for majority on pragmatic
grounds alone
TPN obviously necessary for some
if there is serious doubt that EN can be
established in 2 (or 5, 7…) days
 commence TPN
 maintain at least minimal EN
 keep trying to establish EN

does EN reduce infections?
pancreatitis - probably
abdominal trauma - probably (2 trials of 3)
head injury - evenly balanced
other conditions – no clear conclusion
Lipman reviewed 31 trials and found no
consistent effect
◦ meta-analysis by Heyland et al found reduced
infections
◦
◦
◦
◦
◦

EN is definitely a risk factor for VAP


Decisions
on
route,
content,
and
management of nutritional support are best
made by multidisciplinary nutrition teams
enteral feeding is
◦ cheaper
◦ easier
◦ and therefore preferable in most cases

parenteral feeding is obviously necessary in
some





ETF can be used in unconscious patients, those with
swallowing disorders, and those with partial intestinal failure.
It may be appropriate in some cases of anorexia nervosa.
Early post pyloric ETF is generally safe and effective in
postoperative patients, even if there is apparent ileus
Early ETF after major gastrointestinal surgery reduces
infections and shortens length of stay
In all post surgical patients not tolerating oral intake, ETF
should be considered within 1–2 days of surgery in the
severely malnourished, 3–5 days of surgery in the moderately
malnourished, and within seven days of surgery in the
normally or over nourished.
If there are specific contraindications to ETF, parenteral
feeding should be considered. If patients are taking .50% of
estimated nutritional requirements, it may be appropriate to
delay instigation of ETF.



Fine bore (5–8 French gauge) nasogastric (NG)
tubes should be used for ETF unless there is a
need for repeated gastric aspiration or
administration of high viscosity feeds/drugs via
the tube. Most fibre enriched feeds can be given
via these fine bore tubes
Long term NG and NJ tubes should usually be
changed every 4–6 weeks swapping them to the
other nostril
Gastrostomy or jejunostomy feeding should be
considered whenever patients are likely to require
ETF for more than 4–6 weeks and there is some
evidence that these routes should be considered
at 14 days
ENTERAL FEEDING RESIDUAL VOLUMES
Residual volumes are routinely checked as a way to
assess tube-feeding tolerance and help to assess a
patient's risk for aspiration. Although checking
residual volume is a common clinical practice, there
is no data correlating a specific residual volume with
increased aspiration events. The single best measure
a nurse can do to prevent aspiration of enteral
feedings and therefore reduce the risk of VAP is to
keep the patient's head of bed elevated at least 30
degrees.
The
American
Gastroenterological
Association recommends elevating the head of bed to
a minimum of 30 to 45 degrees to reduce the risk of
microaspiration.


Gastric residual volumes greater than 200 ml to 250 ml
are generally considered high in critically ill patients
with an artificial airway in place. It is interesting to note
that the combined secretion of saliva and gastric fluids
may total up to 188 ml/hr, which brings one to
question whether a tube feeding residual of 250 ml is
really an accurate reflection of poor absorption. It is not
recommended to automatically stop a tube feeding for
an isolated high gastric residual volume. A residual
recheck should be done one hour before tube feedings
are held. Though the gastric residual is a factor in
aspiration, ongoing studies contend there is no
consistent relationship between aspiration and gastric
residual volumes. However, aspiration does occur
significantly more often when volumes are high.
Complication

Nasal damage, intracranial insertion,
pharyngeal/oesophageal pouch perforation,
bronchial placement, variceal bleeding
 PEG/PEJ insertions
Bleeding, intestinal/colonic perforation
 Post insertion trauma
Discomfort, erosions,
fistulae, and
strictures
 Displacement
Tube falls out, bronchial
administration of feed
 Reflux
Oesophagitis, aspiration
 GI intolerance
Nausea, bloating, pain,
diarrhoea
 Metabolic
Refeeding syndrome, hyperglycaemia,
fluid overload, electrolyte disturbance
 PEG, percutaneous endoscopic gastrostomy; PEJ, percutaneous
endoscopic jejunostomy; GI, gastrointestinal.

Type
Insertion
Complication
Severity
Definition
Treatment
Vomiting
(occurrence)
1-4+ times/12 hrs
Abdominal Distension and/or
cramping or tenderness (if
detectabl
Mild
Hx and/or physical evidence
Check for constipation;
Maintain TF infusion rate;
Reexamine in 6 hrs if
indicators remain mild,
maintain TF infusion rate
Moderate
Hx and/or physical evidence
Order abdominal series X-rays
to assess for small bowel
obstruction. If SB, notify
primary team. Stop TF
infusion. Replace existing NG
Catheter
Moderate >24 hr or Severe
Hx and/or physical evidence
Stop TF infusion. Consider
TPN
Place NG to suction, check
function. Check existing NG
function. ▼TF infusion rate by
50%; Notify primary team
Table: GI Complications Associated with Enteral Feedings
(Adults)
Diarrhea
Mild 1-2 x per shift or Maintain TF infusion
100-200cc/12
rate. Evaluate for
hrs
pharmaceutical
causes. Increase to
goal
Moderate
Severe
3-4 x per shift or
200-300cc/12
hrs
Maintain TF infusion
rate. Re-examine in
6 hrs. if mild or
moderate, continue
to goal rate;
Evaluate
medications
▼TF infusion rate by
50%. Order stool
studies. Evaluate
medications. Give
antidiarrhea meds.
Table: GI Complications Associated with Enteral Feedings (Adults)
High NG output
with post-pyloric
Feeding Tube
Placemen
(measured)
NG output >
800cc (with
post-pyloric FT
placement)
Hold tube
feedings Check
Xray to verify
post-pyloric
feeding tube
placement
High Gastric
Residuals with
gastric Feeding
Tube placement
(measured)
Hold tube
feedings for
residuals greater
than 200cc
Start prokinetic
agent; Head of
bed elevated 30
degrees when
possible. Check
for constipation
Constipation
(measured)
Less than 2
bowel
movements per
week
Stool softeners
and water
boluses



use fibre-containing feed
avoid drugs containing sorbitol and Mg
exclude and treat
 Clostridium difficile infection
 faecal impaction

consider
 malabsorption (pancreatic enzymes, elemental
feed)
 lactose intolerance (lactose-free feed)
 using loperamide
WHEN TO USE TPN
Parenteral nutrition should only be used in
patients with an inaccessible or nonfunctional
gastrointestinal tract. Some of the most common
reasons are due to a massive gastrointestinal
bleed, acute abdomen, bowel obstruction/ileus,
intractable vomiting or diarrhea, or prolonged
NPO status postoperatively—greater than 7 to 10
days. The potential for transitioning to enteral
feedings should be reevaluated daily in patients
on parenteral nutrition. The perfect time for such
a reevaluation is during interdisciplinary ICU
morning rounds


Early initiation of nutritional support is integral to
the recovery of a critical illness, and evidence
supports that enteral nutrition is both efficient
and effective in providing necessary nutrition,
particularly in the mechanically ventilated
population. The key to obtaining nutrition in a
timely manner is interdisciplinary collaboration
among the critical-care physician, critical-care
nurse, and nutritionist. This collaboration is best
achieved through daily interdisciplinary rounds
on all critically ill patients so that all team
members have input into the patient's plan of
care

overfeeding is
◦ useless - upper limit to amounts of protein and
energy that can be used
◦ dangerous





hyperglycaemia and increased infection
uraemia
hypercarbia and failure to wean
hyperlipidaemia
hepatic steatosis
underfeeding is also associated with malnutrition
and worse outcomes

carbohydrate
 EN: oligo- and polysaccharides
 PN: concentrated glucose

lipid
 EN: long and medium chain triglycerides
 PN: soya bean oil, glycerol, egg phosphatides

nitrogen
 EN: intact proteins
 PN: crystalline amino acid solutions


water and electrolytes
micronutrients

glutamine?

selenium?

immunonutrition?


EVALUATING NUTRITIONAL STATUS Although no
single indicator provides an accurate depiction of
a patient's nutritional status, parameters
commonly used in all patients requiring a
nutrition consult are body mass index (BMI),
albumin/prealbumin level, nitrogen balance, and
serum levels of trace elements
An initial nutritional assessment includes a
physical assessment and medical history. BMI is a
common anthropometric measure of nutritional
status used to diagnose obesity and under
nutrition associated with clinical conditions.


A common method of measuring a patient's protein status is
the serum albumin level. Studies show that critically ill
patients receiving long-term ventilation have low albumin
levels during their hospitalization. These low levels are likely
a reflection of both nutritional status and prolonged
physiological stress associated with illness and/or ventilator
weaning .
Many practitioners, however, prefer to measure the
prealbumin level, because albumin changes in response to
outside factors such as sepsis and surgery. Serum levels of
prealbumin have a half-life of three to five days compared
with 21 days for albumin. The rapid turnover of prealbumin is
a reflection of its increased sensitivity to change in a body's
protein status, therefore making it a more immediate
indicator of physiological stress and nutrition status.
Decreased protein intake depletes the body's nitrogen
reserve, which is manifested as a negative nitrogen balance. A
patient's nitrogen balance is calculated by measuring the
amount of urea nitrogen excreted in urine over 24 hours and
utilizing a standard formula, and then comparing that to the
amount of protein ingested during that same 24-hour period.
N Balance(g)=(protien intake (g)/6.25)-(UUN+4)
4=Daily nitrogen loss in grams ,other than UUN.BUT if UUN
is>30g/24h,add 6 =Daily nitrogen loss in grams.
 Serum levels of the trace elements of magnesium and
phosphorus are biochemical indicators routinely used by
clinicians to monitor nutritional status in critically ill patients.
Magnesium deficiencies can be associated with acute
diarrhea, a potential side effect of enteral feedings.
Magnesium and phosphorus are important in energy
synthesis and wound healing. Furthermore, abnormal levels
of either of these electrolytes can cause cardiac, neurological,
and neuromuscular disorders.

Step1: Weight Calculation
Ideal Body Weight (IBW) will be used for nutritional estimates
for the majority of patients
Use Lean Body Weight (LBW) if pt obese or edematous
a. IBW=50 kg + or 45 kg for females (2.3 kg for each inch over
60")
b. Lean Body Weight=IBW + 0.4 (Actual weight - IBW)
Step 2: Non-protein Energy calculations
25-30 kcal/kg {aim for 25Kcals/kg}
65-70% as carbohydrate and 25-30% as fat
Consider 20 % calories reduction if pt is sedated or paralyzed
Step 3: Protein requirement calculations
1.5 – 1.8 g/kg/d utilizing IBW for all patients
Severe Hepatic Encephalopathy: protein restrict to 0.6 g/kg /d
Renal failure:
i. If patient on RRT, full protein supplementation at 1.5 –2.5 g/kg/d
should be instituted.
ii. If not on RRT, consider reducing initial protein intake to 1 – 1.3
g/kg/d and follow BUN daily.
iii. If patient oliguric, start at ≤ 0.6 g/kg/d and follow daily BUN
Step 4: Micronutrient calculation
Daily
Daily
Daily
Daily
Electrolyte requirement
Vitamins requirement
Trace Element requirement
requirement of fluid losses from GIT
(See the following table)
Sodium
1.0 mmol/kg/day

Potassium
Phosphate
1.0 mmol/kg/day Dependent on renal function
0.2 mmol/kg/day Dependent on renal function

Magnesium
0.3 mmol/kg/day Dependent on renal function
Calcium
Vitamins
0.1 mmol/kg/day
groups B daily.B12, Folate, A, D, E, K weekly Trace elements
as required





1.
2.
3.
Replacement solutions
Urine
1.½ Normal saline ± KCl 10 ml/L
2. Nasogastric/ileostomy 2. ½ Normal saline ± KCl 10 ml/L
3. Pancreatic/biliary fistulae
3. Ringer Lactate or Acetate
Canadian Critical Care Clinical Practice Guidelines Committee. Canadian clinical
practice guidelines for nutrition support in mechanically ventilated, critically ill
adult patients. J. of Parenteral Enteral Nutr. 27: 355–73
1.Fluid
30-40 ml/kg BW
2. Energy
1. Total Energy expenditure 2. Calorie/weight : 25-35
kcal/kg/day
3. Indirect calorimetry
3. Protein Normal prot : 0.8 g/kg/d HD. CVVHD : 1.1 –
1.4 g/kg/d Sepsis/trauma : 1.2 – 2.0 g/kg/d Severe
burns : 2.5 – 4.0 g/kg/d






energy - 25 kCal/kg/day (ACCP)
NUTRITIONAL REQUIREMENTS
BEE classically is estimated by the Harris- Benedict
equation:
For men, BEE = 66.5 + (13.75 x kg) + (5.003 x cm) (6.775 x age)
For women, B.E.E. = 655.1 + (9.563 x kg) + (1.850 x
cm) - (4.676 x age)** BEE - Basal Energy Expenditure
Total Energy Expenditure ( TEE) = BEE x Injury Factor
Injury Factor
 Mild illness 1 – 1.25 eg. minor op 1.2
 Moderate illness 1.25 – 1.5 eg skeletal
trauma 1.35
 Severe illness 1.5 – 1.75 eg major sepsis 1.60
 Estimated Total Energy Requirement = BEE x
Activity Factor x Injury Factor










INDIRECT CALORIMETRY
Most accurate.
Portable bedside system measuring of EE and resp
quotient by measuring and analysing the O2 consumed (
VO2) and the CO2 expired ( VCO2)
REE(Kcal/24hr)=(3.9ΧVo2)+(1.1 Χ Vco2)-61
Respiratory Quotient = CO2 production/O2consumption
RQ Interpretation> 1.00 overfeeding
0.9 – 1.00 CHO oxidation
0.8 – 0.9 Mixed nutrients oxidation
0.7 – 0.8 Fat and protein oxidation
Limitations: expensive equipment , need trained
personnel,O2 sensor is not reliable at inspired O2 levels
above 50% so it is unreliable in pts with respiratory failure
who require inhaled O2 concentrations above 50%.

nitrogen
◦
◦
◦
◦
no benefit from measuring nitrogen balance
nitrogen 0.15-0.2 g/kg/day
protein 1-1.25 g/kg/day
severely hypercatabolic patients (eg burns) may
receive up to 0.3 g nitrogen/kg/day





Add 2-2.5ml/kg/day of fluid for each
degree of temperature
Account for excess fluid losses
Adequate
electrolytes,
micronutrients,
vitamins
Avoid overfeeding
Obesity: feed to BMR, add stress factor only
if severe i.e. burns/trauma

Carbohydrate, CHO
Main source of energy, 60% of total energy requirement.
2-3 g/Kg/day 1 g CHO = 4 Kcal
Fat
30-40% of caloric intake.
1.5-2 g/Kg/day 1 g Fat = 9 Kcal
 Protein
Not a major energy source. Provide essential & non essential
amino acids for protein synthesis. Use as energy substrate (CHO
@ Fat precursor) in excess.
1-1.5 g/Kg/day
1 g Protein = 4 Kcal.
1 g N2 = 6.25 g Protein.

Enteral feeding should be started early within the first 24–48
hours following admission. The feedings should be advanced
toward goal over the next 48–72 hours
Efforts to provide >50% to 65% of goal calories should be made
to achieve the clinical benefit of EN over the first week of
hospitalization.
If unable to meet energy requirements (100% of target goal
calories) after 7 days by the enteral route alone, consider
initiating supplemental PN
PN should not be initiated in the immediate postoperative
period, but should be delayed for 5-7 days
If there is evidence of protein-calorie malnutrition at admission
and EN is not feasible, it is appropriate to initiate PN as soon as
possible following admission and adequate resuscitation
The use of additional modular protein supplements is a
common practice, as standard enteral formulations tend to have a
high non protein calorie : nitrogen ratio
In the setting of hemodynamic compromise (patients requiring
significant
hemodynamic
support,
including
high-dose
catecholamine agents, alone or in combination with large volume
fluid or blood product resuscitation to maintain cellular perfusion),
EN should be withheld until the patient is fully resuscitated and/or
stable
In patients with body mass index (BMI) <30, protein requirements
should be in the range of 1.2–2.0 g/kg actual body weight per day,
and may likely be even higher in patients with In the critically ill
obese patient, permissive underfeeding or hypocaloric feeding with
EN is recommended. For all classes of obesity where BMI is >30,
the goal of the EN regimen should not exceed 60% to 70% of target
energy requirements or 11–14 kcal/kg actual body weight/day (or
22–25 kcal/kg ideal body weight/day)
Protein should be provided in a range ≥ 2.0 g/kg ideal body
weight/day for class I and class II patients (BMI 30–40), ≥ 2.5 g/kg
ideal body weight/day for class III (BMI ≥40) burn or multiple
trauma
Use of chlorhexidine mouthwash twice a day should be
considered to reduce risk of ventilator-associated pneumonia.
Patients with acute respiratory distress syndrome and severe
acute lung injury should be placed on an enteral formulation
characterized by an antiinflammatory lipid profile (i.e., omega-3
fish oils, borage oil) and antioxidants
Specialty high-lipid low-carbohydrate formulations designed to
manipulate the respiratory quotient and reduce CO2 production
ARE NOT RECOMMENDED for routine use in ICU patients with acute
respiratory failure.
Patients receiving hemodialysis or continuous renal replacement
therapy should receive increased protein, up to a maximum of 2.5
g/kg/day
Protein should not be restricted in patients with renal
insufficiency as a means to avoid or delay initiation of dialysis
therapy.
Standard enteral formulations should be used in ICU patients
with acute and chronic liver disease. The branched chain amino
acid formulations should be reserved for the rare encephalopathic
patient who is refractory to standard therapy with luminal-acting
antibiotics and lactulose
Patients with mild to moderate acute pancreatitis do not require nutrition
support therapy (unless an unexpected complication develops or there is
failure to advance to oral diet within 7 days)
Patients with severe acute pancreatitis may be fed enterally by the gastric
or jejunal route
In acute pancreatitis change the content of the EN delivered from intact
protein to small peptides, and long-chain fatty acids to medium-chain
triglycerides or a nearly fat
Guidelines for the provision and assessment of nutrition support
therapy in the adult critically ill patient: Society of Critical Care
Medicine and American Society for Parenteral and Enteral Nutrition
Crit Care Med 2009 Vol. 37, No. 5
HOW TO CALCULATE TPN ?
Steps Example:
A 56 yr, 1.75 m tall, 70 kg man
1. Determine the protein 70 kg x 1.5g/kg/d = 105 g/d ( = requirement
16.8g N)
2. 2. Determine the total caloric Using Harris Benedict equation: requirement
BEE = 66 + ( 13.7 x 70kg) + ( 15 x 175cm) – (6.8 x 56 yr) = 1519
kcal/day ( round off to 1500 kcal/day) TEE = BEE x IF = 1500 x 1.3 =
1950 kcal/day
3. Divide the total caloric If ratio 60:40 requirement between two energy
1950 x 0.6 : 1950 x 0.4 = 1170 : substrate, CHO : fat ( 60:40 or 780
70:30
4. Determine calorie : nitrogen ratio 1950 : 16.8 = 116 : 1
5. Calculate amount of CHO needed If using 70% dextrose solution ( 100 ml
provide 70 g CHO x 3.4 kcal/g = 238 kcal) 1170 kcal / 238 kcal x 100 mls =
492 mls ~ 500 mls
6. Calculate amount of fat emulsion If using 20% intralipid ( provides 2needed
kcal/ml) 780 kcal divide into 2 kcal/ml = 390 ml
7. Estimate fluid requirement 40 ml/kg/day x 70 kg = 2800 ml/d Therefore :
2800 – ( 500 + 390) = 1910 ml ( of water to be added to meet fluid
requirement )
.8
8.Order electrolytes: Na+, K+,Mg2+, Ca, phosphorus, acetate and
chloride
9. Order multivitamin, trace minerals and vitamin K if needed
10. Determine flow rates : volume / 2800 ml / 24H = 117 ml/H24h



catheter-related sepsis
Catheter Malposition pneumothorax hydrothorax
Arterial puncture
Metabolic
Hyperglycaemia Hypoglycemia if TPN is abruptly stopped
Increased CO2 production & increased O2 consumption if
infusion rates beyond 4 ml/kg/mt. Hypomagnesemia,
hypophosphatemia if not supplemented
hyperchloraemic metabolic acidosis

electrolyte imbalance - low Pi, K, Mg

refeeding syndrome

abnormal LFTs

deficiency of thiamine, vit K, folate
Fatty liver


Clinical studies have shown that ICU patients receiving parenteral
nutrition have demonstrated a higher incidence of metabolic and
infectious complications than those patients receiving enteral
nutrition.
Common
metabolic
complications
include
hyperglycemia, hypoglycemia, and refeeding syndrome — the
body suddenly shifts from fat metabolism to carbohydrate
metabolism. This shift causes a surge in insulin levels, which in
turn leads to an increase in the cellular uptake of phosphorus,
resulting in hypophosphatemia. Primary symptoms of
hypophosphatemia are muscle weakness and wasting and
general fatigue, all of which are barriers to successful ventilator
weaning and healing.
Acute cholecystitis is a common complication of parenteral
nutrition, related to the complete lack of usage of the
gastrointestinal tract resulting in biliary stasis in the gall bladder.
Total parenteral nutrition must infuse through a central venous
catheter, and a bacterial infection of that catheter is a serious
and potentially life-threatening risk.

glutamine?

selenium?

immunonutrition?




primary fuel for enterocytes, lymphocytes
and neutrophils; also involved in signal
transduction and gene expression
massive release from skeletal muscle
during critical illness
may then become ‘conditionally essential’
is not contained in most TPN preparations




reduces villus atrophy in animals and
humans
reduced pneumonia and bacteraemia in
two studies - multiple trauma, sepsis
one much larger study (unselected ICU
patients) showed no effect
difficult to give adequate dose enterally




Liverpool study in ICU showed reduction in
late mortality
London study of all hospital TPN patients
showed no benefit
French trauma study showed reduced
infection but no mortality effect
German ICU study improved late survival in
patients fed for more than 9 days


glutamine
becomes
conditionally
essential in critical illness and is not
given in standard TPN
parenteral supplementation appears to
be beneficial in patients requiring TPN
for many days




regulates free-radical scavenging systems
low levels common in ICU patients
several small studies inconclusive but
suggest benefit
one large, flawed recent study showed nonsignificant mortality benefit

omega-3 fatty acids
 produce less inflammatory eicosanoids

arginine
 nitric oxide precursor
 enhances cell-mediated immunity in animals

nucleotides
 DNA/RNA precursors
 deficiency suppresses cell-mediated immunity




few studies in ICU populations
some found reduced infection in elective
surgery
one unblinded study has shown reduced
mortality in unselected ICU patients;
benefit in least ill (CCM 2000; 28:643)
another showed increased mortality on
re-analysis which barely failed to reach
statistical significance (CCM 1995;
23:436)

first meta-analysis (Ann Surg 1999; 229:
467)
 no effect on pneumonia
 reduced other infections and length of hospital stay
 increased mortality only just missing statistical
significance
 did not censor for death

second meta-analysis (CCM 1999; 27:2799)
 reduced infection
 reduced length of ventilation and hospital stay
 no effect on mortality

third meta-analysis (JAMA 2001; 286:944)
 benefit in elective surgery
 increased mortality in ICU patients with sepsis

large Italian RCT (ICM 2003; 29:834)
 compared enteral immunonutrition with TPN
 stopped early because interim analysis showed
increased mortality in septic patients
 44.4% vs 14.3%; p=0.039
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Enumerate the Effects of Malnutrition?
Mention the Consequences of malnutrition?
When should we start to feed patient admitted to ICU
?
Mention the complications of enteral tube feeding ?
How to mange diarrhoea in COPD patient on mechanical
ventilation received entral feeding through nasogastric tube ?
WHEN to use TPN ?
What should the feed contain in ICU ?
HOW to calculate TPN in60 yr, 1.75 m tall, 80 kg female ?
Mention the Limitations of indirect calorimetry ?
Mention the complications of TPN ?

similar documents