- Click here for explanation of classification scheme.

1. To determine the energy requirement for mechanically ventilated, critically ill patients using the nutritional status.

Definitions

1. Steady state
2. Measured energy expenditure (MEE): a single 40-min measure taken on day 1
3. Total energy requirement (TER): “MEE” plus 5% activity factor plus 15% day-to-day variability
4. UF: subject’s actual average intake <90% of TEE
5. AF: subject’s actual average intake within±10% of TEE
6. OF: subject’s actual average intake >110% of TEE.

1. Understand and give written consent
2. Patients that were hemodynamically stable, not comatose, and requiring at least 7 days of mechanical ventilation.

1. Refusal to consent
2. Not meeting inclusion criteria
3. If they received a fraction of inspired oxygen >60% at the time of IC measure
4. Oliguric patients

ANTHROPOMETRIC

• Ht measured? yes
• Wt measured? yes
• Fat-free mass measured? Yes; TSK and mid-arm circumference

CLINICAL

• Monitored heart rate? Likely
• Body temperature? Likely
• Medications administered? Not reported

Resting energy expenditure

• IC type: Deltatrac II MBM-200
• Equipment of Calibration: Yes
• Coefficient of variation using std gases: Not specified
• Rest before measure (state length of time rested if available): Bedridden
• Measurement length: 40 min
• Steady state: Not specified
• Fasting length: were without intermittent caloric intake for at least 4 hrs prior to IC; Continuous enteral or parenteral were not stopped
• Exercise restrictions XX hr prior to test? not applicable
• Room temp: ICU Taichung Veterans hospital
• No. of measures within the measurement period: 1
• Were some measures eliminated? Not specified
• Were a set of measurements averaged? No
• Coefficient of variation in subjects measures? Not specified
• Training of measurer? Yes
• Subject training of measuring process? Not applicable

DIETARY

Three types: enteral nutrition, TPN, or combined enteral nutrition plus TPN. RNs and dietitians routinely recorded infusion nutrient intake.

2 nutritional indices used:

• Maastricht Index (MI):
  MI=20.68- [0.24 X albumin (g/l)] – [19.21 X prealbumin (gram/l)] – [1.86 X lymphocytes (10⁹/Liter)] –(0.04 X % ideal body weight).
  MI >0 were considered malnourished
• Nutritional Risk Index (NRI)=
  [15.9 X plasma albumin (gram/deciliter) + 41.7 X (present weight/usual weight).

NRI

• >100 indicates not malnourished
• 97.5-100 indicates mildly malnourished
• 83.5 to <97.5 indicates moderately malnourished.
• <83.5 indicates severely malnourished

Outcome(s) and other measures

1. Measured REE [(VO₂ l/min), VCO₂ (l/min; ml/kg/min), RQ, ventilation (l/min)]
2. Nutrition outcomes: Fdg route, energy expenditure, Nutrient intake (kcal), CHO, (grams/d and % of total energy) , Protein (grams/d and % total energy), and Fat (grams/d and % total energy)
3. Clinical outcomes: APAHCE II score, hospital stay length, ICU stay length, ventilator dependence length
4. Biochemical measures: albumin, prealbumin, TLC, CHI, and N-balance
5. Urinalysis: urine urea nitrogen (UUN), creatinine
6. Independent variables of weight, height, age, BMI, MAC, and fat-free mass, fat mass.

Blinding used: No

• N=118 patients entered study;
• 54 completed (40 men, 14 women)
• (46% of patients entering)
• Age range, yr: 23-89

Most common diagnoses: GI disorders, malignant neoplasm, and pneumonia.

Statistical tests

1-way ANOVA; Student t test to compare difference between day 1 and day 7 within a group; Pearson correlation coefficient; P <0.05 significant; Means ±SD.

ANTHROPOMETRIC

• UF (n=15; 14 M; 1 F)

Day 1	Mean±SD
Age, y	61.9±14.6
Wt, kg	64.5±11.1
BMI	23.7±3.6
TSK, mm	11.6±5.8
MAC, mm	282.3±33.4
MAMC, mm	245.8±26.1

• AF (n=20; 17 M; 3 F)

Day 1	Mean±SD
Age, y	68.0±14.1
Wt, kg	63.1±13.0
BMI	23.8±4.2
TSK, mm	11.5±5.1
MAC, mm	271.5±38.0
MAMC, mm	235.5±30.7

• OF (n=20; 17 M; 3 F)

Day 1	Mean±SD
Age, y	72.2±2.1
Wt, kg	52.7±7.9
BMI	21.1±4.0
TSK, mm	10.8±5.4
MAC, mm	245.9±37.9
MAMC, mm	212.0±29.5

There were no statistically significant age, ht wt differences at admission.

INDIRECT CALORIMETRY

• UF (n=15; 14 M; 1 F)

Mean±SD
RQ	0.91±0.19
RQ, 98%	0.53-1.29
MEE, kcal/d	1878.9±359.5
TEE, kcal/d	2254.7±431.3
TEE (kcal/kg/day)	35.7±7.3

• AF (n=20; 17 M; 3 F)

	Mean±SD
RQ	0.97±0.12
RQ, 98%	0.73-1.21
MEE, kcal/d	1572.0±256.0
TER, kcal/d	1886.4±307.2
TER (kcal/kg/day)	30.6±6.9

• OF (n=20; 17 M; 3 F)

	Mean±SD
RQ	1.16±0.32
RQ, 98%	0.52-1.80
MEE, kcal/d	12752±194.9
TER, kcal/d	1526.9±233.8
TER (kcal/kg/day)	30.6±7.0

OF pt had a mean RQ value >1

[Analyst note: assuming normality, 98% of pt had RQ from 0.52-1.80 in the OF group].

NUTRITION FEEDING OUTCOMES

• UF patients were more likely to be receiving combined nutrition (n=8), while AF and OF pt were more likely to be receiving enteral and combined nutrition (n=7 each). UF pt had the highest MEE and total energy requirement.
• UF patients received, on average, only 68.3% of energy requirements, while OF pt received up to 136.5% of their estimated total energy requirements.
• OF pt had a higher enrgy intake attributed to CHO and fat, but not protein; No significant difference in % energy intake from CHO, protein, and fat.
• OF pt had a significantly higher CHO intake than other 2 group when expressed per kg body wt; but no significant different in total CHO intake among 3 groups.
• UF pt had a CHO intake >60% of total calories.
• NO significant difference in group mean protein intake among 3 groups.
• 5 UF pt, 6 AF pt, and 2 OF pt had a protein intake <0.8 g/kg/day. The % of calories from fat for all 3 groups <30%.

NUTRITIONAL STATUS ASSESSMENT OUTCOMES

• Mean current weight did not significantly change between Day 1 and Day 7.
• UF pt showed a significant reduction in MAC, MAMC, and arm muscle areas when compared with day 1.
• AF and OF pt showed slight increases (statistically insignificant) in weight, BMI and TSF.
• Pts in all 3 gropus showed no significant changes in albumin, prealbumin, and TLC by day 7.
• Mean % CHI was <90% with no significant changes compared to day 7.
• All 3 groups were in negative N-balance on admission and only AF pt showed a positive N-balance on day 7.
• All 3 group patients were malnourished when admitted using MI and there were no significant differenced among groups on day 7.
• All 3 group patients were considered severely malnourished using NRI and only AF pt had a significantly higher NRI value at day 7 than at day 1.

CLINICAL OUTCOMES

• Severity of disease (APACHEII score) was not significantly different among the 3 groups at admission and 7 days after.
• No statistically significant differences among groups for length of ventilator dependency, ICU stay and hospital stay.
• Length of ventilator dependency was significantly positively correlated (r=0.494, P=-0.3) on in the AF group.
• Length of ICU stay was significantly positively (r=0.525, P=0.02) correlated with CHO intake in AF group.

As stated by the author in body of report

Using single and multiple parameters to assess nutritional status results showed our critically ill patients were in a severely malnourished state.” [and] “Driver & LeBrun, 1980 found that nutritional support was inadequate in 3 out of 26 pt ”

“Mean RQ value in present AF and OF pt was close to or >1 [and] OF group received significantly higher CHO amouts and correlated with ICU stay length. Thus, when there is a need for increasing energy intake, the enrgy source should be carefully chosen to avoid giving excess CHO calories.”

“Patients had a mean protein intake of ~1.1 g/kg per day, obviously inadequate for critically ill population to achieve a positive N-balance . . . [However,] the severity, duration and influence of N-balance on patients’ clinical outcome still cannot be assessed from the data we collected. Pt in UF group showed decreases in MAC, MAMC, and arm muscle area at day 7, indicating pt in a catabolic state and losing LBM.

“Limitations of our study are sample size and 7-day length of observation [and] slight wt increases could be due to pt with mechanical ventilation having greater fluid retention, not breathing spontaneously.

“Providing at least 120% of RMR seemed adequate to meet caloric energy needs of hemodynamically stable, mechanically ventilated, critically ill patients.”

Industry:
University/Hospital:	Taichung Veterans General Hospital (Tiawon)

Strengths

“Study protocol completely described, and included nutrition parameters.”

“Used two validated nutrition risk tools”

Generalizability/Weaknesses

“Generalizability to critically ill patients with respiratory, GI, malignant neoplasms, infection, and trauma.” Unable to generalize for burn patients as only one patient in the underfed group was diagnosed as “burn patient”

“Study biases include 54% drop-out rate and patient characteristics of drop-outs not reported.”

Limitations as per researcher: sample size unable to detect a beta-error and length of observation may not be long enough to assess some biochemical and clinical nutrition markers.

Intervening variables not discussed were medication usage (i.e., sedation, chemical paralysis), and fever which may affect IC measure technique and nutrition outcome interpretations; Also note that the UF group did NOT include any pt with infection (i.e., groups may not be comparable due to intervening variable)

Analyst note: Interesting that the “overfed” group had the lowest BMI range of 17.1-25.1] which would be interesting if they had used Harris-Benedict and stress factor if this would have occurred?]