Table 2.
Feasibility of outcome measures, planned versus achieved measurements
| Outcome measure | Target (%) | Achieved (%) | Comment | Control (n = 4) Results as range |
L-EAA (n = 4) Results as range |
|
|---|---|---|---|---|---|---|
| Patients recruited | > 30 | 9.5% patients recruited | Lower than anticipated | – | – | |
| L-EAA supplement | > 70 | 73% doses given | Unable to give due to GI intolerance | – | – | |
| Inflammatory markers and cytokines | > 90 | 100% samples taken | All required samples were taken | CRP (mg/L) | 2–312 | 42.7–262 |
| Serum albumin (g/L) | 22–30 | 29–39 | ||||
| IL-6 (pg/mL) | 11.4–141 | 9–78.5 | ||||
| IL-10 (pg/mL) | 0–137 | 0–2100 | ||||
| Urine samples (u-urea, 3-MH) | > 80 | 81% samples taken |
CRRT expected in some patients hence > 80% planned No misplaced samples |
Urinary urea (mmol/24 h) | 55–269 | 51–382 |
| 3-MH (μmol/24 h) | 174–616 | 144–660 | ||||
| Muscle depth via ultrasound (sum of three sites, planned measurement on alternate days) | > 90 | 50% measurements completed |
Shorter LOS than anticipated Fewer measurements recommended, i.e. days 1, 7, 10 |
Muscle depth (cm) | 5.34–12.36 | 4.43–11.93 |
| Protein turnover study | > 80 | 31% studies completed |
Complex, time-consuming Required 3 staff members for Douglas bag breath collection method and blood sampling. Simpler technique required, whole body vs muscle protein turnover |
Protein turnover (g/24 h) | 0 | −3.9 to −1.73 |
| Nitrogen balance (PENG, g/day) | > 80 | 81% calculated | CRRT affecting urine sampling, urinary urea | − 10.6 to 7.4 | − 7.95 to 11 | |
| Nitrogen balance (Deacon, g/day) | > 80 | 81% calculated | CRRT affecting urine sampling, urinary urea | − 6.2 to 7.4 | − 3.3 to 11.2 | |
| Katz and Barthel indices | > 90 | 100% tested | Poor tests in this setting with substantial floor effect | 0 | 0 | |
| MRC sum score | > 90 | 0% completed | No patient passed initial MRC screening questions (8/10 presented with traumatic brain injury) | – | – | |
CRP C-reactive protein, IL-6 interleukin 6, IL-10 interleukin 10, L-EAA leucine-enriched essential amino acid, GI gastrointestinal, CRRT chronic renal replacement therapy, 3-MH 3-methylhistidine, LOS length of stay, MRC Medical Research Council, RFCSA rectus femoris cross-sectional area