NR 505 Week 2 PICOT Question Write-Up Example Example

A PICOT Question on Gastric Residual Checks in Ventilated Adults, Argued Letter by Letter: Who Is Excluded and Why, a Comparison on the Same Axis, Calories With a Scale, and the Noninferiority Design the Sentence Commits To

Student Name

College of Nursing, Chamberlain University

NR 505: Advanced Research Methods: Evidence-Based Practice

Instructor Name

Month Day, Year

A PICOT Question on Gastric Residual Checks in Ventilated Adults, Argued Letter by Letter: Who Is Excluded and Why, a Comparison on the Same Axis, Calories With a Scale, and the Noninferiority Design the Sentence Commits To

The Concern Before the Acronym

The concern comes from my unit, the medical ICU where I work, with 20 beds. On a four-hour cycle we measure gastric residual volume in ventilated patients on tube feeding and hold the feeding for two hours if the volume is over 250 mL. In a two-week audit I did in August, 14 of 31 tube-fed ventilated patients had at least one feeding held for a high residual, and the median patient received about two-thirds of the calories the dietitian prescribed in the first week. The joint critical care and nutrition society guideline advises against using residual volume as a routine monitor for tube-fed ICU patients (McClave et al., 2016). My unit's routine and the guideline disagree, and I want to ask a question that could settle which one my unit should follow.

The question, in its final form, is: In adults on invasive mechanical ventilation in a medical ICU receiving gastric tube feeding started within 48 hours of intubation (P), does omitting routine gastric residual volume measurement, with feeding intolerance judged by vomiting or regurgitation (I), compared with residual measurement every 4 hours with feeds held for volumes over 250 mL (C), result in a higher percentage of prescribed calories delivered, without a higher rate of ventilator-associated pneumonia (O), over the first 7 days of tube feeding (T)? The rest of this paper explains each letter and what was rejected.

P: Bounded by What Would Change the Answer

The population is bounded only by features that could change the answer, not by every true fact about my patients. Mechanical ventilation is included because the outcome that worries staff, pneumonia from aspiration, is a risk specific to ventilated patients. Gastric feeding is included, and feeding beyond the stomach excluded, because a residual volume means something different when the tube tip is in the small intestine. Early feeding is included because the trial evidence was built on it.

I considered adding "excluding patients after abdominal surgery," which is true of my medical unit, and decided it was unnecessary because it does not apply to anyone my unit admits. I also considered excluding patients ventilated in the prone position, whose stomachs empty differently and whose feeding is often held for position changes. I kept them in, but I will check whether the evidence included them, because if it did not, the answer may not reach them.

I and C: A Comparison on the Same Axis

The intervention is stated with how it is delivered, because "no residual monitoring" alone does not describe what nurses will do. Under the intervention, nurses stop measuring residuals and judge intolerance only by vomiting or regurgitation. The comparison is our current practice, stated as precisely: measurement every four hours, with a hold at more than 250 mL.

The two arms sit on the same axis, the intensity of residual monitoring, which is what makes the comparison meaningful. I rejected a version that compared "no monitoring" with "usual care," because usual care on my unit varies between nurses, and a comparison with a moving target cannot be tested. I also rejected a version that raised the threshold to 500 mL instead of stopping monitoring altogether. That is a reasonable question, but it is a different one, on the same axis at a different point, and mixing the two would blur both.

O: An Outcome With a Scale Under It

The first outcome is the percentage of prescribed calories actually delivered, a continuous measure from 0% to 100% calculated from the pump record and the dietitian's prescription each day. I rejected "adequate nutrition" and "feeding tolerance" because neither has a scale; they describe a state of affairs, and two nurses could disagree about whether a patient had reached it.

The second outcome is ventilator-associated pneumonia, the harm the routine is supposed to prevent. It is included as a safety outcome, and it needs a definition someone could apply blind to group; the question will have to specify the definition before any data are collected. Reignier et al. (2013) had pneumonia judged by an adjudication committee kept unaware of allocation, which is the standard to meet.

Having two outcomes, one where I hope for improvement and one where I hope for no harm, is deliberate. A question with only the calorie outcome would miss the reason nurses fear the change. A question with only the pneumonia outcome would miss the reason to make it.

T: Seven Days

Seven days covers the period when most calorie deficits build up and most early pneumonia develops. A longer window would add patients who have left the unit, died or been extubated, and would weaken the connection between the feeding routine and the outcome. It also matches the time frame of my audit, so the answer will be comparable with what I already know about my unit.

What Kind of Answer Is Ordered

The question asks two different kinds of thing, and the wording has to show which is which. For calories, it asks whether the intervention is better, which is a superiority question. For pneumonia, it asks whether the intervention is not worse by more than an agreed amount, which is a noninferiority question. The phrase "without a higher rate" carries that second meaning, and it commits me to stating, before any data are gathered, how much worse would be too much. Reignier et al. (2013) set that margin at 10 percentage points. I will need to decide whether a margin that wide is acceptable to my unit, and I suspect many of my colleagues would want it narrower.

The Design the Sentence Has Bought

A causal question about a practice, with a noninferiority outcome, commits me to a randomized controlled trial as the design that could answer it directly: patients or units randomly assigned to each monitoring approach, with pneumonia judged by assessors blind to group. That is the design I will look for in the evidence, and it is not one my unit could run on its own.

For a unit-level project, the realistic design is weaker: a before-and-after comparison of calorie delivery and pneumonia rates on my unit, with the trial evidence as the basis for making the change. That design cannot establish cause, because anything else that changes between the two periods could explain the result. The question is worded for the trial; the project, if it happens, will be worded for what it can actually show.

References

McClave, S. A., Taylor, B. E., Martindale, R. G., Warren, M. M., Johnson, D. R., Braunschweig, C., McCarthy, M. S., Davanos, E., Rice, T. W., Cresci, G. A., Gervasio, J. M., Sacks, G. S., Roberts, P. R., & Compher, C. (2016). Guidelines for the provision and assessment of nutrition support therapy in the adult critically ill patient: Society of Critical Care Medicine (SCCM) and American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.). Journal of Parenteral and Enteral Nutrition, 40(2), 159-211. https://doi.org/10.1177/0148607115621863

Reignier, J., Mercier, E., Le Gouge, A., Boulain, T., Desachy, A., Bellec, F., Clavel, M., Frat, J.-P., Plantefeve, G., Quenot, J.-P., & Lascarrou, J.-B. (2013). Effect of not monitoring residual gastric volume on risk of ventilator-associated pneumonia in adults receiving mechanical ventilation and early enteral feeding: A randomized controlled trial. JAMA, 309(3), 249-256. https://doi.org/10.1001/jama.2012.196377