MN504 Unit 4 Sample Paper

Daily Chlorhexidine Bathing and Central Line Bloodstream Infections in a 24-Bed Adult Medical Intensive Care Unit: A Critical Appraisal of the Evidence Behind One PICOT Question

[Author Name]

School of Nursing, Purdue University Global

MN504 Evidence-Based Practice

Unit 4 Assignment

[Faculty Name]

August 11, 2026

Original model document. The unit, its infection rate and its staff are composites; no real hospital, patient or clinician is described.

What this page is doingThe title names the intervention, the outcome, the setting and the document type, so a reader knows what was appraised before reading a word of the paper. The course and unit lines carry the classroom's own vocabulary instead of a fabricated deliverable name, which keeps the page honest where the unit's exact requirement is not published. The closing line marks the unit and its rate as composites. Graders reward a title that could belong to no other paper; a generic label such as Evidence-Based Practice Paper gives that credit away for nothing.

The Practice Problem and the PICOT Question

The setting is a composite 24-bed adult medical intensive care unit inside a 400-bed community teaching hospital. Over the 12 months ending June 30, the unit recorded 14 central line-associated bloodstream infections across 6,730 central line days, a rate of 2.1 infections per 1,000 central line days. A rate needs its comparison: pooled means reported through the National Healthcare Safety Network for adult medical intensive care units sit below 1.0 per 1,000 central line days (Centers for Disease Control and Prevention, 2024). The unit is running near twice that mean, and has done so across four consecutive quarters rather than in one bad month. Insertion bundle audits have held above 95 percent over the same period, which moves the question away from insertion and toward maintenance and skin flora.

The Agency for Healthcare Research and Quality (2022) places attributable mortality for these infections between 12 and 25 percent and attributable cost in the tens of thousands of dollars per episode, which makes 14 infections a safety and budget problem at once. Skin colonization is the mechanism most open to nursing action once insertion practice is sound, since organisms migrate along the external catheter surface from the patient's own skin. That reasoning produced the question this paper appraises: In adults with a central venous catheter admitted to a 24-bed adult medical intensive care unit (P), does daily bathing with 2 percent chlorhexidine gluconate impregnated cloths (I), compared with daily bathing using soap and water (C), reduce the rate of central line-associated bloodstream infection per 1,000 central line days (O) over a 12-month period (T)?

The question is deliberately narrow. It does not ask whether chlorhexidine bathing lowers mortality, prevents surgical site infection, or should be paired with nasal decolonization, because each of those pulls in a separate body of evidence. It also fixes a comparator the unit really uses, basin bathing with soap and water, rather than an idealized control no one practices. Naming the outcome in the surveillance form the unit already reports means the answer can be tested against data infection prevention collects anyway, with no new measurement burden. A question that cannot be measured with existing data usually dies during implementation.

What this page is doingThe rate arrives with its denominator and its window, and the national comparison arrives with it, because 14 infections means nothing until a reader knows it happened across 6,730 central line days and how that compares. The insertion bundle audit result is doing quiet work here: it is the sentence that justifies asking about maintenance rather than insertion. The PICOT question then falls out of the problem instead of being announced at the top, and its comparator is the practice the unit really uses. A rubric row asking for a focused question is asking for that chain.

Search Strategy and What the Search Returned

Three databases were searched for different reasons: CINAHL Complete for nursing intervention studies, MEDLINE through PubMed for critical care and infectious disease trials, and the Cochrane Library for synthesized evidence. The string combined three concept blocks: (chlorhexidine OR 'chlorhexidine gluconate' OR 'CHG bathing') AND ('central line-associated bloodstream infection' OR CLABSI OR 'catheter-related bloodstream infection') AND ('intensive care' OR ICU OR 'critically ill'). Limits were English language, adult subjects, peer reviewed, and publication from 2013 through 2025, a window that opens with the first large multicenter trial rather than at an arbitrary round number. The first pass returned 412 records, 63 survived title and abstract screening, and 21 were read in full.

Six sources were retained, and each is labeled by level rather than left in an undifferentiated pile of citations. Using the hierarchy in Melnyk and Fineout-Overholt (2023), the review by Lewis and colleagues (2019) enters as Level I, a systematic review of randomized trials. Climo and colleagues (2013) and Noto and colleagues (2015) enter as Level II, both multi-unit randomized crossover trials. The Agency for Healthcare Research and Quality (2022) toolkit and the Centers for Disease Control and Prevention (2024) surveillance manual enter as Level VII, agency and expert guidance, which is where they belong: they define the outcome and describe implementation, but they cannot establish effect. Fifteen studies were excluded for pediatric populations, non-bathing interventions, or outcomes limited to colonization.

The two randomized trials disagree, and this appraisal is easier to follow if that is said before either is described. Climo and colleagues (2013) randomized 7,727 patients across nine intensive care and bone marrow transplant units in six hospitals to daily bathing with chlorhexidine impregnated cloths or with non-antimicrobial cloths, and reported roughly a 28 percent reduction in the rate of hospital-acquired bloodstream infection. Noto and colleagues (2015) randomized approximately 9,300 patients in five adult intensive care units at a single academic center and found no difference in a composite of health care-associated infections. The review that later pooled this literature rated certainty low for most outcomes and found no clear effect on mortality (Lewis et al., 2019).

What this page is doingDatabases, the Boolean string, the limits, the date window with a reason for its start, and the yield at each screening step all appear, which is what separates a graduate appraisal from an undergraduate summary. Labeling each retained source by level does the same work in one word per source: it tells the reader which citations can establish an effect and which can only define the outcome or describe implementation. Stating the disagreement between the two trials before describing either one prevents a tidy conclusion the evidence will not support.

Appraising the Retained Evidence: Design, Disagreement and Certainty

Both trials share a design strength and a design weakness. Cluster randomization with crossover suits a unit-level intervention, since bathing practice cannot be blinded or assigned bed by bed without contamination, and crossover lets each unit serve as its own control. What neither trial can do is blind the people who collect the outcome. That matters more than usual here, because a central line-associated bloodstream infection is a surveillance construct applied by a trained reviewer against written criteria (Centers for Disease Control and Prevention, 2024), not a result a laboratory returns. Any shift in how aggressively cultures are drawn, or in how a reviewer applies criteria once a unit knows its bathing changed, moves the reported rate without moving the underlying biology.

The disagreement between the two trials is informative rather than disqualifying. The single-center trial ran in units whose baseline infection rates were already low, and it measured a composite outcome that folded catheter infections in with urinary infections, ventilator-associated events and Clostridioides difficile, so a real effect on one component could be diluted by no effect on the others. Baseline rate is the variable that carries this appraisal to a decision. A relative reduction of a quarter is worth almost nothing where the rate already sits below 1.0 per 1,000 central line days, and worth 3 to 4 infections a year on a unit at 2.1 across 6,730 line days. The composite unit here is the second kind of unit.

The honest reading is that this evidence supports a trial of practice change and does not support a claim of certainty. Certainty was rated low in the pooled review, a mortality benefit was not demonstrated, and the literature carries two signals worth monitoring: reduced chlorhexidine susceptibility in some staphylococcal isolates after sustained exposure, and skin reactions that are usually mild but occasionally end therapy for a patient. Generalizability is imperfect as well, since most participants came from academic centers with dedicated infection prevention staffing rather than from a 400-bed community hospital. None of that argues against acting. It argues for acting with a measurement plan and a date to look at the result.

What this page is doingThis is where appraisal earns its name. The paper judges the designs, identifies the specific threat that matters here, an unblinded surveillance outcome rather than a laboratory result, and then explains the conflicting trial instead of waving it off. The move that turns appraisal into a decision is the baseline-rate argument: the same relative effect is worth different amounts on different units. Naming reduced susceptibility, skin reactions and imperfect generalizability costs the writer nothing and buys credibility, since a reader who knows this literature would notice their absence.

What Would Change in Practice, and What Would Not

The recommendation is a 12-month unit-level change with a defined end point. Every adult in the unit with a central venous catheter would be bathed once daily with 2 percent chlorhexidine gluconate impregnated cloths, one cloth per body region, no rinse, with the insertion site and surrounding skin cleaned last so the cloth never travels toward the line. Soap and water would remain in use for the face and for patients with documented sensitivity. Priced at the unit's contracted rate near $5 per patient-day across roughly 7,900 patient-days a year, the supply line adds close to $40,000 annually, set against 14 infections whose attributable costs run in the tens of thousands each.

Measurement is written before the change starts rather than after it. The process measure is documented completion of chlorhexidine bathing, audited on 20 randomly selected patient-days each month, with a target of 90 percent by the end of the second quarter. The outcome measure is the unit's existing infection rate per 1,000 central line days, plotted by quarter against the four quarters preceding the change. Balancing measures are documented skin reactions and any rise in staphylococcal isolates the laboratory reports as less susceptible to chlorhexidine. If bathing compliance stays below 70 percent at six months, the failure is implementation rather than intervention, and the question has not been answered.

Several things would not change, and saying so protects the recommendation. The insertion bundle stays as it is, because compliance above 95 percent is not the problem this evidence addresses. Nasal decolonization is not added, since no retained source tested it. The practice does not extend to patients without central lines or to units outside adult critical care, both outside the population the question named. Nothing here supports telling a family that bathing lowers the chance of dying. Approval from infection prevention, pharmacy and the unit practice council would precede any change, and that council would receive the 12-month result whether it favors the practice or not.

What this page is doingThe recommendation is specific enough to audit: who is bathed, with what, in what order, at what cost, and until when. Process, outcome and balancing measures are named before the change begins, which is the difference between practice change and enthusiasm. The compliance threshold protects the conclusion, because a failed rollout and a failed intervention look identical in outcome data. The closing list of what would not change keeps the paper inside the population and the outcome its own question named, which is where a scope row is won.

References

Agency for Healthcare Research and Quality. (2022). Toolkit for reducing central line-associated blood stream infections. U.S. Department of Health and Human Services. https://www.ahrq.gov/hai/clabsi-tools/

Centers for Disease Control and Prevention. (2024). National Healthcare Safety Network (NHSN) patient safety component manual. U.S. Department of Health and Human Services. https://www.cdc.gov/nhsn/

Climo, M. W., Yokoe, D. S., Warren, D. K., Perl, T. M., Bolon, M., Herwaldt, L. A., Weinstein, R. A., Sepkowitz, K. A., Jernigan, J. A., Sanogo, K., & Wong, E. S. (2013). Effect of daily chlorhexidine bathing on hospital-acquired infection. New England Journal of Medicine, 368(6), 533-542.

Lewis, S. R., Schofield-Robinson, O. J., Rhodes, S., & Smith, A. F. (2019). Chlorhexidine bathing of the critically ill for the prevention of hospital-acquired infection. Cochrane Database of Systematic Reviews, 2019(8). Cochrane Library. https://www.cochranelibrary.com

Melnyk, B. M., & Fineout-Overholt, E. (2023). Evidence-based practice in nursing and healthcare: A guide to best practice (5th ed.). Wolters Kluwer.

Noto, M. J., Domenico, H. J., Byrne, D. W., Talbot, T., Rice, T. W., Bernard, G. R., & Wheeler, A. P. (2015). Chlorhexidine bathing and health care-associated infections: A randomized clinical trial. JAMA, 313(4), 369-378.

How this MN 504 Unit 4 example is structured

In many sections this unit asks for a critical appraisal built on a single PICOT question; your classroom's instructions and the rubric posted with the assignment decide the exact form, so read them before borrowing this shape. This MN504 Unit 4 example is ordered the way an appraisal earns its conclusion. The first sheet fixes the problem in numbers, so the question has something to be about. The second shows the search itself, with databases, terms, limits and yield, because a search a reader cannot repeat is only an opinion with citations attached. The third judges what came back, including the trial that disagrees, and names the level of evidence for each retained source. The last sheet says what would change at the bedside and what would not. The unit and its rate are composites.

MN504 Unit 4 questions, answered

What does MN504 Unit 4 usually ask for?

In many sections this unit asks for a critical appraisal of the evidence behind one PICOT question, with a stated search strategy and a judgment about the quality of what the search returned. The exact form belongs to your classroom, so read the assignment instructions and the rubric posted in the unit before you set your sections, since required elements vary by section and term.

What makes a critical appraisal different from a summary of the articles?

A summary reports what each study said. An appraisal says whether each study can support the claim being made, then explains the disagreements between them. That means naming the design, the sample, the level of evidence and the specific threat to validity, and closing with a practice decision the evidence can carry. If your paper never says a study is weak, it is still a summary.

Can I submit this MN504 Unit 4 example as my own paper?

No. This is an original model document written by our desk to show what a finished appraisal looks like. It was never submitted, never graded, and holds no official status. Use it to see how a question, a search and a judgment hold together, then build your own from your own question and sources. Copying any part of it is plagiarism.

Write yours, or have the desk draft it

This paper is an original model document written by our desk, not a submitted student paper and not an official Purdue University Global document. Read it for the moves, then write your own to the instructions in your classroom. If you want one built to your exact prompt and rubric, the first custom sample is free and arrives in 24 to 48 hours.

MN504 Unit 4: sample paper, in real form