NUR 318 Module 4 Quantitative Research Critique Example

Three Deep Breaths From a Gauze Pad: A Quantitative Critique of a Randomized Trial of Aromatherapy for Postoperative Nausea

Student Name

Edson College of Nursing and Health Innovation, Arizona State University

NUR 318: Nursing Research and Evidence Translation

Instructor Name

Month Day, Year

Three Deep Breaths From a Gauze Pad: A Quantitative Critique of a Randomized Trial of Aromatherapy for Postoperative Nausea

Introduction

Postoperative nausea is common in ambulatory surgery and can delay discharge. Nurses on my unit often hand patients an alcohol prep pad to sniff, but the evidence behind the practice is mixed. This paper critiques a randomized trial of aromatherapy for postoperative nausea (Hunt et al., 2013) using the critical appraisal questions in Polit and Beck (2022).

Research Problem and Purpose

The problem is clearly stated: antiemetic medications reduce but do not reliably prevent postoperative nausea, so an inexpensive, noninvasive treatment would be valuable. The purpose was to test aromatherapy as a treatment for patients who developed nausea after ambulatory surgery. The problem is significant for nursing because nurses deliver and can control this intervention.

Hypotheses

The primary hypothesis was that, compared with a placebo, nausea would be reduced by essential oil of ginger, an essential oil blend that included ginger and mint oils, or isopropyl alcohol. The secondary hypothesis was that effectiveness would depend on the agent. Both are directional and testable, though the secondary hypothesis does not predict which agent will work best.

Design

The study is a randomized trial with four arms and a saline placebo control, conducted at one ambulatory surgical center. Randomization of an intervention after nausea begins is a strength because it tests aromatherapy as a treatment, the way nurses use it, rather than as prevention. A limitation for internal validity is that blinding is difficult with scented agents: patients can smell the difference between ginger and saline, so expectations may influence self-reported nausea. The article's description of how allocation was concealed should be examined for this reason.

Sample

Of 1,151 patients screened, 303 who reported nausea were enrolled and 301 were analyzed. Eligibility included adults able to consent without coagulation problems or allergy to the agents. The sample is large enough to detect differences among four groups, and very few enrolled participants were lost. Because it came from one center, generalizability to other settings, surgeries and populations is limited. The proportion of screened patients who developed nausea, about one in four, also reflects that center's anesthesia practices.

Measurement

Nausea was measured on a verbal descriptive scale from 0 to 3, before treatment and 5 minutes after patients inhaled the agent three times. A simple scale suits a recovery area, but four points offer limited sensitivity, and a 5-minute outcome tells us about immediate relief, not whether nausea returned before discharge. Demographic and risk factors were collected before surgery, allowing the authors to examine whether groups were similar.

Procedures and Confounding

Prophylactic and rescue antiemetics were given as ordered or requested, which is realistic but introduces a potential confounder if antiemetic use differed among groups. Polit and Beck (2022) emphasize checking whether co-interventions were balanced. Readers should look for the authors' comparison of antiemetic use across arms.

Analysis and Results

The authors reported that the change in nausea was statistically significant for the essential oil blend compared with placebo, and they concluded that the primary hypothesis was supported and that effectiveness depended on the agent (Hunt et al., 2013). A key appraisal question is clinical significance: a one-point change on a 0 to 3 scale may matter a great deal to a patient, but the critique should consider how many patients moved from moderate to no nausea. Multiple comparisons among four arms also raise the risk of chance findings unless statistical adjustments were used.

Interpretation and Applicability

The authors called aromatherapy promising and recommended further research, a cautious conclusion that matches the single-center design and short follow-up. The findings are consistent with a Cochrane review that found low-certainty evidence that aromatherapy may reduce the severity of postoperative nausea (Hines et al., 2018).

For my unit, the study supports offering inhaled aromatherapy as an adjunct for mild to moderate nausea, alongside, not instead of, ordered antiemetics. It does not support relying on isopropyl alcohol alone as the main treatment. Before changing practice, our project should add a measurement of nausea at discharge and check for patients' fragrance allergies.

Conclusion

This randomized trial is a valuable, practical study with a large sample and a design that mirrors nursing practice. Limits in blinding, measurement and setting mean it should guide a carefully evaluated practice change rather than a firm standard.

References

Hines, S., Steels, E., Chang, A., & Gibbons, K. (2018). Aromatherapy for treatment of postoperative nausea and vomiting. Cochrane Database of Systematic Reviews, 2018(3), CD007598. https://doi.org/10.1002/14651858.CD007598.pub3

Hunt, R., Dienemann, J., Norton, H. J., Hartley, W., Hudgens, A., Stern, T., & Divine, G. (2013). Aromatherapy as treatment for postoperative nausea: A randomized trial. Anesthesia & Analgesia, 117(3), 597-604. https://doi.org/10.1213/ANE.0b013e31824a0b1c

Polit, D. F., & Beck, C. T. (2022). Essentials of nursing research: Appraising evidence for nursing practice (10th ed.). Wolters Kluwer.