Diffusing essential oils is much different than pouring oils all over a patient (topical use should be used sparingly, and well diluted).
Here's some research:
"The focus of integrative therapies is on symptom control rather than cure. Nurses therapeutically use essential oils to enhance comfort, relieve pain, promote relaxation, alleviate sleep disturbances, reduce stress and anxiety, improve coping, and increase their patients' sense of well-being.3,4 Let the studies continue so that the scientific legitimacy of these interventions can be assessed further."
"Sleep deprivation in hospitalized patients is common and can have serious detrimental effects on recovery from illness. Lavender aromatherapy has improved sleep in a variety of clinical settings, but the effect has not been tested in the intermediate care unit...Conclusion Lavender aromatherapy may be an effective way to improve sleep in an intermediate care unit."
Effect of Lavender Aromatherapy on Vital Signs and Perceived Quality of Sleep in the Intermediate Care Unit: A Pilot Study
"There were 10,262 hospital admissions during the study time frame in which nurse-delivered aromatherapy was part of patient care. The majority of admissions receiving aromatherapy were females (81.71%) and white (87.32%). Over 75% of all aromatherapy sessions were administered via inhalation. Lavender had the highest absolute frequency (49.5%) of use regardless of mode of administration, followed by ginger (21.2%), sweet marjoram (12.3%), mandarin (9.4%), and combination oils (7.6%). Sweet marjoram resulted in the largest single oil average pain change at −3.31 units (95% CI: −4.28, −2.33), while lavender and sweet marjoram had equivalent average anxiety changes at −2.73 units, and ginger had the largest single oil average change in nausea at −2.02 units (95% CI: −2.55, −1.49)."
The effectiveness of nurse-delivered aromatherapy in an acute care setting - ScienceDirect
"Conclusion: Aromatherapy with lavender essential oil might reduce depression and stress among hemodialysis patients. Therefore, this method can be used as a complementary method with less complication to improve the quality of life of these patients."
The Effect of Aromatherapy with Lavender Essential Oil on Depression, Anxiety and Stress in Hemodialysis Patients: A Clinical Trial
"Given its positive effects on hemodynamic indices, aromatherapy can be used as an effective alternative therapy"
"In conclusion, the aromatherapy effectively reduced the anxiety levels and increased the sleep quality of PCI patients admitted to the ICU. Aromatherapy may be used as an independent nursing intervention for reducing the anxiety levels and improving the sleep quality of PCI patients."