Is Aromatherapy Effective for Apnea in Preterm Infants? A Systematic Review

Apnea can be associated with many complications such as bradycardia, cyanosis, hypotension, hypotonia, hydrocephalus, neurologic complications, and even death. Pharmacological treatment is associated with many side effects. We aimed to investigate the effect of aromatherapy on Apnea in premature newborns. An extensive search was done in databases of Medline, Embase, Scopus, Cochrane, and Web of Science until February 2019. Two independent researchers screened articles, in the next step, full texts of probably relevant articles were summarized and categorized based on the evaluated outcomes and overall effect size was presented. Three studies were included in the systematic review (including 110 preterm infants). Aromatherapy with breast milk odor not with vanilla odor, caused variability of premature infants’ heart rate blood oxygen saturation during and after venipuncture. Calming effects were observed when preterm newborns were exposed to either vanilla or breast milk odors during venipuncture; however, only breast milk odors had a calming effect on subjects after sampling. Breast milk odor was more effective regarding calming effects on premature infants. Infants in olfactory stimulation with anise or cinnamon were discharged from hospital 3.4 days earlier than the control group (p = 0.12).  A subgroup analysis of subjects with a body weight of 2,000 grams or more showed a shorter hospitalization period. When compared by gender, better effect was observed in boys than girls with shorter hospitalization in NICU. Conclusion Aromatherapy can be effective for apnea in preterm infants. Due to the small number of participants and low number of articles, the conclusion should be interpreted with caution.