Methods
This study was a prospective double-blinded parallel randomized clinical trial conducted at Torabinejad Dental Hospital in School of Dentistry, Isfahan University of Medical Sciences, Iran. The protocol to this study was submitted under the code of IRCT20190626044013N2 in the Iranian Registry of Clinical Trials. This study was registered at Ethics Committee of Isfahan University of Medical Sciences, Isfahan, Iran under registration code: IR.MUI.RESEARCH.REC.1399.763 at 3 March 2021.
This trial was conducted in complete accordance with the Declaration of Helsinki. [8] Power analysis showed that a sample size of 25 in each group was needed for a significance level set at 0.05 and a power of 80%. The participants (aged 10-50 years) were intellectually disabled without systemic problems or physical disability, who needed to receive dental services under general anesthesia. The patients were considered to have intellectual disability if they had problems in both intellectual and adaptive functioning in conceptual, social and practical domains according to American Psychiatric Association. [9] The exclusion criteria were patients who used anti-depressants, anti-convulsive, anti-psychotic, anti-hypertensive or tranquilizer drugs. Patients suffering from hepatic disorders, allergic to soybeans or eggs and those with a body mass index (BMI) equal to or more than 40 were also excluded. Using the simple sampling method, 50 patients referring to the dental hospital center were included in the study. An informed consent was obtained from the patient’s guardian before enrolment in the study.
Patients were randomly divided into intervention and control groups using a computer‐generated sequence with an allocation ratio of 1:1. The patients were blind to their category, and their allocation was concealed in sequentially numbered, opaque sealed envelopes prior to the beginning of procedure. Patient enrolment and intervention assignment was carried out by a person unaware of the content of envelopes. In both groups, the drug regimen used to induce anesthesia was 5 mg/kg of sodium thiopental (VUAB Pharm Inc, Roztoky, Czech), 0.8 mg/kg of atracurium (Caspian Tamin, Rasht, Iran), and 1-2 mcg/kg of fentanyl (Aburaihan Pharmaceutical, Tehran, Iran), and maintenance was achieved with propofol (Dangkook Pharm, Choong Cheong Book-Do, Korea) at a rate of 100 mcg/kg/min. After the induction of anesthesia, the intervention group received additional doses of dexmedetomidine (Exir Pharmaceutical Co, Borujerd, Iran) by infusion with a rate of 2 mcg/kg/h as an anesthetic adjuvant until the end of anesthesia. For the control group, equal amounts of 0.9% saline were administered as placebo.
Patients’ demographic information was recorded before the procedure. During the anesthesia, the patient’s systolic and diastolic blood pressures for every 15 minutes, the duration of anesthesia, and the type and number of dental treatments performed were recorded. If a patient had pain or restlessness in recovery, the relevant symptoms were recorded and analgesia was prescribed as per need. The Richmond Agitation Sedation Scale (RASS) was used to assess patients’ agitation levels in the recovery. [10] The recovery time for each patient was recorded before they got discharged. Patients were discharged only after they scored at least 9 in the Post Anesthesia Discharge Scoring System. Assessments were done by a person who was blind to the intervention, and the obtained data were analyzed by independent t-test, repeated measures analysis of variance (ANOVA), LSD post-hoc and Mann-Whitney tests using SPSS (Clarivate Analytics) version 23 software.