Remifentanil and Fentanyl in Dental Surgery (REFEDS) (REFEDS)

Remifentanil vs Fentanyl During Day Case Dental Surgery in Persons With Special Needs: a Comparative Study of Their Effect on Stress Response and Postoperative Pain

This study was a prospective comparative study. The purpose of this study was to investigate the hypothesis whether remifentanil compared to fentanyl can induce less inflammatory and stress response to the day-case dental surgery in Persons with special needs (PSN). Secondary aims were to investigate comparatively their effect on patients intraoperative hemodynamic response and postoperative analgesia.

The study included 46 adult patients with cognitive impairment who underwent day-case dental surgery under general anesthesia with propofol aiming to keep a BIS-values range between 40-45. Nasal tracheal intubation was performed in all patients while neuromuscular blockade was achieved by rocuronium 0.6 mg/kg iv and repetitive doses of rocuronium of 10 mg iv, if needed. Patients were randomly allocated receive for intraoperative analgesia either fentanyl 50 μg iv bolus (group F, n=23) or continuous infusion of remifentanil 0.5-1 μg/kg/min (group R, n=23). Randomization was performed using using a computer-generated randomization schedule. Intraoperatively, patients in both groups received IV granisetron 3 mg, methylprednisolone 125 mg and clindamycin 600 mg, while atropine 0.02 mg/kg and neostigmine (0.05 mg/kg) was administered to to reverse neuromuscular blockade. Intraoperative monitoring included non-invasive measurement of arterial blood pressure, electrocardiogram, pulse oxymetry, capnography and Bispectral Sedation Index (BIS®). Postoperatively, patients remained under surveillance in the post-anesthesia care unit [PACU] for 3 h. Postoperative pain was assessed for the first 12 postoperative hours, at 30 min time-intervals for the first 3 hours, and every 3 hours thereafter by an independent observer, blinded to the study group, using the Wong-Baker faces pain rating scale (0-6). If pain scores were ≥3 a rescue dose of paracetamol 12.5 mg/kg iv was administered. Inflammation markers and stress hormones [cortisol, Tumor necrosis factor (TNF-a), substance-P, melatonin and β-endorphin] were measured in each patient before induction of anesthesia, after tracheal intubation and at the end of operation. Statistical Analysis was performed using Kolmogorov-Smirnov test, Student's unpaired t-test or Repeated Measures ANOVA with Holm's post-hoc analysis appropriately. A p value less than 0.05 was considered statistically significant.

Drug: Remifentanil (Ultiva). Intraoperative intravenous infusion of remifentanil 0.5-1 μg/kg/min for up to 1 h.

Drug: Fentanyl (FNT). Intraoperative administration of fentanyl given as one single bolus dose of 50 μg at the time of induction of anesthesia.

Intraoperative continuous infusion of remifenatanil. Remifentanil infusion was interrupted upon completion of surgical intervention.

Differences in intraoperative systolic arterial blood pressure values (mm Hg) between the two study groups

Measurements before the induction of anesthesia (baseline values) and at and 60 min (1 hour) after the induction of anesthesia

Measurements before the induction of anesthesia (baseline values) and at 60 min (1 hour) after the induction of anesthesia

Inclusion Criteria: Patients with cognitive impairment of category II according to the American Society of Anesthesiology (ASA) classification scheduled for elective dental surgery with short duration Exclusion Criteria: Patients of more than category II of American Society of Anesthesiology (ASA) classification Prolonged duration of surgery (>1 hour)