title: Preemptive analgesia in rhegmatogenous retinal detachment surgery: is it effective?
abstract: OBJECTIVE
  To evaluate the efficacy of preemptive analgesia in surgical repair of retinal detachment (RD) using scleral buckle and cryopexy under general anesthesia.
  
  
  METHODS
  Thirty patients who were scheduled for rhegmatogenous RD surgical repair using scleral buckle and cryopexy and who were American Society of Anesthesiologists physical status I, II, or III were included in this study. The patients were randomly divided into two equal groups. The surgery was done under general anesthesia in both groups, but in Group 2, sub-Tenon anesthesia was given as preemptive analgesia after induction anesthesia and before start of surgery. Both groups were statistically comparable as regards patient age and weight and duration of anesthesia and surgery.
  
  
  RESULTS
  The incidences of intraoperative oculocardiac reflex and postoperative vomiting were significantly lower in Group 2 compared with Group 1 (P < 0.001 and 0.0113, respectively). The time of first postoperative analgesic dose was significantly shorter in Group 1 (46.67 +/- 18.84 minutes) compared with Group 2 (162.67 +/- 29.391 minutes) (P < 0.001). The total analgesic consumption per 24 hours was significantly higher in Group 1 compared with Group 2 (P < 0.001). The time of discharge from the hospital was significantly shorter in Group 2 (8.8 +/- 2.704 hours) compared with Group 1 (12.4 +/- 3.481 hours) (P = 0.0018).
  
  
  CONCLUSIONS
  The use of sub-Tenon block as preemptive analgesia after induction of general anesthesia and before the start of rhegmatogenous RD surgical repair was effective in reducing postoperative pain and analgesic requirements compared with an unblocked group. The use of sub-Tenon block was also effective in reducing intraoperative incidence of oculocardiac reflex and postoperative incidence of vomiting.
authors.affiliation: Anesthesia Department, Faculty of Medicine, Alexandria University, Egypt.
authors.forename: Abdul Kader M
authors.initials: AK
authors.lastname: Mahfouz
authors.forename: Khaled S
authors.initials: KS
authors.lastname: Nabawi
mesh_terms: D000293:Adolescent; D000328:Adult; D000698:Analgesia / Q000379:methods*; D000768:Anesthesia, General / Q000379:methods; D000772:Anesthesia, Local / Q000379:methods; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D000779:Anesthetics, Local / Q000008:administration & dosage; D002045:Bupivacaine / Q000008:administration & dosage; D003452:Cryosurgery; D006221:Halothane / Q000008:administration & dosage; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control; D008012:Lidocaine / Q000008:administration & dosage; D008875:Middle Aged; D010149:Postoperative Pain / Q000517:prevention & control; D010197:Pancuronium / Q000008:administration & dosage; D011343:Procaine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015742:Propofol / Q000008:administration & dosage; D012163:Retinal Detachment / Q000601:surgery*; D012591:Scleral Buckling
chemical_list: D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D000779:Anesthetics, Local; D011343:Procaine; D008012:Lidocaine; C005298:benoxinate; D010197:Pancuronium; D006221:Halothane; D002045:Bupivacaine; D015742:Propofol