title: Safety of nurse-administered propofol sedation using PCA pump for outpatient colonoscopy in Chinese patients: a pilot study.
abstract: BACKGROUND
  To determine the safety and effectiveness of nurse-administered propofol sedation using patient-controlled analgesia (PCA) pump in outpatient colonoscopy in a Chinese population.
  
  
  METHODS
  From April to June 2005, 50 consecutive ASA class I or II patients aged 18-65 undergoing outpatient colonoscopy in an endoscopy centre of a regional hospital were prospectively recruited in this study. After a loading dose of 40-60 mg intravenous propofol, a mixture containing 14.3 mg propofol and 35 microg alfentanil were delivered via a patient-controlled syringe pump as bolus dose by an endoscopy nurse under the supervision of an endoscopist during the procedure. Lockout time was set to be zero. We aimed to achieve conscious sedation, with an Observers Scale for Sedation and Alertness (OSSA) score of 3. The primary outcome measure was complications from sedation, which included hypotension, bradycardia and desaturation. Other outcome measures included onset time, patients pain score, endoscopists and nurses satisfaction on the level of sedation, patients satisfaction regarding the procedure (measured by 10 cm visual analogue scale), and their willingness to repeat the procedure.
  
  
  RESULTS
  The mean lowest systolic blood pressure and mean arterial pressure (MAP) were 103.2 +/- 12.4 mmHg and 78.3 +/- 11.0 mmHg, respectively. The mean percentage drop in MAP was 15.7 +/- 11.9%. Six patients (12.2%) developed transient hypotension. Three patients (6.1%) had bradycardia. There was no episode of desaturation. The median onset time to reach OSSA score of 3 was 1 minute (range, 0.5-20.5). The OSSA score of 3 could be maintained throughout the procedure. The mean loading dose of propofol was 48.9 +/- 6.7 mg. The mean total dosages of propofol and alfentanil given were 124.2 +/- 38.1 mg and 184.3 +/- 93.7 mug, respectively. Endoscopists, endoscopy nurses and patients were highly satisfied with the sedation. The median pain score was 1 (range, 0-10; 0 = no pain, 10 = very painful), and the mean recovery time was 2.8 +/- 2.8 minutes. Most patients (93.9%) were willing to repeat the procedure.
  
  
  CONCLUSIONS
  Nurse-administered propofol sedation using PCA pump is safe and effective in sedation and pain control in outpatient colonoscopy in a healthy Chinese population.
authors.affiliation: Department of Surgery, North District Hospital, Sheung Shui, Hong Kong SAR.
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Poon
authors.forename: Tak-Lun
authors.initials: TL
authors.lastname: Leung
authors.forename: Chui-Wah
authors.initials: CW
authors.lastname: Wong
authors.forename: Yuk-Ling
authors.initials: YL
authors.lastname: Chan
authors.forename: Tin-Chun
authors.initials: TC
authors.lastname: Leung
authors.forename: Heng-Tat
authors.initials: HT
authors.lastname: Leong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000556:Ambulatory Surgical Procedures; D016058:Analgesia, Patient-Controlled / Q000451:nursing*; D002681:China; D003113:Colonoscopy; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D008875:Middle Aged; D010865:Pilot Projects; D015742:Propofol / Q000008:administration & dosage*; D011446:Prospective Studies
chemical_list: D006993:Hypnotics and Sedatives; D015742:Propofol