Value of Capnography During Nurse Administered Propofol Sedation (NAPS)

The Role of Capnography in Endoscopy Patients Undergoing Nurse Administered Propofol Sedation (NAPS): A Randomized Study

Propofol is widely used by anaesthesiologists for deep sedation and general anaesthesia. During recent years nurses trained in the use of low dose Propofol sedation (NAPS) during endoscopy have been introduced. The method has been implemented at the endoscopic unit at Gentofte hospital since 2008(1). Propofol has a respiratory depressive effect which may result in depressed oxygen saturation in the blood (hypoxia). Due to a short acting half life this is prevented in the majority of cases. However, in spite of this, hypoxia is experienced in 4,4% of patients receiving propofol during endoscopy at Gentofte Hospital (unpublished data). It is well known that hypoxia constitutes a late expression of reduced oxygen tension in peripheral tissues. Whether the addition of capnography to standard monitoring during NAPS may be of benefit is widely unknown. The aim of this study is to examine whether the additional use of capnography to standard monitoring during endoscopy may improve patient safety in patients undergoing low dose Propofol sedation by reducing the number, duration and level of hypoxic events. The trial is a randomized clinical prospective case-control study.

Inclusion Criteria:

• aged 18 or above
• compliant with the criteria of NAPS.

Exclusion Criteria:

• no signed written consent obtained
• American Society of Anaesthesiologists (ASA) physical status classification > 3
• sleep apnoea
• allergy against soy, eggs and peanuts
• body Mass Index (BMI) > 35 kg/m2
• mallampati Score ≥ 4
• acute gastrointestinal bleeding
• subileus
• ventricular retention
• severe COLD ((30% ≤ FEV1 <50%)
• failed data collection