BASICS of Colonoscopy
Basic Endoscope Components
Control Body
- Angulation mechanism: control knobs and angulation wires
- Optics OR Remote control function
- Valves: air/water and suction
Umbilical Cord
- Transmission
CCD cable, light bundle, air, water and suction
- External connections
air/water bottle, suction tubing, leak tester, diathermy safety cord, video processor cable
Conscious Sedation - usual IVI regimens
- Tranquillizer - Midazolam most commonly used
- Analgesia - Pethidine or Fentenyl
- NO “usual dose” 5mg midazolam and 50mg pethidine
What is Conscious Sedation?
- Patient responsive to verbal commands
- In particular, responds to request to take deep breaths, open eyes and show tongue
- Light tactile stimulation wakens patient
What is Deep Sedation?
- Patient un-responsive to verbal commands
- Light tactile stimuli fail to elicit response
- Inappropriate response to tactile/verbal stimulation
- Reflex response to stimulation is close to general anaesthesia
Safe Endoscopic Sedation
- Pre-procedure history - Co-morbidity, medication, alcohol, tobacco, previous experience
- Venous access and monitoring
- What dose to give?
- Effect of combination Rx
Essential Background Knowledge
- Haemoglobin oxygen dissociation curve
- Opiate and Benzodiazepine pharmacology
- Difference between “conscious sedation” and general anaesthetic
- CPR Training
Sedation Background
- Mono therapy safer than poly
- Oxygen dissociation curve (<90% dangerous)
- Synergism between opiates and Benzodiazepines
- Opiate uptake by receptors rapid (1 circulation time)
- Benzodiazepine uptake slow (2-3 mins)
Principles of Sedation
- Minimum dose
- Give in small increments
- Remember Midazolam takes 3 - 4 minutes to work
- Always give Opiate first, then Benzodiazepine
- Must have full cannula, not butterfly
- Antagonists must be immediately available
- Pulse oximetry and monitoring essential
- Routine use of oxygen supplementation
- Extra care in elderly, COPD, IHD etc
Monitoring
Conscious Sedation
- Always record the baseline pulse, (BP) and saturation level
- Test level of consciousness every minute initially
- WATCH PATIENT!!!!!!!!!
- Pulse oximetry
- Pulse monitoring
Safe Endoscopic Sedation - Safety at Hand
- Flumazenil - 250ug IVI
- Naloxone - 0.5 - 1ug/Kg
- Resuscitation equipment
General Principles
- Consent fully
- Avoid complications first: hot biopsy R side, beware large polyp, beware pain
- Recognise early
- Inform patient and relatives
- Consultant lead
Endoscopic skills
- Check endoscopic function before intubation
- Maintains luminal view inserts in luminal direction
- Awarence of patient coniousness and pain during the procedure and take appropriate action
- Use torque steering
- Intermittent suction
- Recognise and resolve loops
- Use position change and abd pressure
5 basic rules of colonoscopy
- Do not advance if no clear view of lumen
- Do not advance if any resistence
- Pull back if any doubt
- Little air as possible
- Attention to patient pain reaction.