Balanced conscious sedation with intravenous induction and inhalational maintenance for patients requiring endoscopic and/or surgical procedures.
OBJECTIVE
The use of inhalation sedation with sub-anaesthetic concentrations of sevoflurane and nitrous oxide mixture is expected to reduce amounts of intravenous sedative drugs needed to produce a balanced sedation with the benefits of having reduced side-effects.


METHODS
Eighty-two patients requiring endoscopic and/or surgical procedures under conscious sedation and local anaesthesia were recruited for this pilot study. Conscious sedation was induced with a titrated dose of midazolam and propofol given intravenously until the clinical end-point of conscious sedation was achieved. Subsequently, during the procedure, the patient was asked to breathe sevoflurane 0.1-0.3% and a fixed ratio of 40% nitrous oxide in oxygen given through a face mask.


RESULTS
In 78 patients (95.1%), the treatment was completed successfully. Patients were discharged back to the wards within 4-16 min (10.1) without significant side-effects. Treatment was satisfactorily accepted by 38 patients (48.7%) and considered excellent by 40 patients (51.3%).


CONCLUSIONS
The use of titrated doses of intravenous sedative drugs for induction of conscious sedation followed by the use of low concentrations (0.1-0.3%) of sevoflurane combined with 40% nitrous oxide for maintenance of conscious sedation in patients requiring endoscopic and/or surgical procedures under local anaesthesia, has the potential advantages of reducing amounts of intravenous sedative drugs, less likelihood of problems from drug side-effects and fast recovery and discharge time. Further investigations to establish the technique are currently in progress.
Lahoud
G Y
GY
University of Leeds, Academic Unit of Anaesthesia, St. James's University Hospital, Leeds, UK. delahoud@aol.com
Hopkins
P M
PM
D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000772:Anesthesia, Local / Q000379:methods; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D016292:Procedural Sedation / Q000009:adverse effects / Q000379:methods*; D004724:Endoscopy / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous / Q000379:methods; D007902:Length of Stay; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage / Q000627:therapeutic use; D008874:Midazolam / Q000008:administration & dosage / Q000627:therapeutic use; D008875:Middle Aged; D009609:Nitrous Oxide / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D017060:Patient Satisfaction; D010865:Pilot Projects; D015742:Propofol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D000077149:Sevoflurane; D013514:Surgical Procedures, Operative / Q000379:methods*; D016896:Treatment Outcome
D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D000077149:Sevoflurane; D009609:Nitrous Oxide; D008874:Midazolam; D015742:Propofol