Clinical trial NCT01444703: Comparison of Licorice Versus Sugar-water Gargle for Prevention of Postoperative Sore Throat and Postextubation Coughing
Official title: Randomized, Double-blind Comparison of Licorice Versus Sugar-water Gargle for Prevention of Postoperative Sore Throat and Postextubation Coughing
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Sore Throat
Keywords: Thoracic surgery
double-lumen endotracheal tube
intubation
extubation
sore throat
prevention of post-extubation sore throat
Lead sponsor: The Cleveland Clinic
Sponsor class: OTHER
First posted: 2011-10-03
Enrollment: 236
Sex: ALL
Minimum age (years): 18
Maximum age (years): 90
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: SUPPORTIVE_CARE

Brief summary: The investigators propose to test the hypothesis that pre-operative gargling with licorice reduces the incidence of sore throat in rest after intubation with double-lumen endotracheal tubes compared to placebo after surgery through the first four post-extubation hours.

Detailed description: Patients will be premedicated with up to 7.5 mg p.o. midazolam, per routine. They will be told that the study involves two different solutions for prevention of post-extubation sore throat.

Patients will be randomly assigned to gargle 5 minutes before induction of general anesthesia with: 1) licorice (0.5 g); or, 2) sugar (5 g). Randomization will be based on a computer-generated table of random numbers. Licorice or sugar (placebo) will be diluted in 30 ml water and filled in a small bottle by an independent apothecary of our university. All bottles will look similar and will not be opened until just before use. Investigator and patient will be blinded to the preparation used for gargle. Patients will be asked to gargle for two minutes, but not to swallow the solution.

General anesthesia will be induced with fentanyl ≈3 µg/kg, propofol ≈1.5 mg/kg, and rocuronium ≈0.6 mg/kg. Complete muscle relaxation will be confirmed by absence of palpable twitches in response to supra-maximal train-of-four stimulation of the ulnar nerve at the wrist. The trachea will then be intubated as gentle as possible. Intubation will be attempted with a Macintosh laryngoscope, but the anesthesiologists may subsequently use any other intubation equipment as necessary. Initial tube size will be 37 cm left in women and 39 cm left for men; however, other sizes can be used if clinically necessary. Endotracheal tube cuffs will be inflated with air to 20-25 mmHg as necessary to maintain an adequate seal.

General anesthesia will be primarily be maintained with sevoflurane. Patients lungs will be ventilated with O2 in air, usually with an inspired oxygen fraction (FiO2) of ≈40%. However, additional oxygen will be provided as clinically necessary, especially during one-lung ventilation. End-tidal CO2 will be maintained between 32 and 35 mmHg as clinically practical. Deep of anesthesia will be monitored by using bispectral index BIS, kept between 40 and 50. Small amounts of opioid will be permitted during surgery and in preparation for extubation. At the end of surgery, an intercostal plexus block -using up to 20 ml Ropivacaine 0.1% - will be performed by the surgeons. 1000 mg paracetamol will be given intravenously ten minutes before end of surgery. Post operative pain will be treated with fractional piritramid (Dipidolor) 3 mg IV as required.

Eligibility criteria: Inclusion Criteria:

* Thoracic surgery with anticipated use of a double-lumen endotracheal tube;
* Anticipated extubation in the operating room;
* ASA Physical Status 1-3;
* Age 18- 90

Exclusion Criteria:

* Tracheal pathology, including tracheostomy;
* Surgery within the previous four weeks;
* Upper-respiratory tract infection;
* BMI higher exceeding 40 kg/m2;
* Known or suspected allergy to licorice;
* Use of non-steroidal anti-inflammatory drug medication within 24 hours;
* Chronic opioid use;
* Preoperative pain ≥ 2 on an 11-point Likert scale (0 = no pain; 10 = worst pain);
* Known or suspected difficult airway.

Primary outcomes:
measure: sore throat in rest after intubation
timeFrame: up to 4 hours post-extubation
Secondary outcomes:
measure: post-extubation coughing
timeFrame: up to four hours post-extubation
measure: amount of coughing
timeFrame: 24 hours post operative
measure: sore throat in rest
timeFrame: first 24 hours after surgrey
measure: incidence of sore throat during swallowing
timeFrame: first 24 hours after surgery
Other outcomes:
Locations:
city: Vienna
country: Austria
facility: Universitätsklinik für Anästhesie, Intensivmedizin und Schmerztherapie an der medizinischen Universität Wien
Study officials:
affiliation: Outcomes Research Consortium, Cleveland Clinic
name: Daniel Sessler, MD
role: STUDY_CHAIR
References:
citation: Ruetzler K, Fleck M, Nabecker S, Pinter K, Landskron G, Lassnigg A, You J, Sessler DI. A randomized, double-blind comparison of licorice versus sugar-water gargle for prevention of postoperative sore throat and postextubation coughing. Anesth Analg. 2013 Sep;117(3):614-621. doi: 10.1213/ANE.0b013e318299a650. Epub 2013 Aug 6.