Does the Use of Lidocaine in Dogs and Cats Reduce Post-Operative Tracheitis?
a Knowledge Summary by
Erik Fausak MSLIS, MA, CVT, LVT, RLAT1*
1Bel-Rea Institute of Animal Technology,1681 S Dayton St, Denver, CO 80247, USA
*Corresponding Author (firstname.lastname@example.org)
Vol 2, Issue 1 (2017)
Published: 03 Feb 2017
Reviewed by: Matyas Liptovszky (DVM, MSc, MRCVS)
Reviewed by: Bruce Smith (BVSc MS FANZCVS DACVS)
Next Review date: 20 Feb 2019
In dogs and cats, does the use of lidocaine lubricant on the endotracheal tube or placed on the glottis reduce tracheitis?
At Bel-Rea Institute of Animal Technology, shelter pets are routinely neutered and lidocaine lubricant is applied to the cuff and tip of endotracheal tubes to reduce post-operative sore throat or tracheitis. Incidence of sore throat after surgery has not been evaluated at our institution. Additionally, lidocaine is utilsed in feline intubation to reduce laryngospasm.
A systematic review in human medicine and 2 prospective veterinary studies were utilised.
Summary of the evidence
|Population:||10 cats average weight 3kg (8 males, 2 females), healthy.|
|Sample size:||40 (crossover)|
|Intervention details:||10 cats underwent induction and intubation four times: Group GTI0 was thiopental and intubation, Group GTIO+Lido was thiopental with 10% lidocaine sprayed on the glottis, Group Gprop was propofol and intubation, Group GProp+LIdo had propofol and 10% lidocaine sprayed on the glottis. All lidocaine spraying occurred on the glottis and the intubator waited 60-90 seconds before intubating. 15 days elapsed between the four procedures. All animals were previously sedated with acepromazine.|
|Study design:||Prospective, non-blinded, controlled, crossover study|
|Outcome Studied:||Respiratory, heart rate, pulse oximetry, number of intubation attempts, cough reflex, occurrence of laryngospasm, degree of relaxation of glottis, and need for additional induction agent.|
(relevant to PICO question):
|Lidocaine spray groups worked better with thiopental but no real difference was seen between the propofol groups with lidocaine or without.|
|Population:||32 healthy cats scheduled for elective surgery. No additional information.|
|Sample size:||32 cats|
|Intervention details:||Cats were separated into 4 groups:
Group 1 Lidocaine IV. Not specified.
Group 2 2% lidocaine applied to larynx, larynx was reviewed after induction. use of tuberculin syringe, with a 20g catheter that had 25g holes and the end sealed by heat.
Group 3 10% lidocaine aerosol (one "squirt") to larynx, larynx was reviewed after induction.
Group 4 no lidocaine. Not specified
Intubation was attempted 90 seconds after groups 1-3 were given lidocaine. One clinician intubated all animals.
|Study design:||Prospective, non-blinded, controlled|
|Outcome Studied:||The following were evaluated by the intubating clinician:
Amount of thiopental used for intubation
Amount of thiopental used for a smooth transfer to the inhalant
Laryngeal relaxation (only applied to groups 2 and 3)
# of attempts
# of coughs
Evidence of complications during extubation.
(relevant to PICO question):
|Less laryngospasm with topical lidocaine than IV or no treatment.
Fewer efforts were made with both topical lidocaine administrations.
Topical intubation allowed for larger Endotracheal tubes.
|Population:||Adult humans undergoing intubation.|
|Sample size:||1940 Adult Humans undergoing endotracheal intubation.|
|Intervention details:||Systematic review, study inclusion criteria:
Randomised control trials involving adult humans with varying degree of lidocaine use in endotracheal intubation (IV, spray, on the tube, in the cuff).
Databases searched were:
Cochrane Central Register of Controlled Trials (CENTRAL)
Medline, and Embase
Visual Aanalogue Scale (VAS) of sore throat.
Follow up duration was 12-30 hours post-operative
Two authors independently evaluated studies, but were not blinded to authors and institutions.
-endotracheal cuff was inflated with lidocaine
-lubrication of distal end of endotracheal tube with lidocaine
-spraying the glottis with lidocaine
-IV lidocaine administration
|Study design:||Systematic review with meta-analysis including 19 Randomised Control Trials.|
(relevant to PICO question):
|All approaches with lidocaine appear to have been beneficial to prevent sore throat.
No toxicities were reported in the use of lidocaine.
Didn't mention what portion of lidocaine lube administration included besides, "distal". Relevant information would include if “distal” endotracheal tube includes application on the cuff.
All studies had unclear risk of bias and received a lower GRADE (Trial evaluation criteria) score.
Appraisal, application and reflection
Veterinary appreciation of lidocaine's effect on post-operative sore throats is limited due to communication barriers between humans and other animals. Human research in some way provides greater advantage because patients could communicate the existence of sore throat after intubation, which occurs 30-70% of the time in Tanaka et al.'s (2015) study.
Veterinary study limitations for sore throat did not have a significant follow up time, to evaluate post-extubation sore throat. Future research should have better followup periods following lidocaine application. No veterinary study examines placement of lidocaine on the endotracheal tube.
Measurement of sore throat is another veterinary challenge because Visual Analogue Scales will not reliably work in determining severity of animal sore throats.
Despite the limitations in the quality of human research and surrogate outcomes measured in veterinary research, lidocaine by any route does seem to improve sore throat or laryngeal response with minimal toxicity concerns.
|Databases searched and dates covered:||Pubmed, VetMed Resource, and CAB Abstracts|
|Search terms:||Pubmed Sore Throat AND lidocaine AND intubation CABI and Vet Med Resource: lidocaine AND intubation|
|Dates searches performed:||12 April 2016|
|Exclusion / Inclusion Criteria|
|Exclusion:||Only systematic reviews and metanalysis were included from human medicine.|
|Inclusion:||Any relevant research with dogs, cats and systematic human reviews.|
Number of results
Excluded – human systematic reviews only
Excluded – relevance and species specific
Excluded – duplicates
Total relevant papers
Thomson Reuters Web of Science
Total relevant papers when duplicates removed
The authors declare no conflicts of interest.
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