Intracuff lidocaine

I highly doubt this will constitute examinable material, however it is interesting, and after all - that's why we're here.

The take home messages

• You can put lidocaine in the ET tube cuff
• It will probably help a little to prevent coughing on emergence and sore throat after the operation
• Very few people do it
• Pointless if the procedure is less than 30 mins

How it works

Not especially complicated - you shove a load of local anaesthetic into the cuff, and it diffuses through the membrane of the cuff itself and into the tracheal mucosa, providing gentle topical anaesthesia to the areas in physical contact with the tube.

Invented in 1943 by Swedish chemist Nils Löfgren, lidocaine was the first amide local anaesthetic agent to hit the market, massively outperforming the main contender at the time procaine in terms of:

• Speed of onset
• Duration of action
• Risk of allergic reaction
• Stability in solution

And once PVC cuffs became more common on endotracheal tubes from the 1990s onwards, this new off-label route of administration started to come into fashion.

Most modern endotracheal tubes have some form of polyvinyl chloride cuff, which fat soluble drugs can diffuse through passively without too much encouragement.

If you add bicarbonate to your lidocaine, you play with the pKa and keep more of the lidocaine molecules in their unionised state, allowing them to diffuse across the cuff, much like any other lipid membrane in the body.

The recipe

• 4% lidocaine with 8.4% bicarbonate appears to be the standard approach
• Mix 2 mL 8.4% NaHCO₃ with 8 mL 4% lidocaine to make 10 mL of alkalinised solution
• But you can also use 2%, 10%, non-alkalinised, anything by the sounds of it
• Cuff needs to be entirely filled with liquid, air will make absorption slow and patchy

Evidence

The results of this meta-analysis of 11 RCTs involving 843 patients showed that the administration of alkalinized or non-alkalinized lidocaine to endotracheal tube cuffs significantly reduced coughing on tube and other intubation-related complications (i.e., hoarseness, agitation/restlessness and/or dysphonia) during the extubation process. In addition, by comparison with controls, intracuff administration of alkalinized lidocaine tended to be more effective than non-alkalinized lidocaine. Importantly, the outcome was similar when studies with high risk patients (i.e., children, smokers and those with hyperactive airways)^21,23,24 were excluded from the analysis. However, according to GRADE recommendations the studies were classed as ‘low level of evidence quality’ and results from a funnel plot indicated potential publication bias.

Efficacy of intracuff lidocaine in reducing coughing on tube: a systematic review and meta-analysis - PMC

To investigate the efficacy of intracuff lidocaine in reducing coughing and other endotracheal tube side effects and so ensure a smooth extubation process. PubMed, EMBASE, and Cochrane Library databases were systematically searched for all…

NCBI home page

Lidocaine 10% in the endotracheal tube cuff: blood concentrations, haemodynamic and clinical effects - PubMed

The purpose of this study was to evaluate the effects (common haemodynamic variables, peak cuff pressures, the incidence of reaction (‘bucking’) during extubation and the incidence of sore throat after operation) of lidocaine 10% instilled into the endotracheal tube cuff in intubated patients. Plasm …

PubMedF Altintaş

Lidocaine in the endotracheal tube cuff reduces postoperative sore throat - PubMed

Using lidocaine to inflate the ETT cuff decreases the severity of postoperative sore throat at one hour, and both the incidence and severity at 24 hours.

PubMedR M Navarro

Effect of cuff inflation with lidocaine, saline, and air on tracheal tube cuff pressure during laparoscopic resection of colorectal neoplasms: a randomized clinical trial - BMC Anesthesiology

Background Tracheal tube cuff pressure will increase after pneumoperitoneum when the cuff is inflated with air, high pressure can cause tracheal mucosal damage. This prospective trial aimed to assess if inflating with normal saline or lidocaine can prevent increase of tracheal tube cuff pressure and tracheal mucosal damage in laparoscopic surgeries with general anesthesia. Whether changes of tracheal tube cuff transverse diameter (CD) can predict changes of tracheal tube cuff pressure. Methods Ninety patients scheduled for laparoscopic resection of colorectal neoplasms under general anesthesia were randomly assigned to groups air (A), saline (S) or lidocaine (L). Endotracheal tube cuff was inflated with room-temperature air in group A (n = 30), normal saline in group S (n = 30), 2% lidocaine hydrochloride injection in group L (n = 30). After intubation, tracheal tube cuff pressure was monitored by a calibrated pressure transducers, cuff pressure was adjusted to 25 cmH2O (T0.5). Tracheal tube cuff pressure at 15 min after pneumoperitoneum (T1) and 15 min after exsufflation (T2) were accessed. CD were measured by ultrasound at T0.5 and T1, the ability of ΔCD (T1-0.5) to predict cuff pressure was accessed. Tracheal mucous injury at the end of surgery were also recorded. Results Tracheal tube cuff pressure had no significant difference among the three groups at T1 and T2. ΔCD had prediction value (AUC: 0.92 [95% CI: 0.81–1.02]; sensitivity: 0.99; specificity: 0.82) for cuff pressure. Tracheal mucous injury at the end of surgery were 0 (0, 1.0) in group A, 0 (0, 1.0) in group S, 0 (0, 0) in group L (p = 0.02, group L was lower than group A and S, p = 0.03 and p = 0.04). Conclusions Compared to inflation with air, normal saline and 2% lidocaine cannot ameliorate the increase of tracheal tube cuff pressure during the pneumoperitoneum period under general anesthesia, but lidocaine can decrease postoperative tracheal mucosa injury. ΔCD measured by ultrasound is a predictor for changes of tracheal tube cuff pressure. Trial registration Chinese Clinical Trial Registry, identifier: ChiCTR2100054089, Date: 08/12/2021.

BioMed CentralXuan Wang

Intracuff lidocaine 2% for prevention of postoperative... : Al-Azhar Assiut Medical Journal

uff membrane to anesthetize the mucosa and attenuate stimulation during tracheal extubation. Aim To evaluate the efficacy of intracuff lidocaine 2% for the prevention of postoperative cough and sore throat. Patients and methods This prospective, randomized, controlled, double-blind study included 80 healthy patients scheduled for elective surgery of less than 2 h under general anesthesia with orotracheal intubation. These 80 patients were randomized through a computer-generated and sealed opaque envelope method into four equal groups, with 20 patients each. After induction of general anesthesia and tracheal intubation, the tracheal tube cuff was filled with 2 ml of 2% lidocaine solution (40 mg) or 0.9% saline. Twenty minutes before extubation, the participants received 1.5 mg/kg intravenous lignocaine or saline. In this way, four groups were formed: lidocaine cuff–lidocaine group (lidocaine in cuff and lidocaine intravenous), lidocaine cuff–saline group (lidocaine in the cuff and saline intravenous); saline cuff–lidocaine group (saline in cuff and lidocaine intravenous), and saline cuff–saline group (saline in cuff and saline intravenous). The primary outcome was the incidence of coughing at extubation. The secondary outcomes were sore throat scores and hemodynamic change. The incidence and severity of sore throat was recorded at 15, 60 min, and 24 h after extubation. Hemodynamic change was assessed at before induction (baseline), 5-min interval after induction, at intubation, 10 min after intubation, 10 min before extubation, at extubation, and 10 min after extubation. Result There was a statistically significant reduction of postoperative cough and sore throat in lidocaine cuff groups in comparison to saline cuff groups. Intravenous lidocaine was not effective to reduce either cough or sore throat severity. However, there was no significant difference among all groups regarding hemodynamic change. Conclusion Intracuff lidocaine 2% reduces incidence of cough and the severity of postoperative sore throat in surgery of less than 120 min. Intravenous lidocaine was not effective to reduce either cough or sore throat severity. There was no significant difference among all groups regarding hemodynamic change.…

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