Anaesthesia: Bilateral guidelines

Sir, much of the controversy over unilateral versus bilateral inferior alveolar and lingual nerve blocks (IANBs) surrounds the safety and efficacy of bilateral anaesthesia even though many surgeons use the procedure for perioperative and postoperative pain relief after day case general anaesthesia with no reports of unwanted effects.¹ The opponents of bilateral IANBs highlight the chances of suffocation or respiratory embarrassment due to lack of tongue control and collection of fluid in the oral cavity.² However, one study concluded that soft tissue trauma was higher in unilateral compared to bilateral subjects and bilateral IANBs have been problem free even in children.³ Extracting both impacted third molars at the same appointment reduces chairside time for patient and clinician, the anxiety associated with a second procedure and lowers healthcare costs as time and materials are considerably less for one-stage procedures. However, there is an absence of guidelines on the use of bilateral IANBs.¹

Informing the patient prior to third molar surgery about the possible chances of the tongue falling back resulting in respiratory embarrassment should be the first step although the surgeon and his/her assistant must monitor this and make quick changes in chair position to avoid problems. Another guideline would be to pass a suture along the tip of the tongue as the entire dorsum of the tongue would be invariably anaesthetised, as this would give the surgical team an additional measure to quickly pull back the tongue in such an instance. Cases of lingual frenectomy are often performed with a suture passed around the tip of the tongue to gain clear access to the lingual frenum. These simple procedures by the clinicians would make bilateral IANBs safer with its various advantages but more work on this topic would help in framing proper guidelines.