Blockade of the mental nerve for lower lip surgery as a safe alternative to general anesthesia in two very old patients

Abstract

Purpose: Regional anesthesia is gaining popularity with anesthesiologists as it offers superb postoperative analgesia. However, as the sole anesthetic technique in high-risk patients in whom general anesthesia is not preferred, some regional anesthetic possibilities may be easily overlooked. By presenting two cases of very old patients with considerable comorbidities, we would like to bring the mental nerve field block under renewed attention as a safe alternative to general anesthesia and to achieve broader application of this simple nerve block.

Patients and methods: Two very old male patients (84 and 91 years) both presented with an ulcerative lesion at the lower lip for which surgical removal was scheduled. Because of their considerable comorbidities and increased frailty, bilateral blockade of the mental nerve was considered superior to general anesthesia. As an additional advantage for the 84-year-old patient, who had a pneumonectomy in his medical history, the procedure could be safely performed in a beach-chair position to prevent atelectasis and optimize the ventilation/perfusion ratio of the single lung. The mental nerve blockades were performed intraorally in a blind fashion, after eversion of the lip and identifying the lower canine. A 5 mL syringe with a 23-gauge needle attached was passed into the buccal mucosa until it approximated the mental foramen, where 2 mL of lidocaine 2% with adrenaline 1:100.000 was injected. The other side was anesthetized in a similar fashion.

Results: Both patients underwent the surgical procedure uneventfully under a bilateral mental nerve block and were discharged from the hospital on the same day.

Conclusion: A mental nerve block is an easy-to-perform regional anesthetic technique for lower lip surgery. This technique might be especially advantageous in the very old, frail patient.

Keywords: intraoral; mental nerve block; percutaneous; regional anesthesia; ultrasound.

Figure 1

Anatomy and innervation of the mental nerve. Notes: The mental nerve is a branch of the mandibular branch of the trigeminal nerve and exits the mental foramen (A). The innervation is indicated by the yellow area on the lower lip and chin (B).