Case Series On Using Insulin

Pen For Facial Nerve Blocks

For Pain Management

INTRODUCTION

DISCUSSION

This case series presents three distinct cases where facial nerve blocks

(supraorbital, infraorbital, mental) were administered using an insulin

pen (31G x 6mm) to alleviate pain for different facial injuries. Although

studies have explored the advantages of nerve blocks over local

infiltration, there has been limited examination of using a smaller gauge

and shorter needle, such as the insulin pen. While needle size selection

should be individualized based on patient characteristics and clinician

experience, opting for a smaller gauge needle with a shorter length,

akin to an insulin needle, could potentially offer a more comfortable

and less painful experience. This, in turn, may enhance patient

compliance and acceptance of facial nerve block procedures.

Davis Cho DO, Bernice Yu DO, Gustin Reynolds MD, Rabiul Ryan DO

Thomas Jefferson University Hospital

• The following three cases involve separate patients treated at a

Level 1 academic tertiary care and trauma center in Philadelphia,

PA.

• All three patients underwent facial nerve blocks using an insulin pen

(31G x 6mm) containing lidocaine 2% without epinephrine for their

laceration repair.

• All three patients were offered alternate local infiltrates

• The block technique involved palpating anatomical landmarks,

disinfecting the injection site with chlorhexidine, and ensuring

negative aspiration for blood prior to incremental injection.

• Successful analgesia was confirmed after a minimum 5-minute wait.

METHODS

• This case series underscores the versatility and effectiveness of

using an insulin pen for facial nerve blocks in managing a range of

facial injuries, most commonly facial lacerations.

• Needle size decision should be based on careful patient selection

considering individual patient characteristics and clinician

experience.

• Smaller gauge needle with a short length like an insulin needle may

minimize the risk of nerve damage, potential orbital entry during the

infraorbital nerve block via intraoral approach, tissue injury, and

patient discomfort.

• The prospect of a less painful and less daunting needle will provide a

more comfortable experience that encourages patient compliance

and acceptance of facial nerve block procedures. This is especially

important for complex facial injuries, such as lacerations involving

the vermillion border that may require precise approximation that a

local infiltrate may distort.

• Infraorbital nerve may not be ideally targeted with a shorter needle

for deeper nerves, such as the infraorbital nerve via the intraoral

approach.

• The supraorbital nerve may be a suitable target for a smaller needle

due to its average cutaneous depth of 0.75 ± 0.16 (range, 0.5-1.1)

cm.

• Cutaneous depths for infraorbital and mental nerves have not been

extensively reviewed in literature.

Case 1: Supraorbital Nerve

Patient: A 34-year-old male presented

with a left forehead laceration that did

not cross the midline after syncope,

which resulted in hitting his forehead

on a shower railing. Due to the

patient's fear of needles, a left

supraorbital nerve block was

proposed using an insulin pen. The

patient was informed that the nerve

block's success might be unsuccessful

due to the smaller gauge and length of

the needle, potentially necessitating

repeat procedure block with a larger

needle. Despite this, the patient

consented and achieved successful

analgesia with the insulin pen. The

laceration was sutured, and the

patient was discharged with

appropriate follow-up.

Case 2: Infraorbital Nerve

Patient: A 28-year-old male

presenting with left upper lip

laceration across the vermillion border

following a dog bite. An infraorbital

nerve block through an extraoral

approach was attempted to preserve

the integrity of the vermillion border.

After a 5-minute wait, adequate

analgesia was not achieved, prompting

a successful intraoral approach with a

longer gauge needle. The wound was

cleaned with copious irrigation,

wound closed, and the patient was

discharged with oral antibiotics.

Case 3: Mental Nerve

Patient: A 21-year-old female

presenting with right lower lip

laceration across the vermillion border

and right chin after a bicycle accident.

A right mental nerve block was

performed with successful analgesia

allowing better approximation of the

vermillion border and laceration repair.

The patient was discharged with close

follow up.

References

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