# Nail Trephination

## Overview

This module describes how to make a small hole or holes in the nail plate to allow for the drainage of a painful subungual haematoma.

## Indications

1. Painful subungual haematoma

## Contraindications

1. Asymptomatic subungual haematoma

2. Nail avulsion or splitting

3. Haematomas older than 48 hours

## Patient information & consent

Always verify your patient’s identity and obtain informed consent before proceeding.

### How do I explain this procedure?

“I am going to use a needle to pierce the nail and allow the blood underneath to drain away. Afterwards, the nail will grow out and the hole will disappear.”

### What can my patient expect?

“Usually, this is a very quick and painless procedure; however, I can give you a series of injections that will numb your finger, but they might hurt more than just making the hole in the nail.”

### What is my patient’s role?

“Let me know if you have any allergies. Fearing blood or needles is normal, but tell me if you have fainted from it. Tell me if you feel any severe pain. Afterwards, keep the area clean and dry and avoid soaking the finger.”

## Preparation

###

### Documentation

1. Patient notes

### Equipment

1. Non-sterile gloves

2. Alcohol-based hand rub

3. Sharps container
   Sharps container

   If a sharps container is not within arm's length, use a kidney dish or other hard container to temporarily hold used sharps and to carry them to the sharps container for disposal.

4. Alcohol swab

5. 18 G needle
   18 G needle

   Nail trephination can also be performed using electrocautery or a heated paperclip or needle, which melts through the nail painlessly. If using an electrocautery device, use povidone iodine to cleanse the skin as alcohol is flammable.

6. Dry gauze dressing & bandage

## Site & Positioning

Position the patient with the finger flat on a surface and within easy reach.

## Procedure

Follow medical asepsis with non-sterile gloves.

1. Perform hand hygiene and don gloves.

2. Clean the nail with an alcohol swab.

3. Hold the needle between finger and thumb and apply the tip to the nail in the centre of the haematoma, distal to the lunula.

4. Roll the needle
   Roll the needle

   If using a heated paperclip or needle, it is not necessary to drill.

   between finger and thumb, applying slight downward pressure to drill into the nail.

5. Once you feel loss of resistance and blood oozes out, stop drilling.

6. Press gently on the fingertip to encourage bleeding.

7. Dress with a dry dressing.

8. Dispose of medical waste safely.

9. Record completion of the procedure in patient notes.

## Troubleshooting

The blood didn’t drain.

Older haematomas may not drain as the blood may have congealed. Some haematomas require more than one hole to drain sufficiently.

## Risks

1. Introduction of infection

2. Pain

3. Nail bed injury
   Nail bed injury

   Drilling into the nailbed is painful, but usually does not affect subsequent nail regrowth, unless the lunula is damaged.

4. Sharps injury to healthcare personnel.

## References

1. Garcia-Rodriguez JA. Canadian Family Physician. Draining a subungual hematoma. Aug 2013;59(8):853.

2. Pingel C, McDowell C. Subungual Hematoma Drainage. [Updated 2021 Jul 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482508/

3. Bharathi RR, Bajantri B. Nail bed injuries and deformities of nail. Indian J Plast Surg. 2011;44(2):197-202. doi:10.4103/0970-0358.85340.

4. Adler M. Chapter 35. Nail Trephination. In: Goodman DM, Green TP, Unti SM, Powell EC. eds. Current Procedures: Pediatrics. McGraw Hill; 2007.