• implants

I totally agree with all the comments made by Drs Searle, O'Brien and Rowlands in their excellent, detailed letter.1

I agree that Nexplanon^® has not solved the problem of impalpable implants that are due to more deeply inserted implants. I visit the centres that deal with such cases, and the doctors working there confirm that they are seeing just as many cases. Despite the teaching programme there are too many impalpable implants.

I disagree with the proposed procedure outlined in Dr Menon's letter2 although I am sure he has no problems with his technique. We do need to look at the wider use of this excellent product. I can see no point in injecting local anaesthetic (LA) along the proposed tract. The amount injected can vary from 1 to 3 and even 5 ml. It is uncomfortable for the woman, there are no nerves in the subcutaneous tissue and the volume makes it harder to palpate the implant. Think of when we are removing the implant, we inject 0.5 ml LA at our removal site and immediately the end of the implant is less easy to palpate because of the LA. I do not think it makes a tract or that it separates tissue thus making insertion easier. It only fills the tissue with fluid. I also worry that if you anaesthetise the dermis it is possible to have part of the implant resting in the dermis. This would be uncomfortable for the woman. We have inherited this technique from Norplant^® when a trocar and cannula were used; it is not necessary.

I have been involved with Medical Defence Union (MDU) and Medical Defence Shield (MDS) cases where the implant is palpated immediately after fitting but a week later no one can feel the implant. In my opinion the green needle tract and LA were being palpated.

The technique of withdrawing the needle once through the skin and only advancing tenting parallel to the skin when the needle bevel is seen is essential. This step is not in the method recommended by the manufacturer.

I agree that I did not mention non-insertions in my original letter.3 It is difficult to know how non-insertion occurs with the Nexplanon inserter but I have been involved with two such cases.

With non-insertions and the problem of more deeply inserted implants it is worth revisiting training and the method recommended by the implant manufacturer.