The case of the missing implant: the importance of adhering to insertion
guidelines
U. Ernst
Organon Germany, Oberschleiheim, Germany
Introduction: Implanon, a single-rod subdermal contraceptive, releases
68 mg etonogestrel over three years. It was introduced in Germany in June 2000.
This case report describes the incorrect insertion of Implanon, by a
gynecologist trained in the procedure, in Germany in October 2002.
Case description: A 39-year old woman visited her gynecologist for
insertion of Implanon. The insertion was performed whilst the patient was in a
sitting position with the arm hanging downwards. The insertion was made in the
lower third of the upper arm right on the ventrolateral side of the biceps
muscle and not in the recommended area: subdermally in the middle third of the
upper arm in the medial groove between biceps and triceps muscles. Blood flow at
the insertion site was copious during the procedure, especially when the needle
was removed. Following insertion, the implant was not palpable. Attempts made to
localize the implant firstly by ultrasound and then with magnetic resonance
imaging (MRI) were not successful. Additional investigations, performed on the
assumption that the implant might have been inserted intravasally, also failed
to localize the implant. These included MRI of the vessels of the right upper
arm and the right shoulder/clavicle region, the heart and nearby vessels,
echocardiography of the atria and ventricula of the heart, pulmonary artery
angiography, phlebography of the lung veins and the vena cava superior. In
addition to the attempts to locate the implant’s physical presence, detection
of etonogestrel (ENG) was carried out to establish whether the implant was in
the body or not. ENG detection was positive, at a level of 308 pg/ml, which is
in the normal range of an implant in situ. An expert in the field of heart and
lung surgery was consulted as to the possible consequences of an implant
circulating in the thoracic vessel system. He concluded that if the implant had
been carried along with the blood flow, it could eventually become jammed in a
branch of the pulmonary artery, possibly up to a peripheral branch of a lung
segment, where it is unlikely to cause serious damage.
Discussion: This is the first case where the location of a
non-palpable Implanon rod after insertion and positive ENG detection could not
be clarified. Whilst so far there is no direct proof that the implant is in the
vessel system, the procedures followed during this insertion, which deviate from
the official insertion instructions for Implanon, lead to the hypothesis that
the implant was inserted intravasally. This case could and should have been
prevented by the careful following of the guidelines of the package leaflet. The
importance of adhering to those recommendations therefore cannot be stressed
enough.
