Manufacturing defects in polymeric medical devices - Durability and Reliability of Medical Polymers - page 231

The device was tested to standards current to the early 1990s, 5 and
appeared to fulfil all requirements. The device offered a sealed unit so as to
prevent contamination of the central feed line by pathogenic bacteria. The
problem of infection in hospitals is well known, and hospital authorities have
been tackling it by a variety of routes including cleaning and disinfection of
working surfaces, improved staff hygiene and so on. The iV lines need extra
special care because the lines offer direct entry to the body to pathogens,
bypassing the normal defences of the body. Lines carrying nutritional fluids
such as TPN are especially at risk because they offer nutrition to bacteria
as well as the patient.
That the design was faulty emerged later, 6 during a court action brought
by the mother of a premature baby born in a hospital in the south-west of
england in 1995. The premature baby was fed intravenously via a Hickman
line, but suffered infections in the early part of 1996 when the new connectors
started to be used by that particular hospital. According to nurses, doctors
and the mother herself, the connectors kept cracking, and would last no
longer than a day. sometimes brittle cracking was so bad that they had to be
replaced even more frequently. On one occasion, when the baby was being
transferred between hospitals by ambulance, the Hickman line snapped and
the assembly was retained by the mother after surgical removal (Fig. 10.6).
it was to play a central role in the subsequent proceedings. Both of the green
polycarbonate shrouds on the connectors exhibited brittle cracks (Fig. 10.8).
in June 1996, the baby contracted meningitis while cracked connectors
were still in use, and he almost died. it later was found that the little boy
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10.8 Cracked joint in coloured polycarbonate connector.