General Surgical Strategies to Avoid a Shunt Infection – Adrian Caceres, M.D.

As with any other surgical procedure, complication avoidance and prevention of shunt infection can be related to adequate preoperative evaluation and surgical planning of every step of the procedure to minimize delays and pitfalls. Several of these factors are as follows:

• Match shunt hardware to patient: The shunt system to be implanted should have the smallest profile and the least possible number of shunt components that are appropriate for the patient. In the author’s institution the distal catheter is pre-attached to the valve to minimize manipulation. The author usually places the knots of 3-0 silk facing down or to the side of the valve/catheter junction, as even these materials can erode through the skin of a preterm baby.
• Consider risk factors present: The length of time since birth should be considered, as skin colonization will usually occur after the first 8 hours of life. A patient who has been previously admitted to a NICU and has multiple indwelling lines may be more prone to develop neonatal sepsis and shunt contamination from occult bacteremia. The author usually performs a ventricular tap in this group of patients and, depending on CSF characteristics, will await final cultures before committing to placement of a shunt. Patients who develop hydrocephalus from infectious complications such as bacterial meningitis should also be considered a high-risk group, and CSF cultures from them should always be checked prior to shunt implantation.
• Examine for skin breakage: Patients who have a tracheostomy, a gastrostomy, or a central catheter pose high risk for skin infection and subsequent spread of the infection to the shunt system. Therefore, the trajectory of the catheters should be planned to avoid these areas as much as possible. Skin and scalp ulceration from prolonged decubitus should also be taken in account. Patients who have been treated with multiple wide-spectrum antibiotics can also proceed to develop fungal skin infection, especially in the skin folds of the neck or under tracheostomy ties.
• Protect skin from pressure during surgery: When placing the patient for shunt implantation, place the padding under the head and thorax in such a way to avoid sharp angles when driving the shunt passer. Sometimes an additional small relay incision is preferable to excessive skin manipulation and breakdown.
• Position incisions to avoid shunt: The proximal and distal incisions should be fashioned in such a way as never to overlie shunt hardware, and at least a centimeter should be left between the incision and the shunt.
• Use “no-touch” technique: A “no-touch” technique, where the incision’s skin edges were concealed, a separate set of instruments was used for shunt assembly, and the surgeons’ gloves never directly touched the shunt, significantly decreased the incidence of infection in one study (152). The use of a peritoneal insertion trocar may also help lower the infection rate by reducing the extent of surgical incisions and the operative time.
• Position distal catheter: A distal catheter can be inserted in a single passing from the head to the periumbilical incision. Care must be taken, however, to avoid a tear in the skin from the catheter passer. A catheter passer of appropriate diameter and length must be used, and it must be passed in the subcutaneous tissues to avoid pressure and injury on the dermal layers of the skin. It can sometimes be better to use an extra incision along the path to avoid tearing the skin (153).
• Consider specific risks for skin closure in infants: The skin of very-low-weight patients will not accept skin closure with subdermic reabsorbable sutures. Therefore, nylon can be used in a single layer. Recently, monofilament, resorbable sutures have been used as an alternative to avoid the need for suture removal. In patients who already have a healed umbilicus, the distal catheter can be inserted using these skin folds without increasing the risk of shunt infection.
• Experienced personnel perform surgery: Surgeon experience is fundamental, especially when dealing with preterm children and their fatless delicate skin. At the author’s institution, the procedure follows a protocol that ensures the same steps are taken in every procedure, and the average operative time from skin incision to skin closure is less than 15 minutes.