Keywords
circulatory assist devices - wound infection - surgery - complications
Introduction
Driveline infection is a serious complication in patients with left ventricular assist
device (LVAD) and a major cause of morbidity and mortality.
Case Description
We report the case of a 65-year-old patient who underwent LVAD implantation (Heart
Ware HVAD [Medtronic, Minneapolis, United States]) due to ischemic cardiomyopathy
in November 2016. Relevant comorbidities include renal insufficiency requiring peritoneal
dialysis.
One year after LVAD implantation, the patient presented in septic state with high
fever and elevated inflammatory parameters (C-reactive protein, 16 mg/dL, leukocytes
17G/L). Staphylococcus aureus could be identified in consecutive blood cultures, as well as from the peritoneal
catheter. During the initial critical period the patients' status deteriorated rapidly
and the patient suffered from serious right ventricular dysfunction, requiring inotropic
support and admission to the intensive care unit. As indicated in [Fig. 1], driveline infection initially presented as massive swelling of the subcutaneous
tunnel with a clean entrance site.
Fig. 1 Initial presentation with infected driveline and peritoneal dialysis catheter.
Therefore, the driveline tunnel was surgically opened and vacuum assisted closure
(VAC) therapy (KCI, Acelity, San Antonio, Texas, United States) was initiated. Simultaneously,
the peritoneal catheter was explanted and peritonitis was proven laparoscopically.
Microbiologically S. aureus was identified at the surgical site and antibiotic treatment consisted of vancomycin,
tigecycline, and meropenem.
The VAC dressing was changed every third day until the swabs returned sterile. After
22 days of vacuum treatment, surgical closure of the wound was performed and transfer
to the normal ward was possible 5 days later. The patient was discharged home after
a total hospital stay of 55 days.
Four months later, the patient was readmitted to hospital due to recurrence of the
driveline infection ([Fig. 2]). In a first step, the wound was reopened, debrided, and negative pressure therapy
was initiated again. After that, further surgical options were evaluated. Since the
patient did not qualify for heart transplantation and neither explantation of the
assist device nor omentum plasty were surgical options, we decided to change the conventional
vacuum therapy to a combination of vacuum therapy with instillation (VAC Veraflo,
KCI Acelity, San Antonio, TX). As detergent, we decided for a 0.04% polyhexanide solution
(Lavasorb, FreseniusKabi, Bad Homburg, Germany) which was installed for 20 minutes
into the wound followed by vacuum treatment for 3 hours. Changes of dressing, as well
as local debridement, as appropriate, was performed in the operation room without
general anesthesia in every 3 days. After 14 days of instillation therapy and sterile
swabs, surgical closure of the wound was performed. Postoperatively, the wound was
treated with epicutaneous negative pressure wound therapy for another 14 days. Antibiotic
treatment was tazobactam/piperacillin and rifampicin. The patient was discharged after
a total hospital stay of 31 days. The patient remains free from signs of infection
for 12 months by now ([Fig. 3]).
Fig. 2 Recurrence of driveline infection.
Fig. 3 Situs 9 months after VAC Veraflo Therapy. VAC, vacuum-assisted closure.
Discussion
Driveline infection is a serious complication after implantation of a LVAD and significantly
contributes to mortality.[1] In patients, who are intended for heart transplantation, driveline infection is
a reason for urgent transplantation, although initial results are inferior.[2]
Further surgical alternatives comprise explant of the infected device, relocation
implant,[3] or omentum plasty.[4] However, all these procedures are major surgical interventions routinely not applicable
for patients in seriously impaired clinical state. In our patient, left ventricular
function did not recover during LVAD therapy and therefore device explantation was
not considered at any point. Furthermore, omentum plasty was not possible because
of the preceding peritonitis, and relocation of the driveline was not considered as
an option due to the lack of space of the infection to the pump. In contrast to the
most usual cases of driveline infections, which are related to the entrance site,
our patient suffered from transperitoneal infection, thus rendering this case unique.
Never before has this been described in the literature, although one case reports
drainage of ascites via the driveline tunnel.[5]
Negative pressure wound therapy has found its way into clinical routine in the 1990s
and indications have been extended ever since. Today, vacuum assisted wound therapy
is a standard treatment for surgical wound infections. In cardiac surgery, VAC therapy
is used for superficial wound infections at the sternum, as well as on graft harvest
sites, deep sternal wound infections, and for postoperative mediastinitis.[6] Even though literature is sparse concerning vacuum treatment of driveline infection,
some cases have been identified, reporting treatment of LVAD infection with VAC therapy.[4]
[7] As our department has a large experience in using VAC therapy, we initially treated
our patient with surgical opening of the tunnel, local debridement, and negative pressure
wound therapy.
Since driveline infection recurred, we had to acknowledge that a new treatment strategy
had to be defined. Therefore and because of the lack of any other surgical option,
we decided to change our treatment strategy to the combination of instillation and
vacuum therapy (VAC Veraflo). The VAC Veraflo is a relatively new therapy, which is
not only used for treatment of conventional wounds but especially in orthopaedic surgery.
Here it has found its place for conservation of infected implants,[8] especially in spinal surgery.
One of the major problems, in the treatment of infection of implants, is the lack
of susceptibility of antibiotics to penetrate the biofilm of bacteria on the implant.
Penetration of biofilm has been reported for anti-infective solutions. Approved products
in Austria include polyhexanide or octenidine. In contrast to the octenidine-based
product, Lavasorb is bottled with an infusion port, thus rendering it most useful
for instillation therapy ([Fig. 4]). The only further case in the literature uses instillation of household bleach
(sodium hypochlorite 0.5%), which is not approved for use in Austria.[9] Furthermore, sodium hypochlorite is, not recommended by the manufacturer, because
it potentially damages the driveline as well as alcoholic solutions do.
Fig. 4 VAC Veraflo system. VAC, vacuum-assisted closure.
Thus, the combination of VAC therapy and instillation of a locally acting antimicrobial
solution seems to be a promising option for the treatment of implant infection.
In our patient, we successfully used the VAC Veraflo therapy with intermittent instillation
of 0.04% polyhexanide solution.
This is the first case to report a successful treatment of recurrent driveline infection
with VAC Veraflo therapy.
Conclusion
In conclusion, we report the first case of successful treatment of driveline infection
with VAC Veraflo therapy with polyhexanide. The combination of negative pressure wound
therapy and instillation of a local antimicrobial solution is a valuable option for
the treatment of patients who lack other surgical options.
