Keywords
closed incisional negative pressure wound therapy - wound healing - wound dehiscence
Introduction
Flaps play a crucial role in the wound healing of critical wounds in which implants,
bone, neurovascular structure, or vital viscera are exposed. Persistent dead space
following flap cover is a frequently encountered challenge. It may lead to a hematoma,
seroma, wound infection, and wound dehiscence. Wound dehiscence may be a devastating
complication. Wound dehiscence in the postoperative period is an important outcome
measure since it impacts the mortality, morbidity, duration of hospital stay.[1] Despite proper surgical technique, patient comorbidities play a significant role
in wound dehiscence.[2] Surgical site infection (SSI), anemia, hypoproteinemia, tobacco abuse, diabetes
are few of the important suboptimal wound factors which contribute to wound dehiscence.[1]
In selected cases like exposed vascular anastomosis/exposed vital structures, complete
optimization of patient’s comorbidities might not be possible before contemplating
a flap cover. In these cases, wound gaping would be a disastrous complication. Closed
incisional negative pressure wound therapy (ciNPWT) has been well described for groin
wounds following vascular surgeries,[3] knee and hip arthroplasties,[4] abdominoplasty incisions,[5] breast surgeries,[6] and abdominal wall reconstruction,[7] morbidly obese woman following cesarean section.[8] To the best of our knowledge application of ciNPWT at flap suture line following
soft tissue reconstructive surgery has not been described previously. In this article,
we share our indications and techniques and outcomes with the ciNPWT.
Materials and Methods
A retrospective analysis (January 2018–June 2019) of patients who underwent ciNPWT
at the flap suture line was included in the study. Selected high-risk patients who
underwent complex reconstruction (pedicled or free flap) were included in the study.
The indications include patients with soft tissue defects and underlying deep incisional/organ
SSI, persistent dead space following flap coverage, chronic osteomyelitis. Patients
in whom NPWT was used for relieving flap congestion were excluded from the study.
Patients also underwent initial debridement and appropriate antibiotic therapy before
flap coverage. NPWT was either applied in the operation theater immediately after
the flap procedure or within 24 to 48 hours following the procedure. NPWT was applied
for patients in whom we anticipated complications of persistent dead space/wound drainage
at the recipient site in spite of an appropriate flap cover. The suspicion of dead
space was based on clinical examination. Whenever the volume of flap was falling short
of the defect’s volume, a persistent dead space was diagnosed. Other indications are
tabulated in [Table 1]. The recipient site wound was closed completely with the flap cover in all the patients.
The skin suturing was done with longer intervals (1.5–2 cm) to facilitate the effect
of NPWT. A 2 to 3 cm wide sponge was cut and applied over the entire suture line adjacent
to the flap and connected to the device set at continuous -100 mm Hg pressure. In
a patient in whom flap cover was done over the repaired femoral artery, the pressure
was set at -50 mm Hg as described by Berger et al.[9] This method allows flap monitoring through the transparent adhesive dressing. The
dressing is changed after 3 to 4 days. NPWT dressing was reapplied if there was a
suspicion of persistent dead space or edematous flap/surrounding skin. In one of the
patients, NPWT was continued for 3 weeks because of persistent lymphorrhea from the
groin wound following femoral artery repair. Once the NPWT was discontinued, regular
dressings were done.
Table 1
Table showing details of patients
|
Patient
|
Etiology
|
Diagnosis
|
Anatomical location
|
Flap
|
Critical issue
|
No. of days of NPWT
a
|
Outcome
|
|
aNPWT, negative pressure wound therapy.
bSSI, surgical site infection
|
|
1.
|
Traumatic paraplegia
|
Sacral pressure ulcer
|
Sacral region
|
Bilateral fasciocutaneous hatchet flap.
|
|
8
|
Good
|
|
2.
|
Trauma
|
Open pneumothorax with osteomyelitis and segmental loss of ribs. Empyema thoracic
with exposed lung parenchyma.
|
Right hemithorax
|
Right pedicled myocutaneous latissimus dorsi flap
|
|
6
|
Good
|
|
3.
|
Scoliosis
|
Exposed spinal implant following scoliosis correction.
|
Back
|
Bilateral myocutaneous trapezius flap, latissimus dorsi flap
|
|
8
|
Good
|
|
4.
|
Trauma
|
Exposed interposition vein graft following repair of femoral artery with large soft-tissue
defect, pelvic fracture.
|
Right groin
|
Contralateral Pedicled myocutaneous anterolateral thigh flap
|
|
21
|
Marginal flap necrosis.
|
|
5.
|
Trauma
|
Exposed implant following fixation of the iliac fracture.
|
Sacroiliac joint region.
|
Gluteal fasciocutaneous hatchet flap
|
|
4
|
Minor wound dehiscence (1 cm).
|
|
6.
|
Traumatic paraplegia
|
Pressure ulcer over the sacral region.
|
Sacral region
|
Gluteal fasciocutaneous hatchet flap
|
|
4
|
Good
|
|
7.
|
Trauma
|
Grade IIIB both bone leg fracture with osteomyelitis and gangrenous extensor compartment
muscles.
|
Right leg
|
Free anterolateral thigh flap
|
-
Dead space,
-
SSI,
-
Osteomyelitis of tibia.
|
8
|
Good
|
|
8.
|
Trauma
|
Soft tissue defect over the right leg with loss of extensor compartment muscles.
|
Right leg
|
Peroneal artery perforator based propeller flap
|
|
4
|
Good
|
|
9.
|
Intramuscular injection sequalae
|
Left hip disarticulation and fillet thigh flap for the exposed pelvic bone.
|
Left hip
|
Fillet thigh flap
|
|
3
|
Chronic discharging sinus due to osteomyelitis of ischium. Healed by local wound care.
|
Results
Nine patients underwent ciNPWT over the flap suture line. The mean age was 32.2 years
(range: 10–48 years). Details of the patients and etiology, critical issues, and duration
of treatment and outcome are tabulated in [Table 1]. The mean duration of the NPWT application was 7.3 days (range: 3–21 days). None
of the patients had major complications. Three of the nine patients had flap-related
minor complications. One patient had marginal flap necrosis and required skin grafting,
one patient had minor wound dehiscence (1 cm) and required secondary skin suturing
and one patient had chronic discharging sinus related to osteomyelitis of ischium,
which subsequently healed with antibiotics and local wound care. None of the patients
had NPWT-related complications such as hemorrhage and infection.
Case Examples
-
Patient 2: A 35-year-old male patient sustained traumatic right open pneumothorax and was referred
to us for management of soft tissue defect over the right chest wall and underlying
rib osteomyelitis, empyema, and exposed lung parenchyma. Following debridement ipsilateral
pedicled latissimus dorsi myocutaneous flap was done to obliterate the dead space
and simultaneous soft tissue cover. The skin and subcutaneous tissues were edematous
due to underlying infection. Though a larger flap would have avoided the tension at
the suture line, we felt it would be cumbersome to skin graft at the flap donor site
in the background of rib osteomyelitis. Following the application of the ciNPWT, the
tension at the suture line gradually decreased and the surrounding edema improved
in 6 days. The flap settled well and the patient had uneventful recovery ([Fig. 1]).
Fig. 1 Image showing (A) right thoracic wound with exposed lung and rib fracture site with osteomyelitis,
(B) following debridement and latissimus dorsi myocutaneous flap (the adjacent skin
shows gross edema due to prolonged soft tissue inflammation due to underlying infection),
(C) NPWT dressing in situ, (D) well-settled flap. NPWT, negative pressure wound therapy.
-
Patient 3: A 10-year-old child was referred for management of wound over the thoracolumbar
region. The patient earlier had spinal instrumentation for scoliosis. The child had
SSI and underwent debridement of the necrosed paraspinal muscles and soft tissue.
The spinous processes were osteomyelitic and there was dead space around the implant
and spinous processes. He underwent V-Y trapezius myocutaneous flap on the left side,
bipedicle trapezius myocutaneous flap and pedicled latissimus dorsi myocutaneous flap
on the right side. Closed incisional NPWT was applied for 8 days. This helped in reduced
need of dressing changes in the postoperative period and untoward effects of dead
space and SSI. The postoperative stay was uneventful ([Fig. 2]).
Fig. 2 Image showing (A) wound over the thoracolumbar spine region with exposure of infected spinal implant
following scoliosis correction, (B) NPWT dressing following bilateral trapezius flaps and latissimus dorsi myocutaneous
flaps, (C) well-settled flaps. NPWT, negative pressure wound therapy.
-
Patient 4: A 45-year-old male patient underwent contralateral anterolateral thigh flap for
coverage of exposed femoral artery repair in the right groin. Challenges in this patient
were, an infected wound bed with dead space and persistent lymphorrhea. In the second
postoperative day, ciNPWT was applied at the flap suture line and continued for 3
weeks. Gradually the exudate had come down. This technique has eliminated the burden
of frequent dressing change due to persistent lymphorrhea. There was marginal necrosis
at the lower portion of the flap which was debrided and covered with a skin graft.
The patient had stable soft tissue cover ([Fig. 3]).
Fig. 3 Image showing (A) contralateral anterolateral thigh flap for exposed femoral artery repair in the
right groin. The wound was complicated by surgical site infection and persistent lymphorrhea,
(B) NPWT wound dressing in situ, (C) well-settled flap. NPWT, negative pressure wound therapy.
Fig. 4 Image showing (A) exposed implant in the sacral region following ORIF, (B) inset of fasciocutaneous hatchet flap, (C) NPWT dressing in situ, (D) well-settled flap. NPWT, negative pressure wound therapy; ORIF, open reduction with
internal fixation.
Discussion
Conventional NPWT is well-known for its role in the management of most of the open
acute and chronic wounds.[10] The direct benefits of NPWT are: (a) maintaining moist and warm environment for
wound healing provided by the semipermeable adhesive dressing, (b) reducing wound
edema by providing pressure gradient between the wound and the suction canister thereby,
draining the fluid from the wound bed and the interstitial space, (c) the wound deformation
leads to approximation of the wound edges together, skin graft/flap apposition to
the wound bed, (d) the wound dehiscence risk is reduced by reduction of lateral strain
at the suture site.[11] The tissue deformation is also a stimulus for the remodeling of tissues.[12] The indirect benefits promoting wound healing are augmented blood supply, reduction
of inflammation, decreased bacterial burden.[13]
The benefits of ciNPWT on surgical incision were first reported a decade ago. The
mechanism of action at the wound site is similar to the conventional NPWT. A recent
review article published in the Cochrane database suggests that the ciNPWT has a role
in the reduction of SSI in wound healing by primary closure when compared with the
conventional wound dressings.[14]
NPWT has shown to be beneficial for closed surgical wounds over the groin following
vascular surgeries,[15] selected patients with risk factors for wound healing complications following knee
and hip surgery.[16] Application of NPWT reduced the incidence of SSI following general and colorectal
surgeries; however, there was no much difference in terms of seroma and wound dehiscence
rates when compared with conventional dressings.[17] NPWT is also helpful in groin wounds complicated by lymphorrea.[18] Incisional NPWT has also shown a positive effect on the healing of primarily closed
defects of superficial circumflex iliac artery perforator flap harvest.[19]
Role of NPWT in preventing bacterial migration into the wound following cardiac surgery
was hypothesized by Grauhan et al.[20] These advantages of ciNPWT are also helpful in a reconstructive surgeon’s practice
in complicated wounds after flap cover.
Routine use of ciNPWT is not cost-effective in all patients who undergo flaps. We
recommend ciNPWT only in selected cases of complex wound reconstructions in which
dead space persists even after flap coverage. The indications can be extended to cases
where lateral wound tension is more than usual at the suture site, lymphorrhea at
the surgical site, patients with risk factors for SSIs. We have used the conventional
polyurethane foam NPWT which is used for open wounds. However, simplified versions
of NPWT are also available. These consist of a single-use battery-driven NPWT device
with a portable canister. The latter is used for wounds that do not have much exudate
in high-risk patients.[21] The technique we used is much cheaper, easily available, and can be applied in patients
with very highly exudating wounds. These are used for single linear incision lines
and not manufactured for application around the flap site. Prophylactic ciNPWT has
been used in few of our patients (patients 1–3) when we anticipated SSI in high-risk
patients. In others (patients 4–9) ciNPWT has been applied in the postoperative period.
In this study, we have utilized NPWT over the flap suture line when the flap was still
healthy. We did not include the cases where NPWT was utilized for salvage of already
compromised flap. When we utilized this technique in the background of osteomyelitis,
adequate debridement was already performed before contemplating flap coverage. However,
in patient 3 who had osteomyelitis of spine, flap coverage was done to ensure antibiotic
delivery and coverage with vascularized tissue. Closed incision NPWT helped in better
wound healing by eliminating the risks of persistent dead space following flap coverage.
The indications of ciNPWT continue to be defined and utilization of this technique
at flap suture line has a lot of scope in day to day plastic surgery practice. The
limitations of the study are small sample size and lack of a comparison group.
Conclusion
Closed incisional NPWT at the flap suture line is a useful wound care modality, beneficial
in patients who undergo complex wound reconstruction. It decreases the untoward effects
of dead space following flap coverage. It is protective against SSI and wound gaping.
Financial Disclosures
Nil.
