Postoperative wound dehiscence is defined as a failure in wound healing where previously well-approximated surgical wound edges separate during the early postoperative period.1 This is typically due to factors that contribute to poor wound healing, such as obesity, diabetes, infection, excessive mechanical pressure, and structural instability.2 It remains a compelling concern to surgeons and patients alike, having demonstrated a significant impact on the patient’s long-term morbidity and mortality.3 Furthermore, it also incurs social costs of delayed return to work, increased burden on self-care, and limitations in returning to previous social roles.

Treatment of spinal wound dehiscence is multifaceted. It requires reversal of the underlying medical cause as well as meticulous wound care. Wound care adjuncts such as Incisional Negative Pressure Wound Therapy (INPWT) and Skin Adhesive Tapes (SATs) may be used to support the wound and promote healing.

Negative Pressure Wound Therapy (NPWT) acts by creating a negative pressure to concurrently decrease wound edema and pathogen load while increasing tissue perfusion. Angiogenesis and granulation tissue formation are stimulated under negative pressure directly within the wound.4 This process promotes a healthy vascularized granulation bed for epithelisation. INPWT achieves similar benefits through a negative pressure nonadhesive mesh placed above the wound while relying on sutures or surgical staples to provide mechanical support for skin approximation to expedite the epithelisation process. INPWT is inappropriate for wounds that have unopposed wound edges.

Meanwhile, SATs may be used to provide mechanical support to wounds. They provide strangulation-free support to the wound by loosely opposing superficial wound edges. They are typically used in conjunction with additional subcutaneous and subcuticular sutures to mitigate their limited effectiveness and reliability.5

The authors hypothesized that the individual strengths and limitations of SAT and INPWT would give rise to a complimentary synergistic effect when used in combination with postoperative, poorly healing, and gaping spinal wound dehiscence. The authors report an effective application of SAT-INPWT, (3M™ Steri-Strip™ - 3M™ PREVENA™, USA) to treat a poorly healing midline wound along the thoracic spine in a patient with diabetes and paraplegia. This is an off-label use of the 3M™ PREVENA™ dressing, which is currently indicated for use in surgical wounds that continue to drain after being closed by sutures or staples. The authors partially closed the surgical wound with SATs instead.

CASE REPORT

A 44-year-old Indian male with poorly controlled Type 2 diabetes mellitus (glycated haemaglobin 11.8%) presented to a tertiary hospital with back pain following a fall. This was associated with lower limb weakness and urinary incontinence. Inpatient investigations revealed elevated infective markers (C-Reactive Protein, total white count and erythrocyte sedimentation rate) and methicillin-sensitive Staphylococcus aureus bacteraemia. Magnetic Resonance Imaging of his spine demonstrated posterior epidural abscesses and osteomyelitis of T9 to T11 with thoracic cord compression. He underwent T9 to T11 decompression laminectomy and flavectomy with 2 surgical drains inserted. These drains were removed on postoperative days (POD) 3 and 5. His back pain and elevated infective markers resolved postoperatively, although his lower limb weakness and urinary incontinence did not improve. He was transferred to the community hospital for further rehabilitation due to his ASIA A neurology, and he did not have a caregiver in the country. He was also awaiting transfer to a foreign hospital in his home country, which was significantly delayed due to COVID-19 restrictions.

His operative site was found to have wound dehiscence on POD 14. This was attributed to multiple factors, including his pre-existing Diabetes Mellitus and prolonged supine positioning on a standard mattress while in the community hospital. He had declined the use of an alternating pressure dynamic air mattress due to cost, as he was not eligible for governmental health care subsidies owing to his foreigner status.

His sutures were removed on POD 14, and the wound was serially dressed in antimicrobial silver-containing hydrocolloid dressings (AQUACEL© Ag, Convatec Group, UK). The wound exhibited limited improvement over a period of 29 days without substantial granulation or further epithelialization.

In view of prolonged wound healing and lengthy inpatient stay despite medical optimization for glucose control and nutritional support, the authors applied a combination SAT-INPWT therapy on POD 42 to expedite wound recovery.

The patient had kindly given informed consent for his case to be published and for clinical photographs to be utilized in this report in accordance with the Seventh Revision of the World Medical Association Declaration of Helsinki.

TECHNIQUE The wound was cleaned with chlorhexidine solution and debrided to remove remnant sloughy tissue under local anesthesia. 6×100 mm SATs were placed perpendicularly to the wound to tension it partially closed, leaving a 2 to 3 mm gap at the surface (Fig. 1). The SATs were spaced 1-2 mm apart (Fig. 2A). INPWT dressing was applied above the SATs for 4 days at continuous—125 mm Hg (Fig. 2B). The INPWT output was monitored for features of infection. The authors recommend an acceptable output of no more than 5 to 10 mL of serous discharge. The SAT-INPWT dressing combination was repeated until sufficient wound integrity was reached for regular dry dressings. FIGURE 1:

Cross-sectional illustration of the wound, with SATs applied over the wound with tension to loosely approximate the edges, followed by INPWT dressing applied over SATs, creating a negative pressure space to further reduce the size of the wound.

FIGURE 2:

(A) Placement of SATs (60×10 mm) over wounds with tension to partially oppose the wound edges; (B) Placement of INPWT dressing above SAT.

EXPECTED OUTCOMES

The patient presented in this technique guide had a positive outcome, with the wound demonstrating a notable visual increase in areas of epithelization with reduced depth of dehiscence from approximately 3cm pre-application to 0.5 cm on the 4th-day postapplication (Fig. 3C). Reapplying SAT-INPWT for another 3 days resulted in an almost complete closure and epithelization by 7 days, with a residual cavity of less than 0.1 cm in depth (Fig. 3D). SAT-INPWT was de-escalated to dry self-adhesive absorbent dressings (Mepore®, Mölnlycke Health Care AB, Sweden). Approximately 3 mls of serous fluid were charted on the first day after application of SAT-INPWT, with no output thereafter. At 45 days after SAT-INPWT initiation, his wound was well healed with a good cosmetic appearance. The patient was subsequently discharged from the community hospital after receiving sufficient rehabilitation and went back to his home country without returning for further follow-ups.

FIGURE 3:

(A) Wound packed with hydrocolloid dressing (AQUACEL© Ag) for wound dehiscence occurring on POD 14; (B) Appearance of the wound on POD 42, after 28 days of hydrocolloid dressing. Minimal improvement was observed with regards to the depth of the wound dimensions; (C) Appearance of the wound after 4 days of wound closure with this technique as described; (D) Appearance of wound a further 3 days later, demonstrating rapid and near-complete epithelisation.

While additional studies with a larger sample size and wider range of conditions will be required to support this technique’s use, this technique makes use of the individual strengths of SAT and INPWT to achieve a synergistic effect; SATs would grossly approximate and support the wound while INPWT therapy acts to collapse the wound cavity under negative pressure. This collapse occurs through Pascal’s Law, which states that the pressure of an enclosed fluid is transmitted equally in all directions. In addition, the authors found that the negative pressure generated within the tight seal also enabled the SATs to maintain their adhesiveness to the wound edges and ensured adequate approximation in this moist environment. This synergy of external-mechanical and internal-negative pressure support achieves deep dermal-fascial and superficial cutaneous edge approximation without strangulation and also mitigates pressure from supine positioning. The resultant narrow wound bed allows for easy bridging of epithelisation, less epithelial scarring, significantly reduced duration to recovery, and better cosmetic results. Either therapy applied alone would be ineffective, as SATs are unable to approximate the wound sufficiently independently, while the INPWT is unsuitable for gaping wounds. In addition, this therapy can be applied at the ward level without the need to return to the operating theater, leading to reduced costs and health care utilization. Once applied, the SAT-INPWT may be monitored outpatient according to the practitioner's experience.

COMPLICATIONS

There were no complications seen during the use of this technique. The patient tolerated SAT-INPWT with no back pain, skin irritation, or other discomfort during this therapy. There was also no loss of skin apposition or INPWT leakage. However, theoretical complications of this technique include skin irritation and loss of skin apposition due to insufficient strength from SATs for larger wounds. INPWT leakage may also occur, leading to contamination from nearby sources (such as fecal material for wounds in the lumbar region) and potential infection of the wound.

Limitations for this technique include restricting treatment to medium-sized wounds and at appropriate anatomical locations. In areas such as web spaces, creases, or crevices, a tight INPWT seal may not be achievable due to the existing dimensions of commercial INPWT systems. Nonetheless, the combination of multiple INPWT commercial devices in parallel may be considered for larger or irregularly-sized wounds. Moreover, INPWT may be more costly compared to sutures, although the costs of returning to the operating theater to apply the secondary suture is notably higher.

REFERENCES 1. Shanmugam VK, Fernandez SJ, Evans KK, et al. Postoperative wound dehiscence: Predictors and associations. Wound Repair Regen. 2015;23:184–190. 2. Sandy-Hodgetts K, Carville K, Leslie GD. Determining risk factors for surgical wound dehiscence: A literature review. Int Wound J. 2015;12:265–275. 3. Piper KF, Tomlinson SB, Santangelo G, et al. Risk factors for wound complications following spine surgery. Surg Neurol Int. 2017;8:269. 4. Stannard JP, Gabriel A, Lehner B. Use of negative pressure wound therapy over clean, closed surgical incisions. Int Wound J. 2012;9(Suppl 1):32–39. 5. Rubio P. Use of adhesive tape for primary closure of surgical skin wounds. Intern Surg. 1990;75:189–190.