Wound Complications After Total Hip Arthroplasty: Prevention and Treatment

Introduction

Potential causes of wound drainage or factors associated with wound drainage in total hip arthroplasty (THA) include obesity, use of potent anticoagulants for thromboembolic disease prophylaxis, and high output from a closed suction drain. Surgical irrigation and debridement for prolonged drainage is most effective when performed within 14 days after the index arthroplasty procedure. The routine use of closed suction drainage, which has been associated with increased need for postoperative transfusion, remains controversial. Negative pressure wound therapy (NPWT) is an option for high-risk wounds and as an early intervention for the acutely draining postoperative wound. Early plastic surgery consultation may be required in managing the complex infected wound. The nutritional status of elective total hip patients can be assessed and monitored preoperatively using serum markers such as serum albumin. Erythrocyte sedimentation rate, C-reactive protein, and interleukin-6 can be used to diagnose and monitor treatment progress for acute wound infections in THA. The judicious use of perioperative antibiotics can significantly lower early wound infections. Meticulous wound closure techniques are essential in minimizing fat necrosis and lowering wound infection rates. Minimal incision techniques in THA do not necessarily improve scar cosmesis or reduce the rate of wound issues.

Wound Drainage in Total Hip Arthroplasty

There is no strict definition of “prolonged” or “persistent” wound drainage. Some authors have defined prolonged or persistent wound drainage as wound drainage occurring or continuing 48 hours after the operative procedure. Persistent wound drainage is associated with an increased risk of wound infection following THA. The overall incidence of superficial infection—defined as infection superficial to the fascia lata—after a series of 183 THAs was approximately 17%, while the overall incidence of deep wound infection occurring within 6 weeks of the index surgery was approximately 1%. However, the rate of deep wound infection increased from 1.3% to 50% in cases that had prolonged wound drainage. A retrospective review of 10,000 patients after THA or total knee arthroplasty (TKA) over a 5-year period identified 300 patients with wound drainage occurring greater than 48 hours postoperatively. This persistent wound drainage stopped after 2 to 4 days in 217 (72.3%) of these patients when treated with a standardized protocol of local wound care (cleaning the wound with sterile saline solution followed by application of povidone-iodine solution and oral antibiotics.

Other potential initial treatments of persistent wound drainage after arthroplasty may include the use of incisional NPWT or compression wrapping the wound with a hip spica dressing and/or intravenous broad-spectrum antibiotics. The remaining 83 (27.7%) patients with persistent wound drainage who failed the standardized protocol necessitated surgical irrigation and debridement that was performed 2 to 37 days postoperatively. Deep irrigation and debridement was performed when the deep fascia had not sealed. Surgical irrigation and debridement was successful (i.e., no further intervention) in 63 (75.9%) patients (performed 4–32 days postoperatively). The remaining 20 patients (24.1%) who failed antibiotic therapy as well as surgical irrigation and debridement developed a deep infection that was treated with a two-stage exchange arthroplasty or long-term antibiotic suppression based on their current state of health. Critical evaluation of the 83 patients necessitating surgical irrigation and debridement demonstrated that surgical irrigation and debridement was significantly more successful in patients who underwent this procedure within 14 days from the index arthroplasty. When surgical intervention was delayed longer than 14 days, additional surgical procedures were typically required to eradicate a deep infection ( Fig. 111.1 ). In addition, malnutrition (defined as serum transferrin < 200 mg/dL, serum albumin < 3.5 g/dL, or total lymphocyte count < 1500/mL) was strongly associated with failure of the initial surgical irrigation and debridement. All of the other variables evaluated—including age, gender, surgical blood loss, operative time, and diabetes mellitus—were not statistically significant risk factors for failure of initial surgical irrigation and debridement to treat persistent wound drainage and prevent a deep periprosthetic infection.

It is important to understand the potential causes of and ways to prevent wound drainage, because prolonged postoperative surgical wound drainage has been associated with increased morbidity and longer postoperative hospitalization after THA. A retrospective study involving 1211 THAs identified the risk factors associated with wound drainage 15 days after THA. Obesity (i.e., a body mass index greater than 35), the use of low-molecular-weight heparin (LMWH) for venous thromboembolism prophylaxis, and high closed suction drain output were associated with prolonged wound drainage and a higher rate of postoperative infection (see Fig. 111.1 ). It should be noted that in this study the use of LMWH was associated with earlier postoperative wound drainage compared with the use of either aspirin with intermittent compression devices or warfarin, but the time to a dry surgical wound between LMWH and warfarin equalized on postoperative day 8.

Meta-analysis comparing deep venous thrombosis prophylaxis with warfarin, low-dose unfractionated heparin, LMWH, or aspirin and pneumatic compression found that minor wound bleeding was highest with LMWH and low-dose unfractionated heparin. Because LMWH does not requiring monitoring, its ease of use may outweigh some of the risks associated with a longer time to a dry surgical wound. Low-dose unfractionated heparin was also associated with a higher risk of major bleeding requiring surgical evacuation, and given its lower efficacy for preventing thromboembolic events is not recommended for THA. An administrative database study of early complications after TKA found no significant difference in bleeding-related complications (including wound complications) in the first three months when patients received 81 mg aspirin, warfarin, enoxaparin, or oral factor Xa inhibitors. There are no randomized clinical trials that include factor Xa inhibitors (e.g., fondaparinux) and their effect on surgical wound drainage. Early data therefore suggest that there is no ideal agent for venous thromboembolism chemoprophylaxis to minimize the risk of wound complications.