Reconstruction of the Distal Leg and Foot Using Free Anterolateral Thigh Flaps in Patients With High-Voltage Electrical Burns

Impact of Microsurgical Reconstruction Timing on the Risk of Free Flap Loss in Acute Burns: Systematic Review and Meta-Analysis

Background

Free tissue transfer is usually considered as a last resort in severe burn cases, when skin substitutes and local flaps are not viable options. Prior studies have demonstrated a free flap loss rate ranging from 0% to 44%. The aim of this study is to identify the ideal timing to perform free flap reconstruction in acute burn-related injuries to minimize free flap loss.

Methods

A systematic review and meta-analysis was performed and reported according to PRISMA guidelines. PubMed, Embase, Web of Science, and Cochrane Library databases were queried. The review protocol was registered on PROSPERO database (CRD42023404478). Three time intervals from day of injury were identified: (1) 0-4 days, (2) 5-21 days, and (3) 22 days-6 weeks. The primary outcome was total free flap loss.

Results

A total of 17 articles met inclusion criteria. The analysis included 275 free flaps performed in 260 patients (88% men, 12% women) affected by acute burn injuries. The pooled prevalence of free flap failure in the three time intervals (0-4 days, 5-21 days, and 22 days-6 weeks) were 7.32% [95% confidence interval (CI): 2.38%-20.37%], 16.55% (95% CI: 11.35%-23.51%), and 6.74% (95% CI: 3.06%-14.20%), respectively.

Conclusions

Free flap reconstruction carries a high risk of failure in patients with acute burn. However, timing of the reconstruction appears to influence surgical outcomes. Free flap reconstruction performed between 5 and 21 days from burn injury had a trend toward higher flap loss rates and should be discouraged.

Free Flap Failure and Complications in Acute Burns: A Systematic Review and Meta-analysis

Background

Severe acute burn injuries represent a challenge to the reconstructive surgeon. Free flap reconstruction might be required in cases of significant critical structure exposure and soft tissue deficits, when local options are unavailable. This study aimed to determine the free flap complication rate in acute burn patients.

Methods

A systematic review and meta-analysis were conducted and reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and registered on the International Prospective Register of Systematic Reviews database (CRD42023404478). The following databases were accessed: Embase, PubMed, Web of Science, and Cochrane Library. The primary outcome was the free flap failure rate.

Results

The study identified 31 articles for inclusion. A total of 427 patients (83.3% men, 16.7% women) accounting for 454 free flaps were included. The mean patient age was 36.21 [95% confidence interval (CI), 31.25-41.16]. Total free flap loss rate was 9.91% [95% CI, 7.48%-13.02%], and partial flap loss was 4.76% [95% CI, 2.66%-8.39%]. The rate of venous thrombosis was 6.41% [95% CI, 3.90%-10.36%] and arterial thrombosis was 5.08% [95% CI, 3.09%-8.26%]. Acute return to the operating room occurred in 20.63% [16.33%-25.71%] of cases. Stratified by body region, free flaps in the lower extremity had a failure rate of 8.33% [95% CI, 4.39%-15.24%], whereas in the upper extremity, the failure rate was 6.74% [95% CI, 3.95%-11.25%].

Conclusion

This study highlights the high risk of free flap complications and failure in acute burn patients.

Implementation and Validation of Free Flaps in Acute and Reconstructive Burn Care

Microsurgical free flap reconstruction in acute burn care offers the option of reconstructing even challenging defects in a single stage procedure. Due to altered rheological and hemodynamic conditions in severely burned patients, it bears the risk of a higher complication rate compared to microsurgical reconstruction in other patients. To avoid failure, appropriate indications for free flap reconstruction should be reviewed thoroughly. Several aspects concerning timing of the procedure, individual flap choice, selection and preparation of the recipient vessels, and perioperative measures must be considered. Respecting these specific conditions, a low complication rate, comparable to those seen in microsurgical reconstruction of other traumatic limb defects, can be observed. Hence, the free flap procedure in acute burn care is a relatively safe and reliable tool in the armamentarium of acute burn surgery. In reconstructive burn care, microsurgical tissue transfer is routinely used to treat scar contractures. Due to the more robust perioperative condition of patients, even lower rates of complication are seen in microsurgical reconstruction.