The risk for infection in the residual limb increases for patients if an amputation is delayed for more than 5 days after the initial injury, according to a study published in the Journal of Plastic, Reconstructive and Aesthetic Surgery.

“Wound infection is a major complication of post-traumatic extremity amputation and reported to occur in 27-48% of cases,” the authors wrote in the study. “The aim of this study was to identify factors implicated in post-amputation residual limb infection.”

Retrospective study

The study, conducted by researchers at the University of Oxford and Imperial College Healthcare NHS Trust in London, was a retrospective chart review of patients with severe lower limb trauma necessitating an eventual amputation between January 2007 and December 2011 at a level 1 trauma center.

The study included 40 patients with a total of 42 non-salvageable lower limb injuries, and each underwent a mean of 2.7 operative procedures. Of the 42 injuries, there were 32 transtibial amputations, one through-knee amputation and 9 transfemoral amputations.

The researchers found that 25 of the 42 amputations occurred within 5 days of the patient incurring the injury, and of those 25 amputations, six patients developed an infection in their residual limbs. However, in patients with the remaining 17 amputations, which were performed anywhere from 6-30 days after the initial injury, 10 infections occurred.

The chance of infection was also increased when patients underwent more than one debridement. One debridement prior to amputation was performed on 23 of the injured limbs, and of these, five developed an infection. The other 19 injured limbs underwent more than one debridement prior to amputation and 11 developed infections in the residual limb.

“Residual limb infection was significantly more likely when more than one debridement was performed and when amputation was delayed beyond 5 days,” the authors wrote.

Quick action

Based on the study results, the authors recommended that once it has been determined that a limb cannot be salvaged, a decision should be made quickly about amputation in order to reduce the risk for infection in the residual limb and avoid unnecessary surgeries.

“Our results suggest that infection-free amputation is critically dependent on an expeditious decision-making process,” the authors wrote. “Once a limb has been deemed to be non-salvagable, the patient should be counseled that prompt amputation should be performed in order to achieve optimal outcomes.”

However, the authors also note that more than one surgery is often necessary in order to discuss the options with the patient once the first surgical assessment has been conducted.

“It could be argued that, as infection increases with delay to amputation and the number of operative procedures performed, we should advocate only one procedure,” the authors wrote. “However, in practice we have found it is often appropriate to take the patient to theatre for an initial assessment and then plan an amputation as a semi-elective procedure following a discussion with the patient and their family.”

They suggest that as long as the amputation occurs within 5 days of the initial injury, the risk for infection should be mitigated.

“The finding that a delay of up to 5 days can be tolerated without negatively impacting on the risk of post-amputation deep-tissue infection of the stump is useful in that it allows time to prepare the patient for their amputation physiologically and psychologically,” the authors wrote. “To this effect, we enlist the services of a multidisciplinary limb rehabilitation team including patients who have completed their rehabilitation.”— by Megan Gilbride

Disclosure: The authors have no relevant financial disclosures.