Ambulatory negative pressure wound therapy of subcutaneous abdominal wounds after surgery: results of the SAWHI randomized clinical trial

BACKGROUND: The SAWHI study showed that negative pressure wound therapy (NPWT) reduced treatment time by 7.8 days and had a 20.2% higher wound closure rate, but required a 2.1-day longer hospital stay than conventional wound treatment (CWT). The majority of study participants began treatment in the hospital and were discharged within 42 days. METHODS: As an add-on to a multicenter randomized clinical trial, selected aspects of hospital discharge, outpatient treatment continuation, and subsequent wound closure outcomes are compared between the treatment arms in patients with subcutaneous abdominal wound healing impairment after surgery without fascia dehiscence in the per protocol population. RESULTS: Within 42 days, wound closure rates were higher for outpatients in the NPWT arm than for outpatients in the CWT arm (27 of 55 [49.1%]) for both outpatient continuation of NPWT (8 of 26 [30.8%]) and outpatient CWT after NPWT was finished (27 of 121 [22.3%]). Time to wound closure was shorter for outpatients in the NPWT arm (outpatient transfer with: NPWT Mean ± standard error 28.8 ± 8.0 days; CWT 28.9 ± 9.5 days) than in the conventional treatment arm (30.4 ± 8.0 days). Nevertheless, within 30 study sites with patient enrollment, outpatient NPWT was performed in only 20 study sites for 65 of 157 study participants in the treatment arm. CONCLUSIONS: Outpatient NPWT of postsurgical abdominal wounds with healing impairment is feasible and successful and should be encouraged whenever possible. Study site specific avoidance of outpatient NPWT emerges as an additional reason for the prolonged hospitalization time. Trial Registration ClinicalTrials.gov Identifier NCT01528033. Date of registration: February 7, 2012, retrospectively registered SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12893-022-01863-x.