Remote diagnosis of surgical-site infection using a mobile digital intervention: a randomised controlled trial in emergency surgery patients

Abstract

Surgical site infections (SSI) cause substantial morbidity and pose a burden to acute healthcare services after surgery. We aimed to investigate whether a smartphone-delivered wound assessment tool can expedite diagnosis and treatment of SSI after emergency abdominal surgery. This single-blinded randomised control trial (NCT02704897) enroled adult emergency abdominal surgery patients in two tertiary care hospitals. Patients were randomised (1:1) to routine postoperative care or additional access to a smartphone-delivered wound assessment tool for 30-days postoperatively. Patient-reported SSI symptoms and wound photographs were requested on postoperative days 3, 7, and 15. The primary outcome was time-to-diagnosis of SSI (Centers for Disease Control definition). 492 patients were randomised (smartphone intervention: 223; routine care: 269). There was no significant difference in the 30-day SSI rate between trial arms: 21 (9.4%) in smartphone vs 20 (7.4%, p = 0.513) in routine care. Among the smartphone group, 32.3% (n = 72) did not utilise the tool. There was no significant difference in time-to-diagnosis of SSI for patients receiving the intervention (-2.5 days, 95% CI: -6.6-1.6, p = 0.225). However, patients in the smartphone group had 3.7-times higher odds of diagnosis within 7 postoperative days (95% CI: 1.02-13.51, p = 0.043). The smartphone group had significantly reduced community care attendance (OR: 0.57, 95% CI: 0.34-0.94, p = 0.030), similar hospital attendance (OR: 0.76, 95% CI: 0.28-1.96, p = 0.577), and significantly better experiences in accessing care (OR: 2.02, 95% CI: 1.17-3.53, p = 0.013). Smartphone-delivered wound follow-up is feasible following emergency abdominal surgery. This can facilitate triage to the appropriate level of assessment required, allowing earlier postoperative diagnosis of SSI.

Fig. 1. CONSORT flow diagram.

The patient flow for the TWIST trial.

Fig. 2. Time-to-diagnosis (days) of surgical-site infection (SSI).

The time-to-diagnosis (days) of patients who were diagnosed with SSI within 30-days as (a) time-to-event plot (b) boxplot.

Fig. 3. Comparison of patient experience of postoperative care between trial arms.

Three measures of patient experience compared between trial arms with regards to the (a) ease of access of advice, (b) speed of access of advice, and (c) usefulness of advice. This displaysthe percentage (%) of patients who reported positive responses to these measures (“agree” or “strongly agree”), and provides an effect estimate (odds ratio [OR]) of the odds of positive response in patients receiving the smartphone intervention, compared to routine care.

Fig. 4. Patient experience of those who used the smartphone tool.

The five measures of patient experience in patients who used the intervention (a) ease of tool use, (b) understandability of tool, (c) ease of image upload, (d) helpfulness of advice, and (e) Feasibility of advice. This has been stratified by adherence: either full adherence (completion of all three routine response requests in the follow-up period) or partial use (any usage of the tool that did not meet the criteria of full adherence). These plots display the percentage (%) of patients who reported positive responses to these measures (“agree” or “strongly agree”) and provides an effect estimate (odds ratio [OR]) of the odds of positive response in patients who displayed full adherence, compared to partial adherence.

Fig. 5. TWIST Trial definitions and processes.

a The intervention schemata which demonstrates the process of the digital health intervention. This outlines how the clinical team was alerted whenever a patient response was submitted (whether patient-initiated or a routine request on days 3, 7, of 15), and the communication to patients when a clinical decision on the risk of surgical-site infection was made. This also depicts the criteria for assessing secondary outcomes in the smartphone arm: b how adherence to routine requests for completion of smartphone tool was determined, and c how diagnostic accuracy of clinical assessments of responses submitted using the smartphone tool was determined.