Although birth by caesarean section (CS) is a common procedure, there are a number of potential complications, of which one is surgical site infection (SSI) (Gould, 2007; Wloch et al, 2012). Mortality due to severe maternal sepsis has increased in the UK and is now the leading cause of direct maternal death (UK Obstetric Surveillance System, 2015). Health-care practitioners should be aware of the risk of sepsis following birth by CS. Midwives, doctors and other health professionals need to ‘think sepsis’ and aim to reduce the risk of women developing sepsis following CS (MBRRACE-UK, 2014).
Aim
The type of wound dressing used following CS, and the length of time that the wound dressing is left in place, may contribute to an increased risk of infection. Lancashire Teaching Hospitals NHS Foundation Trust decided to complete an audit to identify the number of women who developed an SSI following birth by CS. The audit would also identify how many of these women required readmission to hospital for treatment for the SSI.
Method
A selected team of midwives was approached to complete the audit. It was decided that the audit was to be completed as a retrospective audit. A 6-month audit period was used to ensure that there were sufficient data to support any change in practice. All the case notes of women who had given birth by CS during this time period were reviewed—a total of 505 case notes.
A multidisciplinary approach was used when completing the audit. The infection prevention and control (IPC) team worked together with the audit team. The IPC team had access to a database, which recorded all wound swabs taken by staff caring for women. The team could also identify the results of the swabs, together with what treatment was required to treat the infection.
Limitations
The audit team only audited case notes from a 6-month period, which would limit the data obtained. The list of case notes to be audited was obtained using a computerised electronic record completed by the midwives following birth. This system relies on midwives completing the birth record accurately and documenting the type of birth the woman had. There is a possibility that the birth record may be incorrectly documented as a CS when in fact birth was vaginal, although this is unlikely to happen due to further review of the case notes by the audit team.
Results of the audit
A total of 263 elective CS case notes and 242 emergency CS case notes were audited. The audit team completed the audit proforma designed specifically for this audit. The team found a total of 63 confirmed infections from wound swabs taken from the site of the CS, giving the overall SSI rate for women with CS at 12.5% (Table 1). There was minimal difference between the SSI rates for elective or emergency CS. The overall rate is higher than the 9.6% found by Wloch et al (2012). Only one woman was readmitted to hospital for SSI treatment during the 6-month audit period, which is a reassuring finding for this NHS Trust.
| Total number of case notes reviewed | 505 |
| Number of confirmed infections | 63 |
| Percentage of confirmed surgical site infections | 12.5% |
A finding from the audit results demonstrated that women who had their CS wound covered for a longer period of time were less likely to develop a wound infection. The Trust currently uses a non-woven dressing, which is removed approximately 24 hours after the CS, as recommended by the National Institute for Health and Care Excellence (2011). Part of the case note audit looked at the time of the CS and compared this to the date and time the wound dressing was removed. Some women, for various reasons, had the wound dressing in place for longer than the recommended 24 hours. The audit found that these women were less likely to develop an SSI.
Trial
Following the audit, it was decided that a trial was to be commenced. The trial involved leaving the wound dressing in place for 5 days, using two different types of waterproof interactive dressings. The first dressing was Opsite Post-Op Visible and the second dressing was Mepilex Safetac. The cost of the two dressings was similar. Choosing two dressings that are similar in cost ensured that the decision to implement one of the dressings was not based on cost alone, but with best practice being put ahead of financial gain.
The trial for each dressing was commenced on a Monday morning and was planned to finish on the Sunday evening of the same week. During the first week, 20 women had a CS and the Opsite Post-Op Visible was used for every CS. Consent was gained from the women and a proforma was completed for each woman. The woman was approached prior to discharge home, to see if any problems had arisen with the wound dressing. The proforma was then returned to the audit team following discharge from the community midwife. The second trial was completed the following week, involving 17 women, with Mepilex Safetac dressing used to cover the wound.
Results of the trial
The trial of the second dressing involved fewer women; however, it was clear that the Mepilex Safetac dressing was not as successful as the Opsite Post-Op Visible. Three of the Mepilex dressings had come off within 24 hours of being applied and four more dressings had come off before the full 5-day period was over.
The results demonstrated that two women developed SSIs during the trial—one with each type of dressing (Table 2). There were no postnatal readmissions during the audit period. This is excellent news for both wound dressings, as it appears that covering the wound for longer has decreased the risk of developing a SSI. However, the audit results are difficult to compare as some of the Mepilex Safetac dressings did not remain in place for the full 5 days. The Trust will also have to consider that the number of women participating in the trial was low, compared with the initial audit. A further audit with a larger number of participants should be taken to ensure that the results match the initial audit.
| Type of dressing | Opsite Post-Op Visible | Mepilex Safetac |
|---|---|---|
| Women using dressing (n=37) | 20 | 17 |
| Confirmed surgical site infections (n=2) | 1 | 1 |
Change in practice
Following the completion of the audit, the Trust has taken a proactive step to try to reduce the rate of infections. The Trust has decided to use the Opsite Post-Op Visible dressing for all women having a CS, with an aim to re-audit the rates of SSI from CS within a 12-month period, to ensure that the rate of CS wound infections remains low.