A nurse wearing scrubs prepares surgical instruments including swabs.

Retained swabs following invasive procedures: themes identified from a review of NHS serious incident reports

Investigation summary

This investigation explores the patient safety risk of unintended retention of surgical swabs after surgery.

Surgical swabs are sterile pieces of gauze which are used to absorb bodily fluids, such as blood, during a surgical procedure.

The investigation will:

  • explore the factors associated with unintentional retained surgical swab events
  • identify alternative safety controls to reduce the likelihood of foreign objects being unintentionally retained.

The interim report analyses the findings of 31 NHS trust serious incident reports.

Reference event

The reference event involves a patient who had undergone a triple coronary artery bypass graft surgery (heart surgery).

Following their surgery, a chest X-ray identified that a surgical swab had been retained. The patient returned to theatre and the surgical swab was removed. A subsequent chest X-ray identified that a further surgical swab remained in situ, in the same location within the chest. The patient returned to theatre and the second surgical swab was removed.

Read the full report