Introduction

The startling revelations contained in the Institute of Medicine report To err is human, prompted a realisation that health care is imperfect. The World Health Organization’s World Alliance for Patient Safety highlighted in the ‘Safe surgery saves lives’ campaign that we need to focus our attention on improving the safety culture in the theatre environment.

Unintentional retention of items such as gauze, scalpels, needles or other instruments in a patient after surgery are a significant risk to health, yet the scale of the problem worldwide and in the UK is not fully known.

Terminology

A miscount occurs when the number of swabs counted does not reflect the number of swabs that are actually present, such as with a double count or undercount, and is usually resolved by recounting. A misplaced swab is one that is unintentionally lost on the floor, in the waste, or on the sterile field. A retained swab is a specific type of misplaced swab that is located within the patient’s body cavity, either before the patient leaves the operating room or postoperatively. Retained surgical items may be swabs of a variety of sizes, needles and instruments or parts of instruments or needles. Up to 88% of retained items were associated with a correct count.

Needles were the most commonly miscounted item. Needles are more difficult to locate once they are misplaced as they are small in size. The risk of retained needles, especially small needles, seems to be significantly lower. Whether there is no harm or just a lower incidence of harm, however, is unknown.

One in eight surgical cases involves an intra-operative discrepancy in the count. Most of these discrepancies detect unaccounted for swabs and instruments, which represent potential retained sponges and instruments (RSI). Thus, despite the recognised limitations of manual surgical counts, discrepancies should always prompt a thorough search and reconciliation process and never be ignored.

Unfortunately the terminology around RSI and counting has not been standardised. The terms retained foreign bodies, retained foreign objects, retained surgical equipment, and retained surgical items have all been proposed and used to describe swabs and instruments that are inadvertently left inside a patient at the end of an operation. ‘Retained foreign bodies’ is the most traditional term; however, this terminology can also refer to other retained items such as shrapnel. The most accurate descriptive term is RSI, and we will therefore use this term throughout this review.

Terminology

A miscount occurs when the number of swabs counted does not reflect the number of swabs that are actually present, such as with a double count or undercount, and is usually resolved by recounting. A misplaced swab is one that is unintentionally lost on the floor, in the waste, or on the sterile field. A retained swab is a specific type of misplaced swab that is located within the patient’s body cavity, either before the patient leaves the operating room or postoperatively. Retained surgical items may be swabs of a variety of sizes, needles and instruments or parts of instruments or needles. Up to 88% of retained items were associated with a correct count.

Needles were the most commonly miscounted item. Needles are more difficult to locate once they are misplaced as they are small in size. The risk of retained needles, especially small needles, seems to be significantly lower. Whether there is no harm or just a lower incidence of harm, however, is unknown.

One in eight surgical cases involves an intra-operative discrepancy in the count. Most of these discrepancies detect unaccounted for swabs and instruments, which represent potential retained sponges and instruments (RSI). Thus, despite the recognised limitations of manual surgical counts, discrepancies should always prompt a thorough search and reconciliation process and never be ignored.

Unfortunately the terminology around RSI and counting has not been standardised. The terms retained foreign bodies, retained foreign objects, retained surgical equipment, and retained surgical items have all been proposed and used to describe swabs and instruments that are inadvertently left inside a patient at the end of an operation. ‘Retained foreign bodies’ is the most traditional term; however, this terminology can also refer to other retained items such as shrapnel. The most accurate descriptive term is RSI, and we will therefore use this term throughout this review.

Surgical counting

In January 2009, the National Patient Safety Agency (NPSA) hosted the European launch of the World Health Organization Surgical Safety Checklist and published an alert. The alert requires NHS organisations in England and Wales to implement the surgical safety checklist by February 2010. Surgeons, nurses and operating department assistants were clearly highlighted as being responsible for correct swab and instruments counting.

The surgical count aims to prevent unintentionally retained instruments and swabs after surgery. The surgical count must be a team process, using well established and consistent methods of counting on every occasion.

Counting ensures safety of the patient by early detection of missed items, and alerts the operating team to the problem before occurrence of complications. Swab counting protocols are labour-intensive, and can occupy as much as 14% of the operative time. Surgical counts carried out alongside other tasks, however, should not affect surgery duration and operating theatres time unless a count discrepancy occurs.

The process of swab counting is highly prone to human error or counting discrepancy. It relies on human consistency and accuracy in the surgical environment, which is easily influenced by time pressure, distractions, and unexpected interruptions.

A failure of the counting process, leading to a retained object, exposes the patient to significant risk and is also followed by unnecessary use of hospital resources and negatively affects morale. Under the threat of disciplinary or medico-legal action, staff can experience significant stress while dealing with missing swabs or instruments.

When a discrepancy occurs, the risk of a retained surgical swab or instrument is increased because there is no longer an accurate record of the number of swabs in the field. A recent report suggests that retained items are more than 100 times more likely to occur in a case with a discrepant count.

Risk factors

Unfortunately swab counting can sometimes unintentionally fail, leading to severe consequences for the patient. It is difficult to find specific data on the reason of failure for each particular case. Many factors can contribute to the problem. The counting process has become automatic, which may make practitioners complacent about their attention to detail. This attention to detail may become particularly difficult when theatre environment is full of distractions such as phone calls, theatre practitioners leaving the room for additional supplies, and excessive talking by team members.

Analysis of 9923 surgical records revealed that time of day and length of surgery correlated with an increased incidence of swab and instrument count discrepancies, most of which occurred when multiple theatre teams were involved in the same surgical procedure. The involvement of multiple teams creates an additional layer of complexity and potential fallibility, owing to handover and the potential for communication failures. This may increase the likelihood of count discrepancies.

The accuracy of the counting process depends on factors related to the complexity of the surgery, whether the surgery was carried out on an emergency or urgent basis and factors related to the surgical team’s fatigue and workload. The incidence of retained swabs and instruments is increased in a person with a high body mass index.

Complex surgery carried out with multiple devices and interventions simultaneously in the operating theatre may hinder effective communication between each team member during surgery and create a breeding ground for system failures. These simultaneous activities have the potential to deviate the team away from their normal counting and communication processes. In addition to tracking and counting the surgical items and swabs, activities include assisting in surgical procedures, coordinating the timing of surgery, buffering the unpredicted distractions that may occur (need for additional supplies, answering phone calls). In the short period of time available, this represents a formidable challenge, and renders the process of counting highly vulnerable to mistakes.

Surgery carried out under time pressure, as in emergency situations, may also lead to this problem. A previously published case-control study reported that emergency surgery is nine times more likely to leave retained items than non-emergency surgery. This study also concluded that the risk of RSI increases more than eight times for patients having emergency surgery and over four times for patients having unplanned change in surgical procedure.

In addition, personal attitude and dysfunctional behaviour, such as dismissing an incorrect count without re-exploring the wound, will indeed lead to avoidable adverse events.

All members of the theatre team should share the responsibility of the swab count. In a recent incident where a woman died, the subsequent postmortem examination revealed five retained surgical swabs in the abdominal cavity. The assumptions made by the registered theatre practitioners included an assumption that the surgeon takes full responsibility, the employer has vicarious liability for the employee’s action, and that paperwork takes up too much time. In this case, the jury returned a verdict of death by misadventure with neglect.

Complications

Retained swabs and instruments can result in serious complications and even fatal injuries. In a report of 24 retained items after intra-abdominal surgery, complications presented as perforation of the bowel, sepsis and, in two patients, death. Morbidity was observed in 50% and mortality was almost 10%.

Whenever an incorrect count or discrepancy takes place, the patient can be exposed to additional anaesthetic time and exposure to ionising radiation while looking for retained swabs or instruments. Generally, this will increase healthcare costs owing to unplanned X-rays, extended theatre utilisation, and may lead to cancellation of subsequent patients on the theatre list. Added to this is the time and effort spent in completing incident reporting and investigative processes.

A Gossypiboma, an infrequent surgical complication, is a mass lesion caused by retained surgical swabs. A retained foreign body can trigger a granulomatous reaction. Because gossypibomas can appear years after surgery and have non-specific symptoms, they are usually identified on imaging sequences.

In most cases of unintentionally retained foreign items, an additional treatment (i.e. repeat laparotomy) is often needed and litigation is often provoked. This can drive up the cost of treatment and severely affect the reputation of clinicians and treating institutions.