PA PSRS Patient Saf Advis 2005 Jun;2(2):17-8.  
Tips from PA Facilities: Enforcing the Time Out and Preventing Retained Foreign Bodies


On occasion, reports submitted to PA-PSRS include the results of the facility’s root cause analysis (RCA) and systems-level solutions for addressing a patient safety issue. In rare instances, the solution to a problem presents itself immediately, and the facility shares this information with PA-PSRS in their original report. More often, though, these “pearls” are submitted in amended reports after a thorough investigation and, in some cases, an RCA.

When facilities share their experience through PA-PSRS, Patient Safety Officers, clinicians, and other healthcare workers can make a difference not only in their own organizations but in healthcare facilities across the Commonwealth. With respect for your contributions and efforts to find innovative solutions, we are happy to share these “lessons learned” with your colleagues throughout Pennsylvania.

Surgical Prep Redesign to Enforce the Time Out

Reports submitted to PA-PSRS of both actual and “near miss” wrong patient, wrong site, and wrong procedure surgeries suggest that the practice of the time out before surgery has become widespread. However, several reports indicate that the surgeon sometimes begins the procedure before the time out is performed.

In one such case, the surgeon started operating on the wrong hand prior to the time out. An amendment to the facility’s original PA-PSRS report indicates that the facility changed their pre-surgery process to minimize the potential for the procedure to begin without a time out: The surgical blade is not attached to the scalpel handle until after the time out is performed.

This same suggestion surfaced in a similar report from another facility that reported a near miss indicating that not all staff members were informed of a new policy requiring the time out to precede the placement of the blade in the scalpel handle.

Notice that this simple suggestion doesn’t add any steps to the process. It doesn’t require any new technology, increase costs, or cause a delay in the procedure. Simply reordering the existing steps provides an additional safety barrier between the patient and the inevitable human error.

This solution is a good example of a “forcing function.” The Agency for Healthcare Research and Quality (AHRQ) Patient Safety Network (PSNet), defines a forcing function as “an aspect of a design that prevents a target action from being performed or allows its performance only if another specific action is performed first.”1 An example cited by PSNet is the elimination of concentrated potassium from floor stock medication cabinets. Forcing functions take different shapes such as “lockins” which prevent exiting until safe; “lockouts” prevent access until conditions are acceptable and; “interlocks” which require a specific order of events or sequencing.2

Other common examples of forcing functions include:

  • CPOE systems that require blood glucose monitoring when insulin is administered or stop an insulin drip (with physician notification) when an NPO order is entered.3,4
  • Medical gas cylinders are accessed by a specific pattern of holes with matching pins from the appropriate regulator. This “Pin Index System” helps ensure that the patient doesn’t get nitrous oxide rather than oxygen by preventing the user from getting the lines crossed.2

A “procedural forcing function” is weaker than a mechanical or physical one, as it relies on a process where human actions are interdependent and thus lacks the mechanics of a failsafe design. Procedural changes fall into this category.2 The practice of not attaching the handle and scalpel until the time out is performed is an example of a procedural forcing function. Other examples include the pre-surgery time out itself and blood product verification by two people.2

The Surgical Towel as Retained Foreign Body

Numerous reports have been submitted to PA-PSRS of discrepancies related to instrument, sharp and sponge counts. Frequently, these case reports indicate that a radiograph was used to confirm the absence of a retained foreign body. Most instruments and sharps are radiopaque. Objects introduced into the body that are not, such as sponges, have radiopaque markers to facilitate identification on a radiograph.

A recent case submitted to PA-PSRS reported identification and removal of a surgical towel left from a procedure that occurred two years earlier. Sterile surgical towels are draped around the wound to minimize contact with the skin. Because they are not intended for use within the wound, they typically do not have radiopaque markers as surgical sponges do. However, occasionally towels are dislodged or are used to cover the wound during intra-operative radiographs or to cover organs, displaced onto the operating surface to facilitate exposure, in order to decrease evaporation from their moist surfaces and prevent desiccation.

The facility reporting this occurrence to PA-PSRS responded to this hazard by changing to radiopaque towels and by taking the following actions to help prevent recurrence:

  • Using radiopaque towels when towels will be placed in a body cavity
  • Including towels used in open wounds as part of routine sponge/instrument counts.

The Association of PeriOperative Registered Nurses (AORN) supports this approach: “If a towel is used for packing, the scrub person must inform the circulating nurse, who must add the towel to the count sheet.  The closing count includes verification that the towel has been removed.   A better alternative is to use commercially available towels that have x-ray detectable strips and are designed specifically for packing.”5

The Veterans Administration’s National Center for Patient Safety also suggests that, “Without exception, all sponges and towels should have radiopaque markers.”6

These actions may help to prevent surgical towels from becoming retained foreign bodies:

  • Incorporating the AORN standards into surgical policies and procedures.
  • Using commercially available towels with radiopaque detectable strips designed specifically for packing.5
  • Independent inspection or exploration of the operative field by the surgeon either routinely7,8 or following procedures that are known for risk of retention of a foreign body, such as emergent cases, those cases with unplanned changes in procedure, and when the patient has a high body-mass index.9 


  1. Patient Safety Net: Glossary. Agency for Healthcare Research and Quality [online]. [Cited 2005 Apr 22.] Available from Internet:
  2. Gaba DM. Thin air. Web M&M: Morbidity and Mortality Rounds on the Web [online]. Agency for Healthcare Research and Quality. 2004 Oct [Cited 2005 Apr 22.] Available from Internet:
  3. Cucina R. The forgotten med. Web M&M: Morbidity and Mortality Rounds on the Web [online]. Agency for Healthcare Research and Quality. 2005 Apr [Cited 2005 Apr 22.] Available from Internet:
  4. Rubin HR, Fajtova VT. Too tight control. Web M&M: Morbidity and Mortality Rounds on the Web [online]. Agency for Healthcare Research and Quality. 2004 May [Cited 2005 Apr 22.] Available from Internet:
  5. Petersen C. AORN journal: September 2001 clinical issues. AORN [online]. 2001 Sep 1 [Cited 2005 Apr 27.] Available from Internet:
  6. Samples C, Dunn E. Reducing the vulnerability of retained surgical sponges. NCPS TIPS (National Center for Patient Safety), Sep/Oct 2004.
  7. Kaiser CW, Friedman S, Spurling KP, et al. The retained surgical sponge. Ann Surg. 1996;224:79-84.
  8. Hyslop JW, Maul KI. Natural history of the retained surgical sponge. South Med J. 1982;75:657-60.
  9. Gawande AA, Studdert DM, Orav JE, et al. Risk factors for retained instruments and sponges after surgery. NEJM 2003 Jan;16(348):229-35.

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