Detection rates of missing microsurgical needles using intra-operative imaging
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Published on: October 16, 2017
Alistair McCombe1, Alicia Heald1, Michael Wagels1,2,3
1Department of Plastic & Reconstructive Surgery, Princess Alexandra Hospital, Brisbane, Queensland, Australia.
Background:
Unintentional retention of foreign bodies in surgery is uncommon but potentially serious. Published data regarding the consequence of retained surgical needles is sparse. We aimed to characterize lost surgical needles at our institution. Secondarily, we aimed to determine whether or not retained microsurgical needles can be reliably detected.
Methods:
Reports of missing surgical needles at our institution were reviewed. Surgical needles of relevant sizes were scattered across an anthropomorphic model at representative anatomical locations. Fluoroscopic images of the field were acquired using two resolution settings. Medical staff in our department attempted to locate needles in these images.
Results:
A total of 46 323 procedures were performed in the main theatres in the 2.5-year period. Sixty-two needles were reported as missing. No patient harm was documented. Needles of chord length 16 mm (5-0) or greater were always detected. High-resolution fluoroscopy improves detection of needles with chord lengths of 9.3 (7-0) or 6.6 mm (9-0). Needles are consistently better detected in the lower limb for needles of chord length greater than 6.6 mm (9-0). Senior observers under ideal conditions can detect 7.1% of smaller needles.
Conclusion:
When a needle is lost during surgery, consider the following before ordering fluoroscopy. Needles of chord length greater than 13 mm (6-0) should be reliably detected whilst 3.8 mm (10-0) needles will not. For sizes in between, ideal conditions for detection may include an operating field in the lower limb, high-resolution fluoroscopy and a senior observer. It may not be necessary or cost effective to identify microsurgical needles with fluoroscopy.
Insights
Lost surgical needles are uncommon but can be serious. Larger needles (>13mm) are reliably detected by fluoroscopy, while smaller ones (<3.8mm) are not. Optimal detection of intermediate sizes depends on imaging resolution and location.
Area of Science:
- Medical Imaging
- Surgical Safety
- Medical Device Technology
Background:
- Unintentional retention of foreign bodies during surgery, though uncommon, poses significant risks.
- Data on the consequences of retained surgical needles is limited.
- This study addresses the characterization and detection of lost surgical needles.
Purpose of the Study:
- To characterize lost surgical needles encountered at an institution.
- To evaluate the reliability of detecting retained microsurgical needles using fluoroscopy.
Main Methods:
- A review of reported missing surgical needles was conducted.
- Surgical needles of various sizes were placed on an anthropomorphic model in anatomical locations.
- Fluoroscopic images were captured at different resolutions, and medical staff attempted needle detection.
Main Results:
- Over a 2.5-year period, 62 needles were reported missing out of 46,323 procedures, with no documented patient harm.
- Needles with a chord length of 16mm or greater were always detected.
- High-resolution fluoroscopy improved detection of needles down to 6.6mm, with better detection in the lower limb for needles >6.6mm.
Conclusions:
- Needles >13mm are reliably detected; 3.8mm needles are not.
- Detection of intermediate-sized needles is enhanced by high-resolution fluoroscopy, lower limb imaging, and senior observers.
- Fluoroscopic detection of microsurgical needles may not be necessary or cost-effective.
