A surgeon performing a surgical procedure should be able to assume that the instruments used are safe and reliable – particularly if they are new. To ensure the quality of these instruments, the Health Care Standards Policy Committee directed the British Standards Institution to produce requirements for the materials, design, dimensions and other features of surgical instruments. As a result, British Standards (BS), incorporating International Organisation of Standardisation (ISO) standards, were published.1 Each year, large numbers of new instruments are ordered by healthcare facilities across the UK, and those ordering them should be able to rely on these standards. This study reports the results of local quality control by the clinical engineering department of all new instruments supplied to a single NHS trust.
Over a 6-month period between January 2004 and June 2004, all new batches of disposable surgical instruments delivered to the Barts and the London NHS Trust, from a variety of manufacturers, were assessed by three clinical engineers. The suppliers and manufacturers were informed beforehand. Where large numbers of identical instruments were delivered in a single batch, samples of these were examined as follows: 25–49 instruments 50%, 50–74 instruments 30%, 75–99 instruments 20%, and 100+ instruments 15%. In total, 4800 instruments were inspected, where necessary under magnification, for flaws as defined under BS quality assurance requirements.
In total, 730 (15%) instruments failed the inspection. Table 1 shows the flaws that were identified. Figure 1 shows shows33 views of the jaws of vascular clamps: a well-finished instrument on the left, an instrument with machining burrs in the teeth in the middle view and right views. Figure 2 shows a crack in the securing screw of scissors on the left, a crack though the end of the jaws of a needle holder in the middle view, and a major soldering fault in the surface of a wire bending forcep on the right. Figure 3 demonstrates protrusion of a sharp guide pin on gentle closure of tissue forceps.
The commonest fault identified was lack of a maker's mark. BS states that ‘the instrument shall be marked with the name or registered trade mark of the manufacturer or supplier’.1 This may seem like a minor infringement, but in fact it is highly important. If an instrument fails in service, it is essential that the supplier and manufacturer can be notified, so that any potential problem can be rectified, to ensure the safety of the patient and theatre staff. In addition, there is the question of liability and insurance.
The commonest mechanical and structural fault was machining burr debris. BS states that ‘all surfaces must be free from pores, crevices and grinding marks’.1 The fine metallic surfaces of surgical instruments are the product of a number of engineering processes. The shapes and details are initially created by casting and pressing the metal into the required shape, but then finer detail is ground in. In modern, computer-controlled, laser-guided engineering, this should be a straightforward and reliable process, producing an extremely accurate surface, as is shown in the upper view of Figure 1. Sometimes, older methods are used but a fine finish should still be possible, as long as the surface is inspected and machine brush-polished. If this process is incomplete, metallic debris and surface imperfections will remain as shown in the middle view of Figure 1. This may be a problem in a number of ways. First, blood and tissue debris may collect in the imperfect surface. We have traditionally relied on sterilisation procedures to render such debris inert, but there are now concerns that prion disease may survive such processes.2 The metallic fragments may also wear off these surfaces, and remain as microscopic debris in the wound. Sharp burrs on instrument handles may contribute to previously unexplained surgical glove punctures. Although we cannot reference any reported instance of this, BS states that ‘there shall be no sharp edges other than those required by the pattern of the instrument’.1