A new resorbable device for ligation of blood vessels - A pilot study

<p>Abstract</p> <p>Background</p> <p>During surgery, controlled haemostasis to prevent blood loss is vital for a successful outcome. It can be difficult to ligate vessels located deep in the abdomen. A device that is easy to use and enables secure ligatures could be beneficial. Cable ties made of nylon have been used for ligation but the non-resorbable material caused tissue reactions. The objective of this study was to use a resorbable material to construct a device with a self-locking mechanism and to test its mechanical strength and ligation efficiency.</p> <p>Methods</p> <p>The device was manufactured by injection moulding of polydioxanone, a resorbable polymer used for suture materials. Polydioxanone with inherent viscosities of 1.9 dL/g and 1.3 dL/g were tested. The device consisted of a perforated flexible band which could be pulled through a case with a locking mechanism. After a first version of the device had been tested, some improvements were made. The locking case was downsized, corners were rounded off, the band was made thicker and the mould was redesigned to produce longer devices. Tensile tests were performed with the second version.</p> <p>The first version of the device was used to ligate the ovarian pedicle in a euthanized dog and to test echogenicity of the device with ultrasound. Compression of vessels of the ovarian pedicle was examined by histology. Both versions of the device were tested for haemostasis of and tissue grip on renal arteries in six anaesthetised pigs.</p> <p>Results</p> <p>The tensile strength of the flexible band of the devices with inherent viscosity of 1.9 dL/g was 50.1 ± 5.5 N (range 35.2-62.9 N, <it>n </it>= 11) and the devices with inherent viscosity of 1.3 dL/g had a tensile strength of 39.8 ± 8.1 N (range 18.6-54.2 N, <it>n </it>= 11). Injection moulding of the polymer with lower inherent viscosity resulted in a longer flow distance.</p> <p>Both versions of the device had an effective tissue grip and complete haemostasis of renal arteries was verified. The device attached to the ovarian pedicle could be seen with ultrasound, and vessel compression and occlusion were verified by histology.</p> <p>Conclusions</p> <p>Tests of functionality of the device showed complete haemostasis and good tissue grip. Devices with a band of sufficient length were easily applied and tightened in tissue.</p

Canine ovariohysterectomy: a survey of surgeon concerns and surgical complications encountered by newly graduated veterinarians

The objective of this study was to document newly qualified veterinarians’ concerns and surgical complications encountered during canine ovariohysterectomy (cOVH) during the first year of general practice. A questionnaire investigating concerns about cOVH procedures was sent to all final-year veterinary students (group 1) enrolled at five UK universities. Participants were later asked to complete a similar questionnaire 6 months (group 2) and 12 months (group 3) after graduation, which involved grading their concern about different aspects of the cOVH procedure and reporting surgical complications encountered after completing three cOVHs. Responses were compared between different time points. There were 196 respondents in group 1, 55 in group 2, and 36 in group 3. Between groups 1 and 2, there was a statistically significant reduction in the respondents’ levels of concern in every aspect of cOVH (p < .05). Between groups 2 and 3, there was no statistically significant change in respondents’ levels of concern in any aspect of cOVH (pb.21). There was a significant reduction in the number of complications encountered by veterinarians in group 3 (39/102, 38.2%) compared to those in group 2 (117/206, 56.8%) (p ¼ .002). Employers should anticipate high levels of concern regarding all aspects of cOVHs in new graduates, and supervision during the first 6 months may be particularly useful