Advantage of absorbable suture material for pulmonary artery ligation

Pressure-driven spreadable deferoxamine-laden hydrogels for vascularized skin flaps

The development of hydrogels that support vascularization to improve the survival of skin flaps, yet establishing homogeneous angiogenic niches without compromising the ease of use in surgical settings remains a challenge. Here, pressure-driven spreadable hydrogels were developed utilizing beta-sheet rich silk nanofiber materials. These silk nanofiber-based hydrogels exhibited excellent spreading under mild pressure to form a thin coating to cover all the regions of the skin flaps. Deferoxamine (DFO) was loaded onto the silk nanofibers to support vascularization and these DFO-laden hydrogels were implanted under skin flaps in rats to fill the interface between the wound bed and the flap using the applied pressure. The thickness of the spread hydrogels was below 200 μm, minimizing the physical barrier effects from the hydrogels. The distribution of the hydrogels provided homogeneous angiogenic stimulation, accelerating rapid blood vessel network formation and significantly improving the survival of the skin flaps. The hydrogels also modulated the immune reactions, further facilitating the regeneration of the skin flaps. Considering the homogeneous distribution at the wound sites, improved vascularization, reduced barrier effects and low inflammation, these hydrogels appear to be promising candidates for use in tissue repair where a high blood supply is in demand. The pressure-driven spreading properties should simplify the use of the hydrogels in surgical settings to facilitate clinical translation.

A survey of current practices and influences on the choice of suture material, pattern and size used in commonly performed procedures in UK small animal veterinary practice

Objectives

A survey of UK veterinarians was conducted to determine factors influencing suture choice and current suture practice for common surgical procedures.

Methods

An online survey was designed and the survey was sent to central practice emails obtained from the 2011 Royal College of Veterinary Surgeons (RCVS) practice database.

Results

Two hundred and thirty-nine surveys were completed (203 with no additional postgraduate qualifications (NAQ), 16 with RCVS certificates and 19 with diplomas). Forty-seven per cent of veterinary surgeons reported they would benefit from Continued Professional Development (CPD) pertaining to suture material selection and techniques. The NAQ group ranked practice policy, colleague influence, cost of suture material and undergraduate teaching significantly greater than diploma and certificate holders. The widest differences between suture material selection, pattern and size were identified when comparing diploma holders and the NAQ group. Diploma holders tended to choose smaller sized suture material when compared with the NAQ group.

Clinical significance

In conclusion, postgraduate qualifications have a significant effect on the choice, pattern and size of suture material used for many routine surgical procedures. Findings suggest that further postgraduate training pertaining to the selection and use of suture material is worthwhile and improved guidance of choice of suture material for commonly performed surgical procedures may be beneficial.

Importance of absorbable surgical sutures for the prevention of stitch abscess after surgery in patients with oral squamous cell carcinoma

Background

To elucidate the significance of absorbable surgical sutures in the occurrence of stitch abscess after surgery in patients with oral squamous cell carcinoma (SCC).

Material and Methods

The subjects were 251 patients who underwent excision and/or reconstruction and/or neck dissection for oral SCC using absorbable surgical sutures. Detection rates and characteristics of patients with stitch abscess were retrospectively evaluated by comparing between our present and previous data.

Results

There was only one stitch abscess among the 251 patients. A significant difference in the incidence of stitch abscess was found between the present data and our previous data. Of course, no significant correlations were found between the occurrence of stitch abscess using absorbable surgical sutures and the various factors seen in our previous analysis.

Conclusions

A complete switch of surgical sutures from silk to absorbable surgical sutures is needed for surgery in patients with oral SCC.

Key words:Stitch abscess, oral cancer, occurrence, absorbable surgical sutures, silk suture.

Simultaneous stapling of the lobar bronchus and pulmonary artery: is it actually dangerous?

We performed a left caudal lobectomy on a 3-month old male swine. During the lobectomy, the lobar bronchus and pulmonary artery were stapled simultaneously using an endostapler. According to a postmortem examination 42 days after the operation, the stumps were surrounded by granulation tissue with prominent accumulation of inflammatory cells. With respect to the bronchus, the stapled tissue remained as it was just after stapling, without degradation of the cartilage, smooth muscle or epithelial layers. In contrast, with respect to the pulmonary artery, the stapled tissue disappeared, which resulted in the formation of a new vascular stump with recruitment of a new adventitial layer and fibrotic tissue. Therefore, despite the simultaneous stapling, the vascular stump was separated from the bronchial stump. Our results suggest that the process of stump healing after stapling of the bronchus is different from that after stapling of the pulmonary artery: bronchial stump healing consists of extraluminal covering of the fibrotic tissues, while pulmonary arterial stump healing consists of intraluminal reformation of the intima and media. On the basis of the results, we believe that a bronchovascular fistula will not develop after simultaneous bronchovascular stapling unless the anterior wall of the bronchus has fallen away due to major stump necrosis.

Quantitative evaluation of contrast-enhanced ultrasonography in the diagnosis of chronic ischemic renal disease in a dog model

Objectives

The aim of this feasibility study was to prospectively explore in a dog model of chronic ischemic renal disease (CIRD) the hypothesis that real-time contrast-enhanced ultrasonography (CEUS) can quantitatively evaluate the early perfusion changes of renal cortex.

Materials and Methods

In this animal care and use committee-approved study, the model of CIRD was carried out in healthy dogs (10.0∼12.0 kg, n = 5), by placing the Ameroid ring constrictors on the distal portion of right renal artery through operation. CEUS monitoring of right kidney perfusion was performed by intravenous bolus injection of 0.6 ml Sulfur hexafluoride filled microbubbles (SonoVue; Bracco S.P.A., Milan, Italy) every week after operation. The slope rate of ascending curve (A) and descending curve (α), area under curve (AUC), derived peak intensity (DPI), and time to peak (TTP) were measured in renal cortex using commercial quantification software (Q-LAB version 6; Philips Medical Systems, Bothell,WA,USA). The sensitivity of CEUS was compared with blood serum urea nitrogen (BUN) and serum creatinine (SCr) level.

Results

With the progression of CIRD, dogs showed delayed enhancement and perfusion in renal CEUS curve. Earliest significant changes happened 4 weeks after operation on DPI and TTP which changed from 13.04±2.71 to 15.58±4.75 dB and 9.03±2.01 to 10.62±6.04 sec, respectively (P<.05).

Conclusions

CEUS can display the perfusion changes of CIRD in the early period.