Polyglycolic acid synthetic absorable sutures

Cosmetic outcomes of absorbable versus nonabsorbable sutures in pediatric facial lacerations

OBJECTIVES

We sought to compare the long-term cosmetic outcomes of absorbable versus nonabsorbable sutures for facial lacerations in children and to compare the complication rates and parental satisfaction in the 2 groups.

DESIGN/METHODS

Healthy patients presenting to a pediatric emergency department with facial lacerations were randomized to repair using fast-absorbing catgut or nylon suture. Patients were followed up at 5 to 7 days and at 3 months. Three blinded observers, using a previously validated 100-mm cosmesis visual analogue scale (VAS) as the primary instrument, rated photographs of the wound taken at 3 months. For this noninferiority study, a VAS score of 15 mm or greater was considered to be the minimal clinically important difference. Parents also rated the wound using the VAS and completed a satisfaction survey.

RESULTS

Of the 88 patients initially enrolled, 47 patients completed the study: 23 in the catgut group and 24 in the nylon group. There were no significant differences in age, race, sex, wound length, number of sutures, and layered repair rates in the 2 groups. The observers' mean VAS for the catgut group was 92.3 (95% confidence interval [CI], 89.1-95.4) and that for the nylon group was 93.7 (95% CI, 91.4-96.0), with a difference of the means of 1.4 (95% CI, -5.31 to 8.15), which was less than the minimal clinically important difference of 15 mm (power, >90%). The mean parental VAS score for the catgut group was 86.3 (95% CI, 78.4-94.1) and that for the nylon group was 91.2 (95% CI, 86.9-95.4), with a difference of the means of 4.9 (95% CI, 2.41-7.41), also less than 15 mm. There were no significant differences in the rates of infection, wound dehiscence, keloid formation, and parental satisfaction.

CONCLUSIONS

The use of fast-absorbing catgut suture is a viable alternative to nonabsorbable suture in the repair of facial lacerations in children.

Emergency department repair of hand lacerations using absorbable vicryl sutures

The use of absorbable suture material has a number of potential advantages when compared to nonabsorbable suture. We conducted a 5-year retrospective study of 102 patients with hand lacerations and compared the quality of scar formation and healing in these patients. Those patients who did not have tendon, nerve, or bone injury were included in the study. Lacerations were repaired with either 5-0 Vicryl or nylon. There were no reported complications or infections in any study group patient. The quality of scar, when compared visually and by palpation, was the same at the end of 6 months. In addition, there was no difference in the incidence of scar retraction. We conclude that the use of absorbable suture material is an acceptable alternative in the repair of hand lacerations.

Neomembranes: a concept review with special reference to self-reinforced polyglycolide membranes

Absorbable implants are being increasingly used in various fields of medicine. Important materials for these applications include the polyesters polylactide and polyglycolide. Following implantation of any absorbable device there occurs a proliferation of fibrous tissue, which along with material from the degrading implant forms a composite membranous structure-a neomembrane. Neomembranes can be exploited in guiding tissue regeneration. Success in this respect has been achieved in treatment of bone defects, nerve defects, and periodontal ligaments. Future research may ultimately permit taking advantage of neomembranes in the reconstruction of more complex organs such as the liver. Gaining an understanding of implant characteristics and implant-tissue interaction is essential for further progress in this area.

Subcuticular sutures and the rate of inflammation in noncontaminated wounds

STUDY OBJECTIVE

To determine whether buried, absorbable, subcuticular sutures increase the degree of inflammation in noncontaminated wounds.

DESIGN

Randomized, blinded, prospective trial.

SETTING

Laboratory.

PARTICIPANTS

Eleven Sprague-Dawley rats weighing 300 to 325 g.

INTERVENTIONS

Four wounds were made on each rat. Two wounds on each were closed with three interrupted buried, absorbable, subcuticular sutures 6-0 polyglactin 910 and running 5-0 nylon skin sutures. The other two wounds were closed with running 5-0 nylon skin sutures alone.

RESULTS

Fourteen days after the sutures were placed, the animals were killed, and histologic preparations were made from each wound. Each sample was scored on a scale of 0 to 3 for the presence of inflammatory infiltrates, fibroplasia and capillary proliferation, necrosis, exudates, giant cells, and edema. We determined a total wound score by adding the scores from each category. The mean total wound score was 4.46 +/- 2.92 for those closed with buried, absorbable, subcuticular sutures and 4.91 +/- 2.56 for those closed without buried, absorbable, subcuticular sutures. Using the Wilcoxon rank-sum test, we found no statistically significant difference in mean total wound score of wounds closed with and without buried, absorbable, subcuticular sutures (alpha = .01). The probability of detecting a twofold difference in total wound scores was 60% (beta = .40).

CONCLUSION

Buried, absorbable, subcuticular sutures do not significantly increase the degree of inflammation in noncontaminated wounds.

Selection of wound closure materials

Selection of wound closure materials (sutures, needles, staples, and skin tapes) is presented. The characteristics of commonly used suture materials and needles are discussed as a background for their rational selection and usage. The attributes of staples and sutureless skin closures (skin tapes) are also given and contrasted with those of sutures.

Cuffing techniques in microarterial surgery

Four-stitch microarterial anastomoses reinforced with cuffs of artery, vein, or polyglycolic acid tubing were compared to standard eight-stitch repairs in the femoral arteries of 40 immature rats. The cuffing technique reduced the average repair time by 50% without compromising short- or long-term patency. Restricted vessel growth or anastomotic stenosis did not result from the presence of any of the cuffing materials. Polyglycolic acid tubing performed as well as autogenous cuffs. The cuffing technique helps minimize trauma to the vessel wall by reducing the number of sutures, and its application could significantly decrease the duration of ischemia in multiple digit replantations.

New surgical procedure for management of Peyronie disease

Surgical excision of fibrotic plaques and replacement of the defect by grafts may be necessary in advanced Peyronie disease. Synthetic, absorbable mesh for grafting the defect was used in 6 mongrel dogs. An area of tunica albuginea 1.5 by 2.5 cm was removed from the corpus cavernosum, thus exposing the spongy cavernous tissue. A Dexon mesh of the same dimensions, woven in our laboratory from polyglycolic acid fibers of 308 denier thickness, was sutured to the defect by 3-0 Dexon sutures. The mesh caused hemostasis and the animals' postoperative course was uneventful. Posterection cavernosograms showed no curvature of the penis, bulging of the operative area, or obstruction of the corpora cavernosa. Histologic studies at three weeks, and two, four, and six months after surgery showed complete healing and gradual replacement of the Dexon mesh by fibrous connective tissue.

Cultured rabbit vesical smooth muscle cells for lining of dissolvable synthetic prosthesis

For prosthetic use in genitourinary operations we investigated the feasibility of producing grafts from cultured smooth muscle cells on absorbable synthetic biomaterial. Biopsies of bladder wall muscle without mucosa were obtained from 20 rabbits for culture of smooth muscle cells; cultured cells were examined by light and electron microscopy. Those cells were grown in subculture on a microfiber mesh carrier woven from 35-denier polyglycolic acid fibers. As shown by scanning electron microscopy (SEM), complete coverage of the synthetic fabric was achieved after ten to fourteen days of subculture.

New treatment for urethral strictures

A new operative technique using synthetic, absorbable mesh for grafting a urethral defect was applied in 7 mongrel male dogs. The ventral half of the urethral circumference with its surrounding corpus spongiosum was excised for a length of 3 to 4 cm. A Dexon mesh of the same dimensions, woven in our laboratory from polyglycolic acid fibers, was sutured to the defective area. A perineal urethrotomy was established, and no splints were left behind. Dogs were studied between two and six months. Retrograde urethrography showed that the operative area healed without strictures or irregularities. Intravenous urography showed no back pressure effects, and cultured urine was always sterile. Histologic examination two months after surgery showed that the urothelium was completely healed, without inflammatory changes or disruption. Suburothelial tissues were replaced by dense collagenous connective tissue. The excised corpus spongiosum did not regenerate. After six months, the area of dense collagen described was diminished in size so that the operative area could be hardly identified except by the absence of corpus spongiosum.

Temporal arterial ligation in head and neck surgery with absorbable sutures

Temporary arterial ligation is a useful concept in head and neck surgery for situations dealing with potential recurrent hemorrhage or recurrent vascular neoplasms. In this study, several absorbable sutures, including plain gut, chromic gut, and polyglycolic acid were used to ligate the common carotid artery in dogs. Arterial patency was followed by serial selective arteriograms. Only polyglycolic acid sutures proved to be a reliable material to achieve transient arterial occlusion.

Suturing

Plastic surgeons use sutures for other purposes than the approximation of tissue. They are used to tie over a bolus to close a dead space or maintain a tissue graft in a desired place until it becomes adherent. A bolus of Vaseline gauze over a cotton dental roll is useful (Fig. 7). Sutures may be used to maintain certain tissue relationships until firm scarring will retain this position. Purposeful suturing in contrast to automatic closure of the wound involves the knowledge of wound healing, careful selection of appropriate needle and suture, and the infliction of minimal trauma. Adequate postoperative support of the wound is desirable. Careful critical observation of wounds over long periods of time is instructive.

[Studies concerning the usefulness of catgut, PGA and polyester for abdominal fascia closure (author's transl)]

The abdominal fascia incisions of 133 rabbits were closed either with plain gut, chromic gut, PGA or polyester threads. The breaking strength of the wounds were determined tensiometrically at different time intervals and the tissue was examined histologically. For a three-week period the strength of the abdominal wall depends significantly on the intactness of the threads. PGA produces minimal inflammatory reactions, but loses its strength after a fortnight. Since longitudinal incisions are endangered by severe muscle pull, this material cannot be recommended because of the possibility of wound disruption and the formation of hernias. The loss of strength of catgut plain and catgut chromic starts later. Catgut causes inflammatory reactions within the wound area leading to loss of strength of the sutured tissue. Thus incisions of the abdominal fascia should not be closed with catgut. The non-resorbable suture material polyester shows satisfactory strength and minimal tissue reaction. As long as there is no synthetic suture material with mild tissue reaction and late resorption the fascial closure should be sutured with polyester.

Wound strength in a clinical material

A number of investigations on wound strength have earlier been performed, though mostly in experimental animals and on laboratory tissue; comparisons with human tissue are lacking. In this study, the breaking strength of wounds sutured with two different suture materials, polyglycolic acid (Dexon) and a synthetic polyamid (Supramid) was studied in a human material of 56 patients operated for scoliosis in two stages. Wound thickness and wound length (wound area) were considered in the determination of breaking strength. The breaking strength of a 14-day-old wound was about 57 N/cm2 wound area, a value which is quite comparable to the values obtained in experiments on wound healing in animals, such as rats and rabbits. Those experiments can thus be considered relevant also for human tissue. All wounds healed uneventfully and no difference in strength was noticed in wounds sutured with the two different suture materials.

Mechanical properties of polyglycolic acid sutures in oral surgery

The virgin ultimate strength of polyglycolic acid (PGA) suture material exceeded that of silk or gut, but it decreased significantly after residence in oral tissue of surgery patients. Low-cycle tensile fatigue tests showed that breaking strengths of PGA sutures were decreased appreciably by cyclic loading and by degradation in oral tissue.