Treatment of grade 4 renal stab wounds with absorbable fibrin adhesive bandage in a porcine model

PURPOSE: In a porcine model we evaluated the efficacy of the absorbable fibrin adhesive bandage and other novel fibrin products for treating major renal stab wounds. MATERIALS AND METHODS: In commercial swine we produced an almost lethal, grade 4 renal stab wound via a 3.5 cm. sagittal, centrally located, through-and-through laceration. Each pig then received treatment in random fashion, including conventional oversewing of capsular defects with absorbable gelatin sponge and horizontal mattress sutures in 6, external absorbable fibrin adhesive bandage that was pressure held for 60 seconds in 6, external and internal absorbable fibrin adhesive bandage that was applied externally, inserted into the renal defect and pressure held for 60 seconds in 6, liquid fibrin sealant that was placed in the laceration and held for 60 seconds in 8, fibrin foam that was applied in the same manner as liquid fibrin in 5 and closing of the peritoneum over the lacerated kidney without further treatment in 6. Blood loss and time to hemostasis were recorded. Animals were sacrificed at 6 weeks to evaluate the injured renal unit. RESULTS: Compared with conventional therapy the absorbable fibrin adhesive bandage applied externally alone or externally and internally resulted in significantly less bleeding and significantly less time to hemostasis (p <0.001). Liquid fibrin and fibrin foam did not reliably achieve hemostasis. Postoperatively computerized tomography and histological sectioning suggested that the absorbable fibrin adhesive bandage results in a stable, durable clot and healing is at least as successful as with conventional treatment. CONCLUSIONS: The absorbable fibrin adhesive bandage appears to be a safe, rapid means of renal salvage after injury.     

Mechanical strength in rat skin incisional wounds treated with fibrin sealant

The biomechanical strength of skin incisional wounds of rats treated with fibrin sealant was assessed by in vitro determination of maximum tensile strength and relative failure energy. Wounds adapted without application of fibrin sealant served as control. Both types of wounds were fixed with surgical tape for the first 8 days of healing. Measurements were performed after 0, 2, 4, 8, 20, and 42 days of healing. After 2 days of healing, wounds treated with fibrin sealant possessed increased maximum tensile strength and relative failure energy. This increase corresponds to the initial strength of the fibrin sealed wounds (0 day values). After 4 and 8 days of healing, no differences were found between the sealed and unsealed groups. After 20 days, the pattern had changed showing increased tensile strength and relative failure energy in wounds not treated with fibrin sealant. A similar trend was reported after 42 days of healing. In both sealed and control wounds, an increase in strain at maximum stress during healing was most pronounced in the first 8 days. After 2 days of healing the strain at maximum stress was increased in wounds treated with fibrin sealant.     

Thrombogenic effects of a nonthrombin-based fibrin sealant compared with thrombin-based fibrin sealant on microvenous anastomoses in a rat model

The efficacy and safety of tissue adhesives needs to be clearly defined. A thrombin-based preparation of fibrin sealant has recently been shown to have deleterious effects on microvascular anastomoses in an animal model. The authors found that fibrin sealant constructed with a high concentration of bovine thrombin (1,000 IU per milliliter) was detrimental to microvascular patency when applied to the anastomosis in a rat free flap model. The microvenous anastomosis had the highest rate of thrombosis and failure in this model. A nonthrombin-based fibrin sealant has recently become available for experimental investigation. This study examined the thrombogenic effect of this nonthrombin-based fibrin sealant on microvenous anastomoses in a rat free flap model compared with the effect of traditionally prepared fibrin sealant with varying concentrations of thrombin. The conclusions reveal that flap survival with application of the nonthrombin-based fibrin sealant to the anastomosis was comparable with flap survival of the control animals. Flap survival with application of the traditionally prepared thrombin-based fibrin sealant was also comparable with flap survival of the control animals when a concentration of 500 IU per milliliter of thrombin was used. However, flap survival decreased significantly (p <0.005) when a concentration of 1,000 IU per milliliter of thrombin was used in the construct of the fibrin adhesive. These results support the previous findings of the harmful effects of thrombin when used in high concentrations and applied to the microvenous anastomosis of this free flap model. Moreover, this initial investigation with a nonthrombin-based fibrin sealant did not show any deleterious effects on the microvenous anastomosis compared with control animals.     

Evaluation of fibrin sealant for biologic mesh fixation at the hiatus in a porcine model

Background

The ideal method to secure biologic mesh during laparoscopic hiatal hernia repair remains uncertain. Suture or tack fixation can be technically difficult, and serious cardiovascular complications have been reported. Fibrin sealant (FS) offers a potential solution to this problem. We hypothesized that FS provides comparable mesh fixation to suture repair during laparoscopic mesh hiatoplasty.

Study design

Using a porcine model, laparoscopic hiatal hernia repair was performed with suture reapproximation of the crura and reinforcement with an acellular porcine dermal matrix. Prior to repair, animals were randomized to mesh fixation with sutures (S) or FS. After 30-day survival, an esophagram was performed, the diaphragm harvested, and mesh position, fixation, and incorporation were evaluated histologically and biomechanically using a T-peel test.

Results

Twenty (10 S and 10 FS) laparoscopic hiatal hernia repairs were performed. Total operative time was significantly less in the FS group (74.7 versus 127.0?min, p?<?0.01). There were no instances of mesh migration in any animal. Mean peel force did not differ significantly between the S and FS groups (0.21 vs. 0.18?N/mm, respectively; p?=?0.49). There was no significant difference in cellular repopularization or inflammatory changes around the mesh.

Conclusions

Fibrin sealant offers a reasonable alternative to suturing biologic mesh during laparoscopic hiatal hernia repair with equivalent mesh fixation. At 30 days it provides adhesive strength similar to suture fixation, while significantly reducing operative time.     

Laparoscopic fixation of biologic mesh at the hiatus with fibrin or polyethylene glycol sealant in a porcine model

Background  

The objective of this study was to determine the acute and chronic fixation strengths achieved by fibrin or polyethylene glycol (PEG) sealants to secure biologic mesh at the esophageal hiatus in a porcine model.     

The co-application of sprayed cultured autologous keratinocytes and autologous fibrin sealant in a porcine wound model.

We have explored the potential for cultured autologous keratinocytes to form an epidermis when delivered as a spray intermixed with autologous fibrin sealant. Twelve full-thickness wounds in Large White pigs (six wounds in each of two pigs) were isolated from the surrounding skin by 4 cm diameter polytetrafluoroethylene chambers, and grafted with Integra artificial skin (Ethicon). Autologous fibrin sealant was produced 10 days later, using an automated processor unit (Vivostat System, ConvaTec, Bristol Myers Squibb), from 120 ml of autologous citrated blood taken 30 min before keratinocyte application. Nine wounds were sprayed, using a Vivostat System automated applicator unit, with a mixture of the sealant preparation and freshly trypsinised cultured autologous keratinocytes in growth medium, at a density of 1-3 x 10(5) cm(-2). Three control wounds were sprayed with the same mixture without cells. The sealant-cell mixture polymerised and adhered to the wound surface immediately. Histological analysis of biopsies taken following sealant-cell application showed that isolated spherical keratinocytes were distributed throughout the sealant at between 3.1 x 10(4) cm(-2) and 7.6 x 10(4) cm(-2). After 4 days discreet colonies of keratinocytes were observed on the wound bed. At 14 days a multi-layered undulating epidermis was formed, punctuated by sporadic epidermal cysts; the mean area of epithelium was 50.1% (s.d. = 19.7%, n = 9). There was no epithelium in the controls (s.d. = 0, n = 3). The difference was statistically significant (P=0.016). This study suggests that co-sprayed cultured keratinocytes and autologous fibrin sealant may be an effective means of delivering epithelial cells to assist wound healing.     

Conservative treatment of abdominal stab wounds with omental protrusion

Two cases of abdominal stab wounds with omental protrusion treated conservatively are presented. Omental protrusion in a patient without signs of shock or peritoneal irritation is not an absolute indication for explorative laparotomy.     

Cultured keratinocytes in fibrin with decellularised dermis close porcine full-thickness wounds in a single step

The purpose of this study was to assess the feasibility of combined keratinocyte and dermal scaffold transplantation performed in a single step for treatment of full-thickness wounds. Cultured autologous keratinocytes were suspended in fibrin and grafted together with decellularised human dermis (Alloderm) in a porcine animal model, involving 10 animals over 4 weeks. Wound healing was evaluated by planimetry. Histology included morphological analysis as well as immunohistochemistry at regular intervals (1, 2 and 4 weeks). The results showed both successful histo-integration of the in vivo composite grafts and reduced wound contraction, compared with the control group (plain epithelial grafts). Histologically a neo-epithelium originated from the grafted cells on top of the decellularised dermis, as well as a reconstituted basement membrane. After 4 weeks cellular ingrowth into the dermal matrix could be observed. The successful combination of a keratinocyte-fibrin suspension and acellular dermis applied in a single step onto full-thickness wounds resulted in closure.     

Comparison of renal ablation with cryotherapy, dry radiofrequency, and saline augmented radiofrequency in a porcine model.

BACKGROUND: Needle ablative therapy has recently generated a lot of interest in the urologic community. We compare renal lesions produced in a porcine model using three forms of needle ablative energy: cryoablation (CR), dry radiofrequency (RF), and saline augmented radiofrequency (SARF). STUDY DESIGN: In 10 farm pigs, under ultrasonographic guidance, 40 laparoscopic renal lesions were produced: 825-mm CR lesions were produced with 2.4-mm cryoprobes (Endocare Inc, Irvine, CA), after 1-mL preinfusions of 14.6% saline, 12 SARF lesions were created with 22-gauge needles (2 mL/minute 14.6% saline, 50 W 510 kHz RF for 60 seconds), 12 RF lesions were created with a 2-cm array LeVeen electrode and an RF2000 generator using impedance limited 30 to 60 W double activations (Radiotherapeutics Corp, Mountain View, CA), and 8 RF lesions were produced using 22-gauge needles and double 10 W activations with the RF2000 generator. Eight animals were sacrificed after 1 week for acute pathology. An additional two animals were sacrificed at 8 weeks to provide chronic pathology results for the LeVeen dry RF and SARF modalities. RESULTS: CR produced a regular 18- to 22-mm zone of complete necrosis bordered by a 1.5- to 2.5-mm zone of partial necrosis. Acutely, LeVeen RF and single-needle RF produced lesions 25 to 45 mm and 6 to 10 mm wide, respectively. Acutely, SARF produced irregular cone-shaped lesions 15 to 31 mm wide. Only one of eight acute LeVeen RF lesions showed complete necrosis; none of the four 8-week LeVeen RF lesions displayed complete necrosis. Two of the four 8-week SARF lesions displayed complete necrosis. The remainder of the LeVeen RF, single-needle RF, and SARF lesions showed early, indeterminate tubular damage with relative glomerular sparing and bands of complete necrosis (0.5 to 1.5 mm) and inflammation (0.5 to 2 mm) at the periphery. Only CR could be consistently monitored with laparoscopic ultrasonography. CONCLUSIONS: Renal cryoablation produces well-defined, completely necrotic lesions that can be monitored reliably with ultrasonography. Longer followup may be required to characterize the full extent of renal necrosis produced by RF, but in the short run, none of the RF modalities reliably produced 100% necrosis in all cases.     

Gelatin matrix treatment of complex renal injuries in a porcine model

PURPOSE: We developed a complex porcine renal laceration model at our laboratory to test the efficacy of an abbreviated, sutureless treatment regimen using FloSeal gelatin matrix hemostatic sealant (Baxter Healthcare Corp., Fremont, California). We evaluated the influence of preliminary renal arterial occlusion on hemostatic efficacy and assessed the risk of delayed hematoma or urinoma formation after treatment. MATERIALS AND METHODS: A total of 21 commercial swine underwent celiotomy with creation of a complex upper pole renal injury using a 4 x 4 cm cruciate press instrument. The injury was uniformly produced at the caudal extent of the upper third portion of the left kidney. Subjects were prospectively randomized into 3 treatment groups. Experimental animals were treated with the application of gelatin matrix with (7 in group 1) or without (7 in group 2) preliminary renal arterial occlusion. Control subjects (7 in group 3) were treated with conventional horizontal mattress sutured gelatin sponge bolsters over the capsular injury. Operative blood loss, time to hemostasis and volume of gelatin matrix required for hemostasis were compared among the groups. Abdominal computerized tomography with intravenous contrast medium was performed in each animal 7 days postoperatively. RESULTS: Gelatin matrix use resulted in significantly less mean blood loss (80.7 and 99.0 ml in groups 1 and 2, respectively) vs conventional suture treatment (191.8 ml in group 3, p = 0.036). Time to hemostasis was similarly decreased (1.1, 2 to 2.5 and 5.8 minutes in groups 1 to 3, respectively, p = 0.009). Followup abdominal computerized tomography with contrast medium revealed no clinically significant perinephric fluid collections (greater than 2 cm). CONCLUSIONS: FloSeal gelatin matrix hemostatic sealant provided effective hemostasis after complex renal injury with and without preliminary vascular control. No delayed bleeding or clinically significant urinoma formation was noted. These findings suggest a possible increased role for FloSeal gelatin matrix in renal salvage surgery.     

A novel approach to closure of perineal wounds during abdominoperineal resection: use of fibrin sealant

Abdominoperineal resection is associated with significant morbidity. The perineal wound poses a unique risk and complications are common, including skin breakdown, abscess, sinus tracts, perineal herniation, and evisceration. A 2-component fibrin sealant made from pooled human plasma has been proven to achieve hemostasis and tissue sealing. We report a case series of 5 consecutive patients in whom we used this fibrin sealant during perineal wound closure. Of our patients, 2 patients (40%) were diabetic and 4 patients (80%) received preoperative radiotherapy. The median body mass index was 32 (calculated as weight in kilograms divided by height in meters squared). The patients were at increased risk of perineal wound dehiscence and infection. Median follow-up was 6 months, and no patients had perineal wound complications. A fibrin sealant could be used as an alternative to more invasive procedures, such as flap reconstruction, in patients at high risk of perineal wound dehiscence.     

腹部刀刺伤97例诊治分析

目的探讨腹部刀刺伤的诊断及治疗。方法回顾性分析我院2004年1月至2008年12月收治的97例腹部刀刺伤手术的临床资料。结果本组治愈96例。其中,手术92例,均为腹壁穿透伤,剖腹探查未见脏器损伤12例;非手术治疗4例,均为腹壁损伤。死亡1例。结论休克、大网膜及腹腔脏器外脱、腹痛伴腹膜炎体征、诊断性腹腔穿刺阳性均是手术指征。复合、复杂刀刺伤及时行CT检查有助于病情诊断。术中仔细探查腹腔脏器,避免漏诊、漏治,是腹部刀刺伤的诊治关键。     

Preliminary results of using a commercial fibrin sealant in the treatment of fistula-in-ano

A prospective non-randomised study fibrin sealant injection to manage patients with fistula-in-ano, with magnetic resonance imaging (MRI) monitoring, was performed during the period 5/6/1999 to 28/2/2000. The aim was to determine whether a fibrin sealant could be used as a treatment modality for anorectal fistula and the usefulness of MRI perineum to monitor the disease activity. Ten patients were included in the study. Mean age was 47 years (range 7 months to 70 years). Male: female ratio was 9:1. Mean follow-up duration was 26.4 weeks. The overall success rate was 60%. The success rate of different fistula types were different (60%, 0%, 100% for intersphincteric, transphincteric, subcutaneous, respectively). Variable decrease in signal on STIR images and contrast enhancement was noted in the patients with successful and failure of fibrin sealant injection. In conclusion, fibrin sealant injection is a useful alternative treatment in the management of fistula-in-ano. MRI is helpful in delineating the anatomy of fistula-in-ano but not a useful tool to follow-up disease activity.     

Fibrin sealant improves graft adherence in a porcine full-thickness burn wound model

IntroductionAutograft take and rapid wound closure is essential for the survival of severely burned patients. Loss of skin grafts typically occurs during the first few days after coverage, mainly due to shear forces and inadequate contact with the wound bed. Slow-clotting fibrin sealant, applied with a spray-on device, has been shown to improve healing of skin grafts in large wounds. However, its use in burn wounds has not been studied so far.Study aimTo evaluate the effectiveness of sprayed fibrin sealant in excised and grafted full-thickness burns.Material and methodsTen female Yorkshire pigs (30–45 kg) received a full-thickness contact burn of approximately 15% total body surface area. The burns were excised to the level of the muscular fascia after 24 h and covered with meshed skin autograft (mesh ratio 1:3). Wounds were randomized to either fibrin sealant (n = 20) or standard skin staples (n = 16) for graft fixation. Fibrin sealant was used as a slow-clotting spray (4 IU thrombin/ml). Outcome measurements included clinical scoring at days 2, 5, 9 and 14 postoperatively, planimetric analysis of wound closure, and histological examination of epidermal and dermal thickness 14 days after autografting.ResultsIn the fibrin sealant group, graft adherence scores were significantly increased (p < 0.02) and graft dislocation scores significantly decreased (p < 0.01) at days 2 and 5 postoperatively, when compared to controls. Planimetric analysis of remaining open mesh interstices showed acceleration of wound closure in the fibrin sealant group but did not reach statistical significance (day 14 p = 0.04 at significance level p < 0.025). Wound contraction, occurrence of hematoma, and dermal as well as epidermal thickness were not different between the groups at 14 days postoperatively.ConclusionThe results indicate that the use of slow-clotting fibrin sealant spray for autograft fixation is advantageous over skin staples. Easy handling and reduced graft dislocation at early time points are key qualities of this method.     

Treatment of experimental osteomyelitis with a fibrin sealant antibiotic implant

Two methods currently are available for the delivery of antibiotics: intravenous injection with a long-term indwelling catheter and local implant of antibiotic-containing polymethylmethacrylate beads. Both of these methods have significant disadvantages. A fibrin sealant implant, impregnated with tobramycin, was evaluated in a rabbit model of osteomyelitis to determine whether it has the potential of supplying a basis for bone reconstruction and providing an improved treatment method for the delivery of antibiotics to orthopaedic infections. Localized tibial osteomyelitis, with methicillin-sensitive Staphylococcus aureus, was developed surgically in female New Zealand White rabbits. After 2 weeks, rabbits with evidence of osteomyelitis were treated with debridement alone, debridement plus systemic tobramycin, debridement plus fibrin sealant, debridement plus fibrin sealant loaded with tobramycin, polymethylmethacrylate beads loaded with tobramycin, or not treated at all (control). After 4 weeks of therapy, the rabbits were sacrificed and the involved bones were cultured for concentrations of methicillin-sensitive Staphylococcus aureus per gram of bone and marrow. Preliminary data (N = 14) indicate fibrin sealant plus tobramycin may be as effective as polymethylmethacrylate beads plus tobramycin against methicillin-sensitive Staphylococcus aureus osteomyelitis in a rabbit model.     

改良纤维蛋白胶封堵治疗消化道瘘4例报告

目的 探讨改良纤维蛋白胶封堵治疗消化道瘘的临床应用价值.方法 应用纤维蛋白胶联合明胶海绵治疗3例术后肠外瘘和1例胰瘘患者,观察其临床疗效.结果 封堵1次成功者2例,2次者2例;4例均获得愈合;封堵开始至愈合平均时间(9.2±4.3)d,无并发症发生.结论 纤维蛋白胶联合明胶海绵治疗消化道瘘能有效地促进瘘愈合缩短病程.     

Multicenter trial to evaluate the safety and potential efficacy of pooled human fibrin sealant for the treatment of burn wounds

OBJECTIVE: The primary purpose of this multicenter study was to evaluate the safety and potential efficacy of a solvent/detergent-treated commercial fibrin sealant (human) for topical hemostasis in skin grafting. METHODS: The study involved a prospective evaluation of changes in viral titers in patients with burns less than 15% after treatment with fibrin sealant (human). Each patient served as his/her own control for an unblinded, randomized comparison of donor site hemostasis and healing. Preoperative serum was obtained to screen for viral titers. At autografting, the recipient site and one of two randomly chosen donor sites were treated with fibrin sealant (human). The use of other hemostatic agents, including epinephrine was prohibited. Each donor site was covered with gauze to collect blood for estimation of the relative amount of bleeding. The healing of the graft and donor sites was observed. Viral titers and wounds were checked monthly for 6 months, and at 9 and 12 months postoperatively. RESULTS: Viral titers for human immunodeficiency virus; hepatitis A, B, and C; Epstein-Barr virus; and cytomegalovirus were obtained before and after treatment. Of 47 patients, 34 completed the full year of observation. After treatment, there were no seroconversions to any of the aforementioned viruses. Bleeding at the recipient site appeared well controlled with fibrin sealant (human). Although investigators felt that fibrin sealant (human) improved donor site hemostasis, differences in hemoglobin measurements of blood-soaked dressings failed to reach significance. No differences were noted with regard to acceleration of donor site healing, graft take, or scar maturation at the two groups of donor sites. Anecdotally, the maturation of the recipient site appeared to be accelerated. CONCLUSION: Fibrin sealant (human) is safe for use during excision and grafting, and its topical hemostatic potential needs to be examined in patients with larger burns. Its role in scar maturation also needs to be investigated.     

Diagnostic laparoscopy in abdominal stab wounds: a prospective, randomized study

BACKGROUND: The optimal strategy for identifying patients with abdominal stab wounds requiring surgical repair has not been defined. The potential benefits of diagnostic laparoscopy by incorporating it into the routine diagnostic workup of patients with anterior abdominal stab wounds was evaluated in a two-layer, randomized study. METHODS: From May 1997 through January 2002, stable patients without peritonitis but with demonstrated peritoneal violation were randomized (A) to exploratory laparotomy (AEL) (n = 23) or diagnostic laparoscopy (ADL) (n = 20). Simultaneously, patients with equivocal peritoneal violation on local wound exploration were randomized (B) to diagnostic laparoscopy (BDL) (n = 28) or expectant nonoperative management (BNOM) (n = 31). Hospital morbidity, length of stay, and costs were primary endpoints, with postdischarge disability being a secondary endpoint. RESULTS: In patients with peritoneal penetration (AEL vs. ADL), there were minimal differences in the therapeutic operation rate (8 of 23 [AEL] vs. 8 of 20 [ADL], p = 0.761), mortality (none), morbidity (3 of 23 vs. 2 of 20, p = 0.999), hospital stay (mean +/- SD) (5.7 +/- 2.5 vs. 5.1 +/- 4.0 days, p = 0.049), hospital costs (4.6 +/- 1.3 vs. 4.8 +/- 1.9 x 1,000 EUR, p = 0.576), and length of sick leave (34 +/- 12 vs. 29 +/- 11 days, p = 0.305). In patients with equivocal peritoneal penetration (BDL vs. BNOM), laparoscopy found more mostly minor organ injuries (7 of 28 [BDL] vs. 1 of 31 [BNOM], p = 0.022) with no significant difference in therapeutic operations (3 of 28 vs. 1 of 31, p = 0.337) or morbidity (3 of 28 vs. 0 of 31, p = 0.101), but was associated with increased length of stay (2.6 +/- 2.1 vs. 1.9 +/- 1.8 days, p = 0.022), hospital costs (4.2 +/- 1.3 vs. 1.5 +/- 1.1 x 1,000 EUR, p = 0.000), and sick leave requirements (18 of 23 vs. 8 of 28 of eligible patients, p = 0.001). CONCLUSION: In patients with demonstrated peritoneal violation, laparoscopy offers little benefit over exploratory laparotomy. In patients with equivocal peritoneal penetration on local wound exploration, laparoscopy detects more mostly minor organ injuries than expectant nonoperative management but is associated with increased hospital stay, costs, and sick leave requirements. Overall, diagnostic laparoscopy cannot be recommended as a routine diagnostic tool in anterolateral abdominal and thoracoabdominal stab wounds.     

Penetrating abdominal stab wounds: a plea for a more conservative policy

This is a retrospective study of 107 penetrating abdominal stab wounds which have been reviewed on the basis of the clinical indications for surgery. Eighty-four patients underwent laparotomy. The unnecessary laparotomy rate was 35 per cent and the mortality 2.4 per cent. Important complications developed in 44 per cent of those undergoing surgery. Evaluation of clinical variables is presented and it is suggested that in the absence of shock, generalized peritonitis or evisceration, careful initial assessment, monitoring and regular re-examination would be a satisfactory method of treatment for many cases. This would result in a decrease in unnecessary laparotomies and associated excess morbidity.