In Vivo Analysis of the Morphologic Characteristics of Synthetic Mesh to Resist MRSA Adherence

Background

Synthetic mesh has significantly reduced recurrence rates for ventral hernia repair; however, prosthetic mesh infections remain a significant complication. We hypothesized that unique mesh constructs might alter the ability of various synthetic meshes to clear bacterial contamination. To evaluate this, we studied commercially available synthetic meshes ability to clear a bacterial contamination with methicillin resistant Staphylococcus aureus infection.

Methods

Two hundred and eighty-three rats underwent hernia repair with one of nine synthetic materials. Control animals were closed, and the remainder was inoculated with either 10⁴ or 10⁶ methicillin-resistant S. aureus (MRSA). Animals were survived for 30?days without systemic antibiotics. At necropsy, the mesh was harvested and quantitative cultures and bacterial clearance assessed.

Results

All clean repairs remained sterile. Rates of bacterial clearance for 10⁴ repairs revealed that unprotected monofilament materials cleared significantly more bacteria than composite meshes and multifilament meshes (p?=?<0.01 and p?=?0.01, respectively). At higher levels of bacterial contamination (10⁶), all materials had a reduction in bacterial clearance, although monofilament materials had higher bacterial clearance compared to composite meshes (p?=?0.03).

Conclusions

Monofilament unprotected polypropylene and polyester mesh can clear a large percentage of MRSA contaminants. Multifilament, composite anti-adhesive barrier meshes, and laminar antimicrobial impregnated mesh are not able to clear bacterial contamination with MRSA. Unique properties of synthetic material should be considered when evaluating a prosthetic for high-risk incisional hernia repair.     

Mycobacterium tuberculous peritonitis in CAPD patients: a report of 11 patients and review of literature

Background

The aims of the present report were to document our experience of the prevalence of tuberculous peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients, mode of presentation, diagnosis and outcome and to discuss the current published data about catheter removal.

Methods

A retrospective study of CAPD patients with tuberculous peritonitis was done. A minimum of three specimens of peritoneal fluid were examined for acid-fast bacilli smears. The BACTEC 9000 Blood Culture Series of instruments were used for the culture of Mycobacterium tuberculosis. After 2005, patients were treated with anti-tuberculous treatment, and catheter retention was started in our patients.

Results

There were eleven patients (2.6 %) with tuberculous peritonitis among 414 CAPD patients. M. tuberculosis accounted for 4.47 % of all peritonitis episodes. The incidence of tuberculous peritonitis was 1/794 months. There were eight males and three females. The mean age was 49 years. Intestinal obstruction was reported in two patients, and two patients were treated for antecedent peritonitis. One of them had a simultaneous fungal peritonitis. One patient each developed a peritoneo-cutaneous fistula and ultrafiltration failure. Three were successfully treated without the removal of catheter.

Conclusion

Based on the analysis of all published reports of tuberculous peritonitis, there was no significant difference in patient survival between patients in whom CAPD catheter was removed or retained. Tuberculous peritonitis should be considered in patients with neutrophilic ‘sterile’ peritonitis with no response to antibacterial medications, predominance of lymphocytic peritonitis and in bacterial peritonitis not responding to antibiotics. After an early diagnosis, with close monitoring, an effort to retain the catheter after 5 days of anti-tuberculous therapy may be attempted.     

Non-tuberculous mycobacterial PD peritonitis in Australia

Purpose

Peritonitis can be a severe complication of peritoneal dialysis (PD) due to associated morbidity and mortality. Non-tuberculous mycobacteria (NTM) are a rare cause of PD peritonitis, with high rates of catheter removal and conversion to haemodialysis, and a reported mortality as high as 40 %. The incidence, culprit NTM species, and outcomes associated with PD peritonitis have not been described in many countries, including Australia.

Methods

We examined the Australia and New Zealand Dialysis and Transplant Registry from 1 October 2003 to 31 December 2009 for all prevalent peritoneal dialysis patients. Patient characteristics, organisms, treatment and outcome for all NTM PD peritonitis episodes were obtained.

Results

Twelve cases of NTM PD peritonitis were reported, including the first reports of infection due to Mycobacterium hassiacum and Mycobacterium neoaurum. The incidence of NTM PD peritonitis was approximately 1 per 1000 PD patient-years. Recovery occurred in 11 patients, including 3 without removal of their Tenckhoff catheters. A range of antibiotics were utilised. One patient died of sclerosing peritonitis 5 months after diagnosis of PD peritonitis.

Conclusion

Non-tuberculous mycobacteria PD peritonitis is a rare cause of peritonitis, and mortality may be lower than previously reported. Catheter removal occurred in the majority of patients, and adverse outcomes were not observed for those in whom it was retained.     

Transgastric endoscopic peritoneoscopy does not lead to increased risk of infectious complications

Background

It remains important to determine the risk of bacterial contamination and infectious complications of the peritoneal cavity as it pertains to transgastric natural orifice translumenal endoscopic surgery (NOTES) procedures. The infectious implications of such procedures have been quantified in animal models. This report discusses the infectious risks of transgastric endoscopic peritoneoscopy (TEP) in a human clinical trial.

Methods

Under institutional review board approval, 40 patients scheduled for laparoscopic Roux-en-Y gastric bypass (LRYGB) participated in this study. The TEP procedure was performed without preoperative gastric decontamination and without laparoscopic guidance. Preoperative intravenous antibiotics were given. Saline aspirates were taken from the gastric lumen before endoscopic gastrotomy creation and from the peritoneal cavity after transgastric access. Samples were sent for culture, identification, and bacterial counts. Subgroup analysis was performed on patients taking proton pump inhibitors (PPIs). These data were compared with data for ??sterile?? peritoneal aspirates from a historical cohort of 50 patients undergoing LRYGB.

Results

The median number of bacteria isolated from the gastric aspirates was 980 colony-forming units (CFU)/ml (n?=?40). The median number of bacteria isolated from the peritoneal aspirates was 323?CFU/ml. Cross-contamination from the stomach to the peritoneal cavity was documented in eight cases. No abscesses or anastomotic leaks were recorded. One port-site infection occurred. Subgroup analysis of 15 patients receiving PPIs showed elevated bacterial counts in gastric aspirates and the post-TEP peritoneal samples compared with patients not receiving PPIs (n?=?25). This subgroup on PPI??s did not have an increase in infectious complications.

Conclusions

Contamination of the peritoneal cavity does occur with TEP, but this does not lead to an increased risk of infectious complications. Similarly, patients receiving PPIs have an increased gastric bacterial load and increased contamination after TEP but not an increased risk of infectious complications.     

Long-term effects of peritonitis on peritoneal dialysis outcomes

Purpose

Prevalence of peritoneal dialysis is low in part because of the perceived high risk for complications such as peritonitis. However, in the most recent era, peritonitis incidence and its effects on patient outcomes may have diminished. The aim of this study was to analyze peritonitis incidence and its impact on patient and technique survival, as well as on the kidney transplantation rate and outcome.

Methods

All peritoneal dialysis patients from a county hospital between year 2001 and 2011 were retrospectively included. Patients were divided into two groups with respect to peritonitis. The primary composite end-point consisted of a 3-year patient mortality or technique loss. Secondary end-points were patient survival and probability of kidney transplantation with respect to peritonitis history.

Results

Among 85 study patients, there were 61 peritonitis episodes. The incidence of peritonitis was 0.339 ± 0.71 episode per patient per 12 months or one episode per 29.3 ± 22.2 patient-months. The time to peritonitis was shorter, and peritonitis was more likely in patients on continuous ambulatory peritoneal dialysis than in automated peritoneal dialysis patients. Patient and technique survival and transplantation rate were similar in the group with and without peritonitis history. The primary end-point was recorded in 35 % of patients with peritonitis history and in 54 % of those without peritonitis (p = 0.04). In a multivariate analysis, the only variable significantly associated with the primary end-point and with patient survival was patient age at start of peritoneal dialysis.

Conclusions

In contemporary peritoneal dialysis patients, timely treated peritonitis may not be associated with adverse patient and technique outcomes. The transplantation rate is unaffected by the peritonitis history. Peritoneal dialysis may be promoted as the first dialysis method in appropriate patients.     

A 10-year retrospective cohort study on the risk factors for peritoneal dialysis-related peritonitis: a single-center study at Tokai University Hospital

Background

Common outcomes of peritoneal dialysis (PD)-related peritonitis include catheter removal and transition to hemodialysis (HD). According to recent data, the incidence of PD-related peritonitis in Japan is not low, and peritonitis is the most common cause of withdrawal from PD. Against this backdrop, the purpose of this study is to determine the incidence of PD-related peritonitis at the Outpatient Nephrology Clinic of Tokai University Hospital (hereafter “the Clinic”) and to examine causative bacteria and the risk factors related to the development of peritonitis.

Methods

We investigated all PD-related peritonitis episodes of 192 PD patients who visited the Clinic during the period from April 1, 2001 to March 31, 2011 and established the incidence of PD-related peritonitis, along with culture-negative peritonitis rates. Regarding the risk factors that are associated with the development of peritonitis, we examined patient backgrounds, whether an automated peritoneal dialysis (APD) device was used, and which type of connection system was employed.

Results

The incidence of peritonitis was one episode per 64.5 patient-months, and the culture-negative peritonitis rate was 16.4 %. Of the cultured bacterial isolates 71.3 % were Gram-positive cocci, including 25.0 % of coagulase-negative staphylococci, 13.2 % of methicillin-susceptible Staphylococcus aureus (MSSA), and 6.6 % of methicillin-resistant Staphylococcus aureus (MRSA). Gram-negative rods were 19.1 %. Risk factors associated with the development of peritonitis included age at the start of PD [odds ratio 1.042, 95 % confidence interval (CI) 1.016–1.069, p value = 0.001], diabetes mellitus nephropathy (DMN) (odds ratio 22.003, 95 % CI 2.101–230.452, p value = 0.010), and the use of a sterile tubing welder device (STWD) (odds ratio 2.399, 95 % CI 1.043–5.521, p value = 0.040).

Conclusions

Regarding the situation of peritonitis at a single center during the 10-year period of this study, risk factors associated with the development of peritonitis included age at the start of PD, DMN, and the use of an STWD.     

Optimal sutures for use in the abdomen: an evaluation based on the formation of adhesions and abscesses

Purpose

This study explored the optimal suture materials for use in the peritoneal cavity based on the formation of adhesions and abscesses under clean and contaminated conditions.

Methods

The parietal peritoneum and muscle layer of rats were incised. The incision was followed by interrupted suturing in the clean group. A suspension of E. coli (1.0 × 10⁶) plus Bacteroides fragilis (1.0 × 10⁵) was sprayed onto the incision in the contaminated group, followed by interrupted suturing. Four types of sutures were used: nonabsorbable multifilament silk, absorbable multifilament Polyglactin 910 (Vicryl^®), absorbable monofilament Polydioxanone (PDS^®), and Poliglecaprone 25 (Monocryl^®). The rats were killed at 2, 4 or 8 weeks after the surgery.

Results

The incidence of adhesions in the clean group was low with Polyglactin 910. The incidence of adhesions was 96 % or higher regardless of the suture type in the contaminated group. The incidence of severe adhesions was low with Polyglactin 910 and Poliglecaprone 25 and significantly higher with Polydioxanone in the contaminated group. The incidence of abscess formation around the silk was significantly higher than the other three types of sutures in the contaminated group.

Conclusion

Polyglactin 910 was less likely to form adhesions than the other three types of sutures under both conditions, suggesting that Polyglactin 910 may be the optimal type of suture to use in the peritoneal cavity.     

Novel technique of overlaying a poly-l-lactic acid nanosheet for adhesion prophylaxis and fixation of intraperitoneal onlay polypropylene mesh in a rabbit model

Background

One problem with polypropylene mesh (PPM) used to repair abdominal wall hernias is dense adhesions to the visceral surface. The authors developed the biocompatible poly-l-lactic acid (PLLA) nanosheet (thickness?Methods The PLLA nanosheet was fabricated by the spin-coating method and peeling technique with polyvinyl alcohol (PVA) as a supporting film. Two 1.5-cm-square pieces of mesh were implanted on each peritoneal side of the midline incision. The mesh was fixed to the peritoneum with a suture and then overlaid with a 4-cm-square piece of Seprafilm or nanosheet. To examine the fixative property, mesh was overlaid with Seprafilm or nanosheet without a fixed suture. After 4?weeks, mesh adhesion, inflammatory reaction, fixation, and dislocation of mesh were evaluated.

Results

Nanosheet-overlaid meshes were flexible and fit over the peritoneum. Adhesion was observed in 10% of the nanosheet-overlaid meshes and in 50% of the Seprafilm-overlaid meshes. The adhesion tenacity grade was significantly lower with the nanosheet-overlaid meshes (0.1?±?0.1) than with the Seprafilm-overlaid meshes (1.0?±?0.4) (p?=?0.029), and the percentage of the adhesion area also was lower with the nanosheet-overlaid meshes (1.0?±?1.0% vs 8.5?±?3.2%; p?=?0.037). The mean inflammatory cell counts were lower with the nanosheet-overlaid meshes (p?=?0.0023). Regarding the fixative property, 37.5% of the nanosheet-overlaid meshes were fixated on the peritoneum, but no Seprafilm-overlaid mesh was fixated.

Conclusion

Overlaying of a PLLA nanosheet was effective for adhesion prophylaxis of intraperitoneal mesh. It also may have a possible beneficial effect on fixation of mesh.     

Implantation of Prophylactic Nonabsorbable Intraperitoneal Mesh in Patients With Peritonitis Is Safe and Feasible

Background

Patients with peritonitis undergoing emergency laparotomy are at increased risk for postoperative open abdomen and incisional hernia. This study aimed to evaluate the outcome of prophylactic intraperitoneal mesh implantation compared with conventional abdominal wall closure in patients with peritonitis undergoing emergency laparotomy.

Method

A matched case-control study was performed. To analyze a high-risk population for incisional hernia formation, only patients with at least two of the following risk factors were included: male sex, body mass index (BMI) >25 kg/m², malignant tumor, or previous abdominal incision. In 63 patients with peritonitis, a prophylactic nonabsorbable mesh was implanted intraperitoneally between 2005 and 2010. These patients were compared with 70 patients with the same risk factors and peritonitis undergoing emergency laparotomy over a 1-year period (2008) who underwent conventional abdominal closure without mesh implantation.

Results

Demographic parameters, including sex, age, BMI, grade of intraabdominal infection, and operating time were comparable in the two groups. Incidence of surgical site infections (SSIs) was not different between groups (61.9 vs. 60.3 %; p = 0.603). Enterocutaneous fistula occurred in three patients in the mesh group (4.8 %) and in two patients in the control group (2.9 %; p = 0.667). The incidence of incisional hernia was significantly lower in the mesh group (2/63 patients) than in the control group (20/70 patients) (3.2 vs. 28.6 %; p < 0.001).

Conclusions

Prophylactic intraperitoneal mesh can be safely implanted in patients with peritonitis. It significantly reduces the incidence of incisional hernia. The incidences of SSI and enterocutaneous fistula formation were similar to those seen with conventional abdominal closure.     

Evaluation of bacterial contamination after “pure” (totally) transvaginal NOTES® diagnostic peritoneoscopy with biopsies in swine: a comparative study with laparoscopy

Introduction

Bacterial contamination from viscerotomy is a barrier to natural orifice translumenal endoscopic surgery (NOTES). The aim of this survival study is to evaluate pure (totally) transvaginal NOTES bacterial contamination compared with laparoscopy in pigs.

Methods

Twelve adult female pigs underwent peritoneoscopy with liver and peritoneal biopsies, using either laparoscopy (Glap, six animals) or pure transvaginal (GNOTES) access, and were maintained alive for 7 days. In all animals, blood cultures were taken at baseline, and after 24 h and 7 days postoperatively. Swab cultures from vagina (GNOTES) and skin (Glap) were obtained pre- and post-antisepsis. Peritoneal fluid culture was obtained at necropsy. For statistical analysis, Glap and GNOTES were compared for presence of positive bacterial cultures (qualitative bacterial analysis) using Fisher’s test, with level of significance set at p < 0.05.

Results

All animals had good postoperative outcome. One animal had transient perioperative bleeding from a transvaginal access. Two animals in Glap and one in GNOTES had positive blood cultures after the procedure. All animals from GNOTES and Glap presented with mixed flora pre-antisepsis. After antisepsis, one animal (GNOTES) presented with a positive vaginal swab culture (a single bacterial strain was identified). There was no positive skin swab culture in Glap. There were no signs of intra-abdominal infection at necropsy. In two animals, one from Glap and another from GNOTES, intra-abdominal culture was positive for Corynebacterium spp. and Escherichia coli, respectively. There was no correlation between the bacterial flora found at the access site and in the peritoneal cultures.

Conclusions

Pure transvaginal peritoneoscopy with liver and peritoneal biopsy in swine is feasible and associated with bacterial contamination comparable to laparoscopy. Peritoneal bacterial contamination was clinically insignificant after 1 week postoperatively. Preoperative antisepsis provided significant reduction of bacterial load prior to transvaginal and laparoscopic procedures.     

Does Presoaking Synthetic Mesh in Antibiotic Solution Reduce Mesh Infections? An Experimental Study

Background

Prosthetic mesh infection is one of the most challenging complications after hernia repair. We evaluate the efficacy of soaking mesh in antibiotics to prevent prosthetic infection in an animal model of clean–contaminated ventral hernia repair (VHR).

Material and Methods

Rats underwent an acute VHR with one of four synthetic meshes (composite multifilament polyester (Parietex PCO), multifilament polyester (Parietex TET), composite monofilament polypropylene (Ventralight), or monofilament polypropylene (SoftMesh)). Prior to implantation, mesh was soaked in saline or 10 mg/ml of vancomycin for 15 min. Following implantation, meshes were contaminated with 10⁴ CFU of methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Thirty days after implantation, mesh samples were cultured and evaluated under scanning electron microscope for biofilm formation.

Results

Presoaking meshes significantly improves bacterial clearance in composite meshes and multifilament polyester mesh. MRSA clearance was as follows for all meshes (saline-soaked vs. vanco-soaked): Parietex PCO (0 vs. 56 %, p?=?0.006), Parietex TET (0 vs. 50 %, p?=?0.01), Ventralight (20 vs. 78 %, p?=?0.012), and SoftMesh (70 vs. 80 %, p?=?0.6). MRSA biofilm formation was consistent with bacterial growth.

Conclusion

Presoaking multifilament and composite mesh in vancomycin solution reduces MRSA bacterial growth. Its implementation may reduce the risk of mesh infection in clean–contaminated cases, although further investigation with human trials should be performed.     

Trainee performance at robotic console and benchmark operative times

Introduction and hypothesis

It is an ongoing challenge to maintain surgical efficiency while integrating trainee participation. We hypothesize that a program of graduated surgical responsibility for trainees does not hinder operative efficiency.

Methods

This was a retrospective cohort study of trainee performance times, collected prospectively in real time, for robotic cases performed at one university hospital between September 2008 and August 2011. The primary aim was to compare overall operative times between cases performed by trainees versus attendings. Secondary aims were to compare operative times for major portions of each operation by level of training and to establish benchmark operative times for trainees.

Results

During the study period, 98 cases had recorded trainee performance times. Total robot docked time was longer for trainees than for attendings (155 vs 132 min, p?=?0.011), but mean performance times for hysterectomy (70 vs 59 min, p?=?0.096) and sacrocolpopexy (76 vs 79 min, p?=?0.545) were similar. Within the trainees, there was no correlation between surgical time and rank for each step of the procedures. Utilizing mean performance times for all trainees, benchmark operative times were established for each step of hysterectomy in minutes: right side (21), left side (21), bladder flap (10), colpotomy (15), and cuff closure (19); similarly, for sacrocolpopexy: sacral and peritoneal dissection (12), anterior cuff dissection (10), posterior cuff dissection (8), anterior mesh attachment (15), posterior mesh attachment (18), sacral mesh attachment (12), and peritoneal closure (9).

Conclusion

In a program of graduated surgical responsibility, robotic operative efficiency was comparable when trainees were involved as console surgeons.     

Prospective evaluation of peritoneal fluid contamination following transabdominal vs. transanal specimen extraction in laparoscopic left-sided colorectal resections

Background

Natural orifice specimen extraction (NOSE) in colorectal surgery prevents the need for an enlarged port site or minilaparotomy to extract the surgical specimen. The downside of this technique may be an increased risk of bacterial contamination of the peritoneal cavity from the external milieu. The aim of this study was to prospectively analyze the peritoneal bacterial contamination in NOSE and non-NOSE laparoscopic colorectal procedures.

Methods

Consecutive patients operated for sigmoid diverticulitis with laparoscopic approach and transanal extraction of the specimen from January to December 2010 at our university hospital were enrolled. Patients who underwent a laparoscopic sigmoidectomy in the same study period with conventional specimen extraction were used as reference. Peritoneal fluid samples were collected under sterile conditions at the end of the procedure and sent for gram stain as well as anaerobic, aerobic, and fungal cultures.

Results

Twenty-nine patients underwent laparoscopic sigmoidectomy for diverticulitis with transanal NOSE, while 9 patients underwent laparoscopic sigmoidectomy with conventional specimen extraction during the same period. The two groups were successfully matched 1:2 (17 NOSE and 9 non-NOSE) according age, sex, ASA, and Charlson comorbidity score. The contamination rate of peritoneal fluid was 100% vs. 88.9% in NOSE and non-NOSE procedures, respectively (P?=?0.23). Overall and major complications rates were 27.6% vs. 11.10% (P?=?0.41) and 5.08% vs. 11.1% (P?=?1) in NOSE vs. non-NOSE procedures, respectively. In the NOSE group there was a statistically significant lower consumption of oral paracetamol (P?=?0.007) and of oral tramadol (P?=?0.02).

Conclusions

Although a higher peritoneal contamination was found in the NOSE procedures, there were no significant differences in clinical outcomes relative to standard approach. Avoiding a minilaparotomy to extract the specimen resulted in a significantly lower postoperative analgesic requirement in the NOSE group.     

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.     

Montelukast: a novel therapeutic option in eosinophilic peritonitis

Background

Eosinophilic peritonitis is a recognised complication of peritoneal dialysis and has an incompletely understood pathophysiology. Current treatment options, including change of dialysate, change of peritoneal dialysis modality, steroids or antihistamines, are supported only by case reports with a lack of controlled trials or evidence-based guidelines. Leukotrienes are proinflammatory arachidonic acid metabolites produced by leucocytes and are involved in eosinophil chemotaxis. Montelukast is an orally administered leukotriene receptor antagonist commonly used in managing childhood atopic illnesses and theoretically safe for use in patients with renal failure.

Case diagnosis and treatment

We describe the first reported case of recurrent, symptomatic, eosinophilic peritonitis in a 15-year-old girl successfully treated with leukotriene receptor antagonist montelukast after changes in dialysate and treatment with antihistamines failed to adequately control eosinophilic peritoneal infiltrates or symptoms.

Conclusions

Current scientific understanding of leukotrienes and eosinophil migration suggest that montelukast may be a well-tolerated, safe and efficacious treatment for eosinophilic peritonitis complicating peritoneal dialysis. Further cases and comparative studies are required to develop an evidence base for treatment of this condition.     

The inflammatory response in transgastric surgery: gastric content leak leads to localized inflammatory response and higher adhesive disease

Background

Risk of gastric spillage during transgastric surgery is a potential complication of NOTES procedures. The aim of this study was to determine risk outcomes from gastric spillage in a rat survival model by measuring local and systemic inflammatory markers, adhesive disease, and morbidity.

Methods

We performed a minilaparotomy with needle aspiration of 2 ml of gastric contents mixed with 2 ml of sterile saline (study group, SG) or 4 ml of sterile saline (control group, CG) injected into the peritoneal cavity of 60 male rats. Inflammatory markers (TNFα, IL-6, and IL-10) were analyzed at 1, 3, 6, and 24 h postoperatively by obtaining plasma levels and peritoneal washings. At necropsy, the peritoneal cavity was examined grossly for adhesions.

Results

Adhesions were seen more frequently in the SG versus the CG (100% vs. 33.3%, p < 0.014). There was a significant difference in the peritoneal TNFα levels in the SG compared with the CG, which peaked 1 h after surgery (p < 0.02). Both peritoneal IL-6 and IL-10 levels were higher in the SG versus the CG, which peaked 3 h after surgery (p < 0.005 and p < 0.001, respectively). All peritoneal inflammatory markers returned to undetectable levels at 24 h for both groups. Plasma cytokines were undetectable at all time intervals.

Conclusion

The inflammatory response was found to be a localized and not systemic event, with plasma cytokine levels remaining normal while peritoneal washings revealed a brisk, short-lived localized inflammatory response. There was a significantly higher rate of adhesive disease in the SG compared with the CG; this, however did not translate into a difference in apparent clinical outcome. We conclude that gastric leakage in this NOTES rodent model induces a localized inflammatory response, followed by mild to moderate adhesive disease. This may be important in human NOTES.     

Pure transvaginal umbilical hernia repair

Background

Transvaginal natural orifice transluminal endoscopic surgery (NOTES) procedures are at the forefront of minimally invasive innovation, remarkable for shorter recovery times and decreased postoperative pain [1, 2]. Most transvaginal procedures are performed as hybrid procedures [3]. To our knowledge, this is the first video depiction of a pure transvaginal umbilical hernia repair in a human.

Methods

This is a 38-year-old woman, body mass index 36.4 kg/m², with a symptomatic port site hernia in the umbilical region after a previous laparoscopic cholecystectomy. The patient was positioned in stirrups in a steep Trendelenburg position. Sterilization of vaginal cavity was performed with 10 % povidone–iodine solution. A 2 cm transverse incision at the posterior fornix was made, and a SILS port (Covidien, North Haven, CT) was introduced. One 12 mm trocar and two 5 mm trocars were placed through SILS port. Standard straight laparoscopic instruments were used. A 12 cm round Parietex mesh (Covidien) was placed in a specimen retrieval bag and deployed into the peritoneal cavity. The mesh was extracted, unfolded in the abdominal cavity, and circumferentially fixated to the abdominal wall with an AbsorbaTack device (Covidien). The colpotomy incision was closed with a running absorbable suture.

Results

The procedure lasted 103 min and was performed on an outpatient basis. No intraoperative complications occurred. The patient was doing well and had no pain or recurrence at 2, 6, and 9 months’ follow-up.

Conclusions

Our initial experience with transvaginal ventral hernia repair in humans suggests that this procedure is feasible and safe. This approach may improve cosmesis and decrease the risk of future ventral hernias. Potential cons may include a longer operative time, mesh infection, and risk of visceral injury with a pure transvaginal approach. As transvaginal surgery evolves, techniques and devices will become increasingly refined to tackle these challenges.     

An experimental study exploring the relationship between the size of bacterial inoculum and bacterial adherence to prosthetic mesh

Background

Infection is a major concern with medical implants. Surgical meshes used for the repair of abdominal wall hernias are associated with wound infection rates ranging from 7 to 18 %. Although mesh infection is relatively rare, once a patient shows clinical signs of mesh infection, the surgeon may be required to remove the mesh, resulting in additional surgery, morbidity, and cost. The usual causative organisms associated with cases of mesh infection are Staphylococcus species. The first stage of implant infection is bacterial adherence to the biomaterial. An accurate assessment of adherent bacteria to medical prosthetics is therefore important in order to determine the infection risk associated with surgical implants.

Methods

This experimental study evaluated the relationship between the size of the bacterial inoculum and bacterial adherence to three commonly used hernia prosthetics (polypropylene, polyester, and ePTFE). Tenfold dilutions of S. epidermidis (Evans-ATCC 12228) and S. aureus (Rosenbach-ATCC 25923), created with phosphate-buffered saline, were used to inoculate each of the meshes in 3 ml of tryptone soya broth for 18 h at 37 °C, 95 % air/5 % CO₂. The number of viable bacteria in each dilution was calculated using a spot plate technique. The number of adherent bacteria to the meshes was counted using direct imaging analysis with scanning electron microscopy and expressed as a mean.

Results

One hundred eight mesh samples were analysed. The size of the bacterial inoculum of S. epidermidis significantly influenced the number of adherent bacteria to the mesh, and lower rates of adhesion were observed with smaller inoculums for all three meshes (polypropylene, p = 0.02; ePTFE p = 0.03; polyester p = 0.02). A similar, albeit less profound, pattern of results was observed with S. aureus. Bacterial adherence was observed with inoculum sizes as small as <10 bacteria.

Conclusions

The results demonstrate that even a very low number of bacterial inoculums can result in adherence to hernia biomaterials and that the level of adherence is directly related to the size of the inoculum. These in vitro results provide evidence that the size of the inoculum is important in the colonization of hernia biomaterials and demonstrate the importance of minimising the bacterial inoculum in the clinical setting.     

Outcomes of peritoneal dialysis catheter reinsertion: does the cause of initial removal matter?

Purpose

In this study, we aimed to compare patient and technique survival between the patients, in whom peritoneal dialysis (PD) catheter was removed due to severe peritonitis and then it was reinserted, and those, in whom PD catheter was removed due to non-peritonitis causes and then it was reinserted.

Method

Sixty-two patients, in whom PD catheter was reinserted surgically, were retrospectively analyzed in this cohort study. Group 1 consisted of 27 patients in whom PD catheter was removed due to severe peritonitis, whereas Group 2 consisted of 35 patients in whom PD catheter was removed due to non-peritonitis causes.

Results

There was no significant difference between Group 1 and Group 2 in terms of the estimation of overall patient survival [43 months (95 % CI 43.6–83.7) versus 80 months (95 % CI 52.8–107.3, p 0.362]. Similarly, there was no significant difference between Group 1 and Group 2 in terms of the estimation of overall technique survival [82 months (95 % CI 0–166.0) versus 31 months (95 % CI 9.7–52.3), p 0.346].

Conclusion

Our results suggest that there was no significant effect of causes of PD catheter removal (peritonitis vs. non-peritonitis) on the outcomes of PD treatment.