BMC Surgery - Latest articles

A historically controlled, single-arm, multi-centre, prospective trial to evaluate the safety and efficacy of MonoMax(R) suture material for abdominal wall closure after primary midline laparotomy. ISSAAC-Trial [NCT005725079]

2008-07-21

Background: Several randomized controlled trials have compared different suture materials and techniques for abdominal wall closure with respect to the incidence of incisional hernias after midline laparotomy and shown that it remains, irrespective of the methods used, considerably high, ranging from 9% to 20%. The development of improved suture materials which would reduce postoperative complications may help to lower its frequency.DesignThis is a historically controlled, single-arm, multi-centre, prospective trial to evaluate the safety of MonoMax(R) suture material for abdominal wall closure in 150 patients with primary elective midline incisions. INSECT patients who underwent abdominal closure using Monoplus(R) and PDS(R) will serve as historical control group. The incidences of wound infections and of burst abdomen are defined as composite primary endpoints. Secondary endpoints are the frequency of incisional hernias within one year after operation and safety. To ensure adequate comparability in surgical performance and recruitment, the 4 largest centres of the INSECT-Trial will participate. After hospital discharge, the investigators will examine the enrolled patients again at 30 days and at 12 1 months after surgery. Conclusion: This historically controlled, single-arm, multi-centre, prospective ISSAAC trial aims to assess whether the use of an ultra-long-lasting absorbable monofilament suture material is safe and efficient. Trial registration: NCT005725079

The Anal Fistula Plug versus the mucosal advancement flap for the treatment of Anorectal Fistula (PLUG trial)

2008-06-23

Background: Low transsphincteric fistulas less than 1/3 of the sphincter complex are easy to treat by fistulotomy with a high success rate. High transsphincteric fistulas remain a surgical challenge. Various surgical procedures are available, but recurrence rates of these techniques are disappointingly high. The mucosal flap advancement is considered the gold standard for the treatment of high perianal fistula of cryptoglandular origin by most colorectal surgeons. In the literature a recurrence rate between 0 and 63% is reported for the mucosal flap advancement. Recently Armstrong and colleagues reported on a new biologic anal fistula plug, a bioabsorbable xenograft made of lyophilized porcine intestinal submucosa. Their prospective series of 15 patients with high perianal fistula treated with the anal fistula plug showed promising results.The anal fistula plug trial is designed to compare the anal fistula plug with the mucosal flap advancement in the treatment of high perianal fistula in terms of success rate, continence, postoperative pain, and quality of life.Methods/designThe PLUG trial is a randomized controlled multicenter trial. Sixty patients with high perianal fistulas of cryptoglandular origin will be randomized to either the fistula plug or the mucosal advancement flap. Study parameters will be anorectal fistula closure-rate, continence, post-operative pain, and quality of life. Patients will be followed-up at two weeks, four weeks, and 16 weeks. At the final follow-up closure rate is determined by clinical examination by a surgeon blinded for the intervention.DiscussionBefore broadly implementing the anal fistula plug results of randomized trials using the plug should be awaited. This randomized controlled trial comparing the anal fistula plug and the mucosal advancement flap should provide evidence regarding the effectiveness of the anal fistula plug in the treatment of high perianal fistulas.Trial registrationISRCTN: 97376902

Intravenous postoperative fluid prescriptions for children: A survey of practice

Polly Davies, Tim Hall, Tariq Ali and Kokila Lakhoo — 2008-06-09

Background: Postoperative deaths and neurological injury have resulted from hyponatraemia associated with the use of hypotonic saline solutions following surgery. We aimed to determine the rates and types of intravenous fluids being prescribed postoperatively for children in the UK. Methods: A questionnaire was sent to members of the British Association of Paediatric Surgeons (BAPS) and Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI) based at UK paediatric centres. Respondents were asked to prescribe postoperative fluids for scenarios involving children of different ages. The study period was between May 2006 and November 2006. Results: The most frequently used solution was sodium chloride 0.45% with glucose 5% although one quarter of respondents still used sodium chloride 0.18% with glucose 4%. Isotonic fluids were used by 41% of anaesthetists and 9.8% of surgeons for the older child, but fewer for infants. Standard maintenance rates or greater were prescribed by over 80% of respondents. Conclusion: Most doctors said they would prescribe hypotonic fluids at volumes equal to or greater than traditional maintenance rates at the time of the survey. A survey to describe practice since publication of National Patient Safety Agency (NPSA) recommendations is required.

The efficacy of 'Radio guided Occult Lesion Localization' (ROLL) versus 'Wire-guided Localization' (WGL) in breast conserving surgery for non-palpable breast cancer: A randomized clinical trial – ROLL study

2008-05-21

Background: With the increasing number of non palpable breast carcinomas, the need of a good and reliable localization method increases. Currently the wire guided localization (WGL) is the standard of care in most countries. Radio guided occult lesion localization (ROLL) is a new technique that may improve the oncological outcome, cost effectiveness, patient comfort and cosmetic outcome. However, the studies published hitherto are of poor quality providing less than convincing evidence to change the current standard of care.The aim of this study is to compare the ROLL technique with the standard of care (WGL) regarding the percentage of tumour free margins, cost effectiveness, patient comfort and cosmetic outcome.Methods/designThe ROLL trial is a multi center randomized clinical trial. Over a period of 2–3 years 316 patients will be randomized between the ROLL and the WGL technique. With this number, the expected 15% difference in tumour free margins can be detected with a power of 80%. Other endpoints include cosmetic outcome, cost effectiveness, patient (dis)comfort, degree of difficulty of the procedures and the success rate of the sentinel node procedure.The rationale, study design and planned analyses are described.Trial Registration(http://www.clinicaltrials.gov, study protocol number NCT00539474)

Non-invasive monitoring of tissue oxygenation during laparoscopic donor nephrectomy

2008-04-17

Background: Standard methods for assessment of organ viability during surgery are typically limited to visual cues and tactile feedback in open surgery. However, during laparoscopic surgery, these processes are impaired. This is of particular relevance during laparoscopic renal donation, where the condition of the kidney must be optimized despite considerable manipulation. However, there is no in vivo methodology to monitor renal parenchymal oxygenation during laparoscopic surgery. Methods: We have developed a method for the real time, in vivo, whole organ assessment of tissue oxygenation during laparoscopic nephrectomy to convey meaningful biological data to the surgeon during laparoscopic surgery. We apply the 3-CCD (charge coupled device) camera to monitor qualitatively renal parenchymal oxygenation with potential real-time video capability. Results: We have validated this methodology in a porcine model across a range of hypoxic conditions, and have then applied the method during clinical laparoscopic donor nephrectomies during clinically relevant pneumoperitoneum. 3-CCD image enhancement produces mean region of interest (ROI) intensity values that can be directly correlated with blood oxygen saturation measurements (R2 > 0.96). The calculated mean ROI intensity values obtained at the beginning of the laparoscopic nephrectomy do not differ significantly from mean ROI intensity values calculated immediately before kidney removal (p > 0.05). Conclusion: Here, using the 3-CCD camera, we qualitatively monitor tissue oxygenation. This means of assessing intraoperative tissue oxygenation may be a useful method to avoid unintended ischemic injury during laparoscopic surgery. Preliminary results indicate that no significant changes in renal oxygenation occur as a result of pneumoperitoneum.

Different tissue reaction of oesophagus and diaphragm after mesh hiatoplasty. Results of an animal study

2008-04-12

Background: Laparoscopic mesh-reinforcement of the hiatal region in the treatment of gastroesophageal reflux disease (GERD) and paraesophageal hernia (PEH) reduces the risk of recurrence. However, there are still controversies about the technique of mesh placement, shape, structure and material. We therefore compared tissue integration and scar formation after implantation of two different polypropylene-meshes in a rabbit model. Methods: A total of 20 female chinchilla rabbits were included in this study. Two different meshes (Polypropylene PP, Polyglecaprone 25 Composite PP-PG) were implanted on the abdominal diaphragm around the oesophagus. After 3 months the implanted meshes were excised en-bloc. Histological and morphological analyses were carried out accordingly proliferation rate, apoptosis and collagen type I/III ratio. Results: Regarding proliferation rate of oesophagus PP (9.31 ± 3.4%) and PP-PG (13.26 ± 2.54%) differ in a significant (p = 0.0097) way. In the diaphragm we found a significant (p = 0.00066) difference between PP (9.43 ± 1.45%) and PP-PG (18.73 ± 5.92%) respectively. Comparing oesophagus and diaphragm we could prove a significant difference within PP-PG-group (p = 0.0195). Within PP-group the difference reached no statistical significance (p = 0.88). We found analogous results regarding apoptosis.Furthermore, there is a significant (p = 0.00013) difference of collagen type I/III ratio in PP-PG (12.28 ± 0.8) compared to PP (8.44 ± 1,63) in case of oesophageal tissue. Concerning diaphragm we found a significant difference (p = 0.000099) between PP-PG (8.85 ± 0.81) and PP (6.32 ± 1.07) as well. Conclusion: The histologic and morphologic characteristics after prosthetic enforcement of the hiatus in this animal model show a more distinct tissue integration using PP-PG compared to PP. Additionally, different wound healing and remodelling capability influence tissue integration of the mesh in diaphragm and oesophagus.

Influence of two different resection techniques (conventional liver resection versus anterior approach) of liver metastases from colorectal cancer on hematogenous tumor cell dissemination – prospective randomized multicenter trial

2008-03-05

Background: Surgical hepatic resection remains the treatment of choice for patients with liver metastases from colorectal cancer despite the use of alternative therapeutic strategies. Although this procedure provides long-term survival in a significant number of patients, 50–75% of the patients develop intra- and/or extrahepatic recurrence. One possible reason for tumor recurrence may be intraoperative hematogenous tumor cell dissemination due to mechanical manipulation of the tumor during hepatic resection. Surgical technique may have an influence on hematogenous tumor cell spread. We hypothesize that hematogenous tumor cell dissemination may be reduced by using the anterior approach technique compared to conventional liver resection.Methods/DesignThis is a multi-centre prospective randomized controlled, superiority trial to compare two liver resection techniques of liver metastases from colorectal cancer. 150 patients will be included and randomized intraoperatively after surgical exploration just prior to resection. The primary objective is to compare the anterior approach with the conventional liver resection technique with regard to intraoperative haematogenous tumor cell dissemination. As secondary objectives we examine five year survival rates (OS and DFS), blood loss, duration of operation, requirement of blood transfusions, morbidity rate, prognostic relevance of tumor cell detection in blood and bone marrow and the comparison of tumor cell detection by different detection methods. Conclusion: This trial will answer the question whether there is an advantage for the anterior approach technique compared to the conventional resection group with regard to tumor cell dissemination. It will also add further information about prognostic differences, safety, advantages and disadvantages of each technique.Trial registrationCurrent controlled trials – ISRCTN45066244

Enhanced susceptibility to infections in a diabetic wound healing model

2008-02-29

Background: Wound infection is a common complication in diabetic patients. The progressive spread of infections and development of drug-resistant strains underline the need for further insights into bacterial behavior in the host in order to develop new therapeutic strategies. The aim of our study was to develop a large animal model suitable for monitoring the development and effect of bacterial infections in diabetic wounds. Methods: Fourteen excisional wounds were created on the dorsum of diabetic and non-diabetic Yorkshire pigs and sealed with polyurethane chambers. Wounds were either inoculated with 2 × 108 Colony-Forming Units (CFU) of Staphylococcus aureus or injected with 0.9% sterile saline. Blood glucose was monitored daily, and wound fluid was collected for bacterial quantification and measurement of glucose concentration. Tissue biopsies for microbiological and histological analysis were performed at days 4, 8, and 12. Wounds were assessed for reepithelialization and wound contraction. Results: Diabetic wounds showed a sustained significant infection (>105 CFU/g tissue) compared to non-diabetic wounds (p < 0.05) over the whole time course of the experiment. S. aureus-inoculated diabetic wounds showed tissue infection with up to 8 × 107 CFU/g wound tissue. Non-diabetic wounds showed high bacterial counts at day 4 followed by a decrease and no apparent infection at day 12. Epidermal healing in S. aureus-inoculated diabetic wounds showed a significant delay compared with non-inoculated diabetic wounds (59% versus 84%; p < 0.05) and were highly significant compared with healing in non-diabetic wounds (97%; p < 0.001). Conclusion: Diabetic wounds developed significantly more sustained infection than non-diabetic wounds. S. aureus inoculation leads to invasive infection and significant wound healing delay and promotes invasive co-infection with endogenous bacteria. This novel wound healing model provides the opportunity to closely assess infections during diabetic wound healing and to monitor the effect of therapeutical agents in vivo.

The Quality Initiative in Rectal Cancer (QIRC) trial: study protocol of a cluster randomized controlled trial in surgery

2008-02-15

Background: Two unfortunate outcomes for patients treated surgically for rectal cancer are placement of a permanent colostomy and local tumor recurrence. Total mesorectal excision is a new technique for rectal cancer surgery that can lead to improved patient outcomes. We describe a cluster randomized controlled trial that is testing if the above patient outcomes can be improved through a knowledge translation strategy called the Quality Initiative in Rectal Cancer (QIRC) strategy. The strategy is designed to optimize the use of total mesorectal excision techniques.Methods and DesignHospitals were randomized to the QIRC strategy (experimental group) versus normal practice environment (control group). Participating hospitals, and the respective surgeon group operating in them, are from Ontario, Canada and have an annual procedure volume for major rectal cancer resections of 15 or greater. Patients were eligible if they underwent major rectal surgery for a diagnosis of primary rectal cancer. The surgeon-directed QIRC interventions included a workshop, use of opinion leaders, operative demonstrations, a post-operative questionnaire, and, audit and feedback. For an operative demonstration participating surgeons invited a study team surgeon to assist them with a case of rectal cancer surgery. The intent was to demonstrate total mesorectal excision techniques. Control arm surgeons received no intervention. Sample size calculations were two-sided, considered the clustering of data at the hospital level, and were driven by requirements for the outcome local recurrence. To detect an improvement in local recurrence from 20% to 8% with confidence we required 16 hospitals and 672 patients – 8 hospitals and 336 patients in each arm. Outcomes data are collected via chart review for at least 30 months after surgery. Analyses will use an intention-to-treat principle and will consider the clustering of data. Data collection will be complete by the end of 2007.DiscussionLower rates of permanent colostomy and local tumour recurrence in the intervention arm would suggest the QIRC strategy is efficacious. The strategy may act as a template for efforts to improve surgical quality in other areas and will contribute to knowledge on influencing surgeon practice.Trial registrationCurrent Controlled Trials ISRCTN78363167

Analysis of blood transfusion predictors in patients undergoing elective oesophagectomy for cancer

Abraham A Ayantunde, Ming Y Ng, Saurov Pal, Neil T Welch and Simon L Parsons — 2008-01-25

Background: Oesophagectomy for cancers is a major operation with significant blood loss and usage. Concerns exist about the side effects of blood transfusion, cost and availability of donated blood. We are not aware of any previous study that has evaluated predictive factors for perioperative blood transfusion in patients undergoing elective oesophagectomy for cancer.This study aimed to audit the pattern of blood crossmatch and to evaluate factors predictive of transfusion requirements in oesophagectomy patients. Methods: Data was collected from the database of all patients who underwent oesophagectomy for cancer over a 2-year period. Clinico-pathological data collected included patients demographics, clinical factors, tumour histopathological data, preoperative and discharge haemoglobin levels, total blood loss, number of units of blood crossmatched pre-, intra- and postoperatively, number of blood units transfused, crossmatched units reused for another patient and number of blood units wasted.Clinico-pathological variables were evaluated and logistic regression analysis was performed to determine which factors were predictive of blood transfusion. Results: A total of 145 patients with a male to female ratio of 2.5:1 and median age of 68 (40–85) years were audited. The mean preoperative haemoglobin (Hb) was 13.0 g/dl. 37% of males (Hb < 13.0 g/dl) and 29% of females (Hb < 11.5 g/dl) were anaemic preoperatively. A total of 1241 blood units were crossmatched and 316 units were transfused to 71 patients. Seventy four patients (51%) did not require blood transfusion during their hospital episode. 846 blood units not used for oesophagectomy patients were reused for other patients and 79 units were wasted. The overall crossmatch to transfusion ratio was 4:1 and reuse and wastage rates were 65.2% and 6.3% respectively. The independent predictors of blood transfusion include age >70 years, Hb level <11.0 g/dl, T-stage, presence of postoperative complications and anastomotic leak. Conclusion: The cohort of patients audited was over-crossmatched. The identified independent predictors of blood transfusion should be considered in preoperative blood ordering for oesophagectomy patients. This study has directly led to a reduction in the maximum surgical blood-ordering schedule for oesophagectomy to 2 units and a reaudit is underway.