Dimitri Dorcaratto

Irreversible electroporation of the liver: is there a safe limit to the ablation volume?

Irreversible electroporation is a fast-growing liver ablation technique. Although safety has been well documented in small ablations, our aim is to assess its safety and feasibility when a large portion of liver is ablated. Eighty-seven mice were subjected to high voltage pulses directly delivered across parallel plate electrodes comprising around 40% of mouse liver. One group consisted in 55 athymic-nude, in which a tumor from the KM12C cell line was grown and the other thirty-two C57-Bl6 non-tumoral mice. Both groups were subsequently divided into subsets according to the delivered field strength (1000 V/cm, 2000 V/cm) and whether or not they received anti-hyperkalemia therapy. Early mortality (less than 24 hours post-IRE) in the 2000 V/cm group was observed and revealed considerably higher mean potassium levels. In contrast, the animals subjected to a 2000 V/cm field treated with the anti-hyperkalemia therapy had higher survival rates (OR = 0.1, 95%CI = 0.02–0.32, p < 0.001). Early mortality also depended on the electric field magnitude of the IRE protocol, as mice given 1000 V/cm survived longer than those given 2000 V/cm (OR = 4.7, 95%CI = 1.8–11.8, p = 0.001). Our findings suggest that ionic disturbances, mainly due to potassium alterations, should be warned and envisioned when large volume ablations are performed by IRE.

Laparoscopic Distal Pancreatectomy: Feasibility Study of Radiofrequency-Assisted Transection in a Porcine Model

BACKGROUND AND AIM Despite technological improvements in pancreatic surgery, the incidence and morbidity of pancreatic leak after resection of distal pancreas are persistently high in most series. Laparoscopic distal pancreatectomy (LDP) is today the gold standard procedure for benign and certain malignant neoplasms of the pancreatic body and tail in specialized centers. This study evaluated safety and feasibility of a radiofrequency (RF)-assisted transection device in a porcine model of LDP. MATERIALS AND METHODS LDP was performed on 10 pigs (median weight, 39.6 kg) using a new device based on an internally cooled RF-assisted electrode (Coolinside(®), Apeiron Medical, Valencia, Spain). The animals were subjected to daily observation and then sacrificed and necropsied at 4 weeks postoperatively. Primary end points were the development of postoperative pancreatic fistula using the Pancreatic Anastomotic Leak Study Group definition and/or the presence of abdominal amylase-rich fluid collections or abscesses during necropsy and pathological study and/or dye extravasation from the pancreatic remnant duct. Secondary end points were intra- or postoperative complications, surgery, and transection duration. RESULTS No clinically relevant postoperative pancreatic fistulas were observed. In one case a grade A postoperative fistula was diagnosed due to amylase drain concentration of more than 6200 IU/mL on postoperative day 4. Median peritoneal liquid amylase concentration on postoperative day 4 was 2399.0 IU/L (range, 819.2-7122.0 IU/L), similar to the median plasma amylase level of 1520.8 IU/L (range, 1015.3-4056.6 IU/L). Median surgery time was 93.5 minutes (range, 46.0-140.0 minutes), and median transection time was 4.5 minutes (range, 2.0-26.0 minutes). There was one postoperative wound infection. There were no postoperative deaths or major complications. During the histopathological study, the surgical margin of the remaining pancreas showed a common pattern with a central area of necrosis surrounded by granulomatous infiltrate and fibrosis. Ductal obliteration was observed. No purulent inflammatory infiltrate or abscesses were present. CONCLUSION Experimental findings suggest that performing pancreatic transection with Coolinside in a animal model of LDP is feasible and safe.

Current indications, surgical technique and results of anterior sphincter repair as a treatment of faecal incontinence

Abstract Faecal incontinence is a high prevalence disease in the general population. This pathology is commonly under-estimated and causes a great impact on clinical status and on the quality of life of affected patients. The prevalence of faecal incontinence in several studies has been estimated between 2% and 15% of the general population. The prevalence increases if we study selected populations, such as elderly people. The main cause of faecal incontinence is obstetric anal sphincter damage. In the past years, the presence of incontinence due to sphincter lesions, especially the obstetric ones, was an absolute indication of anterior anal sphincter repair. Actually, after knowing the long term follow up results of this technique, as well as the evolving knowledge on faecal incontinence and the development of new diagnostic and therapeutic techniques, this technique might be selected for cases with large sphincter defects. However there is limited information in the current literature on indications, surgical technique and results of anterior sphincter repair. The aim of this review is to analyse scientific evidence on current indications, surgical technique features and results of anterior sphincter repair as a therapy for faecal incontinence, also giving our point of view on controversial issues. A bibliography search was undertaken using Medline database including articles published from January 1985 to January 2009.

Resultados del abordaje laparoscópico en el tratamiento de la obstrucción aguda del intestino delgado por adherencias y hernias internas

INTRODUCTION Laparotomy is the standard approach for the surgical treatment of acute small bowel obstruction (ASBO). PATIENTS AND METHODS From February 2007 to May 2012 we prospectively recorded all patients operated by laparoscopy in our hospital because of ASBO due to adhesions (27 cases) and/or internal hernia (6 cases). A preoperative abdominal CT was performed in all cases. Patients suffering from peritonitis and/or sepsis were excluded from the laparoscopic approach. It was decided to convert to laparotomy if intestinal resection was required. RESULTS The mean age of the 33 patients who underwent surgery was 61.1 ± 17.6 years. 64% had previous history of abdominal surgery. 72% of the cases were operated by surgeons highly skilled in laparoscopy. Conversion rate was 21%. Operative time and postoperative length of stay were 83 ± 44 min. and 7.8 ± 11.2 days, respectively. Operative time (72 ± 30 vs 123 ± 63 min.), tolerance to oral intake (1.8 ± 0.9 vs 5.7 ± 3.3 days) and length of postoperative stay (4.7 ± 2.5 vs 19.4 ± 21 days) were significantly lower in the laparoscopy group compared with the conversion group, although converted patients had greater clinical severity (2 bowel resections). There were two severe complications (Clavien-Dindo III and V) in the conversion group. CONCLUSIONS In selected cases of ASBO caused by adhesions and internal hernias and when performed by surgeons highly skilled in laparoscopy, a laparoscopic approach has a high probability of success (low conversion rate, short hospital length of stay and low morbidity); its use would be fully justified in these cases.

Calidad de vida en pacientes con cáncer de esófago y de estómago

The study of the health related quality of life in patients with digestive tract cancer, and particularly in those with tumours of the oesophagus and stomach, provides useful information for selecting the most suitable therapeutic option. It may also be used to predict the impact of the disease and its possible treatments on the physical, emotional and social condition of the patient. Various sensitive and reliable tools have been developed over the past decades that are capable of measuring the quality of life of patients; the use of questionnaires has made it easier to exchange information between the patient and the doctor. The pre- and post-operative variations in the quality of life in patients with oesophageal-gastric cancer are of prognostic value on the outcome of the disease. For all these reasons, the health related quality of life is currently considered, along with disease free survival and absence of recurrences, one of the most important parameters in order to assess the impact on the patients of a particular oncological treatment. The aim of this article is to review the role of the health related quality of life assessment, as well as the various tools which are available to measure it in patients with oesophageal-gastric cancer.

Impact of monopolar radiofrequency coagulation on intraoperative blood loss during liver resection: a prospective randomised controlled trial

Abstract Purpose: To evaluate the impact of using monopolar thermal coagulation based on radiofrequency (RF) currents on intraoperative blood loss during liver resection. Materials and methods: A prospective randomised controlled trial was planned. Patients undergoing hepatectomy were randomised into two groups. In the control group (n = 10), hemostasis was obtained with a combination of stitches, vessel-sealing bipolar RF systems, sutures or clips. In the monopolar radiofrequency coagulation (MRFC) group (n = 18), hemostasis was mainly obtained using an internally cooled monopolar RF electrode. Results: No differences in demographic or clinical characteristics were found between groups. Mean blood loss during liver resection in the control group was more than twice that of the MRFC group (556 ± 471 ml vs. 225 ± 313 ml, p = .02). The adjusted mean bleeding/transection area was also significantly higher in the control group (7.0 ± 3.3 ml/cm2 vs. 2.8 ± 4.0 ml/cm2, p = .006). No significant differences were observed in the rate of complications between the groups. Conclusions: The findings suggest that the monopolar electrocoagulation created with an internally cooled RF electrode considerably reduces intraoperative blood loss during liver resection.

Radiofrequency pancreatic ablation and section of the main pancreatic duct does not lead to necrotizing pancreatitis.

Objective The aim of this study was to determine whether radiofrequency ablation (RFA) of the pancreas and subsequent transection of the main pancreatic duct may avoid the risk of both necrotizing pancreatitis and postoperative pancreatic fistula (POPF) formation. Methods Thirty-two rats were subjected to RFA and section of the pancreas over their portal vein. Animals were killed at 3, 7, 15, and 21 days (groups 0–3, respectively). Two additional control groups (sham operation and user manipulation only, respectively) of 15 days of postoperative period were considered. Postoperative complications, histological changes (including morphometric and immunohistochemical analysis), and incidence of POPF were evaluated. Results A significant increase in serum amylase levels (P < 0.05) on the third postoperative day, which return to baseline levels in the following weeks, was noted in groups 0 to 3. Those groups showed a rapid atrophy of the distal pancreas by apoptosis with no signs of necrotizing pancreatitis or POPF. The distal pancreas in groups 1 to 3 compared with group 0 and control groups showed a significant increase of small islets (<1000 µm2). Conclusions The rapid acinar atrophy of the distal pancreas after RFA and section of the pancreatic ducts in this model does not lead to necrotizing pancreatitis.

Minimally invasive techniques in the treatment of severe acute pancreatitis

Open necrosectomy, the standard surgical treatment of infected pancreatic necrosis (IPN), presents a high rate of postoperative complications and an associated mortality of 20–60%. In the last decade various minimally invasive approaches (MIA) have been proposed for the treatment of IPN and the results seem to improve on those reported with open necrosectomy. These MIA include: percutaneous, retroperitoneal, endoscopic (endoluminal) and laparoscopic (transperitoneal). The adoption of the step-up approach in the management of severe acute pancreatitis (SAP) facilitates the implementation of MIA as the surgical treatment of choice in most cases. Since MIA require the expertise of radiologists, endoscopists and surgeons, patients suffering SAP should be treated by multidisciplinary teams in referral centers. We describe the MIA currently available and discuss their advantages, disadvantages, and results.

Indicacion actual, técnica quirúrgica y resultados de la reparación anterior esfinteriana en el tratamiento de la incontinencia fecal

Faecal incontinence is a high prevalence disease in the general population. This pathology is commonly under-estimated and causes a great impact on clinical status and on the quality of life of affected patients. The prevalence of faecal incontinence in several studies has been estimated between 2% and 15% of the general population. The prevalence increases if we study selected populations, such as elderly people. The main cause of faecal incontinence is obstetric anal sphincter damage. In the past years, the presence of incontinence due to sphincter lesions, especially the obstetric ones, was an absolute indication of anterior anal sphincter repair. Actually, after knowing the long term follow up results of this technique, as well as the evolving knowledge on faecal incontinence and the development of new diagnostic and therapeutic techniques, this technique might be selected for cases with large sphincter defects. However there is limited information in the current literature on indications, surgical technique and results of anterior sphincter repair. The aim of this review is to analyse scientific evidence on current indications, surgical technique features and results of anterior sphincter repair as a therapy for faecal incontinence, also giving our point of view on controversial issues. A bibliography search was undertaken using Medline database including articles published from January 1985 to January 2009.

Long-term effectiveness of irreversible electroporation in a murine model of colorectal liver metastasis

Irreversible electroporation (IRE) has recently gained in popularity as an ablative technique, however little is known about its oncological long-term outcomes. To determine the long-time survival of animals treated with a high dose of IRE and which histological changes it induces in tumoral tissue, IRE ablation was performed in forty-six athymic-nude mice with KM12C tumors implanted in the liver by applying electric current with different voltages (2000 V/cm, 1000 V/cm). The tumors were allowed to continue to grow until the animals reached the end-point criteria. Histology was harvested and the extent of tumor necrosis was semi-quantitatively assessed. IRE treatment with the 2000 V/cm protocol significantly prolonged median mouse survival from 74.3 ± 6.9 days in the sham group to 112.5 ± 15.2 days in the 2000 V/cm group. No differences were observed between the mean survival of the 1000 V/cm and the sham group (83.2 ± 16.4 days, p = 0.62). Histology revealed 63.05% ± 23.12 of tumor necrosis in animals of the 2000 V/cm group as compared to 17.50% ± 2.50 in the 1000 V/cm group and 25.6% ± 22.1 in the Sham group (p = 0.001). IRE prolonged the survival of animals treated with the highest electric field (2000 V/cm). The animals in this group showed significantly higher rate of tumoral necrosis.