Gut ischemia, oxidative stress, and bacterial translocation in elevated abdominal pressure in rats

The purpose of this experimental study was to investigate whether the increased intraabdominal pressure due to gas insufflation creates intestinal ischemia leading to oxygen free radical production and bacterial translocation. A group of 88 rats were studied, 40 of which were subjected to a 15 mmHg pressure pneumoperitoneum for 60 minutes, with the following parameters being studied: mean arterial pressure after carotid catheterization; intestinal microcirculation by means of the laser-Doppler technique; gut metabolic activity (O2 extraction) by blood sampling from portal vein and carotid artery; intestinal, hepatic, splenic, and lung free radical production (malondialdehyde); and bacterial translocation toward the mesenteric lymph nodes, liver, and spleen at 3 and 18 hours after pneumoperitoneum deflation. The mean arterial pressure exhibited no alterations, whereas the jejunal mucosa microcirculation was significantly decreased (p = 0.0001), as was the gut metabolic activity (p = 0.025). Malondialdehyde was increased in gut mucosa (p = 0.0002), liver (p = 0.02), spleen (p = 0.03), and lung (p = 0.017). Bacterial translocation toward the mesenteric lymph nodes (p = 0.002), spleen (p = 0.002), and liver (p = 0.05) was increased in the 3-hour group; in the 18-hour group bacteria were not found in mesenteric lymph nodes but were in liver (p = 0.008) and spleen (p = 0.035). It is concluded that elevated intraabdominal pressure in the rat leads to intestinal ischemia, oxygen free radical production, and bacterial translocation. These results must be reproduced in humans and their clinical significance clarified.

Benefits of a synbiotic formula (Synbiotic 2000Forte) in critically Ill trauma patients: early results of a randomized controlled trial

BACKGROUND

Since probiotics are considered to exert beneficial health effects by enhancing the host's immune response, we investigated the benefits of a synbiotics treatment on the rate of infections, systemic inflammatory response syndrome (SIRS), severe sepsis, and mortality in critically ill, mechanically ventilated, multiple trauma patients. Length of stay in the intensive care unit (ICU) and number of days under mechanical ventilation were also evaluated.

METHOD

Sixty-five patients were randomized to receive once daily for 15 days a synbiotic formula (Synbiotic 2000Forte, Medipharm, Sweden) or maltodextrin as placebo. The synbiotic preparation consisted of a combination of four probiotics (10(11) CFU each): Pediococcus pentosaceus 5-33:3, Leuconostoc mesenteroides 32-77:1, L. paracasei ssp. paracasei 19; and L. plantarum 2,362; and inulin, oat bran, pectin, and resistant starch as prebiotics. Infections, septic complications, mortality, days under ventilatory support, and days of stay in ICU were recorded.

RESULTS

Synbiotic-treated patients exhibited a significantly reduced rate of infections (P = 0.01), SIRS, severe sepsis (P = 0.02), and mortality. Days of stay in the ICU (P = 0.01) and days under mechanical ventilation were also significantly reduced in relation to placebo (P = 0.001).

CONCLUSION

The administration of this synbiotic formula in critically ill, mechanically ventilated, multiple trauma patients seems to exert beneficial effects in respect to infection and sepsis rates and to improve the patient's response, thus reducing the duration of ventilatory support and intensive care treatment.

500 intragastric balloons: what happens 5 years thereafter?

BACKGROUND

The BioEnterics Intragastric Balloon (BIB) has been considered an effective, less invasive method for weight loss, as it provides a permanent sensation of satiety. However, various non-randomized studies suggest BIB is a temporary anti-obesity treatment, which induces only a short-term weight loss. The purpose of this study was to present data of 500 obese who, after BIB-induced weight reduction, were followed up for up to 5 years.

METHODS

The BioEnterics BIB was used, and remained for 6 months. At 6, 12, and 24 months post-removal (and yearly thereafter), all subjects were contacted for follow-up.

RESULTS

From 500 patients enrolled, 26 were excluded (treatment protocol interruption); 474 thus remained, having initial body weight of 126.16 ± 28.32 kg, BMI of 43.73 ± 8.39 kg/m2, and excess weight (EW) of 61.35 ± 25.41. At time of removal, 79 (17%) were excluded as having percent excessive weight loss (EWL) of <20%; the remaining 395 had weight loss of 23.91 ± 9.08 kg (18.73%), BMI reduction of 8.34 ± 3.14 kg/m2 (18.82%), and percent EWL of 42.34 ± 19.07. At 6 and 12 months, 387 (98%) and 352 (89%) presented with weight loss of 24.14 ± 8.93 and 16.31 ± 7.41 kg, BMI reduction of 8.41 ± 3.10 and 5.67 ± 2.55 kg/m2, and percent EWL of 42.73 ± 18.87 and 27.71 ± 13.40, respectively. At 12 and 24 months, 187 (53%) and 96 (27%) of 352 continued to have percent EWL of >20. Finally, 195 of 474 who completed the 60-month follow-up presented weight loss of 7.26 ± 5.41 kg, BMI reduction of 2.53 ± 1.85 kg/m2, and percent EWL of 12.97 ± 8.54. At this time, 46 (23%) retained the percent EWL at >20. In general, those who lost 80% of the total weight lost during the first 3 months of treatment succeeded in maintaining a percent EWL of >20 long term after BIB removal: more precisely, this cutoff point was achieved in 83% at the time of removal and in 53%, 27%, and 23% at 12-, 24-, and 60-month follow-up.

CONCLUSION

BIB seems to be effective for significant weight loss and maintenance for a long period thereafter, under the absolute prerequisite of patient compliance and behavior change from the very early stages of treatment.

Splanchnic ischemia during laparoscopic cholecystectomy

BACKGROUND

Experimental studies have shown that elevation of intraabdominal pressure by means of gas insufflation produces hemodynamic disturbances in the peritoneal viscera, leading to splanchnic ischemia. The purpose of this clinical investigation is to reproduce the experimental data in humans undergoing laparoscopic cholecystectomy.

METHODS

Sixteen females participated in this study. Eight of them (the control group) were subjected to open laparotomy for biliary surgery, while on the remaining eight laparoscopic cholecystectomy was performed. In all patients hepatic microcirculation was registered during the time of operation using the laser-Doppler technique. A single-fiber laser-Doppler microprobe was introduced transcutaneously within the hepatic parenchyma, through a Chiba needle, under direct or laparoscopic vision. Additionally, gastric intramucosal/intramural pH, a low level of which indicates tissue ischemia, was assessed by means of a tonometric nasogastric catheter. Hepatic microcirculation and gastric intramucosal/intramural pH were assessed between controls and pneumoperitoneum-subjected patients, and within the laparoscopic surgery group, i.e., during pneumoperitoneum and after abdominal deflation.

RESULTS

Hepatic microcirculation was found to be significantly decreased in laparoscopic surgery patients in relation to controls (22.21 +/- 5.48 vs 57.52 +/- 18.06 perfusion units of flow, P = 0.0001) as was gastric intramural pH (7.15 +/- 0.16 vs 7.37 +/- 0.02, P = 0.003). Similarly, immediately after abdominal deflation, hepatic microcirculation exhibited a sudden elevation (22.21 +/- 5.48 vs 67.49 +/- 7.93 perfusion units of flow, P = 0.0001), while gastric intramural pH return to its normal values (7.15 +/- 0.16 vs 7.43 +/- 0.07, P = 0.0001).

CONCLUSIONS

It is concluded that during laparoscopic cholecystectomy abdominal organs are hypoperfused, leading to a splanchnic ischemia environment. The clinical significance of these events remains to be clarified.

Risk assessment in sepsis: a new prognostication rule by APACHE II score and serum soluble urokinase plasminogen activator receptor

INTRODUCTION

Early risk assessment is the mainstay of management of patients with sepsis. APACHE II is the gold standard prognostic stratification system. A prediction rule that aimed to improve prognostication by APACHE II with the application of serum suPAR (soluble urokinase plasminogen activator receptor) is developed.

METHODS

A prospective study cohort enrolled 1914 patients with sepsis including 62.2% with sepsis and 37.8% with severe sepsis/septic shock. Serum suPAR was measured in samples drawn after diagnosis by an enzyme-immunoabsorbent assay; in 367 patients sequential measurements were performed. After ROC analysis and multivariate logistic regression analysis a prediction rule for risk was developed. The rule was validated in a double-blind fashion by an independent confirmation cohort of 196 sepsis patients, predominantly severe sepsis/septic shock patients, from Sweden.

RESULTS

Serum suPAR remained stable within survivors and non-survivors for 10 days. Regression analysis showed that APACHE II ≥ 17 and suPAR ≥ 12 ng/ml were independently associated with unfavorable outcome. Four strata of risk were identified: i) APACHE II <17 and suPAR <12 ng/ml with mortality 5.5%; ii) APACHE II < 17 and suPAR ≥ 12 ng/ml with mortality 17.4%; iii) APACHE II ≥ 17 and suPAR <12 ng/ml with mortality 37.4%; and iv) APACHE II ≥ 17 and suPAR ≥ 12 ng/ml with mortality 51.7%. This prediction rule was confirmed by the Swedish cohort.

CONCLUSIONS

A novel prediction rule with four levels of risk in sepsis based on APACHE II score and serum suPAR is proposed. Prognostication by this rule is confirmed by an independent cohort.

Endoscopic management of gastrocutaneous fistula after bariatric surgery by using a fibrin sealant

BACKGROUND

Gastrocutaneous fistula is an uncommon and difficult to treat complication that occurs in 0.5% to 3.9% of patients who undergo gastric surgery. Sepsis usually follows, and, when it is not managed effectively, the associated mortality rate can be as high as 85%. A fibrin sealant was used to endoscopically manage gastrocutaneous fistulas that developed in 3 morbidly obese patients after bariatric surgery.

METHODS

Two of 14 (14.29%) patients who underwent vertical gastroplasty (MacLean procedure) developed a non-healing gastrocutaneous fistula. In addition, one of 24 (4.17%) patients who had a biliopancreatic diversion with preservation of pylorus developed a gastrocutaneous fistula. Endoscopic application of a fibrin sealant was performed under direct vision via a double-lumen catheter passed through a forward-viewing endoscope.

OBSERVATIONS

Treatment was successful in all patients after one or more endoscopic sessions in which the fibrin sealant was applied; no evidence of fistula was found at follow-up endoscopy.

CONCLUSIONS

Endoscopic closure of gastrocutaneous fistula with human fibrin tissue sealant is simple, safe, and effective, and, in some cases, can be life-saving. Endoscopic application of fibrin sealant should be considered a therapeutic option for treatment of gastrocutaneous fistula that develops after bariatric surgery.

Pro- and synbiotics to control inflammation and infection in patients with multiple injuries

BACKGROUND

A recent randomized clinical trial of our group disclosed considerable reduction of the infective sequelae after administration of a synbiotic formula, namely Synbiotic 2000FORTE, in patients with multiple injuries, the latter being a preparation of four probiotics. The mechanism of action of synbiotics was studied.

METHODS

A total of 72 patients with severe multiple injuries were allocated to a 15-day administration of either placebo or the synbiotic formula. The association of bloodstream infections, ventilator-associated pneumonia (VAP), serum levels of C-reactive protein (CRP), and endotoxins (LPS) were studied.

RESULTS

Sepsis in the field of bacteremia occurred in 13 patients treated with placebo (36.1%) compared with 5 patients treated with Synbiotic 2000FORTE (13.9%, p = 0.028 between groups). The time to progression to primary bacteremia was longer among patients treated with Synbiotic 2000FORTE compared with placebo (p = 0.0237 between groups). Twelve (33.3%) and five (13.9%) placebo-treated and probiotic-treated patients, respectively, developed ventilator-associated pneumonia with Acinetobacter baumannii as a bacterial cause (p = 0.047 between groups). Treatment with synbiotics was accompanied by reduction of white blood cell counts and LPS and CRP levels in either patients who did or did not develop sepsis.

CONCLUSIONS

Synbiotics contained in the studied formula decrease significantly the risk for sepsis by bloodstream infections and the occurrence of VAP by A. baumannii. The mechanisms of action might involve direct immunomodulatory effect, prevention of bacterial translocation, or most likely a combination of both.

Influence of enteral nutrition-induced splanchnic hyperemia on the septic origin of splanchnic ischemia

The purpose of this experimental study was to investigate whether enteral nutrition-induced postprandial intestinal hyperemia has a beneficial effect on the splanchnic ischemia due to sepsis. Fourteen dogs, after exposure to Escherichia coli endotoxin via portal vein administration were grouped according to whether they were fed enterally via a jejunostomy or given a placebo. Systemic hemodynamics; portal vein, hepatic, and superior mesenteric artery blood flow; hepatic and intestinal microcirculation; hepatic tissue PO2; intestinal pHi; and hepatic energy charge were assessed before, during, and after endotoxin infusion as well as during and after enteral or placebo feeding. All splanchnic hemodynamic parameters revealed a statistically significant decline (p = 0.001) during the endotoxin shock period relative to the baseline. After enteral feeding all parameters exhibited a statistically significant increase (p = 0.001) relative to the placebo group. The results of this study led us to suggest that enteral nutrition reverses the lipopolysaccharide infusion-induced splanchnic ischemia.

Endoscopic fibrin sealing of gastrocutaneous fistulas after sleeve gastrectomy and biliopancreatic diversion with duodenal switch

BACKGROUND AND AIM

Gastrocutaneous fistulas (GCF) are uncommon complications accounting for 0.5-3.9% of gastric operations. When their management is not effective, the mortality rate is high. This study reports the conservative treatment of GCF in morbidly obese patients who underwent biliopancreatic diversion with duodenal switch.

METHODS

Ninety-six morbidly obese patients were treated in our department with biliopancreatic diversion with duodenal switch (Marceau technique) and, in six of them, a high-output GCF developed. A general protocol was applied to all patients presenting a GCF. Everyone was treated by total parenteral nutrition (TPN) and somatostatin for at least 7 days after the appearance of the leak. If the leak continued, then fibrin glue was used as a tissue adhesive. Endoscopic application of the sealant was accomplished under direct vision via a double-lumen catheter passed through a forward-viewing gastroscope.

RESULTS

All patients were treated successfully with conservative treatment (either solely with TPN and somatostatin, or with endoscopic fibrin sealing sessions). No evidence of fistula was observed at gastroscopy 3 and 24 months after therapy.

CONCLUSION

The conservative treatment of GCF following biliopancreatic diversion with duodenal switch is highly effective. All patients should enter a protocol that includes TPN and somatostatin. When the GCF persist, endoscopic sealing glue should be considered before operation because it is simple, safe, effective and, in some cases, life-saving. Therefore, conservative treatment should be employed as a therapeutic option in GCF developing after bariatric surgery.

Hemodynamic events in the peritoneal environment during pneumoperitoneum in dogs

The purpose of this experimental study was to determine the hemodynamic conditions of intraperitoneal viscera during pneumoperitoneum by using either CO2 gas or helium (He) for insufflation. In 16 mongrel dogs (divided into a CO2 group and an He group) subjected to 14 mmHg pneumoperitoneum for 60 min, the following parameters were assessed at times before and 1, 2, 5, 15, 30, 45, and 60 min thereafter: (1) intestinal mucosal blood flow, by means of a laser-Doppler probe inplanted into a jejunal loop; (2) portal pressure and portal blood pCO2, through a catheter inserted via a mesenteric jejunal vein; (3) intramural jejunal pH (pHi), by means of a Tonometer, which expresses the degree of tissue ischemia; (4) inferior vena cava pressure and blood pCO2, through a catheter inserted via a femoral vein; and (5) from the systemic circulation pulse rate, arterial blood pressure, CO, CVP, PVP, SaO2, pCO2, and paO2 were measured through a catheter placed into a femoral artery and a Swan-Ganz thermodilution catheter inserted via external jugular vein: CI and SVR were then calculated. Jejunal mucosal blood flow was found decreased (P < 0.0001) and pHi revealed gut mucosal ischemia. Portal and inferior vena cava pressures were found to be elevated (P < 0.0001), as was blood pCO2 of these vessels (P < 0.001), in only the CO2 group. From the systemic circulation, arterial blood pressure, CO, CI, SaO2, and paO2 revealed a decrease (P < 0.001) while arterial pCO2 (only CO2 group), CVP, SVR, and PVP revealed an increase (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

A Four-Probiotics Regimen Combined with A Standard Helicobacter pylori-Eradication Treatment Reduces Side Effects and Increases Eradication Rates

Aim: To establish whether the addition of probiotics to a globally accepted Helicobacter pylori (H. pylori)-eradication scheme may reduce the rates of side effects and increase the eradication rates. Methods. Prospective, randomized, placebo-controlled trial of patients receiving eradication therapy for H. pylori in the eight participating centers. All patients received a 10-day proton pump inhibitor containing non-bismuth quadruple therapeutic regimen for H. pylori eradication (omeprazole 20 mg, amoxycillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg all twice daily orally) and were randomized to receive either probiotics (group A) or placebo (group B). The probiotic used combined four probiotic strains, i.e., Lactobacillus Acidophilus, Lactiplantibacillus plantarum, Bifidobacterium lactis, and Saccharomyces boulardii. Results. Data were analyzed for 329 patients in group A and 335 patients in group B. Fifty six (17.0%) patients in group A and 170 (50.7%) patients in group B reported the occurrence of an H. pylori treatment-associated new symptom or the aggravation of a pre-existing symptom of any severity (p < 0.00001). H. pylori was successfully eradicated in 303 patients in group A (92.0%) and 291 patients in group B (86.8%), (p = 0.028). Conclusion: Adding probiotics to the 10-day concomitant non-bismuth quadruple H. pylori eradication regimen increases the eradication rate and decreases side effects.

Tissue sealants in endoscopic applications for anastomotic leakage during a 25-year period

BACKGROUND

Anastomotic leakage after gastrointestinal operation is a complication difficult to manage because conservative therapy and/or reoperation may be unsuccessful and carry the risk of increased morbidity and mortality. The endoscopic use of tissue sealants appears to be a promising alternative to avoid operation.

METHOD

We present conclusively our 25-year experience with tissue sealing in a series of 63 patients referred after gastrointestinal anastomosis leakage; 48 of the upper and 15 of the lower gastrointestinal tract, experiencing a drainage volume ranging 50-2,400 mL.

RESULTS

Tissue glue was applied orally in 37, anally in 10, through the fistula tract in 8, and through a combination of approximation routes in another 8 cases. Biological glue (fibrin) was used in 47, cyanoacrylate in 8, and both glue types in another 8 patients. The total volume of fibrin applied was 2-36 mL, in a median of four sessions, 0.5-4 mL for cyanoacrylate, in a median of two sessions, and, whenever a combination of glues was used, a volume of 12-40 mL of fibrin plus 1-4 mL of cyanoacrylate, in a median of nine sessions. The median hospital stay after initiation of gluing was 14 days (range 8-32). The clinical and technical success rate was 96.8% (61 of 63 patients).

CONCLUSION

Tissue glue appears to be a valuable clinical tool that would prevent further operative interventions and the associated morbidity and mortality after a gastrointestinal anastomosis dehiscence. However, it must be borne in mind that repeated sessions and large volumes of sealants are necessary in many cases.

Probiotics for infectious diseases: more drugs, less dietary supplementation

According to current definitions, probiotics are live microorganisms that, when ingested in adequate quantities, exert a health benefit to the host. The action of probiotics in the host is exerted by three mechanisms: modulation of the content of gut microbiota; maintenance of the integrity of the gut barrier and prevention of bacterial translocation; and modulation of the local immune response by the gut-associated immune system. Regarding their role for the prevention and treatment of infectious diseases, adequate evidence coming from randomised clinical trials (RCTs) is available for antibiotic-associated diarrhoea (AAD), Clostridium difficile infection (CDI), acute gastroenteritis and infectious complications following admission to the Intensive Care Unit (ICU). Existing evidence supports their role for decreasing the incidence of AAD and CDI when administered in parallel with antimicrobials. They also shorten the duration of symptoms when administered in paediatric populations with acute gastroenteritis, particularly of rotavirus aetiology. Available evidence is not sufficient to support administration for the management of CDI. Regarding populations of critically ill patients, data from many RCTs suggest a decrease of infectious complications by starting feeding with probiotics following ICU admission, with the exception of patients suffering from severe pancreatitis. However, it should be underscored that all analysed RCTs are characterised by marked heterogeneity regarding the type of administered probiotic species, precluding robust recommendations.

Procalcitonin as an early indicator of outcome in sepsis: a prospective observational study

This study explores the role of procalcitonin (PCT) in predicting the outcome of sepsis. In a prospective multicentre observational investigation, blood was sampled within 24 h of onset of sepsis in 1156 hospitalised patients; 234 were in the intensive care unit (ICU) at the point of presentation of sepsis while 922 were not. PCT was estimated in serum by the ultrasensitive Kryptor assay in a double-blinded fashion. Among patients outside the ICU, mortality was 8% in those with PCT ≤0.12 ng/mL but 19.9% in those with PCT >0.12 ng/mL [P<0.0001, odds ratio (OR) for death: 2.606; 95% confidence interval (CI): 1.553-4.371]. Among patients whose sepsis presented in ICU, mortality was 25.6% in those with PCT ≤0.85 ng/mL but 45.3% in those with PCT >0.85 ng/mL (P=0.002; OR for death: 2.404; 95% CI: 1.385-4.171). It is concluded that PCT cut-off concentrations can contribute to predicting the outcome of sepsis and might be of particular value in identifying patients who would benefit from ICU admission.

Endoscopic fibrin sealing of high-output non-healing gastrocutaneous fistulas after vertical gastroplasty in morbidly obese patients

BACKGROUND

Fibrin glue was used in a various fields of surgery during the last 15 years, but its use has not been reported in bariatric surgery yet.

METHODS

In 2 out of 215 morbidly obese patients who underwent vertical banded gastroplasty, a non-healing gastrocutaneus fistula (GCF) developed. In both patients sepsis occurred, caused by a leak of the posterior gastric wall, which was managed by means of an unsuccessful reoperation. After that, sepsis recurred, and a non-healing GCF developed. These GCF were managed endoscopically by the use of a fibrin sealant (Beriplast P 2 ml set, Behring) as a tissue adhesive.

RESULTS

One injection was needed for the first case and six for the second in achieving full healing of the fistulas. No evidence of fistula was observed at gastroscopy 3 and 24 months after the end of therapy.

CONCLUSIONS

Endoscopic use of human fibrin sealant is simple, safe, effective and in some cases life-saving. This is a therapeutic option in high output GCF in morbidly obese patients.

Kinetics of angiopoietin-2 in serum of multi-trauma patients: correlation with patient severity

BACKGROUND

Angiopoietin-2 (Ang-2) is considered a proinflammatory mediator promoting vascular leakage. Its participation in the inflammatory process following multiple injuries was investigated.

METHODS

Blood was sampled on consecutive days from 54 patients with multiple injuries and six healthy volunteers. Ang-2 was estimated in serum by an enzyme immunoassay.

RESULTS

From the enrolled patients, 10 did not develop any complication; 17 developed systemic inflammatory response syndrome (SIRS); 16 developed sepsis and 11 severe sepsis. Among those who did not develop any complication, all survived. Ang-2 was increased on days 4 and 7 of follow-up in patients with SIRS. Ang-2 was highly increased upon advent of sepsis and of severe sepsis. Patients with serum levels below 15,200 pg/ml survived longer compared to those with levels above 15,200 pg/ml (p=0.015). OR for death with serum Ang-2 above 15,200 pg/ml was 4.00 (p=0.037).

CONCLUSIONS

Serum levels of Ang-2 in multi-trauma patients are increased upon advent of septic complications and they are connected with bad prognosis. Its exact role in the process of multiple trauma remains to be defined.

Temporary stenting of acquired benign tracheoesophageal fistulas in critically ill ventilated patients

BACKGROUND

To evaluate the use of esophageal stents for temporary sealing of acquired benign tracheoesophageal fistulas developed in critically ill, ventilated patients.

METHODS

This is a retrospective analysis (1992-2003) of the data of 12 mechanically ventilated patients - six of them after major or multiple trauma - being intubated for a median of 30 days before they develop an acquired benign tracheoesophageal fistula. Five of them were in sepsis. Two types of stents were used: the Wilson-Cook esophageal balloon plastic stent in the first four cases and the Ultraflex covered self-expandable stent in the remaining eight. The total procedure was performed at bedside in the intensive care unit, with no special need for supplementary anesthesia or fluoroscopic control.

RESULTS

Stent implantation was technically successful in all patients and fistula occlusion was achieved in every case. There was no stent migration and fistulas remained sealed until death or upon decision for removal. Nine patients died between 5 days and 2 months after stent placement, as a result of their diseases. Three patients were referred for fistula surgical repair 33, 36, and 43 days after stent placement. Before surgery the stents were easily removed under direct vision.

CONCLUSION

Temporary closure of an acquired tracheoesophageal fistula developed in critically ill ventilated patients is an easy, bedside-applicable, safe, and effective palliative procedure, with no complications or mortality.

Oxidative stress due to anesthesia and surgical trauma: importance of early enteral nutrition

Anesthesia and surgical trauma are considered major oxidative and nitrosative stress effectors resulting in the development of SIRS. In this study we evaluated the usefulness of early enteral nutrition after surgical trauma. Sixty male Wistar rats were subjected to midline laparotomy and feeding-gastrostomy. Twenty of these rats served as controls after recovering from the operation stress. The remaining rats received, through gastrostomy, enteral nutrition or placebo-feeding for 24 h. Oxidative stress markers and CC chemokine production were evaluated in rat serum and liver tissue. The operation itself was found to increase nitric oxide (NO) and malondialdehyde (MDA) and to decrease superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), as well as liver tissue energy charge (EC) in relation to controls. The rats receiving enteral feeding exhibited statistically significantly lower levels of NO and MDA, and higher levels of SOD, GSH-Px, and liver EC, in relation to placebo feeding rats. The operation significantly increased the chemokines monocyte chemoattractant protein (MCP)-1 and regulated upon activation, normal T-cell expressed, and secreted (RANTES) in rat serum, while enteral nutrition caused a further significant increase in chemokine levels in serum. mRNA chemokine expression in liver was increased in a similar pattern. These findings indicate that early enteral feeding might play an important role after surgery ameliorating oxidative stress, affecting positively the hepatic EC and regulating, via chemokine production, cell trafficking, and healing process.

Deterioration of visceral perfusion caused by intra-abdominal hypertension in pigs ventilated with positive end-expiratory pressure

Experimental studies and clinical experience suggest that the combination of positive end-expiratory pressure (PEEP) ventilation and intra-abdominal hypertension might alter splanchnic hemodynamics to a significantly greater degree than the effect of either of them alone. Therefore, we assessed the intestinal and hepatic hemodynamics in two steps of PEEP ventilation, adding tense pneumoperitoneum in a pig model. The hepatic artery, portal vein, and superior mesenteric artery blood flow, as well as the hepatic and intestinal mucosal microcirculation, and the hepatic pO2 and intestinal mucosal pH, were assessed before, then with 5 cmH2O and 10 cmH2O PEEP alone, and in combination with a 12-mmHg pneumoperitoneum, in ten domestic pigs. Statistical analysis of the hepatic and intestinal measurements revealed a significant decrease (P = 0.001) in all parameters in relation to the baseline, during the 5-cmH2O and 10-mmH2O PEEP ventilation period. The addition of 12 mmHg intra-abdominal pressure led to an extreme deterioration in all parameters (P = 0.001), in relation to both the baseline and the 10-cmH2O PEEP measurement. These findings demonstrate that PEEP and intra-abdominal hypertension act cumulatively on the abdominal viscera, producing conditions of extremely low hypoperfusion and ischemia.

Obesity as a consequence of gut bacteria and diet interactions

Obesity is a major public health concern, caused by a combination of increased consumption of energy-dense foods and reduced physical activity, with contributions from host genetics, environment, and adipose tissue inflammation. In recent years, the gut microbiome has also been found to be implicated and augmented research in mice and humans have attributed to it both the manifestation and/or exacerbation of this major epidemic and vice versa. At the experimental level, analysis of fecal samples revealed a potential link between obesity and alterations in the gut flora (drop in Bacteroidetes and increase in Firmicutes), the specific gut microbiome being associated with the obese phenotype. Conventionally raised mice were found to have over 40% more total body fat compared with those raised under germ-free conditions, while conventionalization of germ-free mice resulted in a significant increase in total body fat. Similarly, the sparse data in humans supports the fact that fat storage is favoured by the presence of the gut microbiota, through a multifaceted mechanism. Efforts to identify new therapeutic strategies to modulate gut microbiota would be of high priority for public health, and to date, probiotics and/or prebiotics seem to be the most effective tools.

Gut microbiome, surgical complications and probiotics

The trigger for infectious complications in patients following major abdominal operations is classically attributed to endogenous enteral bacterial translocation, due to the critical condition of the gut. Today, extensive gut microbiome analysis has enabled us to understand that almost all "evidence-based" surgical or medical intervention (antibiotics, bowel preparation, opioids, deprivation of nutrition), in addition to stress-released hormones, could affect the relative abundance and diversity of the enteral microbiome, allowing harmful bacteria to proliferate in the place of depressed beneficial species. Furthermore, these bacteria, after tight sensing of host stress and its consequent humoral alterations, can and do switch their virulence accordingly, towards invasion of the host. Probiotics are the exogenously given, beneficial clusters of live bacteria that, upon digestion, seem to succeed in partially restoring the distorted microbial diversity, thus reducing the infectious complications occurring in surgical and critically ill patients. This review presents the latest data on the interrelationship between the gut microbiome and the occurrence of complications after colon surgery, and the efficacy of probiotics as therapeutic instruments for changing the bacterial imbalance.

Endoprosthesis implantation at the pharyngo-esophageal level: Problems, limitations and challenges

AIM: To present our experience with endoscopic placement of an esophageal endoprosthesis in 19 patients.

METHODS: A retrospective evaluation was made for the use of 19 stents positioned at the level of the cervical esophagus: 11 for malignant tumours (7 causing obstruction, 4 complicated by an esophago -tracheal or -cutaneous fistula), and 8 for an acquired benign tracheo-esophageal fistula due to prolonged intubation. The covered Ultraflex stent was used in all cases except two. These two patients had an esophagocutaneous fistula following laryngectomy and a Flamingo Wall stent was used.

RESULTS: Stent implantation was technically successful in all patients. Dysphagia score was improved from 3 to 2 in stenosis patients, while sealing of the fistula was achieved in all cases. The median hospital stay was 3 d for malignant tumour patients and 13.5 d for esophagocutaneous fistula patients. One Ultraflex stent and two Flamingo Wall stents were easily removed 33 d and 3 months respectively after implantation when the fistulas had totally occluded.

CONCLUSION: Endoprosthesis implantation for malignancy and/or fistula of malignant or benign origin at the level of the cervical esophagus is an easy, well tolerated, safe and effective procedure with no complications or mortality.

Life-threatening visceral complications after intragastric balloon insertion: Is the device, the patient or the doctor to blame?

Background and aim  Intragastric balloon placement is established as a safe, relatively low-cost and well-tolerated minimally invasive procedure for weight loss, giving encouraging results under the strict prerequisite that the obese patient will enroll in a medically supervised weight loss program. This retrospective study reviews already published cases of severe visceral complications for the purpose of assigning responsibility to the device, the patient, or the doctor. Methods  We reviewed PubMed and Scopus archived publications describing intragastric balloon (BIB/Orbera)-related severe visceral complications, i. e. perforations and obstructions. Results  Twenty-two cases of gastric perforation, two cases of esophageal perforation and 10 cases of bowel obstruction were found. For the gastric perforation the endoscopist was responsible in nine cases, the patient in four, and the balloon itself in nine. For the two cases of esophageal perforation, the endoscopists were responsible, while for the 12 cases of bowel obstruction, the patient was responsible for seven and the device for the other five cases. Conclusion  BIB/Orbera balloon insertion remains a safe procedure, with a minimum of complications related to hollow viscera. Mandatory education and accreditation of physicians dealing with bariatric endoscopy and strict supervision of the obese individuals, while living with the balloon, will eliminate such complications.

A FOUR PROBIOTIC PREPARATION FOR VENTILATOR-ASSOCIATED PNEUMONIA IN MULTI-TRAUMA PATIENTS: RESULTS OF A RANDOMIZED CLINICAL TRIAL

The role of probiotics for the prevention of ventilator-associated pneumonia remains inconclusive. Our aim was to assess the efficacy of a probiotics regimen for VAP prophylaxis in mechanically ventilated multi-trauma patients, intubated immediately after the injurious insult. In a randomized, placebo-controlled study enrolling multi-trauma patients, anticipated to require mechanical ventilation for more than 10 days were randomly assigned to receive prophylaxis either with a probiotic formula [n=59] or placebo [n=53]. The probiotic formula was a preparation of Lactobacillus acidophilus LA-5 (1.75 × 10⁹ cfu), L. plantarum (0.5 × 10⁹ cfu), B. lactis BB-12 (1.75 × 10⁹ cfu) and S. boulardii (1.5 × 10⁹ cfu) per sachet. Each patient received two sachets twice daily for 15 days; one through the nasogastric tube; and another spread on the oropharynx. The incidence of VAP was the primary endpoint. The incidence of other infections and sepsis and the duration of hospital stay were the secondary endpoints. Probiotics administration reduced notably the incidence of VAP [11.9% vs 28.3%, odds ratio 0.34, 95%CIs 0.13-0.92, p=0.034] and of sepsis [6.8% vs 24.5%, OR 0.22, 95% CIs 0.07-0.74, p=0.016]. Furthermore, probiotics prophylaxis decreases the time of stay in the intensive care unit (ICU) and of hospital stay. The prophylactic use of probiotics as a combination of enteral and topical application to oropharynx exerted a positive effect on the incidence of VAP and sepsis as well as on the ICU and total hospital stay in patients under protracted mechanical ventilation.