Probiotics and synbiotics for the prevention of postoperative infections following abdominal surgery: a systematic review and meta-analysis of randomized controlled trials

Effects of oral probiotics on inflammation and intestinal function in adult patients after appendectomy: Randomized controlled trial

BACKGROUND

Appendectomy is an acute abdominal surgery that is often accompanied by severe abdominal inflammation. Oral probiotics are one of the postoperative treatments for rapid rehabilitation. However, there is a lack of prospective studies on this topic after appendectomy.

AIM

To investigate whether the postoperative probiotics can modulate the inflammatory response and restore intestinal function in patients following appendectomy.

METHODS

This was a prospective, randomized trial. A total of 60 emergency patients were randomly divided into a control group (n = 30) and a probiotic group (n = 30). Patients in the control group started to drink some water the first day after surgery, and those in the probiotic group were given water supplemented with Bacillus licheniformis capsules for 5 consecutive days postsurgery. The indices of inflammation and postoperative conditions were recorded, and the data were analyzed with RStudio 4.3.2 software.

RESULTS

A total of 60 participants were included. Compared with those in the control group, the C-reactive protein (CRP), interleukin 6 and procalcitonin (PCT) levels were significantly lower in the probiotic group at 2 d after surgery (P = 2.224e-05, P = 0.037, and P = 0.002, respectively, all P < 0.05). This trend persisted at day 5 post-surgery, with CRP and PCT levels remaining significantly lower in the probiotic group (P = 0.001 and P = 0.043, both P < 0.05). Furthermore, probiotics resulted in a shorter time to first flatus and a greater percentage of gram-negative bacilli in the feces (P = 0.035, P = 0.028, both P < 0.05).

CONCLUSION

Postoperative oral administration of probiotics may modulate the gut microbiota, benefit the recovery of the early inflammatory response, and subsequently enhance recovery after appendectomy.

The Role of Probiotics in Inflammation Associated with Major Surgery: A Narrative Review

Background: Gut microbiota is well-known for its ability to maintain intestinal homeostasis. However, the disruption of this homeostasis, known as dysbiosis, leads to multiple consequences, including local and systemic inflammation. Surgery-induced inflammation is a major concern for patients, as it leads to many infectious and non-infectious complications. Objective: The purpose of this review was to explore the role of probiotics and symbiotics in surgery-induced inflammation and to determine if their use is effective in combatting inflammation and its complications Methods and Materials: A literature search was conducted, and articles published only in English, until December 2022 were included. The results are reported in the form of a narrative review. Results: The perioperative use of probiotics and/or symbiotics results in lower risk of infectious complications, including reduced rates of surgical site infections, respiratory and urinary tract infections, shorter hospital stays, and fewer days of antibiotic administration. It also contributes to reducing non-infectious complications, as it mitigates systemic and local inflammation via maintenance of the intestinal barrier, improves intestinal mobility, and is associated with lower rates of postoperative pain and anastomotic leak. Conclusions: Restoring gut microbiota after disruptions caused by surgery may accelerate local healing processes, attenuate systemic inflammation, and may thus prove beneficial to certain populations.

Role of Probiotics and Synbiotics in Preventing Chemoradiotherapy-Associated Toxicity in Colorectal Cancer Patients: A Systematic Review

Background

Previous studies found that the use of probiotics may have a protective effect on chemotherapy-associated toxicity in cancer patients. A systematic review was conducted to evaluate the effect of probiotics and synbiotics on chemoradiotherapy-associated toxicity in colorectal cancer (CRC) patients.

Methods

A systematic review of randomized controlled trials (RCTs) was performed to assess the effect of probiotics and synbiotics in CRC patients undergoing chemotherapy. All RCTs in English, up to January 2021, were included through a literature search in Scopus, Google Scholar, PubMed (PMC Central, MEDLINE), ClinicalTrials.gov, and ProQuest databases. The impact of probiotics and synbiotics on the side effects associated with chemotherapy, radiotherapy, and chemoradiotherapy in CRC patients was evaluated. The quality of the RTCs was independently assessed by two reviewers. EndNote X8 software was used to manage the search results.

Results

Of the 904 identified articles, three studies finally met the inclusion criteria and were systematically reviewed. Two studies reported that patients who received probiotics had less abdominal discomfort and required less bowel toxicity-related hospital care. Although probiotic supplementation lowered radiation-associated diarrhea, it had no significant effect when anti-diarrheal drugs were used. Another study reported that synbiotic supplementation improved quality of life and marginally reduced diarrhea and serum levels of high-sensitivity C-reactive protein (hs-CRP) and matrix metalloproteinase (MMP-2 and MMP-9).

Conclusion

Probiotics and synbiotics do not have a significant effect on reducing chemotherapy-associated toxicity and diarrhea in CRC patients. These findings should be substantiated by further RCTs with rigorous placebo-controlled studies.

Probiotic supplements and postoperative complications after tooth extractions and third molar surgery: a systematic review

INTRODUCTION

Probiotics have gained considerable attention as intervention for various conditions in dentistry. The purpose of this review is to evaluate the current literature on the efficacy of probiotic supplements for alleviating symptoms after tooth extractions and third molar surgery.

EVIDENCE ACQUISITION

We searched the PubMed and Google Scholar databases up to October 15, 2021 using pertinent keywords to retrieve relevant literature. Based on abstracts, the authors reviewed the full text papers, extracted key outcome data, and assessed the risk of bias.

EVIDENCE SYNTHESIS

Four articles based on three RCT's were included of which three allowed compilation. There were no beneficial effects on the occurrence of postoperative infections or alveolitis, but we disclosed a significant trend towards less self-reported pain one week after the tooth extractions (RD -0.22; 95% CI -0.33; -0.11; P<0.05). Findings concerning swelling, discomfort and use of painkillers were inconsistent.

CONCLUSIONS

Probiotic supplements may offer clinical benefits within oral surgery, such as alleviating pain after tooth extractions. However, the certainty of these findings was very low due to risk of bias, heterogeneity, and inconsistencies across the studies. Further and larger investigations are required to strengthen the level of evidence.

Study on Risk Factors and Nutritional Status of Postoperative Infection in Patients Undergoing Abdominal Surgery

In order to evaluate the risk factors of postoperative infection in patients undergoing abdominal surgery and the correlation with nutritional status, 143 patients admitted to our hospital for abdominal surgery from September 2020 to September 2021 are selected and analyzed. By collecting the clinical results and related pathological data of all patients, all patients are divided into the postoperative infection group (48 cases) and the noninfection group (95 cases) according to whether postoperative infection occurred. Firstly, the clinical data of the two groups are analyzed by univariate analysis. Secondly, the risk factors of postoperative infection in patients undergoing abdominal surgery are analyzed by binary logistic regression. Thirdly, the nutrition-related indexes are compared, and the correlation between postoperative infection and serum nutritional indexes is analyzed by the Spearman correlation coefficient. The results demonstrate that patients undergoing abdominal surgery have a certain risk of infection after surgery, and combination with underlying diseases is a risk factor for postoperative infection. In addition, poor preoperative nutritional status is also closely related to postoperative infection. It is suggested that serum PA and RBP indicators have certain predictive effects on postoperative infection.

Probiotics or Synbiotics for Preventing Postoperative Infection in Hepatopancreatobiliary Cancer Patients: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Postoperative infection of hepatopancreatobiliary cancer (HPBC) is a major cause of morbidity and mortality. Probiotics and synbiotics are potential prevention strategies, but evidence on the efficacy of probiotics or synbiotics in the prevention of postoperative infection for HPBC remains controversial. This study aimed to define the impact of probiotics or synbiotics on the incidence of postoperative infection in HPBC patients.

METHODS

A systematic search of the Cochrane Library, PubMed, Embase, and Web of Science databases was conducted from inception to February 2, 2021 to identify randomized controlled trials (RCTs) evaluating the efficacy of probiotics or synbiotics in HPBC. Data were pooled and expressed as the risk ratio (RR) and mean difference (MD) with 95% confidence intervals.

RESULTS

Eight RCTs involving 445 participants were included. Supplementation with probiotics or synbiotics significantly reduced the incidence of postoperative infection (RR 0.55) in HPBC patients, and both probiotics (RR 0.68) and synbiotics (RR 0.41) were effective in reducing the incidence of postoperative infection. In addition, probiotics or synbiotics can reduce duration of antibiotic use (MD -3.52) and length of hospital stay (MD -4.21).

CONCLUSION

Probiotics or synbiotics are effective strategies for the prevention of postoperative infection in HPBC patients.

Composite Inflammatory Indicators as Early Predictor of Intra-abdominal Infections after General Surgery

Objective

To identify rapid and accurate early diagnostic indicators for intra-abdominal infection (IAI) after general surgery.

Methods

We conducted a retrospective analysis of 3,810 general surgical patients in our hospital from August 2017 to July 2018. The predictive value of PCT, CRP, TNFα, and IL6 on postoperative days (PODs) 1 and 3 and composite indicators for complicated IAIs among surgical patients was clarified.

Results

There were 271 patients in the infected group and 614 patients in the uninfected group using IAI diagnostic criteria in this study. CRP, PCT, TNFα, and IL6 in the infected group were significantly higher than the uninfected group on POD1 and POD3. In the infected group, the composition of the four indicators on POD1 (AUC 0.819) and POD3 (AUC 0.848) showed higher predictive efficiency than the individual indicators (AUC 0.670-0.805).

Conclusion

The composite of CRP, PCT, TNFα, and IL6 can be used as a predictor of postoperative abdominal infectious complications with high sensitivity and specificity on POD1 and POD3, which can provide a basis for early diagnosis of postoperative abdominal infectious complications.

Do patients fed enterally post-gastrointestinal surgery experience more complications when fed a fiber-enriched feed compared with a standard feed? A systematic review

The role of enteral feeding with fiber-enriched feeds in minimizing infections, shortening length of hospital stay (LOHS), and preventing or treating feeding complications has been widely researched. However, there is limited evidence to evaluate the role of fiber-enriched enteral feeding in gastrointestinal surgery patients postoperatively. This systematic review aims to identify the role of fiber-enriched enteral feeds on postoperative feeding complications of diarrhea, nausea and vomiting, abdominal distension, flatulence, cramps, LOHS, and infection rates after gastrointestinal surgery. A systematic literature search was conducted using MEDLINE, CINAHL, and Cochrane Library. Manual reference lists were searched on identified studies and the SCOPUS database. Randomized controlled trials (RCTs) conducted on any gastrointestinal surgery type that included enteral nutrition with high-fiber enteral feeds and/or fiber supplements were included. All studies included were screened for risk of bias with Cochrane's risk-of-bias tool, and data were extracted with Cochrane Collaboration's data extraction tool. In total, 3 RCTs out of 231 screened citations including fiber-enriched feeds and probiotics were included in this review. No significant effect on LOHS or postoperative infections was found. No safety risks were identified. Limited, low-quality evidence suggests fiber-enriched feeds may minimize diarrhea incidence. The effects of fiber-enriched feeds postoperatively in gastrointestinal surgery remain under-researched. Studies evaluating fiber and probiotics were low quality and at high risk of bias because of the misreporting of outcomes and the lack of detailed outlines of probiotic strains utilized. However, fiber-enriched enteral feeding appears safe, may yield benefits, and is recommended in stable gastrointestinal surgical patients.

Role of probiotics in patients with colorectal cancer: a systematic review protocol of randomised controlled trial studies

INTRODUCTION

Colorectal cancer is one of the leading causes of cancer-related morbidity worldwide and it has been reported to be associated with poor lifestyle habits which include excess tobacco and alcohol intake as well as genetics and age factors. Probiotics such as the lactic acid bacteria and Bifidobacterium as well as probiotic containing foods (kombucha, kefir, miso etc) have received lots of attention as anticancer agents for prevention and treatment. The effects of the administration of probiotics to patients with colorectal cancer is the primary goal of this systematic review. The overall aim is to assess how the use of probiotics in patients with colorectal cancer helps in the management of colorectal cancer and its effect on the diversity of gut microbiota. The final systematic review will provide a comprehensive evidence base for the use and efficacy of probiotics in patient with colorectal cancer care.

METHODS AND ANALYSIS

The systematic review, will be conducted by extensively searching different databases such as PubMed, Web of Science, Scopus, Wiley and ProQuest to identify randomised controlled trials (with no time frame) which relate to the administration of probiotics to patients with colorectal cancer. The search strategy will include words like colorectal cancer, probiotics, Bifidobacterium, clinical trials etc. A systematic search of databases was performed between 17 and 20 January 2020. Two reviewers will independently review the studies and also search the reference lists of the eligible studies to obtain more references. Data will be extracted from the eligible studies using standardised data extraction form. After assessing the risk of bias, qualitative analysis will be used to synthesise the systematic review.

ETHICS AND DISSEMINATION

This is a protocol for a systematic review; therefore, it doesn't require any ethics approval. We intend to disseminate the protocol in a peer reviewed journal.

GRADE-Leitlinien: 17. Beurteilung des Bias-Risikos durch fehlende Endpunkt-Daten im Evidenzkörper

OBJECTIVE

To provide GRADE guidance for assessing risk of bias across an entire body of evidence consequent on missing data for systematic reviews of both binary and continuous outcomes.

STUDY DESIGN AND SETTING

Systematic survey of published methodological research, iterative discussions, testing in systematic reviews, and feedback from the GRADE Working Group.

RESULTS

Approaches begin with a primary meta-analysis using a complete case analysis followed by sensitivity meta-analyses imputing, in each study, data for those with missing data, and then pooling across studies. For binary outcomes, we suggest use of "plausible worst case" in which review authors assume that those with missing data in treatment arms have proportionally higher event rates than those followed successfully. For continuous outcomes, imputed mean values come from other studies within the systematic review and the standard deviation (SD) from the median SDs of the control arms of all studies.

CONCLUSIONS

If the results of the primary meta-analysis are robust to the most extreme assumptions viewed as plausible, one does not rate down certainty in the evidence for risk of bias due to missing participant outcome data. If the results fail to prove robust to plausible assumptions, one would rate down certainty in the evidence for risk of bias.

The effect of preoperative synbiotic treatment to prevent surgical-site infection in hepatic resection

We aimed to clarify the influence of preoperative synbiotic therapy on surgical-site infections (SSIs) after hepatic resection. Between January 2011 and December 2017, 284 patients who underwent hepatic resection without biliary tract reconstruction and resection of other organs were included. We prospectively administered Clostridium butyricum and partially hydrolyzed guar gum before hepatic resection between April 2016 and December 2017 (synbiotic group). One-hundred-fifteen patients of the synbiotic group and 169 patients (conventional group) treated between January 2011 and the end of March 2016 were compared using propensity score matching. The frequency of laparoscopic resection was significantly larger in the synbiotic group (conventional group; 28% vs synbiotic group; 55%, p<0.001) and the amount of intraoperative bleeding was significantly smaller in the synbiotic group (median; conventional group, 700 ml vs synbiotic group, 200 ml; p<0.001). The postoperative SSI was significantly lower in the synbiotic group of six patients (5.2%) than in the conventional group of 30 patients (17.8%) (p = 0.002). Sixty patients in each group remained after propensity score matching. There was no significant difference in the incidence of SSI between the groups (conventional group, 15% vs synbiotic group, 6.7%; p = 0.239). In conclusion, preoperative synbiotic treatment did not reduce SSIs after hepatic resection.

Gut microbiota in neonates with congenital gastrointestinal surgical conditions: a prospective study

BACKGROUND

There is limited information on gut microbiota of neonates with congenital gastrointestinal surgical conditions (CGISCs) available.

METHODS

This study compared stool microbiota and short-chain fatty acids (SCFAs) of 37 term infants with CGISCs with 36 term healthy infants (HIs). Two stool samples were collected from each infant: as soon as possible after birth (week 1) and 10-14 days of life (week 2).

RESULTS

Bacterial richness and alpha diversity were comparable between CGISCs and HIs at week 1 and week 2 (all p > 0.05). Beta diversity analysis revealed that at week 1, CGISCs had similar community structures to HIs (p = 0.415). However, by week 2, community structures of CGISCs were significantly different from HIs (p = 0.003). At week 1, there were no significant differences in the relative abundances of genera Bifidobacterium and Bacteroides between CGISCs and HIs. At week 2, the relative abundance of Bifidobacterium was significantly lower in CGISCs (mean percentage 7.21 ± 13.49 vs. 28.96 ± 19.6; p = 0.002). Bacteroides were also less abundant in the CGISC group (mean percentage 0.12 ± 0.49 vs. 6.59 ± 8.62; p = 0.039). Relative abundance of genera Pseudomonas and Escherichia-Shigella were higher in CGISCs. At week 2, stool concentrations of all SCFAs were lower in CGISCs (all p < 0.001).

CONCLUSIONS

During hospitalization, neonates with CGISCs develop gut dysbiosis and deficiency of SCFAs.

IMPACT

During hospitalisation, neonates with congenital gastrointestinal surgical conditions develop gut dysbiosis with deficiency of Bifidobacteria and Bacteroides and increased abundance of Escherichia-Shigella and Pseudomonas. They also have low levels of short chain fatty acids in their stools compared to healthy infants. This is the first study evaluating the gut microbiota using 16S ribosomal RNA sequencing methods and stool short chain fatty acids in neonates with congenital gastrointestinal surgical conditions and comparing them to healthy infants. The findings of this study will pave the way for randomised trials of bifidobacterial supplementation in neonates with congenital gastrointestinal surgical conditions.

Post-surgical intestinal dysbiosis: use of an innovative mixture (Lactobacillus plantarum LP01, Lactobacillus lactis subspecies cremoris LLC02, Lactobacillus delbrueckii LDD01)

Abdominal surgery represents a high risk for hospital-acquired infections and complication that may compromise the surgery outcome. Patients with recent abdominal surgery have an intestinal dysbiosis. There is evidence that probiotics may counterbalance the impaired microbiota. Therefore, the current survey evaluated the efficacy and safety of Abincol®, an oral nutraceutical containing a probiotic mixture with Lactobacillus plantarum LP01 (1 billion of living cells), Lactobacillus lactis subspecies cremoris LLC02 (800 millions of living cells), and Lactobacillus delbrueckii LDD01 (200 millions of living cells), in 612 outpatients (344 males and 268 females, mean age 58 years) undergoing digestive surgery. Patients took 1 stick/daily for 8 weeks. Abincol® significantly diminished the presence and the severity of intestinal symptoms and improved stool form. In conclusion, the current survey suggests that Abincol® may be considered an effective and safe therapeutic option in the management of patients undergoing digestivesurgery.

Probiotic research in neonates with congenital gastrointestinal surgical conditions - Now is the time

Neonates with congenital gastrointestinal surgical conditions (CGISC) receive parenteral nutrition, get exposed to multiple courses of antibiotics, undergo invasive procedures, and are nursed in intensive care units. They do not receive early enteral feeding and have limited opportunities for skin to skin contact with their mothers. Many of these infants receive gastric acid suppression therapies. All these factors increase the risk of gut dysbiosis in these infants. Gut dysbiosis is known to be associated with increased risk of infections and other morbidities in ICU patients. Experimental studies have shown that probiotics inhibit gut colonization with pathogenic bacteria, enhance gut barrier function, facilitate colonization with healthy commensals, protect from enteropathogenic infection through production of acetate, reduce antimicrobial resistance, enhance innate immunity, and increase the maturation of the enteric nervous system and promote gut peristalsis. Through these mechanisms, probiotics have the potential to decrease the risk of sepsis and inflammation, improve feed tolerance and minimise cholestasis in neonates with CGISC. Among preterm non-surgical infants, evidence from more than 35 RCTs and multiple observational studies have shown probiotics to be safe and beneficial. A RCT in neonates (N=24) with gastroschisis found that probiotic supplementation partially attenuated gut dysbiosis. Two ongoing RCTs (total N=168) in neonates with gastrointestinal surgical conditions are expected to provide feasibility data to enable the conduct of large RCTs. Rigorous quality assurance of the probiotic product, ongoing microbial surveillance and clinical vigilance are warranted while conducting such RCTs.

A Systematic Review, Meta-Analysis, and Meta-Regression Evaluating the Efficacy and Mechanisms of Action of Probiotics and Synbiotics in the Prevention of Surgical Site Infections and Surgery-Related Complications

Intestinal microbiota play an important role in the pathogenesis of surgical site infections (SSIs) and other surgery-related complications (SRCs). Probiotics and synbiotics were found to lower the risk of surgical infections and other surgery-related adverse events. We systematically reviewed the approach based on the administration of probiotics and synbiotics to diminish SSIs/SRCs rates in patients undergoing various surgical treatments and to determine the mechanisms responsible for their effectiveness. A systematic literature search in PubMed/MEDLINE/Cochrane Central Register of Controlled Trials from the inception of databases to June 2018 for trials in patients undergoing surgery supplemented with pre/pro/synbiotics and randomized to the intervention versus placebo/no treatment and reporting on primarily: (i) putative mechanisms of probiotic/symbiotic action, and secondarily (ii) SSIs and SRCs outcomes. Random-effect model meta-analysis and meta-regression analysis of outcomes was done. Thirty-five trials comprising 3028 adult patients were included; interventions were probiotics (n = 16) and synbiotics (n = 19 trials). We found that C-reactive protein (CRP) and Interleukin-6 (IL-6) were significantly decreased (SMD: -0.40, 95% CI [-0.79, -0.02], p = 0.041; SMD: -0.41, 95% CI [-0.70, -0.02], p = 0.006, respectively) while concentration of acetic, butyric, and propionic acids were elevated in patients supplemented with probiotics (SMD: 1.78, 95% CI [0.80, 2.76], p = 0.0004; SMD: 0.67, 95% CI [0.37, -0.97], p = 0.00001; SMD: 0.46, 95% CI [0.18, 0.73], p = 0.001, respectively). Meta-analysis confirmed that pro- and synbiotics supplementation was associated with significant reduction in the incidence of SRCs including abdominal distention, diarrhea, pneumonia, sepsis, surgery site infection (including superficial incisional), and urinary tract infection, as well as the duration of antibiotic therapy, duration of postoperative pyrexia, time of fluid introduction, solid diet, and duration of hospital stay (p < 0.05). Probiotics and synbiotics administration counteract SSIs/SRCs via modulating gut-immune response and production of short chain fatty acids.

Impact of the preoperative use of synbiotics in colorectal cancer patients: A prospective, randomized, double-blind, placebo-controlled study

OBJECTIVES

Gastrointestinal microflora is involved in the development and regulation of the immune response. Non-pathogenic bacteria are important to prevent the development and subsequent invasion of enteropathogenic bacteria. Surgical trauma and intestinal preparation can disrupt the intestinal microbiota balance. Modulating the microbiota in the preoperative period in patients with colorectal cancer may have an effect on the occurrence of postoperative complications. The aim of this study was to assess the effect of preoperative synbiotic administration in patients with colorectal cancer subjected to colorectal resection.

METHODS

This was a prospective, randomized, double-blind, placebo-controlled study of 73 patients with colorectal cancer. Eight days before surgery, patients were randomized to receive either synbiotics (Simbioflora, Farmoquimica, São Paulo, Brazi) or placebo (maltodextrin). The envelopes were identical and labeled A or B. All patients underwent nutritional assessment and measurements of C-reactive protein (CRP), interleukin (IL)-6, serum albumin, and transferrin. Patients were given a diluted envelope in 100 mL of water twice daily for 7 d. The occurrence of infectious or non-infectious complications, time of antibiotic use, duration of hospitalization, and occurrence of deaths were recorded for 30 d postoperatively.

RESULTS

Mean age, demographic data, and tumor staging were similar between the groups at baseline. After 7 d of synbiotic intake, there were significant reductions in IL-6 levels (163.2 ± 19.5 versus 138.8 ± 12.5, P < 0.001) and CRP (10 ± 5.2 versus 7.17 ± 3.2, P < 0.001), whereas the control group did not present significant changes I IL-6 levels (154.2 ± 18.3 versus 160.9 ± 18.6, NS) or CRP (10.6 ± 6.18 versus 10.4 ± 6.1, NS). Serum albumin and transferrin did not show significant changes. Postoperative infectious complications occurred in 2.8% of patients in the synbiotic group and in 18.9% of the control group (P = 0.02). The mean antibiotic usage time was 1.42 ± 0.5 d in the synbiotic group and 3.74 ± 4.3 d in the control group (P < 0.001). The mean hospital length of stay was 3 ± 1 d in the synbiotic group and 4 ± 18 in the control group (P < 0.001). Three deaths were reported in the control group and none in the synbiotic group (P = 0.115).

CONCLUSIONS

The use of synbiotics for 7 d preoperatively in patients with colorectal cancer attenuates the inflammatory state and is associated with reductions in morbidity, hospital length of stay, and use of antibiotics.

Acid-Suppressive Therapy and Risk of Infections: Pros and Cons

This narrative review summarises the benefits, risks and appropriate use of acid-suppressing drugs (ASDs), proton pump inhibitors and histamine-2 receptor antagonists, advocating a rationale balanced and individualised approach aimed to minimise any serious adverse consequences. It focuses on current controversies on the potential of ASDs to contribute to infections-bacterial, parasitic, fungal, protozoan and viral, particularly in the elderly, comprehensively and critically discusses the growing body of observational literature linking ASD use to a variety of enteric, respiratory, skin and systemic infectious diseases and complications (Clostridium difficile diarrhoea, pneumonia, spontaneous bacterial peritonitis, septicaemia and other). The proposed pathogenic mechanisms of ASD-associated infections (related and unrelated to the inhibition of gastric acid secretion, alterations of the gut microbiome and immunity), and drug-drug interactions are also described. Both probiotics use and correcting vitamin D status may have a significant protective effect decreasing the incidence of ASD-associated infections, especially in the elderly. Despite the limitations of the existing data, the importance of individualised therapy and caution in long-term ASD use considering the balance of benefits and potential harms, factors that may predispose to and actions that may prevent/attenuate adverse effects is evident. A six-step practical algorithm for ASD therapy based on the best available evidence is presented.

Synbiotics for Improved Human Health: Recent Developments, Challenges, and Opportunities

Research on combining pro- and prebiotics as synbiotics to enhance human and animal health has accelerated in the past 10 years, including many clinical trials that have assessed a diverse range of synbiotic formulations. In this review, we summarize these studies as well as the commercial applications of synbiotics that are available. In particular, we critically assess the claimed health benefits of synbiotic applications and the ecological and therapeutic factors to consider when designing synbiotics and discuss the implications of these concepts for future research in this field.

Evidence-Based Support for Nutrition Therapy in Head and Neck Cancer

PURPOSE OF REVIEW

Patients diagnosed with head and neck (H&N) cancer often present in a malnourished state for varied reasons; nutritional optimization is therefore critical to the success of treatment for these complex patients. This article aims to review the current nutrition literature pertaining to H&N cancer patients and to present evidence-based strategies for nutritional support specific to this population.

RECENT FINDINGS

Aggressive nutritional intervention is frequently required in the H&N cancer patient population. Rehabilitating nutrition during operative and nonoperative treatment improves compliance with treatment, quality of life, and clinical outcomes. When and whether to establishing alternative enteral access are points of controversy, although recent evidence suggests prophylactic enteral feeding tube placement should not be universally applied. Perioperative nutritional optimization including preoperative carbohydrate loading and provision of arginine-supplemented immunonutrition has been shown to benefit at-risk H&N cancer patients.

SUMMARY

With multidisciplinary collaboration, H&N cancer patients can receive individualized nutritional support to withstand difficult cancer treatment regimens and return to acceptable states of nutritional health.

GRADE guidelines 17: assessing the risk of bias associated with missing participant outcome data in a body of evidence

OBJECTIVE

To provide GRADE guidance for assessing risk of bias across an entire body of evidence consequent on missing data for systematic reviews of both binary and continuous outcomes.

STUDY DESIGN AND SETTING

Systematic survey of published methodological research, iterative discussions, testing in systematic reviews, and feedback from the GRADE Working Group.

RESULTS

Approaches begin with a primary meta-analysis using a complete case analysis followed by sensitivity meta-analyses imputing, in each study, data for those with missing data, and then pooling across studies. For binary outcomes, we suggest use of "plausible worst case" in which review authors assume that those with missing data in treatment arms have proportionally higher event rates than those followed successfully. For continuous outcomes, imputed mean values come from other studies within the systematic review and the standard deviation (SD) from the median SDs of the control arms of all studies.

CONCLUSIONS

If the results of the primary meta-analysis are robust to the most extreme assumptions viewed as plausible, one does not rate down certainty in the evidence for risk of bias due to missing participant outcome data. If the results prove not robust to plausible assumptions, one would rate down certainty in the evidence for risk of bias.

Probiotic supplementation in neonates with major gastrointestinal surgical conditions: a systematic review

OBJECTIVES

Neonates with major gastrointestinal surgical conditions frequently suffer from prolonged feed intolerance, infections, and need multiple courses of antibiotics. All these put them at risk of gut dysbiosis. Probiotic supplementation has the potential to minimise dysbiosis and improve clinical outcomes in such infants. Hence, we aimed to conduct a systematic review of probiotics in neonates with major surgical conditions of the gut.

METHODS

Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and other databases were searched in September 2016.

RESULTS

Two randomised controlled trials (RCTs) were included; the first was conducted in 24 neonates with gastroschisis, the second in eight neonates with various surgical conditions. In the first study, the overall microbial communities were not significantly different between groups, though analysis of the final specimens demonstrated higher Bifidobacteriaceae, lower Clostridiaceae, and trends toward lower Enterobacteriaceae, Enterococcaceae, Staphylococcaceae, and Streptococcaceae in the probiotic group. In the second study, there were significantly more Streptcoccaceae in the faecal samples in the probiotic group and significantly more Bifidobacteriaceae in the no probiotic group (p < .05).

CONCLUSIONS

There is limited evidence regarding the role of probiotics in neonates with gastrointestinal surgical conditions. Adequately powered RCTs are needed to address this issue.

A randomized clinical trial on the effectiveness of a symbiotic product to decolonize patients harboring multidrug-resistant Gram-negative bacilli

INTRODUCTION:

We aimed to evaluate the effectiveness of a symbiotic product to decolonize the intestinal tract of patients harboring multidrug-resistant (MDR) Gram-negative bacilli and to prevent nosocomial infections.

METHODS:

This was a randomized, double blind, placebo-controlled clinical trial, conducted in a tertiary-care university hospital. All adult hospitalized patients with a positive clinical culture and a positive rectal swab for any MDR Gram-negative bacilli were potentially eligible. Exclusion criteria were pregnancy, immunosuppression, and bowel obstruction/perforation. The intervention consisted of administering a symbiotic product (Lactobacillus bulgaricus, Lactobacillus rhamnosus, and fructo-oligosaccharides) twice a day for seven days via the oral/enteral route.

RESULTS:

Between August 1, 2012 and December 22, 2013, 116 of 275 eligible patients were allocated to treatment (n=57) and placebo (n=59). Overall, 101 patients received at least four doses of the study products and were included in the modified intention-to-treat analysis. The primary study outcome, a negative rectal swab for MDR Gram-negative bacilli after treatment, was identified in 16.7% (8/48) and 20.7% (11/53) of patients in the experimental and placebo group, respectively (p=0.60). The secondary outcome, the combined incidence of nosocomial respiratory and urinary tract infections, was 37.5% (18/48) in the experimental group versus 22.6% (12/53) in the control group (adjusted odds ratio: 1.95, 95% confidence interval: 0.69-5.50, p=0.21). Length of stay after the beginning of the intervention, incidence of adverse events, and in-hospital mortality rates were similar in both study groups.

CONCLUSIONS:

Under the present study conditions, symbiotic administration was not effective for decolonizing hospitalized patients harboring MDR Gram-negative bacilli.

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.

Can Probiotics Improve Your Surgical Outcomes?

Despite ongoing advances in medical technology, postoperative infections and infectious complications continue to be a significant cause of morbidity and mortality. Surgical trauma and prophylactic antibiotics disrupt the balance of the intestinal microbiota and barrier function of the gut, potentiating an enhanced inflammatory response and further immune system depression. With the increasing costs of health care and emergence of multidrug-resistant bacteria, alternative approaches must be explored. Many clinical studies have demonstrated that the use of probiotics, prebiotics, or a combination of both (synbiotics) as a part of innovative strategies can improve outcomes of elective abdominal and gastrointestinal surgical procedures. It has been demonstrated that probiotics play a role in gut barrier improvement and immunomodulation. However, it is evident that additional research is needed including larger, multicenter, randomized controlled trials to validate the safety and efficacy of their use in surgical patients. The purpose of this article is to discuss background of probiotic use in abdominal/gastrointestinal surgery, risk and benefits, clinical relevance for health care providers, and further implications for research.