Bacterobilia in pancreatic surgery-conclusions for perioperative antibiotic prophylaxis

Piperacillin/tazobactam for surgical prophylaxis during pancreatoduodenectomy: meta-analysis

BACKGROUND

Pancreatoduodenectomy is associated with an increased incidence of surgical-site infections, often leading to a significant rise in morbidity and mortality. This trend underlines the inadequacy of traditional antibiotic prophylaxis strategies. Hence, the aim of this meta-analysis was to assess the outcomes of antimicrobial prophylaxis, comparing piperacillin/tazobactam with traditional antibiotics.

METHODS

Upon registering in PROSPERO, the international prospective register of systematic reviews (CRD42023479100), a systematic search of various databases was conducted over the interval 2000-2023. This inclusive search encompassed a wide range of study types, including prospective and retrospective cohorts and RCTs. The subsequent data analysis was carried out utilizing RevMan 5.4.

RESULTS

A total of eight studies involving 2382 patients who underwent pancreatoduodenectomy and received either piperacillin/tazobactam (1196 patients) or traditional antibiotics (1186 patients) as antibiotic prophylaxis during surgery were included in the meta-analysis. Patients in the piperacillin/tazobactam group had significantly reduced incidences of surgical-site infections (OR 0.43 (95% c.i. 0.30 to 0.62); P < 0.00001) and major surgical complications (Clavien-Dindo grade greater than or equal to III) (OR 0.61 (95% c.i. 0.45 to 0.81); P = 0.0008). Subgroup analysis of surgical-site infections highlighted significantly reduced incidences of superficial surgical-site infections (OR 0.34 (95% c.i. 0.14 to 0.84); P = 0.02) and organ/space surgical-site infections (OR 0.47 (95% c.i. 0.28 to 0.78); P = 0.004) in the piperacillin/tazobactam group. Further, the analysis demonstrated significantly lower incidences of clinically relevant postoperative pancreatic fistulas (grades B and C) (OR 0.67 (95% c.i. 0.53 to 0.83); P = 0.0003) and mortality (OR 0.51 (95% c.i. 0.28 to 0.91); P = 0.02) in the piperacillin/tazobactam group.

CONCLUSION

Piperacillin/tazobactam as antimicrobial prophylaxis significantly lowers the risk of postoperative surgical-site infections, major surgical complications (complications classified as Clavien-Dindo grade greater than or equal to III), clinically relevant postoperative pancreatic fistulas (grades B and C), and mortality, hence supporting the implementation of piperacillin/tazobactam for surgical prophylaxis in current practice.

Antibiotic prophylaxis after 48 h postoperatively are not associated with decreased surgical site infections and other healthcare associated infections in pancreatic surgery patients: a retrospective cohort study

BACKGROUND

It is controversial whether antibiotic should be used prophylactically 48 h after pancreatic surgery. Hence, the association of antibiotic prophylaxis (AP) after 48 h postoperatively with the incidence of surgical site infections (SSIs) and other healthcare-associated infections (HAIs) in patients receiving pancreatic surgery was evaluated.

METHODS

A retrospective cohort analysis was performed on 1073 patients who underwent pancreatic surgery. These patients were categorized into the non-AP after 48 h postoperatively group (n = 963) and the AP after 48 h postoperatively group (n = 110) based on whether or not they obtained AP from 48 h to 30 days after surgery. Outcomes included SSIs and other HAIs.

RESULTS

The incidence of SSIs in the non-AP after 48 h postoperatively group (98/963, 10.2%) was notably lower than that in the AP after 48 h postoperatively group (22/110, 20.0%) (P = 0.002). Other HAIs incidence was not significantly different between the non-AP after 48 h postoperatively group (77/963, 8.0%) and the AP after 48 h postoperatively group (11/110, 10.0%) (P = 0.468). Multiple regression analysis demonstrated that AP after 48 h postoperatively was a risk factor for SSIs (OR = 2.14, 95% CI 1.28-3.59) but not for other HAIs (OR = 1.24, 95% CI 0.63-2.42) after adjustment for age, gender, and diabetes. Subsequent to adjustment for all confounding factors, AP after 48 h postoperatively was not a influence factor for SSIs (OR = 2.13, 95% CI 0.76-5.99) and other HAIs (OR = 3.69, 95% CI 0.99-13.81).

CONCLUSIONS

AP after 48 h postoperatively following pancreatic surgery was not associated with the lower morbidity rate of SSIs and other HAIs. Nonetheless, this study may facilitate further development of strategies towards standardization of the duration of AP management of pancreatic surgery.

Alarming correlation between multidrug-resistant bacteriobilia and morbidity after pancreatic surgery

BACKGROUND

Pancreatic surgery is characterized by high morbidity and mortality. Biliary colonization may affect clinical outcomes in these patients.

AIMS

This study aimed to verify whether bacteriobilia and multidrug resistance (MDR) detected during and after pancreatic surgery may have an impact on post-operative outcomes.

METHODS

Data from patients undergoing pancreatic surgery involving bile duct transection (2016-2022) in two high-volume centers were analyzed in relationship to overall morbidity, major morbidity and mortality after pancreato-duodenectomy (PD) or total pancreatectomy (TP). Simple and multivariable regressions were used.

RESULTS

227 patients submitted to PD (n=129) or TP (n=98) were included. Of them, 133 had preoperative biliary drainage (BD; 56.6%), mostly with the employment of endoscopic stents (91.7%). Bacteriobilia was detected in 111 patients (48.9%), and remarkably, observed in patients with BD (p=0.001). In addition, 25 MDR pathogens were identified (22.5%), with a significant prevalence in patients with BD. Multivariable regression analysis showed BD was strongly related to MDR isolation (odds ratio [OR]: 5.61; p=0.010). MDR isolation was the main factor linked to a higher number of major complications (OR: 2.75; p=0.041), including major infection complications (OR: 2.94; p=0.031).

CONCLUSIONS

Isolation of MDR from biliary swab during PD or TP significantly increases the risk of a worse post-operative outcome. Pre-operative precautions could improve patient safety.

Neoadjuvant therapy does not impact the biliary microbiome in patients with pancreatic cancer

BACKGROUND

Pancreatic adenocarcinoma (PDAC) often impinges on the biliary tree and obstruction necessitates stent placement increasing the risk of surgical site infections (SSIs). We sought to explore the impact of neoadjuvant therapy on the biliary microbiome and SSI risk in patients undergoing resection.

METHODS

A retrospective analysis was performed on 346 patients with PDAC who underwent resection at our institution from 2008 to 2021. Univariate and multivariate methods were utilized for analysis.

RESULTS

Biliary stenting rates were similar between groups but resulted in increased bile culture positivity (97% vs. 15%, p < 0.001). Culture positivity did not differ between upfront resection or neoadjuvant chemotherapy (NAC) (77% vs. 80%, p = 0.60). NAC-alone versus neoadjuvant chemoradiotherapy did not impact biliary positivity (80% vs. 79%, p = 0.91), nor did 5-fluorouracil versus gemcitabine-based regimens (73% vs. 85%, p = 0.19). While biliary stenting increased incisional SSI risk (odds ratios [OR]: 3.87, p = 0.001), NAC did not (OR: 0.83, p = 0.54). Upfront resection, NAC, and chemoradiotherapy were not associated with biliary organism-specific changes or antibiotic resistance patterns.

CONCLUSIONS

Biliary stenting is the greatest predictor for positive biliary cultures and SSIs in resected PDAC patients. Neither NAC nor radiotherapy impact bile culture positivity, speciation, rates, or antibiotic resistance patterns, and perioperative antibiotic prophylaxis should not differ.

Pattern of bile cultures and antibiotic sensitivity tests in Sudanese patients diagnosed with obstructive jaundice: A single-center prospective study

Background and Aim

Biliary obstruction causes bacteriobilia and significant morbidity and high mortality, which necessitates prompt and effective treatment for a good clinical outcome. Hence, the aim of this study was to determine updated knowledge of biliary microbial spectrum, antibiotic sensitivity pattern, and key clinical factors of bacteriobilia.

Methods

This is a prospective study conducted during the period between November 2021 and December 2022 at Ibn Sina specialized hospital, Khartoum, Sudan, on 50 patients diagnosed with obstructive jaundice and symptomatic bacteriobilia who underwent open biliary surgeries electively. Bile samples were aspirated intra-operatively and cultured, and antibiotic sensitivity tests were performed.

Results

Fifty-four percent of patients diagnosed with obstructive jaundice who underwent elective open biliary surgeries were males with the ratio (2:1). Forty-six percent of patients were between 61 and 75 years (elderly). The most frequent cause of obstructive jaundice was migrating biliary stones (48% of cases). Thirty-two percent of patients were diabetic with bacteriobilia. The predominant isolated bacterial pathogen in this study was Escherichia coli (36% of cases). These biliary pathogens were sensitive to meropenem in 54% of cases and ciprofloxacin in 46%. Eventually, in all patients in this study, biliary bacterial pathogens were found to be resistant to a broad spectrum of antibiotics.

Conclusion

Careful selection of empirical antibiotic therapy based on surveillance of routine bile cultures during biliary tree procedures in patients with high risk of bacteriobilia will potentially help in improving the surgical outcomes and optimizing treatment of acute cholangitis, which is associated with high mortality.

Risk factors and outcomes for cholangitis after hepatic resection

INTRODUCTION

There is a paucity in the literature in regard to the incidence, risk factors, and outcomes for post-operative cholangitis following hepatic resection.

METHODS

Retrospective review of the ACS NSQIP main and targeted hepatectomy registries for 2012-2016.

RESULTS

A total of 11,243 cases met the selection criteria. The incidence of post-operative cholangitis was 0.64% (151 cases). Multivariate analysis identified several risk factors associated with the development of post-operative cholangitis, stratified out by pre-operative and operative factors. The most significant risk factors were biliary anastomosis and pre-operative biliary stenting with odds ratios (OR) of 32.39 (95% CI 22.91-45.79, P value < 0.0001) and 18.32 (95% CI 10.51-31.94, P value < 0.0001) respectively. Cholangitis was significantly associated with post-operative bile leaks, liver failure, renal failure, organ space infections, sepsis/septic shock, need for reoperation, longer length of stay, increased readmission rates, and death.

CONCLUSION

Largest analysis of post-operative cholangitis following hepatic resection. While a rare occurrence, it is associated with significantly increased risk for severe morbidity and mortality. The most significant risk factors were biliary anastomosis and stenting.

The utility of bile juice culture analysis for the management of postoperative infection after pancreaticoduodenectomy

BACKGROUND

Surgical site infections are common after pancreaticoduodenectomy. Our institution routinely performs intraoperative bile culture with pancreaticoduodenectomy. Herein we examined whether antibiotic selection based on bile culture analysis reduced the surgical site infection risk after pancreaticoduodenectomy.

METHODS

A total of 349 patients underwent pancreaticoduodenectomy with intraoperative bile cultures in our institution between 2008 and 2019. Patients were categorized into "group A" (196 patients who underwent pancreaticoduodenectomy between 2008 and 2013) or "group B" (153 patients who underwent pancreaticoduodenectomy between 2018 and 2019). Group A received cefazoline perioperatively and for 2 days postoperatively, whereas group B received piperacillin-tazobactam instead based on the bile culture findings in group A.

RESULTS

In group A, 91 (46.4%) intraoperative bile cultures were positive, and surgical site infections occurred in 61 patients (31.1%). A total of 32 patients had both positive bile culture and surgical site infection, of whom 23 (71.9%) exhibited the same microorganisms in the biliary and surgical site infection cultures. Due to the common finding of cefazoline-resistant Enterococcus spp. and Enterobacter spp. in group A, group B received piperacillin-tazobactam. Surgical site infection incidence in group B was 18.3% (n = 28), which was significantly lower than in group A (P = .006). Cefazoline-resistant Enterococcus spp. and Enterobacter spp., respectively, were cultured in 69.8% and 24.3% of patients with preoperative biliary drainage, compared with 32.2% and 9.7% of patients without preoperative biliary drainage.

CONCLUSION

The perioperative selection of antibiotics based on bile culture findings at pancreaticoduodenectomy can reduce the incidence of surgical site infection.

Intraoperative gram staining of bile for the prevention of infectious complications in pancreaticoduodenectomy

INTRODUCTION

Infectious complications play a prominent role in pancreaticoduodenectomy. Their incidence increases in cases with preoperative biliary drainage (PBD), due to the higher risk of bacterobilia. The aim of this study is to evaluate an antibiotherapy protocol based on intraoperative gram staining of bile and its impact on postoperative infectious complications.

METHODS

A retrospective study analysing the incidence of infectious complications between two groups of 25 consecutive patients undergoing pancreaticoduodenectomy. In group 1, cefazolin prophylaxis was administered to patients without PBD. In cases with PBD a five days antibiotherapy with piperacillin-tazobactam was administered. In group 2, intraoperative gram staining of bile was routinely performed. If no microorganisms were detected, antibiotherapy was limited to cefazolin prophylaxis. If bacterobilia was detected, targeted antibiotherapy was administered for five days.

RESULTS

The incidence of sepsis and organ/space infection in group 2 was 4% compared to 32% and 24% in group 1 respectively (p < 0.05). No differences were observed in the remaining morbimortality variables. The most prevalent microorganisms in bile were Enterococcus spp. and Klebsiella spp. In postoperative samples, they only appeared in 4% of cases in group 2 (p < 0.05), in favour of S. epidermidis, although they were also prevalent in group 1 (28 and 24% respectively).

CONCLUSION

Intraoperative gram staining of bile fluid could be a useful tool to conduct personalised antibiotic therapy in pancreaticoduodenectomy and contribute to the control of infectious complications.

Cefotaxime resistance in bile samples is an independent predictor of deep infectious complications after pancreaticoduodenectomy in patients with endoprosthesis

BACKGROUND

Bacteriobilia may increase the rate of deep infectious complications (DIC) after pancreaticoduodenectomy. To better adjust prophylactic and empirical antibacterial treatment, we aimed to characterize bacteriobilia in patients with preoperative endoprosthesis, and its association with postoperative DIC.

METHODS

All patients who underwent pancreaticoduodenectomy in our center between 2010 and 2019 were included. The association between microbiological findings from bile samples, and postoperative DIC was analyzed, and we compared microbiology data between 2010-2014 and 2015-2019 periods.

RESULTS

We enrolled 578 patients (median age 67 years [59-72], 58.7% males), of whom 220 (38.1%) had preoperative biliary endoprosthesis, with 197 (89.5%) positive peroperative bile samples pathogens were Enterobacterales, enterococci, and Candida albicans. The incidence of DIC was similar in patients with or without endoprosthesis (20.4% vs. 17.8%, P=0.352). Bacterial isolates collected during 2015-2019 were more resistant to cefotaxime than those recovered from 2010-2014 (45.5% vs. 25.5%, P=0.009). The only independent risk factor for DIC in patients with endoprosthesis was cefotaxime resistance in bile (hazard ratio 3.027 [1.115-8.216], P=0.03).

CONCLUSIONS

The incidence of DIC is high after pancreaticoduodenectomy, with or without endoprosthesis, despite routine postoperative treatment. Cefotaxime resistance, the only independent predictor of DIC in patients with endoprosthesis, has increased over time. Hence, cefotaxime may no longer be an appropriate empirical treatment.

Antibiotic resistance patterns of bacterial bile cultures during pancreatic surgery-a single center analysis and systematic review

BACKGROUND

Septic complications after pancreatic surgery are common. However, it remains unclear if and how a shift of the microbiological spectrum affects morbidity. The aim of the present study was to assess the microbiological spectrum and antibiotic resistance patterns and their impact on outcome.

METHODS

We conducted a retrospective study including patients undergoing pancreatic surgery at our center between 2005 and 2018. A systematic literature review and descriptive meta-analysis of the published and original data was performed according to the PRISMA guidelines.

RESULTS

A total of 318 patients were included in the analysis. Patients with biliary drainage had a significantly higher incidence of bacterobilia (93% vs. 25%) and received preoperative antibiotics (46% vs. 12%). The analyzed bile cultures showed no resistance to piperacillin/tazobactam, fluoroquinolones, or carbapenems. Resistance to cefuroxime was seen in 58% of the samples of patients without biliary drainage (NBD) and 93% of the samples of those with drainage (BD). In general, there was no significant difference in overall postoperative morbidity. However, superficial surgical site infections (SSIs) were significantly more common in the BD group. We included a total of six studies and our own data (1627 patients) in the descriptive meta-analysis. The percentage of positive bile cultures ranged from 53 to 81%. In patients with BD, the most frequent microorganisms were Enterococcus spp. (58%), Klebsiella spp. (29%), and E. coli (27%). Almost all studies demonstrated resistance to first- and second-generation cephalosporins and to third- and fourth-generation cephalosporins for patients with BD.

CONCLUSION

A change in perioperative antibiotic strategy according to local resistance patterns, especially after BD, might be useful for patients undergoing pancreatic surgery. Appropriate perioperative antibiotic coverage may help to prevent abdominal infectious complications and especially superficial SSIs.

Impact of preoperative biliary drainage on 30 Day outcomes of patients undergoing pancreaticoduodenectomy for malignancy

BACKGROUND

Preoperative biliary drainage (PBD) has been advocated to address the plethora of physiologic derangements associated with cholestasis. However, available literature reports mixed outcomes and is based on largely outdated and/or single-institution studies.

METHODS

Patients undergoing PBD prior to pancreaticoduodenectomy (PD) for periampullary malignancy between 2014-2018 were identified in the ACS-NSQIP pancreatectomy dataset. Patients with PBD were propensity-score-matched to those without PBD and 30-day outcomes compared.

RESULTS

8,970 patients met our inclusion criteria. 4,473 with obstruction and PBD were matched to 829 with no preoperative drainage procedure. In the non-jaundiced cohort, 711 stented patients were matched to 2,957 without prior intervention. PBD did not influence 30-day mortality (2.2% versus 2.4%) or major morbidity (19.8% versus 20%) in patients with obstructive jaundice. Superficial surgical site infections (SSIs) were more common with PBD (6.8% versus 9.2%), however, no differences in deep or organ-space SSIs were found. Patients without obstruction prior to PBD exhibited a 3-fold increase in wound dehiscence (0.5% versus 1.5%) additionally to increased superficial SSIs.

CONCLUSION

PBD was not associated with an increase in 30-day mortality or major morbidity but increased superficial SSIs. PBD should be limited to symptomatic, profoundly jaundiced patients or those with a delay prior to PD.

[The effect of preoperative biliary stent on postoperative complications after the resection of pancreatic head tumour]

Introduction. A preoperative biliary stent is often inserted because of obstructive jaundice due to pancreatic head tumour. However, it can also be the source of complications too. Aim and method. We retrospectively analyzed our operations which were performed between 01.10.2017 and 31.12.2019 for pancreatic tumour in association with stent related mortality and morbidity. The multiresistant bacteria and the spectrum of microorganism of intraoperative bile samples were investigated. Results. 82 patients were operated on with pancreatic tumour. There were 63 pancreatic head resections, and 19 palliative operations. 63 pancreatic head resections were analyzed. There were 36 open and 27 laparoscopic operations. Extended operation was needed in 12 cases (5 portal vein resections, 2 splenectomies, 1 right hepatolobectomy, 1 right hemicolectomy, 2 liver metastasectomies and 1 hepatic artery resection). The average age of 36 stented patients of which 24 were men and 12 women were 65 and 64 years respectively. The average age of 27 non-stented patients of which 14 were men and 13 were women, were 67.9 and 58 years respectively. The bile culture proved to be positive 30/36(83%) in the stented group and 13/27(48%) in the non-stented group (P = 0.005). The 3 most common bacteria were E coli, Enterococcus fecalis and Klebsiella pneumoniae in both groups followed by the yeast of Candida. 8 multiresistant bacteria were noticed in the stented group. 6 were ESBL producing (P = 0.033) and 2 vancomycine resistant (P = 0.5) bacteria. 3 patients of the stented group and 2 patients of the non-stented group were lost during the first 30 days. There were 4/0 wound infections, 6/2 haemorrhages, 2/2 pancreatic fistulas, and 2/3 abdominal abscesses in the stented vs. non stented groups. The average length of stay was 19.47 days in the stented and 14.62 days in the non-stented groups (P = 0.14). Conclusion. With regard to the fact that biliary stent changes the bacterial flora it is important to choose the proper antibiotic prophylaxis to reduce morbidity. On the basis of our own results and the literature an effective antibiotic therapy is suggested against enterococcus and ESBL producing bacteria. The prophylaxis against yeast in particularly in immunocompromised cases should also be considered. Regular antibiotic resistance check-up is essential.

[Bacterial hepatobiliary infections : Pathogen spectrum, antimicrobial resistance and current treatment concepts]

Ascending cholangitis and pyogenic liver abscesses are acute febrile bacterial hepatobiliary diseases. Nowadays they frequently occur in patients with structural changes of the biliary system and are usually treated by a combination of interventional drainage procedures and antimicrobial therapy. While Gram-negative Enterobacterales were identified as major causes in the past, biliary tract interventions and antibiotic exposure have contributed to an increase in enterococcal species and extended spectrum beta-lactamase (ESBL)-producing Enterobacterales. When selecting an appropriate empirical treatment the treating internist must consider local and individual risk factors for antimicrobial resistance in addition to pharmacokinetic aspects and disease severity to reduce the likelihood of treatment failure.

The clinical impact of preoperative biliary drainage on isolated infectious complications (iiC) after pancreatic head resection—a retrospective study

Background

The perioperative morbidity after pancreatoduodenectomy (PD) is mostly influenced by intraabdominal complications which are often associated with infections. In patients with preoperative biliary drainage (PBD), the risk for postoperative infections may be even elevated. The aim of this study is to explore if isolated infectious complications without intraabdominal focus (iiC) can be observed after PD and if they are associated to PBD and antibiotic prophylaxis with potential conclusions for their treatment.

Methods

During a 10-year period from 2009 to 2019, all consecutive PD were enrolled prospectively in a database and analyzed retrospectively. Bacteriobilia (BB) and Fungibilia (FB) were examined by intraoperatively acquired smears. A perioperative antibiotic prophylaxis was performed by Ampicillin/Sulbactam. For this study, iiC were defined as postoperative infections like surgical site infection (SSI), pneumonia, unknown origin etc. Statistics were performed by Fisher’s exact test and Mann Whitney U test.

Results

A total of 426 PD were performed at the Vivantes Humboldt-hospital. The morbidity was 56% (n = 238). iiC occurred in 93 patients (22%) and accounted for 38% in the subgroup of patients with postoperative complications. They were not significantly related to BB and PBD but to FB. The subgroup of SSI, however, had a significant relationship to BB and FB with a poly microbial profile and an accumulation of E. faecalis, E. faecium, Enterobacter, and Candida. BB was significantly more frequent in longer lay of PBD. Resistance to standard PAP and co-existing resistance to broad spectrum antibiotics is frequently found in patients with iiC. The clinical severity of iiC was mostly low and non-invasive therapy was adequate. Their treatment led to a significant prolongation of the hospital stay.

Conclusions

iiC are a frequent problem after PD, but only in SSI a significant association to BB and FB can be found in our data. Therefore, the higher resistance of the bacterial species to routine PAP, does not justify broad spectrum prophylaxis. However, the identification of high-risk patients with BB and PBD (length of lay) is recommended. In case of postoperative infections, an early application of broad-spectrum antibiotics and adaption to microbiological findings from intraoperatively smears may be advantageous.

Optimizing Nanopore Sequencing for Rapid Detection of Microbial Species and Antimicrobial Resistance in Patients at Risk of Surgical Site Infections

Surgical site infections (SSI) are a significant burden to patients and health care systems. We evaluated the use of Nanopore sequencing (NS) to rapidly detect microbial species and antimicrobial resistance (AMR) genes present in intraoperative bile aspirates. Bile aspirates from 42 patients undergoing pancreatic head resection were included. Three methods of DNA extraction using mechanical cell lysis or protease cell lysis were compared to determine the optimum method of DNA extraction. The impact of host DNA depletion, sequence run duration, and use of different AMR gene databases was also assessed. To determine clinical value, NS results were compared to standard culture (SC) results. NS identified microbial species in all culture positive samples. Mechanical lysis improved NS detection of cultured species from 60% to 76%, enabled detection of fungal species, and increased AMR predictions. Host DNA depletion improved detection of streptococcal species and AMR correlation with SC. Selection of AMR database influenced the number of AMR hits and resistance profile of 13 antibiotics. AMR prediction using CARD and ResFinder 4.1 correctly predicted 79% and 81% of the bile antibiogram, respectively. Sequence run duration positively correlated with detection of AMR genes. A minimum of 6 h was required to characterize the biliary microbes, resulting in a turnaround time of 14 h. Rapid identification of microbial species and AMR genes can be achieved by NS. NS results correlated with SC, suggesting that NS may be useful in guiding early antimicrobial therapy postsurgery. IMPORTANCE Surgical site infections (SSI) are a significant burden to patients and health care systems. They increase mortality rates, length of hospital stays, and associated health care costs. To reduce the risk of SSI, surgical patients are administered broad-spectrum antibiotics that are later adapted to target microbial species detected at the site of surgical incision. Use of broad-spectrum antibiotics can be harmful to the patient. We wanted to develop a rapid method of detecting microbial species and their antimicrobial resistance phenotypes. We developed a method of detecting microbial species and predicting resistance phenotypes using Nanopore sequencing. Results generated using Nanopore sequencing were similar to current methods of detection but were obtained in a significantly shorter amount of time. This suggests that Nanopore sequencing could be used to tailor antibiotics in surgical patients and reduce use of broad-spectrum antibiotics.

Antibiotic Prophylaxis for Hepato-Biliopancreatic Surgery—A Systematic Review

Background: Surgical site infections (SSIs) are among the most important determinants of morbidity after HBP surgery. Their frequency after HPB surgery is variable, from 1–2% after elective cholecystectomy to 25% after PD. Methods: A systematic review was performed to assess the role of antimicrobial prophylaxis (AP) in HPB elective surgery. Articles published between 2015 and 2021 were obtained; those before 2015 were not included because they antedate the WHO guidelines on SSI prevention. We conducted three different research methods for liver resection, elective cholecystectomy and pancreatic and biliary surgery regarding patients requiring preoperative biliary drainage. Results: Hepatic surgery, improvement in surgical technique and perioperative management lead to a very low SSI. One preoperative 2 g cefazolin dose may be adequate for surgical prophylaxis. From preoperative biliary drainage, we can derive that patients’ homeostasis rather than AP plays a paramount role in reducing postoperative morbidity. The time from biliary drainage could be an essential element in decision making for surgical prophylaxis. In the case of low-risk cholecystectomy, it is not easy to draw definitive conclusions about the effect of AP. Data from the literature are inconsistent, and some risk factors cannot be predicted before surgery. Conclusion: in our opinion, a strict preoperative cefazolin dose strategy can be reasonable in HBP surgery until a large-scale, multicentric RCT brings definitive conclusions.

The Role of Targeted Versus Standard Antibiotic Prophylaxis in Pancreatoduodenectomy in Reducing Postoperative Infectious Complications: A Systematic Review and Meta-analysis

INTRODUCTION

Infectious complications are common after pancreatoduodenectomy, which in turn are associated with preoperative biliary drainage. Current guidelines recommend a first-generation cephalosporin as perioperative antibiotic prophylaxis. However, some studies support the use of targeted antibiotics. The aim of this systematic review and meta-analysis is to evaluate the role of prophylactic targeted antibiotics compared to standard antibiotics in reducing postoperative infections after pancreatoduodenectomy.

METHODS

A search from MEDLINE, EMBASE, and Cochrane library from 1946 to July 2020 was conducted. Studies were included if they compared targeted antibiotics with standard perioperative antibiotics while including outcome data on surgical site infections (SSI). Targeted therapy was defined as perioperative antibiotics targeting organisms prevalent in bile instrumentation or by culture data obtained from the patient or institution. Outcomes assessed were the rate of SSIs and their microbiology profile. Analyses included demographic data, perioperative antibiotics, postoperative outcomes including microbiology data, and meta-analysis was performed where applicable.

RESULTS

Seven studies were included, with a total of 849 patients undergoing pancreatoduodenectomy. Targeted antibiotics were associated with a significantly lower rate of postoperative SSI compared to standard antibiotic therapy [21.1% vs 41.9%; risk ratios (RR) 0.55, 95% confidence interval 0.37-0.81]. Wound/incisional site infections and organ space infections were lower in patients receiving targeted antibiotic prophylaxis (RR 0.33, P = 0.0002 and RR 0.54, P = 0.0004, respectively). Enterococcus species were the most common bacteria reported.

CONCLUSION

There was a significant reduction in overall SSI rates when targeted antibiotics was used. Current standard antibiotic prophylaxis is inadequate in covering microbes prevalent in postoperative infections developing after pancreatoduodenectomy.

Intraoperative Bile Culture in Pancreaticoduodenectomy: Teaching Old Dogma New Tricks

INTRODUCTION

Biliary stents increase surgical site infections (SSIs) following pancreaticoduodenectomy due to bactibilia and contaminated intraoperative bile spillage. Intraoperative bile culture (IOBC) is performed to guide empiric therapy for SSIs; however, its utility is poorly studied. We sought to evaluate IOBC and the interplay between stenting, bactibilia, and SSI following pancreaticoduodenectomy.

METHODS

Patients undergoing pancreaticoduodenectomy from January 2008 to April 2020 were identified through our institutional National Surgical Quality Improvement Project (NSQIP) database; patients without IOBC were excluded. Odds of SSI were analyzed with multivariable logistic regression.

RESULTS

Four-hundred-eighty-three patients were identified. One-hundred-eighty-nine (39%) patients had plastic stents and 154 (32%) had metal stents. Three-hundred-twenty-nine (96%) patients with stents had bactibilia versus 18 (13%) without stents (P < 0.001). The biliary microbiome and antibiotic resistance patterns in patients with metal and plastic stents were nearly identical. Of 159 NSQIP-defined SSIs, most were incisional (n = 92, 58%). Bactibilia and stent presence were associated with incisional (OR 3.69 and 3.39, both P < 0.001) but not organ space SSI (P > 0.1); however, stent type was not (P > 0.5). Of the 73 speciated SSI cultures, an IOBC-identified organism was present in 42 (58%), while at least one organism not found in the IOBC was present in 49 (67%).

CONCLUSION

Bactibilia is associated with incisional but not organ space SSI following pancreaticoduodenectomy and is strongly associated with stent presence. Stent type does not independently influence the biliary microbiome or SSI risk. IOBC has a poor ability to predict causative organisms in SSIs following pancreaticoduodenectomy and is not recommended for routine use.

"Answers in hours": A prospective clinical study using nanopore sequencing for bile duct cultures

BACKGROUND

Surgical site infection is a major source of morbidity in patients undergoing pancreatic head resection and is often from organisms in intraoperative bile duct cultures. As such, many institutions use prolonged prophylactic antibiotics and tailor based on bile duct cultures. However, standard cultures take days, leaving many patients unnecessarily on prolonged antibiotics. Nanopore sequencing can provide data in hours and, thus, has the potential to improve antibiotic stewardship. The present study investigates the feasibility of nanopore sequencing in intraoperative bile samples.

METHODS

Patients undergoing pancreatic head resection were included. Intra-operative bile microbial profiles were determined with standard cultures and nanopore sequencing. Antibiotic recommendations were generated, and time-to-results determined for both methods. Organism yields, resistance patterns, antibiotic recommendations, and costs were compared.

RESULTS

Out of 42 patients, 22 (52%) had samples resulting in positive standard cultures. All positive standard cultures had microbes detected using nanopore sequencing. All 20 patients with negative standard cultures had negative nanopore sequencing. Nanopore sequencing detected more bacterial species compared to standard cultures (10.5 vs 4.4, p < 0.05) and more resistance genotypes (10.3 vs 2.7, p < 0.05). Antimicrobial recommendations based on nanopore sequencing provided coverage for standard cultures in 27 out of 44 (61%) samples, with broader coverage recommended by nanopore sequencing in 13 out of 27 (48%) of these samples. Nanopore sequencing results were faster (8 vs 98 hours) than standard cultures but had higher associated costs ($165 vs $38.49).

CONCLUSION

Rapid microbial profiling with nanopore sequencing is feasible with broader organism and resistance profiling compared to standard cultures. Nanopore sequencing has perfect negative predictive value and can potentially improve antibiotic stewardship; thus, a randomized control trial is under development.

Rising Incidence of Peri-Operative Bactibilia among Patients Undergoing Complex Biliopancreatic Surgery

Background: Biliary instrumentation is associated with bactibilia and post-operative infection. Bactibilia incidence over time remains unknown. Patients and Methods: Consecutive patients with bilioenteric anastomosis surgery and available surveillance intra-operative bile duct cultures were evaluated for post-operative infection. The study period (2008-2019) was divided into quartiles to examine time-based trends. Results: Among 101 cases, 60 intra-operative bile duct cultures had no growth and 41 patients had documented at least one culture-positive isolate in their bile. Frequency of patients with culture-positive intra-operative bile increased over the study period (period 1, 1/28, 3.6% vs. period 2, 7/21, 33.3% vs. period 3, 15/26, 57.7% vs. period 4, 18/26, 69.2%; p < 0.001). Culture-positive post-operative infection (17/101; 16.8%) was not associated with intra-operative bile duct culture (p = 0.552), however, the same micro-organism isolate was identified on post-operative infection and intra-operative culture of bile duct bile among six of 17 patients (35.3%). Conclusions: We found an increasing incidence of bactibilia and post-operative culture-positive infections over the last decade. One-third of patients with a positive intra-operative bile duct culture experienced post-operative infection with the same organism, yet a clear link between bile colonization and post-operative infection was not established.

Intraoperative gram staining of bile for the prevention of infectious complications in pancreaticoduodenectomy

INTRODUCTION

Infectious complications play a prominent role in pancreaticoduodenectomy. Their incidence increases in cases with preoperative biliary drainage (PBD), due to the higher risk of bacterobilia. The aim of this study is to evaluate an antibiotherapy protocol based on intraoperative gram staining of bile and its impact on postoperative infectious complications.

METHODS

A retrospective study analysing the incidence of infectious complications between two groups of 25 consecutive patients undergoing pancreaticoduodenectomy. In group 1, cefazolin prophylaxis was administered to patients without PBD. In cases with PBD a five days antibiotherapy with piperacillin-tazobactam was administered. In group 2, intraoperative gram staining of bile was routinely performed. If no microorganisms were detected, antibiotherapy was limited to cefazolin prophylaxis. If bacterobilia was detected, targeted antibiotherapy was administered for five days.

RESULTS

The incidence of sepsis and organ/space infection in group 2 was 4% compared to 32% and 24% in group 1 respectively (p<0.05). No differences were observed in the remaining morbimortality variables. The most prevalent microorganisms in bile were Enterococcus spp and Klebsiella spp. In postoperative samples, they only appeared in 4% of cases in group 2 (p<0.05), in favour of S. epidermidis, although they were also prevalent in group 1 (28 and 24% respectively).

CONCLUSION

Intraoperative gram staining of bile fluid could be a useful tool to conduct personalised antibiotic therapy in pancreaticoduodenectomy and contribute to the control of infectious complications.

Different Biliary Microbial Flora Influence Type of Complications after Pancreaticoduodenectomy: A Single Center Retrospective Analysis

BACKGROUND

Bacterobilia is associated with postoperative morbidity after pancreaticoduodenectomy (PD), mostly due to infectious complications. The aim of this study was to investigate the prevalence of bacteria species isolated from intraoperative biliary cultures, and related complications after PD.

METHODS

An ANOVA test was used to assess the prevalence of isolated bacterial species and postoperative complications. The odds ratio was computed to evaluate the association between biliary cultures and each complication, Endoscopic Retrograde CholangioPancreatography (ERCP) and each complication, ERCP and biliary cultures, Delayed Gastric Emptying (DGE) and Postoperative Pancreatic Fistula (POPF).

RESULTS

Positive biliary cultures were found in 162/244 (66%) PDs. Different prevalences of polymicrobial biliary culture were detected in patients with postoperative complications. In SSIs, a significant prevalence of biliary culture positive for E. coli, Klebsiella pneumoniæ and Enterococcus fæcalis (p < 0.001) was detected. Prevalences of polymicrobial biliary cultures with Escherichia coli, Klebsiella pneumoniæ, Enterococcus fæcalis and Enterococcus fæcium were significantly associated with POPF (p < 0.001). Biliary culture positive for Escherichia coli, Enterococcus fæcalis and Enterococcus fæcium showed a higher prevalence of intra-abdominal collection and DGE (p < 0.001). Notably, Escherichia coli was significantly associated with DGE as a unique complication (OR = 2.94 (1.30-6.70); p < 0.01).

CONCLUSIONS

Specific prevalences of polymicrobial bacterobilia are associated with major complications, while monomicrobial Escherichia coli bacterobilia is associated with DGE as a unique complication after PD.

Microbiome Patterns in Matched Bile, Duodenal, Pancreatic Tumor Tissue, Drainage, and Stool Samples: Association with Preoperative Stenting and Postoperative Pancreatic Fistula Development

Postoperative complications after pancreatic surgery are still a significant problem in clinical practice. The aim of this study was to characterize and compare the microbiomes of different body compartments (bile duct, duodenal mucosa, pancreatic tumor lesion, postoperative drainage fluid, and stool samples; preoperative and postoperative) in patients undergoing pancreatic surgery for suspected pancreatic cancer, and their association with relevant clinical factors (stent placement, pancreatic fistula, and gland texture). For this, solid (duodenal mucosa, pancreatic tumor tissue, stool) and liquid (bile, drainage fluid) biopsy samples of 10 patients were analyzed using 16s rRNA gene next-generation sequencing. Our analysis revealed: (i) a distinct microbiome in the different compartments, (ii) markedly higher abundance of Enterococcus in patients undergoing preoperative stent placement in the common bile duct, (iii) significant differences in the beta diversity between patients who developed a postoperative pancreatic fistula (POPF B/C), (iv) patients with POPF B/C were more likely to have bacteria belonging to the genus Enterococcus, and (v) differences in microbiome composition with regard to the pancreatic gland texture. The structure of the microbiome is distinctive in different compartments, and can be associated with the development of a postoperative pancreatic fistula.

Perioperative Broad-spectrum Antibiotics are Associated With Decreased Surgical Site Infections Compared to 1st–3rd Generation Cephalosporins After Open Pancreaticoduodenectomy in Patients With Jaundice or a Biliary Stent

OBJECTIVE

Compare the effectiveness of 1st-3rd generation cephalosporins (1st-3rdCE) to broad-spectrum antibiotics in decreasing surgical site infections (SSI) after pancreatectomy.

SUMMARY OF BACKGROUND DATA

SSI is one of the most common complications after pancreatic surgery. Various antibiotic regimens are utilized nationwide with no clear guidelines for pancreatectomy. As we await results of a recently initiated prospective trial, this study retrospectively evaluates over 15,000 patients using the same administrative data abstraction tools as in the trial.

METHODS

All relevant clinical variables were collected from the 2016-2018 targeted-pancreatectomy database from the American College of Surgeon National Surgical Quality Improvement Program. Preoperative antibiotics were initially collected as first-generation cephalosporin, second or third-generation cephalosporin, and broad-spectrum antibiotics (Broad-abx).

RESULTS

Of the 15,182 patients who completed a pancreatic surgery between 2016 and 2018, 6114 (40%) received a first-generation cephalosporin, 4097 (27%) received a second or third-generation cephalosporin, and 4971 (33%) received Broad-abx. On multivariate analysis, Broad-abx was associated with a decrease in all-type SSI compared to 1st-3rdCE (odds ratio = 0.73-0.77, P < 0.001) after open pancreaticoduodenectomy (PD). There was no difference in SSI between antibiotic-types after distal pancreatectomy. Subgroup multivariate analysis of open PD revealed decrease in all-type SSI with Broad-abx amongst patients with jaundice and/or biliary stent only, regardless of wound protector use (odds ratio = 0.69-0.70, P < 0.001). Propensity score matching of open PD patients with jaundice and/or biliary stent confirmed a decrease in all-type SSI (19% vs 24%, P = 0.001), and organ-space SSI (12% vs 16%, P < 0.001).

CONCLUSION

Broad-abx are associated with decreased SSI after open PD and may be preferred specifically for patients with preoperative biliary stent and/ or jaundice.