Increased plasma levels of IL-6 and IL-8 are associated with surgical site infection after pancreaticoduodenectomy

Adjuvant chemotherapy omission after pancreatic cancer resection: a French nationwide study

BACKGROUND

Adjuvant chemotherapy (AC) improves the prognosis after pancreatic ductal adenocarcinoma (PDAC) resection. However, previous studies have shown that a large proportion of patients do not receive or complete AC. This national study examined the risk factors for the omission or interruption of AC.

METHODS

Data of all patients who underwent pancreatic surgery for PDAC in France between January 2012 and December 2017 were extracted from the French National Administrative Database. We considered "omission of adjuvant chemotherapy" (OAC) all patients who failed to receive any course of gemcitabine within 12 postoperative weeks and "interruption of AC" (IAC) was defined as less than 18 courses of AC.

RESULTS

A total of 11 599 patients were included in this study. Pancreaticoduodenectomy was the most common procedure (76.3%), and 31% of the patients experienced major postoperative complications. OACs and IACs affected 42% and 68% of the patients, respectively. Ultimately, only 18.6% of the cohort completed AC. Patients who underwent surgery in a high-volume centers were less affected by postoperative complications, with no impact on the likelihood of receiving AC. Multivariate analysis showed that age ≥ 80 years, Charlson comorbidity index (CCI) ≥ 4, and major complications were associated with OAC (OR = 2.19; CI95%[1.79-2.68]; OR = 1.75; CI95%[1.41-2.18] and OR = 2.37; CI95%[2.15-2.62] respectively). Moreover, age ≥ 80 years and CCI 2-3 or ≥ 4 were also independent risk factors for IAC (OR = 1.54, CI95%[1.1-2.15]; OR = 1.43, CI95%[1.21-1.68]; OR = 1.47, CI95%[1.02-2.12], respectively).

CONCLUSION

Sequence surgery followed by chemotherapy is associated with a high dropout rate, especially in octogenarian and comorbid patients.

Serum Interleukin-6 as a Biomarker for Early Prediction of Post-Operative Infectious Complications After Elective Pancreatectomy

Background: To investigate whether interleukin (IL)-6 could predict the post-operative complications of elective pancreatectomy early. Patients and Methods: Overall, 122 patients who underwent elective pancreatectomy from June 2020 to May 2021 in our hospital were enrolled. Interleukin-6 was measured on the day before and at six hours after surgery, and on post-operative day one, three, and five. The associations between IL-6 level and post-operative complications were analyzed, and the predictive value of IL-6 for complications was assessed. Results: Sixty-three patients developed post-operative complications. Higher IL-6 was observed in patients with post-operative complications on post-operative day one, post-operative day three, and post-operative day five, with odd ratios of 1.43, 1.68, and 2.54 (p = 0.01, p = 0.01, and p = 0.01), respectively. These trends were also observed in patients with infectious complications preoperatively, on post-operative day one, post-operative day three, and post-operative day five, with ORs of 2.46, 1.95, 2.01, and 2.49 (p = 0.00, 0.00, 0.01, 0.00) respectively. Multivariate regression revealed that IL-6 is the only predictor for infectious complications on post-operative day one (p = 0.016). Based on the optimal cutoffs, pre-operative IL-6, IL-6 on post-operative day one and post-operative day three for predicting infectious complications yielded area under the curve (AUC) of 0.73, 0.70, and 0.70, with high negative predictive value of 82.7%, 92.2%, and of 91.3%, respectively. Conclusions: This study validated the early predictive value of IL-6 on infectious complications after pancreatectomy. Because of the performance of serum IL-6 in predicting infectious complications and high NPV, we endorse that IL-6 could be a potential biomarker for early prediction and antibiotic optimization after pancreatectomy.

Derivation and validation of a novel preoperative risk prediction model for surgical site infection in pancreaticoduodenectomy and comparison of preoperative antibiotics with different risk stratifications in retrospective cohort

BACKGROUND

Surgical site infections (SSIs) are common postoperative complications of pancreaticoduodenectomy.

AIM

To develop a model for preoperative identification of the risk of SSI that may improve outcomes and guide preoperative antibiotics.

METHODS

The prediction model was built by meta-analysis. After literature search and inclusion, data extraction, and quantitative synthesis, the prediction model was established based on the pooled odds ratio of predictors. A single-centre retrospective cohort was the validation cohort. Receiver operating characteristic curves and area under the curve were used to assess the model's ability. We also created a decision curve and a calibration plot to assess the nomogram. The effects of prophylactic antibiotics on SSI were compared between groups by multivariable logistic regression with different risk stratifications.

FINDINGS

Twenty-eight studies were included in the meta-analysis, 17 studies in the derivation cohort. Age, male gender, body mass index, pancreatic duct diameter, high-risk diagnosis, and preoperative biliary drainage were selected to build the prediction model. The model was validated in an external cohort. The cut-off value was 3.5 and area under the curve (AUC) was 0.76 in open pancreaticoduodenectomy (OPD). In laparoscopic pancreaticoduodenectomy, the cut-off value was 4.5 and AUC was 0.69. Decision curve and calibration plot showed good usability of the model, especially in OPD. Multivariable logistic regression did not indicate differences between broad- and narrow-spectrum antibiotics for SSI in different risk stratifications.

CONCLUSION

The model can identify patients with a high risk of SSI preoperatively. The choice of prophylactic antibiotics under different risk stratifications should be investigated further.

Association between Serum Biomarkers with Postoperative Complications and Delay of Adjuvant Chemotherapy Initiation in Ovarian Cancer Patients Undergoing Primary Cytoreductive Surgery: A Pilot Study

This study sought to describe and relate the factors associated with complications and delays in adjuvant chemotherapy in patients with ovarian cancer treated with primary cytoreductive surgery. Serum from patients diagnosed with ovarian cancer scheduled for primary cytoreductive surgery were analyzed for prealbumin, 25-OH Vitamin D, intracellular adhesion molecule 1 (ICAM-1), interleukin 6 (IL-6), interleukin 8 (IL-8), monocyte chemoattractant protein 1 (MCP-1), monocyte chemoattractant protein 2 (MCP-2), macrophage derived chemokine (MDC). Postoperative complications were identified using common terminology criteria for adverse events 4.0 and 30 day after surgery. Delays in adjuvant chemotherapy were defined as >1 week interval between surgery and initiation. Patients with postoperative complications (39.6%) were significantly older, had lower serum prealbumin levels, and higher serum IL-6 and IL-8 than those without. Univariate logistic regression found that age (OR: 1.12, 95%CI: 1.00-1.35) and IL-6 (OR: 1.02, 95%CI: 0.99-1.05) were associated with postoperative complications, whereas age remained significant after multivariate analysis (OR:1.14, 95%CI: 1.00-1.29). Patients with delays in chemotherapy exhibited greater BMI and lower 25-OH Vitamin D than those without. Multivariate analysis found that increasing levels of 25-OH Vitamin D were associated with a lower risk of delayed chemotherapy initiation after controlling for age, body mass index, and tumor grade (OR: 0.93, 95%CI:0.87-0.99). This work suggests that in addition to age being predictive of postoperative complications, serum 25-OH Vitamin D may a provide insight into a patient's risk for postsurgical delays in chemotherapy initiation. These findings should, however, be confirmed in a larger study including robust survival analysis.

Geriatric nutritional risk index serves as risk factor of surgical site infection after pancreatoduodenectomy: a validation cohort Ageo study

Background

Surgical site infections (SSIs), which are associated with preoperative malnutrition, are a well-known potential complication of surgery that leads to increased medical costs and longer hospitalizations. Thus, surgeons need to accurately identify patients at high-risk for SSIs. Considering that the Geriatric Nutritional Risk Index (GNRI) was designed to assess the degree of malnutrition specifically among elderly patients, previous evidence (Kawaguchi study) proved that GNRI predicted the risk of SSIs in patients following pancreatoduodenectomy (PD). In this study, we aimed to validate whether that the same index could predict the risk of SSI among patients who underwent PD in our patient cohort (Ageo study).

Methods

The current validation cohort study was retrospectively conducted on 93 patients at the Department of Surgery, Ageo Central General Hospital, Japan, from January 2015 to October 2019. All patients were subjected to nutritional screening using the GNRI and were followed up for the occurrence of postoperative complications. Additionally, risk factors for developing SSI, as well as patient's height, body mass index, and preoperative laboratory values, were recorded.

Results

Patients were divided into the SSI (N=30) and non-SSI (N=63) groups with a determined SSI incidence rate of 32.3% (30/93). The SSI group had significantly lower GNRI than the non-SSI group (P<0.001). Receiver operating characteristic curve analysis determined a cutoff GNRI value of 94 (sensitivity, 83.3%; specificity, 83.6%), similar to that in the previous study. Univariate and multivariate analyses confirmed that a GNRI of <94 was significantly associated with SSI (P<0.001).

Conclusions

The present Ageo study confirmed the consistency of results in Kawaguchi study. Thus, lower GNRI can be a universal marker for SSI risk following PD.

No Significant Effect of Daikenchuto (TJ-100) on Peritoneal IL-9 and IFN-γ Levels After Pancreaticoduodenectomy

Aim and Background

TJ-100 is a traditional Japanese medicine that affects inflammation and gastrointestinal motility, and is used as a preventive and treatment for paralytic ileus. This study aims at determining the effect of TJ-100 on the peritoneal levels of IFN-γ/IL-9, cytokines related to ileus, after pancreaticoduodenectomy (PD) in a clinical setting.

Methods

This was a subsidiary study of the clinical trial investigating the effect of TJ-100 on postoperative bowel function. Ascites was collected from 180 patients using an abdominal drainage tube on postoperative day 1 and 3 after PD (POD 1 or POD 3) and used to measure 27 cytokines. We performed univariate and multivariate analyses using several perioperative variables and administration of TJ-100/placebo to determine the effect of TJ-100 on the levels of IFN-γ and IL-9.

Results

Peritoneal levels of IL-9 and IFN-γ decreased between POD 1 and 3 (Wilcoxon signed-rank test p<0.001). Multivariate analysis was performed after univariate analysis to select the variables and patients with a body mass index of ≥22 kg/m², older age, use of epidural anesthesia, and longer surgery correlated with the levels of IL-9 and IFN-γ. However, we could not detect a correlation between the use of TJ-100 and cytokine levels in ascites either on POD 1 or 3.

Conclusion

TJ-100 did not affect peritoneal IL-9 and IFN-γ levels after PD. This was in accordance with published clinical findings showing no improvement in bowel function after PD and TJ-100 treatment.

The association between the inflammatory response to surgery and postoperative complications in older patients with cancer; a prospective prognostic factor study

BACKGROUND

Accurate prognostic biomarkers would substantially improve surgical planning and decisions making yet no studies have been reported exploring the inflammatory response in surgically treated older patients with cancer. The aim of this study was to explore inflammatory biomarkers as potential prognostic factors for postoperative complications within 30 days in older patients with cancer.

METHOD

Patients 65 years and older undergoing surgery for removal of a solid malignant tumour were included in an observational cohort study. All complications occurring up to 30 days postoperatively were documented prospectively. Inflammatory markers were measured in plasma samples pre- and postoperatively: C-reactive protein (CRP), Interleukin-1 beta (IL-1β), IL-6, IL-10, IL-12, and Tumour necrosis factor-alpha (TNF-α). Associations between inflammatory markers and postoperative complications were explored using logistic regression analysis.

RESULTS

Between July 2010 and April 2014, plasma samples of 224 patients were collected. Median age was 72 (65-89) years and 116 (51.8%) patients were female. Approximately half of the patients developed postoperative complications (49.6%) of whom 62 patients (55.9%) developed >1 complication. An independent prognostic effect was observed for the inflammatory biomarkers IL-6 and IL-10 for the occurrence of postoperative complications.

CONCLUSION

The perioperative inflammatory response is associated with complications, independently from patient and surgical factors which are also associated with outcome. Research is warranted towards further exploration of the perioperative inflammatory response with the aim to improve perioperative care and outcome, and might help to improve surgical planning and decision making for older patients with cancer.

Distinct Chemokine Dynamics in Early Postoperative Period after Open and Robotic Colorectal Surgery

Stress response to robot-assisted colorectal surgery is largely unknown. Therefore, we conducted a prospective comparative nonrandomized study evaluating the perioperative dynamics of chemokines: IL-8/CXCL8, MCP-1/CCL2, MIP-1α/CCL3, MIP-1β/CCL4, RANTES/CCL5, and eotaxin-1/CCL11 in 61 colorectal cancer patients following open colorectal surgery (OCS) or robot-assisted surgery (RACS) in reference to clinical data. Postoperative IL-8 and MCP-1 increase was reduced in RACS with a magnitude of blood loss, length of surgery, and concomitant up-regulation of IL-6 and TNFα as its independent predictors. RANTES at 8 h dropped in RACS and RANTES, and MIP1α/β at 24 h were more elevated in RACS than OCS. IL-8 and MCP-1 at 72 h remained higher in patients subsequently developing surgical site infections, in whom a 2.6- and 2.5-fold increase was observed. IL-8 up-regulation at 24 h in patients undergoing open procedure was predictive of anastomotic leak (AL; 94% accuracy). Changes in MCP-1 and RANTES were predictive of delayed restoration of bowel function. Chemokines behave differently depending on procedure. A robot-assisted approach may be beneficial in terms of chemokine dynamics by favoring Th1 immunity and attenuated angiogenic potential and postoperative ileus. Monitoring chemokine dynamics may prove useful for predicting adverse clinical events. Attenuated chemokine up-regulation results from less severe blood loss and diminished inflammatory response.

Clinical significance of drain fluid culture after pancreaticoduodenectomy

BACKGROUND

The mechanism of infected postoperative pancreatic fistula (POPF) following pancreaticoduodenectomy (PD) is undefined. Drain amylase has been used to predict POPF, whereas little data are available about the value of drain fluid culture. The aim was to investigate the incidence, risk factors and association with surgical outcomes of positive drainage culture (PDC) after PD.

METHODS

A single-center retrospective analysis was conducted of prospectively collected data from patients who underwent PD between January 2005 and December 2015. Drain fluid samples were obtained for microbiological analysis after surgery. Risk factors for PDC were evaluated, and its influence on surgical outcomes was explored.

RESULTS

Of 768 patients, 261 (34%) had PDC during the postoperative period. Among them, a total of 434 isolates were yielded. One hundred and seven (24.7%) were Gram-positive, 283 (65.2%) Gram-negative, and 44 (10.1%) fungi. Multivariate analysis revealed that body mass index (BMI) ≥25 kg/m² , preoperative chemoradiation and intra-operative red blood cell transfusion were independent risk factors for PDC. PDC was associated with higher incidences of complications including POPF, major complications and reoperation, but with no correlation between the day of PDC and complications. BMI ≥25 kg/m² , early PDC (≤3 days), main pancreatic duct <3 mm, and soft pancreas were revealed as independent predictors for POPF. There was a correlation between type of microorganisms and complications.

CONCLUSION

Considering the correlation between PDC and postoperative complications, preventive measures are crucial to improve outcomes after PD. Whether antibiotic treatment for early PDC will alter the clinical course of POPF needs further evaluation.

Perioperative antimicrobial therapy in preventing infectious complications following pancreatoduodenectomy

Background & objectives:

Infectious complications have been reported to occur in up to 45 per cent of patients, following pancreatoduodenectomy (PD). The incidence of perioperative infectious and overall complications is higher in patients undergoing preoperative invasive endoscopic procedures. The aim of the study was to compare the role of a carbapenem administered as three-once daily perioperative doses on infectious complications in patients at high risk for these complications versus those at low risk.

Methods:

A retrospective study with some secondary data collected from records was carried out on the data from a prospectively maintained surgical database of patients undergoing PD for pancreatic and periampullary lesions at a tertiary referral care centre, between June 2011 and May 2013. Patients were divided into two groups for comparison based on whether they underwent at least one preoperative endoscopic interventional procedure before PD (high-risk - intervention and low-risk - no intervention). All patients were administered three-once daily doses of ertapenem (1 g).

Results:

A total of 135 patients in two groups were comparable in terms of demographic and nutritional, surgical and histopathological factors. No significant difference between the two groups in terms of the overall morbidity (38.7 vs 35.7%), infectious complications (9.7 vs 4.8%), mortality (2.2 vs 2.4%) and mean post-operative hospital stay (9.2 vs 8.9 days) was observed.

Interpretation & conclusions:

Perioperative three-day course of once-daily administered ertapenem resulted in a non-significant difference in infectious and overall complications in high-risk patients undergoing PD as compared to the low-risk group.

The Significance of Interleukin-6 in the Early Detection of Surgical Site Infections after Definitive Operation for Gastrointestinal Fistulae

BACKGROUND

Surgical site infections (SSIs) are among the most common complications after definitive treatment for intestinal fistulae. Serum inflammatory markers including white blood cell count (WBC), C-reactive protein (CRP), interleukin-6 (IL-6), as well as procalcitonin (PCT) have been used to help diagnosis post-operative complications.

OBJECTIVE

The goal of this study was to assess the clinical value of inflammatory markers, specifically IL-6, in predicting SSIs after intestinal fistulae resection.

METHODS

A total of 184 consecutive patients who underwent elective intestinal fistula resection were enrolled prospectively. All patients were screened to exclude patients with existing clinical infection. Plasma IL-6 concentrations, serum PCT, and CRP concentrations were measured pre-operatively and on post-operative days one, three, and seven. The predictive value of each laboratory marker for SSI was calculated.

RESULTS

The incidence of SSI after elective intestinal fistula resection was 26.7%. Interleukin-6, PCT, and CRP concentrations were higher in patients with SSIs compared with patients without. In contrast, there was no statistical difference for WBC counts between the two groups. Receiver operating characteristic curves demonstrated that IL-6 had the highest diagnostic effectiveness for post-operative SSI on post-operative day one, with an area under the curve of 0.77, and a sensitivity of 85.7% and specificity of 63.9%.

CONCLUSION

A concentration of IL-6 above 95.6 ng/L on post-operative day one and 52.5 ng/L on post-operative day three, and a concentration of PCT exceeding 0.61 mcg/L predict the occurrence of SSI after definitive operations for gastrointestinal fistulae.

Measurement of the inflammatory response in the early postoperative period after hip and knee arthroplasty

BACKGROUND

The aim of this study was to identify an inflammatory marker with fast and predictable kinetics to enable future discrimination between normal postoperative inflammation and potential infection after total hip and knee arthroplasty cases.

METHODS

Changes in serum levels of C-reactive protein (CRP), interleukins (IL) 1β, 6 and 8 and NT-proCNP peptide were measured before and during first 5 postoperative days in 100 patients undergoing total hip or knee arthroplasty. We also compared two methods to describe the magnitude of inflammation--applying separate two sample tests at each time point, and summary measures--area under the curve (AUC).

RESULTS

IL-6 showed a similar kinetics pattern to the CRP in response to surgical trauma. Significantly greater level changes in all markers but NT-proCNP were observed in knee patients. Persisting high levels of CRP, but not other markers, were observed in obese hip patients. IL-6 was found to be an adjunct to routine CRP use.

CONCLUSIONS

IL-6 has faster kinetics and is less influenced by patient weight, therefore it seems to be more useful in clinical practice. Summary measures describe the inflammatory response well and are easier to analyze than multiple analyses of single time points.

Impact of bacterial contamination of the abdominal cavity during pancreaticoduodenectomy on surgical-site infection

Background

Several risk factors for complications after pancreaticoduodenectomy have been reported. However, the impact of intraoperative bacterial contamination on surgical outcome after pancreaticoduodenectomy has not been examined in depth.

Methods

This retrospective study included patients who underwent pancreaticoduodenectomy and peritoneal lavage using 7000 ml saline between July 2012 and May 2014. The lavage fluid was subjected to bacterial culture examination. The influence of a positive bacterial culture on surgical-site infection (SSI) and postoperative course was evaluated. Risk factors for positive bacterial cultures were also evaluated.

Results

Forty-six (21·1 per cent) of 218 enrolled patients had a positive bacterial culture of the lavage fluid. Incisional SSI developed in 26 (57 per cent) of these 46 patients and in 13 (7·6 per cent) of 172 patients with a negative lavage culture (P &lt; 0·001). Organ/space SSI developed in 32 patients with a positive lavage culture (70 per cent) and in 43 of those with a negative culture (25·0 per cent) (P &lt; 0·001). Grade B/C pancreatic fistula was observed in 22 (48 per cent) and 48 (27·9 per cent) respectively of patients with positive and negative lavage cultures (P = 0·010). Postoperative hospital stay was longer in patients with a positive lavage culture (28 days versus 21 days in patients with a negative culture; P = 0·028). Multivariable analysis revealed that internal biliary drainage, combined colectomy and a longer duration of surgery were significant risk factors for positive bacterial culture of the lavage fluid.

Conclusion

Intraoperative bacterial contamination has an adverse impact on the development of SSI and grade B/C pancreatic fistula following pancreaticoduodenectomy.

Nosocomial Infections and Microbiologic Spectrum after Major Elective Surgery of the Pancreas, Liver, Stomach, and Esophagus

BACKGROUND

The majority of infections treated by surgeons are nosocomial infections (NI). The frequency of these infections in relation to the organ operated on as well as the organisms involved are not well defined. Detailed knowledge of these issues is essential for optimal care of surgical patients. This study aimed to determine infection rates and the responsible pathogens after major elective surgery of the pancreas, liver, stomach, and esophagus.

METHODS

Between January 1, 2005 and August 31, 2007, the records of all patients of the Department of General, Abdominal and Vascular Surgery, University Hospital Magdeburg (Germany) with elective resection of the pancreas, liver, stomach, and esophagus were evaluated retrospectively. Study parameters were: Patient number, age, gender, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, indication for resection, operation duration, length of stay (LOS) in the intensive care unit (ICU) and in hospital, mortality, organ-related rate and kind of NI, and microbiologic spectrum. Nosocomial infections were defined as: Surgical site infection (U.S. Centers for Disease Control and Prevention [CDC] 1 or 2) and intra-abdominal infection (CDC 3), urinary tract infection, clinical sepsis, blood stream and catheter-related infection, respiratory tract infection, and pneumonia.

RESULTS

A total of 358 patients were included: 150 (42%) with pancreas resection, 91 (25%) with liver resection, 105 (29%) with gastric resection, and 12 (3%) with esophagus resection. Median LOS in the ICU for all groups was 48.8 h (interquartile range [IQR] 24.9-91.8 h), median LOS in hospital was 16 d (IQR 13-23 d), and in-hospital mortality was 4.5%. Patients with NI had significantly greater in-hospital death and prolonged stay in hospital and ICU (p<0.001). In 120 (33.5%) patients, one or more NI occurred (range, 83% in esophagus patients to 21% in liver patients). Intra-abdominal (16.5%) and surgical site infections (12.3%) were most frequent; 80.8% of the NI were culture-positive. The most frequent clinically relevant isolates were Escherichia coli (12.4%), coagulase-negative staphylococci (CoNS) (12.2%), and Enterococcus faecium (9.7%). The highest resistance rates were found for Staphylococcus aureus (methicillin-resistant S. aureus [MRSA] 29.4%) and Pseudomonas aeruginosa (23.5%).

CONCLUSIONS

For patients undergoing elective surgery of the pancreas, liver, stomach, and esophagus, considerable differences in demographic factors, frequency, and kind of NI exist. The consequences of NI force surgeons to analyze pre-operative risk factors carefully, assess indications for operation thoroughly, and optimize all controllable parameters.

Proposal for a sub-classification of hepato-biliary-pancreatic operations for surgical site infection surveillance following assessment of results of prospective multicenter data

BACKGROUND

Surgical site infection (SSI) surveillance in Japan is based on the National Nosocomial Infection Surveillance system, which categorizes all hepato-biliary-pancreatic surgeries, except for cholecystectomy, into "BILI." We evaluated differences among BILI procedures to determine the optimal subdivision for SSI surveillance.

METHODS

We conducted multicenter SSI surveillance at 20 hospitals. BILI was subdivided into choledochectomy, pancreatoduodenectomy, hepatectomy, hepatectomy with biliary reconstruction, pancreatoduodenectomy with hepatectomy, distal pancreatectomy and total pancreatectomy to determine the optimal subdivision. The outcome of interest was SSI. Univariate and multivariate analyses were performed to determine the predictive significance of variables in each type of surgery.

RESULTS

1,926 BILI cases were included in this study. SSI rates were 23.2 % for all BILI; for choledochectomy 23.6 %, pancreatoduodenectomy 39.3 %, hepatectomy 12.8 %, hepatectomy with biliary reconstruction 41.9 %, pancreatoduodenectomy with hepatectomy 27.3 %, distal pancreatectomy 31.8 %, and total pancreatectomy 20.0 %. SSI rates for hepatectomy were significantly lower than those for non-hepatectomy BILI. Risk factors for developing SSI with hepatectomy were drain placement and long operative duration, while for non-hepatectomy BILI, risk factors were use of intra-abdominal silk sutures, SSI risk index and long operative duration.

CONCLUSIONS

Hepatectomy and non-hepatectomy BILI differ with regard to the incidence of and risk factors for developing SSI. These surgeries should be assessed separately when conducting SSI surveillance.

Perioperative antibiotics for surgical site infection in pancreaticoduodenectomy: does the SCIP-approved regimen provide adequate coverage?

INTRODUCTION

The Joint Commission Surgical Care Improvement Project (SCIP) includes performance measures aimed at reducing surgical site infections (SSI). One measure defines approved perioperative antibiotics for general operative procedures. However, there may be a subset of procedures not adequately covered with the use of approved antibiotics. We hypothesized that piperacillin-tazobactam is a more appropriate perioperative antibiotic for pancreaticoduodenectomy (PD).

METHODS

In collaboration with hospital epidemiology and the Division of Infectious Diseases, we retrospectively reviewed records of 34 patients undergoing PD between March and May 2008 who received SCIP-approved perioperative antibiotics and calculated the SSI rate. After changing our perioperative antibiotic to piperacillin-tazobactam, we prospectively reviewed PDs performed between June 2008 and March 2009 and compared the SSI rates before and after the change.

RESULTS

For 34 patients from March through May 2008, the SSI rate for PD was 32.4 per 100 cases. Common organisms from wound cultures were Enterobacter and Enterococcus (50.0% and 41.7%, respectively), and these were cefoxitin resistant. From June 2008 through March 2009, 106 PDs were performed. During this period, the SSI rate was 6.6 per 100 surgeries, 80% lower than during March through May 2008 (relative risk, 0.204; 95% confidence interval [CI], 0.086-0.485; P = .0004).

CONCLUSION

Use of piperacillin-tazobactam as a perioperative antibiotic in PD may reduce SSI compared with the use of SCIP-approved antibiotics. Continued evaluation of SCIP performance measures in relationship to patient outcomes is integral to sustained quality improvement.

Risk factor of surgical site infection after pancreaticoduodenectomy

BACKGROUND

Although surgical site infection (SSI) following pancreaticoduodenectomy is a common complication, the risk factors remain unclear.

PATIENTS AND METHODS

A retrospective study of 408 consecutive patients undergoing pancreaticoduodenectomy was conducted and the risk factors for SSI were assessed. The bacterial composition was also analyzed.

RESULTS

Sixty-one patients developed incisional SSI, and 195 developed organ/space SSI. A multivariate analysis identified that length of operation>480 min (odds ratio [OR] 3.22), main pancreatic duct (MPD)≤3 mm (OR 2.18), and abdominal wall thickness>10 mm (OR 2.16) were significant risk factors for incisional SSI. The development of pancreatic fistula (OR 7.56), use of semi-closed drainage system (OR 3.68), body mass index>23.5 kg/m2 (OR 3.04), MPD≤3 mm (OR 2.21), and length of operation>480 min (OR 1.78) were significantly associated with organ/space SSI. Bacterial isolation at the SSI foci revealed that gut-derived micro-organisms were the predominant bacterial species.

CONCLUSIONS

The presence of pancreatic fistula was the strongest risk factor for organ/space SSI. Efforts to reduce the development of pancreatic fistulas, to decrease length of operation, and to use a closed drainage system would decrease the incidence of SSI following pancreaticoduodenectomy. If SSI that requires antibacterial treatment occurs, then the treatment should target enterobacteria.

C-reactive protein and interleukin-6 levels in the early detection of infection after open fractures

PURPOSE

To measure C-reactive protein (CRP) and interleukin-6 (IL-6) levels in 30 patients with open fractures and correlate the levels with infection.

METHODS

29 men and one woman aged 9 to 70 (mean, 37) years presented with open fractures of the upper or lower extremity within 12 hours of injury and underwent debridement and external fixation 3 to 40 (mean, 16) hours after injury. Serum CRP and IL-6 concentrations were measured preoperatively and on postoperative days 2 and 4. CRP was measured using latex agglutination and nephelometry, and IL-6 by enzyme-linked immunosorbent assay. The mean CRP and IL-6 levels in infected and non-infected patients were compared. The trend of CRP and IL-6 levels within the infected group was analysed. Correlations between CRP and infection, and between IL-6 and infection were analysed.

RESULTS

11 of the 30 patients developed wound infection. The day-2 CRP levels of 30 patients were positive (range, 7-28 µg/ml). In 27 patients, the CRP levels were higher on day 2 than preoperation. On day 4, CRP levels declined sharply in patients without infection (mean, 8 µg/ml) but were persistently elevated in patients with infection (mean, 17 µg/ml). The sensitivity and specificity of the CRP test were 100% and 42%, respectively. In the 11 patients with infection, the IL-6 concentrations were elevated at day 2 (mean, 689 pg/ml) and decreased progressively at day 4 (mean, 175 pg/ml). The sensitivity and specificity of the IL-6 test were 90% and 100%, respectively. Infection correlated with CRP and IL-6 levels.

CONCLUSIONS

Serial serum measurements of IL-6 and CRP levels help in the early diagnosis of infections after open fractures before they are clinically evident.

Anti-inflammatory effects of perioperative intensive insulin therapy during cardiac surgery with cardiopulmonary bypass

PURPOSE

Recent studies have reported that controlling blood glucose with insulin can suppress systemic inflammation. In the present study, we evaluated how perioperative intensive insulin therapy (IIT) influences the inflammatory response in an artificial pancreas during cardiac surgery with cardiopulmonary bypass.

METHODS

We randomly divided the patients undergoing cardiac surgery with cardiopulmonary bypass into two groups: an IIT group (n = 13) and a conventional treatment (CT) group (n = 12). For the IIT group, blood glucose control was initiated with an artificial pancreas at initiation of surgery. Blood glucose was maintained at 100 mg/dl until 24 h postoperatively. Blood samples were collected to determine changes in serum cytokine levels over time.

RESULTS

Patients' characteristics did not differ significantly between groups. Blood glucose levels were significantly higher in the CT group after surgery. Serum levels of tumor necrosis factor-α, interleukin-6, and high-mobility group box 1 were higher in the CT group than in the IIT group.

CONCLUSIONS

Use of IIT in the artificial pancreas during the perioperative period significantly decreased the inflammatory response. Moreover, we did not find evidence of hypoglycemia in those treated with IIT. This suggests that use of IIT in an artificial pancreas can be safe and effective for critically ill patients.

Single-Center Experience in Systemic Stress and Short-Term Morbidity of Single-Incision Cholecystectomy

Single-incision laparoscopic surgery (SILS) aims to reduce the number and size of skin incisions. The authors compared systemic stress and perioperative outcome of SILS and laparoscopic (LAP) cholecystectomy. Twenty-nine subjects (8 males and 21 females; mean age = 47 years; mean body mass index = 27) were included in the study. There was no statistical difference in mean operative time (LAP = 89 minutes; SILS = 113 minutes; P = ns), and no intraoperative complications were reported. There were no statistically significant differences observed in white cell count, C-reactive protein, interleukin-6, and tumor necrosis factor-α between SILS and LAP groups. The mean hospital length of stay (LAP = 1.8 days; SILS = 1.4 days) and Visual Analogue Scale scores for pain at 6 hours (LAP = 5.14; SILS = 4.46) and 24 hours (LAP = 3.9; SILS = 2.815) were similar with no perioperative morbidity. These results suggest that the systemic stress response in LAP and SILS cholecystectomy does not appear to be significantly different. SILS cholecystectomy appears safe with no perioperative morbidity or complications encountered in this series.

Evaluating systemic stress response in single port vs. multi-port laparoscopic cholecystectomy

BACKGROUND AND AIMS

Acute-phase proteins and inflammatory cytokines mediate measurable responses to surgical trauma, which are proportional to the extent of tissue injury and correlate with post-operative outcome. By comparing systemic stress following multi-port (LC) and single-incision laparoscopic cholecystectomy (SILC), we aim to determine whether reduced incision size induces a reduced stress response.

METHODS

Thirty-five consecutive patients were included, 11 underwent SILC (mean ± SEM; age 44.8 ± 3.88 year; BMI 27 ± 1.44 kg/m(2)) and 24 underwent LC (56.17 ± 2.80 year; 31.72 ± 1.07 kg/m(2), p < 0.05). Primary endpoint measures included levels of interleukin-6 and C-reactive protein measured pre- and post-operatively. Length-of-stay (LOS) and postoperative morbidity were secondary endpoints.

RESULTS

No statistically significant differences were found between SILC and LC for interleukin-6 and C-reactive protein levels, LOS and duration of surgery. There was also no correlation between systemic stress response and operative parameters. There were no intra-operative complications.

CONCLUSION

SILC appears to be a safe, feasible technique with potential advantages of cosmesis, reduced incisional pain, and well-being recommending its use. These data indicate no difference in systemic stress and morbidity between SILC and LC. A larger, multi-centred, randomised prospective trial is warranted to further investigate and confirm this finding.

IL-6 serum levels predict postoperative morbidity in gastric cancer patients

BACKGROUND

Despite progress in surgical techniques and perioperative care, gastrectomy remains a procedure of significant morbidity. Several scoring systems and clinical measures have been adopted to predict postoperative complications in gastric cancer patients. The aim of this study was to investigate whether high serum levels of interleukin 6 (IL-6) in the early postoperative period may be a prognostic factor of postoperative morbidity.

METHODS

A group of 99 consecutive patients with resectable gastric cancer were enrolled. The mean age was 62.9 years and the male/female ratio was 72:27. Subtotal gastric resection was performed in 22 patients and total gastric resection in 77. The IL-6 serum level was measured on the 1st postoperative day (POD).

RESULTS

Complications were recorded in 28 patients (28.3%). The observed case-fatality rate was 3.03%. An IL-6 serum level of >288.7 pg/ml on the 1st POD in univariate and multivariate Cox proportional hazard models was an independent prognostic factor for overall complications and infective complications.

CONCLUSION

Our study showed an association between perioperative IL-6 serum levels and postoperative morbidity in gastric cancer patients. The IL-6 serum level on the 1st POD was shown to be an independent prognostic factor for both overall complications and infective complications.

Two-component polyethylene glycol surgical sealant influence on intraperitoneal infection in a refined rodent model

OBJECTIVE

This study determined the influence of a 2-component polyethylene glycol surgical sealant (Coseal) as an adhesion prevention device on sepsis-related mortality and/or systemic bacterial translocation to the spleen.

STUDY DESIGN

A bacterial inoculum and telemetry probe were implanted in 50 treated and 49 untreated rats. Telemetry probes monitored core-body temperature to determine time of death. Spleens were collected on day 3 for quantitative bacteriology of Escherichia coli and Bacteroides fragilis.

RESULTS

Median survival time and mortality of treated rats (37.0 hours, 54.0%) were noninferior to untreated rats (47.5 hours, 55.1%). Median E coli titers in treated rats (2.24 log colony forming units/spleen) were significantly less than untreated rats (4.32 log colony forming units/spleen). B fragilis titers were not different.

CONCLUSION

This study demonstrates intraperitoneal administration of a 2-component polyethylene glycol surgical sealant as an adhesion prevention device does not alter time to death or sepsis-related mortality and/or systemic bacterial translocation to the spleen.

MCP-1 and MIP-1α expression in a model resembling early immune response to dengue

Dengue virus has become endemic in most tropical urban areas throughout the world, and DHF has appeared concomitantly with this expansion. The intensity of dengue virus replication during the early stages of infection could determine clinical outcomes; therefore, it is important to understand the impact of dengue virus infection on the earliest immune defense against microbial infection, which also strongly regulates the adaptive immune responses. This study was aimed at evaluating the expression of the CC-chemokines MIP-1α/CCL3 and MCP-1/CCL2 in peripheral blood leukocytes using an ex vivo model resembling dengue infection in vivo, in subjects with a well characterized dengue immune background, due to the exceptional Cuban epidemiological situation in dengue. The expression of IFNγ, TNFα and IL10 was also evaluated, giving insight about the role of MCP-1 and MIP-1α in the interplay between innate and adaptive immunity. From individuals with different dengue immune background after dengue virus challenge, increased and different expression of the chemokines and cytokines studied was verified in peripheral blood mononuclear cells, thus demonstrating that the previous immunity to a dengue virus serotype has a strong influence on the early immune response after dengue re-infection.

Chronic wounds and the medical biofilm paradigm

There is a growing recognition that biofilms are the principal cause of wound chronicity. The development of treatments for wound biofilms raises the prospect that chronic wounds can be treated, potentially saving many patients' lives.

Dietary restriction modifies certain aspects of the postoperative acute phase response

BACKGROUND

Lifespan extension is achieved through long-term application of dietary restriction (DR), and benefits of short-term dietary restriction on acute stress and inflammation have been observed. So far, the effects of short-term DR in humans are relatively unknown. We hypothesized that short-term DR in humans reduces the acute phase response following a well defined surgical trauma.

METHODS

Thirty live kidney donors were randomized between 30% preoperative dietary restriction followed by 1 d of fasting (n=17) or a 4 d ad libitum regimen (n=13) prior to surgery. Leukocyte subsets and numbers and serum cytokine levels were determined. Whole blood was stimulated with lipopolysaccharide (LPS) and cytokine production was determined.

RESULTS

A clear trend towards lower numbers of postoperative circulating leukocytes was observed in the DR group. IL-8 serum levels were significantly higher in the DR group over the first 6 postoperative d (P=0.018). After LPS stimulation, significantly less TNF-α (P=0.001) was produced by blood obtained postoperatively compared with preoperative blood from the DR group. This was not observed in the control group.

CONCLUSIONS

A relatively short preoperative dietary restriction regimen was able to modify certain aspects of the postoperative acute phase response. These data warrant further studies into the dietary conditions that improve stress resistance in humans. (Dutch Trial Registry number: NTR1875).

Circulating cytokines after hip and knee arthroplasty: a preliminary study

Several studies show cytokine concentrations in the peripheral blood are associated with inflammatory activity and surgical trauma. Cytokine concentrations have more rapid increase and quicker return to normal values than either C-reactive protein or erythrocyte sedimentation rate - a matter of hours rather than weeks; some studies suggest they are better predictors of postoperative infection than C-reactive protein and erythrocyte sedimentation rate. Threshold levels of interleukin-6 after joint arthroplasty have been determined, but levels of other potentially useful cytokines (tumor necrosis factor-alpha, interleukin-8, interleukin-10, etc) are not known. We measured the serum levels of 25 different cytokines before and after hip and knee arthroplasties and identified those associated with surgical trauma. Peripheral venous blood samples (one preoperative and three postoperative) from 49 patients undergoing hip or knee arthroplasty were analyzed by laser chromatography. Three of the 25 cytokines had a relationship with postsurgical trauma, which included one deep infection. Serum levels of these three cytokines might be useful to identify periprosthetic infections during the early postoperative period when C-reactive protein and erythrocyte sedimentation rate remain elevated.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Psychological stress induces hypoferremia through the IL-6-hepcidin axis in rats

Anemia is a widespread public health problem. The psychological stress decreases serum iron level and inhibits erythropoiesis. However, the molecular mechanisms involved, leading to iron mal-regulation are not well known. We used a communication box paradigm to induce psychological stress and found that serum iron level decreased after 3d while liver iron storage increased after 7d. Moreover, psychological stress up-regulated expressions of interleukin-6 (IL-6) and hepcidin, while down-regulating ferroportin expression after 3d. These changes were blocked by the injection of IL-6 monoclonal antibody. In conclusion, the IL-6-hepcidin axis is up-regulated by psychological stress in rats, resulting in hypoferremia and increase of hepatic iron storage.

Elevated interleukin-6 and G-CSF in human pancreatic cancer cell conditioned medium suppress dendritic cell differentiation and activation

Although dendritic cell (DC) function is impaired in pancreatic cancer patients, the underlying mechanisms are unknown. This study analyzed the soluble factors released by pancreatic cancer cells responsible for inhibiting DC differentiation and activation. Medium conditioned by a highly metastatic human pancreatic cancer cell line BxPC-3 [BxPC-3 conditioned medium (BxCM)] was mainly used for the study. Both CD34+ hematopoietic progenitor cell-derived and CD14+ monocyte-derived immature DCs and mature DCs (mDCs) were inhibited by BxCM. Allostimulation of CD4+ and CD8+ T cells by BxCM-treated mDCs was inefficient and resulted in production of lower levels of Th1 and Th2 cytokines. Antigen-specific T-cell activation capability was also reduced in BxCM-treated mDCs. Addition of exogenous interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF), which were present in high amounts in BxCM, mimicked the inhibitory effect of BxCM on DC differentiation and maturation. IL-6 was able to suppress DC differentiation and G-CSF mainly acted on the suppressing allostimulatory capacity of DCs. In addition, pancreatic cancer patient sera were able to inhibit DC differentiation of CD14+ monocytes obtained from healthy donors. Depleting IL-6 or G-CSF from BxCM could reverse the DC-inhibitory properties of BxCM. Furthermore, BxCM, IL-6, or G-CSF led to the activation of signal transducer and activator of transcription 3 (STAT3) in CD14+ monocytes to different degrees. Blocking BxCM-induced STAT3 activation also reversed the inhibitory effect of BxCM on DC differentiation. Therefore, IL-6 and G-CSF in BxCM represent two main factors responsible for suppression of DC differentiation, maturation, and antigen presentation, and this suppression of DC functions may be due to the aberrant activation of STAT3 by BxCM.