Trial of short-course antimicrobial therapy for intraabdominal infection

Clinical impact of non-antibiotic recommendations by a multi-disciplinary antimicrobial stewardship team

INTRODUCTION

The multi-disciplinary antimicrobial stewardship team at the study hospital conducts prospective review and feedback on all inpatient orders of piperacillin-tazobactam and carbapenems. In addition, the team provides non-antibiotic recommendations (i.e. additional investigations and infectious disease reviews). This study aimed to describe the impact of these recommendations on patient outcomes.

METHODS

Patients on carbapenem and piperacillin-tazobactam who received at least one non-antibiotic recommendation between January 2012 and August 2014 were included in this study. Acceptance and rejection of non-antibiotic recommendations by the managing physician were compared. The primary outcome was 30-d mortality.

RESULTS

Non-antibiotic recommendations were made in 166 patients. There were no differences in baseline characteristics between patients for whom recommendations were accepted and patients for whom recommendations were rejected. Thirty-day mortality (18.0% vs. 34.5%, P = 0.02) was significantly lower in patients who had at least one non-antibiotic recommendation accepted. Multi-variate analysis found that Charlson's comorbidity score [odds ratio (OR) 1.20, 95% confidence interval (CI) 1.03-1.42, P = 0.03], APACHE II score (OR 1.10, 95% CI 1.01-1.19, P < 0.01), hepatobiliary source of infection (OR 10.19, 95% CI 1.44-72.13, P = 0.02) and acceptance of at least one non-antibiotic recommendation (OR 0.39, 95% CI 0.17-0.88, P = 0.02) were independently associated with 30-d mortality.

CONCLUSIONS

During prospective review and feedback of piperacillin-tazobactam and carbapenems, acceptance of non-antibiotic recommendations was found to be associated with a reduction in 30-d mortality.

Post-operative management of perforated appendicitis: Can clinical pathways improve outcomes?

BACKGROUND

We sought to decrease organ space infection (OSI) following appendectomy for perforated acute appendicitis (PAA) by minimizing variation in clinical management.

OBJECTIVE

A postoperative treatment pathway was developed and four recommendations were implemented: 1) clear documentation of post-operative diagnosis, 2) patients with unknown perforation status to be treated as perforated pending definitive diagnosis, 3) antibiotic therapy to be continued post operatively for 4-7 days after SIRS resolution, and 4) judicious use of abdominal computed tomography (CT) scanning prior to post-operative day 5. Patient demographics and potential clinical predictors of OSI were captured. The primary end point was development of OSI within 30 days of discharge. Secondary endpoints included length of stay (LOS), readmission rate, other complications and secondary procedures performed.

RESULTS

A total of 1246 appendectomies were performed and we excluded patients <18 years (n = 205), interval appendectomies (n = 51) or appendectomies for other diagnosis (n = 37). Among the remaining 953 patients, 133 (14.0%) were perforated and 21 of these (15.8%) developed OSI. Comparing pre (n = 91) to post (n = 42) protocol patients, we saw similar rates of OSI (16.5 vs 14.3%, p = 0.75) with a peak in OSI development immediately prior to protocol implementation which dropped to baseline levels 1 year later based on CUSUM analysis. Readmission rates fell by 49.7% (14.3 vs 7.1%, p = 0.39) without increase in LOS (5.3 vs 5.7 days, p = 0.55) comparing patients pre and post protocol, although these results did not reach clinical significance.

CONCLUSIONS

The implementation of and compliance with a post-operative protocol status post appendectomy for PAA demonstrated a trend towards diminishing readmission rates and decreased utilization of CT imaging, but did not affect OSI rates. Additional approaches to diminishing OSI following management of perforated appendicitis need to be evaluated.

Treating Wisely: The Surgeon's Role in Antibiotic Stewardship

: Antibiotic resistance continues to receive national attention as a leading public health threat. In 2015, President Barack Obama proposed a National Action Plan to Combat Antibiotic-Resistant Bacteria to curb the rise of "superbugs," bacteria resistant to antibiotics of last resort. Whereas many antibiotics are prescribed appropriately to treat infections, there continue to be a large number of inappropriately prescribed antibiotics. Although much of the national attention with regards to stewardship has focused on primary care providers, there is a significant opportunity for surgeons to embrace this national imperative and improve our practices. Local quality improvement efforts suggest that antibiotic misuse for surgical disease is common. Opportunities exist as part of day-to-day surgical care as well as through surgeons' interactions with nonsurgeon colleagues and policy experts. This article discusses the scope of the antibiotic misuse in surgery for surgical patients, and provides immediate practice improvements and also advocacy efforts surgeons can take to address the threat. We believe that surgical antibiotic prescribing patterns frequently do not adhere to evidence-based practices; surgeons are in a position to mitigate their ill effects; and antibiotic stewardship should be a part of every surgeons' practice.

Aggressive Antimicrobial Initiation for Suspected Intensive Care Unit-Acquired Infection Is Associated with Decreased Long-Term Survival after Critical Illness

BACKGROUND

The long-term significance of early and prolonged antibiotic use in critically ill patients is yet to be described. Several studies suggest that antimicrobial exposure may have as yet unrecognized long-term effects on clinically meaningful outcomes. Our group previously conducted a quasi-experimental, before and after observational cohort study of hemodynamically stable surgical patients suspected of having an intensive care unit-acquired infection. This study demonstrated that aggressive initiation of antimicrobial therapy was associated with increased 30-day deaths. In a follow-up survival analysis, we hypothesized that aggressive antimicrobial treatment would not be a significant predictor of long-term death.

METHODS

Survival data for the 201 patients included in the initial study were obtained from our clinical data repository. Univariable analysis, Kaplan-Meier, and Cox proportional hazards models were used. Survival was evaluated at one and four years. Age, gender, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and co-morbidities were chosen a priori for potential inclusion in the model. Variables that met the model assumptions after testing were included in the final model.

RESULTS

Follow-up data were available for 190 patients (95 in each group) representing 94.5% of the initial cohort. Twenty-four (25.3%) patients in the aggressive group had initial APACHE II scores of less than 15 compared with 13 (13.7%) patients in the conservative group (p = 0.04). There was a trend toward higher deaths in the aggressive group at four years (41.1% vs. 30.5%; p = 0.13). Kaplan-Meier analysis demonstrated a difference in survival at one year but not at four years. The Cox proportional hazards model showed a higher long-term death for patients in the aggressive antimicrobial group at both one and four years (hazard rate: 2.26 and 1.70, respectively).

CONCLUSION

Aggressive initiation of antimicrobial therapy is independently associated with decreased long-term survival after critical illness. While further work is needed to confirm these findings, waiting for evidence of infection before initiation of antibiotic agents may be beneficial.

Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016

OBJECTIVE

To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012."

DESIGN

A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development.

METHODS

The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable.

RESULTS

The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions.

CONCLUSIONS

Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.

The Surgical Infection Society Revised Guidelines on the Management of Intra-Abdominal Infection

BACKGROUND

Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations.

METHODS

Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council.

RESULTS

This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included.

SUMMARY

The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline.

Management of intra-abdominal infections: recommendations by the WSES 2016 consensus conference

This paper reports on the consensus conference on the management of intra-abdominal infections (IAIs) which was held on July 23, 2016, in Dublin, Ireland, as a part of the annual World Society of Emergency Surgery (WSES) meeting. This document covers all aspects of the management of IAIs. The Grading of Recommendations Assessment, Development and Evaluation recommendation is used, and this document represents the executive summary of the consensus conference findings.

Hostage to History: The Duration of Antimicrobial Treatment for Acute Streptococcal Pharyngitis

Oral antimicrobial treatment of acute streptococcal pharyngitis commonly is given for 10 days. An investigation was conducted of journal publications and textbooks from the dawn of the antimicrobial era to the present in order to discover the basis for this settled practice. Current treatment duration for acute streptococcal pharyngitis was established half a century ago under conditions significantly different from those currently encountered by the average clinician. The 10-day treatment standard evolved without scientific justification. There have been no therapeutic trials that have validated the necessity for 10 days of oral antimicrobial treatment. Yet, despite the lack of a scientific foundation, the rarity of acute rheumatic fever in developed countries, the high failure rate for streptococcal eradication and evidence that short-course therapy with a nonpenicillin antimicrobial yields equivalent eradication rates, the 10-day rule persists because of long clinical usage and the inherent power of the number 10. Efforts to change this clinical benchmark will likely meet with resistance from practicing physicians.

Recent developments in the surgical management of complex intra-abdominal infection

BACKGROUND

Current guidance on the management of sepsis often applies to infection originating from abdominal or pelvic sources, which presents specific challenges and opportunities for efficient and rapid source control. Advances made in the past decade are presented in this article.

METHODS

A qualitative systematic review was undertaken by searching standard literature databases for English-language studies presenting original data on the clinical management of abdominal and pelvic complex infection in adults over the past 10 years. High-quality studies relevant to five topical themes that emerged during review were included.

RESULTS

Important developments and promising preliminary work are presented, relating to: imaging and other diagnostic modalities; antimicrobial therapy and the importance of antimicrobial stewardship; the particular challenges posed by fungal sepsis; novel techniques in percutaneous and endoscopic source control; and current issues relating to surgical source control and managing the abdominal wound. Logistical challenges relating to rapid access to cross-sectional imaging, interventional radiology and operating theatres need to be addressed so that international benchmarks can be met.

CONCLUSION

Important advances have been made in the diagnosis, non-operative and surgical control of abdominal or pelvic sources, which may improve outcomes in the future. Important areas for continued research include the diagnosis and therapy of fungal infection and the challenges of managing the open abdomen.

The gut microbiome and the mechanism of surgical infection

BACKGROUND

Since the very early days of surgical practice, surgeons have recognized the importance of considering that intestinal microbes might have a profound influence on recovery from surgical diseases such as appendicitis and peritonitis. Although the pathogenesis of surgical diseases such as cholelithiasis, diverticulosis, peptic ulcer disease and cancer have been viewed as disorders of host biology, they are emerging as diseases highly influenced by their surrounding microbiota.

METHODS

This is a review of evolving concepts in microbiome sciences across a variety of surgical diseases and disorders, with a focus on disease aetiology and treatment options.

RESULTS

The discovery that peptic ulcer disease and, in some instances, gastric cancer can now be considered as infectious diseases means that to advance surgical practice humans need to be viewed as superorganisms, consisting of both host and microbial genes. Applying this line of reasoning to the ever-ageing population of patients demands a more complete understanding of the effects of modern-day stressors on both the host metabolome and microbiome.

CONCLUSION

Despite major advances in perioperative care, surgeons today are witnessing rising infection-related complications following elective surgery. Many of these infections are caused by resistant and virulent micro-organisms that have emerged as a result of human progress, including global travel, antibiotic exposure, crowded urban conditions, and the application of invasive and prolonged medical and surgical treatment. A more complete understanding of the role of the microbiome in surgical disease is warranted to inform the path forward for prevention.

Sepsis: Current Definition, Pathophysiology, Diagnosis, and Management

Sepsis is a clinical syndrome that results from the dysregulated inflammatory response to infection that leads to organ dysfunction. The resulting losses to society in terms of financial burden, morbidity, and mortality are enormous. We provide a review of sepsis, its underlying pathophysiology, and guidance for diagnosis and management of this common disease. Current established treatments include appropriate antimicrobial agents to target the underlying infection, optimization of intravascular volume to improve stroke volume, vasopressors to counteract vasoplegic shock, and high-quality supportive care. Appropriate implementation of established treatments combined with novel therapeutic approaches promises to continue to decrease the impact of this disease.

Current outcomes and predictors of treatment failure in patients with surgical site infection after elective colorectal surgery. A multicentre prospective cohort study

OBJECTIVE

To determine current outcomes and predictors of treatment failure among patients with surgical site infection (SSI) after colorectal surgery.

METHODS

A multicentre observational prospective cohort study of adults undergoing elective colorectal surgery in 10 Spanish hospitals (2011-2014). Treatment failure was defined as persistence of signs/symptoms of SSI or death at 30 days post-surgery.

RESULTS

Of 3701 patients, 669 (18.1%) developed SSI; 336 (9.1%) were organ-space infections. Among patients with organ-space SSI, 81.2% required source control: 60.4% reoperation and 20.8% percutaneous/transrectal drainage. Overall treatment failure rate was 21.7%: 9% in incisional SSIs and 34.2% in organ-space SSIs (p < 0.001). Median length of stay was 15 days (IQR 9-22) for incisional SSIs and 24 days (IQR 17-35) for organ-space SSIs (p < 0.001). One hundred and twenty-seven patients (19%) required readmission and 35 patients died (5.2%). Risk factors for treatment failure among patients with organ-space SSI were age ≥65 years (OR 1.83, 95% CI: 1.07-1.83), laparoscopy (OR 1.7, 95% CI: 1.06-2.77), and reoperation (OR 2.8, 95% CI: 1.7-4.6).

CONCLUSIONS

Rates of SSI and treatment failure in organ-space SSI after elective colorectal surgery are notably high. Careful attention should be paid to older patients with previous laparoscopy requiring reoperation for organ-space SSI, so that treatment failure can be identified early.

Proposal for shorter antibiotic therapies

OBJECTIVES

Reducing antibiotic consumption has now become a major public health priority. Reducing treatment duration is one of the means to achieve this objective. Guidelines on the therapeutic management of the most frequent infections recommend ranges of treatment duration in the ratio of one to two. The Recommendation Group of the French Infectious Diseases Society (SPILF) was asked to collect literature data to then recommend the shortest treatment durations possible for various infections.

METHODS

Analysis of the literature focused on guidelines published in French and English, supported by a systematic search on PubMed. Articles dating from one year before the guidelines publication to August 31, 2015 were searched on the website.

RESULTS

The shortest treatment durations based on the relevant clinical data were suggested for upper and lower respiratory tract infections, central venous catheter-related and uncomplicated primary bacteremia, infective endocarditis, bacterial meningitis, intra-abdominal, urinary tract, upper reproductive tract, bone and joint, skin and soft tissue infections, and febrile neutropenia. Details of analyzed articles were shown in tables.

CONCLUSION

This work stresses the need for new well-conducted studies evaluating treatment durations for some common infections. Following the above-mentioned work focusing on existing literature data, the Recommendation Group of the SPILF suggests specific study proposals.

Risk factors for excessively prolonged meropenem use in the intensive care setting: a case-contol study

Background

Inappropriate use of broad-spectrum antimicrobials affects adversely both the individual patient and the general public. The aim of the study was to identify patients at risk for excessively prolonged carbapenem treatment in the ICU as a target for antimicrobial stewardship interventions.

Methods

Case–control study in a network of 11 ICUs of a university hospital. Patients with uninterrupted meropenem therapy (MT) > 4 weeks were compared to controls. Controls were defined as patients who stayed on the ICU > 4 weeks and received meropenem for ≤ 2 weeks. Associations between case–control status and potential risk factors were determined in a multivariate logistic regression model.

Results

Between 1^st of January 2013 and 31^st of December 2015, we identified 36 patients with uninterrupted MT > 4 weeks. Patients with prolonged MT were more likely to be surgical patients (72.2% of cases vs. 31.5% of controls; p ≤ 0.001) with peritonitis being the most common infection (n = 16, 44.4%). In the multivariate logistic regression model colonization with multidrug-resistant (MDR) Gram-negative bacteria (OR 7.52; 95% CI 1.88–30.14, p = 0.004) and the type of infection (peritonitis vs. pneumonia: OR 16.96, 95% CI 2.95–97.49) were associated with prolonged MT.

Conclusion

Surgical patients with peritonitis and patients with known colonization with MDR Gram-negative bacteria are at risk for excessively prolonged carbapenem therapy and represent an important target population for antimicrobial stewardship interventions.

Clinical trials in surgical infection

Change is needed

Major publications in the critical care pharmacotherapy literature in 2015

PURPOSE

Recently published practice guidelines and research reports on pharmacotherapy in critical care patient populations are summarized.

SUMMARY

The Critical Care Pharmacotherapy Literature Update (CCPLU) Group is composed of over 50 experienced critical care pharmacists who evaluate 31 peer-reviewed journals monthly to identify literature pertaining to pharmacotherapy in critical care populations. Articles are chosen for summarization in a monthly CCPLU Group publication on the basis of applicability and relevance to clinical practice and strength of study design. From January to December 2015, a total of 121 articles were summarized; of these, 3 articles presenting clinical practice guidelines and 12 articles presenting original research findings were objectively selected for inclusion in this review based on their potential to change or reinforce current evidence-based practice. The reviewed guidelines address the management of intracranial hemorrhage (ICH), adult advanced cardiac life support (ACLS) and post-cardiac arrest care, and the management of supraventricular tachycardia (SVT). The reviewed research reports address topics such as nutrition in critically ill adults, administration of β-lactams for severe sepsis, anticoagulant selection in the context of continuous renal replacement therapy, early goal-directed therapy in septic shock, magnesium use for neuroprotection in acute stroke, and progesterone use in patients with traumatic brain injury.

CONCLUSION

Important recent additions to the critical care pharmacy literature include updated joint clinical practice guidelines on the management of spontaneous ICH, ACLS, and SVT.

Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016

OBJECTIVE

To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012".

DESIGN

A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development.

METHODS

The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable.

RESULTS

The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions.

CONCLUSIONS

Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.

Fever Is Associated with Reduced, Hypothermia with Increased Mortality in Septic Patients: A Meta-Analysis of Clinical Trials

Background

Sepsis is usually accompanied by changes of body temperature (T_b), but whether fever and hypothermia predict mortality equally or differently is not fully clarified. We aimed to find an association between T_b and mortality in septic patients with meta-analysis of clinical trials.

Methods

We searched the PubMed, EMBASE, and Cochrane Controlled Trials Registry databases (from inception to February 2016). Human studies reporting T_b and mortality of patients with sepsis were included in the analyses. Average T_b with SEM and mortality rate of septic patient groups were extracted by two authors independently.

Results

Forty-two studies reported T_b and mortality ratios in septic patients (n = 10,834). Pearson correlation analysis revealed weak negative linear correlation (R² = 0.2794) between T_b and mortality. With forest plot analysis, we found a 22.2% (CI, 19.2–25.5) mortality rate in septic patients with fever (T_b > 38.0°C), which was higher, 31.2% (CI, 25.7–37.3), in normothermic patients, and it was the highest, 47.3% (CI, 38.9–55.7), in hypothermic patients (T_b < 36.0°C). Meta-regression analysis showed strong negative linear correlation between T_b and mortality rate (regression coefficient: -0.4318; P < 0.001). Mean T_b of the patients was higher in the lowest mortality quartile than in the highest: 38.1°C (CI, 37.9–38.4) vs 37.1°C (CI, 36.7–37.4).

Conclusions

Deep T_b shows negative correlation with the clinical outcome in sepsis. Fever predicts lower, while hypothermia higher mortality rates compared with normal T_b. Septic patients with the lowest (< 25%) chance of mortality have higher T_b than those with the highest chance (> 75%).

Significant publications on infectious diseases pharmacotherapy in 2015

PURPOSE

The most important articles on infectious diseases (ID) pharmacotherapy published in the peer-reviewed literature in 2015, as nominated and selected by panels of pharmacists and others with ID expertise, are summarized.

SUMMARY

Members of the Houston Infectious Diseases Network were asked to nominate articles published in prominent peer-reviewed journals in 2015 that were thought to have a major impact in the field of ID pharmacotherapy. A list of 55 nominated articles on general ID-related topics and 10 articles specifically related to human immunodeficiency virus (HIV) infection or acquired immunodeficiency syndrome (AIDS) was compiled. In a national online survey, members of the Society of Infectious Diseases Pharmacists (SIDP) were asked to select from the list 10 general ID articles believed to have made a significant contribution to the field of ID pharmacotherapy and 1 article contributing to HIV/AIDS pharmacotherapy. Of the 361 SIDP members surveyed, 153 (42%) and 76 (21%) participated in the selection of general ID-related articles and HIV/AIDS-related articles, respectively. The 11 highest-ranked publications (10 general ID-related articles and 1 HIV/AIDS-related article) are summarized here.

CONCLUSION

With the growing number of significant ID-related publications each year, it can be challenging to stay current with the literature. This review of important ID pharmacotherapy publications in 2015 may be helpful in identifying key articles and lessening this burden.

The management of intra-abdominal infections from a global perspective: 2017 WSES guidelines for management of intra-abdominal infections

Intra-abdominal infections (IAIs) are common surgical emergencies and have been reported as major contributors to non-trauma deaths in the emergency departments worldwide. The cornerstones of effective treatment of IAIs are early recognition, adequate source control, and appropriate antimicrobial therapy. Prompt resuscitation of patients with ongoing sepsis is of utmost important. In hospitals worldwide, non-acceptance of, or lack of access to, accessible evidence-based practices and guidelines result in overall poorer outcome of patients suffering IAIs. The aim of this paper is to promote global standards of care in IAIs and update the 2013 WSES guidelines for management of intra-abdominal infections.

Age and Its Impact on Outcomes with Intra-Abdominal Infection

BACKGROUND

Age has been shown to play a significant role in the etiology of complicated intra-abdominal infections (cIAIs), but the correlation between age and outcomes after therapy was not investigated in the Study to Optimize Peritoneal Infection Therapy (STOP-IT) trial.

PATIENTS AND METHODS

Data were obtained by post hoc analysis of the STOP-IT trial database. Patients were stratified by age <65 or ≥65 years. Primary outcomes were surgical site infection (SSI), recurrent IAI (recIAI), and death. Multivariable analysis was performed to identify independent predictors of outcomes.

RESULTS

There were 398 subjects <65 and 120 ≥ 65 years. Overall baseline characteristics of the two groups were similar. The site of infection was similar between groups except: Colon or rectum (48.3% vs. 29.9%, p = 0.0002) and biliary tree (16.7% vs. 9.1%, p = 0.02), which were more common in the older group, whereas small intestine (6.7% vs. 16.3%, p = 0.008) and appendix (4.2% vs.17.1%, p = 0.0004) were more common in the younger group. Among the primary outcomes, only death was significantly different between the age groups and was more prevalent in the ≥65 years group (4 [3.3%] vs. 1 [0.3%], p = 0.01). Surgical site infection (9.2% vs. 7.3%, p = 0.50), recIAI (15.8% vs. 14.4%, p = 0.69), and a composite outcome (26.7% vs. 20.4%, p = 0.14) were statistically similar between the age groups, and this remained true when controlling for other co-variables. Multivariable analyses did not reveal age as an independent predictor of the composite or individual outcomes.

CONCLUSION

Patients with a more advanced age demonstrated variable sources of infection relative to the younger cohort, yet received similar treatments. Patient age was not an independent predictor of the undesired cIAI outcomes. These findings suggest that advanced age itself does not play a significant role in predicting these adverse outcomes for cIAIs and does not necessitate an altered treatment tactic.

External Validation of a Decision Tool To Guide Post-Operative Management of Patients with Secondary Peritonitis

BACKGROUND

Timely identification of patients in need of an intervention for abdominal sepsis after initial surgical management of secondary peritonitis is vital but complex. The aim of this study was to validate a decision tool for this purpose and to evaluate its potential to guide post-operative management.

METHODS

A prospective cohort study was conducted on consecutive adult patients undergoing surgery for secondary peritonitis in a single hospital. Assessments using the decision tool, based on one intra-operative and five post-operative variables, were performed on the second and third post-operative days and when the patients' clinical status deteriorated. Scores were compared with the clinical reference standard of persistent sepsis based on the clinical course or findings at imaging or surgery. Additionally, the potential of the decision tool to guide management in terms of diagnostic imaging in three previously defined score categories (low, intermediate, and high) was evaluated.

RESULTS

A total of 161 assessments were performed in 69 patients. The majority of cases of secondary peritonitis (68%) were caused by perforation of the gastrointestinal tract. Post-operative persistent sepsis occurred in 28 patients. The discriminative capacity of the decision tool score was fair (area under the curve of the receiver operating characteristic = 0.79). The incidence rate differed significantly between the three score categories (p < 0.001). The negative predictive value of a decision tool score categorized as low probability was 89% (95% confidence interval [CI] 82-94) and 65% (95% CI 47-79) for an intermediate score. Diagnostic imaging was performed more frequently when there was an intermediate score than when the score was categorized as low (46% vs. 24%; p < 0.001).

CONCLUSION

In patients operated on for secondary peritonitis, the decision tool score predicts with fair accuracy whether persistent sepsis is present.

Using Procalcitonin to Guide Antibiotic Therapy

Procalcitonin levels rise in response to systemic inflammation, especially of bacterial origin. Multiple randomized controlled trials have demonstrated that procalcitonin-based algorithms can safely reduce antibiotic use in 2 clinical scenarios. First, in stable, low-risk patients with respiratory infections, procalcitonin levels of <0.25 µg/L can guide the decision to withhold antibiotics or stop therapy early. Second, in critically ill patients with suspected sepsis, clinicians should not initially withhold antibiotics, but procalcitonin levels of <0.5 µg/L or levels that decrease by ≥80% from peak can guide discontinuation once patients stabilize. The recent stop antibiotics on procalcitonin guidance study (SAPS), the largest procalcitonin trial to date, demonstrated reduction in both antibiotic exposure and mortality in critically ill patients. Although procalcitonin is ready for routine use, future research should examine optimal strategies for implementation in hospitals, its real-world impact on clinical outcomes and costs, its applicability to immunocompromised patients, and the generalizability of trials to the US population.

Antimicrobial Stewardship: A Call to Action for Surgeons

Despite current antimicrobial stewardship programs (ASPs) being advocated by infectious disease specialists and discussed by national and international policy makers, ASPs coverage remains limited to only certain hospitals as well as specific service lines within hospitals. The ASPs incorporate a variety of strategies to optimize antimicrobial agent use in the hospital, yet the exact set of interventions essential to ASP success remains unknown. Promotion of ASPs across clinical practice is crucial to their success to ensure standardization of antimicrobial agent use within an institution. To effectively accomplish this standardization, providers who actively engage in antimicrobial agent prescribing should participate in the establishment and support of these programs. Hence, surgeons need to play a major role in these collaborations. Surgeons must be aware that judicious antibiotic utilization is an integral part of any stewardship program and necessary to maximize clinical cure and minimize emergence of antimicrobial resistance. The battle against antibiotic resistance should be fought by all healthcare professionals. If surgeons around the world participate in this global fight and demonstrate awareness of the major problem of antimicrobial resistance, they will be pivotal leaders. If surgeons fail to actively engage and use antibiotics judiciously, they will find themselves deprived of the autonomy to treat their patients.

Ceftazidime-avibactam for the treatment of complicated intra-abdominal infections

INTRODUCTION

The treatment of complicated intra-abdominal infections (cIAI) is increasingly challenging due to increased resistance of Gram-negative organisms. These multidrug resistant organisms lead to an increase in morbidity and mortality. This has led to renewed interest in use of older β-lactam antibiotics in combination with newer β-lactamase inhibitors. Ceftazidime-avibactam is one of the newest such combination antibiotics, which has been released for treatment of complicated intra-abdominal infections in combination with metronidazole. Areas covered: In this drug evaluation manuscript cIAI along with the chemistry, pharmacodynamics, pharmacokinetics, metabolism and clinical study results of ceftazidime-avibactam are reviewed. Expert opinion: The role of ceftazidime-avibactam in combination with metronidazole in the treatment of cIAI is still to be defined. Patients with cIAI known to be infected with Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae would be clear candidates for treatment with this agent, as would patients infected with more common types of extended-spectrum β-lactamase producing Gram-negative pathogens if a carbapenem alternative were desired. At present, it is difficult to establish a clear group of patients with cIAI for whom initial empiric therapy with this agent would be warranted.

Shorter Duration of Post-Operative Antibiotics for Cecal Ligation and Puncture Does Not Increase Inflammation or Mortality

Antimicrobial therapy for sepsis has beneficial effects, but prolonged use fosters emergence of resistant microorganisms, increases cost, and secondary infections. We tested whether 3 days versus 5 days of antibiotics in the murine model of cecal ligation and puncture (CLP) negatively influences outcomes. Following CLP mice were randomized to receive the antibiotic imipenem-cilastatin (25mg/kg) in dextrose 5% in Lactated Ringer’s solution every 12 hours for either three or five days. Serial monitoring over 28 days included body weight, temperature, pulse oximetry, and facial vein sampling for hematological analysis and glucose. A separate group of mice were euthanized on post-CLP day 5 to measure cytokines and peritoneal bacterial counts. The first study examined no antimicrobial therapy and demonstrated that antibiotics significantly improved survival compared to fluids only (p = 0.004). We next tested imipenem-cilastatin therapy for 3 days versus 5 days. Body weight, temperature, glucose, and pulse oximetry measurements remained generally consistent between both groups as did the hematological profile. Pro-inflammatory plasma cytokines were comparable between both groups for IL-6, IL-1β, MIP-2 and anti-inflammatory cytokines IL-10, and TNF SRI. At 5 days post-CLP, i.e. 2 days after the termination of antibiotics in the 3 day group, there were no differences in the number of peritoneal bacteria. Importantly, shortening the course of antibiotics by 40% (from 5 days to 3 days) did not decrease survival. Our results indicate that reducing the duration of broad-spectrum antibiotics in murine sepsis did not increase inflammation or mortality.

Complicated Intra-Abdominal Infections: The Old Antimicrobials and the New Players

Complicated intra-abdominal infections (cIAIs) are an important cause of morbidity and mortality worldwide. They are diagnosed when the initial abdominal organ infection has spread into the peritoneal space. Successful treatment relies on adequate source control and appropriate empiric antimicrobial therapy. Inappropriate antimicrobial therapy may result in poor patient outcomes and increases in healthcare costs. Current guidelines recommend several single and combination antimicrobial regimens; however, empiric antimicrobial treatment has been complicated by the increasing rates of resistant organisms, especially the extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Additionally, the overuse of carbapenems to combat these resistant pathogens has contributed to the rise of carbapenemase-producing microorganisms, especially Klebsiella pneumoniae. This increasing resistance has prompted the development of novel antimicrobials like ceftazidime-avibactam and ceftolozane-tazobactam, whose activity extends to ESBL-producing microorganisms. Furthermore, the optimal duration of antimicrobial therapy is still unknown, and further research is necessary to find a definitive answer. This review will focus on antimicrobial therapies recommended by the current guidelines, the individual properties of these agents, appropriate duration of therapy, recent clinical trials, and place in therapy of the antimicrobial agents recently approved for the treatment of cIAIs.

Retrospective Multicenter Study on Risk Factors for Surgical Site Infections after Appendectomy for Acute Appendicitis

BACKGROUND

Surgical site infections (SSI) are seen in up to 5% of patients after appendectomy for acute appendicitis. SSI are associated with prolonged hospital stay and increased costs. The aim of this multicenter study was to identify factors associated with SSI after appendectomy for acute appendicitis.

METHODS

Patients who underwent appendectomy for acute appendicitis between June 2014 and January 2015 in 6 teaching hospitals in the southwest of the Netherlands were included. Patient, diagnostic, intra-operative and disease-related factors were collected from the patients' charts. Primary outcome was surgical site infection. Multivariable logistic regression was performed to identify independent risk factors for SSI.

RESULTS

Some 637 patients were included. Forty-two patients developed a SSI. In univariable analysis body temperature >38°C, CRP>65 and complex appendicitis were associated with SSI. After multivariable logistic regression with stepwise backwards elimination, complex appendicitis was significantly associated with SSI (OR 4.09; 95% CI 2.04-8.20). Appendiceal stump closure with a stapler device was inversely correlated with SSI (OR 0.40; 95% CI 0.24-0.97) Conclusions: Complex appendicitis is a risk factor for SSI and warrants close monitoring postoperatively. The use of a stapler device for appendiceal stump closure is associated with a reduced risk of SSI.

Patients with Risk Factors for Complications Do Not Require Longer Antimicrobial Therapy for Complicated Intra-Abdominal Infection

A prospective, multicenter, randomized controlled trial found that four days of antibiotics for source-controlled complicated intra-abdominal infection resulted in similar outcomes when compared with a longer duration. We hypothesized that patients with specific risk factors for complications also had similar outcomes. Short-course patients with obesity, diabetes, or Acute Physiology and Chronic Health Evaluation II ≥15 from the STOP-IT trial were compared with longer duration patients. Outcomes included incidence of and days to infectious complications, mortality, and length of stay. Obese and diabetic patients had similar incidences of and days to surgical site infection, recurrent intra-abdominal infection, extra-abdominal infection, and Clostridium difficile infection. Short- and long-course patients had similar incidences of complications among patients with Acute Physiology and Chronic Health Evaluation II ≥15. However, there were fewer days to the diagnosis of surgical site infection (9.5 ± 3.4 vs 21.6 ± 6.2, P = 0.010) and extra-abdominal infection (12.4 ± 6.9 vs 21.8 ± 6.1, P = 0.029) in the short-course group. Mortality and length of stay was similar for all groups. A short course of antibiotics in complicated intraabdominal infection with source control seems to have similar outcomes to a longer course in patients with diabetes, obesity, or increased severity of illness.

Inclusion of Vancomycin as Part of Broad-Spectrum Coverage Does Not Improve Outcomes in Patients with Intra-Abdominal Infections: A Post Hoc Analysis

BACKGROUND

Management of complicated intra-abdominal infections (cIAIs) includes broad-spectrum antimicrobial coverage and commonly includes vancomycin for the empiric coverage of methicillin-resistant Staphylococcus aureus (MRSA). Ideally, culture-guided de-escalation follows to promote robust antimicrobial stewardship. This study assessed the impact and necessity of vancomycin in cIAI treatment regimens.

PATIENTS AND METHODS

A post hoc analysis of the Study to Optimize Peritoneal Infection Therapy (STOP-IT) trial was performed. Patients receiving piperacillin-tazobactam (P/T) and/or a carbapenem were included with categorization based on use of vancomycin. Univariate and multivariable analyses evaluated effects of including vancomycin on individual and the composite of undesirable outcomes (recurrent IAI, surgical site infection [SSI], or death).

RESULTS

The study cohort included 344 patients with 110 (32%) patients receiving vancomycin. Isolation of MRSA occurred in only eight (2.3%) patients. Vancomycin use was associated with a similar composite outcome, 29.1%, vs. no vancomycin, 22.2% (p = 0.17). Patients receiving vancomycin had (mean [standard deviation]) higher Acute Physiology and Chronic Health Evaluation II scores (13.1 [6.6] vs. 9.4 [5.7], p < 0.0001), extended length of stay (12.6 [10.2] vs. 8.6 [8.0] d, p < 0.001), and prolonged antibiotic courses (9.1 [8.0] vs. 7.1 [4.9] d, p = 0.02). After risk adjustment in a multivariate model, no significant difference existed for the measured outcomes.

CONCLUSIONS

This post hoc analysis reveals that addition of vancomycin occurred in nearly one third of patients and more often in sicker patients. Despite this selection bias, no appreciable differences in undesired outcomes were demonstrated, suggesting limited utility for adding vancomycin to cIAI treatment regimens.

Ten key points for the appropriate use of antibiotics in hospitalised patients: a consensus from the Antimicrobial Stewardship and Resistance Working Groups of the International Society of Chemotherapy

The Antibiotic Stewardship and Resistance Working Groups of the International Society for Chemotherapy propose ten key points for the appropriate use of antibiotics in hospital settings. (i) Get appropriate microbiological samples before antibiotic administration and carefully interpret the results: in the absence of clinical signs of infection, colonisation rarely requires antimicrobial treatment. (ii) Avoid the use of antibiotics to 'treat' fever: use them to treat infections, and investigate the root cause of fever prior to starting treatment. (iii) Start empirical antibiotic treatment after taking cultures, tailoring it to the site of infection, risk factors for multidrug-resistant bacteria, and the local microbiology and susceptibility patterns. (iv) Prescribe drugs at their optimal dosing and for an appropriate duration, adapted to each clinical situation and patient characteristics. (v) Use antibiotic combinations only where the current evidence suggests some benefit. (vi) When possible, avoid antibiotics with a higher likelihood of promoting drug resistance or hospital-acquired infections, or use them only as a last resort. (vii) Drain the infected foci quickly and remove all potentially or proven infected devices: control the infection source. (viii) Always try to de-escalate/streamline antibiotic treatment according to the clinical situation and the microbiological results. (ix) Stop unnecessarily prescribed antibiotics once the absence of infection is likely. And (x) Do not work alone: set up local teams with an infectious diseases specialist, clinical microbiologist, hospital pharmacist, infection control practitioner or hospital epidemiologist, and comply with hospital antibiotic policies and guidelines.

WSES Jerusalem guidelines for diagnosis and treatment of acute appendicitis

Acute appendicitis (AA) is among the most common cause of acute abdominal pain. Diagnosis of AA is challenging; a variable combination of clinical signs and symptoms has been used together with laboratory findings in several scoring systems proposed for suggesting the probability of AA and the possible subsequent management pathway. The role of imaging in the diagnosis of AA is still debated, with variable use of US, CT and MRI in different settings worldwide. Up to date, comprehensive clinical guidelines for diagnosis and management of AA have never been issued. In July 2015, during the 3rd World Congress of the WSES, held in Jerusalem (Israel), a panel of experts including an Organizational Committee and Scientific Committee and Scientific Secretariat, participated to a Consensus Conference where eight panelists presented a number of statements developed for each of the eight main questions about diagnosis and management of AA. The statements were then voted, eventually modified and finally approved by the participants to The Consensus Conference and lately by the board of co-authors. The current paper is reporting the definitive Guidelines Statements on each of the following topics: 1) Diagnostic efficiency of clinical scoring systems, 2) Role of Imaging, 3) Non-operative treatment for uncomplicated appendicitis, 4) Timing of appendectomy and in-hospital delay, 5) Surgical treatment 6) Scoring systems for intra-operative grading of appendicitis and their clinical usefulness 7) Non-surgical treatment for complicated appendicitis: abscess or phlegmon 8) Pre-operative and post-operative antibiotics.

New Approaches to Antibiotic Use and Review of Recently Approved Antimicrobial Agents

Antimicrobial drug-resistance continues to force adaptation in our clinical practice. We explore new evidence regarding adjunctive antibiotic therapy for skin and soft tissue abscesses as well as duration of therapy for intra-abdominal abscesses. As new evidence refines optimal practice, it is essential to support clinicians in adopting practice patterns concordant with evidence-based guidelines. We review a simple approach that can 'nudge' clinicians towards concordant practices. Finally, the use of novel antimicrobials will play an increasingly important role in contemporary therapy. We review five new antimicrobials recently FDA-approved for use in drug-resistant infections: dalbavancin, oritavancin, ceftaroline, ceftolozane-tazobactam, and ceftazidime-avibactam.

Abdominal Sepsis

Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy.

Antibiotic strategies in the era of multidrug resistance

The rapid emergence and dissemination of antibiotic-resistant microorganisms in ICUs worldwide threaten adequate antibiotic coverage of infected patients in this environment. The causes of this problem are multifactorial, but the core issues are clear: the emergence of antibiotic resistance is highly correlated with selective pressure resulting from inappropriate use of these drugs. Because a significant increase in mortality is observed when antibiotic therapy is delayed in infected ICU patients, initial therapy should be broad enough to cover all likely pathogens. Receipt of unnecessary prolonged broad-spectrum antibiotics, however, should be avoided. Local microbiologic data are extremely important to predict the type of resistance that may be present for specific causative bacteria, as is prior antibiotic exposure, and antibiotic choices should thus be made at an individual patient level.

Procalcitonin-guided antibiotic treatment in critically ill patients

PURPOSE

In critically ill patients, length of antibiotic treatment can be effectively guided by procalcitonin (PCT) protocols. International sepsis guidelines and guidelines on antibiotic stewardship strategies recommend PCT as helpful laboratory marker for a rational use of antibiotics. A number of studies and meta-analyses have confirmed the effectiveness of PCT-protocols for shortening antibiotic treatment without compromising clinical outcome in critically ill patients. But in clinical practice, there is still uncertainty how to interpret PCT levels and how to adjust antibiotic treatment in various infectious situations, especially in the perioperative period.

METHODS

This narrative review gives an overview on the application of PCT-protocols in critically ill patients with severe bacterial infections on the basis of 5 case reports and the available literature. Beside strengths and limitations of this biomarker, also varying kinetics and different maximum values with regard to the infectious focus and pathogens are discussed.

RESULTS

PCT-guided antibiotic treatment appears to be safe and effective. Most of the studies revealed a shorter antibiotic treatment without negative clinical outcomes. Cost effectiveness is still a matter of debate and effects on bacterial resistance due to shorter treatments, possible lower rates of drug-related adverse events, or decreased rates of Clostridium difficile infections are not yet evaluated.

CONCLUSION

Guidance of antibiotic treatment can effectively be supported by PCT-protocols. However, it is important to consider the limitations of this biomarker and to use PCT protocols along with antibiotic stewardship programmes and regular clinical rounds together with infectious diseases specialists.

Critical evaluation of ceftolozane-tazobactam for complicated urinary tract and intra-abdominal infections

The rise in resistant Gram-negative pathogens continues to challenge clinicians treating infections. These resistant infections have inspired the development of new antimicrobial agents, including ceftolozane-tazobactam, a novel β-lactam/β-lactamase inhibitor combination approved by the US Food and Drug Administration for the treatment of complicated urinary tract infections (cUTIs) and complicated intra-abdominal infections (cIAIs) in combination with metronidazole. Ceftolozane exhibits bactericidal activity by inhibiting penicillin-binding proteins (PBPs), with high affinity for PBP1b, PBP1c, and PBP3. The addition of tazobactam protects ceftolozane from hydrolysis by irreversibly binding to some β-lactamase enzymes. Ceftolozane-tazobactam is active against a wide range of Gram-negative pathogens, including extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and multidrug-resistant (MDR) Pseudomonas aeruginosa, several streptococcal species, and Bacteroides fragilis. When anaerobic coverage is needed, it should be used in combination with metronidazole. Ceftolozane demonstrates linear pharmacokinetics, low protein binding, and minimal accumulation with repeated dosing. The major pharmacokinetic/pharmacodynamic index for ceftolozane is the percentage of the dosing interval in which the plasma free drug concentration remains higher than the minimum inhibitory concentration (%T.MIC). Phase III clinical trials for the treatment of cUTIs and cIAIs have been completed, showing that it is an effective and safe alternative for the treatment of these infections. The approved dose for cUTIs and cIAIs is 1.5 g (1 g ceftolozane and 500 mg tazobactam) infused over 1 hour every 8 hours. A higher 3 g dose is currently in Phase III trials for the treatment of ventilated nosocomial pneumonia. Dosage adjustments are necessary for patients with moderate-to-severe renal impairment. Current data suggest that ceftolozane-tazobactam is a promising carbapenem-sparing alternative agent for the treatment of cUTIs and cIAIs, including those caused by ESBL-producing Enterobacteriaceae and MDR P. aeruginosa.

Advances in antibiotic therapy in the critically ill

Infections occur frequently in critically ill patients and their management can be challenging for various reasons, including delayed diagnosis, difficulties identifying causative microorganisms, and the high prevalence of antibiotic-resistant strains. In this review, we briefly discuss the importance of early infection diagnosis, before considering in more detail some of the key issues related to antibiotic management in these patients, including controversies surrounding use of combination or monotherapy, duration of therapy, and de-escalation. Antibiotic pharmacodynamics and pharmacokinetics, notably volumes of distribution and clearance, can be altered by critical illness and can influence dosing regimens. Dosing decisions in different subgroups of patients, e.g., the obese, are also covered. We also briefly consider ventilator-associated pneumonia and the role of inhaled antibiotics. Finally, we mention antibiotics that are currently being developed and show promise for the future.

Implementing an Antibiotic Stewardship Program: Guidelines by the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America

Evidence-based guidelines for implementation and measurement of antibiotic stewardship interventions in inpatient populations including long-term care were prepared by a multidisciplinary expert panel of the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America. The panel included clinicians and investigators representing internal medicine, emergency medicine, microbiology, critical care, surgery, epidemiology, pharmacy, and adult and pediatric infectious diseases specialties. These recommendations address the best approaches for antibiotic stewardship programs to influence the optimal use of antibiotics.