The effect of Surgical Care Improvement Project measures on national trends on surgical site infections in open vascular procedures

The sac evolution imaging follow-up after endovascular aortic repair: An international expert opinion-based Delphi consensus study

OBJECTIVE

Management of follow-up protocols after endovascular aortic repair (EVAR) varies significantly between centers and is not standardized according to sac regression. By designing an international expert-based Delphi consensus, the study aimed to create recommendations on follow-up after EVAR according to sac evolution.

METHODS

Eight facilitators created appropriate statements regarding the study topic that were voted, using a 4-point Likert scale, by a selected panel of international experts using a three-round modified Delphi consensus process. Based on the experts' responses, only those statements reaching a grade A (full agreement ≥75%) or B (overall agreement ≥80% and full disagreement <5%) were included in the final document.

RESULTS

One-hundred and seventy-four participants were included in the final analysis, and each voted the initial 29 statements related to the definition of sac regression (Q1-Q9), EVAR follow-up (Q10-Q14), and the assessment and role of sac regression during follow-up (Q15-Q29). At the end of the process, 2 statements (6.9%) were rejected, 9 statements (31%) received a grade B consensus strength, and 18 (62.1%) reached a grade A consensus strength. Of 27 final statements, 15 (55.6%) were classified as grade I, whereas 12 (44.4%) were classified as grade II. Experts agreed that sac regression should be considered an important indicator of EVAR success and always be assessed during follow-up after EVAR.

CONCLUSIONS

Based on the elevated strength and high consistency of this international expert-based Delphi consensus, most of the statements might guide the current clinical management of follow-up after EVAR according to the sac regression. Future studies are needed to clarify debated issues.

Effectiveness of negative-pressure wound therapy to standard therapy in the prevention of complications after vascular surgery

Wound complications are common after vascular surgery and many may be preventable. Negative pressure wound therapy (NPWT) dressings may be able to reduce wound complications relating to closed incisions following vascular surgery and several devices are currently available along with a large body of literature. This review article will describe the use of NPWT dressings in vascular surgery. We will summarize the currently available systems, the likely mechanism of action of NWPT, the published studies to date and we will give our recommendations regarding the priorities for future research on this topic.

Impact of closed-incision negative pressure wound dressings on surgical site infection following groin incisions in vascular surgery; a single-centre experience

OBJECTIVES

Surgical site infection (SSI) is a common complication in vascular surgery, and is associated with increased patient morbidity, readmission and reintervention. The aim of this study was to assess the impact of closed-incision negative pressure wound therapy (CiNPWT) upon rate of SSI and length of hospital stay.

METHODS

This study was reported in line with the STROBE guidelines. We assessed the baseline incidence of SSI from a 12-month retrospective cohort and, following a change in practice intervention with CiNPWT, compared to a 6-month prospective cohort. The primary endpoint was incidence of SSI (according to CDC-NHSN guidelines) while secondary endpoints included length of hospital stay, readmission, reintervention and Days Alive and Out of Hospital (DAOH) to 90-days.

RESULTS

A total of 127 groin incisions were performed: 76 (65 patients) within the retrospective analysis and 51 (42 patients) within the prospective analysis (of whom 69% received CiNPWT). The primary endpoint of SSI was seen in 21.1% of the retrospective cohort and 9.8% of the prospective cohort (p = .099). Readmission was found to be significantly associated with the retrospective cohort (p = .016) while total admission (inclusive of re-admission) was significantly longer in those in the retrospective cohort (p = .013). DAOH-90 was 83 days (77-85) following introduction of the CiNPWT protocol as compared to the retrospective cohort (77 days (64-83), p = .04).

CONCLUSION

Introduction of CiNPWT was associated with a reduced length of hospital stay and improved DAOH-90. Further trials on CINPWT should include patient-centred outcomes and healthcare cost analysis.

Perioperative care bundles for the prevention of surgical-site infections: meta-analysis

BACKGROUND

Care bundles are used widely to prevent surgical-site infections (SSIs). Recent systematic reviews suggested larger effects from bundles with more interventions. These reviews were largely based on uncontrolled before-after studies and did not consider their biases. The aim of this meta-analysis was to determine the effectiveness of care bundles to prevent SSIs and explore characteristics of effective care bundles.

METHODS

A systematic review, reanalysis, and meta-analysis of available evidence were undertaken. RCTs, controlled before-after studies, and uncontrolled before-after studies with sufficient data for reanalysis as interrupted time series studies (ITS) were eligible. Studies investigating the use of a care bundle, with at least one intraoperative intervention, compared with standard care were included.

RESULTS

Four RCTs, 1 controlled before-after study, and 13 ITS were included. Pooled data from RCTs were heterogeneous. Meta-analysis of ITS resulted in a level change of -1.16 (95 per cent c.i.-1.78 to -0.53), indicating a reduction in SSI. The effect was larger when the care bundle comprised a higher proportion of evidence-based interventions. Meta-regression analyses did not show statistically significant associations between effect estimates and number of interventions, number of evidence-based interventions, or proportion of evidence-based interventions.

CONCLUSION

Meta-analysis of ITS indicated that perioperative care bundles prevent SSI.This effect is inconsistent across RCTs. Larger bundles were not associated with a larger effect, but the effect may be larger if the care bundle contains a high proportion of evidence-based interventions. No strong evidence for characteristics of effective care bundles was identified.

Meta-analysis of prophylactic closed-incision negative pressure wound therapy for vascular surgery groin wounds

OBJECTIVE

Previous meta-analysis of randomized control trials evaluating the efficacy of closed incision negative pressure wound therapy (ciNPWT) on vascular surgery groin wounds reported a reduction in surgical site infections (SSI). Our aim was to perform a comprehensive, updated meta-analysis after the largest multicenter randomized control trial (RCT) on the subject to date reported no benefit of ciNPWT.

METHODS

A systematic review identified RCTs that compared the primary outcome of incidence of postoperative SSIs of groin incisions treated with ciNPWT or standard dressings. Secondary outcomes included wound dehiscence, composite incidence of seroma / lymph leak / hematoma, need for reoperation, in-hospital mortality, need for readmission and hospital length of stay. Odds ratios were compared across studies using random effects meta-analysis. Risk of bias was assessed using the Cochrane Risk of Bias tool, Harbord test and trim-and-fill analysis.

RESULTS

Eight RCTs comprised of 1125 incisions (n = 555 [49.3%] ciNPT, n = 570 [50.7%] control) were included. RCTs included 3 studies inside and 5 outside of the United States. ciNPWT was associated with a significant reduction in rate of SSIs (OR 0.39; 95% CI 0.24-0.63; p < 0.001). There was no significant difference in rate of wound dehiscence (OR 1.11, 95% CI 0.67-1.83, p = 0.68), composite incidence of seroma, lymph leak or hematoma (OR 0.49, 95% CI 0.13-1.76, p= 0.27), need for reoperation (OR 0.68, 95% CI 0.40-1.16, p = 0.16), or need for readmission (OR 0.60, 95% CI 0.30-1.21, p = 0.15). It was not possible to quantitatively evaluate in-hospital mortality or hospital length of stay. Risk of bias assessment identified high risk of bias regarding participant blinding in all studies, low risk in randomization and outcome reporting, and variability between studies in other methodologies. There was no evidence of publication bias.

CONCLUSIONS

Meta-analysis of pooled data suggest prophylactic use of ciNPWT for vascular groin incisions is associated with reduced rates of SSIs, with the greatest benefits seen in trials with higher baseline rates of infection in the control group.

Clinical Relevance of Closed-Incision Negative Pressure Therapy (ciNPT) for SSI-Risk Reduction in Vascular Surgery Through a Groin Incision

BACKGROUND

Vascular surgery, especially lower limb revascularization surgery, has one of the highest rates of surgical complications, predominantly surgical site infections (SSI). Resulting in a significant burden of additional costs due to longer hospital stays, re-admissions and re-interventions, mainly attributable to deep incisional SSIs. Closed incisional negative pressure therapy (ciNPT) is a relatively new strategy in the postoperative management surgical wounds, aiming to reduce surgical wound complications. When discussing the clinical relevance of ciNPT, it is crucial to take into account the outcome of therapy as well as the additional costs related to ciNPT. Since, the additional costs must be justified by an associated decrease in the morbidity and costs associated with groin wound complications, which are particularly attributable to deep incisional SSIs. The current literature evaluating the beneficial effect of ciNPT in groin incisional vascular surgery, predominantly focusses on the decrease in superficial SSIs. Whereas this study aims to address and discuss the clinical relevance of ciNPT over conventional wound dressings, by separately evaluating and comparing the incidence of superficial and deep SSIs and their related re-admissions and re-interventions.

METHODS

In this single center prospective cohort study performed in a non-academic hospital in The Netherlands, 59 consecutive patients (67 incisions) were included between January and October 2019. All underwent elective vascular surgery with groin (access) incisions for either lower limb revascularization surgery or abdominal aortic aneurysm surgery. The study group was treated with six days ciNPT (PREVENA Incision Management System; KCI/3M, San Antonio, TX, USA) and matched for equal comparison to a historical retrospectively analysed cohort of 54 consecutive patients (60 incisions), all of whom have undergone elective vascular surgery for equal indications with groin (access) incisions in our center between January and October 2018. The standard-care group was treated following standard surgical wound care protocol with conventional surgical self-adhesive plaster (10 × 15cm, Mepore, Mölnlycke Health Care AB, Gothenburg, Sweden).

RESULTS

Study groups were comparable at baseline, except for Body Mass Index (BMI), which was significantly higher in the ciNPT-group (P =.021). No significant differences for formation of seroma, hematoma, as well as wound dehiscence and SSIs were found between both groups. Groin SSIs were seen in 12.1% of the patients in the ciNPT-group and in 13.0% in the Standard-care group (OR 0.80, CI ((0.26, 2.48)), deep SSI contributed for 4 out of 7 patients of total SSIs in the ciNPT-group and for 2 out of 7 patients in the standard of care group (P-value >0.05). Analysis for incidence of hospital re-admission and re-intervention in both study groups showed no significant difference. Subset analysis in both study groups for SSIs differentiated in superficial and deep SSIs showed that only deep SSIs resulted in re-interventions.

CONCLUSIONS

Based on the findings in the population of our single center study, we conclude that routine use of ciNPT was not effective in reducing groin wound complications, and therefore could not replicate the promising findings from some previous studies. Furthermore, we did not find a reduction in the incidence of deep SSIs, which comprise the highest morbidity and costs. Considering our findings as well as the associated additional expenses related to ciNPT, it might be superfluous at this stage to use ciNPT as the new standard of post-operative groin incision care for all lower limb revascularization and abdominal aortic aneurysm surgeries. In our opinion further research is warranted for establishing a risk-factor based model for determination of the indication of ciNPT. To be able to achieve a more substantiated decision for utilizing ciNPT compared to standard surgical wound care in groin incisional vascular surgical interventions.

How to Prevent Surgical Site Infection in Vascular Surgery: A Review of the Evidence

BACKGROUND

This review aims to identify and review the current evidence for preventing postoperative surgical site infections in abdominal aortic aneurysm surgery or infrainguinal arterial surgery.

METHODS

Extended literature review of clinical trials that examined the prevention of postoperative surgical site infections in abdominal aortic aneurysm or infrainguinal arterial surgery. Searches were conducted on Ovid MEDLINE (1950 - 13 March 2020) using key terms for vascular surgery, surgical site infections and specific preventative techniques. Articles were included if they discussed a relationship between a preventative technique and surgical site infections in abdominal aortic aneurysm or infrainguinal arterial surgery. The GRADE guidelines were used to assess the quality of evidence.

RESULTS

21 techniques and 81 studies were included. Prophylactic antibiotics and negative pressure wound therapy have a high quality of evidence for the prevention of surgical site infections in abdominal aortic aneurysm or infrainguinal arterial surgery. A moderate quality evidence base was identified for gentamicin containing collagen implant (confined to high surgical site infection risk centers). Currently, there is a low or very low quality of evidence to suggest a reduction in the surgical site infection rate for combination therapy, glycaemic control, Methicillin-resistant Staphylococcus aureus screening and absorbable suture. Evidence suggests no beneficial effect for nutritional supplementation, chlorhexidine bath, hair removal therapy, Staphylococcus aureus nasal eradication, cyanoacrylate microsealant, silver grafts, rifampicin bonded grafts, triclosan coated suture and postoperative wound drains. Endoscopic saphenous vein harvest may reduce surgical site infection rate (very low quality of evidence) but may lower long-term patency. Autologous vein grafts may increase surgical site infections (very low quality of evidence) but may provide better long-term patency rates in above-knee infrainguinal bypass surgery. There was no identified evidence for perioperative normothermia, electrosurgical bipolar vessel sealer or Dermabond and Tegaderm for surgical site infection prevention in vascular surgery.

CONCLUSIONS

Prophylactic antibiotics and postoperative negative pressure wound therapy are effective in the prevention of postoperative surgical site infection in abdominal aortic aneurysm or infrainguinal arterial surgery. There exists a significant risk of bias in the literature for many preventative techniques and further studies are required to investigate the efficacy of gentamicin containing collagen implant, and specific combination therapies.

Short-term outcomes of open surgical abdominal aortic aneurysm repair from the Dutch Surgical Aneurysm Audit

Background

The sharp decrease in open surgical repair (OSR) for abdominal aortic aneurysm (AAA) has raised concerns about contemporary postoperative outcomes. The study was designed to analyse the impact of complications on clinical outcomes within 30 days following OSR.

Methods

Patients who underwent OSR for intact AAA registered prospectively between 2016 and 2019 in the Dutch Surgical Aneurysm Audit were included. Complications and outcomes (death, secondary interventions, prolonged hospitalization) were evaluated. The adjusted relative risk (aRr) and 95 per cent confidence intervals were computed using Poisson regression. Subsequently, the population-attributable fraction (PAF) was calculated. The PAF reflects the expected percentage reduction of an outcome if a complication were to be completely prevented.

Results

A total of 1657 patients were analysed. Bowel ischaemia and renal complications had the largest impact on death (aRr 12·44 (95 per cent c.i. 7·95 to 19·84) at PAF 20 (95 per cent c.i. 8·4 to 31·5) per cent and aRr 5·07 (95 per cent c.i. 3·18 to 8.07) at PAF 14 (95 per cent c.i. 0·7 to 27·0) per cent, respectively). Arterial occlusion had the greatest impact on secondary interventions (aRr 11·28 (95 per cent c.i. 8·90 to 14·30) at PAF 21 (95 per cent c.i. 14·7 to 28·1) per cent), and pneumonia (aRr 2·52 (95 per cent c.i. 2·04 to 3·10) at PAF 13 (95 per cent c.i. 8·3 to 17·8) per cent) on prolonged hospitalization. Small effects were observed on outcomes for other complications.

Conclusion

The greatest clinical impact following OSR can be made by focusing on measures to reduce the occurrence of bowel ischaemia, arterial occlusion and pneumonia.

A multicenter, prospective randomized trial of negative pressure wound therapy for infrainguinal revascularization with a groin incision

BACKGROUND

Wound complications after open infrainguinal revascularization are a frequent cause of patient morbidity, resulting in increased healthcare costs. The purpose of the present study was to assess the effects of closed incision negative pressure therapy (ciNPT) on groin wound complications after infrainguinal bypass and femoral endarterectomy.

METHODS

A total of 242 patients who had undergone infrainguinal bypass (n = 124) or femoral endarterectomy (n = 118) at five academic medical centers in New England from April 2015 to August 2019 were randomized to ciNPT (PREVENA; 3M KCI, St Paul, Minn; n = 118) or standard gauze (n = 124). The primary outcome measure was a composite endpoint of groin wound complications, including surgical site infections (SSIs), major noninfectious wound complications, or graft infections within 30 days after surgery. The secondary outcome measures included 30-day SSIs, 30-day noninfectious wound complications, readmission for wound complications, significant adverse events, and health-related quality of life using the EuroQoL 5D-3L survey.

RESULTS

The ciNPT and control groups had similar demographics (age, 67 vs 67 years, P = .98; male gender, 71% vs 70%, P = .86; white race, 93% vs 93%, P = .97), comorbidities (previous or current smoking, 93% vs 94%, P = .46; diabetes, 41% vs 48%, P = .20; renal insufficiency, 4% vs 7%, P = .31), and operative characteristics, including procedure type, autogenous conduit, and operative time. No differences were found in the primary composite outcome at 30 days between the two groups (ciNPT vs control: 31% vs 28%; P = .55). The incidence of SSI at 30 days was similar between the two groups (ciNPT vs control: 11% vs 12%; P = .58). Infectious (13.9% vs 12.6%; P = .77) and noninfectious (20.9% vs 17.6%; P = .53) wound complications at 30 days were also similar for the ciNPT and control groups. Wound complications requiring readmission also similar between the two groups (ciNPT vs control: 9% vs 7%; P = .54). The significant adverse event rates were not different between the two groups (ciNPT vs control: 13% vs 16%; P = .53). The mean length of the initial hospitalization was the same for the ciNPT and control groups (5.2 vs 5.7 days; P = .63). The overall health-related quality of life was similar at baseline and at 14 and 30 days postoperatively for the two groups. Although not powered for stratification, we found no differences among the subgroups in gender, obesity, diabetes, smoking, claudication, chronic limb threatening ischemia, bypass, or endarterectomy. On multivariable analysis, no differences were found in wound complications at 30 days for the ciNPT vs gauze groups (odds ratio, 1.4; 95% confidence interval, 0.8-2.6; P = .234).

CONCLUSIONS

In contrast to other randomized studies, our multicenter trial of infrainguinal revascularization found no differences in the 30-day groin wound complications for patients treated with ciNPT vs standard gauze dressings. However, the SSI rate was lower in the control group than reported in other studies, suggesting other practice patterns and processes of care might have reduced the rate of groin infections. Further study might identify the subsets of high-risk patients that could benefit from ciNPT.

National trends in postoperative infections across surgical specialties

BACKGROUND

Despite the introduction of several measures to reduce incidence, postoperative infections have been reported to increase. We aimed to assess trends in the incidence and impact of postoperative infections using a recent national cohort.

METHODS

Patients undergoing the most commonly performed elective inpatient procedures in 9 surgical specialties were identified from the 2006 to 2014 National Inpatient Sample. Diagnostic coding was utilized to identify patients with postoperative infections. To adjust for patient and operative differences in assessing outcomes, an inverse probability of treatment weighing protocol was used.

RESULTS

Of an estimated 23,696,588 patients, 1,213,182 (5.1%) developed postoperative infections. Skin and soft tissue operations had the highest burden (12.9%) and endocrine the lowest (1.3%). During the study period, we found decreasing incidence, case fatality, and incremental cost of postoperative infections. Infection was associated with increased in-hospital mortality (1.4 vs 0.4%, P < .001), duration of stay (7.6 vs 3.7 days, P < .001), and costs ($27,597 vs $17,985, P < .001). Annually, postoperative infections led to an average incremental cost burden exceeding $700 million in the United States alone.

CONCLUSION

During the study period there was a substantial decrease in the burden of postoperative infections. Despite encouraging trends, postoperative infections continue to serve as a suitable quality improvement target, particularly in specialties with a high burden of infections.

Outcomes in Ambulatory Anesthesia: Measuring What Matters

Health care professionals see measurement through their own eyes and biases. This article makes the patient central to what is measured. Patient-reported experience measures and patient-reported outcome measures are of the utmost importance. In addition, as clinicians continue to evolve how they measure what really matters, they need to be mindful of the time taken from direct patient care to achieve these activities. In addition, and most important, clinicians must ensure that all measures are designed to ensure that population health is improved, that patient experience and outcomes are enhanced, and that the cost of care is reduced.

The evaluation of the implementation of the vascular preventative bundle and development of suggested interventions for improvement and sustainability

Postoperative infections can complicate patient care and increase health care costs. A vascular preventative bundle was implemented at a large teaching/research intensive hospital to decrease surgical site infections (SSIs) with vascular surgery patients. The aim of this study was to measure fidelity to the bundle and determine if implementation of the vascular SSI bundle reduced the rate of SSIs. Three periods of data were collected, and they are identified as preimplementation (period 1), early implementation (period 2), and postimplementation (period 3). There were 711 patients for all three periods, approximately equally distributed in the periods. The use of preoperative hair clippings, chlorhexidine (CHG) wipes, and appropriate antibiotics showed the greatest improvement from preimplementation to early implementation. All three measures showed significant improvements in fidelity. For appropriate antibiotics, the fidelity was the highest and showed the largest improvement compared to the other measures. The performance of clippings preoperatively and using CHG wipes improved significantly. Evidence-based interventions have been recommended to support the implementation and sustainability of the bundle. The infection rate between preop and postperiod was not statistically different.

Quality improvement initiative: Preventative Surgical Site Infection Protocol in Vascular Surgery

Objective

A quality improvement initiative was employed to decrease single institution surgical site infection rate in open lower extremity revascularization procedures. Summary background data: In an attempt to lower patient morbidity, we developed and implemented the Preventative Surgical Site Infection Protocol in Vascular Surgery. Surgical site infections lead to prolonged hospital stays, adjunctive procedure, and additive costs. We employed targeted interventions to address the common risk factors that predispose patients to post-operative complications.

Methods

Retrospective review was performed between 2012 and 2016 for all surgical site infections after revascularization procedures of the lower extremity. A quality improvement protocol was initiated in January 2015. Primary outcome was the assessment of surgical site infection rate reduction in the pre-protocol vs. post-protocol era. Secondary outcomes evaluated patient demographics, closure method, perioperative antibiotic coverage, and management outcomes.

Results

Implementation of the protocol decreased the surgical site infection rate from 6.4% to 1.6% p = 0.0137). Patient demographics and comorbidities were assessed and failed to demonstrate a statistically significant difference among the infection and no-infection groups. Wound closure with monocryl suture vs. staple proved to be associated with decreased surgical site infection rate ( p < 0.005).

Conclusions

Preventative measures, in the form of a standardized protocol, to decrease surgical site infections in the vascular surgery population are effective and necessary. Our data suggest that there may be benefit in the incorporation of MRSA and Gram-negative coverage as part of the Surgical Care Improvement Project perioperative guidelines.

Perioperative Infections after Open Abdominal Aortic Aneurysm Repair Lead to Increased Risk of Subsequent Complications

BACKGROUND

Patients undergoing open abdominal aortic aneurysm (AAA) repair are at risk of perioperative infections that can lead to subsequent complications. Our goal was to understand how an initial infectious complication influences the risk of subsequent complications in this cohort of patients.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2005-2012), we evaluated the relationship between 3 index infectious complications after open elective AAA repair (pneumonia, deep/organ surgical site infection [SSI], and urinary tract infection [UTI]) and subsequent complications. We used 5:1 propensity matching and calculated propensity score to experience to establish matching cohorts for each index complication. This score was based on preoperative variables and number of event-free days.

RESULTS

There were 3,991 patients who were identified to have undergone elective open AAA repair in the ACS-NSQIP database. Postoperative index pneumonia was associated with increased risk of unplanned intubation (28.6% vs. 3.5%; odds ratio [OR], 10.9; 95% confidence interval [CI]: 6.7-17.5; P < 0.001), prolonged ventilation (38.5% vs. 6.7%; OR, 8.7; 95% CI: 5.9-13.0; P < 0.001), sepsis (14.3% vs. 3.3%; OR, 4.8; 95% CI: 2.8-8.4; P < 0.001), acute renal failure (9.9% vs. 2.1%; OR, 5.1; 95% CI: 2.6-9.9; P < 0.001), deep vein thrombosis (DVT) (3.8% vs. 1.4%; OR, 2.7; 95% CI: 1.1-7.0; P = 0.035), and mortality (7.1% vs. 3.0%; OR, 2.5; 95% CI: 1.3-4.9; P = 0.009). Postoperative index UTI was associated with increased risk of sepsis (21.4% vs. 0%; OR, 49.2; 95% CI: 14.5-166.8; P < 0.001), pneumonia (10.7% vs. 2.9%; OR, 4.0; 95% CI: 1.8-8.6; P = 0.001), DVT (3.6% vs. 0.4%; OR, 10.0; 95% CI: 1.8-55.5; P = 0.008), and mortality (5.4% vs. 1.8%; OR, 3.0; 95% CI: 1.1-8.5; P = 0.02). Finally, postoperative index deep/organ SSI increased the risk of pneumonia (13.0% vs. 0.9%; OR, 16.7; 95% CI: 1.6-168.2; P = 0.017), prolonged ventilation (21.7% vs. 0.9%; OR, 30.8; 95% CI: 3.4-279.4; P = 0.002), and sepsis (13.0% vs. 0.9%; OR, 16.7; 95% CI: 1.6-168.2; P = 0.017).

CONCLUSIONS

A postoperative nosocomial infection after open AAA repair is significantly more likely to lead to serious subsequent complications. Prevention and early identification of infectious index complications and subsequent complications could allow for interventions that could decrease morbidity and mortality.

Interventions to improve antibiotic prescribing practices for hospital inpatients

BACKGROUND

Antibiotic resistance is a major public health problem. Infections caused by multidrug-resistant bacteria are associated with prolonged hospital stay and death compared with infections caused by susceptible bacteria. Appropriate antibiotic use in hospitals should ensure effective treatment of patients with infection and reduce unnecessary prescriptions. We updated this systematic review to evaluate the impact of interventions to improve antibiotic prescribing to hospital inpatients.

OBJECTIVES

To estimate the effectiveness and safety of interventions to improve antibiotic prescribing to hospital inpatients and to investigate the effect of two intervention functions: restriction and enablement.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library), MEDLINE, and Embase. We searched for additional studies using the bibliographies of included articles and personal files. The last search from which records were evaluated and any studies identified incorporated into the review was January 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and non-randomised studies (NRS). We included three non-randomised study designs to measure behavioural and clinical outcomes and analyse variation in the effects: non- randomised trials (NRT), controlled before-after (CBA) studies and interrupted time series (ITS) studies. For this update we also included three additional NRS designs (case control, cohort, and qualitative studies) to identify unintended consequences. Interventions included any professional or structural interventions as defined by the Cochrane Effective Practice and Organisation of Care Group. We defined restriction as 'using rules to reduce the opportunity to engage in the target behaviour (or increase the target behaviour by reducing the opportunity to engage in competing behaviours)'. We defined enablement as 'increasing means/reducing barriers to increase capability or opportunity'. The main comparison was between intervention and no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and assessed study risk of bias. We performed meta-analysis and meta-regression of RCTs and meta-regression of ITS studies. We classified behaviour change functions for all interventions in the review, including those studies in the previously published versions. We analysed dichotomous data with a risk difference (RD). We assessed certainty of evidence with GRADE criteria.

MAIN RESULTS

This review includes 221 studies (58 RCTs, and 163 NRS). Most studies were from North America (96) or Europe (87). The remaining studies were from Asia (19), South America (8), Australia (8), and the East Asia (3). Although 62% of RCTs were at a high risk of bias, the results for the main review outcomes were similar when we restricted the analysis to studies at low risk of bias.More hospital inpatients were treated according to antibiotic prescribing policy with the intervention compared with no intervention based on 29 RCTs of predominantly enablement interventions (RD 15%, 95% confidence interval (CI) 14% to 16%; 23,394 participants; high-certainty evidence). This represents an increase from 43% to 58% .There were high levels of heterogeneity of effect size but the direction consistently favoured intervention.The duration of antibiotic treatment decreased by 1.95 days (95% CI 2.22 to 1.67; 14 RCTs; 3318 participants; high-certainty evidence) from 11.0 days. Information from non-randomised studies showed interventions to be associated with improvement in prescribing according to antibiotic policy in routine clinical practice, with 70% of interventions being hospital-wide compared with 31% for RCTs. The risk of death was similar between intervention and control groups (11% in both arms), indicating that antibiotic use can likely be reduced without adversely affecting mortality (RD 0%, 95% CI -1% to 0%; 28 RCTs; 15,827 participants; moderate-certainty evidence). Antibiotic stewardship interventions probably reduce length of stay by 1.12 days (95% CI 0.7 to 1.54 days; 15 RCTs; 3834 participants; moderate-certainty evidence). One RCT and six NRS raised concerns that restrictive interventions may lead to delay in treatment and negative professional culture because of breakdown in communication and trust between infection specialists and clinical teams (low-certainty evidence).Both enablement and restriction were independently associated with increased compliance with antibiotic policies, and enablement enhanced the effect of restrictive interventions (high-certainty evidence). Enabling interventions that included feedback were probably more effective than those that did not (moderate-certainty evidence).There was very low-certainty evidence about the effect of the interventions on reducing Clostridium difficile infections (median -48.6%, interquartile range -80.7% to -19.2%; 7 studies). This was also the case for resistant gram-negative bacteria (median -12.9%, interquartile range -35.3% to 25.2%; 11 studies) and resistant gram-positive bacteria (median -19.3%, interquartile range -50.1% to +23.1%; 9 studies). There was too much variance in microbial outcomes to reliably assess the effect of change in antibiotic use. Heterogeneity of intervention effect on prescribing outcomesWe analysed effect modifiers in 29 RCTs and 91 ITS studies. Enablement and restriction were independently associated with a larger effect size (high-certainty evidence). Feedback was included in 4 (17%) of 23 RCTs and 20 (47%) of 43 ITS studies of enabling interventions and was associated with greater intervention effect. Enablement was included in 13 (45%) of 29 ITS studies with restrictive interventions and enhanced intervention effect.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that interventions are effective in increasing compliance with antibiotic policy and reducing duration of antibiotic treatment. Lower use of antibiotics probably does not increase mortality and likely reduces length of stay. Additional trials comparing antibiotic stewardship with no intervention are unlikely to change our conclusions. Enablement consistently increased the effect of interventions, including those with a restrictive component. Although feedback further increased intervention effect, it was used in only a minority of enabling interventions. Interventions were successful in safely reducing unnecessary antibiotic use in hospitals, despite the fact that the majority did not use the most effective behaviour change techniques. Consequently, effective dissemination of our findings could have considerable health service and policy impact. Future research should instead focus on targeting treatment and assessing other measures of patient safety, assess different stewardship interventions, and explore the barriers and facilitators to implementation. More research is required on unintended consequences of restrictive interventions.

Rate of Organ Space Infection Is Reduced with the Use of an Air Leak Test During Major Hepatectomies

BACKGROUND

Organ/space surgical site infections (OSIs) constitute an important postoperative metric. We sought to assess the impact of a previously described air leak test (ALT) on the incidence of OSI following major hepatectomies.

METHODS

A single-institution hepatobiliary database was queried for patients who underwent a major hepatectomy without biliary-enteric anastomosis between January 2009 and June 2015. Demographic, clinicopathologic, and intraoperative data-including application of ALT-were analyzed for associations with postoperative outcomes, including OSI, hospital length of stay (LOS), morbidity and mortality rates, and readmission rates.

RESULTS

Three hundred eighteen patients were identified who met inclusion criteria, of whom 210 had an ALT. ALT and non-ALT patients did not differ in most disease and treatment characteristics, except for higher rates of trisegmentectomy among ALT patients (53 vs. 34 %, p = 0.002). ALT patients experienced lower rates of OSI and 90-day morbidity than non-ALT patients (5.2 vs. 13.0 %, p = 0.015 and 24.8 vs. 40.7 %, p = 0.003, respectively). In turn, OSI was the strongest independent predictor of longer LOS (OR = 4.89; 95 % CI, 2.80-6.97) and higher rates of 30- (OR = 32.0; 95 % CI, 10.9-93.8) and 45-day readmissions (OR = 29.4; 95 % CI, 10.2-84.6).

CONCLUSIONS

The use of an intraoperative ALT significantly reduces the rate of OSI following major hepatectomy and may contribute to lower post-discharge readmission rates.

Preoperative risk prediction of surgical site infection requiring hospitalization or reoperation in patients undergoing vascular surgery

OBJECTIVE

The objective of this study was to develop a surgical site infection (SSI) prediction score for risk assessment before elective vascular surgery.

METHODS

We conducted a nested case-control study among patients who underwent elective vascular (abdominal aortic and peripheral arterial) surgery from January 1, 2003, to December 31, 2007, at Mayo Clinic (Rochester, Minn) an academic tertiary surgical center. Cases were patients with SSI requiring hospitalization; controls (one or two per case) were matched on type of procedure and date of surgery. Clinical data were collected by chart review. A risk score based on preoperative variables was developed using multivariable logistic regression and bootstrap resampling. The C statistic, equivalent to the area under the receiver operating characteristic curve, was used to assess discrimination. Calibration was assessed by plotting percentile risk groups of model-predicted values against observed proportions of subjects with SSI.

RESULTS

Eighty-four cases were compared with 160 controls. Preoperative variables independently associated with SSI risk were critical limb ischemia, previous SSI, prior revascularization procedure, and chronic obstructive pulmonary disease. A prediction model containing these variables was developed (model and risk score C statistic of 0.737 and 0.727, respectively). The calibration curve did not appear to deviate appreciably from the 45-degree line of identity.

CONCLUSIONS

We developed an SSI risk score based on noninvasive preoperative variables with acceptable discrimination and calibration. This tool needs prospective and external validation.

Diagnosis and Treatment of Vascular Surgery Related Infection

Surgical site infection (SSI) is an important component of infections acquired from hospital. The most significant feature of vascular surgery different from other surgeries is frequent application of artificial grafts. Once SSI occurs after vascular operations with grafts, it might results in a serious disaster. Staphylococcus aureus and coagulase-negative Staphylococcus are the most common pathogenic bacteria for SSI after vascular surgery. Although SSI in vascular surgery often lacks of typical clinical characters, some clinical symptoms, laboratory data and certain imaging procedures may help to diagnose. In most cases of SSI after vascular procedures, the artificial grafts must be removed and sensitive antibiotics should be administered. However, for different cases, personalized management plan should be made depending on the severity and location of SSI.

Interventions to improve antibiotic prescribing practices for hospital inpatients

BACKGROUND

The first publication of this review in Issue 3, 2005 included studies up to November 2003. This update adds studies to December 2006 and focuses on application of a new method for meta-analysis of interrupted time series studies and application of new Cochrane Effective Practice and Organisation of Care (EPOC) Risk of Bias criteria to all studies in the review, including those studies in the previously published version. The aim of the review is to evaluate the impact of interventions from the perspective of antibiotic stewardship. The two objectives of antibiotic stewardship are first to ensure effective treatment for patients with bacterial infection and second support professionals and patients to reduce unnecessary use and minimize collateral damage.

OBJECTIVES

To estimate the effectiveness of professional interventions that, alone or in combination, are effective in antibiotic stewardship for hospital inpatients, to evaluate the impact of these interventions on reducing the incidence of antimicrobial-resistant pathogens or Clostridium difficile infection and their impact on clinical outcome.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE from 1980 to December 2006 and the EPOC specialized register in July 2007 and February 2009 and bibliographies of retrieved articles. The main comparison is between interventions that had a restrictive element and those that were purely persuasive. Restrictive interventions were implemented through restriction of the freedom of prescribers to select some antibiotics. Persuasive interventions used one or more of the following methods for changing professional behaviour: dissemination of educational resources, reminders, audit and feedback, or educational outreach. Restrictive interventions could contain persuasive elements.

SELECTION CRITERIA

We included randomized clinical trials (RCTs), controlled clinical trials (CCT), controlled before-after (CBA) and interrupted time series studies (ITS). Interventions included any professional or structural interventions as defined by EPOC. The intervention had to include a component that aimed to improve antibiotic prescribing to hospital inpatients, either by increasing effective treatment or by reducing unnecessary treatment. The results had to include interpretable data about the effect of the intervention on antibiotic prescribing or microbial outcomes or relevant clinical outcomes.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and assessed quality. We performed meta-regression of ITS studies to compare the results of persuasive and restrictive interventions. Persuasive interventions advised physicians about how to prescribe or gave them feedback about how they prescribed. Restrictive interventions put a limit on how they prescribed; for example, physicians had to have approval from an infection specialist in order to prescribe an antibiotic. We standardized the results of some ITS studies so that they are on the same scale (percent change in outcome), thereby facilitating comparisons of different interventions. To do this, we used the change in level and change in slope to estimate the effect size with increasing time after the intervention (one month, six months, one year, etc) as the percent change in level at each time point. We did not extrapolate beyond the end of data collection after the intervention. The meta-regression was performed using standard weighted linear regression with the standard errors of the coefficients adjusted where necessary.

MAIN RESULTS

For this update we included 89 studies that reported 95 interventions. Of the 89 studies, 56 were ITSs (of which 4 were controlled ITSs), 25 were RCT (of which 5 were cluster-RCTs), 5 were CBAs and 3 were CCTs (of which 1 was a cluster-CCT).Most (80/95, 84%) of the interventions targeted the antibiotic prescribed (choice of antibiotic, timing of first dose and route of administration). The remaining 15 interventions aimed to change exposure of patients to antibiotics by targeting the decision to treat or the duration of treatment. Reliable data about impact on antibiotic prescribing data were available for 76 interventions (44 persuasive, 24 restrictive and 8 structural). For the persuasive interventions, the median change in antibiotic prescribing was 42.3% for the ITSs, 31.6% for the controlled ITSs, 17.7% for the CBAs, 3.5% for the cluster-RCTs and 24.7% for the RCTs. The restrictive interventions had a median effect size of 34.7% for the ITSs, 17.1% for the CBAs and 40.5% for the RCTs. The structural interventions had a median effect of 13.3% for the RCTs and 23.6% for the cluster-RCTs. Data about impact on microbial outcomes were available for 21 interventions but only 6 of these also had reliable data about impact on antibiotic prescribing.Meta-analysis of 52 ITS studies was used to compare restrictive versus purely persuasive interventions. Restrictive interventions had significantly greater impact on prescribing outcomes at one month (32%, 95% confidence interval (CI) 2% to 61%, P = 0.03) and on microbial outcomes at 6 months (53%, 95% CI 31% to 75%, P = 0.001) but there were no significant differences at 12 or 24 months. Interventions intended to decrease excessive prescribing were associated with reduction in Clostridium difficile infections and colonization or infection with aminoglycoside- or cephalosporin-resistant gram-negative bacteria, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis. Meta-analysis of clinical outcomes showed that four interventions intended to increase effective prescribing for pneumonia were associated with significant reduction in mortality (risk ratio 0.89, 95% CI 0.82 to 0.97), whereas nine interventions intended to decrease excessive prescribing were not associated with significant increase in mortality (risk ratio 0.92, 95% CI 0.81 to 1.06).

AUTHORS' CONCLUSIONS

The results show that interventions to reduce excessive antibiotic prescribing to hospital inpatients can reduce antimicrobial resistance or hospital-acquired infections, and interventions to increase effective prescribing can improve clinical outcome. This update provides more evidence about unintended clinical consequences of interventions and about the effect of interventions to reduce exposure of patients to antibiotics. The meta-analysis supports the use of restrictive interventions when the need is urgent, but suggests that persuasive and restrictive interventions are equally effective after six months.