Prevention of Staphylococcus aureus infections among surgical patients: Beyond traditional perioperative prophylaxis

Preoperative MRSA screening using a simple questionnaire prior elective total joint replacement

INTRODUCTION

The purpose of this study was to evaluate the management and results of our standarized protocol for preoperative identification of MRSA colonisation in patients undergoing primary total hip and knee replacement procedures.

METHODS

Following hospital protocol, between January 2016 and June 2019 37,745 patients awaiting elective joint replacement underwent a standardized questionnaire to assess the risk of MRSA infection, identifying patients requiring preoperative MRSA screening. An evaluation of the questionnaire identified effective questions for identifying infected patients. Furthermore, an analysis evaluated the impact of comorbidities or Charlson Comorbidity Index scores on positive MRSA colonization. Additionally, we evaluated the cost savings of targeted testing compared to testing all surgery patients.

RESULTS

Of the 37,745 patients, 8.057 (21.3%) were swabbed, with a total of 65 (0.81%) positive tests. From this group 27 (36.48%) who were treated were negative before surgery. Some of the questionnaire results were consistently associated with a higher chance of colonization, including hospitalization during the past year (47,7%), previous history of MRSA (44,6%), and agriculture or cattle farming related work (15,4%). By selectively testing high-risk patients identified through the questionnaire, we achieved a 79% reduction in costs compared to universal MRSA screening.

CONCLUSION

Our results suggest that the simple and standardized questionnaire is a valuable tool for preoperative screening, effectively identifying high-risk patients prone to MRSA colonisation. The risk of periprosthetic joint infection (PJI) and its associated sequelae may be reduced by this approach.

A comparison between different suture techniques in lumbar spine surgery

As a result of solicited muscles, strong friction, and tensile force on cutaneous tissue, the difference in closure procedure and management strategies and complications of surgical incision healing is a real challenge in lumbar spine surgery. We performed a retrospective study to compare different types of wound closure in lumbar spine surgery. 4383 patients were included in this study. Wound dehiscence was more common in the intracutaneous suture group than in the far- near-near-far suture group. Delayed wound healing occurred more in the far-near near-far suture group than intracutaneous suture group. Also, the far-near near-far interrupted point suture group showed a higher ratio of delayed wound healing compared with crossover suture. The superficial wound infection rate was roughly the same in all types of sutures with an average value of 0.79% with 0.81% SD. This is a preliminary study to compare different types of operative wounds showing the pros and cons related to each option.

Therapeutic applications of lysostaphin against Staphylococcus aureus

Staphylococcus aureus, an opportunistic pathogen, causes diverse community and nosocomial-acquired human infections, including folliculitis, impetigo, sepsis, septic arthritis, endocarditis, osteomyelitis, implant-associated biofilm infections and contagious mastitis in cattle. In recent days, both methicillin-sensitive and methicillin-resistant S. aureus infections have increased. Highly effective anti-staphylococcal agents are urgently required. Lysostaphin is a 27 kDa zinc metallo antimicrobial lytic enzyme that is produced by Staphylococcus simulans biovar staphylolyticus and was first discovered in the 1960s. Lysostaphin is highly active against S. aureus strains irrespective of their drug-resistant patterns with a minimum inhibitory concentration of ranges between 0·001 and 0·064 μg ml^-1 . Lysostaphin has activity against both dividing and non-dividing S. aureus cells; and can seep through the extracellular matrix to kill the biofilm embedded S. aureus. In spite of having excellent anti-staphylococcal activity, its clinical application is hindered because of its immunogenicity and reduced bio-availability. Extensive research with lysostaphin lead to the development of several engineered lysostaphin derivatives with reduced immunogenicity and increased serum half-life. Therapeutic efficacy of both native and engineered lysostaphin derivatives was studied by several research groups. This review provides an overview of the therapeutic applications of native and engineered lysostaphin derivatives developed to eradicate S. aureus infections.

Do lower respiratory tract samples contribute to the assessment of carriage of Staphylococcus aureus in patients undergoing mechanical ventilation after major heart surgery?

Colonization by Staphylococcus aureus is regularly assessed in patients undergoing major heart surgery (MHS). Despite pre-surgical decontamination attempts, a significant proportion of MHS patients remain colonized by S. aureus at the time of surgery. Nasal sampling can be improved by sampling extra-nasal areas. We evaluated whether processing lower respiratory tract (LRT) secretions enhanced the detection of S. aureus after MHS. Following a standard protocol, nasal swabs and LRT aspirates were obtained from all of the study patients at the time of surgery or in the immediate postoperative period. One swab was used for culture in the microbiology laboratory, and a second swab was used for the Xpert SA Nasal Complete assay. According to our definition of colonization (culture positive and/or PCR positive), 31 of 115 patients (26.9%) were colonized at the time of surgery. Among these, LRT samples only were positive in three patients (2.6% of the whole population and 9.7% of the carriers). The remaining 28 were either positive in the nasal sample or positive in both samples. The yield of the detection of colonization by S. aureus by including also LRT samples in patients undergoing MHS is limited and must be balanced with laboratory workload and demands on laboratory personnel. Trial registration: Clinical trials.gov NCT02640001.

Surgical Site Infections: An Update

Surgical site infections (SSIs) lead to adverse patient outcomes, including prolonged hospitalization and death. Wound contamination occurs with each incision, but proven strategies exist to decrease the risk of SSI. In particular, improved adherence to evidence-based preventative measures related to appropriate antimicrobial prophylaxis can decrease the rate of SSI. Aggressive surgical debridement and effective antimicrobial therapy are needed to optimize the treatment of SSI.

Prevention of periprosthetic joint infection: new guidelines

The World Health Organization (WHO) and the Centre for Disease Control and Prevention (CDC) recently published guidelines for the prevention of surgical site infection. The WHO guidelines, if implemented worldwide, could have an immense impact on our practices and those of the CDC have implications for healthcare policy in the United States. Our aim was to review the strategies for prevention of periprosthetic joint infection in light of these and other recent guidelines. Cite this article: Bone Joint J 2017;99-B(4 Supple B):3-10.

Prevention and Infection Management in Mechanical Circulatory Support Device Recipients

There are currently no guidelines for the management of infection and its prevention in mechanical circulatory support (MCS) device recipients. The International Society of Heart and Lung Transplantation (ISHLT) has initiated a multidisciplinary collaboration for the creation of a consensus document to guide clinicians in infection prevention and management in MCS patients. Most medical centers use local protocols that are based on expert opinion. MCS recipients are debilitated and have some immunological dysfunction. Over the years there have been technical advancements with smaller devices and drivelines with improved durability. The pulsatile devices have been replaced with newer-generation continuous-flow devices. Patient are living longer with MCSs for bridge to transplant (BTT) and destination therapy (DT). MCS centers have improved patient management by introducing standardized driveline protocols, leading to reduced infection rates among MCS recipients.

Controversies in Revision Rhinoplasty

Revision rhinoplasty is a complex operation with many variables that may influence the final esthetic and functional outcome of the procedure. Cartilage forms the structural framework of the lower two-thirds of nose and is essential for long-term support and maintenance of a patent nasal airway. The use of autologous cartilage grafting is the primary source of this material, limited by donor site quantity, quality, and harvest morbidity. Alloplastic materials, solid and injectable, are often used for augmentation purposes and may have devastating consequences. This article discusses past and current treatment concepts for various nasal deformities using available autologous grafting techniques.

Role of antiseptics in the prevention of surgical site infections

BACKGROUND

Antiseptics are chemical agents used to reduce the microbial population on the surface of the skin and are used in nearly every surgical procedure today. Despite this, there are currently no definitive guidelines on surgical preoperative antisepsis that indicate a specific regimen based on demonstration of superior efficacy.

OBJECTIVE

This review serves to examine preoperative antisepsis, including cutaneous bacteriology, preoperative hair removal, preoperative decolonization, surgical attire, and the antiseptic agents themselves.

MATERIALS AND METHODS

A review of the literature on surgical antiseptics was performed.

RESULTS

Although numerous studies have demonstrated differences in bacterial colonization rates, few well-controlled investigations have demonstrated superiority of a given regimen. The alcohol-based iodophor and chlorhexidine products seem to exhibit greater efficacy than their aqueous counterparts.

CONCLUSION

More randomized controlled trials will be needed to determine if any specific regimen is most effective. At this point in time, product usage should be based on specific attributes relating to the products, such as iodophors around the eyes and/or ears to avoid irritation and aqueous-based solutions in hair bearing areas because of concern for flammability. Ultimately, it is up to the individual surgeon to tailor the optimal antiseptic regimen for their specific scope of practice.

Nasal carriage of Staphylococcus aureus among surgeons and surgical residents: a nationwide prevalence study

BACKGROUND

Staphylococcus aureus nasal carriage is an independent risk factor for developing nosocomial infections and for developing surgical site infection (SSI) in particular. The number of post-operative nosocomial S. aureus infections can be reduced by screening patients and decolonizing nasal carriers. In addition to patients, health care workers may also be S. aureus nasal carriers. The aim of this study was to explore S. aureus nasal carriage rates among surgeons.

METHODS

Nasal swabs were collected from surgeons and surgical residents during a national surgical congress. The control group consisted of non-hospitalized patients. Staphylococcus aureus carriage was detected using selective chromogenic agars by use of a fully automated inoculator. Suspected colonies were identified further by positive catalase and slide coagulation reactions.

RESULTS

Samples were collected from 366 surgeons and surgical residents and 950 control patients. The S. aureus nasal carriage rate among surgeons and residents was significantly greater compared with the control group (45.4% versus 30.8%, odds ratio [OR] 1.86 [1.45-2.38], p<0.001). No significant difference in carriage rate was found between surgeons and residents (46.8% versus 43.3%, p=0.769) and years of experience as a surgeon was not associated with a greater carriage rate. Male gender was an independent risk factor for carriage among physicians odds ratio ([OR] 1.90 [95% confidence interval 1.19-3.01], p=0.007).

CONCLUSIONS

The nationwide rate of S. aureus nasal carriage among surgeons and surgical residents proved to be significantly greater compared with a non-hospitalized patient control group. Male gender is an independent risk factor for carriage among physicians. Future studies are needed to investigate the possible relation with nosocomial post-operative S. aureus infections.

Efficacy of skin and nasal povidone-iodine preparation against mupirocin-resistant methicillin-resistant Staphylococcus aureus and S. aureus within the anterior nares

Mupirocin decolonization of nasal Staphylococcus aureus prior to surgery decreases surgical-site infections; however, treatment requires 5 days, compliance is low, and resistance occurs. In 2010, 3M Company introduced povidone-iodine (PVP-I)-based skin and nasal antiseptic (Skin and Nasal Prep [SNP]). SNP has rapid, broad-spectrum antimicrobial activity. We tested SNP's efficacy using full-thickness tissue (porcine mucosal [PM] and human skin) explant models and human subjects. Prior to or following infection with methicillin-resistant Staphylococcus aureus (MRSA) (mupirocin sensitive and resistant), explants were treated with Betadine ophthalmic preparation (Bet), SNP, or mupirocin (Bactroban nasal ointment [BN]) or left untreated. One hour posttreatment, explants were washed with phosphate-buffered saline (PBS) plus 2% mucin. One, 6, or 12 h later, bacteria were recovered and enumerated. Alternatively, following baseline sampling, human subjects applied two consecutive applications of SNP or saline to their anterior nares. One, 6, and 12 h after application of the preparation (postprep), nasal swabs were obtained, and S. aureus was enumerated. We observed that treatment of infected PM or human skin explants with SNP resulted in >2.0 log10 CFU reduction in MRSA, regardless of mupirocin sensitivity, which was significantly different from the values for BN- and Bet-treated explants and untreated controls 1 h, 6 h, and 12 h after being washed with PBS plus mucin. Swabbing the anterior nares of human subjects with SNP significantly reduced resident S. aureus compared to saline 1, 6, and 12 h postprep. Finally, pretreatment of PM explants with SNP, followed by a mucin rinse prior to infection, completely prevented MRSA infection. We conclude that SNP may be an attractive alternative for reducing the bioburden of anterior nares prior to surgery.

Effects of fever on haemodynamic parameters in neurosurgical intensive care unit patients

OBJECTIVE

To investigate the effects of fever on the haemodynamic parameters (pulse rate, arterial oxygen saturation, systolic blood pressure, diastolic blood pressure and mean arterial blood pressure) of patients in a neurosurgical intensive care unit.

DESIGN

A prospective, repeated-measures study.

METHODS

This study was performed in the neurosurgical intensive care unit of a University Hospital in the West of Turkey. The research sample included all patients with at least two occurrences of fever in the postoperative period. Body temperature and haemodynamic parameters of patients were measured on admission, one hour before the onset of fever and during fever (peak temperature).

RESULTS

Increase of body temperature during fever episodes was followed by a significant increase in pulse rate (p = 0.001) with significant decreases in systolic blood pressure (p = 0.002) and arterial oxygen saturation (p = 0.001). Furthermore fever episodes were followed by a non-significant increase in diastolic blood pressure (p = 0.074) and a non-significant decrease in mean arterial blood pressure (p = 0.097). In this study, a degree celsius (1 °C) increase in body temperature, was associated with a decline of 4.43 mmHg in systolic blood pressure, 0.166 mmHg mean arterial blood pressure and 0.64% arterial oxygen saturation, respectively. It was also associated with an increase of 1.61 mmHg in diastolic arterial blood pressure and 7.46 beats/per minute pulse rate, respectively.

CONCLUSIONS

The findings from this research have demonstrated the effects that fever can have on haemodynamic parameters of patients in one neurosurgical intensive care unit. Hence the study highlights the importance for intensive care unit (ICU) nurses to appreciate the physiological effects of fever which have the potential to cause complications in febrile patients. Increasing knowledge about the effects of fever on haemodynamic parameters can therefore be of benefit to nurses in terms of quality and efficacy of patient care.

Surgical Site Infections in Orthopaedic Surgery Demonstrate Clones Similar to Those in Orthopaedic Staphylococcus aureus Nasal Carriers

BACKGROUND

Staphylococcus aureus is the main microbial pathogen in orthopaedic infections, and it adds considerable extra costs to the national health-care system each year. Nasal carriers of Staphylococcus aureus have an increased risk of invasive disease, including surgical site infection. The purpose of the present study was to investigate whether the Staphylococcus aureus carrier clones found in patients undergoing elective orthopaedic surgery were the same as the clones found in isolates from orthopaedic patients with Staphylococcus aureus surgical site infections.

METHODS

Patients admitted for elective orthopaedic surgery underwent nasal cultures for Staphylococcus aureus. Further, orthopaedic patients with a deep surgical site infection caused by Staphylococcus aureus were characterized using the same genotyping methods: multilocus sequence typing and staphylococcal protein A typing.

RESULTS

Multilocus sequence typing revealed a large number of genotypes in the two populations. However, 85% of nasal carriers and 90% of surgical site infection isolates could be classified into the same four multilocus sequence typing clonal complexes. The risk of Staphylococcus aureus surgical site infection in nasal carriers compared with non-carriers was 5.8 times higher (95% confidence interval, 1.5 to 23.1 times). Of the nasal carriers, 6.3% (95% confidence interval, 1.7% to 10.9% [seven of 111 patients]) developed a deep Staphylococcus aureus surgical site infection, and all but one patient had identical genotypes in the nasal and surgical site infection isolates.

CONCLUSIONS

Staphylococcus aureus isolates from nasal carriers and patients with surgical site infection clustered into the same few multilocus sequence typing clonal complexes. This finding confirms the existence of some commonly occurring Staphylococcus aureus clones in different population groups within a geographically restricted area. The almost complete individual concordance between Staphylococcus aureus genotypes in carriers who developed a deep surgical site infection strongly supports transmission from the nose, skin surfaces, and other endogenous body regions as a possible route.

CLINICAL RELEVANCE

Surgical site infections might be more frequently caused by endogenous transmission than was previously assumed. Perioperative preventive efforts must focus more on this route to further decrease the risk of postoperative orthopaedic infections.

Antibiotic prophylaxis in craniotomy: a review

The effectiveness of antibiotic prophylaxis (AP) in craniotomies has been clarified through the accumulation of evidence and increased antibiotic knowledge. This paper focuses on the use of AP in craniotomies during different historical periods and collects highly relevant evidence on this issue. This review surveys different AP guidelines and explains why cefazolin was selected by most guidelines. Recent prominent topics, including strategies to update and implement guidelines and antibiotic efficacy in postoperative meningitis and surveillance and decolonization therapies for methicillin-resistant Staphylococcus aureus, are discussed.

Nasal carriage of 200 patients with nasal bone fracture in Korea

Background

Pathogens in the nasal cavity during nasal surgery could lead to a systemic infectious condition, such as bacteremia, nosocomial infection, or toxic shock syndrome. However, there is no research about the prevalence of nasal carriage in patients with nasal bone fracture.

Methods

This was a prospective, double-blind, randomized study about the rate of nasal carriage in 200 patients with nasal bone fracture in Korea. Nasal secretions were taken from both the middle nasal meatus and colonized. All analyses were carried out using SPSS software.

Results

Pathogens were identified in 178 of the 200 cases. Coagulase-negative staphylococci (CNS) were the most cultured bacteria in 127 (66.84%) of the 190 total patients after excluding 10 cases of contaminated samples, and methicillin-resistant coagulase-negative staphylococci (MRCNS) were found in 48 (25.26%). Staphylococcus aureus was the second most identified pathogen, found in 36 (18.95%), followed by 7 cases (3.68%) of methicillin-resistant Staphylococcus aureus (MRSA). The prevalence rate of MRSA in the females was higher than that in the males (RR=4.70; 95% CI, 1.09-20.18), but other demographic factors had no effect on the prevalence rate of MRSA and MRCNS.

Conclusions

The prevalence rate of these pathogens in patients with nasal bone fracture in Korea was similar to other reports. However, few studies have addressed the prevalence rate of CNS and MRCNS in accordance with risk factors or the change in prevalence according to specific prophylaxis against infectious complications. Additional research is needed on the potential connections between clinical factors and microbiological data.

Effects of small intestinal submucosa (SIS) on the murine innate immune microenvironment induced by heat-killed Staphylococcus aureus

The use of biological scaffold materials for wound healing and tissue remodeling has profoundly impacted regenerative medicine and tissue engineering. The porcine-derived small intestinal submucosa (SIS) is a licensed bioscaffold material regularly used in wound and tissue repair, often in contaminated surgical fields. Complications and failures due to infection of this biomaterial have therefore been a major concern and challenge. SIS can be colonized and infected by wound-associated bacteria, particularly Staphylococcus aureus. In order to address this concern and develop novel intervention strategies, the immune microenvironment orchestrated by the combined action of S. aureus and SIS should be critically evaluated. Since the outcome of tissue remodeling is largely controlled by the local immune microenvironment, we assessed the innate immune profile in terms of cytokine/chemokine microenvironment and inflammasome-responsive genes. BALB/c mice were injected intra-peritoneally with heat-killed S. aureus in the presence or absence of SIS. Analyses of cytokines, chemokines and microarray profiling of inflammasome-related genes were done using peritoneal lavages collected 24 hours after injection. Results showed that unlike SIS, the S. aureus-SIS interactome was characterized by a Th1-biased immune profile with increased expressions of IFN-γ, IL-12 and decreased expressions of IL-4, IL-13, IL-33 and IL-6. Such modulation of the Th1/Th2 axis can greatly facilitate graft rejections. The S. aureus-SIS exposure also augmented the expressions of pro-inflammatory cytokines like IL-1β, Tnf-α, CD30L, Eotaxin and Fractalkine. This heightened inflammatory response caused by S. aureus contamination could enormously affect the biocompatibility of SIS. However, the mRNA expressions of many inflammasome-related genes like Nlrp3, Aim2, Card6 and Pycard were down-regulated by heat-killed S. aureus with or without SIS. In summary, our study explored the innate immune microenvironment induced by the combined exposure of SIS and S. aureus. These results have practical implications in developing strategies to contain infection and promote successful tissue repair.

Preoperative screening/decolonization for Staphylococcus aureus to prevent orthopedic surgical site infection: prospective cohort study with 2-year follow-up

We quantified surgical site infections (SSIs) after preoperative screening/selective decolonization before elective total joint arthroplasty (TJA) with 2-year follow-up and 2 controls. Concurrent controls (n = 2284) were patients of surgeons not participating in screening/decolonization. Preintervention controls (n = 741) were patients of participating surgeons who underwent TJA the previous year. Staphylococcus aureus nasal carriers (321/1285 [25%]) used intranasal mupirocin and chlorhexidine baths as outpatients. Staphylococcal SSIs occurred in no intervention patients (0/321) and 19 concurrent controls. If all SSIs occurred in carriers and 25% of controls were carriers, staphylococcal SSI rate would have been 3.3% in controls (19/571; P = .001). Overall SSI rate decreased from 2.7% (20/741) in preintervention controls to 1.2% (17/1440) in intervention patients (P = .009). Preoperative screening/selective decolonization was associated with fewer SSIs after elective TJA.

The economic effect of screening orthopedic surgery patients preoperatively for methicillin-resistant Staphylococcus aureus

BACKGROUND AND OBJECTIVE

Patients undergoing orthopedic surgery are susceptible to methicillin-resistant Staphylococcus aureus (MRSA) infections, which can result in increased morbidity, hospital lengths of stay, and medical costs. We sought to estimate the economic value of routine preoperative MRSA screening and decolonization of orthopedic surgery patients.

METHODS

A stochastic decision-analytic computer simulation model was used to evaluate the economic value of implementing this strategy (compared with no preoperative screening or decolonization) among orthopedic surgery patients from both the third-party payer and hospital perspectives. Sensitivity analyses explored the effects of varying MRSA colonization prevalence, the cost of screening and decolonization, and the probability of decolonization success.

RESULTS

Preoperative MRSA screening and decolonization was strongly cost-effective (incremental cost-effectiveness ratio less than $6,000 per quality-adjusted life year) from the third-party payer perspective even when MRSA prevalence was as low as 1%, decolonization success was as low as 25%, and decolonization costs were as high as $300 per patient. In most scenarios this strategy was economically dominant (ie, less costly and more effective than no screening). From the hospital perspective, preoperative MRSA screening and decolonization was the economically dominant strategy for all scenarios explored.

CONCLUSIONS

Routine preoperative screening and decolonization of orthopedic surgery patients may under many circumstances save hospitals and third-party payers money while providing health benefits.

Methicillin-resistant Staphylococcus aureus infection in septorhinoplasty

OBJECTIVES

Review the literature on methicillin-resistant Staphylococcus aureus (MRSA) infection following septorhinoplasty, identify patient groups at risk for MRSA complications following septorhinoplasty, and evaluate the need for antibiotic prophylaxis in these patients.

DISCUSSION

Patients who are susceptible to MRSA infections may also be at higher risk for nasal colonization, and this includes elderly patients, patients recently hospitalized or treated in a rehabilitation center, and healthcare workers. Few cases of MRSA infection following septorhinoplasty have been reported in the literature. Prevention of nosocomial and postsurgical MRSA infections has been well studied, and it seems that elimination of nasal colonization is a major step in preventing these infections.

CONCLUSIONS

Patients at increased risk for MRSA colonization should be screened prior to septorhinoplasty and if positive treated with antibiotic prophylaxis consisting of elimination of nasal carriage prior to surgery. Perioperative systemic antibiotic use should be considered, especially in revision cases.

Antibacterial prophylaxis in dermatologic surgery: an evidence-based review

Clean, non-contaminated skin surgery is associated with low rates of surgical site infection (SSI), bacterial endocarditis, and joint prosthesis infection. Hence, antibacterial prophylaxis, which may be associated with adverse effects, the emergence of multidrug-resistant pathogens, and anaphylaxis, is generally not recommended in dermatologic surgery. Some body sites and surgical reconstructive procedures are associated with higher infection rates, and guidelines for SSI antibacterial prophylaxis have been proposed for these cases. Large prospective, controlled trials are needed to ascertain the role of oral SSI prophylaxis for these surgical sites and procedures especially in patients with diabetes mellitus who are intrinsically at greater risk of SSI. Topical antibacterial ointment and sterile paraffin appear to make no difference to healing or the incidence of SSIs in clean wounds. Although further research is needed, preliminary studies have shown that intraincisional antibacterials, which may be associated with fewer adverse effects and a lower risk of multidrug-resistant bacteria, could potentially be helpful for SSI prophylaxis. Trials using honey- and silver-impregnated dressings have found no advantage in the healing of chronic wounds. However, several case studies, which need corroboration in larger studies, suggest that these dressings may be helpful in preventing and treating SSIs. Bacterial endocarditis and joint prosthesis infection prophylaxis are not routinely recommended in cutaneous surgery. The updated 2007 American Heart Association guidelines now advocate bacterial endocarditis prophylaxis for high-risk cardiac patients having surgery involving the oral mucosa or infected skin. The latest American Dental Association/American Academy of Orthopaedic Surgery guidelines recommend considering antibacterial prophylaxis for oral procedures where bleeding is anticipated and for surgery involving acute orofacial skin infections if the patient has had a total joint replacement within 2 years or is in a high-risk group and has had a joint replacement at any time.

A simple prophylaxis regimen for MRSA: its impact on the incidence of infection in patients undergoing liver resection

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) infection has increased at an alarming rate in the recent past and has major cost implications. The aim of this study is to assess the impact of a policy of pre-operative MRSA prophylaxis on the incidence of MRSA infection in patients undergoing liver resection.

PATIENTS AND METHODS

A total of 585 patients underwent hepatectomy in a tertiary referral centre between January 2000 and September 2005. In September 2003, a policy of MRSA prophylaxis (nasal mupirocin and triclosan wash for 5 days) was introduced within this unit. Demographic, pathological and outcome data were compared between the pre- and post-MRSA prophylaxis cohorts.

RESULTS

The prevalence of MRSA infection prior to initiating the prophylaxis protocol was 29 patients (8.3%) and this fell to 9 patients (3.8%; P = 0.029). Furthermore, patients who had MRSA-related infection had a higher incidence of additional complications compared to the rest of the cohort (P = 0.001). Total cost savings incurred as a result of this protocol over the past 2 years has been approximated at 28,893 pounds.

CONCLUSIONS

Introduction of a simple MRSA prophylaxis policy has had a significant reduction on the incidence MRSA-related infection within our patient population, leading to reduced morbidity and cost saving to the UK National Health Service.

Staphylococcal surgical site infections

Staphylococcus aureus is the leading cause of surgical site infections (SSI) in the United States. In particular, SSI caused by methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a devastating complication, leading to increased mortality rates, increased length of hospitalization, and increased costs. Proven strategies for prevention of SSI caused by S aureus include addressing modifiable risk factors and correct choice and timing of antimicrobial prophylaxis. Other strategies, including decolonization and the use of vancomycin, remain controversial.

The efficacy of preoperative screening and the treatment of methicillin-resistant Staphylococcus aureus in an otolaryngology surgical practice

OBJECTIVE

To examine the efficacy of preoperative Staphylococcus aureus screening on postoperative methicillin-resistant S aureus (MRSA) infection rates in otolaryngology.

STUDY DESIGN

Chart review.

SUBJECTS AND METHODS

Postoperative MRSA infection rates in unscreened patients during a 1-year period were compared with infection rates in patients after preoperative S aureus screening was initiated. Colonized patients were treated with mupirocin and chlorhexidine preoperatively.

RESULTS

Records of 420 patients were reviewed. In the 241 patients without screening, nine patients had S aureus infections, and there were two (0.8%) postoperative MRSA surgical-site infections. Of 179 patients after screening was initiated, 24 patients (13.4%) were colonized with S aureus and underwent preoperative treatment. There were no MRSA infections in the postoperative period.

CONCLUSION

Early results show the potential benefit of preoperative S aureus screening in MRSA infection rate reduction. Although larger studies are needed, screening and treatment of MRSA colonized patients preoperatively may reduce infectious complications in otolaryngology.

Clinical effectiveness of ototopical application of mupirocin ointment in methicillin-resistant Staphylococcus aureus otorrhea

OBJECTIVE

Methicillin-resistant Staphylococcus aureus (MRSA) otorrhea has become an increasing problem with regard to infection through the tympanic membrane perforation and postsurgical infection. In particular, dry ear, at the preoperative stage, is considered to be a crucial factor in surgery. We evaluated how to control MRSA otorrhea before and after ear surgery.

PATIENTS AND METHODS

Twenty-six patients having MRSA otorrhea were enrolled in the present study and randomly divided into 2 groups, namely, mupirocin ointment therapy for 16 patients and ofloxacin ear drops for 10 patients. Approximately 0.6 mg of mupirocin ointment was administered locally to the tympanic membrane and the promontory around and through the perforation with its adjacent external ear canal 1 to 4 times for 2 or 3 weeks at the clinic. On the other hand, ofloxacin ear drops were administered daily by the patients for 2 or 3 weeks at home.

RESULTS

Complete elimination of MRSA from the ear was obtained in all patients of the mupirocin group. This showed a significant improvement (p < 0.001) as compared with the ofloxacin group (improvement + cure rate, 40%). Local application of mupirocin did not aggravate hearing acuity of any patients who were evaluated by pure-tone audiometry before and after treatment.

CONCLUSION

The present findings first indicate that minimally essential application of mupirocin ointment is an extremely useful ototopical agent against MRSA otorrhea without ototoxicity.

A preoperative decolonization protocol for staphylococcus aureus prevents orthopaedic infections

Staphylococcus aureus (S. aureus) is an independent risk factor for orthopaedic surgical site infection (SSI). To determine whether a preoperative decolonization protocol reduces S. aureus SSIs, we conducted a prospective observational study of patients undergoing elective total joint arthroplasty (TJA) at our institution, with two control groups. The concurrent control group comprised patients of surgeons who did not participate in the intervention study. The preintervention control group comprised patients of participating surgeons who had undergone elective TJA during the year before the study. Patients in the intervention group were screened preoperatively for S. aureus by nasal swab cultures. S. aureus carriers were decolonized with mupirocin ointment to the nares twice daily and chlorhexidine bath once daily for 5 days before surgery. All 164 of 636 participants (26%) who tested positive completed the decolonization protocol without adverse events and had no postoperative S. aureus SSIs at 1-year followup. In contrast, 1330 concurrent control patients had 12 S. aureus infections. If these infections had occurred in the 26% of patients expected to be nasal carriers of S. aureus at a given time, the infection rate would have been 3.5% (12 of 345) in the control group. In addition, the overall infection rate of the participating surgeons, including nonstaphylococcal infections, decreased from 2.6% during the preintervention period to 1.5% during the intervention period, translating to an adjusted economic gain of $231,741 for the hospital. The data suggest a preoperative decolonization protocol reduces S. aureus SSIs in patients undergoing TJA.

LEVEL OF EVIDENCE

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

Prevalence of methicillin-resistant Staphylococcus aureus among orthopedic patients at a large academic hospital

Community-based methicillin-resistant Staphylococcus aureus (MRSA) contributes to postoperative surgical site infections, and it is therefore important to eliminate nasal carriage of MRSA before surgery. A total of 678 nasal swabs were performed on elective orthopedic patients undergoing surgery with the usage of metal implants. Thirty-eight specimens (5.6%) were positive for MRSA and 146 (21.5%) were positive for methicillin-sensitive S aureus (MSSA). A slow increase in the number of MSSA was noted between 2006 and 2007. Positive cases of MRSA nasal carriage were treated with nasal mupirocin ointment and chlorhexidine baths or showers for 5 days prior to surgery.

Budget impact analysis of rapid screening for Staphylococcus aureus colonization among patients undergoing elective surgery in US hospitals

OBJECTIVE

To evaluate the economic impact of performing rapid testing for Staphylococcus aureus colonization before admission for all inpatients who are scheduled to undergo elective surgery and providing subsequent decolonization therapy for those patients found to be colonized with S. aureus.

METHODS

A budget impact model that used probabilistic sensitivity analysis to account for the uncertainties in the input variables was developed. Primary input variables included the marginal effect of S. aureus infection on patient outcomes among patients who underwent elective surgery, patient demographic characteristics, the prevalence of nasal carriage of S. aureus, the sensitivity and specificity of the rapid diagnostic test for S. aureus colonization, the efficacy of decolonization therapy for nasal carriage of S. aureus, and cost data. Data sources for the input variables included the 2003 Nationwide Inpatient Sample data and the published literature.

RESULTS

In 2003, there were an estimated 7,181,484 patients admitted to US hospitals for elective surgery. Our analysis indicated preadmission testing and subsequent decolonization therapy for patients colonized with S. aureus would have produced a mean annual cost savings to US hospitals of $231,538,400 (95% confidence interval [CI], -$300 million to $1.3 billion). The mean annual number of hospital-days that could have been eliminated was estimated at 364,919 days (95% CI, 67,893-926,983 days), and a mean of 935 in-hospital deaths (95% CI, 88-3,691) could have been avoided per year. Sensitivity analysis indicated a 64.5% probability that there would be cost savings to US hospitals as a result of preadmission testing and subsequent decolonization therapy.

CONCLUSION

The addition of preadmission testing and decolonization therapy to standard care would result in significant cost savings, even after accounting for variations in the model input values.

Bacterial interference for the prevention and treatment of infections

Bacterial interference refers to the antagonism between bacterial species during the process of surface colonisation and acquisition of nutrients. The clinical evidence on the potential applications of microorganisms for the prevention and/or treatment of infections in the upper respiratory, urogenital and gastrointestinal tracts was reviewed through the PubMed and Scopus databases. Data regarding factors that may affect the human microflora, thus contributing to tissue colonisation from potential pathogens, were also retrieved. The clinical evidence for application of the interfering ability of non-virulent bacteria to prevent or treat infections has been rather limited, although promising for certain purposes. A number of relevant preliminary trials suggest that in the upper respiratory tract the rate of recurrence of otitis media or streptococcal pharyngotonsillitis appears to decrease using selected bacteria with inhibitory ability against common pathogens of upper respiratory tract in combination with appropriate antibiotic treatment. Regarding the urogenital tract, specific non-pathogenic strains of Escherichia coli and probiotic organisms were successfully applied to decrease the recurrence of local infections. The interfering ability of specific probiotic organisms (strains of Lactobacilli and Bifidobacteria) within the gastrointestinal tract against common pathogens was also demonstrated. In conclusion, randomised controlled trials are warranted to investigate the effectiveness and safety of potential applications of the principle of bacterial interference in the prevention and treatment of infections of various sites. Such trials should initially employ selected strains of probiotics for which there are preliminary data regarding their effectiveness and lack of common or serious toxicity.

Impact of prophylactic mupirocin for radical esophagectomy

The preoperative intranasal application of mupirocin significantly decreases the rate of nosocomial S. aureus infections among patients who are S. aureus carriers. However, it remains unclear whether the routine preoperative use of mupirocin would reduce postoperative S. aureus infections, especially methicillin-resistant Staphylococcus aureus (MRSA) infections, and who would benefit from the prophylactic use of mupirocin. Ninety-six consecutive patients who had undergone elective radical esophagectomy with right thoracotomy and laparotomy were evaluated. Fifty-one patients were given 2% mupirocin calcium ointment 3 times daily over 3 consecutive days before surgery. Uni- and multivariate analyses were performed to identify factors affecting the following three issues: postoperative MRSA infection, postoperative pneumonia, and the length of postoperative hospital stay. In univariate analyses, the preoperative application of mupirocin significantly reduced MRSA infection, postoperative pneumonia, and length of postoperative hospital stay. Multivariate analyses indicated significant associations between mupirocin administration and reductions in both MRSA infection and postoperative pneumonia, but not in length of postoperative hospital stay. Radical esophagectomy with right thoracotomy and laparotomy for esophageal carcinoma warranted the preoperative prophylactic administration of mupirocin in order to reduce postoperative infectious complications from MRSA. Its routine use for such a high-risk procedure is entirely reasonable.

Perioperative intranasal mupirocin for the prevention of surgical-site infections: systematic review of the literature and meta-analysis

OBJECTIVE

To review the evidence evaluating perioperative intranasal mupirocin for the prevention of surgical-site infections according to type of surgical procedure.

DESIGN

Systematic review and meta-analysis of published clinical trials.

SETTING

Studies included were either randomized clinical trial or prospective trials at a single institution that measured outcomes both before and after an institution-wide intervention (before-after trial). In all studies, intervention and control groups differed only by the use of perioperative intranasal mupirocin in the intervention group.

PATIENTS

Patients undergoing general or nongeneral surgery (eg, cardiothoracic surgery, orthopedic surgery, and neurosurgery).

MAIN OUTCOME MEASURE

Risk of surgical-site infection following perioperative intranasal mupirocin versus usual care.

RESULTS

Three randomized and four before-after trials met the inclusion criteria. No reduction in surgical-site infection rate was seen in randomized general surgery trials (summary estimates: 8.4% in the mupirocin group and 8.1% in the control group; relative risk [RR], 1.04; 95% confidence interval [CI95], 0.81 to 1.33). In nongeneral surgery, the use of mupirocin was associated with a reduction in surgical-site infection in randomized trials (summary estimates: 6.0% in the mupirocin group and 7.6% in the control group; RR, 0.80; CI95, 0.58 to 1.10) and in before-after trials (summary estimates: 1.7% in the mupirocin group and 4.1% in the control group; RR, 0.40; CI95, 0.29 to 0.56).

CONCLUSIONS

Perioperative intranasal mupirocin appears to decrease the incidence of surgical-site infection when used as prophylaxis in nongeneral surgery. Given its low risk and low cost, use of perioperative intranasal mupirocin should be considered in these settings.

Multicenter experience: prevention and management of left ventricular assist device infections

Implantable left ventricular assist devices (LVADs) have demonstrated clinical success in both the bridge-to-transplantation and destination-therapy patient populations; however, infection remains one of the most common causes of mortality during mechanical circulatory support. Thus, serious LVAD infections may negate the benefits of LVAD implantation, resulting in decreased quality of life, increased morbidity and mortality, and increased costs associated with implantation. Prevention of device-related infection is crucial to the cost-effective use of mechanical circulatory support devices. Therefore, adherence to evidence-based infection control and prevention guidelines, meticulous surgical technique and optimal postoperative surgical site care form the foundation for LVAD associated infection prevention.

Current strategies for prevention of surgical site infections

Surgical site infections (SSIs) are a common complication that follows all types of operative procedures. These infections are usually caused by the exogenous and endogenous microorganisms that enter the operative wound during the course of surgery. The general and procedure-specific risk factors for the development of SSI have been identified and are discussed in this article. Factors that influence the SSI rate and the current strategies for prevention of SSIs are also presented. Emphasis is placed on the efficacious use of antibiotic prophylaxis in surgery. A discussion of the principles of antibiotic prophylaxis, including choice of agents, route of administration, and timing, is offered. It appears that the use of less invasive laparoscopic surgical approaches, as practiced widely today, will be associated with an overall decreased incidence of SSI.