Infection In Orthopedic Surgery Research Articles

Monitoring medical procedures by exponential smoothing

A new exponentially weighted moving average (EWMA) control chart well suited for 'online' routine surveillance of medical procedures is introduced. The chart is based on inter-event counts for failures recorded when the failures occur. The method can be used for many types of hospital procedures and activities, such as problems or errors in surgery, hospital-acquired infections, erroneous handling or prescription of medicine, deviations from scheduled treatments causing inconveniences for patients. The construction, the use and the effectiveness of the control chart are demonstrated by two well-known examples about wound infection in orthopaedic surgery and neonatal arterial switch surgery. The method is easy to implement and apply, it illustrates, estimates and tests the current failure rate. Comparisons with two examples from the literature indicate that its ability to quickly detect an increased failure rate is comparable to that of other well-established methods.

Effect of Antibiotic Treatment on Bacterial Attachment to a DePuy EnduronTM Orthopedic Implant

Background: The increasing incidence of bacterial infections in orthopedic surgery might be related to the increasing application of artificial devices. In most cases, bacteria multiply on the surface of implants in biofilms. Poor penetration of antibiotics, frequent necessity of prosthesis removal, chronic processes and financial costs emphasize the significance of preventive measures. Method: Adhesion of bacterial strains (two Staphylococcus aureus, two coagulase-negative staphylococci and two Pseudomonas aeruginosa strains isolated from orthopedic patients’ wounds) to the surface of a polyethylene cupwas investigated using an ultrasonic method. Results were compared to the adhesive ability of three Hungarian standard strains. The effect of antibiotic treatment (cefuroxime, cefotaxime, amoxicillin with clavulanic acid and amikacin) has been examined. Results: The staphylococcal strains showed significantly higher adhesive ability than Pseudomonas strains. Antibiotic treatment significantly reduced the attachment of bacteria. The higher the concentration of the antibiotics, the higher was the decrease in bacterial adhesion. Conclusions: Antibiotic prophylaxis was proven to be effective against bacterial adhesion, and, if applied at the proper time at the highest tolerable dose, it might prevent the formation of biofilms.

A new model of implant-related osteomyelitis in rats.

Infection related to osteosynthesis often has dramatic consequences for the patient. Prolonged hospitalization with systemic antibiotic therapy, several revision procedures, possible amputation, and even death may occur. To investigate the pathology of infection in orthopedic surgery, a new rat model of implant related osteomyelitis was developed. Three different concentrations (10(6), 10(3), and 10(2) colony-forming units (CFU)/10 microl) of Staphylococcus aureus were inoculated into the tibial medullary cavity with simultaneous insertion of a titanium Kirschner wire. Controls received phosphate-buffered saline (PBS). Each group consisted of 10 animals. Animals were followed for 4 weeks until sacrifice. X-rays of the tibiae were taken weekly, blood counts were analyzed, and body temperature and weight were determined. After sacrifice, infection was evaluated by histological and microbiological investigations. All animals inoculated with Staph. aureus in either concentration developed microbiological, histological, and radiological signs of osteomyelitis in correlation to the amount of inoculated bacteria. X-rays clearly revealed osseous destruction after 14 days with progression of osteomyelitis during the following weeks. CFU/g bone and bone weight after sacrifice showed dependence on the amount of inoculated CFU. The histological results confirmed the radiological findings. No significant changes in blood counts, body weight, and body temperature between the groups could be observed. The results demonstrate that it is possible to develop a model of implant-related osteomyelitis in rats with dependence on the amount of inoculated bacteria. No other promoters of infection besides intramedullary insertion of titanium Kirschner wires were used in this model.

Effect of Antibiotics on Cell Surface Hydrophobicity of Bacteria Causing Orthopedic Wound Infections

Background: Despite antibiotic prophylaxis and treatment, the incidence of wound infections in orthopedic surgery is significant. Postoperative wound infection is a multifactorial process, which can be modified by several bacterial factors. Cell surface hydrophobicity of bacteria is a very important physicochemical feature, which has a great influence on the ability of bacteria to adhere to the surface of host cells or medical implants. Methods: In this study, the hydrophobic properties of thirteen bacterial strains (coagulase-negative staphylococci, Staphylococcus aureus and Pseudomonas aeruginosa) isolated from patients with postoperative deep wound infections following orthopedic procedures were determined by the salt aggregation test. Results were compared to the hydrophobicity of three Hungarian standard bacterial strains. The modifying effect of four antibiotics (cefuroxime, cefotaxime, amoxicillin combined with clavulanic acid and amikacin) – applied most often in our Department for prophylaxis and treatment of patients – were analyzed. Results: The cell surface hydrophobicity of certain strains showed considerable changes after antibiotic treatment. These alterations indicated the decrease in hydrophobicity. Supra-inhibitory concentrations (2× minimum inhibitory concentrations, MIC) of the antibiotics were able to induce more frequent alterations in hydrophobicity than sub-inhibitory (0.5× MIC) levels. Conclusions: Alterations in cell surface hydrophobicity caused by antibiotics can modify the adhesion process and thus the pathogenicity of bacterial strains. These changes should be taken into consideration in the management of proper antibiotic prophylaxis and in the treatment of orthopedic patients.

Antibiotics in the prevention of the surgical site infection in orthopedic surgery

Surgical site infection is an actual problem of orthopaedic surgery. Despite considerable efforts that have been done during last several decades (e.g. improvements in surgical techniques, preoperative preparation of the surgical site, infection-control practice, use of preventive antibiotics) surgical site infection still affects about 0.5-2% of patients after closed fracture surgery or insertion of prosthetic devices. They are associated with substantial morbidity and mortality. The adherence to the principles of rationale preventive antibiotic therapy has an important role in the prevention of the surgical infection. In addition, it is well known that inappropriate use of antibiotic promote development of resistance, superinfections and increase the cost of the treatment. This paper focuses on the basic principles of rational use of antibiotics, i.e. appropriate selection of drug, dose, and duration of treatment in the prevention of surgical site infections in orthopaedic surgery.

Severe necrotising soft tissue infections in orthopaedic surgery.

To review all cases of necrotising infection managed in the Department of Orthopaedic Surgery of Dunedin Hospital in New Zealand between 1989 and 1998. Hospital records were analysed for predisposing factors, clinical features, diagnostic results, treatment strategies, and outcomes. 13 cases (9 males and 4 females) of necrotising infection were identified. The mean age was 48 years (range, 8-76 years). Presenting symptoms included painful swelling, erythema, and necrosis. Most patients had predisposing factors and had received nonsteroidal anti-inflammatory drugs before presentation. 12 patients underwent surgical debridement including a total of 4 amputations. Septic shock developed in 9 patients who required dialysis for renal failure. Four patients died. The most common organisms identified were group A beta-haemolytic streptococci. Severe necrotising infections require a high index of suspicion and rapid medical and surgical intervention to reduce the mortality and morbidity.

The infection in orthopaedic surgery

The infection in orthopaedic surgery

An audit of microbiology laboratory utilization: the diagnosis of infection in orthopedic surgery

OBJECTIVE: To analyse the quality of ordering, collection and transport of specimens for microbiological analysis by a department of orthopedic surgery. METHODS: The analysis consisted of a prospective formal evaluation performed by two consultant microbiologists. RESULTS: One hundred and seventeen consecutive requests were audited. These requests belonged to 55 clinical episodes, 39 of which were of (presumed) infection and 16 of surveillance. The main sites sampled were: joint 28 (51%), and extra-articular bone or tissue 6 (11%). Of 98 surgical specimens, 20 (20%) yielded a relevant microorganism. The requests were classified as definitely appropriate in 67% and 85% of episodes, by the two consultants respectively. No request was considered unjustified. Collection, handling and transport were categorized as definitely appropriate in 56% and 73% of requests. Analysis of compliance with an existing protocol for prosthetic joint revision revealed similar errors. CONCLUSION: Audits of this type can give invaluable information about the area of uncertainty between the clinician and the laboratory and can identify appropriate measures for corrective action.

Infections en chirurgie orthopédique - facteurs de risque et prophylaxie

The authors describe prophylaxis of infections in orthopaedic surgery caused by various factors:- accurate selection of patients (evaluation of diabetes, hemopathies, nephropathies, iatrogenic and acquired immune deficits); - operating room and surgical technique risk factors (endogenous and exogenous contamination, skin preparation, surgeon's skill in performing non aggressive surgery, duration of surgery); - antibiotic prophylaxis with specific pharmacological characteristics (wide spectrum drugs with low toxicity) and chronological criteria (time and duration of prophylaxis). The main preventive measures against infection are reported. The high percentage of infections (11 %) in prosthetic surgery has been due to risk factors existing before surgery (diabetes, hemopathy, immune deficiency).

The Clinical Significance of CRP for the Postoperative Infection in Orthopedic Surgery

The Clinical Significance of CRP for the Postoperative Infection in Orthopedic Surgery

Nutrition: Its Relationship to Orthopedic Infections

The malnutrition of orthopedic surgical patients plays an important role in the development of complications, including infection. A high index of suspicion that malnutrition exists or will soon exist in patients who are subjected to significant stress, trauma, or surgery will lead the clinician to take measures to avoid further protein calorie deficits and replenish the patient's nutritional needs. There are many pathways in which malnutrition causes a propensity for infection, and these have been discussed. Meeting the patient's nutritional needs should avoid some of the complications of infections in orthopedic surgery.

Topical Antibiotic Irrigation in the Prophylaxis of Operative Wound Infections in Orthopedic Surgery

1. Although the orthopedic literature on the clinical use of topical antibiotics is sparse, the effectiveness of topical antibiotics has been shown well enough in vitro and in the surgical literature to justify strong consideration of their use in orthopedic procedures. 2. Saline irrigation should not be relied upon to reduce bacterial contamination completely, although it does remove debris, foreign material, and clot, which often contain bacteria, from the surgical wound. 3. Topical antibiotic agents used for irrigation should have a broad spectrum of antimicrobial activity. Triple antibiotic solution (neomycin, polymyxin, and bacitracin) provides the most complete coverage against the organisms most likely to cause infections in both clean and contaminated orthopedic surgical cases. These agents should be allowed to remain in the wound for at least 1 minute before their removal. 4. Further studies of topical antibiotic irrigation in orthopedic surgery are needed to demonstrate the most effective antibiotic(s) and technique of administration. 5. There is evidence to suggest that the more often an irrigant is used, the more effective it is in preventing infection. 6. The use of bacitracin as an irrigant should probably be avoided in patients previously exposed to that agent. 7. Antibiotic-containing solutions should be utilized with pulsatile lavage systems. Saline alone may drive previously administered antibiotics from bone, leaving insufficient local antibiotic levels.

99Tcm hexamethylpropyleneamineoxime-labelled leucocyte scanning for detection of infection in orthopaedic surgery--first results.

99Tcm hexamethylpropyleneamineoxime-labelled leucocyte scanning for detection of infection in orthopaedic surgery--first results.

Occurrence of methicillin-resistant Staphylococcus aureus in a department of orthopedic surgery 1970 to 1986.

The incidence of methicillin-resistant (and multiply-resistant) strains of Staphylococcus aureus in the Department of Orthopedic Surgery at Odense University Hospital fell from 15% of all strains in 1970 to less than 0.5% in 1986. This decrease occurred more slowly in the orthopedic department than in the rest of the hospital. A retrospective survey of 30 episodes of infection due to methicillin-resistant Staphylococcus aureus from 1979 to 1986 indicates that this slower decrease may be due to the relatively frequent occurrence of chronic infections in orthopedic surgery.

Pyogenic infections in orthopaedic surgery: Combined antibiotic and closed wound treatment

This is a preliminary report of experiences in the treatment of serious pyogenic infections of the motor-skeletal system in adults. Established surgical principles of treatment of infected wounds was observed. Open wound treatment was abandoned in favor of the closed technic with intermittent suction and combined antibiotic therapy. Antibiotic combinations were selected for simultaneous systemic and local administration in accordance with in vitro determinations of bactericidal activity. In addition to usual clinical criteria of success of treatment, periodic wound culture studies and assays of sera and wound exudates for antimicrobial activity were thought to provide dependable guidance. The results of treatment of acute postoperative infections in this small series was encouraging and have stimulated further study. Six acute infections following prosthetic arthroplasty were controlled and subsequently removal of metallic foreign bodies was not necessary because of recurrent infection. Analysis of two failures of treatment of infection after prosthetic arthroplasty suggested factors that in retrospect might have been significant causes. The most discouraging results were encountered in chronic or recurrent infections of bone where necrotic tissue, infected granulation tissue or extensive scarring of soft tissue were present. Inadequate operative removal of infected or necrotic tissue could not be compensated by adjunctive chemotherapy. Certain advantages and disadvantages of closed wound treatment and combined antibiotic therapy are discussed.