Salvage of infected expander prostheses in breast reconstruction

Periprosthetic infection is a devastating complication following breast reconstruction with prostheses. Traditional surgical principles dictate removal of the prosthesis to control infection. Although successful salvage of prostheses in the presence of periprosthetic infections has been reported in the plastic and other surgical literature, salvage procedures remain seldom practiced. Reports in the plastic surgery literature have been limited to implant salvage following cosmetic breast augmentation and subcutaneous mastectomy with implants. Salvage of saline-filled expander prostheses used in breast reconstruction following mastectomy for cancer has not been previously reported. The authors review their experience with implant salvage in patients with periprosthetic infections following breast reconstruction for a 6-year period. Fourteen patients (13 with saline-filled expander prostheses and one with silicone prosthesis) underwent implant salvage. Salvage of the breast reconstruction was successful in nine patients. Staphylococcus aureus infection was associated with poorer salvage rate (p = 0.023). Previous radiotherapy to the chest wall did not affect the salvage outcome (p = 0.50). In selected patients, immediate salvage of a breast reconstruction in the presence of prosthesis-related infection remains an alternative to implant removal followed by delayed reconstruction.     

The pharmacokinetics of cefazolin in patients undergoing elective & semi-elective abdominal aortic aneurysm open repair surgery

Background

Surgical site infections are common, so effective antibiotic concentrations at the sites of infection are required. Surgery can lead to physiological changes influencing the pharmacokinetics of antibiotics. The aim of the study is to evaluate contemporary peri-operative prophylactic dosing of cefazolin by determining plasma and subcutaneous interstitial fluid concentrations in patients undergoing elective of semi-elective abdominal aortic aneurysm (AAA) open repair surgery.

Methods/Design

This is an observational pharmacokinetic study of patients undergoing AAA open repair surgery at the Royal Brisbane and Women's Hospital. All patients will be administered 2-g cefazolin by intravenous injection within 30-minutes of the procedure. Participants will have samples from blood and urine, collected at different intervals. Patients will also have a microdialysis catheter inserted into subcutaneous tissue to measure interstitial fluid penetration by cefazolin. Participants will be administered indocyanine green and sodium bromide as well as have cardiac output monitoring performed and tetrapolar bioimpedance to determine physiological changes occurring during surgery. Analysis of samples will be performed using validated liquid chromatography tandem mass-spectrometry. Pharmacokinetic analysis will be performed using non-linear mixed effects modeling to determine individual and population pharmacokinetic parameters and the effect of peri-operative physiological changes on cefazolin disposition.

Discussion

The study will describe cefazolin levels in plasma and the interstitial fluid of tissues during AAA open repair surgery. The effect of physiological changes to the patient mediated by surgery will also be determined. The results of this study will guide clinicians and pharmacists to effectively dose cefazolin in order to maximize the concentration of antibiotics in the tissues which are the most common site of surgical site infections.     

Craniofacial infection in 10 years of transcranial surgery

Infection following transcranial surgery may be devastating. A review of 170 transcranial operations is presented with a focus on postoperative infection and its relationship to patient age, preoperative microbiology, pattern of operation, length of operation, and the use of antibiotic prophylaxis. The overall postoperative infection rate was 6.5 percent, but the infection rate in adults (23.5 percent) was much higher than in children (2.2 percent). Higher infection rates were found in adults with craniofacial dysostoses undergoing lengthy frontofacial advancements which required tracheostomy airway management. The residual frontal extradural dead space following advancement in adults is a sanctuary to infecting organisms from the respiratory tract--especially Pseudomonas transferred from the tracheostomy site into the upper airway and intracranial dead space by ventilation forces. Operating times for patients who became infected were 2 1/2 hours longer than average operating times for transcranial operations. Preoperative microbiology of the craniofacial region was not a good predictor of subsequent infection. Recommendations include operative intervention at an early age, short preoperative hospital stay, antibiotic prophylaxis to include gram-negative cover, surgical measures to either fill or isolate the dead space, and strict tracheostomy care--preferably with the patient being barrier-nursed.     

Systematic Review of the Literature and Evidence-Based Recommendations for Antibiotic Prophylaxis in Trauma: Results from an Italian Consensus of Experts

Background

Antibiotic prophylaxis is frequently administered in severe trauma. However, the risk of selecting resistant bacteria, a major issue especially in critical care environments, has not been sufficiently investigated. The aim of the present study was to provide guidelines for antibiotic prophylaxis for four different trauma-related clinical conditions, taking into account the risks of antibiotic-resistant bacteria selection, thus innovating previous guidelines in the field.

Methods

The MEDLINE database was searched for studies comparing antibiotic prophylaxis to controls (placebo or no antibiotic administration) in four clinical traumatic conditions that were selected on the basis of the traumatic event frequency and/or infection severity. The selected studies focused on the prevention of early ventilator associated pneumonia (VAP) in comatose patients with traumatic brain injury, of meningitis in severe basilar skull fractures, of wound infections in long-bone open fractures. Since no placebo-controlled study was available for deep surgical site-infections prevention in abdominal trauma with enteric contamination, we compared 24-hour and 5-day antibiotic prophylaxis policies. A separate specific research focused on the question of antibiotic-resistant bacteria selection caused by antibiotic prophylaxis, an issue not adequately investigated by the selected studies. Randomised trials, reviews, meta-analyses, observational studies were included. Data extraction was carried out by one author according to a predefined protocol, using an electronic form. The strength of evidence was stratified and recommendations were given according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria.

Results

Uncertain evidence deserving further studies was found for two-dose antibiotic prophylaxis for early VAP prevention in comatose patients. In the other cases the risk of resistant-bacteria selection caused by antibiotic administration for 48 hours or more, outweighed potential benefits.

Conclusions

When accounting for antibiotic-resistant bacteria selection we found no evidence in favour of antibiotic prophylaxis lasting two or more days in the studied clinical conditions.     

The role of the plastic surgeon in the management of surgical infection.

At our Medical Center, our reconstructive service has actively sought referrals of acute and chronic infections by declaring an interest in undertaking the integrated management and reconstruction of these cases. The practices of the two senior surgeons were reviewed for three academic years (1992 to 1995). Cases of surgical infection were analyzed as to site, ablative procedures, and reconstructive procedures. In total, 139 patients with 147 infections were identified. Sites of infection included head and neck (9.5 percent), trunk and pelvis (39.5 percent), upper extremity (22 percent), and lower extremity (29 percent). One-hundred thirty-one ablative procedures were done on this group, as were 126 reconstructive procedures, including 17 fasciocutaneous flaps, 26 pedicled muscle flaps, and 28 microsurgical flaps. With a mean follow-up of 14 months, 92 percent of these patients had resolution of infection. The 8 percent failure group included recurrences, amputation, and death. This series demonstrates that a plastic surgery service can attract a diverse population of surgical infections and manage them successfully with ablation and a wide variety of reconstructive procedures. The coordination of ablation and reconstruction may be optimally performed by the plastic surgeon.     

Utilisation des céphalosporines comme antibioprophylaxie lors de césariennes.

Cefoxitin, a second-generation cephalosporin, was compared with cefazolin, a first-generation cephalosporin, and a placebo in a prospective, double-blind study of antibiotic prophylaxis in women undergoing nonelective cesarean section. In the groups that received cefazolin or the placebo there eas no statistically significant change in colonization of the cervix by aerobic bacteria by the fourth day after the operation, but there was a statistically significant increase in colonization by anaerobes. Cefoxitin had the opposite effect. Of the 14 postoperative infections in 11 patients, significantly more were in patients who had received the placebo; the numbers were too small to show a difference in effectiveness between the two antibiotics. Of the microorganisms implicated as the infectious agents, group B Streptococcus was the most frequent aerobe, and Peptostreptococcus and Bacteroides bivius were the most frequent anaerobes. Among the 15 patients for whom at least one perioperative specimen yielded positive culture results, a postoperative infection developed in 5 of the 6 who received the placebo, 2 of the 4 who received cefazolin and 1 of the 5 who received cefoxitin.     

Surgical Site Infections after Deep Brain Stimulation Surgery: Frequency,Characteristics and Management in a 10-Year Period

Background/Aims

Deep brain stimulation (DBS) implant infection is a feared complication, as it is difficult to manage and leads to increased patient morbidity. We wanted to assess the frequency and possible risk factors of DBS related infections at our centre. In the purpose of evaluating treatment options, we also analyzed treatment, and the clinical and microbiological characteristics of the infections.

Methods

Electronic medical records of all patients undergoing DBS surgery at our centre, from 2001 through 2010, were retrospectively reviewed.

Results

Of the 588 procedures performed 33 (5.6%) led to an infection. Some patients underwent several procedures, thus 32 out of totally 368 patients (8.7%), and 19 out of 285 patients (6.7%) who received primary lead implantation, developed an infection. Most infections (52%) developed within the first month and 79% within three months. In the majority of the infections (79%) hardware removal was performed. Staphylococcus aureus infections were the most frequent (36%), and more likely to have earlier onset, pus formation, a more aggressive development and lead to hardware removal. No risk factors were identified.

Conclusions

Our results indicate that infections with more severe symptoms and growth of staphylococcus aureus should be treated with local hardware removal and antibiotic therapy. In other infections, an initial trial of antibiotic treatment could be considered. New knowledge about the microbiology of DBS related infections may lead to more effective antimicrobial treatment.     

Mycobacterium marinum infections of the upper extremity

A significant number of patients infected with Mycobacterium marinum have been treated at the Curtis National Hand Center in Baltimore, Maryland. The purpose of this study was to review the authors' experience with M. marinum infections of the upper extremity. Twenty-nine patients were identified and their charts were reviewed for all factors related to diagnosis and treatment. The most common presenting symptoms were swelling (n = 25) and pain (n = 14). Only 69 percent of patients could correlate their injury with aquatic activities. The mean time from injury to diagnosis was 5.2 months. Acid-fast bacilli stains were positive in only 22 percent of specimens. The mean number of procedures was 1.75, with the majority being tenosynovectomy. The mean duration of antibiotic therapy was 6 months. Clinical history, pathological evaluation, and a high clinical suspicion can lead to early diagnosis and introduction of antibiotics. The authors' patients were successfully treated with 6 months of antibiotic therapy and early surgical intervention.     

Prophylactic antibiotics in plastic and reconstructive surgery.

There is no consensus in the literature on the use of prophylactic antibiotics to prevent postoperative infection. This study was performed to investigate whether the use of prophylactic antibiotics has an effect on postoperative infection rates. A total of 1400 patients were classified into four groups based on their diagnosis. During the induction of anesthesia, half of each group received 2 g of a sulbactam-ampicillin combination and the other half received a placebo (saline solution) intravenously. Wound infection rates were observed in the postoperative period. Age, sex, and operative site of the patients with the same diagnosis were comparable in each group. The white blood cell count and the body temperature reading of each patient were recorded postoperatively. Wounds were observed daily in the postoperative period and graded according to a predetermined scale. Bacteriologic specimens were obtained from patients who had wound infections. According to our clinical experience, antibiotic prophylaxis is not necessary in plastic surgery. At the end of our 6-year study, a significant difference could not be found between the antibiotic prophylaxis and placebo groups.     

Factors affecting outcome in free-tissue transfer in the elderly

Free-tissue transfers have become the preferred surgical technique to treat complex reconstructive defects. Because these procedures typically require longer operative times and recovery periods, the applicability of free-flap reconstruction in the elderly continues to require ongoing review. The authors performed a retrospective analysis of 100 patients aged 65 years and older who underwent free-tissue transfers to determine preoperative and intraoperative predictors of surgical complications, medical complications, and reconstructive failures. The parameters studied included patient demographics, past medical history, American Society of Anesthesiology (ASA) status, site and cause of the defect, the free tissue transferred, operative time, and postoperative complications, including free-flap success or failure. The mean age of the patients was 72 years. A total of 46 patients underwent free-tissue transfer after head and neck ablation, 27 underwent lower extremity reconstruction in the setting of peripheral vascular disease, 10 had lower extremity traumatic wounds, nine had breast reconstructions, four had infected wounds, two had chronic wounds, and two underwent transfer for lower extremity tumor ablation. Two patients had an ASA status of 1, 49 patients had a status of 2, 45 patients had a status of 3, and four had a status of 4. A total of 104 flaps were transferred in these 100 patients. There were 49 radial forearm flaps, 34 rectus abdominis flaps, seven latissimus dorsi flaps, seven fibular osteocutaneous flaps, three omental flaps, three jejunal flaps, and one lateral arm flap. Four patients had planned double free flaps for their reconstruction. Mean operative time was 7.8 hours (range, 3.5 to 16.5 hours). The overall flap success rate was 97 percent, and the overall reconstructive success rate was 92 percent. There were six additional reconstructive failures related to flap loss, all of which occurred more than 1 month after surgery. Patients with a higher ASA designation experienced more medical complications (p = 0.03) but not surgical complications. Increased operative time resulted in more surgical complications (p = 0.019). All eight cases of reconstructive failure occurred in patients undergoing limb salvage surgery in the setting of peripheral vascular disease. Free-tissue transfer in the elderly population demonstrates similar success rates to those of the general population. Age alone should not be considered a contraindication or an independent risk factor for free-tissue transfer. ASA status and length of operative time are significant predictors of postoperative medical and surgical morbidity. The higher rate of reconstructive failure in the elderly peripheral vascular disease population compares favorably with other treatment modalities for this disease process.     

Prophylactic use of cephazolin against wound sepsis after cholecystectomy.

A trial of antibiotic prophylaxis with cephazolin against postoperative wound sepsis was carried out on 201 patients undergoing routine cholecystectomy. Wound sepsis occurred in 11 out of 65 controls (16.9%), who were not given the drug; two out of 63 patients (3.2%) given a single dose preoperatively; and four out of 73 patients (5.5%) given the single preoperative dose plus a five-day course postoperatively. The difference between the controls and patients given the single preoperative dose was significant.     

Management of early human bites of the hand: a prospective randomized study

A prospective, randomized study was undertaken to determine if mechanical care of early human bites alone is sufficient therapy in the compliant patient or if prophylactic antibiotics (oral versus parenteral) are indicated. Beginning in June of 1985, patients presenting with human bites of the hand were entered into the study if (1) the bite was less than 24 hours old, (2) the patient was free of infection, (3) the bite did not penetrate the joint capsule, and (4) there was no injury to tendon. Forty-eight patients were ultimately segregated into one of three study groups after standardized ER mechanical wound care. Fifteen patients received an oral placebo, with 7 developing infection (46.7 percent). Sixteen patients received an oral antibiotic, and 17 patients received parenteral antibiotics. No infections were found in either of these latter groups. The results statistically substantiate that mechanical wound care alone is insufficient therapy. Oral antibiotics appear to be equal to intravenous antibiotics for prophylaxis. From a cost-benefit standpoint, vigorous cleaning, debridement, and coverage with a broad-spectrum oral antibiotic are adequate care for an uncomplicated bite in the compliant patient.     

Controlled Delivery of Vancomycin via Charged Hydrogels

Surgical site infection (SSI) remains a significant risk for any clean orthopedic surgical procedure. Complications resulting from an SSI often require a second surgery and lengthen patient recovery time. The efficacy of antimicrobial agents delivered to combat SSI is diminished by systemic toxicity, bacterial resistance, and patient compliance to dosing schedules. We submit that development of localized, controlled release formulations for antimicrobial compounds would improve the effectiveness of prophylactic surgical wound antibiotic treatment while decreasing systemic side effects. Our research group developed and characterized oligo(poly(ethylene glycol)fumarate) / sodium methacrylate (OPF/SMA) charged copolymers as biocompatible hydrogel matrices. Here, we report the engineering of this copolymer for use as an antibiotic delivery vehicle in surgical applications. We demonstrate that these hydrogels can be efficiently loaded with vancomycin (over 500 μg drug per mg hydrogel) and this loading mechanism is both time- and charge-dependent. Vancomycin release kinetics are shown to be dependent on copolymer negative charge. In the first 6 hours, we achieved as low as 33.7% release. In the first 24 hours, under 80% of total loaded drug was released. Further, vancomycin release from this system can be extended past four days. Finally, we show that the antimicrobial activity of released vancomycin is equivalent to stock vancomycin in inhibiting the growth of colonies of a clinically derived strain of methicillin-resistant Staphylococcus aureus. In summary, our work demonstrates that OPF/SMA hydrogels are appropriate candidates to deliver local antibiotic therapy for prophylaxis of surgical site infection.     

Characterisation of Staphylococcus aureus nasal and skin carriage among patients undergoing haemodialysis treatment

The aim of the study was to investigate the rate of Staphylococcus aureus nasal and skin carriage in patients undergoing haemodialysis. The cultured staphylococcal isolates were subsequently characterized by molecular methods. The study group comprised 43 haemodialysed patients from whom nasal and skin swabs from the vascular access sites were collected. The identification of staphylococcal isolates and antibiotic susceptibility testing were performed on the basis of conventional diagnostic procedures. The staphylococci were further characterized using Pulsed-Field Gel Electrophoresis (PFGE). S. aureus was cultured from 12 (27.9%) patients. Only one (8.3%) patient was colonized with the microorganism both in the anterior nares and the vascular access site representing a single strain, as evidenced by PFGE analysis. Antibiotic susceptibility testing identified one (7.6%) methicillin-resistant S. aureus (MRSA) strain. PFGE typing identified several S. aureus genotypes with the lack of one specific strain responsible for colonization. However, it should be noted that among two (A and D) PFGE patterns genetically indistinguishable and closely related isolates (two isolates for each pattern) were identified. The obtained results revealed a relatively low rate of S. aureus carriage accompanied by low methicillin resistance rate and a significant genetic diversity of cultured isolates with the lack of one predominant strain responsible for colonization.     

Optimizing breast pocket irrigation: an in vitro study and clinical implications

Subclinical infections have been implicated in the etiology of capsular contracture. Intraoperatively, breast pocket irrigation with povidone-iodine or other antibiotic solutions has been popularized; however, detrimental effects on wound healing for these agents have been reported and their efficacy against common organisms found around breast implants has not been studied. The purpose of this study was to compare the in vitro efficacy of serial dilutions of povidone-iodine and two double antibiotic solutions DAB-1 (gentamicin/polymyxin B) and DAB-2 (gentamicin/cefazolin), against organisms most commonly found around breast implants. In phase I trials, serial dilutions of povidone-iodine and DAB were combined 1:1 with cultures of five common organisms found around implants. In phase II, povidone-iodine was serially diluted in DAB-1 rather than saline. In phase III, povidone-iodine was serially diluted with DAB-2. Efficacy for all phases was determined by plating the mixture onto agar plates and incubating at 37 degrees C for 48 hours. Povidone-iodine was 100 percent effective at a dilution of 12.5% against Staphylococcus epidermidis and 25% against Staphylococcus aureus but relatively ineffective against Escherichia coli and Pseudomonas, DAB-1 was found to be ineffective against S. epidermidis but effective against S. aureus, Propionibacterium acnes, E. coli, and Pseudomonas. In phase II trials, a concentration of 12.5% povidone-iodine in DAB was effective at killing all experimental bacteria. In phase III trials, 10% povidone-iodine in DAB-2 was effective at killing all bacteria tested. In conclusion, to maximize bacterial control of common breast implant organisms and to minimize the detrimental effects on wound healing, 10% povidone-iodine in gentamycin/cefazolin may be used with excellent results and its use clinically may reduce the incidence of capsular contracture.     

Chemonucleolysis.

A double-blind trial of perioperative intravenous metronidazole treatment to prevent infections at the operative site and unexplained fever after abdominal hysterectomy was conducted in 106 patients. Metronidazole prophylaxis reduced the rate of recovery of anaerobes from vaginal swabs for several days and prolonged the high rate of vaginal carriage of enterococci and aerobic gram-negative bacilli following hysterectomy. Although the fever index, calculated from the duration of a temperature above 37.3 degrees C, was significantly lower in the metronidazole-treated group than in the placebo-treated group, the frequency of postoperative infections, the proportion of patients requiring antibiotic treatment and the average duration of hospital stay were similar in the two groups. These results do not support the reported value of perioperative metronidazole prophylaxis in patients undergoing abdominal hysterectomy.     

Survey of antibiotic prophylaxis in gastrointestinal surgery in Scotland.

The current use of prophylactic antibiotics in gastrointestinal surgery in Scotland was established by postal questionnaire. Twenty-one per cent of surgeons used prophylactic antibiotics during cholecystectomy, 49% during appendicectomy, and 95% for elective colorectal surgery. Two-thirds of those surgeons who did not provide routine antibiotic cover considered that the incidence of wound sepsis in their surgical practice was too low to merit special measures. Most surgeons using prophylaxis chose an appropriate antibiotic. The parenteral route for administration of antibiotic was used by 93% of surgeons during cholecystectomy, 29% during appendicectomy, and 45% in elective colorectal surgery. Most did not prolong cover beyond 24 hours postoperatively. This survey shows that the concepts governing the use of antibiotic prophylaxis have been absorbed into current surgical practice. Most surgeons used appropriate antibiotic regimens; many prefer the parenteral route of administration; most do not prolong cover beyond 24 hours.