Perioperative Systemic Antibiotics Research Articles

Microbial Colonization of Explants after Osteosynthesis in Small Animals: Incidence and Influencing Factors.

Despite recent advancements in antibiotics, hygienic measures, and peri-operative systemic antibiotics, post-operative infections in osteosynthesis remain prevalent and continue to be among the most common surgical complications, leading to delayed fracture healing, osteomyelitis, implant loosening, and loss of function. Osteosynthesis implants are routinely utilized in veterinary medicine and the current study investigates the microbial colonization of implants following osteosynthesis in small animals, along with its incidence and influencing factors. The results are analyzed in regard to correlations between infection, patient, disease progression, and radiographic images, as well as other factors that may promote infection. Seventy-one explants from sixty-five patients were examined and evaluated for microbial colonization. Factors like body weight and age, location and type of plate and additional injuries like lung lesions, the surgeon's experience, or the number of people present during the surgical procedure seem to influence the development of an infection. Of the animals, 60% showed osteolytic changes and 73.3% of those with dysfunctional mobility had an implant infection. Microorganisms were detected in almost 50% of the explants, but a clinically relevant infection was only present in five patients (7.3%), suggesting that the presence of microorganisms on an implant does not necessarily lead to treatment complications.

Evaluation of factors associated with surgical site infection in equine proximal interphalangeal joint arthrodesis: 54 cases (2010-2019).

BackgroundThe frequency of surgical site infection (SSI) following orthopaedic implant placement in horses has been reported but not compared with respect to specific antibiotic protocols administered.ObjectivesTo determine factors associated with SSI in horses undergoing proximal interphalangeal joint (PIPJ) arthrodesis including perioperative antibiotic protocols.MethodsRecords were evaluated (2010–2019), and horses undergoing PIPJ arthrodesis were identified. Patient signalment, supervising surgeon, reason for surgery, limb, implants placed, anaesthetic time, duration casting/coaptation postoperatively, antibiotic regimen and incidence/onset SSI were recorded. Bayesian and frequentist logistic regressions were used to estimate the contribution of covariates to infection occurrence.ResultsFifty‐four PIPJ arthrodeses were performed. SSI occurred in 2/54 (3.7%) on day 15,30. Arthrodesis was performed most commonly for osteoarthritis (33/54, 61.1%), fracture (11/54, 20.4%), and subluxation (5/54, 9.3%). Perioperative systemic antibiotics were administered 1–3 days (15/54, 27.8%) or > 3 days (39/54, 72.2%). Antibiotic protocols included cefazolin/gentamicin (20/54, 37%), cefazolin/gentamicin/doxycycline (14/54, 25.9%) and potassium penicillin/gentamicin (10/54, 18.5%). Regional limb perfusion was performed preoperatively 31/54 (57.4%) and postoperatively 7/54 (13%). Survival to dismissal was 98.1% (53/54 horses) with one horse euthanized due to support limb laminitis. No association was identified between antibiotic selection or duration (1–3 vs. > 3 days), pre‐operative regional antibiotic perfusion, intraoperative antibiotic lavage or anaesthetic time (< or > 3 h) and SSI; however, modelling was complicated by quasi‐complete or complete separation of the data. Bayesian analysis (but not frequentist analysis) indicated an association between post‐operative regional antibiotic perfusion and SSI. Limitations include the retrospective nature of data collection and the low rate of infection overall.ConclusionsThe prevalence of SSI in this population was lower than that in previous reports of equine orthopaedic internal fixation. There was no difference in SSI rate in cases administered systemic antibiotics for 1–3 days or >3 days, or for those horses that did or did not receive preoperative regional antibiotic perfusion.

Antibiotic therapy for the prevention of osteoradionecrosis following tooth extraction in head-and-neck cancer patients postradiotherapy: An 11-year retrospective study.

Introduction:One of the most important complications of radiotherapy (RT) for head-and-neck cancer (HNC) is osteoradionecrosis (ORN) of the jaws, which mostly arises from tooth extractions. The ORN treatment still represents a great challenge; therefore, the prevention is of paramount importance. Thus, the present study aimed to evaluate retrospectively a perioperative systemic antibiotic therapy protocol for the prevention of ORN following tooth extraction in head-and-neck patients post-3D conformal RT.Materials and Methods:A retrospective medical record review was performed considering HNC patients submitted to RT in the period between 2008 and 2019. They necessarily received oral antibiotic therapy with Clindamycin 300 mg every 8 h for 10 days, with the first dose 3 days before the tooth extraction.Results:Forty-nine patients met the study criteria, with a total of 107 teeth extracted. Regarding the 47 patients who did not develop ORN, 103 tooth extractions were identified (96.3%). Only two patients developed ORN at two adjacent teeth sites (3.7%).Conclusion:The proposed perioperative systemic antibiotic therapy protocol seems to be efficient to prevent ORN following tooth extraction in postirradiated HNC patients.

The A2B trial, antibiotic prophylaxis for excision-graft surgery in burn patients: a multicenter randomized double-blind study

BackgroundThe indication for antibiotic prophylaxis in burn patients remains highly controversial, with no consensus having been reached. The objective of antibiotic prophylaxis is to reduce the risk of postoperative local and systemic infections. Burn surgery is associated with a high incidence of bacteremia, postoperative infections, and sepsis. However, antibiotic prophylaxis exposes patients to the risk of selecting drug-resistant pathogens as well as to the adverse effects of antibiotics (i.e., Clostridium difficile colitis). The lack of data precludes any strong international recommendations regarding perioperative prophylaxis using systemic antibiotics in this setting.The goal of this project is therefore to determine whether perioperative systemic antibiotic prophylaxis can reduce the incidence of postoperative infections in burn patients.MethodsThe A2B trial is a multicenter (10 centers), prospective, randomized, double-blinded, placebo-controlled study. The trial will involve the recruitment of 506 adult burn patients with a total body surface area (TBSA) burn of between 5 and 40% and requiring at least one excision-graft surgery for deep burn injury. Participants will be randomized to receive antibiotic prophylaxis (antibiotic prophylaxis group) or a placebo (control group) 30 min before the incision of the first two surgeries. The primary outcome will be the occurrence of postoperative infections defined as postoperative sepsis and/or surgical site infection and/or graft lysis requiring a new graft within 7 days after surgery. Secondary outcomes will include mortality at day 90 postrandomization, skin graft lysis requiring a new graft procedure, postoperative bacteremia (within 48 h of surgery), postoperative sepsis, postoperative surgical site infection, number of hospitalizations until complete healing (> 95% TBSA), number of hospitalization days living without antibiotic therapy at day 28 and day 90, and multiresistant bacterial colonization or infection at day 28 and day 90.DiscussionThe trial aims to provide evidence on the efficacy and safety of antibiotic prophylaxis for excision-graft surgery in burn patients.Trial registrationClinicalTrials.gov NCT04292054. Registered on 2 March 2020

Systemic Preoperative Antibiotics with Mandible Fractures: Are They Indicated at the Time of Injury?

Mandible fractures are the most common result of facial trauma. The proximity of oral flora to the site of both the injury and resulting surgical instrumentation makes managing infection a unique challenge. The benefit of antibiotic prophylaxis at the time of surgical treatment of mandible fractures is well established. However, the routine use of antibiotics between the time of injury and surgery is of unclear benefit. We aim to define the role of antibiotics in the preoperative period: from the time of injury to surgical intervention. Demographic and clinical data were collected retrospectively on all patients who were treated for mandible fracture by the Division of Plastic and Reconstructive Surgery at our institution between 2003 and 2013. The use of both preoperative (between injury and surgery) and perioperative (at the time of surgery) systemic antibiotics was recorded along with the incidence of postoperative infections and other complications. Complete data were available for 269 patients. Of the 216 patients who received preoperative antibiotics, 22 (10%) developed an infection postoperatively. Of the 53 patients who did not receive preoperative antibiotics, 2 (4%) developed infection ( p = 0.184). Likewise, preoperative antibiotics were not significantly associated with hardware complication rates. In our retrospective review, the use of antibiotics between injury and surgical repair had no impact on postoperative infection rates. These data suggest that preoperative antibiotic use may actually be associated with an increased incidence of postoperative infection. Our results do not support the routine use of antibiotics between injury and surgical repair in patients with mandible fractures.

Are gut bacteria associated with the development of anastomotic leaks?

It has been proven in experimental and clinical studies that combined perioperative systemic antibiotic prophylaxis and prolonged nonresorbable topical antibiotics directed against common intestinal Gram-negative and Gram-positive pathogens in a mechanically cleaned bowel are effective in preventing intestinal anastomotic leak (AL). For 60 years, evidence has been accumulating that AL is caused by microbial pathogenicity. Examples are E. faecalis and P. aeruginosa, which develop the ability to breakdown collagen and/or cleave host Matrix metalloproteinase 9 (MMP9). The surgical trauma seems to trigger such complex reactions as gentotypical and phenotypical changes in commensal microbiota, turning them into tissue-destroying, leak-inducing pathogens. Investigations of further molecular mechanisms and clinical studies are ongoing. The use of antibiotics disrupts the endogenous microbiome and causes antibiotic resistance. It is therefore important to find therapies that leave the microbiome intact and target microbial virulence expression. One such approach to avoid indiscriminate elimination of all potential pathogens with simultaneous damage to protective microbiota is represented by phosphate-loaded polyethylene glycopolymers.

Do antibiotic-impregnated external ventriculostomy catheters have a low infection rate in clinical practice? A retrospective cohort study

Objective: External ventriculostomy-related infection (VRI) of cerebrospinal fluid (CSF) is a source of significant morbidity and mortality. In previous trials, antibiotic-impregnated ventricular catheters have been associated with lower incidence of CSF infections. We undertook this retrospective observational study to evaluate whether the introduction of antibiotic-impregnated external ventricular drains (EVDs) in 2004 has decreased VRI in our neurosurgical unit. Method: One hundred and fifteen patients underwent insertion of EVDs from January 2000 to March 2008. Data were collected for 99 patients with a total of 146 EVD insertions. The parameters studied were age, gender, ASA score, seniority of the surgeon, significant medical history, presence of trauma, concurrent surgeries, revisional surgery, use of peri-operative systemic antibiotic, use of antibiotic-impregnated external ventricular catheter, tunnelling of the catheter, duration of drainage and VRIs. Results: Eleven patients developed new VRI (12%). Analysis comparing infection incidence for various co-morbidities shows that systemic sepsis was associated with higher infection rates (p = 0.037). Revisional surgery (p = 0.036) and longer duration of catheterization (p = 0.001) were also found to be associated with VRI. The Standard catheters and the antibiotic-impregnated catheters had similar infection rates. The antibiotic-impregnated catheters tended to be infection-free for longer but these differences were not statistically significant. The duration of catheterization was significantly higher for the antibiotic-impregnated catheter group. In both groups, the majority of infections were caused by Gram-positive bacteria. Conclusion: Our study demonstrates that there was no statistically significant difference in the infection rates for the Standard and antibiotic-impregnated external ventriculostomy catheters. The duration of catheterization was significantly higher for the Antibiotic-impregnated catheter group. The antibiotic-impregnated catheter infections tended to occur later as compared with the Standard catheter group.

Reconstruction of Peri-implant Osseous Defects

There is a paucity of data for the effectiveness of reconstructive procedures in the treatment of peri-implantitis. The objective of this study was to compare reconstruction of peri-implant osseous defects with open flap debridement (OFD) plus porous titanium granules (PTGs) compared with OFD alone. Sixty-three patients (36 female, 27 male; mean age 58.4 y [SD 12.3]), contributing one circumferential peri-implant intraosseous defect, were included in a multinational, multicenter randomized trial using a parallel-group design. After OFD and surface decontamination using titanium brushes and hydrogen peroxide, 33 defects received PTGs. The implants were not submerged. All patients received adjunctive perioperative systemic antibiotics. The primary outcome variable (defect fill) was assessed on digitalized radiographs. Clinical measurements of probing depth (PPD), bleeding on probing (BoP), suppuration, and plaque were taken by blinded examiners. After 12 mo, the test group (OFD plus PTG) showed a mean radiographic defect fill (mesial/distal) of 3.6/3.6 mm compared with 1.1/1.0 in the control group (OFD). Differences were statistically significant in favor of the test group (P < 0.0001). The OFD plus PTG group showed a mean reduction in PPD of 2.8 mm compared with 2.6 mm in the OFD group. BoP was reduced from 89.4% to 33.3% and from 85.8% to 40.4% for the test and control groups, respectively. There was no significant difference in complete resolution of peri-implantitis (PPD ≤4 mm and no BoP at six implant sites and no further bone loss), because this finding was accomplished at 30% of implants in the test group and 23% of implants in the control group. Reconstructive surgery using PTGs resulted in significantly enhanced radiographic defect fill compared with OFD. However, limitations in the lack of ability to discern biomaterial from osseous tissue could not be verified to determine new bone formation. Similar improvements according to clinical measures were obtained after both surgical treatment modalities (ClinicalTrials.gov NCT02406001).

Antibiotic prophylaxis for preventing burn wound infection

Infection of burn wounds is a serious problem because it can delay healing, increase scarring and invasive infection may result in the death of the patient. Antibiotic prophylaxis is one of several interventions that may prevent burn wound infection and protect the burned patient from invasive infections. To assess the effects of antibiotic prophylaxis on rates of burn wound infection. In January 2013 we searched the Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid MEDLINE - In-Process & Other Non-Indexed Citations (2013); Ovid EMBASE; EBSCO CINAHL and reference lists of relevant articles. There were no restrictions with respect to language, date of publication or study setting. All randomised controlled trials (RCTs) that evaluated the efficacy and safety of antibiotic prophylaxis for the prevention of BWI. Quasi-randomised studies were excluded. Two review authors independently selected studies, assessed the risk of bias, and extracted relevant data. Risk ratio (RR) and mean difference (MD) were estimated for dichotomous data and continuous data, respectively. When sufficient numbers of comparable RCTs were available, trials were pooled in a meta-analysis to estimate the combined effect. This review includes 36 RCTs (2117 participants); twenty six (72%) evaluated topical antibiotics, seven evaluated systemic antibiotics (four of these administered the antibiotic perioperatively and three administered upon hospital admission or during routine treatment), two evaluated prophylaxis with non absorbable antibiotics, and one evaluated local antibiotics administered via the airway.The 11 trials (645 participants) that evaluated topical prophylaxis with silver sulfadiazine were pooled in a meta analysis. There was a statistically significant increase in burn wound infection associated with silver sulfadiazine compared with dressings/skin substitute (OR = 1.87; 95% CI: 1.09 to 3.19, I(2) = 0%). These trials were at high, or unclear, risk of bias. Silver sulfadiazine was also associated with significantly longer length of hospital stay compared with dressings/skin substitute (MD = 2.11 days; 95% CI: 1.93 to 2.28).Systemic antibiotic prophylaxis in non-surgical patients was evaluated in three trials (119 participants) and there was no evidence of an effect on rates of burn wound infection. Systemic antibiotics (trimethoprim-sulfamethoxazole) were associated with a significant reduction in pneumonia (only one trial, 40 participants) (RR = 0.18; 95% CI: 0.05 to 0.72) but not sepsis (two trials 59 participants) (RR = 0.43; 95% CI: 0.12 to 1.61).Perioperative systemic antibiotic prophylaxis had no effect on any of the outcomes of this review.Selective decontamination of the digestive tract with non-absorbable antibiotics had no significant effect on rates of all types of infection (2 trials, 140 participants). Moreover, there was a statistically significant increase in rates of MRSA associated with use of non-absorbable antibiotics plus cefotaxime compared with placebo (RR = 2.22; 95% CI: 1.21 to 4.07).There was no evidence of a difference in mortality or rates of sepsis with local airway antibiotic prophylaxis compared with placebo (only one trial, 30 participants). The conclusions we are able to draw regarding the effects of prophylactic antibiotics in people with burns are limited by the volume and quality of the existing research (largely small numbers of small studies at unclear or high risk of bias for each comparison). The largest volume of evidence suggests that topical silver sulfadiazine is associated with a significant increase in rates of burn wound infection and increased length of hospital stay compared with dressings or skin substitutes; this evidence is at unclear or high risk of bias. Currently the effects of other forms of antibiotic prophylaxis on burn wound infection are unclear. One small study reported a reduction in incidence of pneumonia associated with a specific systematic antibiotic regimen.

Antibiotics and Antiseptics to Prevent Infection in Cardiac Rhythm Management Device Implantation Surgery

Surgical site infections (SSIs) resulting from cardiac implantable electronic device (CIED) implantation cause significant morbidity and mortality, and are increasing at a disproportionately higher rate than the rate of CIED implantation. The prophylactic administration of antibiotics and antiseptics can reduce this infection rate. The objective of this systematic review and meta-analysis was to determine whether the prophylactic administration of antibiotics and antiseptics in patients undergoing CIED implantation reduces the incidence of SSI in randomized controlled trials. We searched the Cochrane Wounds Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 2), Ovid MEDLINE, Ovid EMBASE, and EBSCO CINAHL. No date or language restrictions were applied. Two review authors independently screened papers for inclusion, assessed risk of bias, and extracted data using a data collection form. Data were pooled where appropriate. Fifteen studies (3,970 participants) were included in this review. For patients undergoing a CIED implant, perioperative systemic antibiotics (PSA) plus antiseptics delivered 1 hour before the procedure significantly reduced the incidence of SSI compared with no antibiotics (risk ratio [RR] 0.13; 95% confidence interval [CI] 0.05-0.36; P value < 0.00001). Furthermore, PSA plus antiseptics significantly reduced the incidence of postoperative infection compared to antibiotics delivered postoperatively (RR 0.14; 95% CI 0.03-0.60; P value 0.008). The evidence strongly suggests that antibiotic prophylaxis within 1 hour before CIED implantation is effective at reducing SSI.

Prevention of Surgical Site Infections in Bone and Joint Procedures

There is strong evidence that preoperative nasal S. aureus screening/decolonization will significantly reduce surgical site infections (SSIs) after joint prostheses implantation. There is some evidence that antibiotic-containing bone cement may lower SSI rates. Timely administration of perioperative systemic antibiotic prophylaxis is recommended for patients with implants who are undergoing dental treatment, urogenital surgery, upper endoscopy, sigmoidoscopy, or colonoscopy. Advanced skin disinfection by chlorhexidine-gluconate-impregnated cloths may be protective. There is evidence that clippers are favored for hair removal, rather than razors, but no significant advantage, as compared with other modes of hair removal, has been found. Antibiotic-coated intramedullary nails and antibiotic-impregnated bone grafts may be useful for the treatment of chronic bone infections. No recommendation can be made for wound dressing types. Laminar air flow systems do not seem to prevent SSI but may even cause harm, instead. There is a strong association between the annual number of surgical procedures and low SSI rates.

Systemic Perioperative Antibiotic Prophylaxis May Improve Skin Autograft Survival in Patients With Acute Burns

Skin autograft is the most important definitive treatment for acute-deep burns. Wound infection is the most important cause of autograft loss. Prior clinical studies have not shown any significant difference in the autograft survival rate and the use of perioperative systemic antibiotics. Their study assesses the potential benefit of systemic antibiotics in this setting, especially when topical antibiotics or artificial skin products are not readily available. The authors designed a prospective, randomized study in a cohort of patients with acute burns to assess the hypothesis that the use of systemic antibiotic prophylaxis affects the rate of skin autograft survival. Enrolled patients could have more than one autograft procedure done. These patients were randomized for each surgical procedure. The outcome measurement was autograft survival rate between the two groups. From October 2001 to October 2006, 77 patients were enrolled with a mean age of 41.7 years (SD +/- 19.4) and a mean skin total burn body surface area of 21.8 (SD +/- 23). The experimental group had 44 autograft procedures with systemic antibiotics (AP) and the control group had 46 procedures without antibiotics (NP). The rate of autograft survival for the AP group was 97% and for the NP group was 87% (P < .01) There was a partial autograft loss in 10 procedures (23%) in the AP group and 23 procedures (50%) in the NP group (P < .01). Patients with acute deep burns treated with autografts may benefit from systemic perioperative antibiotics prophylaxis, as antibiotics seem to be associated with increase autograft survival rate. The risk of colonization in other parts of the body with multidrug resistant bacteria warrants further study.

Locally Administered Antibiotics for Prophylaxis Against Surgical Wound Infection

Background: Currently, the standard for prophylaxis against surgical infection consists of perioperative systemic antibiotics. In this study, we investigated the relative efficacy of various methods of antibiotic delivery for the prevention of surgical wound infections. We hypothesized that sustained release of local antibiotics inside the wound cavity by a drug delivery system would be more effective than systemically administered antibiotics. Methods: Using a rat model, we inoculated a surgical wound in the quadriceps muscle with 8.0 × 105 colony-forming units of Staphylococcus aureus and then administered one of seven types of treatment: no treatment (control), bacitracin irrigation, calcium sulfate flakes, systemic gentamicin, local aqueous gentamicin, local gentamicin-loaded calcium sulfate flakes, and a combination of local gentamicin-loaded calcium sulfate and systemic gentamicin. The seven treatment groups consisted of ten rats each. To further evaluate a trend, the group treated with systemic gentamicin and the one treated with local gentamicin solution were extended to include twenty-five and twenty-seven rats, respectively. At forty-eight hours postoperatively, specimens from the wounds were obtained for quantitative culture. Results: The control group, the group treated with bacitracin irrigation, and the one treated with plain calcium sulfate had very high bacterial counts and high mortality rates while the groups treated with gentamicin had low bacterial counts and a 100% survival rate. Local gentamicin was significantly more effective than systemic gentamicin in reducing bacterial counts. Conclusions: The gentamicin-loaded calcium sulfate flakes did not result in bacterial counts that were significantly lower than those following systemic administration of gentamicin, which refuted our hypothesis. However, gentamicin solution injected directly into the closed wound did result in levels of bacteria that were significantly lower than those following treatment with the systemic gentamicin. Clinical Relevance: We believe that a high initial concentration of locally applied antibiotic inside the wound effectively kills bacteria present in the wound cavity, where systemic antibiotics have poor penetration, suggesting that this method of antibiotic administration may be a desirable adjunct for prophylaxis against infection in surgical wounds.

Locally Administered Antibiotics for Prophylaxis Against Surgical Wound Infection

Currently, the standard for prophylaxis against surgical infection consists of perioperative systemic antibiotics. In this study, we investigated the relative efficacy of various methods of antibiotic delivery for the prevention of surgical wound infections. We hypothesized that sustained release of local antibiotics inside the wound cavity by a drug delivery system would be more effective than systemically administered antibiotics. Using a rat model, we inoculated a surgical wound in the quadriceps muscle with 8.0 x 10(5) colony-forming units of Staphylococcus aureus and then administered one of seven types of treatment: no treatment (control), bacitracin irrigation, calcium sulfate flakes, systemic gentamicin, local aqueous gentamicin, local gentamicin-loaded calcium sulfate flakes, and a combination of local gentamicin-loaded calcium sulfate and systemic gentamicin. The seven treatment groups consisted of ten rats each. To further evaluate a trend, the group treated with systemic gentamicin and the one treated with local gentamicin solution were extended to include twenty-five and twenty-seven rats, respectively. At forty-eight hours postoperatively, specimens from the wounds were obtained for quantitative culture. The control group, the group treated with bacitracin irrigation, and the one treated with plain calcium sulfate had very high bacterial counts and high mortality rates while the groups treated with gentamicin had low bacterial counts and a 100% survival rate. Local gentamicin was significantly more effective than systemic gentamicin in reducing bacterial counts. The gentamicin-loaded calcium sulfate flakes did not result in bacterial counts that were significantly lower than those following systemic administration of gentamicin, which refuted our hypothesis. However, gentamicin solution injected directly into the closed wound did result in levels of bacteria that were significantly lower than those following treatment with the systemic gentamicin.

CEFUROXIME-IMPREGNATED CEMENT IN PRIMARY TOTAL KNEE ARTHROPLASTY

A prospective, randomized study was conducted to evaluate the efficacy of cefuroxime-impregnated cement in the prevention of deep infection after primary total knee arthroplasties performed without so-called clean-air measures, such as laminar flow and body-exhaust suits. Three hundred and forty primary total knee arthroplasties were performed with cementless fixation of the femoral component and cement fixation of the patellar and tibial components. The knees were randomly divided into two groups. In Group 1 (178 knees), cefuroxime-impregnated cement was used for fixation, whereas in Group 2 (162 knees), the cement did not contain cefuroxime. There was no significant difference between the two groups regarding demographic variables, the preoperative or postoperative knee score, the duration of the operation or of the use of the tourniquet, or the amount of blood transfused perioperatively. The average duration of follow-up was forty-nine months (range, twenty-six to eighty months). No deep infection developed in the 178 knees in Group 1, whereas a deep infection developed in five (3.1%) of the 162 knees in Group 2 (p = 0.0238). Two superficial wound infections developed in each group. Cefuroxime-impregnated cement was shown to be effective in the prevention of early to intermediate deep infection after primary total knee arthroplasty performed with use of perioperative systemic antibiotic prophylaxis but no so-called clean-air measures.

Surgical wound infection in renal transplantation: Outcome data in 102 consecutive patients without perioperative systemic antibiotic coverage: Stephen RN, Munschauer CE, Kumar MS. Arch Surg 132:1315, 1997

Surgical wound infection in renal transplantation: Outcome data in 102 consecutive patients without perioperative systemic antibiotic coverage: Stephen RN, Munschauer CE, Kumar MS. Arch Surg 132:1315, 1997

Surgical wound infection in renal transplantation: outcome data in 102 consecutive patients without perioperative systemic antibiotic coverage.

The incidence of surgical wound infection in the presence of immunosuppression has been reported in the literature to approach 7%. Perioperative systemic antibiotic therapy is routinely used to reduce the occurrence of wound infections. This therapy is not without complications, including adverse effects and development of resistant strains. Surgical wound infection rates during the first 100 days after renal transplantation were studied in 102 consecutive patients. Eighty-one patients underwent cadaveric transplantation and 21 patients underwent living-related donor transplantation from February 1, 1991, to January 1, 1992. No systemic perioperative antibiotic coverage was used, but local antibiotic irrigation was part of the perioperative protocol. Hahnemann University Hospital, Philadelphia, Pa, is a large, tertiary care center. Patients were initially hospitalized and were discharged during the 100-day follow-up period based on clinical status and improvement in renal function. Twenty-seven (25%) of 102 patients had diabetes mellitus. Induction immunosuppression consisted of azathioprine, prednisone, and anitlymphocyte globulin, while maintenance immunosuppression consisted of azathioprine, prednisone, and cyclosporine. Acute allograft rejection episodes were treated with steroids and/or OKT3 (Ortho Pharmaceutical Group, Raritan, NJ). Two surgical wound infections (2%) occurred. In both, infection was superficial, resolving with wound drainage and intravenous antibiotics. The surgical wound infection rate was not significantly affected by age, sex, allograft source, or presence of diabetes mellitus. Despite immunosuppression, the incidence of surgical wound infection was minimal, comparing favorably to rates reported for renal transplantation with the use of systemic antibiotics. Possible explanations for the low incidence of surgical wound infections include local wound irrigation, meticulous hemostasis, improved organ procurement techniques, and continuity in perioperative care.

Once May Be Enough

Methods to prevent postprostatectomy wound infections in patients having open prostatectomy, and bacteriuria in those having open or transurethral prostatectomy, are legion and controversial. Virtually every new antibiotic or topical antiseptic has been subjected to a longor short-course study attempting to show prophylactic or treatment efficacy, all too often in poorly controlled studies. There are acceptable data in the literature to support the concepts that prophylactic perioperative systemic antibiotics, with spectra covering the common urinary pathogens, can significantly decrease bacteriuria, bacteremia, pyrexia, wound infections, and hospital stay in catheterized patients with sterile urine.1 The choice of prophylactic antibiotic is not absolutely critical, with many broad-spectrum agents providing similar results. This approach is not unanimously endorsed for such patients, although much more controversy exists regarding the need for any prophylaxis in noncatheterized patients with sterile urine.2 Patients with infected urine, however, require treatment with organism-susceptible systemic agents prior to surgical therapy to sterilize the urine and reduce the high rate of infectious complications.2,3 The concept of preoperative bladder irrigation with one of various antibacterial solutions is not new, and, in fact, the use of povidone-iodine has been reported previously to be useful if the concentration is 2% or greater and irrigations are done the night before and morning of surgery.4,5 The addition that the article by Richter et al in this issue makes is that one irrigation of povidone-iodine immediately prior to open prostatectomy produces similar results in terms of reducing b cteriuria wound infections. The study is not randomiz d, and all patients were treated with organismsensitive but differing systemic antibiotics. However, assuming, as best as can be determined from the data presen d, that the patient populations are comparable, the data in this study are compelling. Indeed, the addition of a povidone-iodine irrigation once preoperat v ly seems simple and effective. Relatively unnoticed, but perhaps the more importa t concept in this and other similar studies is the queue these patients must endure prior to definitive surgery. The patients themselves and/or the system delays car until they are in urinary retention. An indwelling ca heter is required, and then the patients wait an average of 50 days to have surgery. Whereas in some he lthcare systems, prostatectomy may be initiated too early-before a progressive natural history in the particular patient is established-in others it appear to be late-after the patient requires persistent bladder drainage. The data available clearly show that uninfec ed patients have fewer complications; us it seems intuitive that it would be in the patients' best interests to treat them surgically before they require constant drainage and thus become colonized, shortly after the necessity of catheter drainage b comes evi ent, or as part of a program of clean in ermittent catheterization in an attempt to prevent colonization in patients who do require long-term cat eterization prior to surgery. Perhaps the one-time povidone-iodine instillation advocated would be best used in thes patients.

Perioperative systemic antibiotics for prophylaxis of infections in breast surgery: sulbactam/ampicillin versus mezlocillin/oxacillin

In a prospective, randomized, open trial, efficacy of one dose of sulbactam/ampicillin (1 g:2 g) was compared to three doses of mezlocillin/oxacillin (2 g:1 g), starting with induction of anesthesia in 80 breast surgery patients with an increased risk of postoperative infection. No infections at the site of operation were seen in either group. Fever due to postoperative pulmonary complications occurred in one patient in the sulbactam/ ampicillin group. The only side effect was a moderate exanthema observed in one patient in the mezlocillin/oxacillin group. In this study of the prophylaxis of patients with an increased risk of postoperative infections having the potential to jeopardize the results of surgery, a single dose of sulbactam/ampicillin was as effective as a short term course of three doses of mezlocillin/oxacillin.

Canine model for long-term evaluation of prosthetic mitral valves

The evaluation of mechanical prosthetic heart valves would be aided by a more satisfactory animal model. For acute assessment, a variety of animals have been used, but for chronic studies, only larger animals (pigs, calves, baboons) have been employed, creating an expensive model with laboratory management difficulties. Previously, the use of dogs for chronic evaluation has been unsatisfactory because of the frequent occurrence of early sepsis and valve-related thrombotic deaths. We have modified our existing acute dog protocol to produce a successful chronic model. Our model employs perioperative systemic antibiotics, short cardiopulmonary bypass period (range 35–60 min), a minimum of perioperative intravenous lines, postoperative anticoagulation therapy, and strict postoperative antiseptic technique for blood sampling. To evaluate this model, 11 consecutive mongrel dogs underwent mitral valve replacement with either a standard Dacron sewing skirt or a newly devised carbon-coated Teflon sewing skirt No. 23 mm Bjork-Shiley Convexo Concave (CC) prosthetic valve. Nine animals (82%) survived and were evaluated after a predetermined observation interval of either 3 or 6 months for valve function, pannus formation, and possible carbon particle migration. At sacrifice, all animals had good hemodynamics and valve function, minimal pannus formation and no carbon washout. Consequently, this model provides a relatively inexpensive, reproducible method of chronic in vivo evaluation of prosthetic valve modifications.