Cefuroxime, rifampicin and pulse lavage in decontamination of allograft bone

Experience with Tissue Bank Services in 2014 and 2020 in Turku, Finland

BACKGROUND

The objective of a musculoskeletal tissue bank is to collect, test, store, and provide musculoskeletal tissue allografts required in orthopedic procedures. Strict exclusion criteria are followed when selecting suitable cadaver musculoskeletal tissue donors, and the allografts are procured under sterile conditions to avoid bacterial contamination. Tissue banking in Turku, Finland, began in 1972, and tissue bank services were last reviewed in 2003. This study aimed to review the operation of the musculoskeletal tissue bank in Turku, Finland, between 2014 and 2020 and to analyze the number, types, and contamination rate of the allografts procured from the cadaver donors. Potential donor-related factors causing bacterial contamination of the allografts and whether potential musculoskeletal tissue donors were overlooked among multiorgan donors were also studied.

METHODS

A retrospective review of all cadaver musculoskeletal tissue donors used in the Hospital District of Southwest Finland Tyks Orto Musculoskeletal Tissue Bank during the study period was conducted, and data on the procured allograft was collected and presented. The donors were selected among patients treated in the intensive care unit (ICU) of Turku University Hospital (TYKS).

RESULTS

A total of 28 cadaver donors were used, and 636 allografts were procured between 2014 and 2020. The bacterial contamination rate was 2.5%, which was lower than that in the previous international literature. The median treatment time in the ICU was significantly longer, and the median value of the highest C-reactive protein level was significantly higher in the group of donors with positive allograft bacterial cultures.

CONCLUSIONS

The bacterial contamination rate in the tissue bank was low on an international scale. Some suitable musculoskeletal tissue donors were overlooked among multiorgan donors.

The Practices and Attitudes of Saudi Plastic Surgeons in Managing Contaminated Autologous Grafts

Background:

The use of autologous grafts is a standard reconstructive option in plastic surgery. The absence of a well-established protocol for decontamination after accidental contamination increases the risk of postoperative infection. We aimed to explore the current practice and decontamination methods among Saudi plastic surgeons. This would help develop a well-established, unified method of decontamination intraoperatively.

Methods:

A validated self-administered questionnaire cross-sectional study was conducted in February 2022. The questionnaire was distributed through social media to all board-certified plastic surgeons in Saudi Arabia. The questionnaire was designed to obtain data on incidents, treatment preferences, and management of autograft contamination.

Results:

A total sample size of 61 participants was included, with an overall response rate of 64.58%. Out of the 61 respondents, 73.8% (n = 45) had previously experienced graft contamination. Regarding the methods of graft contamination, the most common way was accidentally dropping the graft on the floor (39.7%, n = 25). The majority of the surgeons answered that they decontaminated the graft using povidone-iodine (44.6%, n = 29) and then used it (45.9%, n = 28). The lower extremity area was the most common anatomical location having surgery at the time of the graft contamination, accounting for 32.5% of the cases (n = 25).

Conclusions:

Our study indicates that graft contamination is a common occurrence among our population, but we lack national guidelines on dealing with these situations. Although most responders used adequate decontamination methods, the lack of standardization could pose a risk to patients.

Bacterial contamination of bone allografts in the tissue banks: a systematic review and meta-analysis

BACKGROUND

Bone allografts are harvested and transplanted under sterile conditions. However, the risk of bacterial contamination of grafts during these processes is a health concern. Bioburden testing and bacterial contamination detection are conducted to ensure allograft sterility.

AIM

The present study aimed to determine the incidence of bacterial contamination in bone allografts based on different classifications.

METHODS

PROSPERO registration number was received for the study. Systematic searches were conducted in PubMed and EMBASE databases with relevant keywords from January 2000 to March 2021. After choosing related studies according to the PRISMA flow diagram, Stata software was used for data analysis. We considered I² ˃ 50% as heterogeneity between studies.

FINDINGS

The overall incidence of bacterial contamination was 12.6% (95% CI 0.100, 0.152) among 19,805 bone allografts of 17 studies. The bacterial contamination rate among bone allografts was 10.8% before 2010 and 14.7% in 2010-March 2021. The contamination frequency in Asia, Europe, and Australia was 11.5%, 14.3%, and 5.2%, respectively. Bone contamination rates were higher in cadaver donors (19.9%), retrieval time sampling (13.5%), and swab samples (13.2%) compared to those in living donors (7.5%), implantation time sampling (6.9%), and bone fragments cultures (6.3%). Bacterial contamination was recovered 24.4%, 19.7%, 13.2%, and 21% from tibia, fibula, femoral, and other bones, respectively. Staphylococcus spp. was the predominant isolated bacteria from bones (63.2% of all isolated genera), followed by Propionibacterium spp. (10.6%).

CONCLUSION

The high contamination of bone allografts is a health concern, indicating the need for more health monitoring and improvement of standards.

Back to Basics: Autologous Tissue: 1.5 www.aornjournal.org/content/cme

Perioperative personnel manage autologous tissue when they care for patients undergoing procedures requiring the use of bone, soft tissue, or other autologous tissue to repair or replace defects. Use of autologous tissue can minimize the risk of rejection, disease transfer, and infection compared with the use of artificial materials. There are important steps to follow when handling autologous tissue to ensure it is safe for replantation and does not become contaminated. This Back to Basics article provides strategies for managing some types of autologous tissue, including bone flaps, parathyroid tissue, skin grafts, and veins. Tissue management strategies include creating strict documentation policies, standardizing processes and communication, and implementing routine audits to assess compliance.

Accidental dropping or misplacement of free flaps

OBJECTIVES/HYPOTHESIS

Standard operating procedures have been developed in many surgical practices to ensure quality of care as it relates to specimens removed from the body. Most of these specimens are sent to pathology. Some, such as calvarial bone harvested during craniotomy are replaced in the body. Free tissue transfer involves harvesting tissue from one body site, storage for a variable period of time outside of the body, and then insertion in another location. As with any system there is ample opportunity for accidental "misplacement." We undertook a multi-institutional study to examine the incidence, etiology, and opportunity for process improvement.

STUDY DESIGN

Retrospective review.

METHODS

A retrospective review was performed at five institutions (8,382 free flaps).

RESULTS

Thirteen (0.15%) flaps were dropped or wrapped in a towel/sponge and placed in a waste bucket. Eight radial forearm, three fibula, one latissimus dorsi, and one anterolateral thigh flap were misplaced. All flaps were retrieved, washed in saline/betadine, and implanted into the patient. All flaps survived; no altered outcomes were encountered. The etiology of the misplacement of the free tissue from the sterile field included miscommunication among nursing staff (seven), miscommunication among medical staff (two), and dropping the flap (four). As a result of these events, changes in the handling procedures were instituted including standard labeling methodologies and communication strategies.

CONCLUSIONS

Inadvertent misplacement of free tissue from the sterile field does occur in a sporadic fashion. Process improvement evaluation at all institutions led to improved strategies for prevention. No long-lasting altered outcomes were encountered.

LEVEL OF EVIDENCE

4

Time-dependent effects of chlorhexidine soaks on grossly contaminated bone

OBJECTIVE

The purpose of this study was to quantify the reduction in the bacterial burden of grossly contaminated bone segments using different chlorhexidine (CHL) solutions. We hypothesized that 4% CHL would be the most efficient decontaminate.

METHODS

Fifty-four bone segments were harvested from fresh-frozen porcine legs. Each specimen was dropped onto a Mueller-Hinton medium that was inoculated with Staphylococcus aureus (lux). These genetically engineered bacteria emit photons in proportion to their number, allowing for quantification. The segments were retrieved after 5 seconds of exposure. Baseline imaging provided the initial bacterial load. An equal number of specimens were soaked in normal saline (NS), 2%CHL, or 4%CHL. Specimen reimaging was completed at the 5-, 10-, 20-, 30-, and 60-minute marks.

RESULTS

The average bacterial count on the bone segments were 2.18 × 10(7) for NS, 2.31 × 10(7) for 2%CHL, and 2.00 × 10(7) for 4%CHL. The percent reduction in bacterial counts at the 5-, 10-, 20-, 30-, and 60-minute marks were NS: 0%, 0%, 0%, 29.84%, 72.23%; 2%CHL: 93.09%, 98.16%, 99.21%, 99.63%, 99.81%; 4%CHL: 94.32%, 97.60%, 99.25%, 99.63%, 99.82%. At all time intervals, there was a significant difference between the 2%CHL and 4%CHL groups compared with the NS group (P < 0.0001) and no difference between the 2%CHL and 4%CHL groups.

CONCLUSIONS

This study provides new data supporting the use of CHL to decontaminate grossly soiled bone segments. To maximize efficiency and decrease potential untoward effects, the authors recommend 20-minute soaks using 2% CHL for contaminated bone segments.

Pulse-lavage washing is an effective method for defatting of morselized allograft bone in the operating theater

BACKGROUND AND PURPOSE

Incorporation of fresh-frozen allograft bone and safety aspects associated with this procedure can be improved by removing blood and lipids from the bone. We investigated in a quantitative manner how efficient pulse lavage might be for removal of adipose tissue from morselized allograft bone.

METHODS

Depending on the study, the washing was performed with an average of 0.8 L or 1.6 L of sterile saline at room temperature. Fat content of the morselized bone samples was determined using hexane elution. The efficiency of pulse lavage alone was compared with that after an additional wash in 12 L of warm water (55 degrees C). Unprocessed controls were also included for comparison.

RESULTS

Pulse lavage with 0.8 L saline alone removed 80% of the fat from the bone, whereas 95% of the fat was removed when washing was performed with 1.6 L of saline. The cleansing efficacy was improved further when an additional wash with warm water was used.

INTERPRETATION

Our results indicate that pulse-lavage washing alone at room temperature is an effective method for defatting of morselized allograft bone, but an additional wash with warm water improves the cleansing efficiency. Pulse lavage is easily available and simple to use in the operating theater.

Autogenous particulate bone collected with a piezo-electric surgical device and bone trap: a microbiological and histomorphometric study

The aims of this study were to determine the microbiological and particle size characteristics of particulate bone collected with a piezosurgery device and bone trap, and to reduce bacterial contamination after treatment of debris with rifamycin SV. Samples were taken from 10 patients who underwent surgical extraction of their third lower molars. The ostectomy was performed with a piezosurgery device, and the debris was collected with a surgical aspiration set equipped with a bone trap. Two aliquots were taken from each sample, one of which was treated with rifamycin SV. The second aliquot, used as a control, was treated with a physiological solution. In the samples immersed in antibiotic solution, there was a statistically significant (P<0.005) reduction in bacterial contamination. The stringent protocol followed in this study has proved valid for collection of material, and treatment with rifamycin SV was found to reduce bacterial contamination in collected material.

When the Bone Flap Hits the Floor

OBJECTIVE:

There is no published data in the neurosurgical literature describing the incidence, treatment, or outcome of contaminating a bone flap. We reviewed our departmental experience to determine methods of prevention and assess our treatment strategies.

METHODS:

We retrospectively reviewed all incidents of dropped bone flaps during a craniotomy at a single medical center during a 16-year period. In addition, a questionnaire was mailed to neurosurgeons in the United States and abroad asking their own experience and method of management.

RESULTS:

Fourteen incidents of dropped bone flaps occurred during a 16-year period. Follow-up varied from 2 to 176 months. The bone flap was dropped while elevating the bone (n = 4), when handing the bone off the field (n = 4), and during plating (n = 4). The context was unknown in two cases. Management included soaking the flap in betadine and/or antibiotic solution (n = 8), autoclaving (n = 2), or discarding the bone flap and replacing with a mesh cranioplasty (n = 3). The treatment remains unknown in one case. No instances of infection were noted in follow-up. In response to the survey, 66% (33 out of 50) of the polled neurosurgeons had experienced this complication during their practice, and 83% would replace the bone flap after disinfection.

CONCLUSION:

Dropping a bone flap during neurosurgery remains an uncommon but preventable complication. Treatment options include discarding the bone followed by cranioplasty versus replacing the bone after treatment with antibiotic irrigation, betadine, and/or autoclaving. Replacement after disinfection is an appropriate option for contaminated bone flaps that avoids the expense and time of cranioplasty.