Borate bonds-containing pH-responsive chitosan hydrogel for postoperative tumor recurrence and wound infection prevention.

Chitosan has been widely used in biomedical fields due to its good antibacterial properties, excellent biocompatibility, and biodegradability. In this study, a pH-responsive and self-healing hydrogel was synthesized from 3-carboxyphenylboronic acid grafted with chitosan (CS-BA) and polyvinyl alcohol (PVA). The dynamic boronic ester bonds and intermolecular hydrogen bonds are responsible for the hydrogel formation. By changing the mass ratio of CS-BA and PVA, the tensile stress and compressive stress of hydrogel can controlled in the range of 0.61 kPa - 0.74 kPa and 295.28 kPa - 1108.1 kPa, respectively. After doping with tannic acid (TA)/iron nanocomplex (TAFe), the hydrogel successful killed tumor cells through the near infrared laser-induced photothermal conversion and the TAFe-triggered reactive oxygen species generation. Moreover, the photothermal conversion of the hydrogel and the antibacterial effect of CS and TA give the hydrogel a good antibacterial effect. The CS-BA/PVA/TAFe hydrogel exhibit good in vivo and in vitro anti-tumor recurrence and antibacterial ability, and therefore has the potential to be used as a powerful tool for the prevention of local tumor recurrence and bacterial infection after surgery.

Preventive Efficacy of Antibiotics after Impacted Mandibular Third Molar Surgery.

OBJECTIVE: To explore the preventive efficacy of antibiotics following surgical removal of the impacted mandibular third molars and screen the potential risk factors. STUDY DESIGN: A cohort trial. Place and Duration of the Study: Department of Oral and Maxillofacial Surgery, Zhejiang University School of Medicine, Stomatology Hospital, Hangzhou, China, from August 2021 to 2022. METHODOLOGY: Cases with impacted mandibular third molar were divided into two groups based on antibiotics use. The primary outcome variable post-operative infection, secondary clinical parameter analgesics intake, and other variables (the operative time, the history of pericoronitis, and wound closure) were documented. RESULTS: The post-operative infections occurred in 3.64% (n = 12) of the 330 cases (n = 330); 3.01% in the antibiotic group (n = 166) and 4.27% in the control group (n = 164, OR = 1.44, 95% CI: 0.49 to 4.06; p = 0.54). Concerning secondary outcome measures, the analgesics that the antibiotic group took was 5.40, and the control group took was 5.95 (95% CI = -0.21 to 1.30; p = 0.16). For those with post-operative infections, the average operative time was 22.83 minutes, whereas for those without post-operative infections it was 14.87 minutes (95% CI = -0.26 to 15.67; p = 0.04). When the operative time was greater than or equal to 15 minutes, it was related to more analgesics use (95% CI: -0.43 to 1.93; p <0.05), also was the history of pericoronitis (95% CI = 0.04 to 1.54; p = 0.04). CONCLUSION: Antibiotics are unnecessary for preventing post-operative infections or minimising analgesic requirements following extraction of the impacted mandibular third molars; operative time and pericoronitis showed a suppressive influence on post-operative recovery. KEY WORDS: Impacted molars, Antibiotics, Analgesics, Operative time, Pericoronitis.

Antibiotic treatment after appendectomy for acute complicated appendicitis to prevent intrabdominal abscess and wound infections.

INTRODUCTION: The purpose of this analysis was to investigate the most appropriate duration of postoperative antibiotic treatment to minimize the incidence of intraabdominal abscesses and wound infections in patients with complicated appendicitis. MATERIALS AND METHODS: In this retrospective study, which included 396 adult patients who underwent appendectomy for complicated appendicitis between January 2010 and December 2020 at the University Hospital Erlangen, patients were classified into two groups based on the duration of their postoperative antibiotic intake: ≤ 3 postoperative days (group 1) vs. ≥ 4 postoperative days (group 2). The incidence of postoperative intraabdominal abscesses and wound infections were compared between the groups. Additionally, multivariate risk factor analysis for the occurrence of intraabdominal abscesses and wound infections was performed. RESULTS: The two groups contained 226 and 170 patients, respectively. The incidence of postoperative intraabdominal abscesses (2% vs. 3%, p = 0.507) and wound infections (3% vs. 6%, p = 0.080) did not differ significantly between the groups. Multivariate analysis revealed that an additional cecum resection (OR 5.5 (95% CI 1.4-21.5), p = 0.014) was an independent risk factor for intraabdominal abscesses. A higher BMI (OR 5.9 (95% CI 1.2-29.2), p = 0.030) and conversion to an open procedure (OR 5.2 (95% CI 1.4-20.0), p = 0.016) were identified as independent risk factors for wound infections. CONCLUSION: The duration of postoperative antibiotic therapy does not appear to influence the incidence of postoperative intraabdominal abscesses and wound infections. Therefore, short-term postoperative antibiotic treatment should be preferred.

Superiority trial for the development of an ideal method for the closure of midline abdominal wall incisions to reduce the incidence of wound complications after elective gastroenterological surgery: study protocol for a randomized controlled trial.

BACKGROUND: The recent guidelines from the European and American Hernia Societies recommend a continuous small-bite suturing technique with slowly absorbable sutures for fascial closure of midline abdominal wall incisions to reduce the incidence of wound complications, especially for incisional hernia. However, this is based on low-certainty evidence. We could not find any recommendations for skin closure. The wound closure technique is an important determinant of the risk of wound complications, and a comprehensive approach to prevent wound complications should be developed. METHODS: We propose a single-institute, prospective, randomized, blinded-endpoint trial to assess the superiority of the combination of continuous suturing of the fascia without peritoneal closure and continuous suturing of the subcuticular tissue (study group) over that of interrupted suturing of the fascia together with the peritoneum and interrupted suturing of the subcuticular tissue (control group) for reducing the incidence of midline abdominal wall incision wound complications after elective gastroenterological surgery with a clean-contaminated wound. Permuted-block randomization with an allocation ratio of 1:1 and blocking will be used. We hypothesize that the study group will show a 50% reduction in the incidence of wound complications. The target number of cases is set at 284. The primary outcome is the incidence of wound complications, including incisional surgical site infection, hemorrhage, seroma, wound dehiscence within 30 days after surgery, and incisional hernia at approximately 1 year after surgery. DISCUSSION: This trial will provide initial evidence on the ideal combination of fascial and skin closure for midline abdominal wall incision to reduce the incidence of overall postoperative wound complications after gastroenterological surgery with a clean-contaminated wound. This trial is expected to generate high-quality evidence that supports the current guidelines for the closure of abdominal wall incisions from the European and American Hernia Societies and to contribute to their next updates. TRIAL REGISTRATION: UMIN-CTR UMIN000048442. Registered on 1 August 2022. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000055205.

Innovative Vancomycin-Loaded Hydrogel-Based Systems - New Opportunities for the Antibiotic Therapy.

Purpose: Surgical site infections pose a significant challenge for medical services. Systemic antibiotics may be insufficient in preventing bacterial biofilm development. With the local administration of antibiotics, it is easier to minimize possible complications, achieve drugs' higher concentration at the injured site, as well as provide their more sustained release. Therefore, the main objective of the proposed herein studies was the fabrication and characterization of innovative hydrogel-based composites for local vancomycin (VAN) therapy. Methods: Presented systems are composed of ionically gelled chitosan particles loaded with vancomycin, embedded into biomimetic collagen/chitosan/hyaluronic acid-based hydrogels crosslinked with genipin and freeze-dried to serve in a flake/disc-like form. VAN-loaded carriers were characterized for their size, stability, and encapsulation efficiency (EE) using dynamic light scattering technique, zeta potential measurements, and UV-Vis spectroscopy, respectively. The synthesized composites were tested in terms of their physicochemical and biological features. Results: Spherical structures with sizes of about 200 nm and encapsulation efficiencies reaching values of approximately 60% were obtained. It was found that the resulting particles exhibit stability over time. The antibacterial activity of the developed materials against Staphylococcus aureus was established. Moreover, in vitro cell culture study revealed that the surfaces of all prepared systems are biocompatible as they supported the proliferation and adhesion of the model MG-63 cells. In addition, we have demonstrated significantly prolonged VAN release while minimizing the initial burst effect for the composites compared to bare nanoparticles and verified their desired physicochemical features during swellability, and degradation experiments. Conclusion: It is expected that the developed herein system will enable direct delivery of the antibiotic at an exposed to infections surgical site, providing drugs sustained release and thus will reduce the risk of systemic toxicity. This strategy would both inhibit biofilm formation and accelerate the healing process.

Efficacy of Intrawound Vancomycin in Prevention of Periprosthetic Joint Infection After Primary Total Knee Arthroplasty: A Prospective Double-Blinded Randomized Control Trial.

BACKGROUND: Periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is a devastating complication. Intrawound vancomycin powder has been shown to reduce infection rates in spine surgery, but its role in arthroplasty remains controversial. This prospective randomized control trial aimed to evaluate the efficacy of intrawound vancomycin in preventing PJI after primary TKA. METHODS: A total of 1,022 patients were randomized to the study group (n = 507, who received 2 grams intrawound vancomycin powder before arthrotomy closure) or to the control group (n = 515, no local vancomycin) with a minimum follow-up of 12-months. The primary outcome was the incidence of PJI or surgical site infection (SSI). Secondary outcomes included associated minor complications such as stitch abscess, persistent wound drainage, and delayed stitch removal. Other parameters evaluated include reoperation rates and incidences of nephrotoxicity. RESULTS: The overall infection rate in 1,022 patients was 0.66%. There was no significant difference in PJI rate in the study group (N = 1; 0.2%) versus the control group (N = 3; 0.58%), P = .264. Reoperation rates in the study group (N = 4; 0.78%) and control (N = 5; 0.97%), and SSI rates in the study (N = 1; 0.2%) and control groups (N = 2; 0.38%) were comparable. The Vancomycin cohort, however, demonstrated a significantly higher number of minor wound complications (n = 67; 13.2%) compared to the control group (n = 39; 7.56%, P < .05). Subgroup analysis showed diabetics in the study group to also have a higher incidence of minor wound complications (24 [14.1%] versus 10 [6.2%]; P < 05]. Multivariate analyses found that vancomycin use (odds ratio = 1.64) and smoking (odds ratio = 1.85) were associated with an increased risk of developing minor wound complications. No cases of nephrotoxicity were reported. CONCLUSIONS: Intrawound vancomycin powder does not appear to reduce PJI/SSI rate in primary total knee arthroplasties, including high-risk groups. Although safe from a renal perspective, intrawound vancomycin was associated with an increase in postoperative aseptic wound complications. Intrawound vancomycin may not be effective in reducing the rate of PJI in primary TKA.

Precision in Prevention: Tailoring Single-Use Negative Pressure Wound Therapy Utilization Through Artificial Intelligence-Based Surgical Site Complications Risk and Cost Modeling.

Background: Surgical site complications (SSCs) are common, yet preventable hospital-acquired conditions. Single-use negative pressure wound therapy (sNPWT) has been shown to be effective in reducing rates of these complications. In the era of value-based care, strategic allocation of sNPWT is needed to optimize both clinical and financial outcomes. Materials and Methods: We conducted a retrospective analysis using data from the Premier Healthcare Database (2017-2021) for 10 representative open procedures in orthopedic, abdominal, cardiovascular, cesarean delivery, and breast surgery. After separating data into training and validation sets, various machine learning algorithms were used to develop pre-operative SSC risk prediction models. Model performance was assessed using standard metrics and predictors of SSCs were identified through feature importance evaluation. Highest-performing models were used to simulate the cost-effectiveness of sNPWT at both the patient and population level. Results: The prediction models demonstrated good performance, with an average area under the curve of 76%. Prominent predictors across subspecialities included age, obesity, and the level of procedure urgency. Prediction models enabled a simulation analysis to assess the population-level cost-effectiveness of sNPWT, incorporating patient and surgery-specific factors, along with the established efficacy of sNPWT for each surgical procedure. The simulation models uncovered significant variability in sNPWT's cost-effectiveness across different procedural categories. Conclusions: This study demonstrates that machine learning models can effectively predict a patient's risk of SSC and guide strategic utilization of sNPWT. This data-driven approach allows for optimization of clinical and financial outcomes by strategically allocating sNPWT based on personalized risk assessments.

Cryopreserved bone flaps from decompressive craniectomies: a microbiological analysis.

PURPOSE: Surgical site infection (SSI) is a serious complication after cranioplasty. Due to the relatively frequent occurrence of post-cranioplasty SSI, the utility of autologous bone flap swab cultures surrounding cryopreservation as a reliable predictor has been the subject of an ongoing debate. This bicentric study aims to contribute to this topic by conducting an in-depth analysis of bone flaps obtained via decompressive craniectomies. This study had three major aims: assessments of 1) bacterial contamination of bone flaps after decompressive craniotomy, 2) impact of cryoconservation on contamination rates and 3) potential effectiveness of anti-infective treatment to reduce the germ load prior to cranioplasty. METHODS: Cryopreserved bone flaps from two centers were used. Microbiological cultivations of swabs prior to and after cryopreservation were taken and assessed for aerobic and anaerobic growth over a 14-day incubation period. Additionally, in a subset of bone flaps, swab testing was repeated after thorough rinsing with an anti-infectant (octenidine-phenoxyethanol) followed by saline. RESULTS: All 63 bone flaps (patients median age at surgery: 59 years) were obtained via decompressive craniectomies. Swabs done prior to cryopreservation revealed a 54% infection rate with Propionibacterium acnes being the most common microorganism in 65% of those cases. After thorough disinfection of the preserved bone flaps, all but one case showed no bacterial growth in swab testing. Furthermore, no relevant risk factors for bacterial contamination could be identified. CONCLUSION: This retrospective study showed the common presence of bacterial growth in cryopreserved bone flaps before and after freezing. Rinsing with octenidine-phenoxyethanol and saline effectively prevented bacterial growth in a notable percentage of cases, suggesting a potential strategy to reduce contamination. However, persistent bacterial growth in some cases underscores the need for further research to optimize antiseptic measures during autologous cranioplasty.

Pets, obesity and nurses: surgical site infections in the community.

Many surgical site infections (SSI) emerge after the patient is discharged from hospital. So, practice and district nurses should remain alert for SSIs and address modifiable risk factors, which include helping obese patients lose weight, optimising glucose control in people with diabetes and encouraging smoking cessation. Animals, including pets, are important reservoirs of resistant bacteria. By optimising SSI care, nurses can not only improve wound healing but also help preserve antibiotic efficacy.

Surgical Closure of Equine Abdomen, Prevention, and Management of Incisional Complications.

Although rarely fatal, complications of ventral midline laparotomy incision in equine patients increase hospitalization cost and duration and may jeopardize return to athletic function. Therefore, many techniques have been developed to reduce their occurrence and expedite their resolution when they occur. Our technique of celiotomy incision closure includes the use of tension sutures (vertical U mattress) of polyglactin 910 on the linea alba, which is then apposed by polyglactin 910 interrupted sutures or a simple continuous pattern suture with a stop midway before routine closure of the superficial layers. The celiotomy incision is protected by an elastic bandage during the immediate postoperative period. This technique has been associated with favorable results: 5.3% confirmed incisional infections after a single celiotomy and 26.7% after repeat celiotomy. The overall incisional complication (serous/sanguineous discharge, hematoma, infection, hernia formation, and complete wound breakdown) occurrence was 9.5% and 33.3% after single and repeat laparotomy, respectively. In cases considered more susceptible to infection (early relaparotomy or laparotomy incisions longer than 30 cm), negative pressure therapy was found easy to apply on closed incisions. No detrimental effects were observed. However, the potential prophylactic benefit of this therapy needs to be confirmed in a larger group. In infected laparotomy wounds requiring drainage, the use of negative pressure therapy seemed to have a positive effect on the formation of granulation tissue. However, there was no control group to allow statistical confirmation. Finally, one case of complete breakdown of the laparotomy incision was managed by stainless steel retention sutures, the application of negative pressure therapy, and a hernia belt. At re-evaluation 15 months post-surgery, several small hernias were detected, but the horse had returned to his previous level of sports performance and had not shown any episode of colic.

Accuracy of the Wound Healing Questionnaire in the diagnosis of surgical-site infection after abdominal surgery in low- and middle-income countries.

INTRODUCTION: Telemedicine is being adopted for postoperative surveillance but requires evaluation for efficacy. This study tested a telephone Wound Healing Questionnaire (WHQ) to diagnose surgical site infection (SSI) after abdominal surgery in low- and middle-income countries. METHOD: A multi-centre, international, prospective study was embedded in the FALCON trial; a factorial RCT testing measures to reduce SSI in seven low- and middle-income countries (NCT03700749). It was conducted according to a pre-registered protocol (SWAT126) and reported according to STARD guidelines. The reference test was in-person review by a trained clinician at 30 postoperative days according to US Centres for Disease Control criteria. The index test was telephone administration of an adapted WHQ at 27 to 30 postoperative days by a researcher blinded to the outcome of in-person review. The sum of item response scores generated an overall score between 0 and 29. The primary outcome was the diagnostic accuracy of the WHQ, defined as the proportion of SSI correctly identified by the telephone WHQ, and summarized using the area under the receiving operator characteristic curve (AUROC) and diagnostic test accuracy statistics. RESULTS: Patients were included from three upper-middle income (396 patients, 13 hospitals), three lower-middle income (746 patients, 19 hospitals), and one low-income country (54 patients, 4 hospitals). 90.3% (1088 of 1196) patients were successfully contacted. Those with non-midline incisions (adjusted odds ratio: 0.36, 95% c.i. 0.17 to 0.73, P=0.005) or a confirmed diagnosis of SSI on in-person assessment (odds ratio: 0.42, 95% c.i. 0.20 to 0.92, P=0.006) were harder to reach. The questionnaire correctly discriminated between most patients with and without SSI (AUROC 0.869, 95% c.i. 0.824 to 0.914), which was consistent across subgroups. A representative cut-off score of ≥4 displayed a sensitivity of 0.701 (0.610-0.792), specificity of 0.911 (0.878-0.943), positive predictive value of 0.723 (0.633-0.814) and negative predictive value of 0.901 (0.867-0.935). CONCLUSION: SSI can be diagnosed using a telephone questionnaire (obviating in-person assessment) in low resource settings.

A wound infection happens when germs enter the cut made in your body by a doctor when you are operated on. Germs are small organisms that cannot be seen by your eyes, but they can cause problems in the healing of the cut. Infection is the most common problem after surgery and can delay you getting out of hospital and back to normal life. The current way to check whether you have an infection is for a doctor or nurse to look at the cut made on your tummy and see how it is healing. For example, a doctor may check if the cut has a green liquid oozing from it or if the area of the wound is red or swollen. A month after you leave hospital, a doctor may ask you to come back for a follow-up visit. However, this will require you to travel to hospital and take a day off work or away from your family, and can be expensive and time-consuming if you travel far. We wanted to find out if talking to a doctor over the phone would work as well as you travelling to hospital to show the wound to a doctor or nurse in person. To do this, we asked over 1000 patients who had recently undergone surgery to be checked using both methods­to take a phone call from one doctor and be checked in person by a different doctor. We were able to compare the phone follow-up and in-person check to see if the doctors came to a different conclusion. We also looked at whether patients were able to receive a phone call at home and their experience of the process. For most patients, the phone call from a doctor was just as good at seeing if a patient had an infection as a face-to-face check-up by a doctor. However, the phone call was not perfect all the time, particularly for patients with very mild infections. Most patients were able to receive the phone call after a few tries and all patients were very happy with the process. As an international research team, we are now trying new ways to improve the phone call, including looking at the wound over video if possible. A phone call to check how your wound is healing can now be used as a substitute for a face-to-face check-up by a doctor. If you have any worries about your wound after the phone call you should still seek help from a doctor or nurse. We hope that the phone call will be more convenient for patients like you to avoid travelling back to hospital and taking time away from your work and family.

Implementation of perioperative blood glucose monitoring and insulin infusion protocol can decrease postoperative infection rate in diabetic patients undergoing elective craniotomy: An observational study.

BACKGROUND: Severe perioperative hyperglycemia (SH) is a proven risk factor for postoperative complications after craniotomy. To reduce this risk, it has been proposed to implement the standardized clinical protocol for scheduled perioperative blood glucose concentration (BGC) monitoring. This would be followed by intravenous (IV) insulin infusion to keep BGC below 180 mg/dl in the perioperative period. The aim of this prospective observational study was to assess the impact of this type of protocol on the postoperative infection rate in patients undergoing elective craniotomy. METHODS: A total of 42 patients were prospectively enrolled in the study. Protocol included scheduled BGC monitoring in the perioperative period and rapid-acting insulin IV infusion when intraoperative SH was detected. The diagnosis of infection (wound, pulmonary, blood stream, urinary tract infection or central nervous system infection) was established according to CDC criteria within the first postoperative week. A previously enrolled group of patients with sporadic BGC monitoring and subcutaneous insulin injections for SH management was used as a control group. RESULTS: An infectious complication (i.e., pneumonia) was diagnosed only in one patient (2 %) in the prospective group. In comparison with the control group, a decrease in the risk of postoperative infection was statistically significant with OR = 0.08 [0.009 - 0.72] (p = 0.02). Implementation of the perioperative BGC monitoring and the correction protocol prevented both severe hyperglycemia and hypoglycemia with BGC < 70 mg/dl. CONCLUSION: Scheduled BGC monitoring and the use of low-dose insulin infusion protocol can decrease the postoperative infection rate in patients undergoing elective craniotomy. Future studies are needed to prove the causality of the implementation of such a protocol with an improved outcome.

Antibiotic impregnated catheters and intrathecal antibiotics for CSF shunt infection prevention in children undergoing low-risk CSF shunt surgery.

BACKGROUND: Cerebrospinal fluid (CSF) shunts allow children with hydrocephalus to survive and avoid brain injury (J Neurosurg 107:345-57, 2007; Childs Nerv Syst 12:192-9, 1996). The Hydrocephalus Clinical Research Network implemented non-randomized quality improvement protocols that were shown to decrease infection rates compared to pre-operative prophylactic intravenous antibiotics alone (standard care): initially with intrathecal (IT) antibiotics between 2007-2009 (J Neurosurg Pediatr 8:22-9, 2011), followed by antibiotic impregnated catheters (AIC) in 2012-2013 (J Neurosurg Pediatr 17:391-6, 2016). No large scale studies have compared infection prevention between the techniques in children. Our objectives were to compare the risk of infection following the use of IT antibiotics, AIC, and standard care during low-risk CSF shunt surgery (i.e., initial CSF shunt placement and revisions) in children. METHODS: A retrospective observational cohort study at 6 tertiary care children's hospitals was conducted using Pediatric Health Information System + (PHIS +) data augmented with manual chart review. The study population included children ≤ 18 years who underwent initial shunt placement between 01/2007 and 12/2012. Infection and subsequent CSF shunt surgery data were collected through 12/2015. Propensity score adjustment for regression analysis was developed based on site, procedure type, and year; surgeon was treated as a random effect. RESULTS: A total of 1723 children underwent initial shunt placement between 2007-2012, with 1371 subsequent shunt revisions and 138 shunt infections. Propensity adjusted regression demonstrated no statistically significant difference in odds of shunt infection between IT antibiotics (OR 1.22, 95% CI 0.82-1.81, p = 0.3) and AICs (OR 0.91, 95% CI 0.56-1.49, p = 0.7) compared to standard care. CONCLUSION: In a large, observational multicenter cohort, IT antibiotics and AICs do not confer a statistically significant risk reduction compared to standard care for pediatric patients undergoing low-risk (i.e., initial or revision) shunt surgeries.