During the COVID-19 pandemic, video/phone consultations (VPC) were increasingly utilised as an alternative to face-to-face (F2F) consultations, to minimise nosocomial viral exposure. We previously demonstrated that VPCs were highly rated by both patients and clinicians. This study compared satisfaction between both clinic modalities in contemporaneously delivered outpatient surveys. We also assessed the feasibility and effects of converting F2F orthopaedic consultations to VPC. Surveys were posted to patients who attended VPCs and F2F consultations at a large tertiary centre from August to October 2020 inclusive, across 51 specialties. F2F and VPC patients ranked their overall satisfaction with their consultation on a 10-point numerical scale (10=highest satisfaction). Simultaneously, a pilot study was undertaken of outpatient fracture clinics to identify patients suitable for VPCs, with X-rays (if needed) taken and transferred from satellite sites to reduce tertiary centre footfall. For F2F consultations, 1419 of 4465 surveys (31.8%) were returned with similar rates for VPCs (1332 of 4572, 29.1%). While mean satisfaction ratings were high for both clinic modalities, they were significantly higher for F2F: 9.13 (95% CI 9.05-9.22) for F2F clinics, compared to 8.23 (95% CI 8.11-8.35) for VPCs (p<0.001, t-test). F2F patients were almost four times more likely to state a preference for future F2F appointments compared to VPCs, whereas patients who attended VPCs showed an equal preference for either option (p< 0.001, chi2 test). 53% of 111 fracture clinic patients sampled were identified as suitable for VPCs. 1 patient (1.7%) requested their VPC to be converted to F2F due to poor symptom control. Our study showed patients reported high satisfaction ratings for both F2F clinics and VPCs, with prior experience of VPCs affecting patients’ future preferences. Only 1.7% of F2F patients converted to VPCs declined their virtual appointment. Our results support future use of VPCs

Background. Post-traumatic immunosuppression (PTI) after surgery increases vulnerability to nosocomial infections, sepsis, and death. Knee arthroplasty offers a sterile clinical model to characterise PTI and explore its underlying mechanisms. Methods. This prospective non-randomised cohort study of primary total knee arthroplasty was approved by the Local Ethics Committee. Exclusion criteria included revision-arthroplasty, pre-existing infections, blood-transfusions, malignancy, and auto-immune disease. 48 recruited patients fell into two groups, the first received unwashed anti-coagulated autologous salvaged blood transfusions after surgery (ASBT cohort, n=25). The second received no salvaged blood transfusions (NSBT cohort, n=18). Venous blood was sampled pre-operatively and within 3–7 days post-operatively. Salvaged blood was sampled at one and six hours post-operatively. Biomarkers of immune status included: interleukins (IL) or cytokines (x15), chemokines (x3), Damage-Associated-Molecular-Patterns (DAMPS) (x5), anti-microbial proteins (x3), CD24, and Sialic-acid-binding-Immunoglobulin-type-Lectin-10 (Siglec-10). Results were expressed as fold-change over pre-operative values. Only significant changes are described. Results. Certain biomarkers associated with sterile trauma were common to all 43 patients, including supra-normal: IL-6, IL-1-Receptor-Antagonist, IL-8, Heat-Shock-Protein-70 (HSP70), Calprotectin, CD24 and Siglec-10. But, whereas in NSBT patients post-operative pro-inflammatory biomarkers were sub-normal consistent with PTI, they were supra-normal in ASBT patients implying its reversal. These PTI-biomarkers included: IL-1β, IL-2, IL-17A, Interferon-gamma (IFN-γ), Tumour-Necrosis-Factor-alpha (TNF-α), and Annexin-A2. Reversal of PTI by salvaged blood was further endorsed in ASBT by sub-normal levels of the anti-inflammatory biomarkers: IL-4, IL-5, IL-10, and IL-13. Salvaged blood analyses revealed sustained supra-normal levels of DAMPs, CD24 and Siglec-10; and increasingly elevated levels of cytokines and chemokines during the six hour collection period. Interestingly, plasma CD24, Siglec-10, HSP70 and Calprotectin levels were significantly correlated, implying physical association within the circulation. Conclusions. Several anti-inflammatory processes triggered by traumatised tissue induce systemic PTI, thereby increasing vulnerability to infections. Reversal of PTI by re-infusion of anti-coagulated salvaged blood suggests a novel source of immuno-stimulants

Summary. Coagulase-negative staphylococci, including S. epidermidis, have emerged as the leading pathogens of hospital-acquired biomaterial-related infections. These infections can be clinically indolent and challenging also for diagnostic imaging. In the current model of catheter-related infections, . 68. Ga-labeled Siglec-9 PET/CT imaging was able to detect peri-implant S. epidermidis bone infections. Introduction. Coagulase-negative staphylococci, including S. epidermidis, have emerged as the leading pathogen of nosocomial (hospital-acquired) biomaterial-related infections, including periprosthetic infections and intravascular catheter-related bloodstream infections. Pathogenic S. epidermidis strains exhibit robust attachment to implant surfaces and subsequent biofilm formation. By nature, the clinical picture of periprosthetic S. epidermidis infections can be indolent with vague signs of infection. These infections are also highly challenging for diagnostic imaging and microbiologic studies. Our recent experimental study of . 18. F-FDG-PET/CT confirmed that subacute peri-implant S. epidermidis infections, reflecting limited inflammatory reaction, are characterised by low . 18. F-FDG uptake. Vascular adhesion protein-1 (VAP-1) is an inflammation inducible endothelial protein, which controls leukocyte migration to sites of inflammation and infection. Siglec-9 is a leukocyte ligand of VAP-1. We hypothesised that . 68. Ga-labeled Siglec-9, developed for PET imaging of inflammation and cancer, could be a novel tracer also for early defection of S. epidermidis peri-implant bone infections. Material & Methods. Thirty adult male Sprague-Dawley rats were randomised into three groups (n=10/group). A clinical intravenous polymer catheter was introduced into the medullary cavity of the left tibia followed by injections of a clinical isolate of S. epidermidis (T-54580, 3 × 10. 8. CFU/mL) and an adjunct sodium morrhuate. In the positive control group, a clinical isolate of S. aureus (52/52A/80, 3 × 10. 5. CFU/mL) with sodium morrhuate was injected. In the negative control group, equal amount of sterile saline was injected via the catheter. The catheter, cut at the level of tibial tuberosity, was left in situ to serve as the implant. Two weeks after surgery, PET imaging with . 68. Ga-DOTA-Siglec-9 was performed with quantitative analysis of the standardised uptake value (SUV) in the region of interests both in vivo and ex vivo. SUV ratio between the operated and contralateral intact tibia was calculated. The presence of infections and the absence of contamination in the negative control group were verified by separate microbiological analyses of bone samples and retrieved implants. The presence of microbial biofilms on catheters was verified ex vivo with fluorescence microscope. Histologic inflammatory reaction was graded using a scoring system. Intergroup differences were tested by means of ANOVA with a post-hoc test. Results. Both staphylococcal strains caused histologically acute osteomyelitic changes. In . 68. Ga-DOTA-Siglec-9 PET/CT imaging of the negative control group, there was a significant difference (29.5%, p<0.001) in the SUV ratio of the operated and contralateral tibia, demonstrating aseptic inflammatory reaction to catheter implantation. The corresponding SUV ratio values were 58.1% in the S. epidermidis group and 41.7% in the S. aureus group. The uptake in the S. epidermidis group was significantly (p=0.009) higher than in the negative control group. Discussion/Conclusion. The animal model was reproducible in creation of culture-positive biomaterial-related infections. . 68. Ga-labeled Siglec-9 PET/CT imaging was able to demonstrate aseptic inflammation in the negative control group and the tracer also detected peri-implant bone infections caused by S. epidermidis