ORCID Profile
0000-0002-4460-9286
Current Organisation
The Chinese University of Hong Kong Faculty of Medicine
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Publisher: Wiley
Date: 09-03-2021
DOI: 10.1111/ANAE.15458
Abstract: Peri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS‐CoV‐2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre‐operative SARS‐CoV‐2 infection were compared with those without previous SARS‐CoV‐2 infection. The primary outcome measure was 30‐day postoperative mortality. Logistic regression models were used to calculate adjusted 30‐day mortality rates stratified by time from diagnosis of SARS‐CoV‐2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre‐operative SARS‐CoV‐2 diagnosis. Adjusted 30‐day mortality in patients without SARS‐CoV‐2 infection was 1.5% (95%CI 1.4–1.5). In patients with a pre‐operative SARS‐CoV‐2 diagnosis, mortality was increased in patients having surgery within 0–2 weeks, 3–4 weeks and 5–6 weeks of the diagnosis (odds ratio (95%CI) 4.1 (3.3–4.8), 3.9 (2.6–5.1) and 3.6 (2.0–5.2), respectively). Surgery performed ≥ 7 weeks after SARS‐CoV‐2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5 (0.9–2.1)). After a ≥ 7 week delay in undertaking surgery following SARS‐CoV‐2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2–8.7) vs. 2.4% (95%CI 1.4–3.4) vs. 1.3% (95%CI 0.6–2.0), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS‐CoV‐2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.
Publisher: SAGE Publications
Date: 16-01-2023
DOI: 10.1177/03635465221145015
Abstract: Doxycycline (Doxy) has been shown to facilitate tendon healing by reducing on-site matrix metalloproteinase (MMP) activity, but its effect on graft healing after anterior cruciate ligament reconstruction (ACLR) has not been investigated, and the therapeutic effect of Doxy in preventing ACLR-induced posttraumatic osteoarthritis (PTOA) is unclear. Doxy promotes graft healing and alleviates the progression of PTOA after ACLR. Controlled laboratory study. Sprague Dawley rats (n = 74 age, 12-13 weeks male) that underwent ACLR were ided into untreated control and Doxy treatment (50 mg/kg/d orally until sacrifice) groups. At 2 and 6 weeks after surgery, graft healing was assessed by biomechanical testing, histology, immunohistochemical staining, and micro–computed tomography (μCT). The progression of PTOA was evaluated at 6 weeks by histology, the Mankin score, and immunofluorescence staining of the tibial plateau, and osteophyte formation was evaluated by μCT. Hindlimb weight distribution was evaluated at 6 weeks, and gait patterns were evaluated at 2 and 6 weeks. Intra-articular MMP activity was evaluated at 6 weeks in vivo using an MMP-activatable near-infrared fluorescent probe. Graft healing was enhanced by Doxy treatment, and the ultimate failure load ( P = .002) and stiffness of the graft ( P = .007) were significantly higher in the Doxy group at week 2. Bone mineral density and bone volume/total volume for both the tibial and the femoral tunnels at week 6 in the Doxy group were significantly higher compared with in the control group ( P .05). The overall graft healing scores were significantly higher in the Doxy group. Doxy treatment enhanced graft integration, intratunnel graft integrity, and collagen birefringence more collagen types 1 and 10 and less MMP-13 were found at the graft-bone interface. At week 6, the Doxy group had a lower modified Mankin score ( P = .033) and showed fewer MMP 13–positive chondrocytes at the articular cartilage surface ( P = .002), indicating moderate joint cartilage damage. μCT revealed less osteophyte formation, and gait analysis revealed more symmetric weightbearing and gait patterns, after Doxy treatment at week 6 ( P .05). In vivo imaging with the near-infrared fluorescent probe identified significantly lower intra-articular MMP activity in the Doxy group at week 6 ( P = .016). The oral administration of Doxy was able to synchronously promote graft healing and attenuate PTOA in an ACLR rat model. Our results indicated that Doxy, a widely used drug, is potentially beneficial to patients after ACLR.
Publisher: Wiley
Date: 24-08-2021
DOI: 10.1111/ANAE.15563
Abstract: SARS‐CoV‐2 has been associated with an increased rate of venous thromboembolism in critically ill patients. Since surgical patients are already at higher risk of venous thromboembolism than general populations, this study aimed to determine if patients with peri‐operative or prior SARS‐CoV‐2 were at further increased risk of venous thromboembolism. We conducted a planned sub‐study and analysis from an international, multicentre, prospective cohort study of elective and emergency patients undergoing surgery during October 2020. Patients from all surgical specialties were included. The primary outcome measure was venous thromboembolism (pulmonary embolism or deep vein thrombosis) within 30 days of surgery. SARS‐CoV‐2 diagnosis was defined as peri‐operative (7 days before to 30 days after surgery) recent (1–6 weeks before surgery) previous (≥7 weeks before surgery) or none. Information on prophylaxis regimens or pre‐operative anti‐coagulation for baseline comorbidities was not available. Postoperative venous thromboembolism rate was 0.5% (666/123,591) in patients without SARS‐CoV‐2 2.2% (50/2317) in patients with peri‐operative SARS‐CoV‐2 1.6% (15/953) in patients with recent SARS‐CoV‐2 and 1.0% (11/1148) in patients with previous SARS‐CoV‐2. After adjustment for confounding factors, patients with peri‐operative (adjusted odds ratio 1.5 (95%CI 1.1–2.0)) and recent SARS‐CoV‐2 (1.9 (95%CI 1.2–3.3)) remained at higher risk of venous thromboembolism, with a borderline finding in previous SARS‐CoV‐2 (1.7 (95%CI 0.9–3.0)). Overall, venous thromboembolism was independently associated with 30‐day mortality (5.4 (95%CI 4.3–6.7)). In patients with SARS‐CoV‐2, mortality without venous thromboembolism was 7.4% (319/4342) and with venous thromboembolism was 40.8% (31/76). Patients undergoing surgery with peri‐operative or recent SARS‐CoV‐2 appear to be at increased risk of postoperative venous thromboembolism compared with patients with no history of SARS‐CoV‐2 infection. Optimal venous thromboembolism prophylaxis and treatment are unknown in this cohort of patients, and these data should be interpreted accordingly.
Publisher: Wiley
Date: 23-03-2022
Abstract: Control over soft‐to‐hard tissue interfaces is attracting intensive worldwide research efforts. Herein, a bioactive film‐guided soft–hard interface design (SHID) for multi‐tissue integrative regeneration is shown. Briefly, a soft bioactive film with good elasticity matchable to native ligament tissue, is incorporated with bone‐mimic components (calcium phosphate cement, CPC) to partially endow the soft‐film with hard‐tissue mimicking feature. The hybrid film is elegantly compounded with a clinical artificial ligament to act as a buffer zone to bridge the soft (ligament) and hard tissues (bone). Moreover, the bioactive film‐decorated ligament can be rolled into a 3D bio‐instructive implant with spatial‐controllable distribution of CPC bioactive motifs. CPC then promotes the recruitment and differentiation of endogenous cells in to the implant inside part, which enables a vascularized bone growth into the implant, and forms a structure mimicking the biological ligament–bone interface, thereby significantly improving osteointegration and biomechanical property. Thus, this special design provides an effective SHID‐guided implant‐bioactivation strategy unreached by the traditional manufacturing methods, enlightening a promising technology to develop an ideal SHID for translational use in the future.
Publisher: Oxford University Press (OUP)
Date: 24-03-2021
DOI: 10.1093/BJS/ZNAB101
Abstract: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18–49, 50–69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351 best case 196, worst case 816) or non-cancer surgery (733 best case 407, worst case 1664). Both exceeded the NNV in the general population (1840 best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.
Publisher: Elsevier BV
Date: 09-2022
DOI: 10.1016/J.JOCA.2022.04.003
Abstract: Osteoarthritis (OA) affects the entire joint, initially with a low degree of inflammation. Synovitis is correlated with the severity of OA clinical symptoms and cartilage degradation. The synovial lymphatic system (SLS) plays a prominent role in clearing macromolecules within the joint, including the pro-inflammatory cytokines in arthritic status. Scattered evidence shows that impaired SLS drainage function leads to the accumulation of inflammatory factors in the joint and aggravates the progression of OA, and the role of SLS function in OA is less studied. This review summarizes the current understanding of synovial lymphatic function in OA progression and potential regulatory pathways and aims to provide a framework of knowledge for the development of OA treatments targeting lymphatic structure and functions. SLS locates in the subintima layer of the synovium and consists of lymphatic capillaries and lymphatic collecting vessels. Vascular endothelial growth factor C (VEGF-C) is the most critical regulating factor of lymphatic endothelial cells (LECs) and SLS. Nitric oxide production-induced impairment of lymphatic muscle cells (LMCs) and contractile function may attribute to drainage dysfunction. Preclinical evidence suggests that promoting lymphatic drainage may help restore intra-articular homeostasis to attenuate the progression of OA. SLS is actively involved in the homeostatic maintenance of the joint. Understanding the drainage function of the SLS at different stages of OA development is essential for further design of therapies targeting the function of these vessels.
Location: Hong Kong
No related grants have been discovered for Michael Tim Yun Ong.