The Thresholds of Caprini Score Associated With Increased Risk of Venous Thromboembolism Across Different Specialties: A Systematic Review.

OBJECTIVE: Estimation of the specific thresholds of the Caprini risk score (CRS) that are associated with the increased incidence of venous thromboembolism (VTE) across different specialties, including identifying the highest level of risk. BACKGROUND: Accurate risk assessment remains an important but often challenging aspect of VTE prophylaxis. One well-established risk assessment model is CRS, which has been validated in thousands of patients from many different medical and surgical specialties. METHODS: A search of MEDLINE and the Cochrane Library was performed in March 2022. Manuscripts that reported on (1) patients admitted to medical or surgical departments and (2) had their VTE risk assessed by CRS and (3) reported on the correlation between the score and VTE incidence, were included in the analysis. RESULTS: A total of 4562 references were identified, and the full text of 202 papers was assessed for eligibility. The correlation between CRS and VTE incidence was reported in 68 studies that enrolled 4,207,895 patients. In all specialties, a significant increase in VTE incidence was observed in patients with a CRS of ≥5. In most specialties thresholds of ≥7, ≥9, and ≥11 to 12 were associated with dramatically increased incidences of VTE. In COVID-19, cancer, trauma, vascular, general, head and neck, and thoracic surgery patients with ≥9 and ≥11 to 12 scores the VTE incidence was extremely high (ranging from 13% to 47%). CONCLUSION: The Caprini score is being used increasingly to predict VTE in many medical and surgical specialties. In most cases, the VTE risk for individual patients increases dramatically at a threshold CRS of 7 to 11.

Utilization of the Caprini Score for Risk Stratification of the Arthroplasty Patient in the Prevention of Postoperative Venous Thrombosis.

Venous thromboembolism (VTE) is a serious and predictable complication following arthroplasty. It has been recognized that a strategy utilizing individualized anticoagulation choices based on patient risk stratification results in improved patient outcomes. A 2013 version of the Caprini Risk Score has previously been validated for use in total joint arthroplasty. A Caprini score of 10 or greater assesses the patient as "high risk" while 9 or less is considered "low risk." Patients scored as "low risk" for postoperative VTE receive enteric coated aspirin 81 mg twice a day for 6 weeks. Patients scored as "high risk" for VTE are prescribed apixaban. This retrospective cohort study was conducted to assess the safety and efficacy of the thromboprophylaxis treatment prescribed based on a standardized risk assessment protocol for the calendar year 2020. Patients having total hip arthroplasty, total knee arthroplasty, revision total hip arthroplasty, revision total knee arthroplasty, or bilateral arthroplasties by 13 surgeons (N = 873) were reviewed. Patients were risk assessed using the Caprini Risk Score and thromboprophylaxis was prescribed based on the score obtained. The annual rate of VTE was 0.2%. The Caprini Risk Score is an effective approach to individualize thromboprophylaxis choices after total joint arthroplasty.

The Effect of BMI and Gender on Bleeding Events when Rivaroxaban Is Administered for Thromboprophylaxis Following Total Hip and Total Knee Arthroplasty.

Rivaroxaban is approved in Europe and the United States for thromboprophylaxis following total joint arthroplasty. As the rate of obesity increases, confirming safety and efficacy in this patient population is paramount. This retrospective chart review assessed the efficacy and safety of rivaroxaban between two body mass index (BMI) groups: normal or overweight (< 30 kg/m2) and obese or morbidly obese (≥30 kg/m2). Safety outcome was a major bleeding event, defined as a decrease in hemoglobin of at least 2 g/dL from postoperative day 1(POD 1) to discharge or a blood transfusion of at least two units. Efficacy outcome was venous thromboembolism within 35 days postoperatively. There were 68 (68/1,241; 5.48%) major bleeding events. There was no significant association between major bleeding events and BMI in the univariable analysis (p < 0.36). However, after adjusting for other factors in the multivariable model, there was a significant interaction between BMI and gender (p < 0.001). Among males, the incidence of major bleeding events was three times greater in obese/morbidly obese subjects as compared with normal/overweight male subjects (odds ratio [OR]: 3.09, 95% confidence interval [CI]: 1.25, 7.62). Among females, incidence of having a major bleeding event was almost two times greater in normal/overweight subjects as compared with obese/morbidly obese female subjects (OR: 2.17, 95% CI: 1.10, 4.35). Incidence of venous thromboembolism was 0.4% in each group. The authors' study results highlight a previously unexplored association between BMI and gender-dependent differences in bleeding outcomes when rivaroxaban is used for thromboprophylaxis following total joint arthroplasty.

Resumption of Elective Orthopaedic Surgery in the US Epicenter of COVID-19: Overcoming the Continuous Challenges.

On 1 March 2020, New York State confirmed its first case of COVID-19. An explosive progression of hospitalizations ensued, and all elective surgeries were cancelled between 23 March and 13 May 2020 per federal and state mandate. Upon return to elective surgery in May, 2020, the hospital found itself navigating uncharted territory. The unpredictability of the post-pandemic environment has required the healthcare team to constantly reassess and revise processes to ensure optimal patient outcomes, as well as safe practices for staff providing perioperative care. Health care professionals must continue to remain adaptable and amenable to constant change.

Localization of DIR1 at the tissue, cellular and subcellular levels during Systemic Acquired Resistance in Arabidopsis using DIR1:GUS and DIR1:EGFP reporters.

BACKGROUND: Systemic Acquired Resistance (SAR) is an induced resistance response to pathogens, characterized by the translocation of a long-distance signal from induced leaves to distant tissues to prime them for increased resistance to future infection. DEFECTIVE in INDUCED RESISTANCE 1 (DIR1) has been hypothesized to chaperone a small signaling molecule to distant tissues during SAR in Arabidopsis. RESULTS: DIR1 promoter:DIR1-GUS/dir1-1 lines were constructed to examine DIR1 expression. DIR1 is expressed in seedlings, flowers and ubiquitously in untreated or mock-inoculated mature leaf cells, including phloem sieve elements and companion cells. Inoculation of leaves with SAR-inducing avirulent or virulent Pseudomonas syringae pv tomato (Pst) resulted in Type III Secretion System-dependent suppression of DIR1 expression in leaf cells. Transient expression of fluorescent fusion proteins in tobacco and intercellular washing fluid experiments indicated that DIR1's ER signal sequence targets it for secretion to the cell wall. However, DIR1 expressed without a signal sequence rescued the dir1-1 SAR defect, suggesting that a cytosolic pool of DIR1 is important for the SAR response. CONCLUSIONS: Although expression of DIR1 decreases during SAR induction, the protein localizes to all living cell types of the vasculature, including companion cells and sieve elements, and therefore DIR1 is well situated to participate in long-distance signaling during SAR.

Characterization of C3--C4 intermediate species in the genus Heliotropium L. (Boraginaceae): anatomy, ultrastructure and enzyme activity.

Photosynthetic pathway characteristics were studied in nine species of Heliotropium (sensu lato, including Euploca), using assessments of leaf anatomy and ultrastructure, activities of PEP carboxylase and C4 acid decarboxylases, and immunolocalization of ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco) and the P-subunit of glycine decarboxylase (GDC). Heliotropium europaeum, Heliotropium calcicola and Heliotropium tenellum are C3 plants, while Heliotropium texanum and Heliotropium polyphyllum are C4 species. Heliotropium procumbens and Heliotropium karwinskyi are functionally C3, but exhibit 'proto-Kranz' anatomy where bundle sheath (BS) cells are enlarged and mitochondria primarily occur along the centripetal (inner) wall of the BS cells; GDC is present throughout the leaf. Heliotropium convolvulaceum and Heliotropium greggii are C3--C4 intermediates, with Kranz-like enlargement of the BS cells, localization of mitochondria along the inner BS wall and a loss of GDC in the mesophyll (M) tissue. These C3--C4 species of Heliotropium probably shuttle photorespiratory glycine from the M to the BS tissue for decarboxylation. Heliotropium represents an important new model for studying C4 evolution. Where existing models such as Flaveria emphasize diversification of C3--C4 intermediates, Heliotropium has numerous C3 species expressing proto-Kranz traits that could represent a critical initial phase in the evolutionary origin of C4 photosynthesis.

Compound leaf development in the palm Chamaedorea elegans is KNOX-independent.

PREMISE OF THE STUDY: How a leaf acquires its shape is a major and largely unresolved question in plant biology. This problem is particularly complex in the case of compound leaves, where the leaf blade is subdivided into leaflets. In many eudicots with compound leaves, class I KNOTTED1-LIKE HOMEOBOX (KNOX) genes are upregulated in the leaf primordium and promote leaflet initiation, while KNOX genes are restricted to the shoot apical meristem in simple-leaved plants. In monocots, however, little is known about the extent of KNOX contribution to compound leaf development, and we aimed to address this issue in the palm Chamaedorea elegans. METHODS: We investigated the accumulation pattern of KNOX proteins in shoot apical meristems and leaf primordia of the palm C. elegans using immunolocalization experiments. KEY RESULTS: KNOX proteins accumulated in vegetative and inflorescence apical meristems and in the subtending stem tissue, but not in the plicated regions of the leaf primordia. These plicated areas form during primary morphogenesis and are the only meristematic tissue in the developing primordium. In addition, KNOX proteins did not accumulate in any region of the developing leaf during secondary morphogenesis, when leaflets separate to create the final pinnately compound leaf. CONCLUSIONS: The compound leaf character in palms, C. elegans in particular and likely other pinnately compound palms, does not depend on the activities of KNOX proteins.

Interaction Between Low-Dose Aspirin and Nonsteroidal Anti-Inflammatory Drugs Can Compromise Aspirin's Efficacy in Preventing Venous Thrombosis Following Total Joint Arthroplasty.

Total joint arthroplasty is a rapid recovery procedure with patients optimized quickly in preparation for discharge. Two significant postoperative goals are effective pain management and prevention of postoperative venous thromboembolism (VTE). Low-risk patients receive aspirin 81 mg twice daily for VTE prophylaxis; this dosing regimen has been reduced over the past few years from 325 mg to 162 mg to 81 mg twice daily. Unless contraindications exist, all patients receive multimodal pain management that includes the use of celecoxib or meloxicam. Upon reduction of the aspirin dose to 81 mg twice daily, we rapidly identified 2 patients who developed a pulmonary embolus when celecoxib or meloxicam was administered concurrently with aspirin. The interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and low-dose aspirin varies among the different NSAIDs. It is also highly dependent on numerous factors, including time of administration, dose of aspirin, and both pharmacodynamics and dose of the NSAID. Real-world outcomes of concomitant administration of NSAIDs with low-dose aspirin led to increased incidence of VTE, possibly due to competitive inhibition of aspirin at platelet receptor sites. This interaction was mitigated by altering the administration times of both agents.

Lessons Learned: Using the Caprini Risk Assessment Model to Provide Safe and Efficacious Thromboprophylaxis Following Hip and Knee Arthroplasty.

Two of the more common potential complications after arthroplasty are venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolus (PE), and excess bleeding. Appropriate chemoprophylaxis choices are essential to prevent some of these adverse events and from exacerbating others. Risk stratification to prescribe safe and effective medications in the prevention of postoperative VTE has shown benefit in this regard. The Department of Orthopaedic Surgery at Syosset Hospital/Northwell Health, which performs over 1200 arthroplasties annually, has validated and is using the 2013 version of the Caprini Risk Assessment Model (RAM) to stratify each patient for risk of postoperative VTE. This tool results in a culling of information, past and present, personal and familial, that provides a truly thorough evaluation of the patient's risk for postoperative VTE. The Caprini score then guides the medication choices for thromboprophylaxis. The Caprini score is only valuable if the data is properly collected, and we have learned numerous lessons after applying it for 18 months. Risk stratification requires practice and experience to achieve expertise in perioperative patient evaluation. Having access to pertinent patient information, while gaining proficiency in completing the Caprini RAM, is vital to its efficacy. Ongoing, real time analyses of patient outcomes, with subsequent change in process, is key to improving patient care.

Resumption of Elective Orthopaedic Surgery in the US Epicenter of COVID-19.

On March 1, 2020, New York State confirmed its first case of COVID-19. This state has had the largest initial mortality in the United States with more than 479,000 confirmed cases and over 25,000 deaths as of October 10, 2020. All elective surgeries in New York State were suspended on March 23, 2020, due to the national state of emergency. Syosset Hospital is a 75-bed community hospital dedicated primarily to elective surgery. During the COVID-19 surge, the hospital was converted to provide needed beds for the treatment of COVID-19 illness. In anticipation of the resumption of urgent elective procedures, this hospital became one of the two designated sites within the Northwell Health system to be "non-COVID." Once the hospital was emptied of all inpatients, a complete and thorough cleaning and disinfection was performed on the entire building. All equipment was thoroughly decontaminated following Centers for Disease Control and Prevention (CDC) guidelines. In anticipation of the resumption of elective surgery, each surgeon evaluated their cancelled case list to determine patient priority, based on a scale of 1 (elective, non-urgent), 2 (semi-urgent), 3 (urgent), to 4 (highly urgent). Site-specific disaster credentialing was expedited so that emergent surgeries could be performed by surgeons located at other Northwell sites. To ensure a structured and informative onboarding process, each visiting surgeon received a "welcome" email which requested pertinent information to facilitate the surgical process. Presurgical, surgical, and postoperative protocols were revised based on federal and local guidance and regulations. Resumption of elective surgery post COVID-19 placed the hospital into uncharted territory.

Shifts in leaf vein density through accelerated vein formation in C4 Flaveria (Asteraceae).

BACKGROUND AND AIMS: Leaf venation in many C(4) species is characterized by high vein density, essential in facilitating rapid intercellular diffusion of C(4) photosynthetic metabolites between different tissues (mesophyll, bundle sheath). Greater vein density has been hypothesized to be an early step in C(4) photosynthesis evolution. Development of C(4) vein patterning is thought to occur from either accelerated or prolonged procambium formation, relative to ground tissue development. METHODS: Cleared and sectioned tissues of phylogenetically basal C(3) Flaveria robusta and more derived C(4) Flaveria bidentis were compared for vein pattern in mature leaves and vein pattern formation in developing leaves. KEY RESULTS: In mature leaves, major vein density did not differ between C(3) and C(4) Flaveria species, whereas minor veins were denser in C(4) species than in C(3) species. The developmental study showed that both major and minor vein patterning in leaves of C(3) and C(4) species were initiated at comparable stages (based on leaf length). An additional vein order in the C(4) species was observed during initiation of the higher order minor veins compared with the C(3) species. In the two species, expansion of bundle sheath and mesophyll cells occurred after vein pattern was complete and xylem differentiation was continuous in minor veins. In addition, mesophyll cells ceased dividing sooner and enlarged less in C(4) species than in C(3) species. CONCLUSIONS: Leaf vein pattern characteristic to C(4) Flaveria was achieved primarily through accelerated and earlier offset of higher order vein formation, rather than other modifications in the timing of vein pattern formation, as compared with C(3) species. Earlier cessation of mesophyll cell division and reduced expansion also contributed to greater vein density in the C(4) species. The relatively late expansion of bundle sheath and mesophyll cells shows that vein patterning precedes ground tissue development in C(4) species.

Implementation and Validation of the 2013 Caprini Score for Risk Stratification of Arthroplasty Patients in the Prevention of Venous Thrombosis.

Appropriate chemoprophylaxis choice following arthroplasty requires accurate patient risk assessment. We compared the results of our prospective department protocol to the Caprini risk assessment model (RAM) retrospectively in this study group. Our goal was to determine whether the department protocol or the Caprini score would identify venous thromboembolism (VTE) events after total joint replacement. A secondary purpose was to validate the 2013 Caprini RAM in joint arthroplasty and determine whether patients with VTE would be accurately identified using the Caprini score. A total of 1078 patients met inclusion criteria. A Caprini score of 10 or greater is considered high risk and a score of 9 or less is considered low risk. The 2013 version of the Caprini RAM retrospectively stratified 7 of the 8 VTE events correctly, while only 1 VTE was identified with the prospective department protocol. This tool provided a consistent, accurate, and efficacious method for risk stratification and selection of chemoprophylaxis.

Completion of the Updated Caprini Risk Assessment Model (2013 Version).

The Caprini risk assessment model (RAM) has been validated in over 250 000 patients in more than 100 clinical trials worldwide. Ultimately, appropriate treatment options are dependent on precise completion of the Caprini RAM. As the numerical score increases, the clinical venous thromboembolism rate rises exponentially in every patient group where it has been properly tested. The 2013 Caprini RAM was completed by specially trained medical students via review of the presurgical assessment history, medical clearances, and medical consults. The Caprini RAM was completed for every participant both preoperatively and predischarge to ensure that any changes in the patient's postoperative course were captured by the tool. This process led to the development of completion guidelines to ensure consistency and accuracy of scoring. The 2013 Caprini scoring system provides a consistent, thorough, and efficacious method for risk stratification and selection of prophylaxis for the prevention of venous thrombosis.

Primary vascular pattern and expression of ATHB-8 in shoots of Arabidopsis.

• Primary vascular pattern determines pathways of long distance transport for water, nutrients and signalling molecules within plant shoot systems. • Expression of an Arabidopsis thaliana homeobox gene 8::GUS construct is restricted to the procambium and provides a molecular marker for vascular pattern at early developmental stages. • Primary vascular pattern and phyllotaxis are highly coordinated, with vascular sympodia corresponding to phyllotactic parastichies. During vegetative development, primary vasculature forms a reticulate pattern, with each leaf trace derived from two vascular sympodia. Shoot phase change is marked by alterations of this fundamental pattern. Formation of leaf trace procambial strands is temporally coordinated with primordium initiation, but ATHB-8::GUS expression is discontinuous in these strands at early stages. • The interconnection of vascular sympodia provides alternate pathways for long distance transport in shoots of A. thaliana and reflects the limited secondary growth in this species. ATHB-8::GUS expression identifies a prepattern that precedes anatomical definition of procambium. The longitudinal discontinuity in ATHB-8::GUS expression indicates that one function of this gene is to define the xylem components of vascular radial pattern.

Key innovations in the evolution of Kranz anatomy and C4 vein pattern in Flaveria (Asteraceae).

Kranz anatomy and C(4) vein pattern are required for C(4) biochemical functioning in C(4) plants; however, the evolutionary timing of anatomical and biochemical adaptations is unknown. From the genus Flaveria, 16 species (C(3), C(4), intermediates [C(3)-C(4), C(4)-like]) were analyzed, novel anatomical and vein pattern characters were analyzed and key anatomical differences among photosynthetic groups were highlighted. A stepwise acquisition of anatomical and vein pattern traits prior to derived biochemistry was outlined on the basis of the phylogeny of Flaveria. Increased vein density represents a potential "precondition" contributing to lower ratios of photosynthetic tissues (mesophyll, bundle sheath) and precedes further anatomical and biochemical modifications observed in derived C(3)-C(4) intermediates. In derived Flaveria species, bundle sheath volume is modified through cell expansion, whereas mesophyll volume is altered through mesophyll cell expansion, reductions in the number of ground tissue layers, and increased vein density. Results demonstrated that key anatomical features of C(4) plants are also required for C(3)-C(4) biochemical intermediacy, and anatomical and biochemical alterations acquired during evolution of intermediacy may predispose a species for evolution of C(4) photosynthesis. C(4)-like species are similar to C(4) species, demonstrating that Kranz anatomy is fully evolved before complete C(4) biochemistry is achieved.

Diversity of Kranz anatomy and biochemistry in C4 eudicots.

C(4) photosynthesis and Kranz anatomy occur in 16 eudicot families, a striking example of convergent evolution. Biochemical subtyping for 13 previously undiagnosed C(4) eudicot species indicated that 10 were NADP-malic enzyme (ME) and three were NAD-ME. A total of 33 C(4) species, encompassing four Kranz anatomical types (atriplicoid, kochioid, salsoloid, and suaedioid), and 21 closely related C(3) species were included in a quantitative anatomical study in which we found that, unlike similar studies in grasses and sedges, anatomical type had no predictive value for the biochemical subtype. In a multivariate canonical discriminant analysis, C(4) species were distinguished from C(3) species by the mesophyll to bundle sheath ratio and exposure of the bundle sheath surface to intercellular space. Discrimination between NADP-ME and NAD-ME was not significant, although in a Mantel test grouping by biochemical subtype was significant, while grouping by family was not. This comprehensive survey of C(4) anatomy and biochemistry unequivocally demonstrated that atriplicoid anatomy and NADP-ME biochemistry predominate in many evolutionary lineages. In addition to a main decarboxylating enzyme, high activity of a second decarboxylating enzyme was often observed. Notably, PEP-carboxykinase activity was significant in a number of species, demonstrating that this enzyme could also serve as a secondary pathway for C(4) metabolism in eudicots.

Modification of cell proliferation patterns alters leaf vein architecture in Arabidopsis thaliana.

Formation of leaf vascular pattern requires regulation of a number of cellular processes, including cell proliferation. To assess the role of cell proliferation during vein order formation, leaf development in genetic lines exhibiting aberrant cell proliferation patterns due to altered expression patterns of ANT and ICK1 genes was analyzed. Modification of cell proliferation patterns alters the number of higher order veins and the number of minor tertiary veins remodeled as intersecondary veins in Arabidopsis rosette leaves. Minor vein complexity, as indicated by branch point and freely ending veinlet number, is highly correlated with a decrease or increase in cell proliferation. Observations of procambial strand formation in modified cell proliferation pattern lines showed that vein pattern is specified early in leaf development and that formation of freely ending veinlets is temporally correlated with the expansion of ground meristem when cell proliferation is terminated prematurely. Taken together, our observations indicate that: (1) genes that modulate cell proliferation play a key role in regulating the meristematic competence of ground meristem cells to form procambium and vein pattern during leaf development, and (2) ANT is a crucial part of this regulation.

Cell wall degradation and modification during programmed cell death in lace plant, Aponogeton madagascariensis (Aponogetonaceae).

An unusual form of leaf morphogenesis occurs in the aquatic, lace plant, Aponogeton madagascariensis (Aponogetonaceae). Early in development, discrete patches of cells undergo programmed cell death (PCD) and form perforations during leaf expansion. In addition to the protoplasts, walls of the dying cells are degraded during PCD. The cuticle of the perforation site is eroded first, followed by dissolution of cell wall matrix components, so that walls appear as loose fibrillar networks as perforations form. Gel diffusion assays of wall-degrading enzyme activity indicated that pectinases are active throughout leaf development, while cellulase activity was restricted to early stages of perforation formation. Alcian blue staining showed that degrading walls remain rich in pectin, and immunolocalization of pectin epitopes indicated that the proportions of esterified and de-esterifed pectins do not change significantly. Walls of perforation border cells are modified by suberin deposition late in development, and reactive oxygen species, thought to have a role in polymerization of phenolic suberin monomers, are present at the same stage. This timing suggests that suberization may limit the spread of PCD and provide an apoplastic barrier against microbial invasion but does not initiate PCD.