An Efficient Vein Pattern-based Recognition System

This paper presents an efficient human recognition system based on vein pattern from the palma dorsa. A new absorption based technique has been proposed to collect good quality images with the help of a low cost camera and light source. The system automatically detects the region of interest from the image and does the necessary preprocessing to extract features. A Euclidean Distance based matching technique has been used for making the decision. It has been tested on a data set of 1750 image samples collected from 341 individuals. The accuracy of the verification system is found to be 99.26% with false rejection rate (FRR) of 0.03%.Comment: IEEE Publication format, International Journal of Computer Science and Information Security, IJCSIS, Vol. 8 No. 1, April 2010, USA. ISSN 1947 5500, http://sites.google.com/site/ijcsis

Trans-osseous intraoperative limb length measurement in hip replacement surgery

Background: Discrepancy of the limb length following total hip replacement is one of common complication. To reduce the occurrence, various modalities are used like pre-operative templating, navigation assisted measurements and intraoperative methods. This study was done using trans-osseous method of measurement using hip gauge which provides a faster, simpler assessment of limb length.Methods: A prospective study of 25 patients who underwent uncemented hip arthroplasty was taken in the study and the LLD was measured before and after the surgical procedure. Patient were re-assessed for limb length discrepancy after 6 months with functional Harris hip score and radiological analysis on weight bearing standard X-ray antero-posterior view of the pelvis with bilateral hip joint.Results: The results showed significant improvement in limb length discrepancy, and analysis of postoperative radiographs found the mean length difference of 2.44 mm and average Harris hip score was 95.5. No device related complications were reported, and none of them complained of the discomfort related to limb-length discrepancy after surgery. Conclusions: Trans-osseous fixed method using hip gauge provides a faster, reproducible and simpler method for the assessment of Limb length and aids with offset placement, acetabular anteversion for precise cup placement. This is a reliable method as it can be used both in the primary and revision hip surgery and most importantly doesn’t require any additional intraoperative imaging

Comparing five equations to calculate estimated glomerular filtration rate to predict acute kidney injury following total joint arthroplasty.

BACKGROUND: Acute kidney injury (AKI) following total joint arthroplasty (TJA) is associated with increased morbidity and mortality. Estimated glomerular filtration rate (eGFR) is used as an indicator of renal function. The purpose of this study was (1) to assess each of the five equations that are used in calculating eGFR, and (2) to evaluate which equation may best predict AKI in patients following TJA. METHODS: The National Surgical Quality Improvement Program (NSQIP) was queried for all 497,261 cases of TJA performed from 2012 to 2019 with complete data. The Modification of Diet in Renal Disease (MDRD) II, re-expressed MDRD II, Cockcroft-Gault, Mayo quadratic, and Chronic Kidney Disease Epidemiology Collaboration equations were used to calculate preoperative eGFR. Two cohorts were created based on the development of postoperative AKI and were compared based on demographic and preoperative factors. Multivariate regression analysis was used to assess for independent associations between preoperative eGFR and postoperative renal failure for each equation. The Akaike information criterion (AIC) was used to evaluate predictive ability of the five equations. RESULTS: Seven hundred seventy-seven (0.16%) patients experienced AKI after TJA. The Cockcroft-Gault equation yielded the highest mean eGFR (98.6 ± 32.7), while the Re-expressed MDRD II equation yielded the lowest mean eGFR (75.1 ± 28.8). Multivariate regression analysis demonstrated that a decrease in preoperative eGFR was independently associated with an increased risk of developing postoperative AKI in all five equations. The AIC was the lowest in the Mayo equation. CONCLUSIONS: Preoperative decrease in eGFR was independently associated with increased risk of postoperative AKI in all five equations. The Mayo equation was most predictive of the development of postoperative AKI following TJA. The mayo equation best identified patients with the highest risk of postoperative AKI, which may help providers make decisions on perioperative management in these patients

Blood Transfusions in Revision Surgery for Prosthetic Hip and Knee Infection

Background: Surgery for prosthetic joint infection (PJI) can often have significant blood loss necessitating allogeneic blood transfusion (ABT). ABT is associated with higher rates of morbidity and death in revision TJA, particularly in the treatment of PJI. It is important to understand how the rates of ABT differ among the various surgical treatments of PJI. We compared ABT rates by procedure type among patients treated for PJI a multimodal blood conservation protocol. Methods: We retrospectively reviewed 143 operative cases of revision arthroplasty for hip and knee PJI involving 102 patients at a single institution between 2016 and 2018. Procedures were categorized as 1. irrigation and debridement (I&D) with modular component exchange (“modular component exchange”), 2. explantation with I&D and placement of antibiotic spacer (“explantation”), 3. I&D with antibiotic spacer exchange (“spacer exchange”), or 4. antibiotic spacer removal and prosthetic reimplantation (“reimplantation”). ABT rates and number of units transfused were assessed for the four procedures. Factors associated with ABT were assessed with a multilevel mixed-effects regression model. Results: Seventy-seven cases (54%) received ABT. The highest rates of ABT occurred during explantations (74%) and spacer exchanges (72%), followed by reimplantations (36%) and modular component exchanges (33%). After adjusting for perioperative variables, lower preoperative hemoglobin level was associated with higher odds of ABT (odds ratio [OR], 1.9 [per 1-g/dL decrease]; 95% confidence interval [CI]: 1.5–2.5). Explantation (OR, 14; 95% CI: 4.0–50), reimplantation (OR, 4.3; 95% CI: 1.1–16), and spacer exchanges (OR, 5.6; 95% CI: 1.1–28) were associated with greater odds of ABT. Antibiotic spacer exchanges (OR, 26; 95% CI: 2.1-315) and explantations (OR, 11; 95% CI: 2.1-61) were associated with greater odds of multiple unit transfusions. Discussion: Despite a restrictive transfusion protocol, ABT rates remain high in the surgical treatment of PJI. Antibiotic spacer exchange and explantation procedures had high rates of multiple unit transfusions, and additional units of blood should be made available. Preoperative anemia should be treated when possible, and further refinement of blood management protocols in prosthetic joint infection is necessary

Reducing unnecessary crossmatching for hip fracture patients by accounting for preoperative hemoglobin concentration

BACKGROUND: Maximum surgical blood order schedules were designed to eliminate unnecessary preoperative crossmatching prior to surgery in order to conserve blood bank resources. Most protocols recommend type and cross of 2 red blood cell (RBC) units for patients undergoing surgery for treatment of hip fracture. Preoperative hemoglobin has been identified as the strongest predictor of inpatient transfusion, but current maximum surgical blood order schedules do not consider preoperative hemoglobin values to determine the number of RBC units to prepare prior to surgery. AIM: To determine the preoperative hemoglobin level resulting in the optimal 2:1 crossmatch-to-transfusion (C:T) ratio in hip fracture surgery patients. METHODS: In 2015 a patient blood management (PBM) program was implemented at our institution mandating a single unit-per-occurrence transfusion policy and a restrictive transfusion threshold of \u3c 7 g/dL hemoglobin in asymptomatic patients and \u3c 8 g/dL in those with refractory symptomatic anemia or history of coronary artery disease. We identified all hip fracture patients between 2013 and 2017 and compared the preoperative hemoglobin which would predict a 2:1 C:T ratio in the pre PBM and post PBM cohorts. Prediction profiling and sensitivity analysis were performed with statistical significance set at P \u3c 0.05. RESULTS: Four hundred and ninety-eight patients who underwent hip fracture surgery between 2013 and 2017 were identified, 291 in the post PBM cohort. Transfusion requirements in the post PBM cohort were lower (51% vs 33%, P \u3c 0.0001) than in the pre PBM cohort. The mean RBC units transfused per patient was 1.15 in the pre PBM cohort, compared to 0.66 in the post PBM cohort (P \u3c 0.001). The 2:1 C:T ratio (inpatient transfusion probability of 50%) was predicted by a preoperative hemoglobin of 12.3 g/dL [area under the curve (AUC) 0.78 (95% confidence interval (CI), 0.72-0.83), Sensitivity 0.66] in the pre PBM cohort and 10.7 g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.88] in the post PBM cohort. A 50% probability of requiring \u3e 1 RBC unit was predicted by 11.2g/dL [AUC 0.80 (95%CI, 0.74-0.85), Sensitivity 0.87] in the pre PBM cohort and 8.7g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.84] in the post-PBM cohort. CONCLUSION: The hip fracture maximum surgical blood order schedule should consider preoperative hemoglobin in determining the number of units to type and cross prior to surgery

Predictors of Hospice Discharge Following Surgical Fixation of Hip Fracture

Introduction: Each year, over 300,000 people over the age of 65 are hospitalized for hip fractures, and even with co-management of patients perioperatively with a geriatric team, hip fractures in the elderly are associated with significant morbidity and mortality. Given the extreme morbidity and mortality faced by elderly patients in the post-injury period, recommendations have been put forth for the integration of palliative and even hospice care, to help improve patients’ quality of life. Our objectives were to 1) determine the proportion of patients discharged to hospice following hip fracture surgery and their 30-day mortality rates of these patients, and 2) identify the independent predictors of discharge to hospice. Methods: We retrospectively queried the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) for all hip fractures surgeries between the years of 2016 and 2018. Included cases were stratified into two cohorts: cases involving a discharge to hospice and non-hospice discharge. Variables assessed included patient demographics, comorbidities, perioperative characteristics, and postoperative outcomes. Differences between hospice and non-hospice patients were compared using chi-squared analysis or Fisher\u27s exact test for categorical variables and Student’s t-tests for continuous variables. A binary logistic regression model was used to assess independent predictors of hospice discharge with 30-day mortality. Results: Overall, 31,531 operatively treated hip fractures were identified, of which 281 (0.9%) involved a discharge to hospice. Patients discharged to hospice had a 67% 30-day mortality rate in comparison to 5.6% of patients not discharged to hospice (p \u3c 0.001). Disseminated cancer, dependent functional status, \u3e10% weight loss over six months preoperatively, and preoperative cognitive deficit were the strongest predictors of hospice discharge with 30-day mortality following hip fracture surgery. Conclusions: Current hospice utilization in hip fracture patients remains low, but 30-day mortality in these patients is high. An awareness of the associations between patient characteristics and discharge to hospice with 30-day mortality is important for surgeons to consider when discussing postoperative expectations and outcomes with these patients

Safety and efficacy of malaria vaccine candidate R21/Matrix-M in African children: a multicentre, double-blind, randomised, phase 3 trial

Background Recently, we found that a new malaria vaccine, R21/Matrix-M, had over 75% efficacy against clinical malaria with seasonal administration in a phase 2b trial in Burkina Faso. Here, we report on safety and efficacy of the vaccine in a phase 3 trial enrolling over 4800 children across four countries followed for up to 18 months at seasonal sites and 12 months at standard sites. Methods We did a double-blind, randomised, phase 3 trial of the R21/Matrix-M malaria vaccine across five sites in four African countries with differing malaria transmission intensities and seasonality. Children (aged 5–36 months) were enrolled and randomly assigned (2:1) to receive 5 μg R21 plus 50 μg Matrix-M or a control vaccine (licensed rabies vaccine [Abhayrab]). Participants, their families, investigators, laboratory teams, and the local study team were masked to treatment. Vaccines were administered as three doses, 4 weeks apart, with a booster administered 12 months after the third dose. Half of the children were recruited at two sites with seasonal malaria transmission and the remainder at standard sites with perennial malaria transmission using age-based immunisation. The primary objective was protective efficacy of R21/Matrix-M from 14 days after third vaccination to 12 months after completion of the primary series at seasonal and standard sites separately as co-primary endpoints. Vaccine efficacy against multiple malaria episodes and severe malaria, as well as safety and immunogenicity, were also assessed. This trial is registered on ClinicalTrials.gov, NCT04704830, and is ongoing. Findings From April 26, 2021, to Jan 12, 2022, 5477 children consented to be screened, of whom 1705 were randomly assigned to control vaccine and 3434 to R21/Matrix-M; 4878 participants received the first dose of vaccine. 3103 participants in the R21/Matrix-M group and 1541 participants in the control group were included in the modified per-protocol analysis (2412 [51·9%] male and 2232 [48·1%] female). R21/Matrix-M vaccine was well tolerated, with injection site pain (301 [18·6%] of 1615 participants) and fever (754 [46·7%] of 1615 participants) as the most frequent adverse events. Number of adverse events of special interest and serious adverse events did not significantly differ between the vaccine groups. There were no treatment-related deaths. 12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites for time to first clinical malaria episode. Similarly, vaccine efficacy against multiple clinical malaria episodes was 75% (71–78; p<0·0001) at the seasonal sites and 67% (59–73; p<0·0001) at standard sites. A modest reduction in vaccine efficacy was observed over the first 12 months of follow-up, of similar size at seasonal and standard sites. A rate reduction of 868 (95% CI 762–974) cases per 1000 children-years at seasonal sites and 296 (231–362) at standard sites occurred over 12 months. Vaccine-induced antibodies against the conserved central Asn-Ala-Asn-Pro (NANP) repeat sequence of circumsporozoite protein correlated with vaccine efficacy. Higher NANP-specific antibody titres were observed in the 5–17 month age group compared with 18–36 month age group, and the younger age group had the highest 12-month vaccine efficacy on time to first clinical malaria episode at seasonal (79% [95% CI 73–84]; p<0·001) and standard (75% [65–83]; p<0·001) sites. Interpretation R21/Matrix-M was well tolerated and offered high efficacy against clinical malaria in African children. This low-cost, high-efficacy vaccine is already licensed by several African countries, and recently received a WHO policy recommendation and prequalification, offering large-scale supply to help reduce the great burden of malaria in sub-Saharan Africa. Funding The Serum Institute of India, the Wellcome Trust, the UK National Institute for Health Research Oxford Biomedical Research Centre, and Open Philanthropy

Outpatient Simultaneous Bilateral Total Knee Arthroplasty: Is It Safe?

BACKGROUND: It is currently unknown if simultaneous bilateral total knee arthroplasty (si-BTKA) can also be safely performed in the outpatient setting. The primary aim of this study was to compare 30-day postoperative complication rates between outpatient and inpatient si-BTKA. METHODS: Adults undergoing simultaneous bilateral total knee arthroplasty (si-BTKA) from 2015-2019 were queried using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Our primary analysis compared the rates of complications between outpatient si-BTKA and inpatient si-BTKA using bivariate comparisons and multivariable logistic regression of outpatient and inpatient cases controlling for differences in baseline demographics and comorbidities. RESULTS: From 2015 to 2019, the utilization of outpatient si-BTKA increased from 0.6% to 10.5%. Outpatient si-BTKA were found to have significantly lower odds of any complication (OR = 0.49), minor complication (OR = 0.50), and postoperative transfusion (OR = 0.66) compared to inpatient cases. Outpatient si-BTKA also had a significantly shorter operative time. CONCLUSION: Compared to inpatient si-BTKA, patients who undergo outpatient si-BTKA do not demonstrate increased rates of any complication, severe complications, and minor complications within 30-days postoperatively. Further insight is needed on the effect of outpatient si-BTKA on long-term outcomes

Predictors of Hospice Discharge After Surgical Fixation of Hip Fractures.

BACKGROUND: Each year, over 300,000 people older than 65 years are hospitalized for hip fractures. Given the notable morbidity and mortality faced by elderly patients in the postinjury period, recommendations have been put forth for integrating palliative and, when needed, hospice care to improve patients\u27 quality of life. Our objective was to (1) understand the proportion of patients discharged to hospice after hip fracture surgery and their 30-day mortality rates and (2) identify the independent predictors of discharge to hospice. METHODS: We retrospectively queried the American College of Surgeons National Surgical Quality Improvement Program for all hip fracture surgeries between the years of 2016 and 2018. Included cases were stratified into two cohorts: cases involving a discharge to hospice and nonhospice discharge. Variables assessed included patient demographics, comorbidities, perioperative characteristics, and postoperative outcomes. Differences between hospice and nonhospice patients were compared using chi-squared analysis or the Fisher exact test for categorical variables and Student t -tests for continuous variables. A binary logistic regression model was used to assess independent predictors of hospice discharge with 30-day mortality. RESULTS: Overall, 31,531 surgically treated hip fractures were identified, of which only 281 (0.9%) involved a discharge to hospice. Patients discharged to hospice had a 67% 30-day mortality rate in comparison with 5.6% of patients not discharged to hospice ( P \u3c 0.001). Disseminated cancer, dependent functional status, \u3e10% weight loss over 6 months preoperatively, and preoperative cognitive deficit were the strongest predictors of hospice discharge with 30-day mortality after hip fracture surgery. CONCLUSIONS: Current hospice utilization in hip fracture patients remains low, but 30-day mortality in these patients is high. An awareness of the associations between patient characteristics and discharge to hospice with 30-day mortality is important for surgeons to consider when discussing postoperative expectations and outcomes with these patients. LEVEL OF EVIDENCE: Level III, retrospective comparative study