YEARS Algorithm Versus Wells' Score: Predictive Accuracies in Pulmonary Embolism Based on the Gold Standard CT Pulmonary Angiography.

OBJECTIVES: This study retrospectively applied Wells' score and YEARS algorithm to the same sample of patients to evaluate the predictive performance of each when compared with the gold standard CT pulmonary angiography. DESIGN: Retrospective analytical study. SETTING: A tertiary University Hospital in Ireland. PATIENTS: Data from 794 patients who underwent CT pulmonary angiography to rule out pulmonary embolism. INTERVENTIONS: Patients were analyzed using retrospective application of both Wells' score and YEARS algorithm. Sensitivity, specificity, and diagnostic odds ratio were calculated and compared. MEASUREMENTS AND MAIN RESULTS: Of 794 scans, 78 (9.8%) were positive for pulmonary embolism. The YEARS algorithm was more sensitive than the Wells' score (97.44% vs 74.36%) but was less specific (13.97% vs 33.94%). Furthermore, the diagnostic odds ratio of YEARS was higher than Wells' score (6.27 vs 1.48). YEARS provides better negative predictive value (98% vs 92.4%), and both scores have poor positive predictive value (10.9%). CONCLUSIONS: Both scores successfully exclude pulmonary embolism, although YEARS has a better negative predictive value. Both exhibit poor positive predictive value.

The pericyte microenvironment during vascular development.

Vascular pericytes provide critical contributions to the formation and integrity of the blood vessel wall within the microcirculation. Pericytes maintain vascular stability and homeostasis by promoting endothelial cell junctions and depositing extracellular matrix (ECM) components within the vascular basement membrane, among other vital functions. As their importance in sustaining microvessel health within various tissues and organs continues to emerge, so does their role in a number of pathological conditions including cancer, diabetic retinopathy, and neurological disorders. Here, we review vascular pericyte contributions to the development and remodeling of the microcirculation, with a focus on the local microenvironment during these processes. We discuss observations of their earliest involvement in vascular development and essential cues for their recruitment to the remodeling endothelium. Pericyte involvement in the angiogenic sprouting context is also considered with specific attention to crosstalk with endothelial cells such as through signaling regulation and ECM deposition. We also address specific aspects of the collective cell migration and dynamic interactions between pericytes and endothelial cells during angiogenic sprouting. Lastly, we discuss pericyte contributions to mechanisms underlying the transition from active vessel remodeling to the maturation and quiescence phase of vascular development.

Articular cartilage regeneration with autologous peripheral blood progenitor cells and hyaluronic acid after arthroscopic subchondral drilling: a report of 5 cases with histology.

PURPOSE: The purpose of this study was to evaluate the quality of articular cartilage regeneration after arthroscopic subchondral drilling followed by postoperative intraarticular injections of autologous peripheral blood progenitor cells (PBPCs) in combination with hyaluronic acid (HA). METHODS: Five patients underwent second-look arthroscopy with chondral core biopsy. These 5 patients are part of a larger pilot study in which 180 patients with International Cartilage Repair Society grade III and IV lesions of the knee joint underwent arthroscopic subchondral drilling followed by postoperative intra-articular injections. Continuous passive motion was used on the operated knee 2 hours per day for 4 weeks. Partial weight bearing was observed for the first 6 to 8 weeks. Autologous PBPCs were harvested 1 week after surgery. One week after surgery, 8 mL of the harvested PBPCs in combination with 2 mL of HA was injected intra-articularly into the operated knee. The remaining PBPCs were divided into vials and cryopreserved. A total of 5 weekly intra-articular injections were given. RESULTS: Second-look arthroscopy confirmed articular cartilage regeneration, and histologic sections showed features of hyaline cartilage. Apart from the minimal discomfort of PBPC harvesting and localized pain associated with the intra-articular injections, there were no other notable adverse reactions. CONCLUSIONS: Articular hyaline cartilage regeneration is possible with arthroscopic subchondral drilling followed by postoperative intraarticular injections of autologous PBPCs in combination with HA. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Comparison of anatomic versus nonanatomic placement of femoral tunnels in Achilles double-bundle posterior cruciate ligament reconstruction.

PURPOSE: In this study, we compared femoral tunnel pairs that differ by group in a double-bundle Achilles tendon allograft posterior cruciate ligament (PCL) reconstruction. METHODS: Group 1 patients had femoral tunnels drilled nearly within the footprint area most proximal and most distal to the axis of the femur. Group 2 patients had femoral tunnels drilled eccentrically within the footprint along an axis nearly perpendicular to the axis of the femur. Patient assessments were made subjectively with preoperative and postoperative assessments of Lysholm rating scale, posterior drawer test, and dial test. Objective assessments used range of motion and quadriceps circumference. Group 1 contained 7 patients with a mean age of 32 years (range, 20 to 46 years). Group 2 contained 10 patients with a mean age of 32 years (range, 20 to 46 years). RESULTS: Group 2 patients had significantly less posterior laxity than group 1 patients. Postoperatively, 6 patients in group 1 (86%) had a positive posterior drawer test compared with 3 in group 2 (30%). Rotational laxity was identified by dial test results postoperatively in 3 patients in group 1 (43%) compared with 0% in group 2. Extension deficit occurred in 2 patients in group 1 (29%) and 1 patient in group 2 (10%). Flexion deficit occurred more than twice as frequently in group 1 (71% [5 patients]) than in group 2 (30% [3 patients]). There were no statistically significant differences for other comparisons. CONCLUSIONS: The clinical outcomes support the group 2 method with femoral tunnel placement at the anterior-most and posterior-most portions of the femoral PCL insertion. The group 2 procedure described in this study incorporates advanced principles for successful outcomes with Achilles double-bundle PCL reconstruction. LEVEL OF EVIDENCE: Level III, case-control study.

Allograft tissue in ACL reconstruction.

Musculoskeletal allografts are an essential component for the surgical management of orthopedic injuries. Allografts are most frequently used in the knee for anterior cruciate ligament (ACL) deficiency and less frequently for other ligament lesions, meniscal transplant, and osteochondral repair. Clinical ACL outcomes have continued to improve as techniques and instrumentation have developed. Allografts are routinely used for ACL reconstructions and although some may argue against them, others feel that not using allografts is a disservice to their patients. The increase in demand for a larger and safer supply of allografts is directly related to the growth in the number of allografts being used. Allografts are safe, reliable, and when all factors are considered, is an excellent ligament replacement solution surgeons should consider for their ACL patients.

Costs and consequences of large-scale vector control for malaria.

BACKGROUND: Five large insecticide-treated net (ITN) programmes and two indoor residual spraying (IRS) programmes were compared using a standardized costing methodology. METHODS: Costs were measured locally or derived from existing studies and focused on the provider perspective, but included the direct costs of net purchases by users, and are reported in 2005 USD. Effectiveness was estimated by combining programme outputs with standard impact indicators. FINDINGS: Conventional ITNs: The cost per treated net-year of protection ranged from USD 1.21 in Eritrea to USD 6.05 in Senegal. The cost per child death averted ranged from USD 438 to USD 2,199 when targeting to children was successful.Long-lasting insecticidal nets (LLIN) of five years duration: The cost per treated-net year of protection ranged from USD 1.38 in Eritrea to USD 1.90 in Togo. The cost per child death averted ranged from USD 502 to USD 692.IRS: The costs per person-year of protection for all ages were USD 3.27 in KwaZulu Natal and USD 3.90 in Mozambique. If only children under five years of age were included in the denominator the cost per person-year of protection was higher: USD 23.96 and USD 21.63. As a result, the cost per child death averted was higher than for ITNs: USD 3,933-4,357. CONCLUSION: Both ITNs and IRS are highly cost-effective vector control strategies. Integrated ITN free distribution campaigns appeared to be the most efficient way to rapidly increase ITN coverage. Other approaches were as or more cost-effective, and appeared better suited to "keep-up" coverage levels. ITNs are more cost-effective than IRS for highly endemic settings, especially if high ITN coverage can be achieved with some demographic targeting.

Anterior cruciate ligament reconstruction graft harvesting: pitfalls and tips.

Surgical treatment for anterior cruciate ligament deficiency has relied predominantly on reconstruction with autografts. Grafts taken from patients' own central third of their patellar tendon, bone-patellar tendon bone, or one or more of the hamstring tendons, semitendinosus, and gracilis, constitute the majority of grafts used for these purposes. Although there is no single graft option that clearly outperforms another, an abundance of articles replete with complications associated with harvest and use are available from peer-reviewed journals. It is these complications and their prevention that will be addressed in the following chapter. The idea in mind is that the reader might adopt these techniques to improve their patient outcomes by minimizing, or eliminating, the ongoing problems that such complications produce.

Quick wins versus sustainability: options for the upscaling of insecticide-treated nets.

A review of the main elements determining strategic choices for the large-scale distribution of insecticide-treated nets (ITNs) clearly shows the need for multiple strategies. Mass distributions of free nets provide a unique opportunity to achieve quickly high coverage rates. However, there is also a need for additional approaches to 1) provide continuous provision of ITNs for newly pregnant women and their babies and 2) provide protection for the rest of the population. Targeted subsidies will continue to be an important tool to achieve the first objective, either through direct distribution of ITNs or through vouchers. To achieve objective 2, a strong and competitive commercial sector for ITNs seems to be a good option. It is clear that "one size doesn't fit all," and more experience needs to be gathered and shared. With planning and good promotion campaigns, these strategies can co-exist and re-enforce each other.

Broken promise? Taxes and tariffs on insecticide treated mosquito nets.

Seven years ago, the removal of taxes and tariffs on insecticide treated nets (ITNs) was considered one of the easiest resolutions for most countries to implement among the targets agreed upon at the African Summit on Roll Back Malaria in Abuja, Nigeria, on April 25, 2000. However, seven years later, 24 of the 39 Abuja signatories continue to impose taxes and tariffs on this life-saving tool. Taxes and tariffs significantly increase the price of an insecticide treated net, reduce affordability, and discourage the commercial sector from importing insecticide treated net products. Consequently, Roll Back Malaria partners are engaged in advocacy efforts to remove taxes and tariffs on insecticide treated nets in malaria-endemic countries of Africa. This viewpoint summarizes key obstacles to the removal of taxes and tariffs that have been identified through a review of country situations. To achieve the goal of producing and supplying more than 160 million insecticide treated nets needed to reach the revised Roll Back Malaria Partnership targets by 2010, tax and tariff reforms are urgently needed. Such reforms must be accompanied by country-specific systems to protect the poor (e.g., through voucher systems for vulnerable groups and other forms of targeted subsidies).

Incidences of frostbite in arthroscopic knee surgery postoperative cryotherapy rehabilitation.

A retrospective study of 4 cases of frostbite was undertaken to examine causes and to identify related contributory behaviors and circumstances. These patients underwent various surgical interventions before the onset of frostbite during similar postoperative care regimens. Surgical procedures included some of the following in each patient: lateral retinacular release, vastus medialis oblique muscle advancement, partial medial meniscectomy, chondromalacia patella, trochlea, medial and lateral femoral condyle debridement, lateral retinaculum release, and excision of medial plica. The mechanism of onset, development, and sites of frostbite were uniform in all patients. In every case, the sites were located in the area on top of the patella including some adjacent regions depending on the size of each injury. Frostbite locations were correlated with the part of the cryotherapy cold cuff device located on top of the patellar region. This cuff portion was originally designed to accommodate surgical trauma induced during autogenous bone-tendon-bone graft harvest in anterior cruciate ligament reconstruction surgery. Locating cryotherapy over this region assisted in minimizing pain and effusion for patients subsequent to distal patella bone plug harvest trauma. However, the requirement for use of the pad in the patella area for patients not undergoing anterior cruciate ligament reconstruction with autograft was found to be unnecessary and was the primary cause of frostbite in the cases presented here.

Are Perth metropolitan GPs prepared for common medical emergencies?

General practitioners are the first point of contact for many acutely ill patients requiring emergency treatment. Although relatively infrequent, providing the correct treatment in a timely fashion may be crucial. Yet GPs are often inadequately prepared to deal with acutely ill patients, being limited mainly by the availability of emergency equipment (Table 1) and a lack of emergency drugs.

A comparison of Plateletworks and platelet aggregometry for the assessment of aspirin-related platelet dysfunction in cardiac surgical patients.

OBJECTIVE: To compare the assessment of aspirin-related platelet dysfunction using Plateletworks (Helena Laboratories, Beaumont, TX), a new point-of-care platelet function analyzer, with turbidometric platelet aggregometry, in cardiac surgical patients. DESIGN: Prospective observational study. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Fifty consecutive adult patients undergoing elective cardiac surgery for coronary artery bypass grafting or cardiac valve replacement. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Platelet function was assessed by Plateletworks and turbidometric platelet aggregometry before the commencement of anesthesia. Collagen, 10 microg/mL, was used as the agonist for both techniques. The area under the receiver-operator curve for the identification of recent aspirin ingestion (or=72 hours) using Plateletworks was 0.58 (95% confidence interval [CI] 0.42-0.75) versus 0.77 (95% CI 0.61-0.95) for turbidometric platelet aggregometry. The Spearman correlation coefficient (rho) between preoperative Plateletworks trade mark and postoperative mediastinal blood loss was 0.07 (p = 0.58), and between preoperative turbidometric platelet aggregometry and postoperative mediastinal blood loss was -0.31 (p = 0.03). On completion of surgery, the correlation coefficients were 0.14 (p = 0.34) and -0.29 (p = 0.08), respectively. CONCLUSION: These findings suggest that Plateletworks is of limited use for the detection of aspirin-related platelet defects in cardiac surgical patients.

Posterolateral corner reconstruction.

One should suspect a compromise of the lateral structures when presented with a posterior cruciate ligament (PCL) injury, especially if grade III laxity is present. In our experience, if a combined injury to the PCL and posterolateral corner is diagnosed, a combined PCL and posterolateral reconstruction is needed to restore stability. This article describes a posterolateral reconstruction procedure. This procedure, when used in combination with an intra-articular PCL reconstruction, restores rotary and posterior knee stability. This procedure uses allograft tissue and interference screw fixation, although autograft tissue may be used.