Immuno-Thrombotic Complications of COVID-19: Implications for Timing of Surgery and Anticoagulation.

Early in the coronavirus disease 2019 (COVID-19) pandemic, global governing bodies prioritized transmissibility-based precautions and hospital capacity as the foundation for delay of elective procedures. As elective surgical volumes increased, convalescent COVID-19 patients faced increased postoperative morbidity and mortality and clinicians had limited evidence for stratifying individual risk in this population. Clear evidence now demonstrates that those recovering from COVID-19 have increased postoperative morbidity and mortality.

Fibrin Strands Will Grow from Soluble Fibrin and Hang Up in an In Vitro Microcirculatory Viscoelastic Model: Is This a Major Cause of COVID-19 Associated Coagulopathy?

Viscoelastic testing (VET) by both TEG and ROTEM has demonstrated hypercoagulability early in corona virus disease 2019 (COVID-19) associated coagulopathy (CAC). Additional VET studies demonstrated fibrinolytic shutdown late in a majority of severely ill COVID-19 patients with an associated elevation of d-dimer. Elevated d-dimer confirms that coagulation, followed by fibrinolysis, has occurred.

A macrophage attack culminating in microthromboses characterizes COVID 19 pneumonia.

Introduction: A neutrophilic infiltrate characterizes bacterial pneumonia. Macrophage infiltration is similarly characteristic of the viral pneumonia caused by SARS-CoV-2. These infiltrating macrophages, while phagocytic and capable of engulfing virus laden alveolar cells, are also rich in tissue factor-a thromboplastin.

Experiences and effects of telerehabilitation services for physiotherapy outpatients in a resource-constrained public health set-up in the backdrop of the COVID-19 pandemic: A proposal.

Background: The announcement of a national lockdown in South Africa had country-wide impact on the delivery of health services. Strategies included prioritisation of patients and protecting patients who were considered at risk, resulting in the need for cancellation and temporary termination of many outpatient therapy services. This necessitated the urgent need to come up with a way of delivering physiotherapy rehabilitation services to patients in a more non-traditional format.

Predicting neurosurgical clearance in the polytrauma patient with concomitant traumatic brain injury.

The goal of this study is to develop a model based on previously used prognostic predictors in traumatic brain injury (TBI) patients with polytrauma, which will facilitate the decision-making of whether to clear these patients for non-cranial surgery. Data of eligible patients was obtained from a trauma database at a Level I trauma and academic tertiary referral center in the United States. The number of days seen by the neurosurgical service prior to clearance, injury severity score (ISS), post-trauma day 0 (PTD 0) of Glasgow Coma Score (GCS), intracranial pressure (ICP) score and computed tomography (CT) score, as well as the changes in GCS, ICP score and CT score between PTD 0 and day of clearance were the variables used in developing the model.

Extreme Plasma Dilution Decreases Heparin and Protamine Cardiopulmonary Bypass Requirements: A Case Report on a Jehovah's Witness Patient.

The primary focus of cardiopulmonary bypass management in Jehovah's Witness patients is the need to conserve blood. A consequence of these strategies inevitably results in hemodilution that is frequently extreme enough to dilute clotting factors and potentially impair coagulation. The purpose of this case report is to demonstrate that a hemodiluted patient requires less heparin to sustain anticoagulation and less protamine to reverse heparin at cardiopulmonary bypass termination.

Crotalus atrox venom preconditioning increases plasma fibrinogen and reduces perioperative hemorrhage in a rat model of surgical brain injury.

Perioperative bleeding is a potentially devastating complication in neurosurgical patients, and plasma fibrinogen concentration has been identified as a potential modifiable risk factor for perioperative bleeding. The aim of this study was to evaluate preconditioning with Crotalus atrox venom (Cv-PC) as potential preventive therapy for reducing perioperative hemorrhage in the rodent model of surgical brain injury (SBI). C.

Supporting safe driving practices among consumers of mental health services: guidelines for assessment.

Driving is often omitted or ignored during assessment and ongoing work with consumers of mental health services. This Open Forum describes guidelines to help providers of psychiatric services to support safe driving practices among consumers. The guidelines were developed over seven years with contributions from a wide range of stakeholders.

Association of plasma dilution with cardiopulmonary bypass-associated bleeding and morbidity.

Objective: To investigate the relationship of cardiopulmonary bypass-associated plasma dilution with blood product transfusion and postoperative morbidity.

Design: Retrospective chart review.

Setting: Single academic medical center.

Inhibiting platelet-stimulated blood coagulation by inhibition of mitochondrial respiration.

Platelets are important mediators of blood coagulation that lack nuclei, but contain mitochondria. Although the presence of mitochondria in platelets has long been recognized, platelet mitochondrial function remains largely unaddressed. On the basis of a small amount of literature that suggests platelet mitochondria are functional, we hypothesized that the inhibition of platelet mitochondria disrupts platelet function and platelet-activated blood coagulation.

An algorithm for preventing bypass-associated dilutional (BAD) coagulopathy: Theory and example.

Crystalloid administered during cardiopulmonary bypass may significantly dilute clotting factor concentrations, particularly in low blood volume patients. Should the administered fluid (pump prime plus IVs) drop the clotting factor concentrations below approximately 38%, almost all patients will bleed, heparin levels will be overestimated and excessive neutralizing protamine will be administered. This combination can render blood virtually unclottable.

Statistical clues to postoperative blood loss: moving averages applied to medical data.

With the advent of computerized databases, medical data has become easy to accumulate; however, effective use of this data continues to pose significant problems. In other circumstances, smoothing algorithms have been used to uncover non-obvious correlations, trends and relationships in noisy data. We have applied four such algorithms to a large dataset of postoperative blood replacement in cardiopulmonary bypass patients.

Postoperative bypass bleeding: a bypass-associated dilutional (BAD) coagulopathy?

A number of associations with post-bypass bleeding have been described in the accompanying paper. Herein we hypothesize that dilution is an underlying cause through a malign series of bypass-associated events. Heparinized blood behaves anomalously when diluted.

Ratiometric single-nanoparticle oxygen sensors for biological imaging.

It makes sense: Conjugated polymer nanoparticles doped with a platinum porphyrin dye exhibit bright phosphorescence that is highly sensitive to the concentration of molecular oxygen. The small size, extraordinary brightness, excellent sensitivity, and ratiometric emission, together with the demonstration of single-particle sensing and cellular uptake, indicate the potential of the nanoparticle sensors for quantitative mapping of local molecular oxygen concentration.

Multicolor conjugated polymer dots for biological fluorescence imaging.

Highly fluorescent conjugated polymer dots were developed for demanding applications such as fluorescence imaging in live cells. These nanoparticles exhibit small particle diameters, extraordinary fluorescence brightness, and excellent photostability. Single particle fluorescence imaging and kinetic studies indicate much higher emission rates (approximately 10(8) s(-1)) and little or no blinking of the nanoparticles as compared to typical results for single dye molecules and quantum dots.

A survey of recruitment and retention issues for occupational therapists working clinically in mental health.

Background:   Mental health services Australia-wide have difficulty recruiting and retaining clinical occupational therapists.

Methods:   A survey of occupational therapists to identify factors that could influence their retention or loss from clinical mental health practice was undertaken.

Results:   Typically, respondents were female, aged 30 years or younger, working full-time at a grade 2 or 3 level, and had worked entirely in mental health.

Formal heparin anticoagulation protocol improves safety of charcoal-based liver-assist treatments.

Extracorporeal devices have had limited effectiveness in liver failure due to consequences of inadequate anticoagulation. The purpose of this study was to evaluate an anticoagulation protocol developed for Liver Dialysis Unit (LDU) treatments. Twelve patients underwent 19 LDU treatments for acetaminophen overdose (n = 1), subacute liver failure (n = 1), and refractory encephalopathy in cirrhosis (n = 10).

Reinfusion of aspirated pericardial blood during CPB. Part II. Laparotomy sponges are hazardous parts of the CPB circuit?

Usually, cotton laparotomy sponges are discarded when they become blood soaked. During bypass surgery, however, they are often wrung out into the pericardial sac and the contents of the sac are aspirated into the cardiopulmonary bypass (CPB) circuit. After cardiopulmonary bypass, many patients give evidence of mental confusion, excessive bleeding, and systemic inflammatory response syndrome (SIRS).

Reinfusion of aspirated pericardial blood during CPB. Part I. Hypothesis: laparotomy sponges are a significant part of the CPB circuit?

Blood accumulating in the pericardial sac is routinely reinfused during cardiopulmonary bypass (CPB) surgery. Such reinfusion has been associated with an increased incidence of serious complications such as coagulopathy, systemic inflammation, and neurologic sequelae. We hypothesize that some of these complications occur because the reinfused blood has been exposed to and activated by laparotomy sponges used to elevate the heart during vein graft emplacement.

Avoiding regression analysis pitfalls when calibrating white blood cell differential counters.

Method comparison and calibration are important for clinical hematologists and for manufacturers of new methods and instruments. Automation of the white blood cell (WBC) differential count poses unique problems in this regard because the reference method is a microscopic manual cell count of 200 WBCs. A highly variable reference method can obscure the true relation between the reference and the test methods and reduce sensitivity to miscalibration.

The effect of three commercial coaching courses on Step One USMLE performance.

Background: A substantial industry exists to provide formal review courses for Step 1 of the United States Medical Licensing Examination (USMLE). There are limited data on the usefulness of these courses.

Aim: To determine whether or not student participation in a commercial coaching course improves performance on Step 1 of the USMLE.

International Council for Standardization in Haematology (ICSH) recommendations for "surrogate reference" method for the packed cell volume.

The spun packed cell volume (PCV, hematocrit) is a key measurement on which are based hematology instrument calibration, reference range determination, and assignment of values to calibrators/controls. In 2001, the International Council for Standardization in Haematology (ICSH) recommended a Reference PCV method, which is fully traceable to the ICSH reference hemoglobin method. Because of its complexity, however, this method is impractical for occasional use in routine laboratories and is therefore intended primarily for use by manufacturers of capillary microhematocrit tubes, liquid calibrators, and multichannel analyzers.

Rapid-SF: a rapid whole-blood screen for soluble fibrin monomer.

Thrombosis accounts for a high proportion of disability and death in the West. Although soluble fibrin (SF) assays have been shown to be good predictors of thrombosis, current quantitative assays are too complex or lengthy to provide timely results, while simpler methods are qualitative and lack sensitivity. We here describe a rapid, new, protamine-based whole-blood screening method for SF which is quantitative and suitable for point-of-care use.

Control of analyzer slope and intercept in the measurement of packed red cell volume (PCV): part II.

A majority of packed cell volume (PCV) assays performed in the United States are performed by multichannel hematology analyzers rather than by centrifugation of blood samples in glass capillary tubes. PCV results from both analytical approaches were compared to the recently described ICSH reference method to determine the effect of assay slope on clinical utility. Though not controllable by the end user, the slope of the PCV assay versus the reference was satisfactory when performed in centrifuged glass capillaries.

Control of analyzer slope and intercept in the measurement of packed red cell volume (PCV): part I.

Five multichannel hematology analyzers (four different models) were evaluated to determine the ability of analyzers to correctly measure packed cell volume (PCV) values across the clinically relevant range. A sixth analyzer (fifth model) was subsequently included using archival data. Twenty-two different blood samples with PCVs ranging from 0.