Evaluation of ventricular-vascular coupling with critical care metrics: An in silico approach.

Mean arterial pressure and cardiac output provide insufficient guidance for the management of intraoperative hypotension (IOH). In silico models offer additional insights into acute changes in hemodynamic parameters that may be encountered during IOH. A computational model (CM) generated parameters quantifying ventricular-vascular coupling, and pressure-volume construct across levels of aortic compliance (CA ). We studied how a loss from normal-to-stiff CA impacts critical care metrics of hemodynamics during vascular occlusion. Pulse pressure (PP), end-systolic pressure (Pes ), arterial compliance (Art-ca), arterial elastance (Art-ea), and dynamic arterial elastance (Eadyn), along mechanical efficiency (ME) were measured at five levels of CA . A loss in CA impacted all variables. During steady-state conditions, PP, Pes , and stroke work increased significantly as CA decreased. Art-ca decreased and Art-ea increased similarly; Eadyn increased and ME decreased. During a decrease in preload across all CA levels, arterial dynamics measures remained linear. The CM demonstrated that a loss in CA impacts measures of arterial dynamics during steady-state and transient conditions and the model demonstrates that critical care metrics are sensitive to changes in CA . While Art-ca and Art-ea were sensitive to changes in preload, Eadyn did not change.

Intraosseous Lipoma: An Elusive Cause of Long Bone Pain: A Case Series.

Introduction: Intraosseous lipomas are benign tumors composed of mature fat that reside within the intramedullary canal. Although many cases are asymptomatic, some patients report pain that interferes with daily living. For patients presenting with refractory pain, surgical excision may be performed. These tumors were once thought to be rare, but a recent increase in awareness and diagnostic capability may contradict this. Case Presentations: A 27-year-old female presented with a 3-month history of deep and aching pain in her left shoulder. The second patient was a 24-year-old female who presented with a 3-year history of pain in her right tibia. The third was a 50 year old female who presented with a 4-month history of deep pain in her right humerus. The fourth patient was a 34-year-old female who presented with a 6-month history of the left heel pain. All were found to have intraosseous lipomas and were treated with excisional curettage, achieving resolution of symptoms. Conclusion: These cases may help orthopedists better understand the presentation and treatment of intraosseous lipomas due to several shared characteristics. We also hope that this report may lead clinicians to include this pathology in their differential diagnosis when patients present with similar symptoms. As the prevalence of these tumors appears to be increasing, efficient diagnosis and treatment will become increasingly valuable to orthopedists and patients.