Medication Errors in Injured Patients

Trauma patients are vulnerable to medication error given multiple handoffs throughout the hospital. The purpose of this study was to assess trends in medication errors in trauma patients and the role these errors play in patient outcomes. Injured adults admitted from 2009 to 2015 to a Level I trauma center were included. Medication errors were determined based on a nurse-driven, validated, and prospectively maintained database. Multivariable logistic regression modeling was used to control for differences between groups. Among 15,635 injured adults admitted during the study period, 132 patients experienced 243 errors. Patients who experienced errors had significantly worse injury severity, lower Glasgow Coma Scale scores and higher rates of hypotension on admission, and longer lengths of stay. Before adjustment, mortality was similar between groups but morbidity was higher in the medication error group. After risk adjustment, there were no significant differences in morbidity or mortality between the groups. Medication errors in trauma patients tend to occur in significantly injured patients with long hospital stays. Appropriate adjustment when studying the impact of medical errors on patient outcomes is important

Effects of graphite nodules on crack growth behaviour of austempered ductile iron

Austempered ductile iron (ADI) is a candidate material for camshafts, where however, the early stages of fatigue damage are of major concern during service. A fundamental microstructurally based assessment of the mechanisms of fatigue failure is important. An ADI microstructure austenitised at 900°C and austempered at 390°C has been investigated in detail. Crack initiation and growth behaviour was assessed under three-point bend testing conditions. Primary initiation events occurred exclusively at pores with further micro-crack initiation occurring at decohered graphite nodules in the monotonic plastic zone ahead of the advancing dominant macro-crack tip. Lifetime was however determined by propagation behaviour rather than coalescence events. The changes in the as-cast microstructure generated by this heat treatment have resulted in improved fatigue crack propagation performance due to the reduction in eutectic carbides and the relatively high quantity of retained austenite compared with previous studies, giving rise to greater crack path tortuousity and shielding

Effects of carbides on fatigue characteristics of austempered ductile iron

Crack initiation and growth behavior of an austempered ductile iron (ADI) austenitized at 800 °C and austempered at 260 °C have been assessed under three-point bend fatigue conditions. Initiation sites have been identified as carbides remaining from the as-cast ductile iron due to insufficient austenization. The number of carbides cracking on loading to stresses greater than 275 MPa is critical in determining the failure mechanism. In general, high carbide area fractions promote coalescence-dominated fatigue crack failure, while low area fractions promote propagation-dominated fatigue crack failure. Individual carbides have been characterized using finite body tessellation (FBT) and adaptive numerical modeling (SUpport vector Parsimonious ANalysis Of VAriance (SUPANOVA)) techniques in an attempt to quantify the factors promoting carbide fracture. This indicated that large or long and thin carbides on the whole appear to be susceptible to fracture, and carbides that are locally clustered and aligned perpendicular to the tensile axis are particularly susceptible to fracture