Numerous published guidelines encourage appropriate use of fresh frozen plasma (FFP). However, adherence is documented as poor. Therefore, we sought to determine the laboratory effect of FFP administration to patients with an international normalized ratio (INR) less than 1.6 (prothrombin time < 1.6 times normal). We found minimally prolonged INRs decreased with treatment of the underlying disease alone. Adding FFP to the treatment failed to change the decrease in INR over time. In addition, we observed that the change in the INR per unit of FFP transfused can be predicted by the pretransfusion INR (INR change = 0.37 [pretransfusion INR] - 0.47; r2 = 0.82). With an observed analytic variation of 3.2%, a significant amount of change in the INR following FFP transfusion is expected at an INR of more than 1.7. Indeed, only 50% of patients with an INR of 1.7 showed a significant change in INR with FFP transfusion. Therefore, transfusion for patients not meeting current FFP guidelines does not reliably reduce the INR and exposes patients to unnecessary risk.

Three-factor PCC does not satisfactorily lower ST-INR due to low FVII content. Infusion of a small amount of plasma increases the likelihood of satisfactory INR lowering.

Previous studies have demonstrated that prior synaptic activity can influence the subsequent induction of synaptic plasticity in the brain. Such temporal modulation of synaptic plasticity has been called "metaplasticity." In this report, we describe the facilitatory effects of high-frequency stimulation on the induction of homosynaptic long-term depression (LTD) in the CA1 region of the rat hippocampus. The LTD induced by low-frequency stimulation (1 Hz) protocols was found to be homosynaptic and NMDA receptor-dependent. The facilitatory effects of the high-frequency stimulation-induced priming event itself were found to be NMDA receptor-independent and to have a duration of at least 90 min. The effects of priming also were heterosynaptic, because the induction of synaptic plasticity by low-frequency stimulation was enhanced at an unprimed synaptic pathway after the priming of an independent pathway. In addition to enhancing LTD, priming also enhanced the reversal of long-term potentiation elicited by a 5 Hz depotentiation protocol. Our results provide examples of how metaplasticity may play a key role in the ongoing modulation of the induction and stabilization of alterations in synaptic strength.

Poor core laboratory performance that causes delays in diagnosis and treatment is an impediment to optimal patient care, particularly in high-volume patient care areas such as the emergency department (ED). To evaluate the impact of laboratory performance on patient care outcomes, we obtained data from 11 hospitals related to laboratory test turnaround time (TAT) parameters and ED patient throughput. We observed that the average length of stay (LOS) in the ED correlated significantly with the percentage of total laboratory outliers (R2 = 0.75; P < .01) and to a lesser extent the TAT means (R2 = 0.66; P < .01). Furthermore, improvements in laboratory performance during the study were associated with concurrent decreases in ED LOS. Although in the past, laboratories have focused on TAT means for performance assessment, our observations suggest that a more appropriate method of benchmarking might be to aggressively set clinically driven TAT targets and assess performance as the percentage of results achieving this goal.