LAUSR

Introduction/Hypothesis: Using Central Venous Pressure (CVP) as a surrogate for Intra-Vascular Volume (IVV) status has been widely used for many years and evaluated by many studies. Using Bedside Ultrasound (BU) evaluation of IVV status and comparing it to CVP is the purpose of this study. Methods: This was a prospective, observational study in the surgical ICU of a single academic tertiary care center. Patients with low IVV status determined by BU as well as SM parameters had their CVP observed and measured. BU evaluation included evaluating the heart, lungs, Inferior Vena Cava (IVC) and the Internal Jugular Vein (IJV). The SM included evaluating the heart rate, mean arterial pressure, serum lactate, Oxygen Saturation of central venous blood (SCVO2), and cardiac index. BU and SM evaluation was compared to the CVP. Results: 76 patients in the ICU were included in the study. Forty six (59%) were male, 50 (64%) were Caucasian and mean age was 57.5 years± 15.9. 20 patients had a CVP < 8 cm H2O, of which 18 (90%) were found to have low IVV status using BU and the SM. 56 patients had a CVP > 8 cm H2O and were found not to have low IVV status using BU and the SM. Youden’s index was used to find the optimal cutoff of CVP on hypovolemia by SM, CVP cutoff=8 had a Sensitivity=0.78 and a specificity=0.96. Also Youden’s index was used to find the optimal cutoff of CVP on hypovolemia by BU, CVP cutoff=8, Sensitivity=0.75, specificity=0.96. Cutoff for CVP of 8 is calculated from maximizing Youden index. When using BU and the SM for evaluation of IVV status, patients with hypovolemia who had a 75 folds risk of hypovolemia when their CVP was < 8 compared to CVP > 8. (OR=75 (14-406), p<0.001). Conclusions: Using BU to assess the IVV status correlates with CVP in hypovolemia. A diagnosis of hypovolemia using BU significantly correlates with a CVP< 8 and had a higher risk of hypovolemia compared to CVP> 8. Introduction/Hypothesis: The American Heart Association (AHA) Advanced Cardiac Life Support (ACLS) guidelines emphasize the importance of early defibrillation for shockable rhythms. It has been shown that each 5-second increase in preshock pause leads to an 18% decrease in survival to discharge. Current AHA guidelines involve a pause for rhythm check and a pause for shock delivery, if indicated. Pre-charging the defibrillator before the pulse check has the potential to reduce the latter pause. People considering this technique have expressed concern about inadvertent shocks. This study aims to evaluate the impact of pre-charging the defibrillator on time to shock delivery. Methods: Rising second year Internal Medicine Residents (n=46) were randomized to two arms for a simulation session. Both arms consisted of 4 groups of 5-7 residents who underwent 7 simulation cases. The control arm followed current ACLS guidelines. The intervention arm was instructed to pre-charge the defibrillator 20 seconds prior to pausing chest compressions for a rhythm/pulse check. Time to shock, compression fraction, chest compression interruptions, appropriateness of shocks delivered, safety of shocks, time to return of spontaneous circulation (ROSC), time to first medication, and time to bag-mask-ventilation were assessed. Results: The intervention group was significantly faster at delivering an appropriate shock (16.68s vs. 45.50s, p=0.049). Between the intervention and control group, there was no significant difference in compression fraction (85.8% vs. 85.8%, p=0.98), number of interruptions to chest compressions per case (3.2 vs. 3.9, p=0.27), overall number of inadvertent shocks delivered (0 vs. 0, p=1.0), number of inappropriate shocks administered (2 vs. 1, p=0.71), or number of shocks missed when indicated (5 vs. 7, p=0.84). Other outcomes including time to first medication, time to bag-mask-ventilation, and time to ROSC were similar between the groups. Conclusions: This study demonstrates that residents instructed to pre-charge the defibrillator were quicker to administer an appropriate shock, suggesting that instructing participants prior to ACLS training sessions about pre-charging the defibrillator may improve performance. There were no harms associated with pre-charging the defibrillator. 1501