The effect of targeted temperature management on coagulation parameters and bleeding events after out-of-hospital cardiac arrest of presumed cardiac cause

Temperature Control in Acute Brain Injury: An Update

Temperature control in severe acute brain injury (SABI) is a key component of acute management. This manuscript delves into the complex role of temperature management in SABI, encompassing conditions like traumatic brain injury (TBI), acute ischemic stroke (AIS), intracerebral hemorrhage (ICH), aneurysmal subarachnoid hemorrhage (aSAH), and hypoxemic/ischemic brain injury following cardiac arrest. Fever is a common complication in SABI and is linked to worse neurological outcomes due to increased inflammatory responses and intracranial pressure (ICP). Temperature management, particularly hypothermic temperature control (HTC), appears to mitigate these adverse effects primarily by reducing cerebral metabolic demand and dampening inflammatory pathways. However, the effectiveness of HTC varies across different SABI conditions. In the context of post-cardiac arrest, the impact of HTC on neurological outcomes has shown inconsistent results. In cases of TBI, HTC seems promising for reducing ICP, but its influence on long-term outcomes remains uncertain. For AIS, clinical trials have yet to conclusively demonstrate the benefits of HTC, despite encouraging preclinical evidence. This variability in efficacy is also observed in ICH, aSAH, bacterial meningitis, and status epilepticus. In pediatric and neonatal populations, while HTC shows significant benefits in hypoxic-ischemic encephalopathy, its effectiveness in other brain injuries is mixed. Although the theoretical basis for employing temperature control, especially HTC, is strong, the clinical outcomes differ among various SABI subtypes. The current consensus indicates that fever prevention is beneficial across the board, but the application and effectiveness of HTC are more nuanced, underscoring the need for further research to establish optimal temperature management strategies. Here we provide an overview of the clinical evidence surrounding the use of temperature control in various types of SABI.

Factors influencing deviation from target temperature during targeted temperature management in postcardiac arrest patients

BACKGROUND

Targeted temperature management (TTM) is a recommended therapy for postcardiac arrest patients. Hyperthermia worsened the patient outcome, and overcooling increased the incidence of complications; therefore, a high-quality TTM is required. The target temperature tended to be modified worldwide after the TTM trial in 2013. Our institute modified the target temperature to 35°C in 2017. This study aimed to compare the conventional and modified protocols, assess the relationship between target temperature deviation and patient outcomes, and identify the factors influencing temperature deviation.

METHODS

This single-centre, retrospective, observational study included adult out-of-hospital cardiac arrest patients who underwent TTM between April 2013 and October 2019. We compared the conventional and modified protocol groups to evaluate the difference in the background characteristics and details on TTM. Subsequently, we assessed the relationship of deviation (>±0.5°C, >37°C, or<33°C) rates from the target temperature with mortality and neurological outcomes. We assessed the factors that influenced the deviation from the target temperature.

RESULTS

Temperature deviation was frequently observed in the conventional protocol group (p=0.012), and the modified protocol group required higher doses of neuromuscular blocking agents (NMBAs) during TTM (p=0.016). Other background data, completion of protocol, incidence of complications, mortality and rate of favourable neurological outcomes were not significantly different. The performance rate of TTM was significantly higher in the modified group than in the conventional protocol group (p<0.001). Temperature deviation did not have an impact on the outcomes. Age, sex, body surface area, NMBA doses and type of cooling device were the factors influencing temperature deviation.

CONCLUSIONS

A target temperature of 35°C might be acceptable and easily attainable if shivering of the patients was well controlled using NMBAs. Temperature deviation did not have an impact on outcomes. The identified factors influencing deviation from target temperature might be useful for ensuring a high-quality TTM.

Comparison of Clopidogrel Versus Ticagrelor for Percutaneous Coronary Intervention (PCI) Patients Managed with Therapeutic Hypothermia: A Systematic Review and Meta-Analysis

Various antiplatelet drugs, such as clopidogrel and ticagrelor, are available on the market for use after percutaneous coronary intervention (PCI). However, the efficacy of such drugs in patients being managed with therapeutic hypothermia (TH) has always been debated. In light of this controversy, this systematic review and meta-analysis was performed to enhance existing literature. Various databases were searched for potentially relevant studies from inception to April 2023, including PubMed, Cochrane Library, and Scopus. The risk of bias was assessed using the Newcastle-Ottawa scale for cohort studies and the Cochrane risk of bias tool for randomized controlled trials. Outcomes of interest included risk of bleeding, stent thrombosis, and all-cause mortality. Five studies were shortlisted for inclusion into the meta-analysis, featuring a total of 245 patients receiving either clopidogrel or ticagrelor. Overall, no significant differences were noted when the use of clopidogrel and ticagrelor was compared in PCI patients being managed with TH. To the best of our knowledge, this is the most comprehensive meta-analysis comparing the outcomes of clopidogrel and ticagrelor in PCI patients being managed with TH. Despite existing studies claiming an altered efficacy of clopidogrel in such conditions, our meta-analytic findings could not prove this relationship. Due to the limited sample size, further comprehensive and randomized studies are encouraged to arrive at a robust conclusion.

Mild induced hypothermia and coagulation and platelet function in patients with septic shock: Secondary outcome of a randomized trial

Coagulation abnormalities and microthrombi contribute to septic shock, but the impact of body temperature regulation on coagulation in patients with sepsis is unknown. We tested the hypothesis that mild induced hypothermia reduces coagulation and platelet aggregation in patients with septic shock. Secondary analysis of randomized controlled trial. Adult patients with septic shock who required mechanical ventilation from eight intensive care units in Denmark were randomly assigned to mild induced hypothermia for 24 h or routine thermal management. Viscoelastography and platelet aggregation were assessed at trial inclusion, after 12 h of thermal management, and 24 h after inclusion. A total of 326 patients were randomized to mild induced hypothermia (n = 163) or routine thermal management (n = 163). Mild induced hypothermia slightly prolonged activated partial thromboplastin time and thrombus initiation time (R time 8.0 min [interquartile range, IQR 6.6-11.1] vs. 7.2 min [IQR 5.8-9.2]; p = .004) and marginally inhibited thrombus propagation (angle 68° [IQR 59-73] vs. 71° [IQR 63-75]; p = .014). The effect was also present after 24 h. Clot strength remained unaffected (MA 71 mm [IQR 66-76] with mild induced hypothermia vs. 72 mm (65-77) with routine thermal management, p = .9). The proportion of patients with hyperfibrinolysis was not affected (0.7% vs. 3.3%; p = .19), but the proportion of patients with no fibrinolysis was high in the mild hypothermia group (8.8% vs. 40.4%; p < .001). The mild induced hypothermia group had lower platelet aggregation: ASPI 85U (IQR 50-113) versus 109U (IQR 74-148, p < .001), ADP 61U (IQR 40-83) versus 79 U (IQR 54-101, p < .001), TRAP 108 (IQR 83-154) versus 119 (IQR 94-146, p = .042) and COL 50U (IQR 34-66) versus 67U (IQR 46-92, p < .001). In patients with septic shock, mild induced hypothermia slightly impaired clot initiation, but did not change clot strength. Platelet aggregation was slightly impaired. The effect of mild induced hypothermia on viscoelastography and platelet aggregation was however not in a range that would have clinical implications. We did observe a substantial reduction in fibrinolysis.

Temperature Control After Cardiac Arrest: A Narrative Review

Cardiac arrest (CA) is a critical public health issue affecting more than half a million Americans annually. The main determinant of outcome post-CA is hypoxic-ischemic brain injury (HIBI), and temperature control is currently the only evidence-based, guideline-recommended intervention targeting secondary brain injury. Temperature control is a key component of a post-CA care bundle; however, conflicting evidence challenges its wide implementation across the vastly heterogeneous population of CA survivors. Here, we critically appraise the available literature on temperature control in HIBI, detail how the evidence has been integrated into clinical practice, and highlight the complications associated with its use and the timing of neuroprognostication after CA. Future clinical trials evaluating different temperature targets, rates of rewarming, duration of cooling, and identifying which patient phenotype benefits from different temperature control methods are needed to address these prevailing knowledge gaps.

Association of Histones With Coagulofibrinolytic Responses and Organ Dysfunction in Adult Post-cardiac Arrest Syndrome

Background

Patients successfully resuscitated from cardiac arrest often develop organ dysfunction caused by systemic inflammation and increased coagulation, leading to disseminated intravascular coagulation (DIC). The involvement of histones in DIC and organ dysfunction in patients with sepsis and trauma has been previously reported, raising the probability that histones may also be associated with pathophysiology in patients after cardiac arrest and resuscitation. This study evaluated the relationship between histones and organ dysfunction related to coagulofibrinolytic changes in patients with post-cardiac arrest syndrome (PCAS).

Methods

This prospective single-center observational study assessed 35 adult patients with PCAS who were divided into two groups, i.e., 15 patients with multiple organ dysfunction syndrome (MODS) and 20 patients without MODS. MODS was defined as a sequential organ failure assessment score of ≥12. The plasma levels of histones and coagulofibrinolytic markers, including soluble fibrin, tissue-type plasminogen activator, plasminogen activator inhibitor-1, plasmin-alpha 2-plasmin inhibitor complex (PIC), and soluble thrombomodulin, were measured in patients with PCAS immediately after admission to the emergency department, and 3 and 24 h after arriving at the hospital.

Results

PCAS patients with MODS had higher DIC scores [4 (3.0–5.0) vs. 1 (0.0–3.0), p = 0.012] and higher mortality rates (66.7% vs. 20.0%, p = 0.013) than those without MODS. Moreover, patients with MODS exhibited higher histone levels than those without MODS during the early phase of the post-resuscitation period. Severe endothelial injury and higher thrombin and plasmin generation were observed in the MODS group. Plasma levels of histones were positively correlated with those of soluble fibrin immediately after resuscitation (rho = 0.367, p = 0.030) and PIC 3 h after arriving at the hospital (rho = 0.480, p = 0.005). This correlation was prominent in the patient population with MODS (soluble fibrin: rho = 0.681, p = 0.005, PIC: rho = 0.742, p = 0.002).

Conclusions

This study demonstrated that elevated histone levels were associated with increased levels of thrombin, and subsequent plasmin generation in PCAS patients, especially those with MODS. Further studies are required to elucidate the causal relationship between histones and organ dysfunction related to DIC in PCAS.

Mild Therapeutic Hypothermia Alters Hemostasis in ST Elevation Myocardial Infarction Patients

Background and Rationale: Mild therapeutic hypothermia (MTH) is a concept to reduce infarct size and improve outcome after ST-segment elevation myocardial infarction (STEMI). In the STATIM trial, we investigated MTH as an additional therapy for STEMI patients. In the intention-to-treat set, 101 patients were included. No difference in primary and secondary endpoints measured by cardiac magnetic resonance imaging was found. Platelet activation and plasmatic coagulation are key in the pathophysiology of STEMI. In the present study, we investigated the effect of MTH on primary and secondary hemostasis in STEMI patients.

Methods and Results: Platelet function and morphology were assessed by routine blood count, aggregometry testing, and flow cytometry. Soluble platelet markers were determined by enzyme-linked immunosorbent assay (ELISA) testing. Plasmatic coagulation was measured throughout the study. Platelet count remained unchanged, irrespective of treatment, whereas platelet size decreased in both patient groups. Platelet aggregometry indicated increased platelet reactivity in the MTH group. Furthermore, higher adenosine diphosphate (ADP) plasma levels were found in MTH patients. Expression of glycoprotein IIb/IIIa was increased on platelets of STEMI patients treated with MTH. Lower patient temperatures correlated with longer clotting times and resulted in reduced pH. Lower pH values were positively correlated with longer clotting times.

Conclusion: Present data indicate longer clotting times and higher platelet reactivity in STEMI patients treated with MTH. These changes did not correspond to clinical bleeding events or larger infarct size.

ST-Elevation Myocardial Infarction Complicated by Out-of-Hospital Cardiac Arrest

5-10% of ST-elevated myocardial infarctions (STEMI) present with out-of-hospital cardiac arrest (OHCA). Although this subgroup of patients carries the highest in-hospital mortality among the STEMI population, it is the least likely to undergo coronary angiography and revascularization. Due to the concomitant neurologic injury, patients with OHCA STEMI require prolonged hospitalization and adjustments to standard MI management. This review systematically assesses the course of patients with OHCA STEMI from development of the arrest to hospital discharge, assesses the limiting factors for their treatment access, and presents the evidence-based optimal intervention strategy for this high-risk MI population.

Management of out-of hospital cardiac arrest patients with extracorporeal cardiopulmonary resuscitation in 2021

INTRODUCTION

Over the last decade, eCPR programs have become more and more popular, at least amongst high-volume centers. Despite its rise in popularity and promising outcome, strategies concerning pre- and post-implantation of VA-ECMO remain at least debatable. Besides, integrating the appropriate set-up, managing anticoagulation, implementing LV-venting, and predicting neurological outcome play important roles in caring for thise highly selective patient-collective. We sought to present our institutional´s techniques for establishing an eCPR program and managing patients peri- and post implantation in eCPR-runs.

AREAS COVERED

This manuscript covers the majority of clinical concerns and parameters for establishing an eCPR program and its recent advantages. We will describe a safe way of cannulation, setting anticoagulation goals, strategies for LV-venting and ICU-treatment. Also included, an elaboration on neurological and cardiac prognostication.

EXPERT OPINION

We advocate ultrasound-guided cannula placement in eCPR patients. Also, we emphasize the importance of using stiffer wires and smaller arterial cannula sizes due to the different physiological parameters of OHCA patients. After cannulation, we aim for lower flow goals, the concept of 'partial VA-ECMO,' and lower anticoagulatory targets. LV-venting with Impella should remain an individual case to case decision.

Practical considerations for postarrest targeted temperature management

Out-of-hospital cardiac arrest remains a major challenge worldwide, with survival to discharge rates of <20% in the great majority of countries. Advancements in prehospital care, including increasing deployment of automated external defibrillators and improvements in bystander cardiopulmonary resuscitation, have led to more victims achieving return of spontaneous circulation (ROSC), yet the majority of patients with ROSC suffer in-hospital mortality or significant neurologic injuries that persist after discharge. This postarrest morbidity and mortality is largely due to a complex syndrome of mitochondrial dysfunction, inflammatory cascades and cellular injuries known as the postcardiac arrest syndrome (PCAS). The management of PCAS represents a formidable task for emergency and critical care providers. A cornerstone of PCAS treatment is the use of aggressive core body temperature control using thermostatically controlled devices, known as targeted temperature management (TTM). This therapy, demonstrated to be effective in improving both survival and neurologic recovery by several randomized controlled trials nearly 20 years ago, remains a major topic of clinical investigation. Important practical questions about TTM remain: How soon must providers initiate the therapy? What TTM goal temperature maximizes benefit while limiting potential adverse effects? How long should TTM therapy be continued in patients following resuscitation? In this review, we will address these issues and summarize clinical research over the past decade that has added to our fund of knowledge surrounding this important treatment of patients following cardiac arrest.

Lund University Cardiac Assist System Induced Liver Laceration and Anterior Cord Infarction After Cardiac Arrest: A Case Report

We describe a hepatic laceration and subsequent anterior spinal artery syndrome in a 21-year-old man, secondary to prolonged cardiopulmonary resuscitation with a Lund University Cardiac Assist System (LUCAS2) mechanical cardiac compression device. We briefly review the current literature pertaining to hepatic injury from trauma due to cardiopulmonary resuscitation. The etiology of the anterior spinal artery syndrome in this patient is discussed. This case highlights that intra-abdominal causes of hypotension should be considered in patients after a prolonged resuscitation attempt. Extending focused cardiac ultrasound to exclude intra-abdominal free fluid should be routinely considered in these patients.

Thromboelastography to Assess Coagulopathy in Traumatic Brain Injury Patients Undergoing Therapeutic Hypothermia

Therapeutic hypothermia has been a treatment option for patients with severe traumatic brain injury (TBI) for many years. There has, however, been uncertainty whether hypothermia in this context also increased clinical bleeding risk, perhaps due to platelet dysfunction. Standard coagulation tests do not allow accurate assessment of in vivo coagulation. We studied specific coagulation abnormalities in patients undergoing therapeutic hypothermia for severe TBI using bedside thromboelastography (TEG).We studied 20 patients with severe blunt TBI from a single tertiary ICU who were enrolled in the prophylactic hypothermia to lessen traumatic brain injury (POLAR) trial. Ten patients had been randomized to hypothermia, and 10 were controls receiving normothermic standard care. TEG was undertaken during and after therapeutic hypothermia, and at the same time points in controls. Coagulation profiles were then compared between the hypothermic and control patients, and also between hypothermia and later normothermia in the study patients. Patients were primarily young (mean age 34 years) and male (85%). Measures of injury severity, including Glasgow coma score and injury severity scale, were not different between groups. Using TEG, the median alpha angle was reduced in hypothermic patients compared with controls (69.2° vs. 72.0°, p = 0.02), although both were within the normal range. LY30 was also reduced (0.0% vs. 0.5%, p < 0.01). Both differences persisted when hypothermic patients were compared with themselves during later normothermia. Therapeutic hypothermia during severe TBI causes a small decrease in the rate of clot formation. However, this decrease is within the normal range, and is unlikely to be clinically significant.

Prognostic value of repeated thromboelastography measurement for favorable neurologic outcome during targeted temperature management in out-of-hospital cardiac arrest survivors

BACKGROUND

Cardiac arrest can activate blood coagulation, which clinically manifests as obstruction of the microcirculation and multiple organ dysfunction. Thromboelastography (TEG) provides a rapid and comprehensive assessment of hemostatic processes, but there are limited data on the use of sequential TEG values during targeted temperature management (TTM) in out-of-hospital cardiac arrest (OHCA) survivors. The aim of this study was to investigate the prognostic value of coagulopathy assessed by repeated TEG to predict neurologically intact survival.

METHODS

A prospective cohort of consecutive non-trauma OHCA patients who were successfully resuscitated and treated with TTM. Patients with a target temperature of 36 ℃, no TEG data, and who declined appropriate treatment were excluded. TEG was measured at three time points of TTM (initial phase, target phase, and rewarming phase). The primary outcome was 28 day favorable neurologic function, defined as a Cerebral Performance Category of 1 or 2.

RESULTS

A total of 125 patients (mean age, 61 years; 63.2% male) were analyzed. A favorable neurologic outcome at 28 days was seen in 40 patients (32.0%). TEG values of R and LY30 in the initial phase were significantly lower in the favorable neurologic outcome group than in the unfavorable group (5.8 vs. 8.1 and 0.1 vs. 0.7, respectively; p < 0.01). TEG values of R < 5 or LY30 < 7.5 in the initial phase were more frequently seen in the favorable outcomes group than in the unfavorable group (37.5% vs. 12.9%, p = 0.002 and 95.0% vs. 72.9%, p = 0.004, respectively). However, no significant differences were seen between the two groups in other TEG values (R, K, alpha, and MA) in the target and rewarming phases (p > 0.05 for all). Univariate analysis showed higher D-dimer levels, prothrombin time, and activated partial thromboplastin time in the unfavorable outcome group. In the multivariable analysis, TEG values of combination of R < 5 and LY30 < 7.5 in the initial phase were the only coagulation profiles seen to be independently associated with favorable neurologic outcome (OR, 4.508, 95% CI, 1.254-16.210).

CONCLUSION

TEG results are available within minutes, and shorted R values or the absence of prolonged LY30 values in the initial phase are an early predictor of neurologically intact survival in successfully resuscitated OHCA patients.

Effect of hypothermia on haemostasis and bleeding risk: a narrative review

It must be remembered that clinically important haemostasis occurs in vivo and not in a tube, and that variables such as the number of bleeding events and bleeding volume are more robust measures of bleeding risk than the results of analyses.

In this narrative review, we highlight trauma, surgery, and mild induced hypothermia as three clinically important situations in which the effects of hypothermia on haemostasis are important. In observational studies of trauma, hypothermia (body temperature <35°C) has demonstrated an association with mortality and morbidity, perhaps owing to its effect on haemostatic functions. Randomised trials have shown that hypothermia causes increased bleeding during surgery. Although causality between hypothermia and bleeding risk has not been well established, there is a clear association between hypothermia and negative outcomes in connection with trauma, surgery, and accidental hypothermia; thus, it is crucial to rewarm patients in these clinical situations without delay. Mild induced hypothermia to ≥33°C for 24 hours does not seem to be associated with either decreased total haemostasis or increased bleeding risk.

Postresuscitation Care after Out-of-hospital Cardiac Arrest: Clinical Update and Focus on Targeted Temperature Management

Out-of-hospital cardiac arrest is a major cause of mortality and morbidity worldwide. With the introduction of targeted temperature management more than a decade ago, postresuscitation care has attracted increased attention. In the present review, we discuss best practice hospital management of unconscious out-of-hospital cardiac arrest patients with a special focus on targeted temperature management. What is termed post-cardiac arrest syndrome strikes all organs and mandates access to specialized intensive care. All patients need a secured airway, and most patients need hemodynamic support with fluids and/or vasopressors. Furthermore, immediate coronary angiography and percutaneous coronary intervention, when indicated, has become an essential part of the postresuscitation treatment. Targeted temperature management with controlled sedation and mechanical ventilation is the most important neuroprotective strategy to take. Targeted temperature management should be initiated as quickly as possible, and according to international guidelines, it should be maintained at 32° to 36°C for at least 24 h, whereas rewarming should not increase more than 0.5°C per hour. However, uncertainty remains regarding targeted temperature management components, warranting further research into the optimal cooling rate, target temperature, duration of cooling, and the rewarming rate. Moreover, targeted temperature management is linked to some adverse effects. The risk of infection and bleeding is moderately increased, as is the risk of hypokalemia and magnesemia. Circulation needs to be monitored invasively and any deviances corrected in a timely fashion. Outcome prediction in the individual patient is challenging, and a self-fulfilling prophecy poses a real threat to early prognostication based on clinical assessment alone. Therefore, delayed and multimodal prognostication is now considered a key element of postresuscitation care. Finally, modern postresuscitation care can produce good outcomes in the majority of patients but requires major diagnostic and therapeutic resources and specific training. Hence, recent international guidelines strongly recommend the implementation of regional prehospital resuscitation systems with integrated and specialized cardiac arrest centers.

Targeted temperature management in patients undergoing extracorporeal life support after out-of-hospital cardiac arrest: an EURO-ELSO 2018 annual conference survey

Targeted temperature management and extracorporeal life support, particularly extracorporeal membrane oxygenation in patients undergoing cardiopulmonary resuscitation, represent outcome-enhancing strategies for patients following in- and out-of-hospital cardiac arrest. Although targeted temperature management with hypothermia between 32°C and 34°C and extracorporeal cardiopulmonary resuscitation bear separate potentials to improve outcome after out-of-hospital cardiac arrest, each is associated with bleeding risk and risk of infection. Whether the combination imposes excessive risk on patients is, however, unknown.

Time course of platelet counts in relation to the neurologic outcome in patients undergoing targeted temperature management after cardiac arrest

BACKGROUND

Thrombocytopenia is common and associated with mortality in critically ill patients. However, the time course of platelet counts and its association with the neurologic outcome after out-of-hospital cardiac arrest (OHCA) are not well known. The purpose of this study is to describe the time course of platelet counts in relation to the neurologic outcome in patients undergoing targeted temperature management (TTM) after CA.

METHODS

Review of consecutive patients receiving TTM after out-of-hospital CA between 2009 and 2016. The blood sample was collected daily until 7 days. The primary outcome was poor neurologic outcome at 6 months after CA defined as Cerebral Performance Category of 3-5 and secondary outcome was mortality at 6 months.

RESULTS

A total of 261 consecutive patients treated with TTM after OHCA between 2009 and 2016. One hundred seventy-five patients (67.0%) had poor neurologic outcomes 6 months after CA. The changes in the platelet counts over time between the good and poor outcome groups were statistically significant (p < 0.001). The platelet counts declined during TTM in both groups. The platelet counts recovered to the normal range at the end of the first week in the good neurologic outcome group. However, the platelet counts remained low in the poor outcome group. Low platelet counts on the 7th day were associated with poor neurologic outcomes (aOR 0.975, 95% CI, 0.961-0.989) and mortality at 6 months (aOR 0.986, 95% CI, 0.975-0.997) after adjusting for covariates.

CONCLUSION

The changes in platelet counts in OHCA patients have a biphasic pattern that is significantly different in patients with good neurologic outcomes and those with poor neurologic outcomes at 6 months. A low platelet count 7 days after CA was associated with a poor neurologic outcome and mortality at 6 months.

Bleeding Complications After Cardiac Arrest and Targeted Temperature Management, a Post Hoc Study of the Targeted Temperature Management Trial

Target Temperature Management (TTM) is standard care following out of hospital cardiac arrest (OHCA). The aim of the study was to evaluate if treatment temperature (33°C or 36°C) or other predefined variables were associated with the occurrence of bleeding in the TTM study. This study is a predefined, post hoc analysis of the TTM trial, a multinational randomized controlled trial comparing treatment at 33°C and 36°C for 24 hours after OHCA with return of spontaneous circulation. Bleeding events from several locations were registered daily. The main outcome measure was occurrence of any bleeding during the first 3 days of intensive care. Risk factors for bleeding, including temperature allocation, were evaluated. Complete data were available for 722/939 patients. Temperature allocation was not associated with bleeding either in the univariable (p = 0.95) or in the primary multivariable analysis (odds ratio [OR] 0.95; 95% confidence interval [CI] 0.64-1.41, p = 0.80). A multiple imputation model, including all patients, was used as a sensitivity analysis, rendering similar results (OR 0.98; 95% CI 0.69-1.38, p = 0.92). Factors associated with bleeding were increasing age, female sex, and angiography with percutaneous coronary intervention (PCI) within 36 hours of cardiac arrest (CA) in both the primary and the sensitivity analysis. TTM at 33°C, when compared to TTM at 36°C, was not associated with an increased incidence of bleeding during the first 3 days of intensive care after CA. Increasing age, female gender, and PCI were independently associated with any bleeding the first 3 days after CA.

The opinions of ambulance personnel regarding using a heated mattress for patients being cared for in a cold climate - An intervention study in ambulance care

The purpose of the study was to describe the opinions of ambulance personnel regarding differences between using a heated mattress and a standard ambulance mattress. This study was an intervention study with pre- and post-evaluation. Evaluations of the opinions of personnel regarding the standard unheated mattress were conducted initially. After the intervention with new heated mattresses, follow-up evaluations were conducted. Ambulance personnel (n=64) from an ambulance station in northern Sweden took part in the study, which ran from October 2014 until February 2016. There were differences in opinions regarding the standard unheated mattress and the new heated mattress. The evaluation of the proxy ratings by the personnel showed that the heated mattress was warmer than the standard mattress, more pleasant to lie on and that patients were happier and more relaxed than when the standard mattress was used. The ambulance personnel in this study rated the experience of working with the heated mattress as very positive and proxy rated that it had a good effect on patient comfort. A heated mattress can be recommended for patients in ambulance care, even if more research is needed to receive sufficient evidence.

Coagulofibrinolytic Changes in Patients with Post-cardiac Arrest Syndrome

Whole-body ischemia and reperfusion due to cardiac arrest and subsequent return of spontaneous circulation constitute post-cardiac arrest syndrome (PCAS), which consists of four syndromes including systemic ischemia/reperfusion responses and post-cardiac arrest brain injury. The major pathophysiologies underlying systemic ischemia/reperfusion responses are systemic inflammatory response syndrome and increased coagulation, leading to disseminated intravascular coagulation (DIC), which clinically manifests as obstruction of microcirculation and multiple organ dysfunction. In particular, thrombotic occlusion in the brain due to DIC, referred to as the "no-reflow phenomenon," may be deeply involved in post-cardiac arrest brain injury, which is the leading cause of mortality in patients with PCAS. Coagulofibrinolytic changes in patients with PCAS are characterized by tissue factor-dependent coagulation, which is accelerated by impaired anticoagulant mechanisms, including antithrombin, protein C, thrombomodulin, and tissue factor pathway inhibitor. Damage-associated molecular patterns (DAMPs) accelerate not only tissue factor-dependent coagulation but also the factor XII- and factor XI-dependent activation of coagulation. Inflammatory cytokines are also involved in these changes via the expression of tissue factor on endothelial cells and monocytes, the inhibition of anticoagulant systems, and the release of neutrophil elastase from neutrophils activated by inflammatory cytokines. Hyperfibrinolysis in the early phase of PCAS is followed by inadequate endogenous fibrinolysis and fibrinolytic shutdown by plasminogen activator inhibitor-1. Moreover, cell-free DNA, which is also a DAMP, plays a pivotal role in the inhibition of fibrinolysis. DIC diagnosis criteria or fibrinolysis markers, including d-dimer and fibrin/fibrinogen degradation products, which are commonly tested in patients and easily accessible, can be used to predict the mortality or neurological outcome of PCAS patients with high accuracy. A number of studies have explored therapy for this unique pathophysiology since the first report on "no-reflow phenomenon" was published roughly 50 years ago. However, the optimum therapeutic strategy focusing on the coagulofibrinolytic changes in cardiac arrest or PCAS patients has not yet been established. The elucidation of more precise pathomechanisms of coagulofibrinolytic changes in PCAS may aid in the development of novel therapeutic targets, leading to an improvement in the outcomes of PCAS patients.

Adaptation of global hemostasis to therapeutic hypothermia in patients with out-of-hospital cardiac arrest: Thromboelastography study

BACKGROUND

The use of mild therapeutic hypothermia (MTH) in patients after out-of-hospital cardiac arrest (OHCA) who are undergoing primary percutaneous coronary intervention (pPCI) can protect patients from thromboembolic complications. The aim of the study was to evaluate the adaptive mecha- nisms of the coagulation system in MTH-treated comatose OHCA survivors.

METHODS

Twenty one comatose OHCA survivors with acute coronary syndrome undergoing imme- diate pPCI were treated with MTH. Quantitative and qualitative analyses of physical clot properties were performed using thromboelastography (TEG). Two analysis time points were proposed: 1) during MTH with in vitro rewarming conditions (37°C) and 2) after restoration of normothermia (NT) under normal (37°C) and in vitro cooling conditions (32°C).

RESULTS

During MTH compared to NT, reaction time (R) was lengthened, clot kinetic parameter (a) was significantly reduced, but no effect on clot strength (MA) was observed. Finally, the coagulation index (CI) was significantly reduced with clot fibrinolysis attenuated during MTH. The clot lysis time (CLT) was shortened, and clot stability (LY60) was lower compared with those values during NT. In vitro cooling generally influenced clot kinetics and reduced clot stability after treatment.

CONCLUSIONS

Thromboelastography is a useful method for evaluation of coagulation system dysfunc- tion in OHCA survivors undergoing MTH. Coagulation impairment in hypothermia was associated with a reduced rate of clot formation, increased weakness of clot strength, and disturbances of fibrinoly- sis. Blood sample analyses performed at 32°C during MTH, instead of the standard 37°C, seems to enhance the accuracy of the evaluation of coagulation impairment in hypothermia.

Prolonged targeted temperature management compromises thrombin generation: A randomised clinical trial

AIM

To investigate whether prolonged compared with standard duration of targeted temperature management (TTM) compromises coagulation.

METHODS

Comatose survivors after out-of-hospital cardiac arrest (n=82) were randomised to standard (24h) or prolonged (48h) duration of TTM at 33±1°C. Blood samples were drawn 22, 46 and 70h after attaining the target temperature. Samples were analysed for rotational thromboelastometry (ROTEM^® (EXTEM^®, INTEM^®, FIBTEM^® and HEPTEM^®)) and thrombin generation using the Calibrated Automated Thrombogram^® assay.

RESULTS

With the 22-h sample, we revealed no difference between groups in the ROTEM^® and thrombin generation results beside a slightly higher EXTEM^® and INTEM^® maximum velocity in the prolonged group (p-values≤0.04). With the 46-h sample, ROTEM^® showed no differences when using EXTEM^®; however, 11% (p<0.01) longer clotting time and 12% (p<0.01) longer time to maximum velocity were evident in the prolonged group than in the standard group when using INTEM^®. The prolonged group had reduced thrombin generation compared with the standard group as indicated by 30% longer lag time (p=0.04), 106nM decreased peak concentration (p<0.001), 36% longer time to peak (p=0.01) and 411 nM*minute decreased endogenous thrombin potential (p<0.001). With the 70-h sample, no differences in ROTEM^® results were found between groups. However, the prolonged group had reduced thrombin generation indicated by longer lag time, decreased peak concentration and longer time to peak (all p-values≤0.02) compared with the standard group.

CONCLUSION

Prolonged TTM in post-cardiac arrest patients impairs thrombin generation. ClinicalTrials.gov identifier: NCT02258360.

Effect of ultrasonography and fluoroscopic guidance on the incidence of complications of cannulation in extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a retrospective observational study

BACKGROUND

It remains unclear which cannulation method is best in cases of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest. We assessed the effect of ultrasound- and fluoroscopy-guided percutaneous cannulation on complication incidence, compared with that using only ultrasound guidance.

METHODS

This single-center retrospective observational study was conducted between February 2011 and December 2015. In the comparison group, cannulation was performed percutaneously using only ultrasound guidance. In the exposure group, cannulation was performed percutaneously using fluoroscopy and ultrasound guidance. The primary outcome assessed was whether complications were associated with cannulation. The secondary outcome assessed was the duration from hospital arrival to extracorporeal circulation start. In addition to univariate analysis, multivariate logistic-regression analysis for cannulation complications was performed to adjust for several presumed confounders.

RESULTS

Of the patients who underwent ECPR, 73 were eligible; the comparison group included 50 cases and the exposure group included 23 cases. Univariate analysis showed that the complication incidence of the exposure group was significantly lower than that of the comparison group (8.7 vs. 36.0%, p = 0.022). Duration from hospital arrival to extracorporeal circulation start was almost the same in both groups (median, 17.0 min vs. 17.0 min, p = 0.92). After multivariate logistic regression analysis, cannulation using fluoroscopy and ultrasound was independently associated with a lower complication incidence (adjusted odds ratio, 0.14; p = 0.024).

CONCLUSIONS

Ultrasound- and fluoroscopy-guided cannulation may reduce the complication incidence of cannulation without delaying extracorporeal circulation start.

Exam 4 Questions

A 73-year-old male with a history of hypertension and hyperlipidemia is currently in the stroke unit after suffering a right middle cerebral artery infarct. His symptoms started 2 h prior to arrival at the hospital, and tPA was administered. The patient is plegic on the left side and with mild dysarthria, but is otherwise neurologically intact. His labwork is within normal limits. Which of the following describes the optimal deep venous thrombosis (DVT) prophylaxis regimen for this patient?A.

Wait 6 h post tPA, then administer unfractionated heparin (UFH) along with intermittent pneumatic compression (IPC)

B.

Wait 24 h post tPA, then administer UFH along with IPC

C.

Wait 6 h post tPA, then administer low molecular weight heparin (LMWH) along with IPC

D.

Wait 24 h post tPA, then administer LMWH along with IPC

E.

IPC only for the first 72 h, then LMWH or UFH after obtaining follow-up imaging

All of the following causes of acute encephalitis have the matching characteristic radiological features except:A.

Autoimmune limbic encephalitis: T2/FLAIR hyperintensity in the mesial temporal lobes

B.

Cytomegalovirus: T2/FLAIR hyperintensity in the subependymal white matter

C.

JC virus: T2/FLAIR hyperintensity in the parieto-occipital lobes and corpus callosum

D.

Herpes simplex virus type 1: restricted diffusion in frontal/temporal lobes and insular cortex

E.

Varicella zoster: T2/FLAIR hyperintensity in the brainstem

Which of the following categorizations is most accurate regarding acute respiratory distress syndrome (ARDS) in the setting of subarachnoid hemorrhage (SAH)?A.

Non-neurogenic, non-cardiogenic

B.

Neurogenic, non-cardiogenic

C.

Neurogenic, cardiogenic

D.

Non-neurogenic, cardiogenic

E.

None of the above accurately reflect ARDS in SAH

A 52-year-old female is admitted to the ICU with a Hunt-Hess 1, modified Fisher 2 subarachnoid hemorrhage. Her past medical history is significant for hypertension, diabetes mellitus, and chronic renal insufficiency. She undergoes craniotomy for surgical clipping of an anterior cerebral artery aneurysm, and does not experience any additional complications. Two weeks later, she begins complaining of left calf pain, and a lower extremity sonogram demonstrated a proximal deep venous thrombosis (DVT). The patient weighs 60 kg. Her laboratory values are as follows: sodium 142 mEq/L, potassium 3.4 mEq/L, carbon dioxide 18 mEq/L, blood urea nitrogen (BUN) 70 mg/dL, and serum creatinine 2.5 mg/dL. What would be the optimal treatment for this patient’s proximal DVT?A.

Unfractionated heparin infusion for at least 5 days concomitantly with warfarin therapy

B.

Low molecular weight heparin 60 mg twice a day for at least 5 days concomitantly with warfarin therapy

C.

Fondaparinux 7.5 mg daily for 5 days followed by warfarin therapy

D.

Apixaban 10 mg twice daily for 7 days followed by 5 mg twice daily

E.

Rivaroxaban 15 mg twice daily for 21 days followed by 20 mg once daily

All of the following are currently implicated in uremic encephalopathy except:A.

Derangements in cerebral metabolism

B.

Alterations in the blood-brain barrier

C.

Accumulation of circulating toxins

D.

Imbalance of endogenous neurotransmitters

E.

Recurrent lobar hemorrhages

A 70-year-old female is hospitalized with a recent ischemic infarct. As part of stroke core measures, you obtain a hemoglobin A1c of 10.0. What is an approximate estimation of this patient’s average blood glucose level over the last several months?A.

70 mg/dL

B.

100 mg/dL

C.

130 mg/dL

D.

190 mg/dL

E.

240 mg/dL

A 28-year-old female with no known past medical history is in the ICU in status epilepticus, with anti-N-methyl D-aspartate (NMDA) receptor antibodies isolated in the cerebrospinal fluid. Which of the following is most likely to identify the root cause of her illness?A.

Transvaginal ultrasound

B.

Contrast-enhanced CT of the chest

C.

Contrast-enhanced CT of the brain

D.

Virtual colonography

E.

Thorough examination of the skin, particularly in sun-exposed areas

A 17-year-old male with no significant past medical history collapses during a high school football game, and goes into cardiac arrest. He did not have any complaints earlier in the day. The patient is brought to a nearby hospital, where is he resuscitated, intubated, and transferred to the ICU for further management. The patient is currently undergoing therapeutic hypothermia, and a work-up is underway to determine the cause of his sudden collapse. Which of the following is the most likely diagnosis?A.

Rupture of a previously undiagnosed cerebral aneurysm

B.

Hypertrophic cardiomyopathy

C.

Commotio cordis

D.

Severe hyponatremia and cerebral edema

E.

Brugada syndrome

A 31-year-old female at 38 weeks gestation is currently hospitalized for the treatment of preeclampsia. Due to her medical condition, her obstetrician is currently considering induced labor. At which point will this patient no longer be at risk for developing frank seizure activity as a result of her condition?A.

48 h postpartum

B.

1 week after delivery

C.

2 weeks after delivery

D.

4 weeks after delivery

E.

6 weeks after delivery

A 38-year-old male with no prior medical history presents to the emergency department with fever and severe headaches for several days. A CT scan of the brain is unremarkable, and the results of a lumbar puncture are pending. What is the most appropriate empiric antimicrobial regimen at this time?A.

Cefazolin and vancomycin

B.

Ceftriaxone and vancomycin

C.

Ceftriaxone, vancomycin and ampicillin

D.

Piperacillin/tazobactam and vancomycin

E.

Meropenem and vancomycin

The majority of intramedullary spinal cord neoplasms are:A.

Astrocytomas

B.

Meningiomas

C.

Metastatic lesions

D.

Ependymomas

E.

Hemangioblastomas

Which of the following derived parameter formulas is correct?A.

Cardiac index = cardiac output x body surface area

B.

Stroke volume = cardiac output/heart rate

C.

Systemic vascular resistance = 80 × (mean arterial pressure/cardiac output)

D.

Pulmonary vascular resistance = 80 × (mean pulmonary artery pressure/cardiac output)

E.

All of the above are correct

A 23-year-old female marathon runner is currently in the ICU after suffering from heat stroke following an outdoor run on a particularly hot summer day. She was initially delirious in the emergency department, but progressed to coma and respiratory failure requiring mechanical ventilation. Her oral temperature is 42.1 °C. Which of the following would be most effective in reducing this patient’s severe hyperthermia?A.

Regularly scheduled alternating acetaminophen and ibuprofen

B.

Spraying room temperature water on the patient, followed by fanning

C.

Ice water immersion

D.

Dantrolene sodium, 2.5 mg/kg

E.

Application of ice packs to the groin and axilla

Hyperinsulinemia-euglycemia (HIE) therapy may be useful for toxicity related to which of the following?A.

Tricyclic antidepressants

B.

Calcium channel blockers

C.

Aspirin

D.

Digoxin

E.

Lithium

A 71-year-old female with a history of alcohol abuse is currently intubated in the ICU following a catastrophic spontaneous left basal ganglia hemorrhage with resultant herniation. You have just declared her brain dead. The patient’s family agrees to make her an organ donor, and the organ donation coordinator requests you initiate levothyroxine therapy. Which of the following benefits would be expected with this treatment?A.

Increase the number of solid organs available for transplant

B.

Eliminate the need for hepatic biopsy prior to liver transplant

C.

Eliminate the need for cardiac catheterization prior to heart transplant

D.

Eliminate the need for bronchoscopy prior to lung transplant

E.

Reduce the need for supplementation of sodium, potassium, calcium, and magnesium

Which of the following is not an element of the Full Outline of Unresponsiveness (FOUR) score?A.

Eye opening

B.

Respiratory function

C.

Brainstem reflexes

D.

Motor response

E.

Verbal response

A 23-year-old female is currently in the ICU with status asthmaticus. She was initially on noninvasive positive pressure ventilation, with an arterial blood gas (ABG) as follows: pH 7.13, pCO₂ 60 mmHg, PaO₂ is 61 mmHg, HCO₃ 24 mmol/L, and oxygen saturation of 90%. She is given continuous inhaled albuterol, intravenous steroids, and magnesium sulfate. She subsequently becomes more lethargic and is intubated, with settings as follows: volume assist-control, rate of 12 breaths/min, tidal volume of 500 cc, PEEP of 5 cm H₂O, and FiO₂ of 50%. Peak airway pressure is 50 cm H₂O and plateau pressure is 15 cm H₂O. A stat portable chest x-ray shows hyperinflation with no pneumothorax. A repeat ABG after 30 min of invasive ventilation shows the following: pH of 7.24, pCO₂ 49 mmHg, PaO₂ 71 mmHg, HCO₃ is 25 mmol/L. Which of the following should be performed next?A.

Increase rate to 16

B.

Increase tidal volume to 600 cc

C.

Initiate bicarbonate infusion

D.

Switch to pressure assist-control

E.

Maintain current settings

Which of the following mechanisms is implicated in super-refractory status epilepticus?A.

Influx of proinflammatory molecules

B.

Upregulation of NMDA receptors

C.

Upregulation of molecular transport molecules

D.

Downregulation of GABA receptors

E.

All of the above

A 85-year-old male with a history nephrolithiasis, mild dementia, and alcohol abuse presented to the emergency department after a fall from standing, and was found to a right holohemispheric subdural hematoma. His clot was evacuated successfully, in spite of his oozing diathesis in the operating room (INR on arrival was 1.4 with a platelet count of 88 × 10³/μL). His serum transaminases are twice the normal value, and he has had refractory chronic hyponatremia. He has had three convulsions during this week of hospitalization, in spite of levetiracetam therapy at 1.5 g twice a day. Over the past 24 h, he has had a marked increase in agitation. He has also just had a 5-s run of non-sustained ventricular tachycardia, and his systolic blood pressure is now 85 mmHg. You are considering discontinuing his levetiracetam and starting a new agent. Which of the following would be the best choice in this scenario?A.

Carbamazepine

B.

Phenytoin

C.

Valproate

D.

Lacosamide

E.

Topiramate

A 65-year-old male with a history of COPD on rescue albuterol and ipratropium is diagnosed with myasthenia gravis, and started on an acetylcholinesterase inhibitor. He returns several days later complaining of increased salivation and worsening bronchial secretions in the absence of fevers, purulent sputum, or increasing dyspnea. These symptoms are not relieved by use of his albuterol. On exam, he has slightly decreased air movement throughout both lung fields without any clear wheezing, no focal rales, and a normal inspiratory to expiratory ratio. Which treatment option is most likely to be beneficial?A.

Increase frequency of short-acting ß₂ agonist use

B.

Add a standing long-acting inhaled ß₂ agonist

C.

Add glycopyrrolate as needed

D.

Add inhaled corticosteroids

E.

Add oral systemic corticosteroids

Regarding states of impaired consciousness, which of the following statements regarding arousal and awareness is correct?A.

Coma: intact arousal, but impaired awareness

B.

Minimally conscious state: impaired arousal and impaired awareness

C.

Persistent vegetative state: intact arousal, but impaired awareness

D.

Locked-in state: intact arousal, but impaired awareness

E.

All of the above are correct

A 62-year-old female is currently in the ICU following craniotomy for clipping of a cerebral aneurysm. Postoperatively, she is noted to have an oxygen saturation of 92% on 50% non-rebreather face mask, and her respiratory rate is 32 breaths/min. She denies chest pain. Her blood pressure is 96/72 mmHg and heart rate is 120 beats/min. Nimodipine has been held according to blood pressure parameters. A portable chest x-ray shows hazy opacities bilaterally, and bedside echocardiogram shows decreased left ventricular systolic function with apical, septal, lateral, anterior, anteroseptal and inferolateral wall akinesis, along with apical ballooning. Which of the following should be performed next?A.

Intubate the patient and begin mechanical ventilation

B.

Call urgent cardiology consult for cardiac catheterization

C.

Start noninvasive positive airway pressure ventilation

D.

Administer broad spectrum antibiotics

E.

Administer albuterol and systemic corticosteroids

Which of the following is the most common etiology of acute spinal cord ischemia and infarction?A.

Atherosclerotic disease

B.

Rupture of an abdominal aortic aneurysm

C.

Degenerative spine disease

D.

Cardioembolic events

E.

Systemic hypotension in the setting of other disease processes

A 62-year-old female with a history of coronary artery disease has just been admitted to the ICU with a left-sided spontaneous basal ganglia hemorrhage. The patient takes 325 mg of aspirin daily at home, and you are considering platelet transfusion. Which of the following has been demonstrated regarding platelet transfusion in this setting?A.

Improved chances of survival to hospital discharge

B.

Decreased hospital length-of-stay

C.

Improved chances of survival at 3 months

D.

Improved modified Rankin scale at 3 months

E.

None of the above

Which of the following therapies has been shown to decrease the incidence of delayed cerebral ischemia (DCI) in the setting of subarachnoid hemorrhage (SAH)?A.

Atorvastatin

B.

Magnesium

C.

Methylprednisolone

D.

Nicardipine

E.

None of the above

A 70-year-old male with a history of diabetes, hypertension, and cigarette smoking (one pack per day for the last 40 years) is currently in the ICU with a COPD exacerbation. This is his third exacerbation this year, and was discharged from the hospital only 3 weeks prior. On your examination, he is alert, his breathing is labored, and he has rales at the right lung base. His vital signs are as follows: blood pressure 90/60 mmHg, heart rate 120 beats per minute, respirations 28 per minute, and temperature 38.3 °C. His oxygen saturation on 50% face mask is 93%, and his most recent PCO₂ is 55 mmHg. Labs are notable for the following: white blood cell count 14.4 × 10⁹/L with 90% neutrophils, blood urea nitrogen (BUN) 30 mg/dL, serum creatinine 1.2 mg/dL, and glucose 240 mg/dL. Ketones are negative. He is currently on noninvasive positive pressure ventilation at 10/5 cm H₂O and 50% FiO₂, and broad spectrum antibiotics have been administered. An hour later, the nurse pages you because his heart rate is now 140 beats per minute and irregular, blood pressure is 85 systolic, oxygen saturation is 85%, and he is minimally responsive. You now hear bilateral rales, most prominently in the right lung base, and scattered wheezes. Which of the following should be performed next?A.

Increase inspiratory pressure to 15 and FiO₂ to 100%

B.

Start a continuous diltiazem infusion and give intravenous furosemide

C.

Start a continuous phenylephrine infusion targeting a mean arterial pressure (MAP) > 65

D.

Give 125 mg of solumedrol and administer albuterol via nebulizer

E.

Intubate the patient and initiate mechanical ventilation

A 57-year-old male with a history of epilepsy is currently in the stroke unit following a large right middle cerebral artery infarction. A nasogastric tube has been inserted, and 24 h continuous enteral feeds have been initiated. The patient is currently on 100 mg of phenytoin every 8 h for seizure prophylaxis. Which of the following measures should be taken to prevent the patient from developing subtherapeutic phenytoin levels?A.

Change to 18 h tube feeds, and only administer phenytoin at night

B.

Change to 18 h tube feeds, and only administer phenytoin twice daily

C.

Switch from standard to hydrolyzed tube feeds

D.

Switch from standard to glycemic control tube feeds

E.

Hold tube feeds for 2 h before and after phenytoin administration

A 37-year-old female presents to the emergency department with approximately 2 weeks of progressively worsening clumsiness and drastic mood swings. Her past medical history is significant only for Crohn’s disease, for which she takes both natalizumab and infliximab. A contrast-enhanced CT scan of her head is performed, revealing hypodense, non-enhancing lesions in the cortical white matter of the frontal and parietal lobes. Despite treatment, the patient expires 1 month later. Which of the following is true regarding the most likely diagnosis?A.

The diagnosis may be confirmed via CSF analysis

B.

The pathologic process spares oligodendrocytes

C.

It is a prion-based disease

D.

The condition is universally fatal despite treatment

E.

All of the above

A 58-year-old female presents to the emergency department with dry cough, fever and rapidly progressive dyspnea over 1 week. She has a history of rheumatoid arthritis (RA) and is maintained on weekly methotrexate and daily prednisone (which was increased to 30 mg starting 1 month ago for an acute flare). She takes no other medications. Her vital signs are as follows: blood pressure 100/70 mmHg, heart rate 110 beats/min, respiratory rate 20 breaths/min, and temperature 38.0 °C. In the ED she develops progressive hypoxemia with oxygen saturation 92% on 100% nonrebreather, and is increasingly diaphoretic. She is emergently intubated, and a chest x-ray post intubation shows extensive bilateral lung opacities. Which of the following should be administered at this time?A.

Ceftriaxone and azithromycin

B.

Vancomycin and piperacillin-tazobactam

C.

Vancomycin, cefepime, and fluconzole

D.

Ceftriaxone, levofloxacin, and trimethoprim-sulfamethoxazole

E.

Tigecycline only

A 45-year-old woman undergoes uncomplicated transsphenoidal resection of a pituitary macroadenoma. She appears well hydrated and is not complaining of excessive thirst. Post-operatively, she is noted to have increased urine output. Serum sodium is 137 mEq/L, and serum osmolarity is 275 mOsm/kg. What is the most likely cause of her polyuria?A.

Syndrome of inappropriate antidiuretic hormone

B.

Diabetes insipidus

C.

Cerebral salt wasting

D.

Fluid mobilization

E.

All of the above are equally likely

A 36-year-old female with a recent lumbar puncture to rule out subarachnoid hemorrhage is now complaining of a severe headache unlike anything she has experienced previously. She reports her headache is worse when standing, and better upon lying flat. She is otherwise neurologically intact. All of the following medications may be beneficial in this scenario except:A.

Acetaminophen

B.

Ibuprofen

C.

Caffeine

D.

Aminophylline

E.

Methylprednisolone

Which of the following is the most common overall cause of acute myocardial infarction?A.

Coronary dissection

B.

Plaque rupture

C.

Imbalance between oxygen demand and supply across a fixed obstruction

D.

Coronary vasospasm

E.

Ischemia related to hypotension and decreased perfusion

A 78-year-old male is in the ICU recovering from sepsis and pneumonia. He was just recently extubated after 2 days of mechanical ventilation and sedation with a fentanyl infusion. Over the ensuing days, he develops worsening abdominal distention, poor bowel sounds, and no stool output. CT scan reveals significant colonic distention, but no mass or obstruction. Records demonstrate a normal routine colonoscopy performed 6 weeks ago. You have appropriately hydrated the patient, corrected any electrolyte abnormalities, placed a rectal tube, withheld all opiates, and given intravenous erythromycin, but to no avail. Abdominal x-rays continue to demonstrate marked cecal dilatation greater than 12 cm in diameter. What is the next best appropriate therapy for this patient?A.

Neostigmine

B.

Naloxone

C.

Metoclopromide

D.

Surgical consultation for hemicolectomy

E.

Endoscopic percutaneous cecostomy tube placement

Which of the following is the most common cerebral vascular malformation in the general population?A.

AV malformation

B.

Dural AV fistula

C.

Developmental venous anomaly

D.

Cavernous malformation

E.

Vein of Galen malformation

A 49-year-old female with a history of acute lymphoblastic leukemia and recent subcutaneous cerebrospinal fluid (CSF) reservoir placement presents to the emergency department with fever, chills, and increased confusion for the past 3 days. Her CSF reservoir was last accessed 1 week ago. A thorough work-up reveals no other obvious infectious source, and there is concern for CSF reservoir-associated meningitis. Which of the following is the most likely causative organism?A.

Coagulase-negative staphylococci

B.

Propionobacterium acnes

C.

Methicillin-resistant Staphylococcus aureus

D.

Klebsiella pneumoniae

E.

Neisseria meningitidis

A 47-year-old woman presents to the emergency department with headache, nausea, and vomiting. Non-contrast head CT is performed, revealing subarachnoid blood in the right Sylvian fissure, and conventional angiography reveals the presents of a large right-sided MCA aneurysm. The patient undergoes successful surgical clipping of her aneurysm, and is being observed in the ICU. On admission, the patient’s serum sodium was 142 mEq/L and the hematocrit was 37%; by the seventh post-operative day, the serum sodium is 127 mEq/L and the hematocrit is 44%. Bedside ultrasonography demonstrates an IVC diameter of approximately 0.9 cm. Which of the following interventions would be least reasonable at this time?A.

Fludrocortisone, 0.2 mg twice a day

B.

2% hypertonic saline, infused peripherally

C.

3% hypertonic saline, infused centrally

D.

Sodium chloride oral tablets

E.

1500 mL daily fluid restriction

Which of the following is true regarding central (non-infectious) fever?A.

Less common in subarachnoid hemorrhage

B.

More common versus infectious fever

C.

Earlier onset versus infectious fever

D.

Easier to confirm versus infectious fever

E.

All of the above

Flaccid paralysis is most commonly associated with which of the following forms of encephalitis?A.

West Nile

B.

Varicella zoster

C.

Rabies

D.

Herpes simplex

E.

Epstein-Barr

Which of the following would not be considered appropriate therapy for heparin-induced thrombocytopenia (HIT)?A.

Discontinuation of heparin products alone

B.

Danaparoid

C.

Fondaparinux

D.

Argatroban

E.

All of the above are acceptable treatment options

A 45-year-old male with severe blunt traumatic brain injury (TBI) from a motor vehicle collision suffered a ventricular fibrillation cardiac arrest at the time of injury with return of spontaneous circulation (ROSC) in the field after endotracheal intubation and one dose of epinephrine. On arrival to the emergency department, no regional wall motion abnormalities were noted on surface echocardiography and no ST segment changes were seen on the presenting EKG. Head CT revealed cerebral contusions but no extra-axial mass lesions. The patient is now in the ICU and found to be comatose without sedation. Mild therapeutic hypothermia to 33° is being considered in the management of this post-arrest patient. Which of the following statements is true?A.

Mild therapeutic hypothermia is contraindicated due to the risk of induced epilepsy

B.

Mild therapeutic hypothermia is contraindicated with any intracranial pathology on CT imaging

C.

Mild therapeutic hypothermia does not induce a clinically significant coagulopathy

D.

Patients who have sustained ROSC after an arrest associated with TBI do not benefit from therapeutic hypothermia

E.

Endovascular cooling is superior to surface cooling in young patients with ROSC

A 35-year-old male is in the intensive care unit following resection of a large right-sided meningioma. He is currently intubated and sedated on a continuous fentanyl infusion. The nurse calls you to the bedside due to concerns over “unusual ventilator waveforms”. Upon arrival, you note the following (see Image 1). What is the best way to describe this phenomenon?A.

Reverse triggering

B.

Double triggering

C.

Breath stacking

D.

Missed triggering

E.

None of the above; normal ventilator waveforms are present