Romergryko G. Geocadin

Part 9: Post–Cardiac Arrest Care 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

The goal of immediate post-cardiac arrest care is to optimize systemic perfusion, restore metabolic homeostasis, and support organ system function to increase the likelihood of intact neurological survival. The post-cardiac arrest period is often marked by hemodynamic instability as well as metabolic abnormalities. Support and treatment of acute myocardial dysfunction and acute myocardial ischemia can increase the probability of survival. Interventions to reduce secondary brain injury, such as therapeutic hypothermia, can improve survival and neurological recovery. Every organ system is at risk during this period, and patients are at risk of developing multiorgan dysfunction. The comprehensive treatment of diverse problems after cardiac arrest involves multidisciplinary aspects of critical care, cardiology, and neurology. For this reason, it is important to admit patients to appropriate critical-care units with a prospective plan of care to anticipate, monitor, and treat each of these diverse problems. It is also important to appreciate the relative strengths and weaknesses of different tools for estimating the prognosis of patients after cardiac arrest.

Part 8: Post-cardiac arrest care: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care

The recommendations in this 2015 American Heart Association (AHA) Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care are based on an extensive evidence review process that was begun by the International Liaison Committee on Resuscitation (ILCOR) after the publication of the 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations 1,2 and was completed in February 2015.3,4 In this in-depth evidence review process, ILCOR examined topics and then generated a prioritized list of questions for systematic review. Questions were first formulated in PICO (population, intervention, comparator, outcome) format,5 and then search strategies and inclusion and exclusion criteria were defined and a search for relevant articles was performed. The evidence was evaluated by the ILCOR task forces by using the standardized methodological approach proposed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group.6 The quality of the evidence was categorized based on the study methodologies and the 5 core GRADE domains of risk of bias, inconsistency, indirectness, imprecision, and other considerations (including publication bias). Then, where possible, consensus-based treatment recommendations were created. To create this 2015 Guidelines Update, the AHA formed 15 writing groups, with careful attention to manage conflicts of interest, to assess the ILCOR treatment recommendations and to write AHA treatment recommendations by using the AHA Class of Recommendation (COR) and Level of Evidence (LOE) system. The recommendations made in the Guidelines are informed by the ILCOR recommendations and GRADE classification, in the context of the delivery of medical care in North America. The AHA writing group made new recommendations only on topics specifically reviewed by ILCOR in 2015. This chapter delineates instances where the AHA writing group developed recommendations that are significantly stronger or weaker than the ILCOR statements. In the online …

Reversal of transtentorial herniation with hypertonic saline

Objective: To evaluate the role of 23.4% saline in the management of transtentorial herniation (TTH) in patients with supratentorial lesions. Methods: Consecutive patients with clinically defined TTH treated with 23.4% saline (30 to 60 mL) were included in a retrospective cohort. Factors associated with successful reversal of TTH were determined. Results: Seventy-six TTH events occurred in 68 patients admitted with intracerebral hemorrhage (n = 29), subarachnoid hemorrhage (n = 16), stroke (n = 8), brain tumor (n = 8), subdural hematoma (n = 5), epidural hematoma (n = 1), and meningitis (n = 1). In addition to 23.4% saline, TTH management included hyperventilation (70% of events), mannitol (57%), propofol (62%), pentobarbital (15%), ventriculostomy drainage (27%), and decompressive hemicraniectomy (18%). Reversal of TTH occurred in 57/76 events (75%). Intracranial pressure decreased from 23 ± 16 mm Hg at the time of TTH to 14 ± 10 mm Hg at 1 hour (p = 0.002), and 11 ± 12 mm Hg at 24 hours (p = 0.001) among 22 patients with intracranial pressure monitors. Reversal of TTH was predicted by a ≥5 mmol/L rise in serum sodium concentration (p = 0.001) or an absolute serum sodium of ≥145 mmol/L (p = 0.007) 1 hour after 23.4% saline. Adverse effects included transient hypotension in 13 events (17%); no evidence of central pontine myelinolysis was detected on post-herniation MRI (n = 18). Twenty-two patients (32%) survived to discharge, with severe disability in 17 and mild to moderate disability in 5. Conclusion: Treatment with 23.4% saline was associated with rapid reversal of transtentorial herniation (TTH) and reduced intracranial pressure, and had few adverse effects. Outcomes of TTH were poor, but medical reversal may extend the window for adjunctive treatments.

Primary Outcomes for Resuscitation Science Studies A Consensus Statement From the American Heart Association

Background and Purpose— The guidelines presented in this consensus statement are intended to serve researchers, clinicians, reviewers, and regulators in the selection of the most appropriate primary outcome for a clinical trial of cardiac arrest therapies. The American Heart Association guidelines for the treatment of cardiac arrest depend on high-quality clinical trials, which depend on the selection of a meaningful primary outcome. Because this selection process has been the subject of much controversy, a consensus conference was convened with national and international experts, the National Institutes of Health, and the US Food and Drug Administration. Methods— The Research Working Group of the American Heart Association Emergency Cardiovascular Care Committee nominated subject leaders, conference attendees, and writing group members on the basis of their expertise in clinical trials and a diverse perspective of cardiovascular and neurological outcomes (see the online-only Data Supplement). Approval was obtained from the Emergency Cardiovascular Care Committee and the American Heart Association Manuscript Oversight Committee. Preconference position papers were circulated for review; the conference was held; and postconference consensus documents were circulated for review and comments were invited from experts, conference attendees, and writing group members. Discussions focused on (1) when after cardiac arrest the measurement time point should occur; (2) what cardiovascular, neurological, and other physiology should be assessed; and (3) the costs associated with various end points. The final document underwent extensive revision and peer review by the Emergency Cardiovascular Care Committee, the American Heart Association Science Advisory and Coordinating Committee, and oversight committees. Results— There was consensus that no single primary outcome is appropriate for all studies of cardiac arrest. The best outcome measure is the pairing of a time point and physiological condition that will best answer the question under study. Conference participants were asked to assign an outcome to each of 4 hypothetical cases; however, there was not complete agreement on an ideal outcome measure even after extensive discussion and debate. There was general consensus that it is appropriate for earlier studies to enroll fewer patients and to use earlier time points such as return of spontaneous circulation, simple “alive versus dead,” hospital mortality, or a hemodynamic parameter. For larger studies, a longer time point after arrest should be considered because neurological assessments fluctuate for at least 90 days after arrest. For large trials designed to have a major impact on public health policy, longer-term end points such as 90 days coupled with neurocognitive and quality-of-life assessments should be considered, as should the additional costs of this approach. For studies that will require regulatory oversight, early discussions with regulatory agencies are strongly advised. For neurological assessment of post–cardiac arrest patients, researchers may wish to use the Cerebral Performance Categories or modified Rankin Scale for global outcomes. Conclusions— Although there is no single recommended outcome measure for trials of cardiac arrest care, the simple Cerebral Performance Categories or modified Rankin Scale after 90 days provides a reasonable outcome parameter for many trials. The lack of an easy-to-administer neurological functional outcome measure that is well validated in post–cardiac arrest patients is a major limitation to the field and should be a high priority for future development.

A novel quantitative EEG injury measure of global cerebral ischemia

OBJECTIVE To develop a novel quantitative EEG (qEEG) based analysis method, cepstral distance (CD) and compare it to spectral distance (SD) in detecting EEG changes related to global ischemia in rats. METHODS Adult Wistar rats were subjected to asphyxic-cardiac arrest for sham, 1, 3, 5 and 7 min (n=5 per group). The EEG signal was processed and fitted into an autoregressive (AR) model. A pre-injury baseline EEG was compared to selected data segments during asphyxia and recovery. The dissimilarities in the EEG segments were measured using CD and SD. A segment measured was considered abnormal when it exceeded 30% of baseline and its duration was used as the index of injury. A comprehensive Neurodeficit Score (NDS) at 24 h was used to assess outcome and was correlated with CD and SD measures. RESULTS A higher correlation was found with CD and asphyxia time (r=0.81, P<0.001) compared to SD and asphyxia time (r=0.69, P<0.001). Correlation with cardiac arrest time (MAP<10 mmHg) showed that CD was superior (r=0.71, P<0.001) to SD (r=0.52, P=0.002). CD obtained during global ischemia and 90 min into recovery correlated significantly with NDS at 24 h after injury (Spearman coefficient=-0.83, P<0.005), and was more robust than the traditional SD (Spearman coefficient=-0.63, P<0.005). CONCLUSION The novel qEEG-based injury index from CD was superior to SD in quantifying early cerebral dysfunction after cardiac arrest and in providing neurological prognosis at 24 h after global ischemia in adult rats. Studying early qEEG changes after asphyxic-cardiac arrest may provide new insights into the injury and recovery process, and present opportunities for therapy.

Risk factors for multiple intracranial aneurysms

OBJECTIVE Risk factors that predispose to the formation of multiple intracranial aneurysms, which are present in up to 34% of patients with intracranial aneurysms, are not well defined. In this study, we examined the association between known risk factors for cerebrovascular disease and presence of multiple intracranial aneurysms. METHODS We reviewed the medical records and results of conventional angiography in all patients with a diagnosis of intracranial aneurysms admitted to the Johns Hopkins University hospital between January 1990 and June 1997. We determined the independent association between various cerebrovascular risk factors and the presence of multiple aneurysms using logistic regression analysis. RESULTS Of 419 patients admitted with intracranial aneurysms (298 ruptured and 121 unruptured), 127 (30%) had multiple intracranial aneurysms. In univariate analysis, female gender (odds ratio [OR] = 1.9; 95% confidence interval [CI], 1.1-3.3) and cigarette smoking at any time (OR = 1.8; 95% CI, 1.1-3.0) were significantly associated with presence of multiple aneurysms. In the multivariate analysis, cigarette smoking at any time (OR = 1.7; 95% CI, 1.1-2.8) and female gender (OR = 2.1; 95% CI 1.2-3.5) remained significantly associated with multiple aneurysms. Hypertension, diabetes mellitus, and alcohol and illicit drug use were not significantly associated with presence of multiple aneurysms. CONCLUSION Cigarette smoking and female gender seem to increase the risk for multiple aneurysms in patients predisposed to intracranial aneurysm formation. Further studies are required to investigate the mechanism underlying the association between cigarette smoking and intracranial aneurysm formation.

Neurologic prognosis and withdrawal of life support after resuscitation from cardiac arrest

Objective: To study the impact of neurologic prognostication on the decision to withdraw life-sustaining therapies (LST) in comatose patients resuscitated after cardiac arrest. Methods: The authors prospectively studied a consecutive series of post-resuscitation comatose patients referred for neurologic prognostication at a single center for 4 years. For most patients, neurologic prognostication was not sought due to early death or rapid return to consciousness. Prognostication was based on Glasgow Coma Score (GCS) and Brainstem Reflex Score (BRS), with EEG and cortical evoked potentials (CEP), which were graded as benign, uncertain, and malignant. The outcomes were as follows: survivors (Group S), brain or cardiac death (Group D), and death from withdrawal of life sustaining therapy (Group W). In Group W, the time interval to withdrawal of LST was analyzed by EEG and CEP grades. Results: Of 58 patients studied, 10 were in Group S, 8 in Group D, and 40 in Group W. Initial median GCS and BRS was similar for all groups with significant improvement noted in Group S, but not in Group D or Group W. In Group W, CEP grade correlated with the median duration of continued therapy before a decision to withdraw LST: 7 days for benign CEP, 2 days for uncertain CEP, and 1 day for malignant CEP, p = 0.0004. Conclusion: In patients with poor neurologic recovery early after resuscitation from cardiac arrest, physicians appear to use the cortical evoked potential grade to estimate prognosis. Cortical evoked potential grade correlated with the waiting time until life sustaining therapies were withdrawn after no improvement in neurologic examination was seen.

Long-term outcome after medical reversal of transtentorial herniation in patients with supratentorial mass lesions.

Objective: To determine the short‐ and long‐term outcomes after successful reversal of transtentorial herniation by medical treatment. Although it has been recognized that aggressive medical management can reverse transtentorial herniation, it is believed that overall outcome in such patients is poor. Design: Prospective cohort study. Setting: Neurocritical care unit of a university hospital. Patients: A total of 28 consecutive patients who underwent an episode of transtentorial herniation (defined as decrease in level of consciousness accompanied by pupillary dilation) secondary to a supratentorial mass lesion followed by successful reversal. Intervention: Herniation was reversed by using a combination of hyperventilation, mannitol and hypertonic saline. Measurements and Main Results: The following outcomes were analyzed: risk of second herniation, radiologic evidence of structural damage or vascular compromise related to herniation on post‐herniation computed tomographic scan, in‐hospital mortality, and long‐term functional outcome using Rankin score and Barthel index. A total of 32 episodes of transtentorial herniations were reversed in 28 patients during a 14‐month period. The most common precipitating cause were edema (n = 23) or new/expanding intracerebral hematoma (n = 5). After first reversal of transtentorial herniation in 28 patients, a second herniation episode was observed in 16 patients after a mean interval of 88.2 hrs (range, 23‐432 hrs); four were successfully reversed. On follow‐up computed tomographic scan, hypodense lesion in mid‐brain (n = 6), temporal lobe contusion (n = 2), posterior cerebral artery (n = 3), and middle cerebral artery (n = 1) infarction were visualized in a minority of patients. The in‐hospital mortality was 60% (n = 15) with brain death being the cause of death in 13 patients; care was withdrawn in eight patients. Second episode of herniation (p = .002) and midbrain involvement during herniation (p = .02) were associated with in‐hospital mortality. During a mean follow‐up period of 11.4 ± 4.2 months, two patients died of cerebral neoplasm and human immunodeficiency virus‐related sepsis, respectively. Of the 11 survivors, 7 were functionally independent (Rankin score <3 and Barthel index >60). Conclusions: Although mortality after transtentorial herniation is high, we found a prominent potential for meaningful recovery with aggressive medical reversal of transtentorial herniation. Our study implies that timely medical intervention for reversing transtentorial herniation can result in preservation of neurologic function.

Management of Brain Injury After Resuscitation From Cardiac Arrest

The devastating neurologic injury in survivors of cardiac arrest has been recognized since the development of modern resuscitation techniques. After numerous failed clinical trials, two trials showed that induced mild hypothermia can ameliorate brain injury and improve survival and functional neurologic outcome in comatose survivors of out-of-hospital cardiac arrest. This article provides a comprehensive review of the advances in the care of brain injury after cardiac arrest, with updates on the process of prognostication, the use of therapeutic hypothermia and adjunctive intensive care unit care for cardiac arrest survivors.

Ketogenic diet for adults in super-refractory status epilepticus

Objective: To describe a case series of adult patients in the intensive care unit in super-refractory status epilepticus (SRSE; refractory status lasting 24 hours or more despite appropriate anesthetic treatment) who received treatment with the ketogenic diet (KD). Methods: We performed a retrospective case review at 4 medical centers of adult patients with SRSE treated with the KD. Data collected included demographic features, clinical presentation, diagnosis, EEG data, anticonvulsant treatment, and timing and duration of the KD. Primary outcome measures were resolution of status epilepticus (SE) after initiation of KD and ability to wean from anesthetic agents. Results: Ten adult patients at 4 medical centers were started on the KD for SRSE. The median age was 33 years (interquartile range [IQR] 21), 4 patients (40%) were male, and 7 (70%) had encephalitis. The median duration of SE before initiation of KD was 21.5 days (IQR 28) and the median number of antiepileptic medications used before initiation of KD was 7 (IQR 7). Ninety percent of patients achieved ketosis, and SE ceased in all patients achieving ketosis in a median of 3 days (IQR 8). Three patients had minor complications of the KD including transient acidosis and hypertriglyceridemia and 2 patients ultimately died of causes unrelated to the KD. Conclusion: We describe treatment of critically ill adult patients with SRSE with the KD, with 90% of patients achieving resolution of SE. Prospective trials are warranted to examine the efficacy of the KD in adults with refractory SE. Classification of evidence: This study provides Class IV evidence that for intensive care unit patients with refractory SE, a KD leads to resolution of the SE.