Emergency Neurological Life Support: Pharmacotherapy

Managing Intracranial Pressure Crisis

PURPOSE OF REVIEW

The objective of this review is to provide a comprehensive management protocol for the treatment of intracranial pressure (ICP) crises based on the latest evidence.

RECENT FINDINGS

The review discusses updated information on various aspects of critical care management in patients experiencing ICP crises, including mechanical ventilation, fluid therapy, hemoglobin targets, and hypertonic saline infusion, the advantages of ICP monitoring, the critical ICP threshold, and bedside neuromonitoring. All aspects of critical care treatment, including hemodynamic and respiratory support and adjustment of ICP reduction therapy, may impact patient outcomes. ICP monitoring allows ICP values, trends, waveforms, and CPP calculation, which are helpful to guide patient care. Advanced neuromonitoring devices are available at the bedside to diagnose impaired intracranial compliance and intracranial hypertension, assess brain function, and optimize cerebral perfusion. Future research should focus on developing appropriate intervention protocols for both invasive and noninvasive neuromonitoring in managing ICP crisis patients.

The association between neuromuscular blockade use during target temperature management and neurological outcomes

BACKGROUND

To date, no study has comprehensively analyzed the association between neuromuscular blockade (NMB) during target temperature management (TTM) and the neurological outcomes after out-of-hospital cardiac arrest (OHCA) using a multicenter dataset. We aimed to examine the association between NMB during TTM after cardiac arrest and neurological outcomes after OHCA.

METHODS

This study was a secondary analysis of the Japanese Population-based Utstein-style study with defibrillation and basic/advanced Life Support Education and implementation-Hypothermia (J-PULSE-HYPO) study registry. The exposure of the current study was the use of NMB during TTM. The primary outcome was favorable neurological outcome, i.e., a cerebral performance category of 1-2, at hospital discharge.

RESULTS

Of the 452 patients with OHCA enrolled in the J-PULSE-HYPO study, 431 were analyzed. NMB was used in 353 patients (81.9%). Multivariable logistic regression analysis revealed that NMB use was not independently associated with favorable outcomes [odds ratio (OR), 0.96; 95% confidence interval (CI), 0.42-2.18; p = .918)] or survival at discharge (OR, 0.83; 95% CI, 0.31-2.02; p = .688). After adjusting the covariates, the predicted probabilities did not reveal significant differences between NMB use and non-NMB use in the respective mean (95% CI) values for favorable neurological outcomes [53.6 (50.2-57.0) % vs. 58.0 (50.4-65.6) %, p = .304], and survival rates [77.1 (74.7-79.5) % vs. 75.8 (70.5-81.0) %, p = .647].

CONCLUSIONS

The NMB use during TTM was not associated with favorable neurological outcomes and survival rate in patients with OHCA.

Effects of Osmotic Therapy on Pupil Reactivity: Quantification Using Pupillometry in Critically Ill Neurologic Patients

BACKGROUND

Osmotic therapy is a critical component of medical management for cerebral edema. While up to 90% of neurointensivists report using these treatments, few quantitative clinical measurements guide optimal timing, dose, or administration frequency. Its use is frequently triggered by a qualitative assessment of neurologic deterioration and/or pupil size, and anecdotally appears to improve pupil asymmetry suggestive of uncal herniation. However, subjective pupil assessment has poor reliability, making it difficult to detect or track subtle changes. We hypothesized that osmotic therapy reproducibly improves quantitative pupil metrics.

METHODS

We included patients at two centers who had recorded quantitative pupil measurements within 2 h before and after either 20% mannitol or 23.4% hypertonic saline in the neurosciences intensive care unit. The primary outcome was the Neurologic Pupil Index (NPi), a composite metric ranging from 0 to 5 in which > 3 is considered normal. Secondary outcomes included pupil size, percent change, constriction and dilation velocity, and latency. Results were analyzed with Wilcoxon signed-rank tests, Chi-square and multi-level linear regression to control for other edema-reducing interventions.

RESULTS

Out of 72 admissions (403 paired pupil observations), NPi significantly differed within 2 h of osmotic therapy when controlling for other commonly used interventions in our whole cohort (β = 0.08, p = 0.0168). The effect was most pronounced (β = 0.57) in patients with abnormal NPi prior to intervention (p = 0.0235).

CONCLUSIONS

Pupil reactivity significantly improves after osmotic therapy in a heterogenous critically ill population when controlling for various other interventions. Future work is necessary to determine dose-dependent effects and clinical utility.

Management of Intracranial Pressure: Part I: Pharmacologic Interventions

Dangerous, sustained elevation in intracranial pressure (ICP) is a risk for any patient following severe brain injury. Intracranial pressure elevations that do not respond to initial management are considered refractory to treatment, or rICP. Patients are at significant risk of secondary brain injury and permanent loss of function resulting from rICP. Both nonpharmacologic and pharmacologic interventions are utilized to intervene when a patient experiences either elevation in ICP or rICP. In part 1 of this 2-part series, pharmacologic interventions are discussed. Opioids, sedatives, osmotic diuretics, hypertonic saline solutions, and barbiturates are drug classes that may be used in an attempt to normalize ICP and prevent secondary injury. Nursing care of these patients includes collaboration with an interprofessional team and is directed toward patient and family comfort. The utilization of an evidence-based guideline for the management of rICP is strongly encouraged to improve patient outcomes.

Prophylactic Anticonvulsants in Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Prophylactic anticonvulsants are routinely prescribed in the acute setting for intracerebral hemorrhage (ICH) patients, but some studies have reported an association with worse outcomes. We sought to characterize the prevalence and predictors of prophylactic anticonvulsant administration after ICH as well as guideline adherence. We also sought to determine whether prophylactic anticonvulsants were independently associated with poor outcome.

METHODS

We performed a retrospective study of primary ICH in our two academic centers. We used a propensity matching approach to make treated and non-treated groups comparable. We conducted multiple logistic regression analysis to identify independent predictors of prophylactic anticonvulsant initiation and its association with poor outcome as measured by modified Rankin score.

RESULTS

We identified 610 patients with primary ICH, of whom 98 were started on prophylactic anticonvulsants. Levetiracetam (97%) was most commonly prescribed. Age (OR 0.97, 95% CI 0.95-0.99, p < .001), lobar location (OR 2.94, 95% CI 1.76-4.91, p < .001), higher initial National Institutes of Health Stroke Scale (NIHSS) score (OR 2.31, 95% CI 1.40-3.79, p = .001), craniotomy (OR 3.06, 95% CI 1.51-6.20, p = .002), and prior ICH (OR 2.36, 95% CI 1.10-5.07, p = .028) were independently associated with prophylactic anticonvulsant initiation. Prophylactic anticonvulsant use was not associated with worse functional outcome [modified Rankin score (mRS) 4-6] at hospital discharge or with increased case-fatality. There was no difference in prescribing patterns after 2010 guideline publication.

DISCUSSION

Levetiracetam was routinely prescribed following ICH and was not associated with worse outcomes. Future investigations should examine the effect of prophylactic levetiracetam on cost and neuropsychological outcomes as well as the role of continuous EEG in identifying subclinical seizures.

Impact of a Pharmacist-Driven Prothrombin Complex Concentrate Protocol on Time to Administration in Patients with Warfarin-associated Intracranial Hemorrhage

Introduction

Advancements in the treatment of warfarin-associated intracranial hemorrhage (ICH) include the use of four-factor prothrombin complex concentrate (4F-PCC), which has demonstrated more rapid reversal of the international normalized ratio (INR) when compared with fresh frozen plasma. A pharmacist-driven protocol for 4F-PCC was implemented within our institution, which allows for pharmacist approval of 4F-PCC in patients diagnosed with warfarin-associated ICH and an INR ≥2. The pharmacist is responsible for determining the appropriate dose of 4F-PCC, preparation, bedside delivery, and order entry into the electronic medical record. Prior to implementation of the new protocol, the blood bank was responsible for 4F-PCC approval, dosing, product preparation, and arranging delivery with emergency department (ED) staff. The purpose of this study was to evaluate the impact of a pharmacist-driven protocol on time to 4F-PCC administration in warfarin-associated ICH.

Methods

We performed a retrospective review of consecutive patients who received 4F-PCC in a single ED from September 2015 through February 2017. Patients ≥18 years old were eligible for inclusion based on three criteria: confirmed diagnosis of ICH; confirmed warfarin use; and INR ≥2. Secondary outcomes included dose of 4F-PCC in concordance with INR and weight-based dosing recommendations and hospital protocol, as well as concomitant intravenous vitamin K administration.

Results

A total of 48 patients met inclusion criteria for the study with 24 patients in each protocol group. The median time to administration of 4F-PCC in the pharmacist-driven protocol group was 35 minutes (interquartile range [IQR] [25–62]; range, 11–133) compared with 70 minutes (IQR [34–89]; range, 14–244) in the pre-protocol group (p=0.034). We saw no differences for appropriate 4F-PCC dosing based on INR and patient weight between the two groups.

Conclusion

Implementation of a pharmacist-driven protocol for 4F-PCC in the ED at our institution significantly reduced time to administration in patients presenting with warfarin-associated ICH.

Autoimmune Encephalitis at the Neurological Intensive Care Unit: Etiologies, Reasons for Admission and Survival

Background

Early recognition and treatment of autoimmune encephalitis (AE) has become an essential issue in clinical practice. However, little is known about patients with deteriorating conditions and the need for intensive care treatment. Here, we aimed to characterize underlying aetiologies, clinical symptoms, reasons for intensive care admission, and mortality of critically ill patients with AE.

Methods

We conducted a retrospective chart review of all patients with “definite” or “probable” diagnoses of AE treated at our neurological intensive care unit between 2002 and 2015. We collected and analyzed clinical, paraclinical, laboratory findings and assessed the mortality at last follow-up based on patient records.

Results

Twenty-seven patients [median age 55 years (range 25–87), male = 16] were included. Thirteen (48%) had “definite” AE. The most common reasons for admission were status epilepticus (7/27, 26%) and delirium (4/27, 15%). One-year survival was 82%, all five deceased were male, and 3 (60%) of them had “probable” disease. The non-survivors (median follow-up 1 year) were more likely to have underlying cancer and higher need for respiratory support compared to the survivors (p < 0.041, and p = 0.004, respectively).

Conclusions

Clinical presentations and outcomes in critically ill patients with AE are diverse, and the most common leading cause for intensive care unit admission was status epilepticus. The association of comorbid malignancy and the need for mechanical ventilation with mortality deserves further attention.

Electronic supplementary material

The online version of this article (doi:10.1007/s12028-016-0370-7) contains supplementary material, which is available to authorized users.

Critical Care Management Focused on Optimizing Brain Function After Cardiac Arrest

The discussion of neurocritical care management in post-cardiac arrest syndrome (PCAS) has generally focused on target values used for targeted temperature management (TTM). There has been less attention paid to target values for systemic and cerebral parameters to minimize secondary brain damage in PCAS. And the neurologic indications for TTM to produce a favorable neurologic outcome remain to be determined. Critical care management of PCAS patients is fundamental and essential for both cardiologists and general intensivists to improve neurologic outcome, because definitive therapy of PCAS includes both special management of the cause of cardiac arrest, such as coronary intervention to ischemic heart disease, and intensive management of the results of cardiac arrest, such as ventilation strategies to avoid brain ischemia. We reviewed the literature and the latest research about the following issues and propose practical care recommendations. Issues are (1) prediction of TTM candidate on admission, (2) cerebral blood flow and metabolism and target value of them, (3) seizure management using continuous electroencephalography, (4) target value of hemodynamic stabilization and its method, (5) management and analysis of respiration, (6) sedation and its monitoring, (7) shivering control and its monitoring, and (8) glucose management. We hope to establish standards of neurocritical care to optimize brain function and produce a favorable neurologic outcome.

The Benefit of Neuromuscular Blockade in Patients with Postanoxic Myoclonus Otherwise Obscuring Continuous Electroencephalography (CEEG)

Introduction. Myoclonus status epilepticus is independently associated with poor outcome in coma patients after cardiac arrest. Determining if myoclonus is of cortical origin on continuous electroencephalography (CEEG) can be difficult secondary to the muscle artifact obscuring the underlying CEEG. The use of a neuromuscular blocker can be useful in these cases. Methods. Retrospective review of CEEG in patients with postanoxic myoclonus who received cisatracurium while being monitored. Results. Twelve patients (mean age: 53.3 years; 58.3% male) met inclusion criteria of clinical postanoxic myoclonus. The initial CEEG patterns immediately prior to neuromuscular blockade showed myoclonic artifact with continuous slowing (50%), burst suppression with myoclonic artifact (41.7%), and continuous myogenic artifact obscuring CEEG (8.3%). After intravenous administration of cisatracurium (0.1 mg–2 mg), reduction in artifact improved quality of CEEG recordings in 9/12 (75%), revealing previously unrecognized patterns: continuous EEG seizures (33.3%), lateralizing slowing (16.7%), burst suppression (16.7%), generalized periodic discharges (8.3%), and, in the patient who had an initially uninterpretable CEEG from myogenic artifact, continuous slowing. Conclusion. Short-acting neuromuscular blockade is useful in determining background cerebral activity on CEEG otherwise partially or completely obscured by muscle artifact in patients with postanoxic myoclonus. Fully understanding background cerebral activity is important in prognostication and treatment, particularly when there are underlying EEG seizures.

Erratum to: Neurocritical care update

[This corrects the article DOI: 10.1186/s40560-016-0141-8.].

Neurocritical care update

This update comprises six important topics under neurocritical care that require reevaluation. For post-cardiac arrest brain injury, the evaluation of the injury and its corresponding therapy, including temperature modulation, is required. Analgosedation for target temperature management is an essential strategy to prevent shivering and minimizes endogenous stress induced by catecholamine surges. For severe traumatic brain injury, the diverse effects of therapeutic hypothermia depend on the complicated pathophysiology of the condition. Continuous electroencephalogram monitoring is an essential tool for detecting nonconvulsive status epilepticus in the intensive care unit (ICU). Neurocritical care, including advanced hemodynamic monitoring, is a fundamental approach for delayed cerebral ischemia following subarachnoid hemorrhage. We must be mindful of the high percentage of ICU patients who may develop sepsis-associated brain dysfunction.