Hypoxic-ischemic brain injury and prognosis after cardiac arrest

Prediction of patient survival following postanoxic coma using EEG data and clinical features

Electroencephalography (EEG) is an effective and non-invasive technique commonly used to monitor brain activity and assist in outcome prediction for comatose patients post cardiac arrest. EEG data may demonstrate patterns associated with poor neurological outcome for patients with hypoxic injury. Thus, both quantitative EEG (qEEG) and clinical data contain prognostic information for patient outcome. In this study we use machine learning (ML) techniques, random forest (RF) and support vector machine (SVM) to classify patient outcome post cardiac arrest using qEEG and clinical feature sets, individually and combined. Our ML experiments show RF and SVM perform better using the joint feature set. In addition, we extend our work by implementing a convolutional neural network (CNN) based on time-frequency images derived from EEG to compare with our qEEG ML models. The results demonstrate significant performance improvement in outcome prediction using non-feature based CNN compared to our feature based ML models. Implementation of ML and DL methods in clinical practice have the potential to improve reliability of traditional qualitative assessments for postanoxic coma patients.

Palmitic acid methyl ester is a novel neuroprotective agent against cardiac arrest

We previously discovered that palmitic acid methyl ester (PAME) is a potent vasodilator first identified and released from the superior cervical ganglion and remain understudied. Thus, we investigated PAME's role in modulating cerebral blood flow (CBF) and neuroprotection after 6 min of cardiac arrest (model of global cerebral ischemia). Our results suggest that PAME can enhance CBF under normal physiological conditions, while administration of PAME (0.02 mg/kg) immediately after cardiopulmonary resuscitation can also enhance CBF in vivo. Additionally, functional learning and spatial memory assessments (via T-maze) 3 days after asphyxial cardiac arrest (ACA) suggest that PAME-treated rats have improved learning and memory recovery versus ACA alone. Furthermore, improved neuronal survival in the CA1 region of the hippocampus were observed in PAME-treated, ACA-induced rats. Altogether, our findings suggest that PAME can enhance CBF, alleviate neuronal cell death, and promote functional outcomes in the presence of ACA.

Neural injury of the Papez circuit following hypoxic-ischemic brain injury: A case report

INTRODUCTION

Hypoxic-ischemic brain injury (HI-BI), a result of oxygen deprivation of the brain, is accompanied by memory impairment. In this study, we report on a patient with neural injury of the Papez circuit following HI-BI, demonstrated by diffusion tensor tractography (DTT).

CLINICAL FINDINGS/PATIENT CONCERNS

A 48-year-old male patient suffered spontaneous cardiopulmonary arrest and underwent cardiopulmonary resuscitation for approximately 20 minutes with the concomitant oxygen deprivation leading to HI-BI. The patient showed severe memory impairment at 10 weeks after onset: a Mini-Mental State Examination score of 11 (full score: 30, cut-off score < 24), and examination using the memory function test was not possible due to severe cognitive deficit.

OUTCOMES

On 10-week DTT, discontinuation of the fornical column was observed in both hemispheres and thinning of the thalamocingulate tract was observed in the right hemisphere and nonreconstruction in the left hemisphere.

CONCLUSION

Using DTT, neural injury of the Papez circuit was demonstrated in a patient with memory impairment following HI-BI. These results suggest that analysis of the Papez circuit using DTT could provide beneficial information by detecting injury of the Papez circuit that cannot be detected on conventional brain MRI in patients with HI-BI.

Shen-Fu Injection () alleviates post-resuscitation myocardial dysfunction by up-regulating expression of sarcoplasmic reticulum Ca(2+)-ATPase

OBJECTIVE

To compare the effect of Shen-Fu Injection (SFI) and epinephrine on the expression of sarcoplasmic reticulum Ca(2+) ATPase 2a (SERCA2a) in a pig model with post-resuscitation myocardial dysfunction.

METHODS

Ventricular fibrillation (VF) was electrically induced in Wu-zhi-shan miniature pigs. After 8 min of untreated VF and 2 min of cardiopulmonary resuscitation (CPR), all animals were randomly administered a bolus injection of saline placebo (SA group, n=10), SFI (0.8 mg/kg, SFI group, n=10) or epinephrine (20 μg/kg, EPI group, n=10). After 4 min of CPR, a 100-J shock was delivered. If the defibrillation attempt failed to attain restoration of spontaneous circulation (ROSC), manual chest compressions were rapidly resumed for a further 2 min followed by a second defibrillation attempt. Hemodynamic variables were recorded, and plasma concentrations of catecholamines were measured. Adenylate cyclase (AC), cyclic adenosine monophosphate (cAMP) and the expressions of β1-adrenoceptor (AR) and SERCA 2a were determined.

RESULTS

Cardiac output, left ventricular dp/dtmax and negative dp/dtmax were significantly higher in the SFI group than in the SA and EPI groups at 4 and 6 h after ROSC. The expression of β1-AR and SERCA2a at 24 h after ROSC were significantly higher in the SFI group than in the SA and EPI groups (P<0.05 or P<0.01).

CONCLUSIONS

The administration of epinephrine during CPR decreased the expression of SERCA2a and aggravated postresuscitation myocardial function (P<0.01). SFI attenuated post-resuscitation myocardial dysfunction, and the mechanism might be related to the up-regulation of SERCA2a expression.

Therapeutic effects of Shenfu Injection on post-cardiac arrest syndrome

Survival rates after cardiac arrest have not changed substantially over the past 5 decades. Postcardiac arrest (CA) syndrome (PCAS) is the primary reason for the high mortality rate after successful restoration of spontaneous circulation (ROSC). Intravenous administration of Shenfu Injection (, SFI) may attenuate post-CA myocardial dysfunction and cerebral injury, inhibit systemic ischemia/reperfusion responses, and treat underlying diseases. In this article, we reviewed the therapeutic effects of SFI in PCAS. SFI might be useful in the treatment of PCAS, incorporating the multi-link and multi-target advantages of Chinese medicine into PCAS management. Further experimental and clinical research to verify the therapeutic effects of SFI in PCAS is required.