Amplification of acute focal ischemic deficit by narcotics

Reappearance of Neurological Deficits in Pathologic Brain: Are Sedatives and Opioids Culprits? A Systematic Review

Following a brain insult, focal neurological deficits may develop. Despite resolution of these deficits with time, the subsequent administration of sedative medications and opioids may lead to recrudescence of previous neurological deficits. Therefore, the present systematic review aims to explore the role of different sedatives and opioid analgesics at reproducing focal neurological deficits in patients with previous brain insults undergoing surgery. Our PRISMA compliant systematic review covering the literature from 1990 to 2020 showed a consistent reoccurrence of neurological deficits following administration of benzodiazepines and opioids across 12 studies. It appears that in all studies, the manifestations were transient and affected mostly middle-aged patients (45 to 67 y of age). In addition, benzodiazepines and opioid antagonism by naloxone and flumazenil reverses the unmasking of prior neurological deficits. In contrast, it is not clear based on our study whether the unmasking or worsening of neurological deficits occurs following recent injuries or an older brain insult, although for most patients it appears to be the former. Future studies are needed to elucidate the mechanisms involved in unmasking prior deficits and/or extension of prior injuries by sedative and opioid analgesics. This review will aid in developing prospective studies on individual sedative medications and their effects on unmasking neurological deficits in patients with multiple brain pathologies.

Difference in imaging biomarkers between transient and permanent neurological deficits after endovascular treatment of cerebrovascular aneurysms

OBJECTIVE

The literature suggests that blood-brain barrier disruption (BBBD) plays a significant role in the development of neurological events in patients with diffusion-weighted imaging (DWI) that is negative for lesions. In this prospective, single-center cohort study, the authors compared the imaging characteristics of patients suffering transient neurological events (TNEs) with those in patients suffering permanent neurological events (PNEs) after having undergone elective embolization of unruptured intracranial aneurysms.

METHODS

This prospective cohort study was conducted between July 2016 and June 2019. Inclusion criteria were adults undergoing elective neuroendovascular procedures and the absence of contraindications to MRI. All subjects underwent brain MRI including postcontrast FLAIR (pcFLAIR) sequences for evaluation of BBBD within 24 hours postprocedure.

RESULTS

In total, 128 patients harboring 133 unruptured aneurysms were enrolled, 109 of whom (85.2%) showed some degree of BBBD on pcFLAIR MRI and 50 of whom (39.1%) suffered an ischemic insult per DWI. In total, 23 patients (18%) suffered neurological complications, 16 of which (12.5%) were TNEs and 7 of which (5.5%) were PNEs. The median extent of BBBD was focal in asymptomatic patients as compared to hemispheric and lobar in the TNE and PNE groups, respectively (p < 0.001). The American Society of Anesthesiologists physical status classification predicted the extent of BBBD (p = 0.046). Lesions on DWI were noted in 34 asymptomatic patients (32.4%) compared to 9 patients (56.3%) with TNEs and all 7 patients (100%) with PNEs (p < 0.001). The median number of DWI lesions was 0 (range 0-18 lesions) in the asymptomatic group compared to 1.5 (range 0-8 lesions) and 8 (range 1-13 lesions) in the TNE and PNE groups, respectively (p < 0.001). Smoking (p = 0.008), older age (p = 0.002), and longer surgery (p = 0.006) were positively associated with the number of lesions on DWI. On multivariate analysis, intraarterial verapamil (p = 0.02, OR 8.01, 95% CI 1.35-47.43) and extent of BBBD (p < 0.001, OR 58.58, 95% CI 9.48-361.84) were positively associated with the development of TNEs, while intravenous infusion of midazolam during surgery (p = 0.02, OR 6.03, 95% CI 1.29-28.20) was negatively associated. An increased number of lesions on DWI was the only significant predictor for the development of PNEs (p < 0.001, OR 49.85, 95% CI 5.56-447.10).

CONCLUSIONS

An increasing extent of BBBD was associated with the development of TNEs, whereas an increasing number of lesions on DWI was significantly associated with the development of PNEs. BBBD imaging using pcFLAIR may serve as a valuable biomarker for detecting subtle cerebral ischemia and stratifying the risk for ischemic events.

Recrudescence of Old Stroke Deficits Among Transient Neurological Attacks

Background

Recrudescence of old stroke deficits (ROSD) is a reported cause of transient neurological symptoms, but it is not well characterized.

Objective

We sought to determine the prevalence, potential triggers, and clinical outcome of ROSD in a cohort of patients presenting with acute transient neurological attack (TNA) and absent acute pathology on brain imaging.

Methods

We retrospectively analyzed 340 consecutive patients who presented with TNA and no acute pathology on brain imaging that were included in an institutional stroke registry between February 2013 and April 2015. The presumed TNA cause was categorized as transient ischemic attack (TIA), ROSD, and other cause. Baseline characteristics, triggers, cardiovascular complications within 90 days, and death were recorded.

Results

The prevalence of ROSD in the studied cohort was 10% (34/340). Infectious stressors and acute metabolite derangements were more common in ROSD compared to TIA (P < .05, each). Compared to TIA and the other TNA, ROSD was more likely to have more than 1 acute stressor (P < .001). Patients with ROSD had similar vascular risk factors compared to TIA (P > .05), including hypertension, diabetes mellitus, peripheral vascular disease, hyperlipidemia, and similarly used HMG-CoA reductase inhibitor, antihypertensive, and antiplatelet medications. Among the patients with an available 90-day follow-up (n = 233), cardiovascular events were more frequent in the TIA group as compared to other TNA (P < .05).

Conclusion

ROSD is common and distinct from TIA and is associated with a triggering physiologic reaction leading to transient reemergence of prior neurologic deficits. Further study of the mechanism of this phenomenon is needed to help better identify these patients.

Recrudescence of Focal Stroke Symptoms during Pain Management with Hydromorphone

Patients who have recovered from a prior stroke may experience a reemergence of their original stroke syndrome secondary to metabolic derangements, sedation, infection, and/or fatigue. Critically, the molecular/cellular mechanisms mediating symptom recurrence after exposure to analgesic agents remain unknown. Accordingly, herein, we report a unique case of a patient with hydromorphone-induced recrudescence 30 years after her initial stroke event(s) and in so doing propose a putative mechanism related to post-infarction functional neuroplasticity.

Opioid overdose in a child: case report and discussion with emphasis on neurosurgical implications

In environments in which opioids are increasingly abused for recreation, children are becoming more at risk for both accidental and nonaccidental intoxication. In toxic doses, opioids can cause potentially lethal acute leukoencephalopathy, which has a predilection for the cerebellum in young children. The authors present the case of a 2-year-old girl who suffered an accidental opioid overdose, presenting with altered mental status requiring cardiorespiratory support. She required emergency posterior fossa decompression, partial cerebellectomy, and CSF drainage due to cerebellar edema compressing the fourth ventricle. To the authors' knowledge, this is the first report of surgical decompression used to treat cerebellar edema associated with opioid overdose in a child.

The Benefit of Hypothermia in Experimental Ischemic Stroke is Not Affected by Pethidine

Background

Hypothermia is a promising experimental treatment for acute ischemic stroke. Human trials are still at an early stage, with the focus now on using hypothermia in awake patients. Pethidine (meperidine) is the principle agent used to control shivering in humans; however, whether it has any modulating effects on the neuroprotective efficacy of hypothermia is unknown.

Aim

The aim of this study was to determine if pethidine influences the neuroprotective effect of hypothermia in experimental stroke.

Methods

Seventy-two male spontaneously hypertensive rats were anesthetized with isoflurane and randomly assigned to either normothermia (37·4°C rectal temperature); hypothermia (33°C maintained for 130 mins); normothermia plus pethidine (2·5 mg/kg); or hypothermia plus pethidine. Temporary (90 mins) endovascular occlusion of the middle cerebral artery was induced blinded to treatment allocation and was confirmed with laser Doppler flowmetry. Pethidine and cooling were started immediately after vessel occlusion. Animals in the normothermia group had active temperature management using a heat lamp and fan. Assessments of outcome were carried out 24 after the induction of injury.

Results

Thirteen animals met our prespecified criteria for exclusion, and data for 59 rats were presented here. Hypothermia was associated with a 63% reduction in infarct size, and pethidine had no significant impact on the efficacy of hypothermia. No effects were observed in neurobehavioral outcome or edema volume across experimental groups.

Conclusions

The effects of hypothermia in a model of focal ischemia are not affected by administration of pethidine.