Twenty-four-Hour blood pressure variability after acute ischemic stroke

Importance of blood pressure monitoring in the acute phase of stroke. An update

INTRODUCTION

The evaluation of blood pressure (BP) is essential in the acute phase of stroke. Although ambulatory blood pressure monitoring (ABPM) is a validated method for BP control, there are few studies assessing the usefulness of ABPM in the acute phase of stroke.

DEVELOPMENT

A systematic review was carried out according to the PRISMA criteria in the PubMed/Medline and Scopus databases. Those articles that analysed the use of ABPM in the first days after suffering a stroke from 1992 to 2022 were selected. Those articles focused on the post-acute or sequelae phase of the stroke, with a sample size of less than 20 and those where the primary objective was different from the defined one. A total of 28 articles were included.

CONCLUSIONS

The use of ABPM in patients with recent stroke demonstrates that the normal circadian profile of BP is altered in more than two-thirds of patients and that this will be fundamentally conditioned by the haemodynamic changes that occur on autoregulation of cerebral blood flow, the type of stroke or the response to treatment. Furthermore, these changes in BP have prognostic implications and are correlated with functional status, stroke recurrence and mortality, among others. However, although they continue to be a growing area of research, new studies are needed to clarify the real role of this technique in patients with acute stroke.

Circadian Factors in Stroke: A Clinician's Perspective

Stroke remains one of the leading causes of mortality and long-term and permanent disability worldwide despite technological innovations and developments in pharmacotherapy. In the last few decades, the growing data have evidenced the role of the circadian system in brain vulnerability to damage, the development and evolution of stroke, and short-term and long-term recovery. On the other hand, the stroke itself can affect the circadian system via direct injury of specific brain structures involved in circadian regulation (i.e., hypothalamus, retinohypothalamic tracts, etc.) and impairment of endogenous regulatory mechanisms, metabolic derangement, and a neurogenic inflammatory response in acute stroke. Moreover, the disruption of circadian rhythms can occur or exacerbate as a result of exogenous factors related to hospitalization itself, the conditions in the intensive care unit and the ward (light, noise, etc.), medication (sedatives and hypnotics), and loss of external factors entraining the circadian rhythms. In the acute phase of stroke, patients demonstrate abnormal circadian variations in circadian biomarkers (melatonin, cortisol), core body temperature, and rest-activity patterns. The approaches aimed at the restoration of disrupted circadian patterns include pharmacological (melatonin supplementation) and non-medication (bright light therapy, shifting feeding schedules, etc.) interventions; however, their effects on short- and long-term recovery after stroke are not well understood.

Continuous hemodynamic monitoring in acute stroke: an exploratory analysis

INTRODUCTION

Non-invasive, continuous hemodynamic monitoring is entering the clinical arena. The primary objective of this study was to test the feasibility of such monitoring in a pilot sample of Emergency Department (ED) stroke patients. Secondary objectives included analysis of hemodynamic variability and correlation of continuous blood pressure measurements with standard measurements.

METHODS

This study was a secondary analysis of 7 stroke patients from a prospectively collected data set of patients that received 2 hours of hemodynamic monitoring in the ED. Stroke patients were included if hemorrhagic or ischemic stroke was confirmed by neuroimaging, and symptom onset was within 24 hours. They were excluded for the presence of a stroke mimic or transient ischemic attack. Monitoring was performed using the Nexfin device (Edwards Lifesciences, Irvine CA).

RESULTS

The mean age of the cohort was 71 ± 17 years, 43% were male, and the mean National Institute of Health Stroke Scale (NIHSS) was 6.9 ± 5.5. Two patients had hemorrhagic stroke. We obtained 42,456 hemodynamic data points, including beat-to-beat blood pressure measurements with variability of 18 mmHg and cardiac indices ranging from 1.8 to 3.6 l/min/m2. The correlation coefficient between continuous blood pressure measurements with the Nexfin device and standard ED readings was 0.83.

CONCLUSION

This exploratory investigation revealed that continuous, noninvasive monitoring in the ED is feasible in acute stroke. Further research is currently underway to determine how such monitoring may impact outcomes in stroke or replace the need for invasive monitoring.