scholarly journals Optimizing Cerebral Autoregulation May Decrease Neonatal Regional Hypoxic-Ischemic Brain Injury

2016 ◽  
Vol 39 (1-4) ◽  
pp. 248-256 ◽  
Author(s):  
Jennifer K. Lee ◽  
Andrea Poretti ◽  
Jamie Perin ◽  
Thierry A.G.M. Huisman ◽  
Charlamaine Parkinson ◽  
...  

Background: Therapeutic hypothermia provides incomplete neuroprotection for neonatal hypoxic-ischemic encephalopathy (HIE). We examined whether hemodynamic goals that support autoregulation are associated with decreased brain injury and whether these relationships are affected by birth asphyxia or vary by anatomic region. Methods: Neonates cooled for HIE received near-infrared spectroscopy autoregulation monitoring to identify the mean arterial blood pressure with optimized autoregulatory function (MAPOPT). Blood pressure deviation from MAPOPT was correlated with brain injury on MRI after adjusting for the effects of arterial carbon dioxide, vasopressors, seizures, and birth asphyxia severity. Results: Blood pressure deviation from MAPOPT related to neurologic injury in several regions independent of birth asphyxia severity. Greater duration and deviation of blood pressure below MAPOPT were associated with greater injury in the paracentral gyri and white matter. Blood pressure within MAPOPT related to lesser injury in the white matter, putamen and globus pallidus, and brain stem. Finally, blood pressures that exceeded MAPOPT were associated with reduced injury in the paracentral gyri. Conclusions: Blood pressure deviation from optimal autoregulatory vasoreactivity was associated with MRI markers of brain injury that, in many regions, were independent of the initial birth asphyxia. Targeting hemodynamic ranges to optimize autoregulation has potential as an adjunctive therapy to hypothermia for HIE.

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiuyun Liu ◽  
Aylin Tekes ◽  
Jamie Perin ◽  
May W. Chen ◽  
Bruno P. Soares ◽  
...  

Dysfunctional cerebrovascular autoregulation may contribute to neurologic injury in neonatal hypoxic-ischemic encephalopathy (HIE). Identifying the optimal mean arterial blood pressure (MAPopt) that best supports autoregulation could help identify hemodynamic goals that support neurologic recovery. In neonates who received therapeutic hypothermia for HIE, we hypothesized that the wavelet hemoglobin volume index (wHVx) would identify MAPopt and that blood pressures closer to MAPopt would be associated with less brain injury on MRI. We also tested a correlation-derived hemoglobin volume index (HVx) and single- and multi-window data processing methodology. Autoregulation was monitored in consecutive 3-h periods using near infrared spectroscopy in an observational study. The neonates had a mean MAP of 54 mmHg (standard deviation: 9) during hypothermia. Greater blood pressure above the MAPopt from single-window wHVx was associated with less injury in the paracentral gyri (p = 0.044; n = 63), basal ganglia (p = 0.015), thalamus (p = 0.013), and brainstem (p = 0.041) after adjustments for sex, vasopressor use, seizures, arterial carbon dioxide level, and a perinatal insult score. Blood pressure exceeding MAPopt from the multi-window, correlation HVx was associated with less injury in the brainstem (p = 0.021) but not in other brain regions. We conclude that applying wavelet methodology to short autoregulation monitoring periods may improve the identification of MAPopt values that are associated with brain injury. Having blood pressure above MAPopt with an upper MAP of ~50–60 mmHg may reduce the risk of brain injury during therapeutic hypothermia. Though a cause-and-effect relationship cannot be inferred, the data support the need for randomized studies of autoregulation and brain injury in neonates with HIE.


2017 ◽  
Vol 28 (1) ◽  
pp. 55-65 ◽  
Author(s):  
Ronald B. Easley ◽  
Bradley S. Marino ◽  
Jacky Jennings ◽  
Amy E. Cassedy ◽  
Kathleen K. Kibler ◽  
...  

AbstractBackgroundCerebrovascular reactivity monitoring has been used to identify the lower limit of pressure autoregulation in adult patients with brain injury. We hypothesise that impaired cerebrovascular reactivity and time spent below the lower limit of autoregulation during cardiopulmonary bypass will result in hypoperfusion injuries to the brain detectable by elevation in serum glial fibrillary acidic protein level.MethodsWe designed a multicentre observational pilot study combining concurrent cerebrovascular reactivity and biomarker monitoring during cardiopulmonary bypass. All children undergoing bypass for CHD were eligible. Autoregulation was monitored with the haemoglobin volume index, a moving correlation coefficient between the mean arterial blood pressure and the near-infrared spectroscopy-based trend of cerebral blood volume. Both haemoglobin volume index and glial fibrillary acidic protein data were analysed by phases of bypass. Each patient’s autoregulation curve was analysed to identify the lower limit of autoregulation and optimal arterial blood pressure.ResultsA total of 57 children had autoregulation and biomarker data for all phases of bypass. The mean baseline haemoglobin volume index was 0.084. Haemoglobin volume index increased with lowering of pressure with 82% demonstrating a lower limit of autoregulation (41±9 mmHg), whereas 100% demonstrated optimal blood pressure (48±11 mmHg). There was a significant association between an individual’s peak autoregulation and biomarker values (p=0.01).ConclusionsIndividual, dynamic non-invasive cerebrovascular reactivity monitoring demonstrated transient periods of impairment related to possible silent brain injury. The association between an impaired autoregulation burden and elevation in the serum brain biomarker may identify brain perfusion risk that could result in injury.


2018 ◽  
Vol 28 (6) ◽  
pp. 804-810 ◽  
Author(s):  
Neil D. Patel ◽  
Patrick M. Sullivan ◽  
Cheryl M. Takao ◽  
Sarah Badran ◽  
Joseph Ahdoot ◽  
...  

AbstractBackgroundOne indication for intervention in coarctation of the aorta is a peak-to-peak gradient >20 mmHg. Gradients may be masked in patients under general anaesthesia and may be higher during exercise. Isoproterenol was given during cardiac catheterisation to simulate a more active physiologic state.ObjectivesWe aimed to describe the haemodynamic effects of isoproterenol in patients with coarctation and the impact of intervention on the elicited gradients.MethodsA retrospective study was performed on two-ventricle patients who underwent cardiac catheterisation for coarctation with isoproterenol testing.Results25 patients received isoproterenol before and after intervention. With isoproterenol, the mean diastolic (p=0.0015) and mean arterial (p=0.0065) blood pressures proximal to the coarctation decreased significantly. The mean systolic, diastolic, and mean arterial blood pressures distal to the coarctation decreased significantly (p<0.0001). In patients with a baseline gradient ⩽20 mmHg (n=17) at catheterisation, the median gradient increased from 10 (0–20) to 30 (15–50) mmHg (p<0.0001) with isoproterenol. Of these, 15 patients developed a gradient >20 mmHg. Post intervention, the median gradient decreased to 2 (0–29) mmHg, versus baseline, p=0.005, and with isoproterenol it decreased to 8 (0–27) mmHg, versus pre-intervention isoproterenol, p<0.0001. There were significant improvements in the gradients by Doppler (<0.0001) and by blood pressure cuff (p=0.0313). The gradients on isoproterenol best correlated with gradients by blood pressure cuff in the awake state (R2=0.76, p<0.0001).ConclusionsIsoproterenol can be a useful tool to assess the significance of a coarctation and the effectiveness of an intervention. Percutaneous interventions can effectively reduce the gradients elicited by isoproterenol.


PEDIATRICS ◽  
1996 ◽  
Vol 97 (3) ◽  
pp. 336-342 ◽  
Author(s):  
Thomas Hegyi ◽  
Mujahid Anwar ◽  
Mary Terese Carbone ◽  
Barbara Ostfeld ◽  
Mark Hiatt ◽  
...  

Objective. To examine the arterial blood pressure in the first week of life in a healthy premature population. Design. Population-based cohort study. Setting. Three intensive care nurseries in central New Jersey. Patients. Premature infants with birth weights less than 2000 g. Main Outcome Measures. We documented daily maximum and minimum systolic and maximum and minimum diastolic blood pressures during the first 7 days of life. To examine the effects on these ranges of blood pressure of specific risk factors likely to affect blood pressure, we identified four groups of infants: (1) healthy infants without any of the major risk factors (n = 193); (2) infants who were mechanically ventilated but free of any of the other conditions (n = 225); (3) infants with histories of maternal hypertension or preeclampsia (n = 38); and (4) infants with low Apgar scores (less than 3 at 1 minute and less than 6 at 5 minutes) regardless of the presence of other conditions (n = 86). Results. Blood pressure increased steadily in the first week of life in all four groups. There was no relationship between any of the four blood pressure variables, or trends in blood pressure over time, with birth weight, gender, or race. Regression equations (based on all infants with available data) for blood pressure ranges by day of life revealed that the maximum systolic blood pressure increased by 2.6 mm Hg/d, the minimum systolic blood pressure increased by 1.8 mm Hg/d, the maximum diastolic blood pressure increased by 2.0 mm Hg/d, and the minimum diastolic blood pressure increased by 1.3 mm Hg/d. Conclusions. Infants with birth asphyxia and ventilated infants had significantly lower systolic and diastolic blood pressures than healthy infants.


In August, 1903, I published a paper in the ‘Journal of Pathology’(1) in which I demonstrated a method experimentally producing uncompensated hear disease in an animal, which was compatible with life. This method consisted in diminishing the size of the pericardial sac by stitches, so that the diastolic filling of the heart was impeded. The main symptoms of this condition were dropsy and diminution in the amount of urine excreted. As the immediate result of this interference with the action of the heart, there occurred a rise of pressure throughout the whole systemic venous system extending as far back as the capillaries, and a fall of the mean arterial blood-pressure. Further, I found that the pressure in all the veins fell to the normal limit again within the space of about one hour, and that subsequently when dropsy was being produced, the vanous pressure in all parts of the body was normal, and the arterial pressure had almost recovered itself.


Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1867
Author(s):  
Tasbiraha Athaya ◽  
Sunwoong Choi

Blood pressure (BP) monitoring has significant importance in the treatment of hypertension and different cardiovascular health diseases. As photoplethysmogram (PPG) signals can be recorded non-invasively, research has been highly conducted to measure BP using PPG recently. In this paper, we propose a U-net deep learning architecture that uses fingertip PPG signal as input to estimate arterial BP (ABP) waveform non-invasively. From this waveform, we have also measured systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP). The proposed method was evaluated on a subset of 100 subjects from two publicly available databases: MIMIC and MIMIC-III. The predicted ABP waveforms correlated highly with the reference waveforms and we have obtained an average Pearson’s correlation coefficient of 0.993. The mean absolute error is 3.68 ± 4.42 mmHg for SBP, 1.97 ± 2.92 mmHg for DBP, and 2.17 ± 3.06 mmHg for MAP which satisfy the requirements of the Association for the Advancement of Medical Instrumentation (AAMI) standard and obtain grade A according to the British Hypertension Society (BHS) standard. The results show that the proposed method is an efficient process to estimate ABP waveform directly using fingertip PPG.


1963 ◽  
Vol 44 (3) ◽  
pp. 430-442 ◽  
Author(s):  
B. Arner ◽  
P. Hedner ◽  
T. Karlefors ◽  
H. Westling

ABSTRACT Observations were made on healthy volunteers during insulin induced hypoglycaemia (10 cases) and infusion of adrenaline (3 cases) or cortisol (1 case). In all cases a rise in the cardiac output was registered during insulin hypoglycaemia. The mean arterial blood pressure was relatively unchanged and the calculated peripheral vascular resistance decreased in all cases. A temporary rise in plasma corticosteroids was observed. After infusion of adrenaline similar circulatory changes were observed but no rise in plasma corticosteroids was found. Infusion of cortisol caused an increased plasma corticosteroid level but no circulatory changes. It is concluded that liberation of catechol amines and increased adrenocortical activity following hypoglycaemia are not necessarily interdependent.


Hypertension ◽  
2007 ◽  
Vol 49 (6) ◽  
pp. 1228-1234 ◽  
Author(s):  
Gary L. Schwartz ◽  
Kent R. Bailey ◽  
Thomas Mosley ◽  
David S. Knopman ◽  
Clifford R. Jack ◽  
...  

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Adam H de Havenon ◽  
Alexandra Kvernland ◽  
Alen Delic ◽  
Ka-ho Wong ◽  
Nazanin Sheibani ◽  
...  

Background: Recurrent stroke has higher morbidity and mortality than incident stroke. We evaluated hemodynamic risk factors for multiple recurrent strokes. Methods: We included patients in the SPS3 trial. The primary predictor was the top tertile, compared to the bottom tertile, of the mean systolic blood pressure (mSBP) and blood pressure variability represented as standard deviation (sdSBP) using blood pressures from day 30 of the trial to the end of follow-up. We excluded blood pressures from the first 30 days to reduce confounding from the trial’s intervention. We fit a logistic regression model to ≥2 recurrent strokes from day 30 to the end of follow-up and, to accurately analyze the multiple failure-time data, we ordered the multiple failure events to the Prentice, Williams and Peterson extension of the Cox proportional-hazards model. Results: We included 2,882 patients, of which 223 had a recurrent stroke and 41/223 had ≥2 recurrent strokes for a total of 272 strokes. The mean (SD) number of blood pressure readings was 78.0 (37.4). The etiology of the 272 strokes was 161 (59.2%) lacunar, 22 (8.1%) intracranial atherosclerosis, 10 (3.7%) extracranial atherosclerosis, 24 (8.8%) cardioembolic, and 55 (20.2%) cryptogenic or other. In both unadjusted and adjusted logistic regression models and PWP Cox models, the top tertile of sdSBP was consistently predictive of multiple recurrent strokes, while mSBP was not (Tables 1/2). Conclusions: We found that in patients with an index lacunar stroke, higher SBP variability, but not mean SBP, was predictive of multiple recurrent strokes of varying mechanisms.


PEDIATRICS ◽  
1973 ◽  
Vol 52 (2) ◽  
pp. 293-296
Author(s):  
Rosemary D. Leake ◽  
Paul R. Williams ◽  
William Oh

In neonatal intensive care units where direct arterial blood pressures obtained via a transducer are unavailable, a fluid-filled spinal manometer has been used. The latter method is practical and convenient although its validity has not been confirmed. This study is designed to establish the precise relationship between the blood pressure obtained by the manometric method and by direct recording via the arterial transducer. Materials and Methods Eleven infants with umbilical artery catheters in place 1 to 2 cm above the diaphragm were selected for the study. In all instances, the arterial catheters were placed for clinical management of various illnesses.


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