Article

Haemoglobin oxygen saturation is a determinant of cerebral artery blood flow velocity in children with sickle cell anaemia.

Hematology-Oncology, Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX 75390-9063, USA.
British Journal of Haematology (Impact Factor: 4.96). 04/2009; 145(4):500-5. DOI: 10.1111/j.1365-2141.2009.07652.x
Source: PubMed

ABSTRACT Steady-state haemoglobin (Hb) desaturation is a common finding in sickle cell anaemia (Hb SS) that could predispose to stroke by limiting oxygen delivery to the brain. To determine its association with the risk of overt stroke, we examined the relationship between daytime Hb saturation measured by pulse oximetry (SpO(2)) and cerebral artery blood flow velocity measured by transcranial Doppler ultrasonography (TCD), an established risk factor for overt stroke in Hb SS. We studied 181 children using multivariate models to control for known determinants of TCD velocity, including age, haematocrit, and a measure of stenosis. We found that SpO(2) correlated significantly and inversely with TCD velocity in both the right and left middle cerebral arteries. Hb desaturation was associated with increased cerebral artery blood flow velocities and increased odds of abnormal TCD velocities, hence increased risk of stroke. About 5% of the variation in TCD velocity could be ascribed to Hb saturation while controlling for other determinants of TCD velocity. In conclusion, Hb saturation is a determinant of TCD velocity and a risk factor for stroke in children with Hb SS.

0 Followers
 · 
63 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: New Findings• What is the central question of this study? Autonomic nervous dysfunction is implicated in complications of sickle cell anaemia (SCA). In healthy adults, a deep inspiratory breath hold (IBH) elicits rapid transient SNS‐ mediated vasoconstriction detectable using Laser Doppler Flux (LDF) assessment of the finger‐tip cutaneous micovasculature. • What is the main finding and its importance? We demonstrate significantly increased resting peripheral blood flow and sympathetic activity in African children with SCA compared to sibling controls and increased sympathetic stimulation in response to vasoprovocation with DIG.This study is the first to observe an inverse association between resting peripheral blood flow and haemoglobin oxygen saturation (SpO2). These phenomena may be an adaptive response to the hypoxic exposure in SCA.
    Experimental Physiology 01/2013; 98(1). DOI:10.1113/expphysiol.2011.064055 · 2.87 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Sleep-related disorders (SRDs) are common in sickle cell disease, however, identification may be time-consuming. Simultaneous survey of multiple SRDs utilizing a simplified instrument would facilitate screening. A simplified questionnaire investigating SRDs [sleep-disordered breathing (SDB), restless legs syndrome (RLS), insomnia, parasomnias, and daytime effects of disrupted sleep] was administered to 2–18-year-old children with sickle cell disease. One hundred participants completed this 5–7 minute survey without difficulties: 54 awoke unrefreshed, 41 had short-term insomnia, 30 had sleep-maintenance insomnia, 21 had chronic sleep-onset insomnia, 54 had chronic habitual snoring and 11 met the criteria for RLS. Sleep-maintenance insomnia was associated with increased body mass index (BMI) (p = 0.001), and chronic sleep-onset insomnia was associated with higher hemoglobin (Hb) levels (p = 0.04). Survey-reported symptoms of SRDs were significantly higher than that reported in the general pediatric population. A fast and simplified SRD survey is feasible and suggests a high prevalence of SRDs in children with sickle cell disease.
    Hemoglobin 05/2014; 38(4). DOI:10.3109/03630269.2014.919941 · 0.96 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective To identify risk factors for headache and migraine in children with sickle cell disease and test the hypothesis that either or both are independently associated with silent cerebral infarcts. Study design In this cross-sectional study, we evaluated the health history, laboratory values, and brain magnetic resonance imaging findings of participants with sickle cell disease (hemoglobinSS or hemoglobinSβ°-thalassemia) with no history of overt stroke or seizures. Participants characterized headache severity and quality. Migraine was defined by International Headache Society criteria modified for increased sensitivity in children. Neuroradiology and neurology committees adjudicated the presence of silent cerebral infarction by review of magnetic resonance imaging and standardized examination by pediatric neurologists. Results The cohort included 872 children (51.1% males), ranging in age from 5 to 15 years (mean age, 9.1 years). Of these children, 317 (36.4%) reported recurrent headaches, and 132 (15.1%) reported migraines. In multivariable logistic regression analyses, both were associated with lower steady-state hemoglobin (P = .01 for headaches; P < .01 for migraines) and higher pain rate (P < .01 for headaches; P < .01 for migraines), defined as the number of admissions requiring opioids in the previous 3 years. The presence of silent cerebral infarction was not associated with recurrent headaches or migraines. Only 1.9% (6 of 317) of children with recurrent headaches received medication for headache prophylaxis. Conclusion Recurrent headaches and migraines are common and undertreated in children with sickle cell disease. Low hemoglobin levels and high pain rates are associated with recurrent headaches and migraines; whereas, silent cerebral infarction is not.
    The Journal of pediatrics 05/2014; 164(5). DOI:10.1016/j.jpeds.2014.01.001 · 3.74 Impact Factor

Full-text

Download
18 Downloads
Available from
May 20, 2014