Cerebral Sinovenous Thrombosis in the Asphyxiated Cooled Infants: A Prospective Observational Study

Association between Portal Vein Thrombosis after Umbilical Vein Catheterization and Neonatal Asphyxia

INTRODUCTION

Neonatal portal vein thrombosis (PVT) is frequently related to umbilical venous catheterization (UVC), but risk factors remain unclear. This study aims to analyze the variables associated to PVT in near- to full-term newborns with UVC, with a focus on newborns exposed to controlled therapeutic hypothermia (CTH) for hypoxic ischemic encephalopathy (HIE).

METHODS

This is retrospective cohort study of infants delivered at or after 36 weeks and with a birthweight over 1,500 g. All infants were assessed for UVC location and PVT using ultrasonography performed between day 5 and day 10 after catheterization.

RESULTS

Among 213 eligible patients, PVT was diagnosed in 57 (27%); among them, 54 (95%) were localized in the left portal vein branch. With all significant factors in univariate analysis considered, higher gestational age at birth (adjusted OR 1.35; 95% CI: 1.12-1.64, p = 0.002) and duration of UVC placement (adjusted OR 1.36; 95% CI: 1.11-1.67, p = 0.004) were the main risk factors of PVT. Among 87 infants who were cooled for HIE, 31 (36%) had PVT compared to 26 (21%) in infants without CTH. Using a multivariate model including variables linked to treatment procedures only, an increased PVT incidence was statistically associated with UVC duration (adjusted OR 1.33; 95% CI: 1.08; 1.63, p = 0.01) and CTH (adjusted OR 1.94; 95% CI: 1.04-3.65, p = 0.04).

CONCLUSION

Left PVT was frequently observed in near- to full-term neonates with UVC. Among factors linked to treatment procedures, both duration of UVC and CTH exposure for HIE were found to be independent risk factors of PVT.

Analgesia and sedation strategies in neonates undergoing whole-body therapeutic hypothermia: A scoping review

BACKGROUND

Therapeutic hypothermia (TH) is a widely practiced neuroprotective strategy for neonates with hypoxic-ischemic encephalopathy. Induced hypothermia is associated with shivering, cold pain, agitation, and distress.

OBJECTIVE

This scoping review determines the breadth of research undertaken for pain and stress management in neonates undergoing hypothermia therapy, the pharmacokinetics of analgesic and sedative medications during hypothermia and the effect of such medication on short- and long-term neurological outcomes.

METHODS

We searched the following online databases namely, (i) MEDLINE, (ii) Web of Science, (iii) Cochrane Library, (iv) Scopus, (v) CINAHL, and (vi) EMBASE to identify published original articles between January 2005 and December 2022. We included only English full-text articles on neonates treated with TH and reported the sedation/analgesia strategy used. We excluded articles that reported TH on transport or extracorporeal membrane oxygenation, did not report the intervention strategies for sedation/analgesia, and reported hypoxic-ischemic encephalopathy in which hypothermia was not applied.

RESULTS

The eligible publications (n = 97) included cohort studies (n = 72), non-randomized experimental studies (n = 2), pharmacokinetic studies (n = 4), dose escalation feasibility trial (n = 1), cross-sectional surveys (n = 5), and randomized control trials (n = 13). Neonatal Pain, Agitation, and Sedation Scale (NPASS) is the most frequently used pain assessment tool in this cohort. The most frequently used pharmacological agents are opioids (Morphine, Fentanyl), benzodiazepine (Midazolam) and Alpha2 agonists (Dexmedetomidine). The proportion of neonates receiving routine sedation-analgesia during TH is center-specific and varies from 40-100% worldwide. TH alters most drugs' metabolic rate and clearance, except for Midazolam. Dexmedetomidine has additional benefits of thermal tolerance, neuroprotection, faster recovery, and less likelihood of seizures. There is a wide inter-individual variability in serum drug levels due to the impact of temperature, end-organ dysfunction, postnatal age, and body weight on drug metabolism.

CONCLUSIONS

No multidimensional pain scale has been tested for reliability and construct validity in hypothermic encephalopathic neonates. There is an increasing trend towards using routine sedation/analgesia during TH worldwide. Wide variability in the type of medication used, administration (bolus versus infusion), and dose ranges used emphasizes the urgent need for standardized practice recommendations and guidelines. There is insufficient data on the long-term neurological outcomes of exposure to these medications, adjusted for underlying brain injury and severity of encephalopathy. Future studies will need to develop framework tools to enable precise control of sedation/analgesia drug exposure customized to individual patient needs.

Magnetic resonance venography to evaluate cerebral sinovenous thrombosis in infants receiving therapeutic hypothermia

BACKGROUND

The incidence of cerebral sinovenous thrombosis (CSVT) in infants receiving therapeutic hypothermia for neonatal encephalopathy remains controversial. The aim of this study was to identify if the routine use of magnetic resonance venography (MRV) in term-born infants receiving hypothermia is associated with diagnostic identification of CSVT.

METHODS

We performed a retrospective review of 291 infants who received therapeutic hypothermia from January 2014 to March 2020. Demographic and clinical data, as well as the incidence of CSVT, were compared between infants born before and after adding routine MRV to post-rewarming magnetic resonance imaging (MRI).

RESULTS

Before routine inclusion of MRV, 209 babies were cooled, and 25 (12%) underwent MRV. Only one baby (0.5%) was diagnosed with CSVT in that period, and it was detected by structural MRI, then confirmed with MRV. After the inclusion of routine MRV, 82 infants were cooled. Of these, 74 (90%) had MRV and none were diagnosed with CSVT.

CONCLUSION

CSVT is uncommon in our cohort of infants receiving therapeutic hypothermia for neonatal encephalopathy. Inclusion of routine MRV in the post-rewarming imaging protocol was not associated with increased detection of CSVT in this population.

IMPACT

Cerebral sinovenous thrombosis (CSVT) in infants with NE receiving TH may not be as common as previously indicated. The addition of MRV to routine post-rewarming imaging protocol did not lead to increased detection of CSVT in infants with NE. Asymmetry on MRV of the transverse sinus is a common anatomic variant. MRI alone may be sufficient in indicating the presence of CSVT.

Neonatal Cerebral Sinovenous Thrombosis Post–Therapeutic Hypothermia in Perinatal Asphyxia: A Case Report

Cerebral sinovenous thrombosis (CSVT) is an uncommon condition in neonates and often leads to adverse neurodevelopmental outcomes. A high index of suspicion for CSVT is mandated for asphyxiated infants, especially following therapeutic hypothermia (TH). Magnetic resonance venography can assist in the early detection of CSVT in suspected cases. Timely initiation of anticoagulation therapy prevents thrombus propagation and allows recanalization at around 6 to 12 weeks. Long-term follow-up is essential as cognitive impairment, motor dysfunctions, and epilepsy are common complications. Herein, we describe the clinical course of a term infant who developed CSVT in the first week of life following TH for perinatal asphyxia, its management strategies, and short-term follow-up till infancy.

Cerebral Sinovenous Thrombosis in Infants and Children: A Practical Approach to Management

Cerebral sinovenous thrombosis (CSVT) is a rare, yet potentially devastating disorder, associated with acute complications and long-term neurologic sequelae. Consensus-based international pediatric CSVT treatment guidelines emphasize early clinical-radiologic recognition and prompt consideration for anticoagulation therapy. However, lack of clinical trials has precluded evidence-based patient selection, anticoagulant choice, optimal monitoring parameters and treatment duration. Consequently, uncertainties and controversies persist regarding anticoagulation practices in pediatric CSVT. This review focuses on commonly encountered issues that continue to pose questions and raise debates regarding anticoagulation therapy among pediatric neurologists and hematologists.

Magnetic Resonance Imaging in (Near-)Term Infants with Hypoxic-Ischemic Encephalopathy

Hypoxic-ischemic encephalopathy (HIE) is a major cause of neurological sequelae in (near-)term newborns. Despite the use of therapeutic hypothermia, a significant number of newborns still experience impaired neurodevelopment. Neuroimaging is the standard of care in infants with HIE to determine the timing and nature of the injury, guide further treatment decisions, and predict neurodevelopmental outcomes. Cranial ultrasonography is a helpful noninvasive tool to assess the brain before initiation of hypothermia to look for abnormalities suggestive of HIE mimics or antenatal onset of injury. Magnetic resonance imaging (MRI) which includes diffusion-weighted imaging has, however, become the gold standard to assess brain injury in infants with HIE, and has an excellent prognostic utility. Magnetic resonance spectroscopy provides complementary metabolic information and has also been shown to be a reliable prognostic biomarker. Advanced imaging modalities, including diffusion tensor imaging and arterial spin labeling, are increasingly being used to gain further information about the etiology and prognosis of brain injury. Over the past decades, tremendous progress has been made in the field of neonatal neuroimaging. In this review, the main brain injury patterns of infants with HIE, the application of conventional and advanced MRI techniques in these newborns, and HIE mimics, will be described.

Neonatal encephalopathy: Etiologies other than hypoxic-ischemic encephalopathy

Neonatal encephalopathy (NE) describes the clinical syndrome of a newborn with abnormal brain function that may result from a variety of etiologies. HIE should be distinguished from neonatal encephalopathy due to other causes using data gathered from the history, physical and neurological exam, and further investigations. Identifying the underlying cause of encephalopathy has important treatment implications. This review outlines conditions that cause NE and may be mistaken for HIE, along with their distinguishing clinical features, pathophysiology, investigations, and treatments. NE due to brain malformations, vascular causes, neuromuscular causes, genetic conditions, neurogenetic disorders and inborn errors of metabolism, central nervous system (CNS) and systemic infections, and toxic/metabolic disturbances are discussed.

Research advances in neonatal cerebral sinovenous thrombosis

Neonatal cerebral sinovenous thrombosis (CSVT) is a cerebrovascular disease with a seriously underestimated incidence rate. Due to a lack of specific clinical manifestations and the low sensitivity of conventional imaging examinations, it has long been considered a rare disease in neonates. In recent years, the development of magnetic resonance technology has improved the diagnostic rate of CSVT. This article reviews the research advances in intracranial venous anatomy of neonates and clinical manifestations, imaging features, treatment, and prognosis of CSVT and deep venous thrombosis, in order to improve the understanding and to make correct diagnosis and treatment of neonatal CSVT.

Clinical Profile and Long-Term Outcome in Neonatal Cerebral Sinus Venous Thrombosis

BACKGROUND

Neonatal cerebral sinus venous thrombosis (CSVT) causes high morbidity and mortality. Factors associated with either favorable or unfavorable long-term outcomes have not been clearly established. This study aimed to determine the factors involved in long-term neurological outcomes in patients with neonatal CSVT.

METHODS

This was a retrospective cohort study of patients with neonatal CSVT at a single institution. Clinical factors associated with long-term neurological outcomes were examined.

RESULTS

A total of 67 patients met study inclusion criteria for radiologically confirmed neonatal CSVT. The mean patient follow-up duration was four years (range one week to 16 years, median six years). We observed a favorable neurological outcome defined by a pediatric stroke outcome measures (PSOM) score of 0 to 0.5 in 26 (53%) of osurviving patients at follow-up. An unfavorable neurological outcome as defined by PSOM score >0.5 was observed in 23 survivors (47%). Death was reported in 18 (27%) patients, of which 10 patients died due to direct complications of CSVT. Congential heart disease and genetic disease were associated with significantly increased odds for all-cause death. Cardiorespiratory failure and altered mental status during the initial neurological examination were significantly associated with increased odds of death due to CSVT. Among surviving patients, higher PSOM scores were associated with premature birth (i.e., gestational age < 37 weeks), traumatic birth, site of thrombosis in the straight sinus, site of thrombosis in the internal cerebral veins, and hemorrhagic infarct. In contrast, lower PSOM scores were associated with a normal neurological examination at presentation, thrombosis in only superficial sinuses, and hemorrhage without infarct. There was no statistically significant association between the type and duration of CSVT treatment.

CONCLUSIONS

The major factors influencing outcome of neonates following CSVT included comorbid medical conditions, abnormal neurological examination at presentation, location of venous thrombosis, and type of cerebral injury. These results can help guide further studies in neonatal CSVT aiming to decrease morbidity and mortality with the goal of improving long-term neurological outcomes.

Venous thrombosis in neonates

The incidence of thrombotic disorders in neonates and children is increasing with advances in diagnostic modalities, supportive care, and management of many health conditions. The developing coagulation system, need for intensive care, including catheterization, and co-morbid conditions are responsible for the relatively high risk of thrombosis in neonates compared to older children. This review addresses the advances over the last 3 years in neonatal thrombosis, with a focus on epidemiology, cerebral sinovenous thrombosis (CSVT), renal vein thrombosis (RVT), and portal vein thrombosis (PVT). The incidence of neonatal thrombosis in the contemporary era is reported to be 6.9-15 per 1,000 neonatal intensive care unit (NICU) admissions, compared to 2.4 per 1,000 NICU admissions reported in older registry data. The majority of recently published studies are small, retrospective, and from single centers, albeit they emphasize the need for definitive data to support the efficacy and safety of anticoagulation therapy (ACT) in the management of CSVT, RVT, and PVT. We highlight two important international initiatives geared towards improving the evidence base for these conditions. The International Pediatric Thrombosis Network (IPTN) is a collaboration of 74 centers across 27 countries (as of January 2021) which has started important projects like the international neonatal RVT registry, while the International Pediatric Stroke Study (IPSS) group is in the planning stages of a randomized controlled trial to evaluate the utility of ACT in the management of neonatal CSVT.

Clinical Diversity of Cerebral Sinovenous Thrombosis and Arterial Ischaemic Stroke in the Neonate: A Surveillance Study

INTRODUCTION

Incidence, risk factors, clinical presentation, onset of symptoms, and age at diagnosis differ between neonatal arterial ischaemic stroke (AIS) and cerebral sinovenous thrombosis (CSVT). A more accurate and earlier discrimination of these two entities can be of eminent importance.

METHODS

Active surveillance for AIS and CSVT was performed in 345 German paediatric hospitals. Only MRI confirmed cases were included in our analysis. Patients with AIS were compared to CSVT cases with regard to age at diagnosis, pattern of clinical symptoms, and case characteristics.

RESULTS

Data on 144 AIS and 51 CSVT neonatal cases were collected from 2015 to 2017. The frequency of reported AIS cases was 2.8 [95% CI 2.1; 3.9] times higher compared to reported CSVT cases. CSVT patients were more likely to be born premature (CSVT 14/48, 29.2%; AIS 19/140, 13.2%; p = 0.02) and to have signs of perinatal acidosis (30.2% CSVT vs. 13.5% AIS; p = 0.01). Generalized seizures and lethargy were more likely to occur in infants with CSVT (p < 0.0001). Age at onset of symptoms and at time of diagnosis were shifted to older ages in CSVT (p < 0.0001).

DISCUSSION/CONCLUSION

In the neonatal period, AIS is about three times more common than CSVT. A higher proportion of critically ill infants in CSVT and a later onset of symptoms may indicate that perinatal and postnatal complications are more important for CSVT than for AIS.

Epidemiology and outcomes of clinically unsuspected venous thromboembolism in children: A systematic review

BACKGROUND

Clinically unsuspected venous thromboembolic events (uVTE) detected during routine imaging pose a management challenge due to limited knowledge about their clinical significance. Unsuspected VTE are often referred as "asymptomatic," "incidental," or "clinically silent/occult" VTE.

OBJECTIVE

To understand the epidemiology, management, and outcomes of uVTE in children.

METHODS

A systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The search criteria included controlled vocabulary and keywords for VTE, incidental findings, and children (ages ≤ 21 years).

RESULTS

Among 10 875 articles, 51 studies (8354 children with 758 uVTE) were selected. The studies were heterogeneous, I2 96%; P < .0001. Unsuspected VTE were diagnosed in two settings: first, asymptomatic VTE (aVTE) diagnosed through surveillance imaging for VTE (46 studies; n = 5894; aVTE: 715, pooled frequency: 19%, 95% confidence interval [CI]: 13%-24%); second, incidental VTE (iVTE) diagnosed during imaging performed for indications without primary suspicion for VTE (6 studies; n = 2460; iVTE: 43). The majority (94%) of aVTE were associated with central venous lines (CVL). Non-CVL settings included post-spinal surgery, post-splenectomy, trauma, nephrotic syndrome, and newborns. In general, aVTE were reported to have a benign clinical course, were mostly transient, and resolved without intervention and with few immediate or long-term functional complications. Incidental VTE were primarily detected in children with cancer and ranged from tumor-associated thrombi to pulmonary embolism (PE) with insufficient evidence to draw meaningful conclusions about their management.

CONCLUSION

Clinically uVTE were predominantly diagnosed with CVL and their outcomes were generally favorable implying limited benefit of routine surveillance and thromboprophylaxis. Prospective research is needed to clarify the optimal management of iVTE.

Management of Multi Organ Dysfunction in Neonatal Encephalopathy

Neonatal Encephalopathy (NE) describes neonates with disturbed neurological function in the first post-natal days of life. NE is an overall term that does not specify the etiology of the encephalopathy although it often involves hypoxia-ischaemia. In NE, although neurological dysfunction is part of the injury and is most predictive of long-term outcome, these infants may also have multiorgan injury and compromise, which further contribute to neurological impairment and long-term morbidities. Therapeutic hypothermia (TH) is the standard of care for moderate to severe NE. Infants with NE may have co-existing immune, respiratory, endocrine, renal, hepatic, and cardiac dysfunction that require individualized management and can be impacted by TH. Non-neurological organ dysfunction not only has a negative effect on long term outcome but may also influence the efficacy of treatments in the acute phase. Post resuscitative care involves stabilization and decisions regarding TH and management of multi-organ dysfunction. This management includes detailed neurological assessment, cardio-respiratory stabilization, glycaemic and fluid control, sepsis evaluation and antibiotics, seizure identification, and monitoring and responding to biochemical and coagulation derangements. The emergence of new biomarkers of specific organ injury may have predictive value and improve the definition of organ injury and prognosis. Further evidence-based research is needed to optimize management of NE, prevent further organ dysfunction and reduce neurodevelopmental impairment.

Perinatal Stroke

Perinatal strokes are a diverse but specific group of focal cerebrovascular injuries that occur early in brain development and affect an estimated 5 million people worldwide. The objective of this review is to describe the epidemiology, clinical presentations, pathophysiology, outcomes, and management for the 6 subtypes of perinatal stroke. Some perinatal strokes are symptomatic in the first days of life, typically with seizures, including neonatal arterial ischemic stroke, neonatal hemorrhagic stroke, and cerebral sinovenous thrombosis. The remaining subtypes present in the first year of life or later, usually with motor asymmetry and include arterial presumed perinatal ischemic stroke, presumed perinatal hemorrhagic stroke, and in utero periventricular venous infarction. The consequences of these injuries include cerebral palsy, epilepsy, and cognitive and behavioral challenges, in addition to the psychosocial impact on families. While there have been significant advances in understanding mechanisms of both injury and recovery, there is still a great deal to learn regarding causation and the optimization of outcomes.

Neonatal cerebral sinovenous thrombosis

Cerebral sinovenous thrombosis (CSVT) is a focal or diffuse disruption of cerebral blood flow secondary to occlusion of cerebral veins and/or sinuses. The challenge of CSVT during the neonatal age has led to a great interest in this condition among neonatologists, child neurologists, and pediatric neuroradiologists. The highly variable clinical spectra, etiologies, and prognosis require fine medical skills and a high level of suspicion. Nevertheless, the diagnosis is often delayed or missed altogether. Differences in brain vulnerability at different stages of maturation may explain the spectrum of associated brain lesions, which varies with gestational age. Treatment is controversial and reported clinical outcomes vary widely. The controversial treatment of CSVT with anticoagulant therapy is based only on case series and expert consensus, there is lack of safety data.