Acute seizure activity in neonatal inflammation-sensitized hypoxia-ischemia in mice.

OBJECTIVE: To examine acute seizure activity and neuronal damage in a neonatal mouse model of inflammation-sensitized hypoxic-ischemic (IS-HI) brain injury utilizing continuous electroencephalography (cEEG) and neurohistology. METHODS: Neonatal mice were exposed to either IS-HI with Escherichia coli lipopolysaccharide (LPS) or HI alone on postnatal (p) day 10 using unilateral carotid artery ligation followed by global hypoxia (n = 10 [5 female, 5 male] for IS-HI, n = 12 [5 female, 7 male] for HI alone). Video cEEG was recorded for the duration of the experiment and analyzed for acute seizure activity and behavior. Brain tissue was stained and scored based on the degree of neuronal injury in the hippocampus, cortex, and thalamus. RESULTS: There was no significant difference in acute seizure activity among mice exposed to IS-HI compared to HI with regards to seizure duration (mean = 63 ± 6 seconds for HI vs mean 62 ± 5 seconds for IS-HI, p = 0.57) nor EEG background activity. Mice exposed to IS-HI had significantly more severe neural tissue damage at p30 as measured by neuropathologic scores (mean = 8 ± 1 vs 23 ± 3, p < 0.0001). INTERPRETATION: In a neonatal mouse model of IS-HI, there was no significant difference in acute seizure activity among mice exposed to IS-HI compared to HI. Mice exposed to IS-HI did show more severe neuropathologic damage at a later age, which may indicate the presence of chronic inflammatory mechanisms of brain injury distinct from acute seizure activity.

Decreased Cerebral Oxygenation in Premature Infants with Progressive Posthemorrhagic Ventricular Dilatation May Help with Timing of Intervention.

OBJECTIVE: The objective of this study was to determine the degree of progressive posthemorrhagic ventricular dilatation (PHVD) that is associated with a significant decrease in regional cerebral oxygen saturation (rScO2) in premature infants at risk for periventricular-intraventricular hemorrhage (PIVH). STUDY DESIGN: Cranial ultrasound (US) and near-infrared spectroscopy (NIRS) measurements of rScO2 were performed on inborn infants with birth weights less than 1,250 g on admission and at 1, 4, and 8 weeks of age. Infants with severe PIVH were studied weekly. A 1-hour average of rScO2 was compared with the frontal-occipital horn ratio (FOHR) measured the same day. Generalized linear models were used to analyze the relationship between FOHR and rScO2, by severity of PIVH, and adjusted for gestational age. Cut-off points of 0.55 for FOHR and 45% for rScO2 were used to calculate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The study cohort included 63 infants with normal US, 15 with grade-1 or -2 PIVH (mild group), and 21 with grade-3 or -4 PIVH (severe group). Increases in FOHR in the severe group were associated with decreases in rScO2 at 1 week (p = 0.036), 4 weeks (p = 0.013), and 8 weeks of life (p = 0.001) compared with the normal and mild groups. Infants with FOHR greater than 0.55 were 92% more likely to have rScO2 less than 45% when compared with infants with FOHR less than 0.55 (OR = 0.08, 95% CI: [0.04, 0.13], p < 0.001). CONCLUSION: Progressive PHVD (FOHR > 0.55) is a strong predictor of compromised cerebral oxygenation. A combination of rScO2 and FOHR measurements may aid in identifying infants with PHVD that would benefit from early intervention. KEY POINTS: · Earlier intervention in PHVD may improve outcomes.. · PHVD is diagnosed with US measurements of ventricular size.. · FOHR > 0.55 is associated with decreased cerebral perfusion..

Percutaneous Treatment of Multiple Recurrent Thromboembolization from a Descending Thoracic Aortic Intimal Sarcoma.

Aortic intimal sarcomas are rare tumors that may result in distal embolic ischemia. Here, we present a patient who presented with crescendo lower extremity and mesenteric ischemic events from malignant macroembolism. Management with percutaneous pharmacomechanical thromboembolectomy enabled restoration of distal perfusion and minimally invasive collection of tumor sample to confirm the suspected diagnosis of aortic sarcoma. The patient underwent definitive aortectomy and reconstruction and is recovering well.

Nonoperative Management of Traumatic Aortic Pseudoaneurysms.

BACKGROUND: Current blunt thoracic aortic injury (BTAI) guidelines recommend early repair of traumatic pseudoaneurysms (PSAs) due to risk for subsequent aortic rupture. Recent analyses indicate that early repair is required only in the setting of high-risk features, while delayed repair is safe and associated with lower morbidity and mortality in appropriately selected patients. To evaluate the appropriate indications for nonoperative management (NOM) of traumatic PSAs, we performed a systematic review of studies reporting outcomes for this management strategy. We hypothesized that NOM is safe in appropriately selected patients with traumatic aortic PSAs. METHODS: English language single- and multi-institutional series reporting NOM of traumatic thoracic aortic PSAs were identified by systematic literature search and review. A descriptive analysis was performed of NOM, with stratification by lesion size and patient follow-up. The primary outcomes were late aortic intervention, aortic-related death, and all-cause mortality. RESULTS: Eighteen studies, which included 937 patients with traumatic PSAs, were analyzed. One hundred ninety-one patients were managed nonoperatively. The primary indication for NOM was prohibitive risk for aortic repair due to severe comorbidities or concurrent injuries. Where reported, PSAs with <50% circumferential involvement accounted for 88% of lesions selected for NOM. Late interventions were required in 4% of patients. Inpatient aortic-related mortality was 2%, and all-cause inpatient mortality was 32%. Although survival at up to 4-7 years was reported, postdischarge follow-up after PSA NOM was limited to <1 year in most studies. CONCLUSIONS: NOM of traumatic aortic PSAs is a common practice in BTAI series reporting lesion-specific management, and is associated with low rates of treatment failure. These findings suggest that routine early repair may not be required for traumatic PSAs, particularly for lesions limited to <50% of the aortic circumference. Definitive repair can be delayed until patient stability and repair timing can be guided by assessment of lesion stability on follow-up imaging.