Safety and efficacy of therapeutic hypothermia in neonates with mild hypoxic-ischemic encephalopathy

Hypoxia-preconditioned human dental pulp stem cells transplantation alleviates hypoxic-ischemic brain damage via STAT3/NLRP3/Caspase-1 axis in neonatal rats

This study was conducted to examine the effects and mechanisms of hypoxia-preconditioned human dental pulp stem cells (H-hDPSCs) transplantation on microglial pyroptosis in neonatal rats with hypoxic-ischemic brain damage (HIBD). The hDPSCs were extracted using the tissue block method and identified by immunofluorescence staining. The HIBD model was constructed using the classical Rice-Vannucci method. 24 h after HIBD, normoxic preconditioning hDPSCs (N-hDPSCs) and H-hDPSCs were transplanted into the lateral ventricle. The brain damage was examined by hematoxylin & eosin and Nissl stainings 72 h after transplantation. The expression of signal transducer and activator of transcription 3 (STAT3)/NOD-like receptor family pyrin domain-containing 3 (NLRP3)/Caspase-1 axis-related proteins was analyzed by immunofluorescence staining and western blots. Tissue levels of interleukin-1 beta (IL-1β) were derived from ELISA. After modeling, the neural cells in the HIBD group were disordered and sparsely scattered, with a deficiency of nitrosamines. The data revealed that the phosphorylated STAT3, NLRP3, Cleaved-Caspase 1, N-terminal fragment of gasdermin D (GSDMD-N), and IL-1β protein expression were significantly lower in the H-hDPSCs and N-hDPSCs groups compared to the HIBD group. The protein expression in the H-hDPSCs group was considerably lower than in the N-hDPSCs group. H-hDPSCs may protect microglia from pyroptosis by regulating the STAT3/NLRP3/Caspase-1/GSDMD axis to alleviate inflammatory damage, and attenuate HIBD in newborn rats at the same time. Moreover, the therapeutic effect of H-hDPSCs transplantation was superior to that of N-hDPSCs transplantation.

[Efficacy of therapeutic hypothermia on mild neonatal hypoxic-ischemic encephalopathy: a prospective randomized controlled study]

OBJECTIVES

To investigate the efficacy of therapeutic hypothermia on mild neonatal hypoxic-ischemic encephalopathy (HIE).

METHODS

A prospective study was performed on 153 neonates with mild HIE who were born from September 2019 to September 2023. These neonates were randomly divided into two groups: therapeutic hypothermia (n=77) and non-therapeutic hypothermia group (n=76). The short-term clinical efficacy of the two groups were compared. Barkovich scoring system was used to analyze the severity of brain injury shown on magnetic resonance imaging (MRI) between the two groups.

RESULTS

There were no significant differences in gestational age, gender, birth weight, mode of birth, and Apgar score between the therapeutic hypothermia and non-therapeutic hypothermia groups (P>0.05). There were no significant differences in the incidence rates of sepsis, arrhythmia, persistent pulmonary hypertension and pulmonary hemorrhage and the duration of mechanical ventilation within the first 72 hours after birth between the two groups. The therapeutic hypothermia group had longer prothrombin time within the first 72 hours after birth and a longer hospital stay (P<0.05). Compared with the non-therapeutic hypothermia group, the therapeutic hypothermia group had lower incidence rates of MRI abnormalities (30% vs 57%), moderate to severe brain injury on MRI (5% vs 28%), and watershed injury (27% vs 51%) (P<0.05), as well as lower medium watershed injury score (0 vs 1) (P<0.05).

CONCLUSIONS

Therapeutic hypothermia can reduce the incidence rates of MRI abnormalities and watershed injury, without obvious adverse effects, in neonates with mild HIE, suggesting that therapeutic hypothermia may be beneficial in neuroprotection in these neonates.

Targeted Temperature Management for Poor Grade Aneurysmal Subarachnoid Hemorrhage: A Pilot Study

OBJECTIVE

We assessed the effectiveness and safety of target temperature management (TTM) in treating patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH). The primary objective was to evaluate the neurological outcome at 3 months. Secondary objectives were to assess mortality, delayed cerebral ischemia, cerebral edema, hydrocephalus, midline shift, and laboratory indicators related to TTM.

METHODS

A single-blind, nonrandomized controlled trial was conducted. After admission, patients with poor-grade aSAH (Hunt-Hess scores IV ∼ V) were assigned to a TTM group or a control group in a 1:1 ratio. TTM with core temperatures ranging from 36°C to 37°C was performed immediately and maintained until microclipping or endovascular embolization. Subsequently, rapid induction to 33°C ∼ 35°C was carried out and maintained for 3 to 5 days. Then, the patients underwent slow rewarming to 36°C ∼ 37°C and maintained at that temperature for a minimum of 48 hours.

RESULTS

Sixty patients (30 treated with TTM and 30 with standard treatment) were included in the study. At 3 months, a favorable prognosis (modified Rankin scale score 0 to 3) was significantly higher in the TTM group than in the control group (n = 14, 46.7% vs. n = 6, 20.0%, P = 0.028). Adjusted multivariate logistics regression analysis indicated that TTM (odds ratio = 0.20, 95% confidence interval: 0.05-0.77, P = 0.019) reduced the number of unfavorable prognoses 3 months after admission.

CONCLUSIONS

This study demonstrated the effectiveness and safety of TTM in patients with poor-grade aSAH, and its implementation improved neurological outcomes. Multicenter randomized controlled studies with a large number of patients are needed to confirm these observations.