Total Intravenous Anesthesia Maintained the Degree of Pre-Existing Mitral Regurgitation Better than Isoflurane Anesthesia in Cardiac Surgery: A Randomized Controlled Trial

Neuroprotective effects of miR-142-5p downregulation against isoflurane-induced neurological impairment

Background

Isoflurane can lead to neuron damage to the developing brain, resulting in learning and memory disability. The aim of this study was to investigate the role of miR-142-5p on isoflurane-induced neurological impairment.

Methods

The Morris water maze (MWM) test was performed to evaluate spatial learning and memory of rats. The expression level of miR-142-5p was measured using qRT-PCR. MTT assay was used to calculate the viability of hippocampal neuronal cells. The cell apoptosis was analyzed using Flow cytometric assay.

Results

Isoflurane treatment led to the increase of neurological function score and escape latency, and the reduction of time spent in the original quadrant in rats. The expression level of miR-142-5p was increased significantly in isoflurane-treated rats. MiR-142-5p downregulation protected against isoflurane-induced neurological impairment, which was reflected by the decrease of neurological function score and escape latency, and the increase of time spent in the original quadrant. In vitro, downregulation of miR-142-5p alleviated isoflurane-induced neuron cell viability inhibition, and relieved isoflurane-induced cell apoptosis.

Conclusions

MiR-142-5p downregulation plays a neuroprotective role in protecting against isoflurane-induced neurological impairment through regulating neuron cell viability and apoptosis. It provides a theoretical basis for the investigation of the mechanism underlying the effect on isoflurane-induced neurological impairment.

Systemic Oxygen Delivery during One-Lung Ventilation: Comparison between Propofol and Sevoflurane Anaesthesia in a Randomised Controlled Trial

Systemic oxygen delivery (DO₂) is a more comprehensive marker of patient status than arterial oxygen saturation (SaO₂), and DO₂ in the range of 330–500 mL min⁻¹ is reportedly adequate during anaesthesia. We measured DO₂ during one-lung ventilation (OLV) for thoracic surgery—where the risk of pulmonary shunt is significant, and hypoxia occurs frequently—and compared sevoflurane and propofol, the two most commonly used anaesthetics in terms of DO₂. Sevoflurane impairs hypoxic pulmonary vasoconstriction. Thus, our hypothesis was that propofol-based anaesthesia would show a higher DO₂ value than sevoflurane-based anaesthesia. This was a double-blinded randomised controlled trial conducted at a university hospital from 2017 to 2018. The study population consisted of patients scheduled for lobectomy under OLV (N = 120). Sevoflurane or propofol was titrated to a bispectral index of 40–50. Haemodynamic variables were measured during two-lung ventilation (TLV) and OLV at 15 and 45 min (OLV15 and OLV45, respectively) using oesophageal Doppler monitoring. The mean DO₂ (mL min⁻¹) was not different between the sevoflurane and propofol anaesthesia groups (TLV: 680 vs. 706; OLV15: 685 vs. 703; OLV45: 759 vs. 782, respectively). SaO₂ was not correlated with DO₂ (r = 0.09, p = 0.100). Patients with SaO₂ < 94% showed adequate DO₂ (641 ± 203 mL min⁻¹), and patients with high SaO₂ (> 97%) showed inadequate DO₂ (14% of measurements < 500 mL min⁻¹). In conclusion, DO₂ did not significantly differ between sevoflurane and propofol. SaO₂ was not correlated with DO₂ and was not informative regarding whether the patients were receiving an adequate oxygen supply. DO₂ may provide additional information on patient status, which may be especially important when patients show a low SaO₂.