Pulmonary hypertension (PH) is characterized by enhanced vasoreactivity and sustained pulmonary vasoconstriction, arising from aberrant Ca homeostasis in pulmonary arterial (PA) smooth muscle cells. In addition to Ca , magnesium, the most abundant intracellular divalent cation, also plays crucial roles in many cellular processes that regulate cardiovascular function. Recent findings suggest that magnesium regulates vascular functions by altering the vascular responses to vasodilator and vasoactive agonists and affects endothelial function by modulating endothelium-dependent vasodilatation in hypertension. Administration of magnesium also decreased pulmonary arterial pressure and improved cardiac output in animal models of PH. However, the role of magnesium in the regulation of pulmonary vascular function related to PH has not been studied. In this study, we examined the effects of magnesium on endothelin-1 (ET-1)-induced vasoconstriction, ACh-induced vasodilatation and the generation of NO in PAs of normoxic mice and chronic hypoxia (CH)-treated mice. Our data showed that removal of extracellular magnesium suppressed vasoreactivity of PAs to both ET-1 and ACh. A high concentration of magnesium (4.8 mm) inhibited ET-1-induced vasoconstriction in endothelium-intact or endothelium-disrupted PAs of normoxic and CH-treated mice, and enhanced the ACh-induced production of NO in PAs of normoxic mice. Moreover, magnesium enhanced ACh-induced vasodilatation in PAs of normoxic mice, and the enhancement was completely abolished after exposure to CH. Hence, in this study we demonstrated that increasing the magnesium concentration can attenuate the ET-1-induced contractile response and improve vasodilatation via release of NO from the endothelium. We also demonstrated that chronic exposure to hypoxia can cause endothelial dysfunction resulting in suppression of the magnesium-dependent modulation of vasodilatation.

Background: A low first-pass success rate of radial artery cannulation was obtained when using the conventional palpation technique(C-PT) or ultrasound-guided techniques, we therefore evaluate the effect of a modified long-axis in-plane ultrasound technique (M-LAINUT) in guiding radial artery cannulation in adults. Methods：We conducted a prospective, randomized and controlled clinical trial of 288 patients undergoing radial artery cannulation. Patients were randomized 1:1 to M-LAINUT or C-PT group at fujian medical university union hospital between 2017 and 2018. Radial artery cannulation was performed by three anesthesiologists with different experience. The outcome was the first and total radial artery cannulation success rates, the number of attempts and the cannulation time. Results: 285 patients were statistically analyzed. The success rate of first attempt was 91.6% in the M-LAINUT group (n=143) and 57.7% in the C-PT group (n=142; P<0.001) (odds ratio, 7.9; 95% confidence interval, 4.0-15.7). The total success rate (≤5 min and ≤3 attempts) in the M-LAINUT group was 97.9%, compared to 84.5% in the palpation group (p <0.001) (odds ratio, 8.5; 95% confidence interval, 2.5-29.2). The total cannulation time was shorter and the number of attempts was fewer in the M-LAINUT group than that in the C-PT group (p <0. 05). Conclusion: Modified long-axis in-plane ultrasound-guided radial artery cannulation can increase the first and total radial artery cannulation success rates, reduce the number of attempts and shorten the total cannulation time in adults.

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Using ETS-guided anesthesia and maintaining the sevoflurane concentration (0.7-1.3 MAC) can decrease the incidence of patient awareness during endoscopic surgery.

Background: A low first-pass success rate of radial artery cannulation was obtained when using the conventional palpation technique (C-PT) or conventional ultrasound-guided techniques, we; therefore, evaluate the effect of a modified long-axis in-plane ultrasound technique (M-LAINUT) in guiding radial artery cannulation in adults. Methods: We conducted a prospective, randomized and controlled clinical trial of 288 patients undergoing radial artery cannulation. Patients were randomized 1:1 to M-LAINUT or C-PT group at Fujian Medical University Union Hospital between 2017 and 2018. Radial artery cannulation was performed by 3 anesthesiologists with different experience. The outcome was the first and total radial artery cannulation success rates, the number of attempts and the cannulation time, and incidence of complications. Results: Two hundred eighty-five patients were statistically analyzed. The success rate of first attempt was 91.6% in the M-LAINUT group (n = 143) and 57.7% in the C-PT group (n = 142; P < .001) (odds ratio, 7.9; 95% confidence interval, 4.0–15.7). The total success rate (≤5 minutes and ≤3 attempts) in the M-LAINUT group was 97.9%, compared to 84.5% in the palpation group (P < .001) (odds ratio, 8.5; 95% confidence interval, 2.5–29.2). The total cannulation time was shorter and the number of attempts was fewer in the M-LAINUT group than that in the C-PT group (P < .05). The incidence of hematoma in the C-PT group was 19.7%, which was significantly higher than the 2.8% in the M-LAINUT group (P < .001). Conclusions: Modified long-axis in-plane ultrasound-guided radial artery cannulation can increase the first and total radial artery cannulation success rates, reduce the number of attempts, and shorten the total cannulation time in adults.

Increased extracellular magnesium concentration has been shown to attenuate the endothelin-1-induced contractile response via the release of nitric oxide (NO) from the endothelium in proximal pulmonary arteries (PAs) of chronic hypoxic mice. Here, we further examined the involvement of Mg 2+ in the inhibition of vasoconstriction in PAs and distal smaller pulmonary arteries (sPAs) in a monocrotaline-induced pulmonary arterial hypertension (MCT-PAH) rat model. The data showed that in control rats vasoconstriction in sPAs is more intense than that in PAs. In MCT-PAH rats, store-operated Ca 2+ entry (SOCE)-and receptor-operated Ca 2+ entry (ROCE)-mediated contraction were significantly strengthened. However, there was no upregulation of the vasoconstriction mediated by voltage-dependent calcium entry (VDCE). Furthermore, high magnesium greatly inhibited VDCE-mediated contraction in PAs rather than sPAs, which was the opposite of the ROCE-mediated contraction. Moreover, monocrotaline pretreatment partly eliminated the endothelium-dependent vasodilatation in PAs, which in sPAs, however, was still promoted by magnesium due to the increased NO release in pulmonary microvascular endothelial cells (PMVECs). In conclusion, the findings suggest that both SOCE-and ROCE-mediated vasoconstriction in the MCT-PAH model are enhanced, especially in sPAs. The inhibitory effect of high magnesium on vasoconstriction can be achieved partly by its direct role as a Ca 2+ antagonist and partly by increasing NO release in PMVECs.

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Objective To investigate the present situation of labour analgesia in comprehensive Grade 3A hospitals in Fujian Province, to analyse the influencing factors, and to seek countermeasures to promote the popularization of labour analgesia. Methods: The investigation was conducted at all Western medicine comprehensive Grade 3A hospitals in Fujian Province, field investigations and on-site questionnaire surveys were adopted, and on-site interviews were conducted with leaders in charge of the hospitals and leaders related to departments of labour analgesia. Results: Among the 16 hospitals surveyed, 12 hospitals (75%) routinely carried out intraspinal labour analgesia, and the analgesia rates for 2015, 2016, 2017 and 2018 were 0.24%, 1.43%, 2.34% and 9.21%, respectively. At present, the quantity of labour analgesia is insufficient, the proportion of analgesia is still low, and the enthusiasm of hospitals is not high. Factors affecting the development of labour analgesia mainly include a heavy workload/lack of staff (93.75%), department coordination/leadership (87.50%), high cost/low benefit (62.50%), maternal and family members (68.75%), and insufficient publicity (68.75%). Conclusions: The labour analgesia work of the comprehensive Grade 3A hospitals in Fujian Province is still in its initial stage; there is still a lack of uniform implementation standards and charging standards among hospitals in various cities. To better promote labour analgesia, it is suggested that hospitals increase the publicity of labour analgesia, strengthen the training of labour analgesia personnel, standardize the implementation standard of labour analgesia, set up appropriate charging items, and optimize labour analgesia management while appropriately supplementing medical personnel