Analysis of clinical application effects and challenges of early warning system for the high-risk obstetric women of China: A scoping review.

BACKGROUND: Obstetric critical illness is an important factor that leads to an increase in maternal mortality. Early warning assessment can effectively reduce maternal and neonatal mortality and morbidity. However, there are multiple early warning systems, and the effect and applicability of each system in China still need to be explored. OBJECTIVES: To elaborate on the application, effectiveness and challenges of the existing early warning systems for high-risk obstetric women in China and to provide a reference for clinical practice. DESIGN: A scoping review guided by the Arksey and O'Malley framework and reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for scoping review (PRISMA-ScR) guidelines. ELIGIBILITY CRITERIA: We included original studies related to early warning and excluded those that were guidelines, consensus and reviews. The included studies were published in Chinese or English by Chinese scholars as of June 2021. DATA SOURCES: CNKI, Wanfang, VIP, Cochrane, CINAHL, Embase, PubMed and Web of Science databases were searched systematically, and the reference sections of the included papers were snowballed. RESULTS: In total, 598 articles were identified. These articles were further refined using keyword searches and exclusion criteria, and 17 articles met the inclusion criteria. We extracted data related to each study's population, methods and results. Early warning tools, outcome indices, effects and challenges are discussed. CONCLUSIONS: Although all studies have shown that early warning systems have good application effects, the use of early warning systems in China is still limited, with poor regional management and poor sensitivity for specific obstetric women. Future research needs to develop more targeted early warning tools for high-risk obstetric women and address the current challenges in clinical applications.

Effect of low-dose ketamine on MACBAR of sevoflurane in laparoscopic cholecystectomy: A randomized controlled trial.

WHAT IS KNOWN AND OBJECTIVE: Low-dose ketamine can reduce the minimum alveolar concentration of sevoflurane necessary to block the adrenergic response (MACBAR ) in animals. However, the effects of low-dose ketamine on the sevoflurane MACBAR in patients undergoing laparoscopic surgery are unclear. The aim of this study was to investigate the effects of three different low doses of ketamine on the MACBAR of sevoflurane in patients undergoing laparoscopic cholecystectomy. METHODS: One hundred patients who underwent laparoscopic cholecystectomy were enrolled. After general anaesthesia induction and tracheal intubation, patients received sevoflurane anaesthesia in combination with a loading dose of saline followed by infusion or a loading dose of 0.5 mg/kg ketamine followed by a continuous infusion of 5 (K1 group), 10 (K2 group) and 20 µg/kg/min (K3 group). The target concentration of end-tidal sevoflurane was maintained for at least 20 minutes before carbon dioxide pneumoperitoneum stimulus. The MACBAR of sevoflurane in each group was determined by using an up-and-down sequential allocation technique. RESULTS AND DISCUSSION: Seventy-one patients completed the study. The values of MACBAR for sevoflurane were 5.3% in the K0 , 4.8% in K1 , 3.3% in K2 and 3.2% in K3 groups. The use of ketamine significantly reduced the MACBAR of sevoflurane compared to sevoflurane alone. The K2 and K3 groups showed significantly lower values of MACBAR than that in the K1 group. However, a higher dose of ketamine in the K3 group did not further reduce the sevoflurane MACBAR . The mean arterial blood pressure (MAP) values before pneumoperitoneum in the K2 and the K3 groups were significantly higher compared to those in the K0 and K1 groups. Compared with the values before pneumoperitoneum, the heart rate and MAP after pneumoperitoneum were significantly increased. Overall, the haemodynamics remained stable during the study period in all groups. WHAT IS NEW AND CONCLUSION: A loading dose of 0.5 mg/kg ketamine followed by a continuous infusion of 10.0 µg/kg/min led to a significant decrease in the MACBAR of sevoflurane in patients undergoing laparoscopic cholecystectomy.

Fentanyl inhibits acute myeloid leukemia differentiated cells and committed progenitors via opioid receptor-independent suppression of Ras and STAT5 pathways.

Fentanyl is a common sedative/analgesic used for intrathecal chemotherapy injection in children with acute leukemia. Given the contradictory findings that fentanyl has both inhibitory and stimulatory activities in cancer cells, we investigated the biological effects of fentanyl alone and its combination with standard of care in acute myeloid leukemia (AML) cells at all stages of development. We showed that fentanyl at clinically relevant concentration inhibited growth and colony formation of AML differentiated cells and committed progenitors without affecting their survival. Compared to AML cells without FLT3 mutation, cells harboring FLT3-ITD mutation are likely to be more sensitive to fentanyl. However, fentanyl did not affect the most primitive AML stem cells. Fentanyl significantly augmented the efficacy of cytarabine but not midostaurin in AML differentiated cells and committed progenitors. We further demonstrated that fentanyl inhibited AML cells via suppressing Ras/Raf/MEK/ERK and STAT5 pathway, and this was not dependent on opioid receptor system. Our findings demonstrate the anti-leukemia activity of fentanyl and synergistic effects between fentanyl and cytarabine in AML, via opioid receptor-independent suppression of Ras and STAT5 pathways. Our work is the first to suggest the beneficial effects of fentanyl in children with leukemia.

Near-infrared triggered on-demand local anesthesia using a jammed microgels system.

To conveniently modulate the degree of local analgesia in response to changes in patients' needs and level of activity, a NIR-activated drug delivery system based on jammed microgels was introduced in the present study to realize on-demand local anesthesia. Chemically cross-linked gelatin microgels (5-15 µm) containing N-isopropylacrylamide (NIPAM), methylallyl polyethylene glycol (APEG) and graphene oxide (GOs) were fabricated through emulsion. After the in situ free radical polymerization, the physical network was formed, producing microgels with double networks (DN microgels). The DN microgels exhibited thermosensitive properties. The copolymerization of APEG resulted in the increase of lower critical solution temperature (LCST) of microgels. The maximum volume shrinkage ratio of DN microgels (NIPAM40 + APEG60) increased with the increase of the content of physical cross-linking network. The DN microgels also exhibited NIR-responsive ability. Under the NIR irradiance of 272 mW/cm2, the temperature of DN microgels with 3 mg/mL GOs reached 40 °C within 60 s, resulting in the volume shrinkage of 14%. Ropivacaine release from DN microgels could be effectively triggered by NIR irradiation in vitro. After centrifugation, a jammed microgels system was produced where microgels packed densely, displaying shear-thinning behavior for achieving injection. The jammed DN microgels carrying ropivacaine were injected subcutaneously into rat footpad. NIR irradiation produced on-demand and repeated infiltration anesthesia in the rat footpad. The jammed DN microgels system thus was beneficial in the management of pain.

Shape memory materials promoting cell adhesion and tissue invasion towards the applications requiring minimally invasive implantation.

Minimally invasive implantation of porous implants with large volume for in vivo filling proposes high requirements for material preparation. Porous scaffolds based on shape memory polymer (SMP) possess great potential for being delivered as the compact form via minimally invasive surgery. Here, poly (ε-caprolactone)-dienes (PCL-dienes) and crylic acid (AA) were polymerized and cross-linked to fabricate SMP scaffolds, the porous structure of which was created through particle leaching method. Three scaffolds, PAA-PCL20, PAA-PCL50 and PAA-PCL80 were fabricated with different content of PCL-dienes, possessing similar pore size (350 µm) and porosity (85%). PAA-PCL50 scaffold had a Tm of 38 °C, exhibiting shape fixing ability at room temperature and shape recovery ability at body temperature. All scaffolds showed limited interaction with cells. The cell adhesion rate of PAA-PCL50 scaffold was 55%, the highest among the three scaffolds. To promote cellular adhesion, PAA-PCL50 scaffold was mineralized via in situ precipitation, exhibiting CaP particles on the inner surfaces. The mineralized scaffold still exhibited well-performed deformation and shape memory ability, with higher cell adhesion rate (86%) and proliferation rate. In vivo implantation result indicated that the mineralized PAA-PCL50 scaffold better supported tissue invasion, holding a great promise to improve neo-tissue formation.

Non-stimulation needle with external indwelling cannula for brachial plexus block and pain management in 62 patients undergoing upper-limb surgery.

OBJECTIVE: To investigate the feasibility of a non-stimulation needle with an external indwelling cannula for upper-limb surgery and acute postoperative pain management. METHODS: 62 patients undergoing either scheduled or emergency upper-limb surgery received brachial plexus block of modified interscalene or axillary brachial and then postoperative patient-controlled analgesia (PCA) with local analgesics using a specially designed non-stimulation needle with an external indwelling cannula. The outcome measurements included anesthetic effect, acute or chronic complications, postoperative analgesic effect and patient's satisfaction. RESULTS: The success rate of anesthesia was 96.8%. The single attempt placement with the external indwelling cannula was achieved in 85.2% of patients with axillary brachial plexus block and 78.8% with modified interscalene brachial plexus block. The incidence of severe intoxication was 3.7% with axillary brachial plexus block and 3.0% with modified interscalene brachial plexus block. No hematoma at the injection site, Horner's syndrome, hoarseness or dyspnea was observed. Postoperative analgesic effect was achieved in 100% and activities were slightly lowered in 91.7%. The incidence of nausea and vomit was 8.3%; patient's satisfaction was 9.1 on a 10-point scale system. Infection, nerve injury and respiratory depression were absent during the catheter indwelling. The indwelling time of external indwelling cannula was 30.5 h on average. There was no nerve injury related complication after withdrawing the external indwelling catheter. CONCLUSIONS: Brachial plexus block using a non-stimulation needle with an external indwelling cannula has favorable intra-operative anesthetic benefit and provides an excellent postoperative analgesic outcome. The low incidence of complications and favorable patient's satisfaction suggest that non-stimulation needle with an external indwelling cannula is a useful and safe anesthetic tool in brachial nerve block and acute postoperative pain management.

Propofol attenuates hepatic ischemia/reperfusion injury in an in vivo rabbit model.

BACKGROUND: Propofol has been demonstrated to improve hepatic perfusion in a rabbit model; however, the effects of propofol on hepatic ischemia/reperfusion injury are unknown. The aim of the present study was to determine whether propofol has a hepatoprotective effect using an in vivo ischemia/reperfusion model in rabbits. METHODS: A total of 48 rabbits were randomly assigned to two groups: a propofol group (0.6 mg · kg(-1) · min(-1)) or a control group (10% intralipid, 0.6 mg · kg(-1) · min(-1)). Each group was then further divided into three subgroups of 8 rabbits according to the duration (10, 30, and 60 min) of propofol infusion before an ischemic episode was induced by cross-clamping the left hepatic artery and hepatic portal vein. Hepatic ischemia was maintained for 30 min, and the rabbits were monitored for 60 min after reperfusion. Liver enzyme leakage and histopathologic examination were used to evaluate the extent of hepatic ischemia/reperfusion injury. RESULTS: The serum enzyme levels were the same in all groups before the ischemic episode. After the induction of ischemia/reperfusion, the liver enzymes were significantly increased in all rabbits compared with baseline values (P < 0.05). Propofol significantly decreased the leakage of liver enzymes and markedly reduced lesions in histologic examination of the liver compared with the control group (P < 0.05). However, no significant difference was found in serum enzyme levels among the three subgroups in the propofol group. CONCLUSIONS: Propofol reduced hepatic ischemia/reperfusion injury in an in vivo rabbit model; however, the duration of propofol infusion before the ischemic insult did not influence its hepatoprotective effects or the extent of hepatic injury.

Effect of propofol on hepatic blood flow and oxygen balance in rabbits.

PURPOSE: Propofol has been reported to alter hepatic blood flow and to increase hepatic oxygen consumption. This study was designed to determine the effect of propofol on hepatic blood flow and oxygenation in rabbits, in order to establish its net effect on hepatic oxygen balance. METHODS: Twenty, adult male, New Zealand white rabbits were randomly divided into two groups: Group P (propofol, 0.6 mg.kg(-1).min(-1)) or Group C (10% intralipid, 0.6 mg.kg(-1).min(-1)). An electromagnetic flowmeter was used to measure hepatic blood flow, and blood, from the carotid artery, the portal vein, and the hepatic vein, was used to determine hepatic oxygenation. After we obtained baseline values, we repeated measurements ten, 30, and 60 min after initiating the infusion. RESULTS: Intralipid did not affect systemic hemodynamics, hepatic blood flow, or oxygenation during the 60 min infusion; however, propofol caused a time-dependent decrease in mean arterial blood pressures and an increase in portal venous flow and total hepatic blood flow. In contrast, hepatic arterial blood flow remained unchanged during the propofol infusion. Hepatic oxygen delivery and consumption increased in a time-dependent manner to maximums of 25% and 21.4% (both, P < 0.05) above baseline, respectively. Hepatic venous oxygen saturation and extraction was unchanged throughout the study period. CONCLUSION: Propofol increases total hepatic blood flow, primarily by increasing hepatic portal venous flow. The increase in liver oxygen consumption was fully compensated by an increase in oxygen supply to the liver, resulting in a preserved, hepatic oxygen balance.