Urinary oxygen tension and its role in predicting acute kidney injury: A narrative review.

Acute kidney injury occurs frequently in the perioperative setting. The renal medulla often endures hypoxia or hypoperfusion and is susceptible to the imbalance between oxygen supply and demand due to the nature of renal blood flow distribution and metabolic rate in the kidney. The current available evidence demonstrated that the urine oxygen pressure is proportional to the variations of renal medullary tissue oxygen pressure. Thus, urine oxygenation can be a candidate for reflecting the change of oxygen in the renal medulla. In this review, we discuss the basic physiology of acute kidney injury, as well as techniques for monitoring urine oxygen tension, confounding factors affecting the reliable measurement of urine oxygen tension, and its clinical use, highlighting its potential role in early detection and prevention of acute kidney injury.

Cell membrane-based nanomaterials for theranostics of central nervous system diseases.

Central nervous system (CNS) diseases have been widely acknowledged as one of the major healthy concerns globally, which lead to serious impacts on human health. There will be about 135 million CNS diseases cases worldwide by mid-century, and CNS diseases will become the second leading cause of death after the cardiovascular disease by 2040. Most CNS diseases lack of effective diagnostic and therapeutic strategies with one of the reasons that the biological barrier extremely hampers the delivery of theranostic agents. In recent years, nanotechnology-based drug delivery is a quite promising way for CNS diseases due to excellent properties. Among them, cell membrane-based nanomaterials with natural bio-surface, high biocompatibility and biosafety, are of great significance in both the diagnosis and treatment of different CNS diseases. In this review, the state of art of the fabrication of cell membranes-based nanomaterials is introduced. The characteristics of different CNS diseases, and the application of cell membranes-based nanomaterials in the theranostics are summarized. In addition, the future prospects and limitations of cell membrane nanotechnology are anticipated. Through summarizing the state of art of the fabrication, giving examples of CNS diseases, and highlighting the applications in theranostics, the current review provides designing methods and ideas for subsequent cell membrane nanomaterials.

Effects of different depth of anesthesia on perioperative inflammatory reaction and hospital outcomes in elderly patients undergoing laparoscopic radical gastrectomy.

BACKGROUND: To investigate the effect of different depth of anesthesia on inflammatory factors and hospital outcomes in elderly patients undergoing laparoscopic radical gastrectomy for gastric cancer, in order to select an appropriate depth of anesthesia to improve the prognosis of patients undergoing surgery and improve the quality of life of patients. METHODS: A total of 80 elderly patients aged 65 and above who underwent laparoscopic radical gastrectomy in our hospital were by convenience sampling and randomly divided into two groups : 55 groups ( group H ) and 45 groups ( group L ), 40 cases in each group. The depth of anesthesia was maintained using a closed-loop target-controlled infusion system: the EEG bispectral index was set to 55 in the H group and 45 in the L group. Venous blood samples were collected 2 h (T2), 24 h (T3) and 72 h (T4) after the start of surgery. The intraoperative dosage of propofol and remifentanil, operation duration, postoperative PACU stay time, intraoperative consciousness occurrence, postoperative hospital stay and postoperative pulmonary inflammatory events were recorded. RESULTS: The patient characteristic of the two groups had no statistical difference and were comparable (P > 0.05). The intraoperative dosage of propofol in group H was lower than that in group L (P < 0.05). Compared with the L group, the plasma IL-6 and IL-10 concentrations in the H group were significantly increased at T2 (P < 0.05), and the plasma IL-10 concentration was significantly increased at T4 (P < 0.05). The plasma concentrations of IL-6 and IL-10 were higher in both groups at T2, T3 and T4 than at T1, while at T4, the concentration of TNF-α in group H was higher than at T1 (P < 0.05). CONCLUSION: When the BIS value of the depth of anesthesia is 45, the perioperative release of inflammatory factors in elderly patients with laparoscopic radical gastrectomy for gastric cancer is less than BIS 55, and does not affect the prognosis.

Provisional Decision-Making for Perioperative Blood Pressure Management: A Narrative Review.

Blood pressure (BP) is a basic determinant for organ blood flow supply. Insufficient blood supply will cause tissue hypoxia, provoke cellular oxidative stress, and to some extent lead to organ injury. Perioperative BP is labile and dynamic, and intraoperative hypotension is common. It is unclear whether there is a causal relationship between intraoperative hypotension and organ injury. However, hypotension surely compromises perfusion and causes harm to some extent. Because the harm threshold remains unknown, various guidelines for intraoperative BP management have been proposed. With the pending definitions from robust randomized trials, it is reasonable to consider observational analyses suggesting that mean arterial pressures below 65 mmHg sustained for more than 15 minutes are associated with myocardial and renal injury. Advances in machine learning and artificial intelligence may facilitate the management of hemodynamics globally, including fluid administration, rather than BP alone. The previous mounting studies concentrated on associations between BP targets and adverse complications, whereas few studies were concerned about how to treat and multiple factors for decision-making. Hence, in this narrative review, we discussed the way of BP measurement and current knowledge about baseline BP extracting for surgical patients, highlighted the decision-making process for BP management with a view to providing pragmatic guidance for BP treatment in the clinical settings, and evaluated the merits of an automated blood control system in predicting hypotension.

The Effect of Oxycodone on Post-operative Pain and Inflammatory Cytokine Release in Elderly Patients Undergoing Laparoscopic Gastrectomy.

Background: To evaluate the effect of oxycodone on post-operative pain and inflammation in elderly patients undergoing laparoscopic gastrectomy. Methods: Sixty patients who were of both sexes, American Society of Anesthesiologists Physical Status (ASA-PS) Class I or II, over 65 years of age and undergoing an elective laparoscopic radical gastrectomy were randomly divided into two groups: an oxycodone group (Group O) including 20 males and 10 females and a sufentanil group (Group S) including 21 males and 9 females. The post-operative analgesia regimen was as follows: 40 mg of parecoxib sodium and 0.1 mg/kg of oxycodone was intravenously injected into Group O before the abdomen closure, while 40 mg of parecoxib sodium and 0.1 µg/kg of sufentanil was injected intravenously into Group S. Both groups were infiltrated with 20 ml of 1% ropivacaine at the end of the operation. The level of serum IL-6 and IL-10 were assayed immediately at the following timepoints: at the conclusion of surgery (T1), 1 h (T2), 6 h (T3), and 24 h (T4) after the completion of the surgery. The numerical rating scale (NRS), the Ramsay sedation score, analgesic-related adverse events, post-operative pulmonary inflammation events and the post-operative stay were recorded. Results: Compared with Group S, the serum IL-6 concentrations of Group O decreased at T3 and T4, while the serum IL-10 concentrations increased (P < 0.05). In Group O, the serum IL-6 concentrations at T3 and T4 were lower than those at T1 (P < 0.05). The incidence of post-operative nausea and vomiting (PONV) and pulmonary inflammation in Group O was lower than that in Group S (P < 0.05). At each time point, the NRS of visceral pain in Group O was lower than that in Group S. At 6 and 24 h after extubation, the NRS of incision pain in Group O was lower than that in Group S (P < 0.05). Conclusion: Oxycodone can regulate the level of inflammatory cytokines and reduce post-operative inflammatory response.

Effect of Intravenous Oxycodone in Combination With Different Doses of Dexmedetomdine on Sleep Quality and Visceral Pain in Patients After Abdominal Surgery: A Randomized Study.

OBJECTIVE: Oxycodone or dexmedetomidine (DEX) alone are widely used in clinical practice. The aim of this study was to observe the effect of 2 oxycodone and DEX combinations on postoperative sleep quality. METHODS: This was a prospective and randomized clinical study. A total of 99 patients underwent laparoscopic-assisted operations on stomach and intestines with general anesthesia were enrolled and randomly divided into 3 groups according to postoperative analgesic protocol (n=33 each). The analgesic protocols were as follows after the surgery. In group C, 0.6 mg/kg oxycodone alone was diluted to 100 mL in 0.9% saline. In group D1 or D2, 0.6 mg/kg oxycodone combined with 2.4 µg/kg or 4.8 µg/kg DEX was diluted to 100 mL in 0.9% saline, respectively. The intravenous patient-controlled analgesia device was set up to deliver a continuous infusion of 3 mL/h and a bolus of 1 mL, with a 12-minute lockout interval. The primary outcome was the percentage of stage 2 nonrapid eye movement (stage N2) sleep. Polysomnography was performed the night before operation (PSG-night0), the first (PSG-night1) and second (PSG-night2) nights after surgery. RESULTS: A total of 97 patients were included in the final analysis. Compared with group C, N2 sleep were higher in groups D1 and D2 on PSG-night1 (54±9% and 53±10%, respectively) and PSG-night2 (55±7% and 56±8%, respectively) (P<0.001 for all comparisons). No differences were observed regarding N1 and N2 sleep between groups D1 and D2 on PSG-night1 and PSG-night2 (P>0.05). Group C had higher percentage of N1 sleep on PSG-night1 (37±5%) and PSG-night2 (33±3%) when compared with groups D1 and D2 (P<0.001 for the comparisons). Groups D1 and D2 required lower rates of rescue analgesia (5% and 4.7%, respectively; P=0.012) and effective pressing times (10.7±4.8 times and 9.9±2.6 times, respectively; P<0.05) when compared with group C, whereas no statistical significance was found between groups D1 and D2. Furthermore, there were no significant difference about resting visual analogue scales at 4, 6, and 12 hours postoperatively between groups D1 and D2. In comparison with the other 2 groups, group D2 had a higher occurrence of postoperative hypotension (24.2%) (P<0.05), though without significant sinus bradycardia. DISCUSSION: DEX combined with oxycodone can improve sleep quality and provide good visceral analgesia. However, larger doses of DEX does not further improve sleep but increases the risk of hypotension.

Thermo-induced formation of unimolecular and multimolecular micelles from novel double hydrophilic multiblock copolymers of N,N-dimethylacrylamide and N-isopropylacrylamide.

Two novel double hydrophilic multiblock copolymers of N,N-dimethylacrylamide and N-isopropylacrylamide, m-PDMAp-PNIPAMq, with varying degrees of polymerization (DPs) for PDMA and PNIPAM sequences (p and q) were synthesized via consecutive reversible addition-fragmentation chain transfer (RAFT) polymerizations using polytrithiocarbonate (1) as the chain transfer agent (Scheme 1), where PDMA is poly(N,N-dimethylacrylamide) and PNIPAM is poly(N-isopropylacrylamide). The DPs of PDMA and PNIPAM sequences were determined by 1H NMR, and the block numbers, i.e., number of PDMAp-PNIPAMq sequences (n), were obtained by comparing the molecular weights of multiblock copolymers to that of cleaved products as determined by gel permeation chromatography (GPC). m-PDMA42-PNIPAM37 and m-PDMA105-PNIPAM106 multiblock copolymers possess number-average molecular weights (Mn) of 4.62x10(4) and 9.53x10(4), respectively, and the polydispersities (Mw/Mn) are typically around 1.5. Block numbers of the obtained multiblock copolymers are ca. 4, which are considerably lower than the numbers of trithiocarbonate moieties per chain of 1 (approximately 20) and m-PDMAp precursors (approximately 6-7). PDMA homopolymer is water soluble to 100 degrees C, while PNIPAM has been well known to exhibit a lower critical solution temperature (LCST) at ca. 32 degrees C. In aqueous solution, m-PDMA42-PNIPAM37 and m-PDMA105-PNIPAM106 multiblock copolymers molecularly dissolve at room temperature, and their thermo-induced collapse and aggregation properties were characterized in detail by a combination of optical transmittance, fluorescence probe measurements, laser light scattering (LLS), and micro-differential scanning calorimetry (micro-DSC). It was found that chain lengths of PDMA and PNIPAM sequences exert dramatic effects on their aggregation behavior. m-PDMA105-PNIPAM106 multiblock copolymer behaves as protein-like polymers and exhibits intramolecular collapse upon heating, forming unimolecular flower-like micelles above the thermal phase transition temperature. On the other hand, m-PDMA42-PNIPAM37 multiblock copolymer exhibits collapse and intermolecular aggregation, forming associated multimolecular micelles at elevated temperatures. The intriguing aggregation behavior of this novel type of double hydrophilic multiblock copolymers argues well for their potential applications in many fields such as biomaterials and biomedicines.