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Li-Juan Hu,1 Zhong Mei,1,2 Yan-Ping Shen,1 Hao-Tian Sun,1 Zhi-Min Sheng,1 Xin-Zhong Chen,1 Xiao-Wei Qian1 1Department of Anesthesiology, Women’s Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2Department of Anesthesiology, Affiliated Xiaoshan Hospital, Hangzhou Normal University, Hangzhou, People’s Republic of ChinaCorrespondence: Xiao-Wei Qian, Department of Anesthesiology, Women’s Hospital, Zhejiang University School of Medicine, Xueshi Road 1, Hangzhou, 310006, People’s Republic of China, Tel +86-571-87061501, Fax +86 571 87061878, Email qianxw@zju.edu.cnBackground: It is well-known that severe preeclamptic parturients have less vasopressor requirements than normotensive parturients; however, the exact dose difference is poorly documented. This study aimed to determine and compare the ED50 and ED90 of a single bolus phenylephrine for the treatment of spinal anesthesia-induced hypotension in parturients with severe preeclampsia and parturients with normotension.Methods: Seventy-five parturients with severe preeclampsia scheduled for cesarean delivery under combined spinal-epidural anesthesia were enrolled and randomly allocated to receive a single bolus of phenylephrine at five different doses (40, 50, 60, 70, and 80 μg), whereas 75 parturients with normotension were randomized to receive a single bolus of phenylephrine at five different doses (70, 80, 90, 100, and 110 μg) for the treatment of the first episode of hypotension. Phenylephrine dose values were log-transformed, the proportions of the successful interventions at each dose were converted to probits, and regression analysis was performed.Results: The ED50 and ED90 (95% CI) of bolus phenylephrine were 72.1 (61.7 to 79.9) μg and 107 (95.9– 128.6) μg in parturients with normotension. The ED50 and ED90 values in parturients with severe preeclampsia were 47.6 (41.3– 52.7) μg and 70.7 (62.9– 86.7) μg. The relative median potency was 1.51 (1.16– 2.61).Conclusion: Under this study conditions, severe preeclamptic parturients required a 34% reduction of ED50 of phenylephrine dose compared with normotensive parturients.Keywords: cesarean delivery, spinal anesthesia, hypotension, phenylephrine, preeclampsia

Jin-Ping Liu,1 Zheng-Bin Pan,1 Miao Zhu,1 Guo-Wei Zhu,2 Da-Bing Song,2 Xin-Zhong Chen,1 Xiao-Wei Qian1 1Department of Anesthesiology, Women’s Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2Department of Anesthesiology, Haining Maternal and Child Health Hospital, Jiaxing, People’s Republic of ChinaCorrespondence: Xiao-Wei Qian; Xin-Zhong ChenDepartment of Anesthesiology, Women’s Hospital, Zhejiang University School of Medicine, Xueshi Road 1, Hangzhou, 310006, People’s Republic of ChinaTel +86-571-87061501Fax +86 571 87061878Email qianxw@zju.edu.cn; chenxinz@zju.edu.cnPurpose: Treatment of spinal anesthesia-induced hypotension in patients with severe preeclampsia assumes special concern as hypotension may further reduce placental perfusion. Phenylephrine is still the first-line vasopressor for treating spinal anesthesia-induced hypotension. However, the optimal dose of phenylephrine used as intravenous (IV) boluses in patients with severe preeclampsia has not been clearly determined. We aim to calculate the 90% effective dose (ED90) of phenylephrine as IV boluses for treating spinal anesthesia-induced hypotension in patients with severe preeclampsia undergoing cesarean delivery.Patients and Methods: Forty patients with severe preeclampsia were enrolled in this prospective sequential allocation dose-finding trial. Using the biased coin up-and-down (BCUD) method, all patients in our study received an IV bolus phenylephrine of either 40, 50, 60, 70, or 80 μg when the mean arterial pressure (MAP) decreased to less than 80% of the baseline level and the ED90 was determined. The primary outcome was the success of the assigned phenylephrine bolus to maintain the MAP at or above 80% of baseline value between the induction of spinal anesthesia and delivery of the fetus. Secondary outcomes included hypertension, nausea, vomiting, bradycardia, upper sensory level of anesthesia, umbilical blood gases, and Apgar score. Estimating of the ED90 with 95% confidence interval (CI) was achieved by isotonic regression method.Results: The ED90 of phenylephrine was estimated as 62.00 μg (95% CI=50.00– 67.40 μg) using the isotonic regression method. No patients enrolled in our study experienced bradycardia and those patients who developed hypertension were all observed at the dose level 70 μg.Conclusion: For clinical practice, we recommend that phenylephrine 60 μg may be both effective and safe for treatment of spinal anesthesia-induced hypotension in severe preeclampsia during cesarean delivery.Keywords: phenylephrine, hypotension, preeclampsia, biased coin up-and-down method, ED90

Oxycodone hydrochloride injection could be safely and effectively applied to negative pressure aspiration, and a 0.08 mg/kg dose could significantly reduce postoperative uterine contraction pain of patients with dysmenorrhea.

Background: Patients at high risk of obstructive sleep apnea (OSA) are prone to hypoxemia during sedated bronchoscopy. The present study aimed to investigate whether high-flow nasal oxygenation (HFNO) reduces the incidence of hypoxemia in patients at high risk of OSA undergoing bronchoscopy under deep sedation.Methods: A total of 176 patients at high risk of OSA who underwent bronchoscopy under deep sedation were randomly assigned into two groups: the HFNO group (humidified oxygen was supplied via a high-flow nasal cannula at a rate of 60 L/min and a concentration of 100%, n = 87) and the Facemask group (oxygen was supplied via tight-fitting facemask at a rate of 6 L/min and a concentration of 100%, n = 89).Results: Hypoxemia occurred in 4 (4.6%) patients in the HFNO group and 26 (29.2%) patients in the Facemask group (P < 0.001). The Facemask group required more jaw thrust maneuvers than the HFNO group (48.3% vs 5.7%, P < 0.001). A total of 9.0% of the patients in the Facemask group and no one in the HFNO group required bag-mask ventilation (P = 0.012).Conclusions: HFNO can reduce the incidence of hypoxemia and the requirement of airway intervention in patients at high risk of OSA during bronchoscopy under deep sedation.Trial registration: www.chiCTR.org.cn Identifier: ChiCTR2100044105. Registered 11/03/2021.

Purpose Oxytocin is the first-line agent to prevent and treat uterine atony during cesarean delivery (CD). We compared the effective dose in 50% of the parturients (ED50) of a prophylactic oxytocin bolus during CD in young (

ImportanceEpidural anesthesia is a primary choice for cesarean delivery, but supplemental analgesics are often required to relieve pain during uterine traction.ObjectiveTo investigate the sedative and analgesic effects of intravenous esketamine administered before childbirth via cesarean delivery with the patient under epidural anesthesia.Design, Setting, and ParticipantsThis multicenter, double-blind randomized clinical trial assessed 903 women 18 years or older who had full-term single pregnancy and were scheduled for elective cesarean delivery with epidural anesthesia in 5 medical centers in China from September 18, 2021, to September 20, 2022.InterventionPatients were randomized to receive intravenous injection of 0.25 mg/kg of esketamine or placebo before incision.Main Outcomes and MeasuresThe coprimary outcomes included scores on the numeric rating scale of pain (an 11-point scale, with 0 indicating no pain and 10 indicating the worst pain; a difference of ≥1.65 points was clinically meaningful) and Ramsay Sedation Scale (a 6-point scale, with 1 indicating restlessness and 6 indicating deep sleep without response; a difference of ≥2 points was clinically meaningful) immediately after fetal delivery. Secondary outcomes included neonatal Apgar score assessed at 1 and 5 minutes after birth.ResultsA total of 600 women (mean [SD] age, 30.7 [4.3] years) were enrolled and randomized; all were included in the intention-to-treat analysis. Immediately after fetal delivery, the score on the numeric rating scale of pain was lower with esketamine (median [IQR], 0 [0-1]) than with placebo (median [IQR], 0 [0-2]; median difference, 0; 95% CI, 0-0; P = .001), but the difference was not clinically important. The Ramsay Sedation Scale scores were higher (sedation deeper) with esketamine (median [IQR], 4 [3-4]) than with placebo (median [IQR], 2 [2-2]; median difference, 2; 95% CI, 2-2; P P = .98) and at 5 minutes (median difference, 0; 95% CI, 0-0; P = .27). Transient neurologic or mental symptoms were more common in patients given esketamine (97.7% [293 of 300]) than in those given placebo (4.7% [14 of 300]; P Conclusions and RelevanceFor women undergoing cesarean delivery under epidural anesthesia, a subanesthetic dose of esketamine administered before incision produced transient analgesia and sedation but did not induce significant neonatal depression. Mental symptoms and nystagmus were common but transient. Indications and the optimal dose of esketamine in this patient population need further clarification, but study should be limited to those who require supplemental analgesia.Trial RegistrationClinicalTrials.gov Identifier: NCT04548973

Background The 90% effective dose (ED90) of oxytocin infusion has been previously estimated to be 16.2 IU h− 1. However, bolus administration of oxytocin prior to the infusion may decrease the infusion dose required. The aim of this study was to estimate the ED95 for oxytocin infusion after a bolus at elective caesarean delivery (CD) in nonlaboring parturients. Methods We performed a randomized, triple blinded study in 150 healthy termparturients scheduled for elective CD under epidural anaesthesia. After delivery of the infant and i.v. administration of 1 IU oxytocin as a bolus, Participants were randomized to receive oxytocin infusion at a rate of 0, 1, 2, 3, 5, or 8 IU h− 1, to be given for a total of 1 h. Uterine tone assessed by the blinded obstetrician as either adequate or inadequate. Secondary outcomes included estimated blood loss (EBL), requirement for supplemental uterotonic agents, and development of side effects. Results The 95% effective dose (ED95) of oxytocin infusion was estimated to be 7.72 IU h− 1 (95% confidence interval 5.80–12.67 IU h− 1). With increasing oxytocin infusion rate, the proportion of parturients who needed rescue oxytocin bolus or secondary uterotonic agents decreased. No significant among-group differences in the EBL and oxytocin-related side effects were observed. Conclusions In parturients who receive a 1 IU bolus of oxytocin during elective cesarean delivery, an infusion rate of oxytocin at 7.72 IU h− 1 will produce adequate uterine tone in 95% of parturients. These results suggest that the total dose of oxytocin administered in the postpartum period can be decreased when administered as an infusion after oxytocin bolus.

Purpose: Prophylactic infusion of a vasopressor is preferred as a rational choice in clinical practice in Cesarean delivery. Metaraminol is one of most common vasopressors used in obstetric clinical practice. However, the dose-response of metaraminol has not been fully determined and the optimal infusion dose is unknown. Therefore, this study aimed to determine the median effective dose (ED50) and 90% effective dose (ED90) of weight-based fixed-rate metaraminol infusions for preventing spinal-anesthesia-induced hypotension in patients having combined spinal-epidural anesthesia for elective Caesarean delivery.Methods: One hundred and seventeen patients with singleton pregnancies were enrolled and randomly allocated into one of five groups in this study. Patients received prophylactic metaraminol infusion at a fixed rate of 0, 0.25, 1.0, 1.75 or 2.5 μg/kg/min in each group immediately after induction with intrathecal 10 mg of hyperbaric bupivacaine mixed with 5 μg of sufentanil. An effective prophylactic dose was defined as no occurrence of hypotension during the period of spinal introduction and neonatal delivery. Values for ED50 and ED90 of prophylactic infusion of metaraminol were calculated using probit regression. Characteristics of spinal anesthesia and side effects were recorded.Results: The ED50 and ED90 values of weight-based fixed rate of metaraminol infusion were 0.64 (95% CI, 0.04–1.00) μg/kg/min and 2.00 (95% CI, 1.58–2.95) μg/kg/min respectively. The incidence of hypotension decreased with an increased infusion rate of metaraminol in the five groups (test for trend, p < 0.001). The incidence of hypotension was similar between group 0 and 0.25, but significant higher than other groups; the incidence of hypotension was also similar between group 1.0 and 1.75, but higher than group 2.5. The incidence of reactive hypertension was significantly higher in group 2.5 compared to the other groups. Physician interventions were more frequent in group 0, 0.25 and 2.5 than in group 1.0 and 1.75 (adjusted p < 0.001). No difference was found in neonatal outcomes, including Apgar score and pH value of the umbilical artery.Conclusion: In summary, we have compared four different prophylactic weight-based infusion doses of metaraminol for preventing post-spinal hypotension in Cesarean delivery. The ED50 and ED90 values of metaraminol infusion for preventing spinal anesthesia-induced hypotension were 0.64 μg/kg/min and 2.00 μg/kg/min, respectively. This finding may be helpful for guiding clinical practice and further research.

The photoplethysmogram (PPG) of a pulse wave, similar in appearance to the arterial blood pressure (ABP) waveform, contains rich information about the cardiovascular system. The decay time constant RC, equal to the product of peripheral resistance R and total arterial compliance C, is a meaningful cardiovascular model parameter in vascular assessment. Using or ameliorating the existing ABP methods does not achieve a satisfactory estimation of RC from the PPG volume pulse (VRC). Thus, a novel non-iterative shape method (NSM) of evaluating VRC is introduced in this paper. The mathematic expression between a novel, readily available morphological parameter called the area difference ratio (ADR) and VRC was established. As it was difficult to calculate VRC from the complicated expression analytically, we recommend estimating it using a piecewise linear interpolation criterion. Also, since the effect of the PPG magnitude is eliminated in the calculation of ADR, precaliberation or normalization is dispensable in the NSM. Results of human experiments indicated that the NSM was computationally efficient, and the simulation experiments confirmed that the NSM was theoretically available for ABP.

To investigation the effect of ropivacaine on the contraction of the isolated human umbilical artery and the mechanisms involved.Endothelium-denuded human umbilical artery rings obtained from healthy full-term parturients were prepared. Using isometric force transducers and a fluorometer, the effect of ropivacaine in cumulative concentration on the contraction response induced by KCl in the presence or absence of verapamil, or verapamil plus ruthenium red or verapamil plus heparin was observed. Furthermore, the effect of ropivacaine on the contraction response of the artery rings incubated in different concentrations of extracellular Ca(2+) was also observed.Ropivacaine induced a dose-dependent biphasic contractile response of human umbilical artery rings: increasing at concentrations of 1.0 x 10(-5) to 1.0 x 10(-4) mol/L and decreasing from 3.0 x 10(-4) to 3.0 x 10(-3) mol/L, which was inhibited by verapamil, or verapamil plus ruthenium red, or verapamil plus heparin. No difference was found between pre-treatment of verapamil, verapamil plus ruthenium red and verapamil plus heparin. Ropivacaine induced no contractile response in Ca(2+)-free solution and a extracellular Ca(2+) dose-dependent increasing contractile response (1.0 x 10(-4) to 3.0 x 10(-2) mol/L).Ropivacaine induced a dose-dependent biphasic contractile response of human umbilical artery rings. The increase in intracellular Ca(2+) concentrations by the extracellular Ca(2+) influx, not by the release from the sarcoplasmic reticulum, is involved in ropivacaine-induced vasoconstriction of human umbilical artery smooth muscle.

New target controlled infusion (TCI) for propofol using a hybrid physiologically based pharmacokinetic (PBPK) model was proposed in this paper. The hybrid model was composed of a three-compartment mamillary systemic model and a two-compartment brain model. A closed-loop control algorithm with brain concentration as the control variable was used to calculate the infusion. Finally, the dose regimen was applied in clinical practice and the recorded auditory evoked potentials showed good depth of anaesthesia. The TCI was feasible and had potential applications.

People who travel to a place may not know well about the information of the sites. Fortunately, people may have a personal device such as a mobile phone which has a digital camera and broadband wireless accesses, and the device can serve as a convenient equipment to access the information of geographic locations when people visit the place. This paper presents a system, called the GLOBE (GLobe On moBilE), consisting of a mobile, a client and a server. The GLOBE mobile is a mobile phone equipped with GPS, height, direction, angle sensors which are used to estimate the three-dimensional (3D) geographic location on the earth of the objects in the photo. The GLOBE client and server can manage these photos with 3D location information, annotate the objects on the photo, associate the information and travel notes with the photos, and share their photos with people on the Internet. Therefore, people just use the GLOBE mobile to take a picture on the object that they feel interested during a trip, and can immediately obtain the information of the object by searching on the GLOBE server. The proposed system helps people to learn information behind sites and objects they visited, and helps users to manage and share the information during atrip.

To explore the relation between human heat shock protein 70 (HSP70) and Toll-like receptor-4 (TLR4) in human monocytes.Periphery blood mononuclear cells were isolated from the samples of healthy blood donors' whole blood and monocytes were prepared and cultured. HSP70 of the final concentrations of 2.5 microg/ml, 5.0 microg/ml, 7.5 microg/ml, and 10 microg/ml respectively was added; 6 hours later the concentration of TNF-alpha in the supernatant was detected. Another monocytes were cultured and HSP70 of the final concentration of 5.0 microg/ml was added and the concentrations of NF-kappaB were detected 0, 30, 60, and 120 minutes later respectively. TLR4 blocker of the final concentrations of 5 microg/ml, 20 microg/ml, and 30 microg/ml respectively was added into another culture for 30 minutes and 5.0 microg/ml HSP70 was added, then immunochemistry was used to detect the concentration of NF-kappaB 120 minutes after ELISA was used to detect the concentration of and TNF-alpha 8 hours later. In order to examine the influence of HSP70 on the TLR4 in the cytomembrane of monocytes, HSP70 of the final concentration of 5.0 microg/ml was added into the culture of monocytes for 0, 30, 60, and 120 minutes respectively then flow cytometry was used to detect the mean fluorescence intensity (MFI) of TLR4.HSP70 stimulation increased the TNF-a concentration in the supernatant dose-dependently. The percentages of NF-kappaB positive monocytes were 38 +/- 6, 67 +/- 12, and 54 +/- 12 30 min, 60 min, 120 min after HSP70 stimulation, all significantly higher than that at the beginning of experiment (17 +/- 6, P0.05, P0.01, and P0.01). The percentages of NF-kappaB positive monocytes were 39% +/- 4%, 32% +/- 6%, and 28% +/- 6% 120 minutes after anti-TLR4 mAb stimulation, all significantly lower than that of the control group (67% +/- 12%, all P0.05). TLR4 blocker of different concentrations significantly inhibited the TNF-alpha secretion by the monocytes (all P0.05). The MFI of TLR4 in the cytomembrane of monocyte was significantly down-regulated 60 minutes, especially 120 minutes, after the HSP70 stimulation in comparison with that before the stimulation (P0.05 and P0.01).TLR4 appears to be involved in HSP70-mediated activation of innate immunity.

In terms of the characteristic of anesthetic operation, this paper propose new Physiologically Based Pharmacokinetics / Pharmacodynamics (PBPK/PD) model that focus on the important role of Autonomic Nervous System (ANS) more. Automatic nervous system that is divided into the sympathetic nervous system and the parasympathetic nervous system, at the same time, is the important target of drug effect in anesthesia. Consequently, Not only does the action levels of Automatic Nervous System indicator the Anesthesia State, but feed back altering the physiological state parameters of pharmacokinetics, which being one crucial reason of time-variant and nonlinear drug effect. However, the recent PBPK modeling and simulation strategy only estimate specific absorption, distribution, metabolism and excretion (ADME) parameters but consider no modulation result of Automatic Nervous System any longer. So far, in order to avoid over-interpreted data from mathematical models and to take more consideration of clinical significance, the PBPK/PD model with Automatic Nervous System presented is helpful to make clearer relationship between PK and PD, that between sophisticated of model and real physiological phenomenon in Anesthesia than before.

In this paper we introduce the information mining technology, in which the main research contents are structured data and complex structured data mining. Taking information mining as a core concept, this paper combines the seven-bases (model base, integrated knowledge base, database, method base, text base, web log base and multimedia base) with the double-networks (Internet and intranet), and puts forward a new intelligent decision support system based on the information mining (IDSSIM). IDSSIM can improve the IDSS's ability of mining and processing semi-structured and unstructured data, in order that the decision support system adapts to the multiplicity and dynamicity of the present information source and provides more abundant decision support information.

Currently, the World-Wide Web has developed to a distributed information space with nearly 100 million workstations and several billion pages, which causes problems for people trying to find required information amongst the huge amount of information available. The search engine is a very important tool for people to obtain information on the Internet, but low-precision and low-recall exist widely in current search engines. With the rapid development of the Internet, effective and accurate intelligent search engines based on Web mining technology have become important. This paper introduces the theory and correlative conception of the search engine and then the definition, classification and the application of Web mining are described. Finally, important applications of Web mining technology in intelligent search engines are discussed in detail.

The effect of transcutaneous electrical acupoint stimulation (TEAS) on enflurane anesthesia and hemodynamic changes during craniotomy was studied. Eighty neurosurgical patients were randomly divided into two groups. Anesthesia was induced with fentanyl, droperidol, thiopental, and suxamethonium by intubation. In group A, anesthesia was maintained with enflurane (n=40), and in group B was supplemented by TEAS with Han's acupoint nerve stimulator (HANS) to Hegu, Yuyao, and Fengchi points on the operated side (n=40). The results showed that the ratio between expired concentration and minimum alveolar concentration of enflurane during operation in group B was 37.8%–47% lower than that in group A, and that the hemodynamics were more stable during operation. The results also demonstrated that the patients in Group B recovered faster after operation. It was concluded that TEAS with HANS significantly potentiated the anesthetic effect of enflurane.