Hemodynamic monitoring and management of patients undergoing high-risk surgery:a survey among Chinese anesthesiologists

Hemodynamic monitoring and optimization improve postoperative outcome during high-risk surgery.However,hemodynamic management practices among Chinese anesthesiologists are largely unknown.This study sought to evaluate the current intraoperative hemodynamic management practices for high-risk surgery patients in China.From September 2010 to November 2011,we surveyed anesthesiologists working in the operating rooms of 265 hospitals representing 28 Chinese provinces.All questionnaires were distributed to department chairs of anesthesiology or practicing anesthesiologists.Once completed,the 29-item questionnaires were collected and analyzed.Two hundred and 10 questionnaires from 265 hospitals in China were collected.We found that 91.4%of anesthesiologists monitored invasive arterial pressure,82.9%monitored central venous pressure(CVP),13.3%monitored cardiac output(CO),10.5%monitored mixed venous saturation,and less than 2%monitored pulse pressure variation(PPV) or systolic pressure variation(SPV) during high-risk surgery.The majority(88%) of anesthesiologists relied on clinical experience as an indicator for volume expansion and more than 80%relied on blood pressure,CVP and urine output.Anesthesiologists in China do not own enough attention on hemodynamic parameters such as PPV,SPV and CO during fluid management in high-risk surgical patients.The lack of CO monitoring may be attributed largely to the limited access to technologies,the cost of the devices and the lack of education on how to use them.There is a need for improving access to these technologies as well as an opportunity to create guidelines and education for hemodynamic optimization in China.

Early and marked up-regulation of TNF-α in acute respiratory distress syndrome after cardiopulmonary bypass

Despite the technique of cardiopulmonary bypass(CPB)improved the development of modern cardiac surgery,many factors during CPB have been reported to induce acute respiratory distress syndrome(ARDS).The present study was to investigate which pro-inflammatory factors involved in the early phase of ARDS.Ten patients underwent valve replacement surgery with or without ARDS were enrolled for analysis of pulmonary function and inflammatory factors release including white blood cell(WBC),neutrophils,CD11b,CD18,interleukin(IL)-8 and tumor necrosis factor-α(TNF-α).The results demonstrated that the ratio of arterial oxygen tension/fraction of inspire oxygen(PaO_(2)/FiO_(2))was greatly reduced in ARDS patients,but only the release of TNF-α was significantly increased,which was reversely correlated to the values of PaO_(2)/FiO_(2).Also,the count of neutrophils adhesive to pulmonary endothelial cells was significantly increased in ARDS patients.Therefore,we concluded that TNF-α was quickly up-regulated and involved in the pathogenesis of CPB-induced ARDS via guiding primed neutrophils to pulmonary interstitium.

EMLA■ Cream coated on endotracheal tube with or without epidural lidocaine reduces isoflurane requirement during general anesthesia

This study was designed to evaluate the effect of tracheal topical anesthesia using EMLA■Cream(EC)coated on the endotracheal tube(ETT)with or without epidural anesthesia(EA)on isoflurane requirement during general anesthesia(GA)and investigate whether EC coated on the ETT with EA was associated with the additive effect compared with the effect when each anesthetic was administered independently.The prospective randomized,double-blinded,and controlled study included 60 ASA Ⅰ-Ⅱ patients scheduled for upper abdominal surgery requiring GA.Patients were randomly assigned to one of the following groups:group 1 received GA,group 2 received EC+GA,group 3 received GA+EA,and group 4 received EC+GA+EA.Isoflurane was administered at the required concentrations to maintain the mean arterial pressure at a level not exceeding 20% of preoperative values.The percentage mean expired concentration(%MEC)was used in calculating the isoflurane requirement.Emergence agitation,postoperative sore throat,and hoarseness were recorded.Groups 2,3,and 4 exhibited a significant reduction on isoflurane requirement compared with group 1(P<0.05).The isoflurane requirement evaluated by%MEC decreased by 12%,38%,and 50% in groups 2,3,and 4,respectively.The incidence of emergence agitation was significantly lower in groups 2 and 4 than those in groups 1 and 3(P<0.05).Tracheal topical anesthesia using EC coated on ETT with or without EA reduced the isoflurane requirement during GA,indicating that EC combined with EA exhibited an additive effect on the requirement of general anesthetic.

Estimation of the minimum effective dose of tramadol for postoperative analgesia in infants using the continual reassessment method

Tramadol is a potent analgesic.However,the analgesia efficacy of tramadol,particularly its minimum effective dose(MED),is not clear.The aim of this study is to find MED of tramadol for postoperative analgesia in infants.The continual reassessment method(CRM)was performed to find MED.Infants undergoing surgeries were included in the 3 phases of this series.In each phase,24 participants were allocated a different tramadol dose.Pain intensity was measured by face,legs,activity,cry,consolability(FLACC)measurement at 3-hour intervals.Tramadol was considered ineffective if the FLACC score was higher than 4 in 10 at anytime.In phase 1,seven dose levels were used within the range 0.1-0.4 mg·kg^(-1)·h^(-1).Phase 1 was insufficient to identify the MED,and we increased the dose to 0.4-0.8 mg·kg^(-1)·h^(-1) in phase 2.Phase 2 was insufficient to identify the MED.In phase 3,local anesthetic wound infiltration was introduced,and the tramadol dose levels tested were the same as in phase 1.The successful analgesia probability of tramadol 0.4 mg·kg^(-1)·h^(-1) was 82.1%(95%CI,0.742-0.925)in phase 1.In phase 2,it was 84.7%(95%CI,0.789-0.991)with the dose 0.8 mg·kg^(-1)·h^(-1).Phase 1 and phase 2 were insufficient to identify the MED.In phase 3,the successful analgesia probability for dose 0.35 mg·kg^(-1)·h^(-1) was 96.7%(95%CI,0.853-0.997).We have demonstrated that tramadol provides insufficient analgesia for surgeries considered to cause moderate-to-severe postoperative pain in infants if used as the sole analgesic,and that local anesthetic wound infiltration enhances the efficacy of tramadol.

A novel intravenous general anesthetic—emulsified isoflurane:from bench to bedside

Application of volatile anesthetics greatly alters modern medicine.There are obvious advantages of volatile anesthetics such as strong anesthetic potency,rapid onset and elimination through respiration system.Isoflurane is one of the most widely used volatile anesthetics in clinic.Emulsified isoflurane,the emulsion of isoflurane,is a novel intravenous general anesthetic.With the development of emulsified isoflurane in the past fifteen years,its utility has spread from intravenous general anesthesia to various fields including regional anesthesia,organ protection,as well as anesthetic pharmacological study.In this review,we will summarize literatures of emulsified isoflurane about its history,clinical application and future potential utility in the above mentioned fields.

Esophageal pulse oximetry is more accurate and detects hypoxemia earlier than conventional pulse oximetry during general anesthesia

The esophagus is perfused directly by prominent arteries and may provide a more consistent tissue source for pulse oximetry.The goal of this study was to evaluate the sensitivity and accuracy of an esophageal pulse oximetry probe on patients during controlled hypoxemia in comparison to measurements obtained with conventional pulse oximetry(SpulseO_(2)).Forty-five ASA Ⅰ-Ⅱ adult patients were included in this prospective observational study.Nellcor digital oximetric probes were placed on finger tips for SpulseO_(2) before anesthesia.After tracheal intubation,an esophageal probe was placed in the lower segment of the esophagus for esophageal oximetric monitoring(SoesO_(2)).All patients were disconnected from the breathing circuit to establish a controlled hypoxemia,and were re-connected to the breathing circuit and ventilated with 100% oxygen immediately when SoesO_(2) dropped to 90%.Matched SoesO_(2) and SpulseO_(2) readings were recorded when SoesO_(2) measurements were at 100%,95%,90% and the lowest reading.The time for SoesO_(2) and SpulseO_(2) to drop from 100% to 95%,90% and return to 100% was recorded.Oxygen saturation from arterial blood samples(SartO_(2))was also measured at each time point respectively.The linear correlation coefficient of the regression analysis between SartO_(2) and SoesO_(2) was 0.954.The mean±2SD of the difference was 0.3%±4.3% for SoesO_(2) vs.SartO_(2) and 6.8%±5.6% for SpulseO_(2) vs.SartO_(2)(P<0.001).The 95% confidence interval for the absolute difference between SoesO_(2) and SartO_(2) was 0.3% to 0.7% and 6.2% to 7.4%between SpulseO_(2) and SartO_(2).The time to reach 90% saturation measured with SoesO_(2) was approximately 94 seconds earlier than the SpulseO_(2)(P<0.001).In conclusion,SoesO_(2) is more accurate and enables earlier detection of hypoxemia when compared to conventional pulse oximetry during hypoxemia for patients undergoing general anesthesia.

Oral nanoparticles containing naringenin suppress atherosclerotic progression by targeting delivery to plaque macrophages

Atherosclerosis is the main cause of ischemic stroke and myocardial infarction diseases.Nanoparticles have shown unique benefits for atherosclerosis treatment by targeting the lesional macrophages of plaques.However,most of the nanocarriers are administered intravenously,which is inconvenient and may cause complications.Herein,we developed an oral lipid-polymer based nanoparticles(FA-LNPs)decorated with folic acid,which can not only effectively overcome intestinal mucosal-epithelial barrier by increasing the transmembrane transport through intestinal epithelial and the accumulation in Peyer’s patches but also actively target to the aortic plaque sites and accumulate in lesional macrophages.Subsequently,naringenin(Nrg),one of the antiinflammation drugs,was designed to be the oral nanomedicine(FA-LNPs/Nrg)for the first time via the encapsulation of FALNPs.FA-LNPs/Nrg presented highly anti-atherosclerotic efficacy.After the atherosclerotic ApoE−/−mice were treated by FALNPs/Nrg via oral administration for three months,the aortic lesion area,plaque area,and necrotic core area of the aortic root were significantly decreased.Meanwhile,the lipid-related blood parameters recovered to normal levels.Our study provides a promising approach to atherosclerosis treatment based on the novel oral targeting delivery system.

Individualized red-cell transfusion strategy for non-cardiac surgery in adults:a randomized controlled trial

Background:Red-cell transfusion is critical for surgery during the peri-operative period;however,the transfusion threshold remains controversial mainly owing to the diversity among patients.The patient’s medical status should be evaluated before making a transfusion decision.Herein,we developed an individualized transfusion strategy using the West-China-Liu’s Score based on the physiology of oxygen delivery/consumption balance and designed an open-label,multicenter,randomized clinical trial to verify whether it reduced red cell requirement as compared with that associated with restrictive and liberal strategies safely and effectively,providing valid evidence for peri-operative transfusion.Methods:Patients aged>14 years undergoing elective non-cardiac surgery with estimated blood loss>1000 mL or 20%blood volume and hemoglobin concentration<10 g/dL were randomly assigned to an individualized strategy,a restrictive strategy following China’s guideline or a liberal strategy with a transfusion threshold of hemoglobin concentration<9.5 g/dL.We evaluated two primary outcomes:the proportion of patients who received red blood cells(superiority test)and a composite of in-hospital complications and all-cause mortality by day 30(non-inferiority test).Results:We enrolled 1182 patients:379,419,and 384 received individualized,restrictive,and liberal strategies,respectively.Approximately 30.6%(116/379)of patients in the individualized strategy received a red-cell transfusion,less than 62.5%(262/419)in the restrictive strategy(absolute risk difference,31.92%;97.5%confidence interval[CI]:24.42-39.42%;odds ratio,3.78%;97.5%CI:2.70-5.30%;P<0.001),and 89.8%(345/384)in the liberal strategy(absolute risk difference,59.24%;97.5%CI:52.91-65.57%;odds ratio,20.06;97.5%CI:12.74-31.57;P<0.001).No statistically significant differences were found in the composite of in-hospital complications and mortality by day 30 among the three strategies.Conclusion:The individualized red-cell transfusion strategy using the West-China-Liu’s Score reduced red-cell transfusion without increasing in-hospital complications and mortality by day 30 when compared with restrictive and liberal strategies in elective non-cardiac surgeries.Trial registration:ClinicalTrials.gov,NCT01597232.

Poly(I:C)preconditioning protects the heart against myocardial ischemia/reperfusion injury through TLR3/PI3K/Akt-dependent pathway

Emerging evidence suggests that Toll-like receptors(TLRs)ligands pretreatment may play a vital role in the progress of myocardial ischemia/reperfusion(I/R)injury.As the ligand of TLR3,polyinosinic-polycytidylic acid(poly(I:C)),a synthetic double-stranded RNA,whether its preconditioning can exhibit a cardioprotective phenotype remains unknown.Here,we report the protective effect of poly(I:C)pretreatment in acute myocardial I/R injury by activating TLR3/PI3K/Akt signaling pathway.Poly(I:C)pretreatment leads to a significant reduction of infarct size,improvement of cardiac function,and downregulation of inflammatory cytokines and apoptotic molecules compared with controls.Subsequently,our data demonstrate that phosphorylation of TLR3 tyrosine residue and its interaction with PI3K is enhanced,and protein levels of phospho-PI3K and phospho-Akt are both increased after poly(I:C)pretreatment,while knock out of TLR3 suppresses the cardioprotection of poly(I:C)preconditioning through a decreased activation of PI3K/Akt signaling.Moreover,inhibition of p85 PI3K by the administration of LY294002 in vivo and knockdown of Akt by siRNA in vitro significantly abolish poly(I:C)preconditioning-induced cardioprotective effect.In conclusion,our results reveal that poly(I:C)preconditioning exhibits essential protection in myocardial I/R injury via its modulation of TLR3,and the downstream PI3K/Akt signaling,which may provide a potential pharmacologic target for perioperative cardioprotection.