Comparison of two supplemental oxygen methods during gastroscopy with propofol mono-sedation in patients with a normal body mass index

BACKGROUND Hypoxemia due to respiratory depression and airway obstruction during upper gastrointestinal endoscopy with sedation is a common concern.The Wei nasal jet tube(WNJT)is a new nasopharyngeal airway with the ability to provide supraglottic jet ventilation and oxygen insufflation via its built-in wall channel.The available evidence indicates that with a low oxygen flow,compared with nasal cannula,the WNJT does not decrease the occurrence of hypoxemia during upper gastrointestinal endoscopy with propofol sedation.To date,there has been no study assessing the performance of WNJT for supplemental oxygen during upper gastrointestinal endoscopy with sedation when a moderate oxygen flow is used.AIM To determine whether the WNJT performs better than the nasal prongs for the prevention of hypoxemia during gastroscopy with propofol mono-sedation when a moderate oxygen flow is provided in patients with a normal body mass index.METHODS This study was performed in 291 patients undergoing elective gastroscopy with propofol mono-sedation.Patients were randomized into one of two groups to receive either the WNJT(WNJT group,n=147)or the nasal cannula(nasal cannula group,n=144)for supplemental oxygen at a 5-L/min flow during gastroscopy.The lowest SpO2 during gastroscopy was recorded.The primary endpoint was the incidence of hypoxemia or severe hypoxemia during gastroscopy.RESULTS The total incidence of hypoxemia and severe hypoxemia during gastroscopy was significantly decreased in the WNJT group compared with the nasal cannula group(P=0.000).The lowest median SpO2 during gastroscopy was significantly higher(98%;interquartile range,97-99)in the WNJT group than in the nasal cannula group(96%;interquartile range,93-98).Epistaxis by device insertion in the WNJT group occurred in 7 patients but stopped naturally without any treatment.The two groups were comparable in terms of the satisfaction of physicians,anesthetists and patients.CONCLUSION With a moderate oxygen flow,the WNJT is more effective for the prevention of hypoxemia during gastroscopy with propofol mono-sedation compared with nasal prongs,but causing slight epistaxis in a few patients.

Prospective, randomized comparison of two supplemental oxygen methods during gastro-scopy with propofol mono-sedation in obese patients

BACKGROUND Hypoxemia is a common complication in obese patients during gastroscopy with sedation.The Wei nasal jet tube(WNJT)is a new special nasopharyngeal airway with the ability to provide supraglottic jet ventilation and oxygen insufflation via its built-in wall channels.The aim of this study was to compare the efficacy and safety of the WNJT vs a nasal cannula for supplemental oxygen during gastroscopy with propofol mono-sedation in obese patients.AIM To compare the efficacy and safety of the WNJT vs a nasal cannula for supplemental oxygen during gastroscopy with propofol mono-sedation in obese patients.METHODS A total of 103 obese patients with a body mass index of 30 kg/m2 or more undergoing elective gastroscopy under propofol mono-sedation were randomly assigned to receive supplemental oxygen at 5 L/min through either a WNJT(WNJT group,n=51)or a nasal cannula(nasal cannula group,n=52).The lowest pulse oxygen saturation(SpO2)and mild and severe hypoxemia during gastroscopy were recorded.The primary outcome was the incidence of hypoxemia.RESULTS The lowest SpO2 during gastroscopy with propofol mono-sedation was significantly increased in the WNJT group compared with the nasal cannula group.The incidence of mild hypoxemia and total incidence of hypoxemia were significantly lower in the WNJT group than in the nasal cannula group.Other than a higher incidence of epistaxis in the WNJT group,the occurrence of adverse events was similar between the devices.While neither device demonstrated a statistically significant difference in satisfaction among patients,the WNJT did result in improved satisfaction among anesthetists and physicians.CONCLUSION During gastroscopy with propofol mono-sedation in obese patients,the WNJT,when compared with a nasal cannula for supplemental oxygen,can significantly reduce the occurrence of hypoxemia and improve both arterial oxygenation and satisfaction among anesthetists and physicians.The use of the WNJT may,however,lead to epistaxis in a few patients.In view of this clinically acceptable risk-benefit ratio,the WNJT may be recommended as an alternative tool for supplemental oxygen for the prevention of hypoxemia during gastroscopy with propofol mono-sedation in obese patients.

Determination of the ED95 of intranasal sufentanil combined with intranasal dexmedetomidine for moderate sedation during endoscopic ultrasonography

BACKGROUND Sedation during endoscopic ultrasonography(EUS)poses many challenges and moderate-to-deep sedation are often required.The conventional method to preform moderate-to-deep sedation is generally intravenous benzodiazepine alone or in combination with opioids.However,this combination has some limitations.Intranasal medication delivery may be an alternative to this sedation regimen.AIM To determine,by continual reassessment method(CRM),the minimal effective dose of intranasal sufentanil(SUF)when combined with intranasal dexmedetomidine(DEX)for moderate sedation of EUS in at least 95%of patients(ED95).METHODS Thirty patients aged 18-65 and scheduled for EUS were recruited in this study.Subjects received intranasal DEX and SUF for sedation.The dose of DEX(1μg/kg)was fixed,while the dose of SUF was assigned sequentially to the subjects using CRM to determine ED95.The sedation status was assessed by modified observer’s assessment of alertness/sedation(MOAA/S)score.The adverse events and the satisfaction scores of patients and endoscopists were recorded.RESULTS The ED95 was intranasal 0.3μg/kg SUF when combined with intranasal 1μg/kg DEX,with an estimated probability of successful moderate sedation for EUS of 94.9%(95%confidence interval:88.1%-98.9%).When combined with intranasal 1μg/kg DEX,probabilities of successful moderate sedation at each dose level of intranasal SUF were as follows:0μg/kg SUF,52.8%;0.1μg/kg SUF,75.4%;0.2μg/kg SUF,89.9%;0.3μg/kg SUF,94.9%;0.4μg/kg SUF,98.0%;0.5μg/kg SUF,99.0%.CONCLUSION The ED95 needed for moderate sedation for EUS is intranasal 0.3μg/kg SUF when combined with intranasal 1μg/kg DEX,based on CRM.

Is low postoperative cholesterol level really an independent risk factor of adverse outcomes after living donor liver transplantation?

To the Editor:We read with great interest the article by Yang et al.[1]evaluating the effects of postoperative serum total cholesterol(sTC)changes on early allograft dysfunction and survival after living donor liver transplantation(LDLT).By the multivariate regression analysis,they showed that patients with sTC<1.42 mmol/L on postoperative day 3 had 4.08-fold and 2.72-fold greater risks of developing allograft dysfunction and 90-day mortality,and patients with sTC<1.42 mmol/L had poorer overall recipient and graft survival rates at 1-,3-,and 5-year compared with those with sTC≥1.42 mmol/L.Thus,they concluded that postoperative sTC<1.42 mmol/L is an independent risk factor of short-and long-term adverse outcomes after LDLT.However,this is a retrospective study,which can introduce a number of potential confounders.Other than the limitations described in discussion section,we noted that some methodological issues seem important to avoid any optimistic interpretation or misinterpretation of results.

Perioperative transcutaneous electrical acupoint stimulation for improving postoperative gastrointestinal function:A randomized controlled trial

Background:Postoperative gastrointestinal dysfunction(PGD)is one of the most common complications in patients undergoing major abdominal surgery.Acupuncture has been used widely in gastrointestinal diseases due to its effectiveness and minimally invasive nature.Objective:This study evaluated the efficacy of using transcutaneous electrical acupoint stimulation(TEAS)during the surgery and postoperative recovery in patients with gastric and colorectal surgery for improving postoperative gastrointestinal function.Design,setting,participants and interventions:A total of 280 patients undergoing abdominal surgery were stratified by type of surgery(i.e.,gastric or colorectal surgery)and randomly allocated into the TEAS group(group T)or the sham group(group S).Patients in group T received TEAS at LI4,PC6,ST36 and ST37.Patients in group S received pseudo-TEAS at sham acupoints.The stimulation was given from 30 min before anesthesia until the end of surgery.The same treatment was performed at 9 am on the 1st,2nd and 3rd days after surgery,until the recovery of flatus in patients.Main outcome measures:The primary outcome was the time to the first bowel motion,as detected by auscultation.The secondary outcomes included the first flatus and ambulation time,changes of perioperative substance P(SP),incidence of PGD,postoperative pain,postoperative nausea and vomiting(PONV)and some economic indicators.Results:The time to first bowel motion,first flatus and first ambulation in group T was much shorter than that in group S(P<0.01).In patients undergoing colorectal surgery,the concentration of SP was lower in group T than in group S on the third day after the operation(P<0.05).The average incidence of PGD in all patients was 25%,and the frequency of PGD was significantly lower in group T than in group S(18.6%vs.31.4%,respectively;P<0.05).TEAS treatment(odds ratio=0.498;95%confidence interval:0.232–0.786)and type of surgery were relevant factors for the development of PGD.Postoperative pain score and PONV occurrence were significantly lower in group T(P<0.01).Postoperative hospitalization days and the resulting cost to patients were greatly reduced in the TEAS group(P<0.01).Conclusion:Perioperative TEAS was able to promote the recovery of postoperative gastrointestinal function,reduce the incidence of PGD and PONV.The concentration of SP was decreased by TEAS treatment,which indicates that the brain-gut axis may play a role in how TEAS regulates gastrointestinal function.Trial registration:Chinese Clinical Trial Registry,Chi CTR1900023263.

Comparing the effects of different drugs on postoperative cognitive dysfunction in elderly patients

To the Editor:In a randomized controlled preliminary trial comparing effects of propofol,dexmedetomidine,and midazolam on postoperative cognitive dysfunction(POCD)in elderly patients undergoing hip or knee arthroplasty with combined spinal-epidural anesthesia,Li et al[1]showed that intraoperative sedation with propofol compared to dexmedetomidine can significantly decrease risk of POCD.Given that POCD is associated with major adverse consequences,for example,an increased mortality rate,reduced quality of life,and delayed long-term recovery,[2]their findings have potential implications.However,we note that this finding is totally different from the results of a recent large randomized controlled study in elderly patients undergoing hip arthroplasty with the peripheral nerve block,in which patients sedated with dexmedetomidine have a lower risk of POCD than those sedated with propofol.

A feasibility study of jaw thrust as an indicator assessing adequate depth of anesthesia for insertion of supraglottic airway device in morbidly obese patients

Background:Jaw thrust has been proven as a useful test determining adequate depth of anesthesia for successful insertion of supraglottic airway device (SAD) in normal adults and children receiving intra-venous or inhalational anesthesia induction.This prospective observational study aimed to determine the feasibility and validity of this test when using as an indicator assessing adequate depth of anesthesia for successful insertion of SAD in spontaneously breathing morbidly obese patients receiving sevoflurane inhalational induction.Methods:Thirty morbidly obese patients with a body mass index 40 to 73 kg/m2 undergoing bariatric surgery in Beijing Friendship Hospital from October 2018 to January 2019 were included in this study.After adequate pre-oxygenation,5% sevoflurane was inhaled and inhalational concentration of sevoflurane was increased by 1% every 2 min.After motor responses to jaw thrust disappeared,a SAD was inserted and insertion conditions were graded.The anatomic position of SAD was assessed using a fiberoptic bronchoscope.Results:The SAD was successfully inserted at the first attempt in all patients.Insertion conditions of SAD were excellent in nine patients (30%) and good in 21 patients (70%),respectively.The fiberoptic views of SAD position were adequate in 28 patients (93%).Conclusions:Jaw thrust test is a reliable indicator determining adequate anesthesia depth of sevoflurane inhalational induction for successful insertion of SAD in spontaneously breathing morbidly obese patients.

New nomenclature of peri-operative cognitive impairments: possible impacts on further practice and research

Peri-operative neurocognitive disorders (PND) is a new term recommended by an international,multidisciplinary group named as Nomenclature Consensus Working Group including experts from multiple disciplines such as anesthesiology,neurology,geriatrics,psychiatry,neuropsychology,surgery,and psychology.It is a comprehensive term for cognitive impairments identified in the perioperative period.The recommendation of this new nomenclature has been published in several influential journals simultaneously in November 2018.[1-6] It is a tremendous change in the field of peri-operative cognitive impairments.Therefore,it is necessary to know the reasons and purposes of this new nomenclature,differences between old and new nomenclatures,and the possible impacts of new nomenclature on clinical and basic researches of peri-operative cognitive impairments in the future.

Comparing Postoperative Pain After Laparoscopic Cholecystectomy

To the Editor:In a recent article published by Guo et al.[1] who compared postoperative pain after traditional and single-incision laparoscopic cholecystectomy (SILC),it was showed that SILC resulted in a slightly less immediate postoperative pain,but pain scores at 24 hours,7 days,and 1-6 months after surgery were not different between the two operations.Many things of this study were well done.The authors used a double-blinded,randomized,and controlled design.

How to Initiate and Perform Simulation-based Airway Management Training More Effectively and Efficiently in China？

INTRODUCTION While airway management is a fundamental skill set for many healthcare professionals, the difficult airway management has long been recognized as one of the most challenging tasks facing healthcare providers.As yet, failure to properly manage airway conditions remains a significant source of patients' morbidity and mortality.[1] To avoid or reduce medical errors and improve patient safety and outcomes, training for healthcare providers for airway management skills is essential.

Establishing a risk prediction model for acute kidney injury: methodology is important

To the Editor:By a retrospective study including 1124 hospitalized patients diagnosed with acute myocardial infarction(AMI),Wang et al[1] showed that the independent risk factors for acute kidney injury(AKI)were age>60 years,hypertension,chronic kidney disease(CKD),Killip class≥3,extensive anterior myocardial infarction,use of furosemide,non-use of angiotensin-converting enzyme inhibitors(ACEI)/angiotensin receptor blocker(ARB),and these factors could provide a prediction model"with good discriminative ability for the development of AKI.Given that AKI has been significantly associated with morbidity and mortality of patients with AMI,[2]their findings have potential clinical implications.Other than the limitations described by authors in the discussion;however,we noted some methodological issues in their study that needed further clarifications.

Anesthesia-induced developmental neurotoxicity in children: past, present, and future

Since 1999, a large body of evidence from various animal models indicates a link between anesthesia exposure in early stage of life and subsequent neurodevelopmental impairments1namely, almost all commonly used intravenous and inhalational anesthetics, including gamma- aminobutyric acid agonists and N-methyl-D-aspartate antagonists, can induce dose- and age-dependent neuronal apoptosis and death in vitro. Moreover, abundant data from nematodes to primate animals have shown a variety of anatomic and neurodevelopmental sequelae from anesthesia exposure in young animals.[2,3] In the rodents, the most prominent manifestations of anesthesia-induced developmental neurotoxicity (AIDN) are often observed at post-natal day 7 .

A left-side channel design improving insertion of gastric tube via the supraglottic airway device

To the Editor:The supraglottic airway device (SAD) with an additional gastric drainage channel may be beneficial for patients needing gastric decompression during surgery, such as laparoscopic cholecystectomy and cesarean delivery. Furthermore, addition of gastric drainage channel is a typical feature of second-generation SAD. However, all of second-generation SADs have a gastric tube channel opening at the center of the distal tip. Such a design may cause some difficulty for insertion of the gastric tube if there is an inadequate position of the device tip in the upper esophageal aperture. In normal anatomy, the upper esophageal aperture is actually inclined to the left side of the trachea. Thus, we inferred that it should be much easier to insert a gastric tube into the esophagus, if the gastric drainage channel is placed at the left side of the SAD tip.

A safe strategy for anesthesia induction and airway management in morbidly obese patients

To the Editor:Morbidly obese patients are known to be difficult for facemask ventilation and tracheal intubation,leading to an increased risk for a "cannot intubate cannot ventilate" situation.Awake tracheal intubation is often considered as one of the safest strategies for anesthesia induction and airway management in patients with known or predicted difficult airways,but the technique itself is an uncomfortable procedure.