Efficacy and safety of alfentanil hydrochloride injection in general anesthesia: A multicenter, double-blind, controlled study / 中国药理学通报

Aim To investigate the effectiveness and safety of alfentanil in general anesthesia.Methods In this study, a multicenter randomized double-blind con¬trolled study was conducted.A total of 352 subjects were selected and randomly assigned to fentanyl group (group A, n =176) and alfentanil group (group 15, n = 176).Anesthesia induction: intravenous midazolam 0.03 mg • kg-1 + fentanyl 25 p.g • kg"'(group A) or alfentanil 4 p,g • kg-1 ( group 15) + propofol 2 mg • kg"1 + rocuronium 0.8 mg • kg"1.Sevoflurane + fent¬anyl ( group A ) or alfentanil ( group B ) + rocuronium were used for anesthesia.The vital signs of patients re¬covery time and extuhation time, anesthesia-related complications and the use of related remedial drugs during anesthesia induction and maintenance were compared between the two groups.Results During the induction and maintenance period of anesthesia, alfentanil and fentanyl could equally effectively inhibit the stress response induced by endotracheal intubation and surgical stimulation.Alfentanil also showed more effective inhibition on stress response induced by endo¬tracheal intubation and surgical stimulation than that of fentanyl ( P < 0.05 ) .However, there was no signifi¬cant difference in the incidence of intraoperative hypo¬tension and hypertension and the time of anesthesia re¬covery and extubation between the two groups.Conclu¬sions Both alfentanil and fentanyl can effectively in¬hibit the stress response induced by surgical stimulation and could be safely used in general anesthesia in sur¬gery.Alfentanil has more advantages in maintaining the stability of blood pressure and heart rate during an¬esthesia induction and maintenance.

Perioperative transcutaneous electrical acupoint stimulation for improving postoperative gastrointestinal function: A randomized controlled trial / 中西医结合学报

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, ChiCTR1900023263.

A feasibility study of jaw thrust as an indicator assessing adequate depth of anesthesia for insertion of supraglottic airway device in morbidly obese patients / 中华医学杂志(英文版)

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.@*Clinical trial registration@#ChiCTR1800016868; http://www.chictr.org.cn/showproj.aspx?proj=28646.

A feasibility study of jaw thrust as an indicator assessing adequate depth of anesthesia for insertion of supraglottic airway device in morbidly obese patients / 中华医学杂志(英文版)

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/m 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.@*CLINICAL TRIAL REGISTRATION@#ChiCTR1800016868; http://www.chictr.org.cn/showproj.aspx?proj=28646.

Feasibility Analysis of Oxygen-Glucose Deprivation-Nutrition Resumption on H9c2 Cells Models of Myocardial Ischemia-Reperfusion Injury / 中华医学杂志(英文版)

<p><b>Background</b>Oxygen-glucose deprivation-nutrition resumption (OGD-NR) models on H9c2 cells are commonly used in vitro models of simulated myocardial ischemia-reperfusion injury (MIRI), but no study has assessed whether these methods for establishing in vitro models can effectively imitate the characteristics of MIRI in vivo. This experiment was designed to analyze the feasibility of six OGD-NR models of MIRI.</p><p><b>Methods</b>By searching the PubMed database using the keywords "myocardial reperfusion injury H9c2 cells," we obtained six commonly used OGD-NR in vitro models of MIRI performed on H9c2 cells from more than 400 published papers before January 30, 2017. For each model, control (C), simulated ischemia (SI), and simulated ischemia-reperfusion (SIR) groups were assigned, and cell morphology, lactate dehydrogenase (LDH) release, adenosine triphosphate (ATP) levels, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and inflammatory cytokines were examined to evaluate the characteristics of cell injury. Subsequently, a coculture system of cardiomyocyte-endothelial-macrophage was constructed. The coculture system was dealt with SI and SIR treatments to test the effect on cardiomyocytes survival.</p><p><b>Results</b>For models 1, 2, 3, 4, 5, and 6, SI treatment caused morphological damage to cells, and subsequent SIR treatment did not cause further morphological damage. In the models 1, 2, 3, 4, 5 and 6, LDH release was significantly higher in the SI groups than that in the C group (P < 0.05), and was significantly lower in the SIR groups than that in the SI groups (P < 0.05), except for no significant differences in the LDH release between C, SI and SIR groups in model 6 receiving a 3-h SI treatment. In models 1, 2, 3, 4, 5, and 6, compared with the C group, ATP levels of the SI groups significantly decreased (P < 0.05), ROS levels increased (P < 0.05), and MMP levels decreased (P < 0.05). Compared with the SI group, ATP level of the SIR groups was significantly increased (P < 0.05), and there was no significant ROS production, MMP collapse, and over inflammatory response in the SIR groups. In a coculture system of H9c2 cells-endothelial cells-macrophages, the proportion of viable H9c2 cells in the SIR groups was not reduced compared with the SI groups.</p><p><b>Conclusion</b>All the six OGD-NR models on H9c2 cells in this experiment can not imitate the characteristics of MIRI in vivo and are not suitable for MIRI-related study.</p>

Effect of Autophagy Inhibition on the Protection of Ischemia Preconditioning against Myocardial Ischemia/Reperfusion Injury in Diabetic Rats / 中华医学杂志(英文版)

<p><b>Background</b>Ischemia preconditioning (IPC) remains the most powerful intervention of protection against myocardial ischemia/reperfusion injury (IRI), but diabetes can weaken or eliminate its cardioprotective effect and detailed mechanisms remain unclear. In this study, we aimed to explore whether changes of autophagy in the diabetic condition are attributable to the decreased cardioprotective effect of IPC.</p><p><b>Methods</b>Sixty diabetic male Sprague-Dawley rats were randomly divided into the control (C), IRI, rapamycin (R), wortmannin (W), rapamycin + IPC (R + IPC), and wortmannin + IPC (W + IPC) groups. The in vivo rat model of myocardial IRI was established by ligaturing and opening the left anterior descending coronary artery via the left thoracotomy. Durations of ischemia and reperfusion are 30 min and 120 min, respectively. Blood samples were taken at 120 min of reperfusion for measuring serum concentrations of troponin I (TnI) and creatine kinase isoenzyme MB (CK-MB) using the enzyme-linked immunosorbent assay. The infarct size was assessed by Evans blue and triphenyltetrazolium chloride staining. The expressions of LC3-II, beclin-1, phosphoinositide 3-kinase (PI3K), mammalian target of rapamycin (mTOR), and P-Akt/Akt ratio in the ischemic myocardium were assessed by Western blotting.</p><p><b>Results</b>Compared to the IRI group, infarct size (56.1% ± 6.1% vs. 75.4 ± 7.1%, P < 0.05), serum cTnI (0.61 ± 0.21 vs. 0.95 ± 0.26 ng/ml, P < 0.05), and CK-MB levels (6.70 ± 1.25 vs. 11.51 ± 2.35 ng/ml, P < 0.05) obviously decreased in the W + IPC group. Compared with the C group, myocardial expressions of LC3-II (0.46 ± 0.04 and 0.56 ± 0.04 vs. 0.36 ± 0.04, P < 0.05) and beclin-1 (0.34 ± 0.08 and 0.38 ± 0.07 vs. 0.24 ± 0.03, P < 0.05) evidently increased, and myocardial expressions of mTOR (0.26 ± 0.08 and 0.25 ± 0.07 vs. 0.38 ± 0.06, P < 0.05), PI3K (0.29 ± 0.04 and 0.30 ± 0.03 vs. 0.38 ± 0.02, P < 0.05), and P-Akt/Akt ratio (0.49 ± 0.10 and 0.48 ± 0.06 vs. 0.72 ± 0.07, P < 0.05) markedly decreased in the IRI and R groups, indicating an increased autophagy. Compared with the IRI group, myocardial expression of beclin-1 (0.26 ± 0.03 vs. 0.34 ± 0.08, P < 0.05) significantly decreased, and myocardial expressions of mTOR (0.36 ± 0.04 vs. 0.26 ± 0.08, P < 0.05), PI3K (0.37 ± 0.03 vs. 0.29 ± 0.04, P < 0.05), and P-Akt/Akt ratio (0.68 ± 0.05 vs. 0.49 ± 0.10, P < 0.05) increased obviously in the W + IPC group, indicating a decreased autophagy.</p><p><b>Conclusions</b>Increased autophagy in the diabetic myocardium is attributable to decreased cardioprotection of IPC, and autophagy inhibited by activating the PI3K-Akt-mTOR signaling pathway can result in an improved protection of IPC against diabetic myocardial IRI.</p>

Current Evidences for the Use of UEscope in Airway Management / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>UEscope is a new angulated videolaryngoscope (VL). This review aimed to describe the features of UEscope and provide clinical evidences regarding the efficacy and safety of this video device in adult tracheal intubation and its roles in airway management teaching.</p><p><b>DATA SOURCES</b>The Wan Fang Data, CNKI, PubMed, Embase, Cochrane Library, and Google Scholar were searched for relevant English and Chinese articles published up to January 15, 2017, using the following keywords: "HC video laryngoscope", "UE videolaryngoscope", "video laryngoscope", and "videolaryngoscopy".</p><p><b>STUDY SELECTION</b>Human case reports, case series, observable studies, and randomized controlled clinical trials were included in our search. The results of these studies and their reference lists were cross-referenced to identify a common theme.</p><p><b>RESULTS</b>UEscope features the low-profile portable design, intermediate blade curvatures, all-angle adjustable monitor, effective anti-fog mechanisms, and built-in video recording function. During the past 5 years, there have been a number of clinical studies assessing the application and roles of UEscope in airway management and education. As compared with direct laryngoscope, UEscope improves laryngeal visualization, decreases intubation time (IT), and increases intubation success rate in adult patients with normal and difficult airways. These findings are somewhat different from the previous results regarding the other angulated VLs; they can provide an improved laryngeal view, but no conclusive benefits with regard to IT and intubation success rate. Furthermore, UEscope has extensively been used for intubation teaching and shown a number of advantages.</p><p><b>CONCLUSIONS</b>UEscope can be used as a primary intubation tool and may provide more benefits than other VLs in patients with normal and difficult airways. However, more studies with large sample are still needed to address some open questions about clinical performance of this new VL.</p>

Ischemic preconditioning produces more powerful anti-inflammatory and cardioprotective effects than limb remote ischemic postconditioning in rats with myocardial ischemia-reperfusion injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Both ischemic preconditioning (IPC) and limb remote ischemic postconditioning (LRIPOC) have been shown to possess significantly different cardioprotective effects against the myocardial ischemia reperfusion injury (IRI), but no study has compared the anti-inflammatory effects of IPC and LRIPOC during myocardial IRI process. We hypothesized that IPC and LRIPOC would produce different anti-inflammatory effects in an in vivo rat model with myocardial IRI.</p><p><b>METHODS</b>Eighty rats were randomly allocated into four equal groups: sham group, IRI group, IPC group and LRIPOC group. In 10 rats randomly selected from each group, serum levels of TNF-α, HMGB1, ICAM1, IL-1, IL-6 and IL-10 were assessed, and infarct size was determined. In another 10 rats of each group, myocardial levels of TNF-α, HMGB1, ICAM1, IL-1, IL-6 and IL-10 in both ischemic and non-ischemic regions were measured.</p><p><b>RESULTS</b>The infarct size was significantly lower in IPC and LRIPOC groups than in IRI group. The serum and myocardial levels of pro-inflammatory cytokines including TNF-α, HMGB1, ICAM1, IL-1 and IL-6 during reperfusion were significantly reduced in IPC and LRIPOC groups compared to IRI group. As compared to the IPC group, infarct size, serum level of TNF-α at 60 minutes of reperfusion, serum levels of HMGB1 and ICAM1 at 120 minutes of reperfusion, myocardial levels of TNF-α, ICAM1, IL-1 and IL-6 in the ischemic region, myocardial levels of ICAM1, IL-1 and IL-6 in the non-ischemic region were significantly increased in the LRIPOC group.</p><p><b>CONCLUSIONS</b>In the rats with myocardial IRI, IPC produces more powerful inhibitory effects on local myocardial and systemic inflammatory responses than LRIPOC. This may be partly attributed to more potent cardioprotection produced by IPC.</p>

Combined postconditioning with ischemia and α7nAChR agonist produces an enhanced protection against rat myocardial ischemia reperfusion injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Inflammation is one of important mechanisms for myocardial ischemia reperfusion injury (IRI). Ischemia postconditioning (IPOC) can protect the heart against IRI by inhibiting inflammation, but its cardioprotection is weaker than that of ischemia preconditioning. Recently, the α7 subunit-containing nicotinic acetylcholine receptor (α7nAChR) agonist has shown anti-inflammatory effects in many diseases related to inflammation. This randomized controlled experiment was designed to evaluate whether combined postconditioning with IPOC and the α7nAChR agonist could produce an enhanced cardioprotection in a rat in vivo model of acute myocardial IRI.</p><p><b>METHODS</b>Fifty Sprague-Dawley rats were randomly divided into five equal groups: sham group, control group, IPOC group, α7nAChR agonist postconditioning group (APOC group) and combined postconditioning with IPOC and α7nAChR agonist group (combined group). Hemodynamic parameters were recorded during the periods of ischemia and reperfusion. Serum concentrations of troponin I (TnI), tumor necrosis factor α (TNF-α) and high-mobility group box 1 (HMGB-1) at 180 minutes after reperfusion were assayed in all groups. At the end of the experiment, the infarct size was assessed from excised hearts by Evans blue and triphenyl tetrazolium chloride staining.</p><p><b>RESULTS</b>As compared to the sham group, the infarct size in the other four groups was significantly increased, serum levels of TnI, TNF-α and HMGB1 in the control group and TNF-α, HMGB1 in the IPOC group were significantly increased. The infarct size and serum concentrations of TNF-α, HMGB1 and TnI in the IPOC, APOC and combined groups were significantly lower than those in the control group. As compared to the IPOC group, the infarct size in the combined group was significantly decreased, serum concentrations of TnI, TNF-α and HMGB1 in the APOC and combined groups were significantly reduced. Although the infarct size was significantly smaller in the combined group than in the APOC group, serum levels of TNF-α and HMGB1 were significantly higher in the combined group than in the APOC group.</p><p><b>CONCLUSIONS</b>In a rat in vivo model of acute myocardial IRI, combined postconditioning with IPOC and the α7nAChR agonist can produce enhanced protection against myocardial IRI by increasing the anti-inflammatory effect.</p>

Remote ischemia conditioning-an endogenous cardioprotective strategy from outside the heart / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>A general review was made of studies involving: (1) The experimental evidence of remote ischemic preconditioning (RIPC) and relative clinical studies, (2) The experimental and clinical evidences of remote ischemic postconditioning (RIPOC), (3) The potential mechanistic pathways underlying their protective effects.</p><p><b>DATA SOURCES</b>The data used in this review were mainly from manuscripts listed in PubMed that were published in English from 1986 to 2010. The search terms were "myocardial ischemia reperfusion injury", "ischemia preconditioning", "ischemia postconditioning", "remote preconditioning" and "remote postconditioning".</p><p><b>STUDY SELECTION</b>(1) Clinical and experimental evidence that both RIPC and RIPOC produce preservation of ischemia reperfusion injury (IRI) of myocardium and other organs, (2) Studies related to the potential mechanisms, by which remote ischemic conditioning protects myocardium against IRI.</p><p><b>RESULTS</b>Both RIPC and RIOPC have been shown to attenuate myocardial IRI in laboratory animals. Also, their cardioprotective effects have appeared in some clinical studies. Except the external, the detailed internal mechanisms of remote ischemic conditioning have been generally described. Through these descriptions better protocols can be developed to provide improved cardioprotective procedures.</p><p><b>CONCLUSIONS</b>Remote ischemic conditioning is an endogenous cardioprotective mechanism from outside the heart that protects against myocardial IRI and represents a general form of inter-organ protection. Remote ischemic conditioning may have an immense impact on clinical practice in the near future.</p>

Comparison of hemodynamic responses to orotracheal intubation with shikani laryngoscope or macintosh direct laryngoscope / 中国医学科学院学报

<p><b>OBJECTIVE</b>To compare the hemodynamic responses to orotracheal intubation using a Shikani Optical Stylet (SOS) laryngoscope or a Macintosh direct laryngoscope (MDLS).</p><p><b>METHODS</b>Totally 41 patients with American Society of Anesthesiologists ASA physical status -aged 20-60 years and scheduled for elective surgery under general anesthesia requiring orotracheal intubation, were randomly allocated to either the SOS group (n=21) or MDLS group (n=20). After an intravenous anesthetic induction the orotracheal intubation was performed using a SOS laryngoscope or a MDLS. Blood pressure and heart rate (HR) were recorded before and after anesthetic induction immediately after intubation, and 5 minutes after intubation. Rate pressure product RPP were calculated.</p><p><b>RESULTS</b>Blood pressures and RPP in both two groups significantly decreased after anesthetic induction (P<0.05) while blood pressures HR, and RPP significantly increased after orotracheal intubation (P<0.05). HR in both groups after intubation were significantly higher than the pre-induction level (P<0.05)and such an increase lasted for 3 min. HR immediately after intubation was also significantly higher in MDLS group than in SOS group (P<0.05); however, such difference was not observed in other time points (P>0.05). In the MDLS group when compared with the occurrence time required for the maximum values of systolic blood pressure (SBP)the occurrence time required for the maximum values of HR after the start of intubation and success of intubation during the observation were significantly delayed (P<0.05). Compared with the MDLS group, the occurrence time required for the maximum values of SBP after the start of intubation and the success of intubation were significantly delayed in the SOS group (P<0.05). The incidences of SBP more than 130% of baseline value and RPP more than 22 000 were not significantly differently(P>0.05). Also, the intubation time was not significantly different (P>0.05).</p><p><b>CONCLUSION</b>The hemodynamic responses to orotracheal intubation is milder in SOS laryngoscope than in MDLS.</p>

Cholinergic anti-inflammatory pathway: a possible approach to protect against myocardial ischemia reperfusion injury / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>A general review was made of studies involving: (1) the concept and mechanism of the cholinergic anti-inflammatory pathway (CAP), (2) the important role of inflammatory response in myocardial ischemia reperfusion (I/R) injury and (3) the evidence and mechanisms by which CAP may provide protection against myocardial I/R injury.</p><p><b>DATA SOURCES</b>The data used in this review were mainly from manuscripts listed in PubMed that were published in English from 1987 to 2009. The search terms were "vagal nerve stimulation", "myocardial ischemia reperfusion injury", "nicotine acetylcholine receptor" and "inflammation".</p><p><b>STUDY SELECTION</b>(1) Clinical and experimental evidence that the inflammatory response induced by reperfusion enhances myocardial I/R injury. (2) Clinical and laboratory evidence that the CAP inhibits the inflammation and provides protection against myocardial I/R injury.</p><p><b>RESULTS</b>The myocardial I/R injury is really an inflammatory process characterized by recruitment of neutrophils into the ischemic myocardium and excessive production of pro-inflammatory cytokines. Because the CAP can modulate the inflammatory response by decreasing the production and release of pro-inflammatory cytokines, it can provide protection against myocardial I/R injury.</p><p><b>CONCLUSIONS</b>The CAP can inhibit the inflammatory response induced by reperfusion and protect against myocardial I/R injury. It represents an exciting opportunity to develop new and novel therapeutics to attenuate the myocardial I/R injury.</p>

Propofol improves cardiac functional recovery after ischemia-reperfusion by upregulating nitric oxide synthase activity in the isolated rat hearts / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There are few studies to assess whether propofol attenuates myocardial ischemia-reperfusion injury via a mechanism related to nitric oxide (NO) route, so we designed this randomized blinded experiment to observe the changes of NO contents, nitric oxide synthase (NOS) activity, NOS contents in the myocardium, and cardiac function in ischemic reperfused isolated rat hearts, and to assess the relation between myocardial NO system and cardioprotection of propofol.</p><p><b>METHODS</b>The hearts of 30 Sprague-Dawley male rats were removed, mounted on a Langendorff apparatus, and randomly assigned to one of three groups (n = 10 each group) to be treated with the following treatments in a blinded manner: Group 1, control group, after perfusion with pure Krebs Henseleit bicarbonate (K-HBB) buffer solution for 15 minutes, hearts were subjected to 20 minutes global ischemia followed by 60 minutes reperfusion with pure K-HBB buffer; Group 2, after perfusion with K-HBB buffer solution containing propofol (10 microg/ml) for 15 minutes, the hearts underwent 20 minutes global ischemia followed by 60 minutes reperfusion with the same K-HBB buffer solution; Group 3, after perfusion with K-HBB buffer solution containing propofol (10 microg/ml) and L-NAME (100 micromol/L) for 15 minutes, the hearts underwent 20 minutes global ischemia followed by 60 minutes reperfusion with the same K-HBB buffer solution. The cardiac function was continuously monitored throughout the experiment. The coronary flow was also measured. An ISO-NO electrode was placed into the right atrium close to the coronary sinus to continuously measure NO concentration in the coronary effluent. The tissue samples from apex of hearts in Groups 1 and 2 were obtained to measure the NOS activity by spectrophotometry and the NOS contents by immunohistochemistry, respectively.</p><p><b>RESULTS</b>The cardiac function was significantly inhibited after ischemia and then gradually improved with reperfusion in all three groups. As compared with Group 1, the cardiac function variables and coronary flow at all the observed points were significantly improved in Group 2. The cardiac function variables and coronary flow were better in Group 3 than in Group 1, but were inferior in Group 3 than in Group 2. Both NO contents and NOS activity in the myocardium were significantly higher in Group 2 than in Group 1. However, NOS contents in the myocardium did not significantly differ between Groups 1 and 2.</p><p><b>CONCLUSIONS</b>In isolated rat hearts, propofol can improve cardiac functional recovery after ischemia-reperfusion by upregulating NOS activity in the myocardium. The NO system may play an important role in the preservation of myocardial ischemia-reperfusion injury produced by propofol.</p>

Comparison of bolus remifentanil versus bolus fentanyl for blunting cardiovascular intubation responses in children: a randomized, double-blind study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The authors found no study to compare the efficacy of bolus dose fentanyl and remifentanil blunting the cardiovascular intubation response in children, so they designed this randomized, double-blind clinical study to assess the effects of remifentanil 2 microg/kg and fentanyl 2 microg/kg by bolus injection on the cardiovascular intubation response in healthy children.</p><p><b>METHODS</b>One hundred and two children, the American Society of Anesthesiologists (ASA) physical status 1-2 and scheduled for elective plastic surgery under general anesthesia, were randomly divided into one of two groups to receive the following treatments in a double blind manner: remifentanil 2 microg/kg (Group R) and fentanyl 2 microg/kg (Group F) when anesthesia was induced with propofol and vecuronium. The orotracheal intubation was performed using a direct laryngoscope. Blood pressure (BP) and heart rate (HR) were recorded before anesthesia induction (baseline values), immediately before intubation, at intubation and every minute for 5 minutes after intubation. The percent changes of systolic blood pressure (SBP) and HR relative to baseline values and the rate pressure product (RPP) at every observing point were calculated. The incidences of SBP and HR percent changes >30% of baseline values and RPP >22,000 during the observation were recorded.</p><p><b>RESULTS</b>There were no significant differences between groups in the demographic data, baseline values of BP and HR and the intubation time. As compared to baseline values, BP, HR and RPP at intubation and their maximum values during observation increased significantly in Group F, but they all decreased significantly in Group R. BP, HR and RPP at all observed points, and their maximum values during the observation, were significantly different between groups. There were also significant differences between groups in the percent change of SBP and HR relative to baseline values at all observed points and their maximum percent changes during the observation. The incidences of SBP and HR percent increased >30% of the baseline values and RPP >22,000 during the observation, were significantly higher in Group F than in Group R, but the incidences of SBP and HR percent decreased >30% of baseline values were significantly lower in Group F compared with Group R.</p><p><b>CONCLUSIONS</b>When used as part of routine anesthesia induction with propofol and vecuronium in children, fentanyl 2 microg/kg by bolus injection fails to effectively depress the cardiovascular intubation response. Remifentanil 2 microg/kg by bolus injection can completely abolish the cardiovascular intubation response, but also cause more adverse complications of temporary significant cardiovascular depression.</p>

Clinical assessment of awake endotracheal intubation using the lightwand technique alone in patients with difficult airways / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There is few study to determine whether the use of the lightwand technique alone could achieve effective, safe and successful awake endotracheal intubation (ETI), therefore we designed a prospective clinical study to systematically evaluate the feasibility, safety and efficacy of awake ETI using the lightwand alone in patients with difficult airways.</p><p><b>METHODS</b>Seventy adult patients with difficult airways were enrolled in this study. After the desired sedation with fentanyl and midazolam, airway topical anesthesia was performed with 9 ml of 2% lidocaine, which were in order sprayed in three aliquots at 5 minutes intervals into the supraglottic (two doses) and laryngotracheal areas (one dose) using a combined unit of the lightwand and MADgic atomizer. After airway topical anesthesia, awake ETI was performed using a Lightwand. Subjective assessments by patients and operators using the visual analogue scores (VAS), and objective assessments by an independent investigator using patients' tolerance and reaction scores, coughing severity, intubating conditions and cardiovascular variables were taken as the observed parameters.</p><p><b>RESULTS</b>Of 210 airway sprays, 197 (93.8%) were successfully completed on the first attempt. The total time for airway spray was (14.6 +/- 1.5) minutes. During airway topical anesthesia, the average patients' tolerance scores were 1.7 - 2.3. After airway topical anesthesia, the mean VAS for discomfort levels that the patients reported was 6.5. Also airway topical anesthesia procedure was rated as acceptable and no discomfort by 94.3% of patients. The lightwand-guided awake ETI was successfully completed on first attempt within 29 seconds in all patients. During awake ETI, patients' reaction and coughing scores were 1.9 and 1.6, respectively. All patients exhibited excellent or acceptable intubating conditions. Cardiovascular monitoring revealed that changes of systolic blood pressure and heart rate at each stage of airway manipulations were less than 20% of baseline values. The postoperative follow-up showed that 95.7% of patients had no recall or slight memories of all airway instrumentation. The incidence of postoperative mild airway complications was 38.6%.</p><p><b>CONCLUSION</b>Alone use of the lightwand technique can achieve effective, safe and successful awake ETI in patients with difficult airways.</p>

Effect of remifentanil preconditioning on myocardial ischemia-reperfusion injury / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the delayed cardioprotection induced by remifentanil in intact rat ischemia-reperfusion (I/R) models.</p><p><b>METHODS</b>Totally 42 adult male Wistar rats weighing 200-300 g were randomly divided into 7 groups (n = 6 in each group): In Group I, rats were injected with normal saline via tail vein, performed with the regimen of 3 x 5-min intravenous (i.v.) infusion at a rate of 0.1 ml x kg(-1) min(-1) 24 h before I/R; In Group II, rats were treated according to the same experimental protocols as in Group I except receiving additional naloxone (0.1 mg/kg) 10 minutes before normal saline pretreatment; In Groups III, IV, V, and VI, rats were treated with remifentanil via tail vein, performed with the regime of 3 x 5-min i.v. infusion at a rate of 2 microg x kg(-1) x min(-1) 12 h, 24 h, 48 h, and 72 h before I/R; In Group VII, the rats were treated according to the same experimental protocols as in Group IV except that they received additional naloxone (0.1 mg/kg) 10 minutes before remifentanil pretreatment. Heart rate (HR), mean arterial pressure (MAP), and a lead II electrocardiogram were continuously monitored during IR process. To determine plasma concentration of creatine kinase myocardial isoenzyme-MB (CK-MB), arterial blood samples were obtained immediately before ischemia, and at the end of ischemia and reperfusion. After a 120-min reperfusion, heart was removed for the measurement of myocardial infarct size. Infarct size (IS) was expressed as percentage of the area at risk.</p><p><b>RESULTS</b>HR, MAP, and rate-pressure product were not significantly different at each time points among all groups (P > 0.05). Compared with Group I, plasma concentrations of CK-MB at the end of ischemia and reperfusion and myocardial infarct size were significantly lower in Groups IV and V (P < 0.05). Compared with Group IV, plasma concentrations of CK-MB at the end of ischemia and reperfusion were significantly higher and myocardial infarct size was significantly larger in Group VII (P < 0.05).</p><p><b>CONCLUSION</b>Remifentanil preconditioning induces delayed cardioprotection in intact rat ischemia-reperfusion model, which may be triggered via opioid receptors.</p>

Median effective dose of remifentanil for awake laryngoscopy and intubation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Awake intubation requires an anesthetic management that provides sufficient patient safety and comfort, adequate intubating conditions, and stable hemodynamics. In this prospective clinical study, our aim was to determine the median effective dose (ED(50)) of remifentanil in combination with midazolam and airway topical anesthesia for awake laryngoscopy and intubation.</p><p><b>METHODS</b>Thirty-six female adult patients, scheduled for elective plastic surgery under general anesthesia requiring orotracheal intubation were included in this study. Ten minutes after intravenous administration of midazolam 0.1 mg/kg, patients were assigned to receive remifentanil in bolus, followed by a continuous infusion. The bolus dose and infusion rate of remifentanil were adjusted by a modified Dixon's up-and-down method. Patient's reaction score at laryngoscopy and an Observer's Assessment of Alertness/Sedation Scale (OAA/S) were used to determine whether the remifentanil dosage regimen was accepted. During laryngoscopy, 2% lidocaine was sprayed into the airway to provide the topical anesthesia. ED(50) of remifentanil was calculated by the modified Dixon up-and-down method, and the probit analysis was then used to confirm the results obtained from the modified Dixon's up-and-down method. In the patients who were scored as "accept", patient's OAA/S and reaction scores at different observed points, intubating condition score and patient's tolerance to the endotracheal tube after intubation were evaluated and recorded. Blood pressure and heart rate at different measuring points were also noted.</p><p><b>RESULTS</b>ED(50) of remifentanil for awake laryngoscopy and intubation obtained by the modified Dixon's up-and-down method was (0.62 +/- 0.02) microg/kg. Using probit analysis, ED(50) and ED(95) of remifentanil were 0.63 microg/kg (95% CI, 0.54 - 0.70) and 0.83 microg/kg (95% CI, 0.73 - 2.59), respectively. Nineteen patients who were scored as "accept" had an OAA/S of > 15 and tolerated well laryngoscopy without significant discomfort or gagging. The mean intubating condition score was 1.8 +/- 0.8. The endotracheal tube was well tolerated. During awake laryngoscopy and intubation, blood pressure and heart rate were also kept stable. The postoperative follow up showed that no patient recalled discomfort and pain for airway manipulation.</p><p><b>CONCLUSIONS</b>When combined with midazolam 0.1 mg/kg and airway topical anesthesia, ED(50) of remifentanil for successful awake laryngoscopy and intubation is 0.62 microg/kg in bolus followed by continuous infusion of 0.062 microg*kg(-1)*min(-1). This sedation and analgesia regimen can provide patient safety and comfort, ensure adequate intubating conditions, maintain hemodynamic stability, and prevent negative recall of the airway procedure.</p>

Clinical experience of airway management and tracheal intubation under general anesthesia in patients with scar contracture of the neck / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Because patients with scar contracture of the neck are at a high risk of loss of the airway control after anesthesia induction, awake intubation is usually recommended. This retrospective clinical study was designed to evaluate the possibility, safety and efficacy of airway management and tracheal intubation under general anesthesia in such patients.</p><p><b>METHODS</b>This retrospective study included 1683 patients from January 1994 to December 2006 with scar contracture of the neck, aged 1.5 - 67.0 years, who were scheduled for elective plastic surgery under general anesthesia in Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Based on the results of the preoperative airway assessment, the patients were classified into group 1 (including 1375 patients with the atlanto-occipital extension of > 20 degrees and the Mallampatti's grade I or II) and group 2 (containing 308 patients with the atlanto-occipital extension of < 20 degrees and the Mallampatti's grade III or IV. In group 1, the intravenous induction and maintenance of anesthesia and succinylcholine for muscle relaxation were used. The intubation was done using a modified Macintosh technique. In group 2, the total intravenous anesthesia (TIVA) or the sevoflurane inhalation anesthesia was chosen and the spontaneous breathing was reserved during anesthesia. The intubation was performed by a fiberoptic stylet laryngoscope (FOSL). The number of intubation attempts, intubation time and relative complications were observed and recorded in all patients.</p><p><b>RESULTS</b>In group 1, the intubation was accomplished during the first attempt in 1279 cases (93%) and the intubation time was < 3 minutes in 1304 cases (95%). In group 2, the intubation was completed by the first attempt in 114 patients (37%) and 123 patients had an intubation time of < 3 minutes (40%). Tracheal intubation was successful by the second or third attempt in 96 patients in group 1 and 156 patients in group 2. Thirty-eight patients required four or more attempts which only occurred in group 2. The incidence of traumatic complication was 2.6% and 9.7% with one intubation attempt in groups 1 and 2, respectively, 12.5% and 17.0% with multiple intubation attempts (one vs multiple attempts in both groups, P < 0.001). All non-traumatic complications occurred in group 2 and laryngospasm and hypoxemia were more common in patients using the TIVA compared to those using the sevoflurane inhalational anesthesia (P < 0.001).</p><p><b>CONCLUSIONS</b>This study demonstrated that with a precise airway evaluation, an adequate preoperative preparation and a pre-planned failed intubation strategy, the anesthetist who was experienced in the difficult airway management could safely perform airway control and tracheal intubation under general anesthesia in patients with scar contracture of the neck. We believe that this technique may be very valuable for the management of a known difficult airway because it is comfortable for the patient and saves time for the anesthetist.</p>

Circulatory responses to nasotracheal intubation: comparison of GlideScope videolaryngoscope and Macintosh direct laryngoscope / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The GlideScope videolaryngoscope (GSVL) has been shown to have no special advantage over the Macintosh direct laryngoscope (MDL) in attenuating the circulatory responses to orotracheal intubation, but no study has compared the circulatory responses to nasotracheal intubation (NTI) using the two devices. This prospective randomized clinical study was designed to determine whether there was a clinically relevant difference between the circulatory responses to NTI with the GSVL and the MDL.</p><p><b>METHODS</b>Seventy-six adult patients were randomly allocated equally to the GSVL group and the MDL group. After induction of anesthesia, NTI was performed. Non-invasive blood pressure (BP) and heart rate (HR) were recorded before induction (baseline values) and immediately before intubation (post-induction values), at intubation and every minute for a further five minutes. During the observation, times required to reach the maximum values of systolic BP (SBP) and HR, times required for recovery of SBP and HR to postinduction values and incidence of SBP and HR percent changes > 30% of baseline values were also noted. The product of HR and systolic BP, i.e. rate pressure product (RPP), and the areas under SBP and HR vs. time curves (AUC(SBP) and AUC(HR)) were calculated.</p><p><b>RESULTS</b>The NTI with the GSVL resulted in significant increases in BP, HR and RPP compared to postinduction values, but these circulatory changes did not exceed baseline values. BPs at all measuring points, AUC(SBP), maximum values of BP and incidence of SBP percent increase > 30% of baseline value during the observation did not differ significantly between groups. However, HR and RPP at intubation and their maximum values, AUC(HR) and incidence of HR percent increase > 30% of baseline value were significantly higher in the MDL group than in the GSVL group. Times required for recovery of SBP and HR to postinduction values were significantly longer in the MDL group than in the GSVL group.</p><p><b>CONCLUSIONS</b>The pressor response to NTI with the GSVL and the MDL was similar, but the tachycardiac response to NTI was lesser and of a shorter duration when using a GSVL than when using an MDL.</p>

Comparison of hemodynamic responses to nasotracheal intubations with Glide Scope video-laryngoscope, Macintosh direct laryngoscope, and fiberoptic bronchoscope / 中国医学科学院学报

<p><b>OBJECTIVE</b>To compare the hemodynamic responses to nasotracheal intubation with Glide Scope video-laryngoscope (GSVL), Macintosh direct laryngoscope (MDLS), and fiberoptic bronchoscope (FOB).</p><p><b>METHODS</b>Sixty patients, with American Society of Anesthesiologists (ASA) physical status I - II, aged 18- 50 years, and scheduled for elective plastic surgery under general anesthesia requiring nasotracheal intubation, were randomly allocated equally to GSVL group, MDLS group, and FOB group. After the routine anesthesia induction, nasotracheal intubation was performed with the GSVL, MDLS, and FOB, respectively. Noninvasive blood pressure (BP) and heart rate (HR) were recorded before (baseline values) and after anesthesia induction (postinduction values), at intubation, and subsequently at an interval of every 1 minute for a total of five minutes. The maximum and minimum values of BP and HR during the observation period were also noted. The rate pressure product (RPP) at each measuring time point was calculated. The areas under effect-time curve (AUE) of hemodynamics were calculated by time as X-axis and changes of BP and HR during the observation as Y-axis.</p><p><b>RESULTS</b>All the three groups were similar in the demographic data and intubation time. After anesthesia induction, BP and RPP in all the three groups decreased significantly compared to baseline values (P < 0. 05), while HR had no significant change. After nasotracheal intubation, BP, HR, and RPP in all three groups were significantly higher than the postinduction values (P < 0.05). In the FOB group, BP, HR, and RPP at intubation significantly increased when compared with the baseline values (P < 0.05). In the MDLS group, HR at intubation, and maximum values of diastolic blood pressure (DBP), mean arterial pressure (MAP), HR, and RPP during the observation were significantly higher than the baseline values (P < 0.05). In the GSVL group, all hemodynamic parameters at intubation and after intubation were not significantly different from the baseline values. BP, HR, and RPP at intubation, and the incidences of HR more than 100 bpm during the observation were significantly higher in the FOB group than in the other two groups (P < 0.05). BP was not significantly different during the observation between the MDLS and GSVL groups, but HR and RPP at intubation and after intubation as well as AUE(HR) were significantly higher in the MDLS group than in the GSVL group (P < 0.05). AUE(HR) and AUE(SBP) were significantly lower in the GSVL group than in the FOB group (P < 0.05).</p><p><b>CONCLUSION</b>The hemodynamic responses to nasotracheal intubation are most severe with FOB, followed by MDLS, and then GSVL.</p>