RÉSUMÉ
Objective:To construct the quality evaluation system for tracheal extubation in the patients undergoing general anesthesia based on zero-defect management theory.Methods:Based on the model of zero-defect theory, literature review, semi-structured interviews, expert consultation and analytic hierarchy process were used to determine the content and weight of each index of the quality evaluation system for tracheal extubation in the patients undergoing general anesthesia.Results:The effective recovery rates of the two rounds of expert consultation questionnaires were 93% and 96% respectively; the expert authority coefficients were 0.946 and 0.947 respectively; the Kendall harmony coefficients were 0.247 and 0.250 respectively ( P<0.001). The final evaluation index system included 3 first-level indicators, 11 second-level indicators and 48 third-level indicators.The consistency coefficients of indicators at all levels were <0.1. Conclusions:The quality evaluation system for endotracheal extubation constructed for patients undergoing general anesthesia is highly scientific and reliable and can provide a basis for the quality evaluation of and continuous improvement in endotracheal extubation in the patients undergoing general anesthesia.
RÉSUMÉ
Objective To evaluate the accuracy of the middle finger length in predicting the depth of placement of oral endotracheal tube (ETT) in patients of different ages.Methods One hundred and twenty patients of both sexes,of American Society of Anesthesiologists physical status Ⅰ-Ⅲ,undergoing elective surgery under general anesthesia requiring insertion of ETT,were divided into adult (18-84 yr) group (n =98) and children (5-14 yr) group (n =22) according to age.After anesthesia induction,the length of trachea was measured through mouth with a fiberoptic bronchoscope,and the patients were endotracheally intubated with the depth of three times the length of the left middle finger.The length from ETT tip to carina was measured after positioning.The optimal depth of placement of ETT was calculated,and the rate of appropriate placement depth of ETT was calculated.Linear correlation of three times the length of the middle finger with the optimal placement depth of ETT was analyzed.Results The rate of appropriate placement depth of ETT was 88％,the excessively deep placement of ETT was 7％,and the excessively shallow placement of ETT was 5％ in adult group.The rate of appropriate placement depth of ETT was 90％,the excessively deep placement of ETT was 10％,and no excessively shallow placement of ETT was found in children group.The tip and cuff of ETT were all in the main trachea in the two groups.The optimal placement depth of ETT was positively correlated with three times the length of the left middle finger (r =0.774,P＜0.01) in adult group and (r=0.911,P＜0.01) in children group.Conclusion Three times the length of the left middle finger can predict the appropriate placement depth of oral ETT in patients of 18-84 yr and 5-14 yr.
RÉSUMÉ
Objective To investigate the effect of parecoxib sodium combined with dexmedetomi-dine on postoperative levels of plasma excitatory aminoacid and beta-amyloid protein(β-AP)in jugular bulb venous of elderly patients. Methods A total of 135 patients of either sex, aged 65-79 yr, weighing 47-76 kg, of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, undergoing elective open reduc-tion and internal fixation after tibial fracture and hip replacement, were divided into 3 groups(n=45 each) using a random number table: parecoxib sodium group(group P), dexmedetomidine group(group D)and parecoxib sodium combined with dexmedetomidine group(group PD). In group P, parecoxib sodium 40 mg (diluted to 5 ml in normal saline)was injected intravenously at 15 min before induction of anesthesia. In group D, dexmedetomidine was intravenously infused at a loading dose of 05 μg∕kg over 15 min starting from 15 min before induction of anesthesia, followed by an infusion of 05 μg·kg-1·h-1until the end of surgery. In group PD, parecoxib sodium 40 mg(diluted to 5 ml in normal saline)was intravenously injec-ted at 15 min before induction of anesthesia, and dexmedetomidine was intravenously infused at a loading dose of 05 μg∕kg over 15 min followed by an infusion of 05 μg·kg-1·h-1until the end of surgery at the same time. At 15 min before induction of anesthesia(T0), at the end of surgery(T1)and at 24, 48 and 72 h after surgery(T2-4), jugular bulb venous blood samples were taken for determination of concentrations of glutamate and aspartate in plasma(by reversed phase high-performance liquid chromatography)and β-AP(by enzyme-linked immunosorbent assay). Cognitive function was assessed at 1 day before surgery and 7 days after surgery using a battery of neuropsychologic tests including Wechsler Memory Scale, Digit Span (Forward and Backward), visual recognition and associative learning, Wechsler Adult Intelligence Scale and Trail Making Test Part A. The occurrence of postoperative cognitive dysfunction was recorded at 7 days after surgery. Results Compared with P and D groups, the concentrations of plasma glutamate at T2-3, plasma aspartate at T2and β-AP at T1and incidence of postoperative cognitive dysfunction were significantly decreased in group PD(P< 005). Conclusion The mechanism by which parecoxib sodium combined with dexmedetomidine decreases the occurrence of POCD may be related to inhibiting the levels of excitatory aminoacid and β-AP in brain tissues of elderly patients.
RÉSUMÉ
Objective To evaluate the effect of flurbiprofen axetil pretreatment on mesenteric trac-tion syndrome in elderly patients undergoing abdominal surgery. Methods Sixty patients of both sexes, aged 65-86 yr, with body mass index of 18.8-25.6 kg∕m2, of American Society of Anesthesiologists phys-ical status Ⅰor Ⅱ, scheduled for elective gastrointestinal tract surgery under general anesthesia, were di-vided into 2 groups(n=30 each)using a random number table: flurbiprofen axetil group(group F)and normal saline group(group NS). Flurbiprofen axetil 50 mg was intravenously injected during anesthesia in-duction in group F, while the equal volume of normal saline was given instead in group NS. Immediately af-ter anesthesia induction, immediately after mesenteric traction and at 10, 15 and 30 min after mesenteric traction, arterial blood samples were collected for measurement of plasma 6-keto-prostaglandin F1α concen-trations using enzyme-linked immunosorbent assay. The occurrence of mesenteric traction syndrome was re-corded within 30 min after mesenteric traction. Results Compared with group NS, the plasma 6-keto-pros-taglandin F1α concentrations were significantly decreased at each time point, and the incidence of mesen-teric traction syndrome was decreased during each period after mesenteric traction in group F(P<0.05). Conclusion Flurbiprofen axetil pretreatment can effectively prevent the development of mesenteric traction syndrome in elderly patients undergoing abdominal surgery.
RÉSUMÉ
Objective To investigate the effect of remote ischemic preconditioning (RIPC) combined with dexmedetomidine on lung injury during perioperative period and postoperative pulmonary complications in elderly patients with thoracotomy and pulmonary dysfunction.Methods Sixty ASA Ⅱ or Ⅲ patients aged 65-76 years [mean (70.4±6.3) years],weighing 50-75 kg,with moderate and severe pulmonary dysfunction,who were scheduled for elective radical operation for esophageal cancer,were randomly divided into 3 groups (n=20,each) by using a random number table:the control group (group C),RIPC group (group OR) and RIPC plus dexmedetomidine group (group ORD).At 10 min after endotracheal intubation,group ORD was induced by three cycles of 5 min of lower extremity ischemia followed by 5 min of reperfusion,at the same time a loading dose of dexmedetomidine 0.5 μig / kg was infused iv over 15 min,and then was infused at a rate of 0.5 μg · kg-1 · h-1 until the end of operation.Group OR was induced by three cycles of 5 min of lower extremity ischemia followed by 5min of reperfusion without dexmedetomidine.Group C received only the equal volume of normal saline.Blood samples were obtained from radial artery immediately before anesthesia induction (T0),before one lung ventilation (T1),at 1 h after one lung ventilation (T2),the end of surgery (T3) and 24 h after operation (T4).Blood gas analysis was done at T1,T2,and T3.Plasma superoxide dismutase (SOD) activity and concentration of malonyldialdehyde (MDA),matrix metallo-proteinase-9 (MMP-9),interleukin-6(IL-6) and white blood cell (WBC) and neutrophil granulocyte (PMN) counts were measured at T0,T2,T3 and T4.The complications including pulmonary infection and atelectasis were recorded at 1,3 and 7 days after operation.Results At T2-3,PaO2 was higher in groups of OR and ORD than in group C Group ORD had higher PaO2 than did group OR [(265±15) mmHg,(305±23) mmHg vs.(231±17) mmHg,(273±21)mmHg,(312±24) mmHg vs.(242±18) mmHg,F=34.791 and 31.813,P＜0.01].At T2-3,RI was lower in groups of OR and ORD than in group C,and group ORD had lower RI than did group OR [(1.48±0.16),(1.14 ±0.14) vs.(1.86±0.18);(1.35±0.13),(0.96±0.09) vs.(1.73±0.15),F=119.260 and 164.855,P＜0.01].At T3-4,SOD activity was higher in group OR and ORD than in group C,and group ORD had higher SOD activity than did group OR [(83.6 ± 7.8) U/mg prot,(97.6± 9.5) U/mgprot vs.(70.5±7.4) U/mgprot;(73.5 ± 6.3) U/mgprot,(87.7 ± 8.9) U/mgprot vs.(61.6 ± 5.4) U/ mgprot,F=94.540 and 90.839,P＜0.01].At T3-4.plasma concentration of MDA,MMP-9,WBC and PMN counts were lower in group OR and ORD than in group C,and the above indices were lower in group ORD than in group OR [(7.5 ± 1.4) nmol/mgprot,(5.8 ± 1.0) nmol/mgprot vs.(9.5 ±1.5) nmol/mgprot;(8.2± 1.5) nmol/mgprot,(6.5 ± 1.0) nmol/mgprot vs.(10.1 ±1.6) nmol/mgprot;(205±23) μg/L,(173±21) μg/L vs.(237±26) μg/L,(179±16) μg/L,(158±12) μg/L vs.(203± 20) μg/L;(8.0±0.5) ×109/L,(7.2±0.6) × 109/L vs.(9.2±0.8)×109/L;(9.4±0.7) ×109/L,(8.2±0.6)×109/Lvs.(11.2±0.8) ×109/L;(7.4±0.7) ×109/L,(6.5±0.5) ×109/Lvs.(8.3 ±0.8) ×109/L,(7.8±0.8) ×109/L,(6.7±0.6) ×109/L vs.(9.2±0.9) ×109/L,F=98.872,52.723;198.307,47.622,20.319,36.935,18.197,35.036,respectively,all P＜0.01].At T2-4,IL-6 level was lower in groups of OR and ORD than in group C,and group ORD had lower IL-6 level than did group OR [(105±14) ng/L,(86±12) ng/L vs.(127±18) ng/L;(125±19) ng/L,(101±16) ng/ L vs.(156±22) ng/L;(110±16) ng/L,(89±12) ng/L vs.(132±20) ng/L,F=85.449,139.848,124.129,respectively,P＜0.01].The incidences of postoperative pulmonary infection and atelectasis were lower in group OR and ORD than group C,and group ORD had lower incidences of postoperative pulmonary infection and atelectasis than did group OR (x2 =6.303 and 14.545,P ＜ 0.05).Conclusions RIPC combined with dexmedetomidine can improve pulmonary function in elderly patients with thoracotomy and pulmonary dysfunction,may relieve the inflammatory reaction and oxidation reaction during perioperative period and finally help to improve the prognosis of patients.
RÉSUMÉ
To evaluate the effect of dexmedetomidine on prognosis after cardiac surgery with cardiopulmonary bypass (CPB) in the patients.For this retrospective study,753 patients of both sexes,aged 18-84 yr,who underwent cardiac surgery with CPB from September 2013 to May 2015,were divided into 2 groups depending on whether or not dexmedetomidine was used during surgical procedures:control group (group C,n=548) and dexmedetomidine group (group D,n =205).Propensity score matching analysis with preset caliper width was used.A total of 197 matched pairs were selected from the patients.The development of postoperative arrhythmia,in-hospital mortality,pulmonary infection after operation,and acute renal injury,length of intensive care unit stay,length of hospital stay and 30-day readmission to the hospital were collected.Compared with group C,the incidence of postoperative tachyarrhythmia and inhospital mortality rate were significantly decreased (P＜0.05),and no significant changes were found in the incidence of postoperative bradyarrhythmia,pulmonary infection after operation and postoperative acute renal injury,length of intensive care unit stay,length of hospital stay and rate of 30-day readmission to the hospital in group D (P＞0.05).Dexmedetomidine can effectively improve prognosis after cardiac surgery with CPB in the patients.
RÉSUMÉ
Objective To investigate the effect of aloe polysaccharides (AP) pre-emptive treatment on the expression of nuclear factor kappa B (NF-κB),ntercellulor adhesion molecule-1 (ICAM-1) and cell apoptosis in hippocampal brain tissue in rats with severely hemorrhagic shock for the first time of entering high altitude.Methods Forty healthy male SD rats weighing 250-300 g were randomly (random number) divided into 5 groups (n =8 each):sham group,shock group and AP group which was further divided into 3 subgroups as per different dosages of AP administered (AP1:0.75 mg/kg; AP2:1.50 mg/kg; AP3:3.00 mg/kg).Rats in sham group were treated with surgical procedure without exsanguination.Rats in shock group were exsanguinated until hemorrhagic shock emerged without resuscitation.Rats in AP subgroups were intravenously infused with given doses of AP in different AP subgroups at 30 min before hemorrhagic shock.MAP was dropped to (35 ±5) mmHg (1 mmHg =0.133 kPa) in 15 min by bleeding from femoral artery,the mean arterial pressure (MAP) was maintained at (35 ±5) mmHg for 60 min with bleeding or re-transfusing.At 3 h after resuscitation,rats were sacrificed immediately by bleeding,and the hippocampus of brain was harvested on the ice.The expressions of NF-κB and ICAM-1 in the hippocampus of rats were determined by immuno-histochemical method,and number of cell apoptosis in the hippocampus of rats was determined by TUNEL.The means were compared with analysis of variance and Student-NewmanKeuls test,and statistical significance was established at a P value of less than 0.05.Results Compared with sham group,the expressions of NF-κB (5.03 ±0.42),ICAM-1 (4.14 ±0.29) and number of cell apoptosis (44.3 ± 7.2) in hippocampal tissue were significantly increased in shock group (P ＜ 0.05).There were no significant differences in these three variables between shock group and AP1 group.Compared with shock group,the expressions of NF-κB (3.12 ±0.34),ICAM-1 (2.93 ±0.21) and number of cell apoptosis (24.8 ± 3.6) in hippocampal tissue were significantly decreased in AP2 group (P ＜ 0.05).There were no significant differences in these three variables between AP2 and AP3 groups.Conclusion AP pre-emptive treatment can significantly attenuate the expressions of NF-κB,ICAM-1 and number of cell apoptosis in hippocampal tissue in hemorrhagic shock rats.
RÉSUMÉ
Objective To investigate the effects of downstream regulatory element antagonist modulator (DREAM) on the expression of glutamate transporter-1 (GLT-1) in spinal cord in rats with bone cancer pain and morphine tolerance.Methods Sixty female healthy Sprague-Dawley (SD) rats weighing 200 ～230 g were randomly divided into tow groups,group Ⅰ cancer pain (CP,n =48) and group Ⅱ Sham (S,n =12).Cancer pain in each group was produced by inoculation of syngenetic Walker 256 rat mammary gland carcinoma cells (5 × 105) to left tibia.Pain threshold to mechanical stimulus was measured before (baseline) and after the surgical procedure.From 14 d to 18 d after the inoculation of carcinoma cells,36 rats from group CP received subcutaneous injection of morphine at 3 times per day with doses increasingly from 10 mg/kg initially to 20 mg/kg,30 mg/kg,40 mg/kg,and 60 mg/kg.Equal volume of normal saline was applied to the 12 rats left in group CP.On 19th day after the carcinoma cells inoculation once subcutaneous injection of morphine at 3mg/kg was performed in all rats in group CP.From the next day,the rats in group CP ever receiving injections of morphine for 5 days were randomized into thre subgroups,including subgroups morphine tolerance (MT,n =12),vehicle (V,n =12),and RNAi (R,n =12).They were injected intrathecally with 20 μl of normal saline (NS),10 μl vehicle plus 10 μ1 NS,and 10 μ1 of DREAM-shRNA plus l0 μ1 NS,respectively,once a day for 5 days.Focusing on the affected limb,mechanical pain threshold was measured one day before surgery (T0),and at day7 (T1),day 14 (T2),day 18 (T3),day 19 (T4),day21 d (T5),day 25 (T6),and day 28 (T7) after surgery.The animals were sacrificed at day 28 after the procedure.The lumbar 4 segments in rats were removed for detection of DREAM and GLT-1.Results The mechanical threshold was significantly decreased at T1 compared to the baseline in all groups,returned to the baseline at T2 ～ T7 in group S,at T4 in group CP,and at T2 in group MT,V,and R,but remained low at T5 ～T7 in group CP,and at T3 ～T7 in group MT,V,and R.Compared to that at T1,it was decreased at T2 ～T3 and T5 ～ T7 in group CP,at T4 ～ T7 in group MT and V,and at T4 ～ T5 in group R,going back to the baseline at T4 in group CP and at T2 in group MT,V and R,and increased at T6 ～ T7 in group R.Compared to that in group S,the mechanical threshold in group CP,MT,V and R was decreased,and lower at T2 in group CP and at T4 in group MT,V and R.Compared to that in group CP,the mechanical threshold was significantly higher at T2 ～ T3 but lower at T4 in group MT,V,and R,decreased at T5 in group R and at T5 ～ T7 in group MT and V.The mechanical threshold was increased at T6 ～ T7 in group R and higher than that in groups MT and V.The expression of DREAM,compared to that in group S,was down-regulated in other groups.Compared to group CP,increment was shown in groups MT and V,and decrease was exhibited in group R.It was cut down in group R compared to that in groups MT and V.Compared to group S,GLT-1 was decreased in other groups.It was down-regulated in groups MT,V and R compared to group CP.Conclusions DREAM is involved in the development of allodynia after morphine tolerance in rats with bone cancer pain.No evidence in this study supports a link between DREAM and GLT-l in spinal cord.
RÉSUMÉ
Objective To investiga~ the effect of remote ischemic preconditioning (RIPC) combined with dexmedetomidine on the lung injury during one-lung ventilation (OLV) in the patients undergoing thoracic surgery.Methods Thirty ASA physical status Ⅰ or Ⅱ patients,aged 45-70 yr,weighing 51-69 kg,scheduled for elective radical operation for esophageal cancer,were randomly divided into 2 groups (n =15 each) using a random number table:control group (group C) and RIPC combined with dexmedetomidine group (group ORD).In ORD group,at 10 min after endotracheal intubation,RIPC was induced by 3 cycles of 5 min lower extremity ischemia followed by 5 min reperfusion,and at the same time a loading dose of dexmedetomidine 1.0 μg/kg was infused intravenously over 15 min and then dexmedetomidine was infused at a rate of 0.5 μg· kg-1 · h-1 until the end of operation.At 0,30 min,1 h and 2 h of OLV (T1-4),blood samples were obtained from the radial artery for blood gas analysis and determination of plasma concentrations of tumor necrosis factor-α (TNF-α),interleukin-1β (IL-1β) and IL-10.Oxygenation index and respiratory index were calculated.Exhaled breath condensate was collected at T1,T3 and T4,and the pH value was measured.Results Compared with group C,oxygenation index was significantly increased,and respiratory index was decreased at T2-4,the plasma concentrations of TNF-α and IL-1β were decreased,and the pH value of exhaled breath condensate was increased at T3-4,and the plasma concentration of IL-10 was increased at T4 in group ORD.Conclusion RIPC combined with dexmedetomidine can inhibit inflammatory responses and reduce airway acidification,thus attenuating the lung injury during OLV in the patients undergoing thoracic surgery.
RÉSUMÉ
Objective To investigate the effects of selective lobar ventilation on intrapulmonary shunt and inflammatory response in patients with pulmonary dysfunction during thoracotomy.Methods Thirty-four ASA Ⅱ or Ⅲ patients,aged 64-79 years,weighing 50-85 kg,with moderate or severe impaired pulmonary function,scheduled for esophageal cancer radical correction,were randomly divided into two groups (n =17 each):one-lung ventilation group (group A) and selective lobar ventilation group (group B).In group A,an endobronchial blocker tube was used to obstruct the bronchus principalis and practice one-lung ventilation.In group B,an endobronchial blocker tube was used to obstruct the bronchi Iobares and practice selective lobar ventilation.Blood samples were taken from the arteria radialis and the internal jugular vein for blood gas analysis and determination of plasma concentrations of tumor necrosis factor-alpha (TNF-α),interleukin-6 (IL-6) and IL-8 by enzyme linked immunosorbent assay (ELISA) before anesthesia induction (T0),30 minutes following two-lung ventilation at the lateral position (T1),60 minutes following one-lung ventilation or selective lobar ventilation (T2) and at the end of surgery (T3).Peak airway pressure (Ppeak) and plateau airway pressure (Pplat) were recorded at the same time.Results The incidence of hypoxemia was significantly lower in group B (0) than in group A (18％,P ＜ 0.05).Compared with group A,Pliat and Ppeak at T1-3,the intrapulmonary shunt rate (Qs/Qt) at T2,TNF-α,IL-6 and IL-8 concentrations at T2-3 were significantly decreased in group B (P ＜ 0.05).Conclusion Selective lobar ventilation can reduce intrapulmonary shunt and inhibit inflammatory responses to help lessen mechanical ventilation-related lung injuryduring thoracotomy in patients with pulmonary dysfunction.
RÉSUMÉ
Objective To investigate the efficacy of ventilation with selective lobar collapse for thoracic surgery in elderly patients with chronic obstructive pulmonary disease (COPD).Methods Thirty ASA Ⅱ or Ⅲ patients with COPD,aged 65-80 yr,with a body mass index of 16-28 kg/m2,undergoing radical resection of esophagus cancer,were randomly divided into 2 groups (n=15 each):one-lung ventilation (OLV) group and ventilation with selective lobar collapse group (group SLC).In group OLV,OLV was performed,while in group SLC,the balloon of the blocker was placed at 0.5 cm below the opening of the upper lobe bronchus and the lower lobe was collapsed when chest was open.The patients were mechanically ventilated (VT =7-8 ml/kg,RR =14-16 bpm,I∶E=1∶1.5-2.0,FiO2 =100％).Peak pressure (Ppeak),plateau pressure (Pplat),airway resistance (Raw),and dynamic lung compliance (Cd) were measured at 10 min of two-lung ventilation in supine position (T0),at 5,45 and 90 min of OLV or selective lobar collapse (T1-3) and at 10 min of two-lung ventilation in lateral position after the end of operation (T4).Arterial blood samples were obtained at To,T3 and T4 for blood gas analysis.Oxygenation index (OI),alveolar-arterial oxygen gradiant (P(A-a)O2),and respiratory index (RI) were calculated.Results Ppeak,Pplat and Raw were significantly lower at T2-4,while Cd was significantly greater at T1-4,OI was significantly higher at T3,4,and P(A-a)O2 and RI were significantly lower at T3,4 in group SLC than in group OLV.Conclusion The thoracic operation can be completed safely using ventilation with selective lobar collapse and OLV,however,ventilation with selective lobar collapse can improve oxygenation and provides better ventilatory efficacy than OLV in elderly patients with COPD.
RÉSUMÉ
ObjectiveTo investigate the effects of selective lobar ventilation on intrapulmonary shunt and inflammatory response in patients with pulmonary dysfunction during thoracotomy.MethodsThirty-four ASA Ⅱ or Ⅲ patients,aged 64-79 yr,weighing 50-85 kg,with moderate and severe impaired pulmonary function,scheduled for esophageal cancer radical correction,were randomly divided into 2 groups( n =17 each): one-lung ventilation group (group A) and selective lobar ventilation group (group B).In group A,endobronchial blocker tube was used to obstruct bronchus principalis and practice one-lung ventilation.In group B,endobronchial blocker tube was used to obstruct bronchi lobares and practice selective lobar ventilation.The blood samples were taken from arteria radialis and internal jugular vein for blood gas analysis and determination of the plasma concentrations of TNF-α,IL-6 and IL-8 by ELISA before anesthesia induction(T0 ),at 30 min following two-lung ventilation at lateral position (T1),at 60 min following one-lung ventilation or selective lobar ventilation (T2) and at the end of surgery (T3).Ppeak and Plat.were recordeded at the same time.ResultsThe incidence of hypoxemia was significantly lower in group B (0) than in group A(18％ )( P ＜0.05).Compared with group A,Pplat and Ppeak at T1-3,Qs/Qt at T2,TNF-α,IL-6 and IL-8 concentrations at T2-3 were significantly decreased in group B( P ＜ 0.05 ).Conclusion The selective lobar ventilation can reduce intrapulmonary shunt,inhibit inflammatory response to help lessen mechanical ventilation related lung injury during thoracotomy in patients with pulmonary function.
RÉSUMÉ
Objective To investigate the effect of positive airway pressure on catheterization of right internal jugular vein (IJV) in anesthetized patients. Methods One hundred and twenty-five ASA Ⅰ or Ⅱ patients aged 19-64 yr weighing 44-85 kg undergoing right IJV catheterization were randomly divided into 2 groups: control group (group C, n = 60) and positive airway pressure group (group P, n = 65). Anesthesia was induced with midazolam, sufentanil and etomidate. Tracheal intubation was facilitated with vecuronium. The patients were mechanically ventilated. Right IJV was catheterized under the guidance of ultrasound and was punctured at the plane of cricoid cartilage. IJV catheterization was performed when mechanical ventilation was suspended in group C and when airway pressure was maintained at 20 cm H2O in group P. The cross section area of right IJV, CVP, the shortest dislance between right IJV and the skin and the depth of needle insertion were measured. The number of attempts to puncture the vein was calculated and the easiness of withdrawing blood from the right IJV after being pierced was assessed. MAP and HR were measured before and after positive airway pressure. Results Positive airway pressure (20 cm H2O) significantly increased the cross section area of IJV, CVP, success rates of puncturing IJV at first attempt and within 30 seconds and easiness of withdrawing blood from IJV after being pierced and deceased the depth of needle insertion as compared with control group. Positive airway pressure (20 cm H2O) also significantly increased the incidence of bradycardia and hypotension. Conclusion Positive airway pressure is helpful for right IJV catheterization guided by ultrasound under general anesthesia.