Comparison of head-down lithotomy position and Trendelenburg position on cardiac output in patients undergoing gynecological laparoscopic surgery / 复旦学报（医学版）

Objective To compare the changes in cardiac output (CO) and other hemodynamic parameters in patients undergoing gynecological laparoscopic surgery in head-down lithotomy position and Trendelenburg position. Methods Sixty patients were divided into head-down lithotomy group and Trendelenburg group. CO was recorded as baseline by a noninvasive cardiac output monitor NICOM? system after the placement of patients. These measurements were also acquired when the patients were placed in the 30° head-down tilt(T0)following pneumoperitoneum establishment.Stroke volume(SV), heart rate(HR)and CO were monitored at 1-minute intervals thereafter for a total of 10 minutes(T1-T10),and mean arterial pressure(MAP)and total peripheral resistance(TPR)were monitored every 5 minutes. Results The reduction of CO in head-down lithotomy group was greater than that in Trendelenburg group(T0:-31％±19％ vs.-9％±34％;T1:-32％±18％ vs.-16％±38％;T2:-33％± 19％vs.-16％±26％;T3:-32％±22％vs.-16％±28％;T4:-31％±18％vs.-12％±38％;T5:-30％± 17％vs.-14％±37％;T6:-31％±17％ vs.-14％±33％,all P<0.05)during the first 6 minutes. MAP at baseline in head-down lithotomy group was significantly higher than that in Trendelenburg group[(97±11) mmHg vs.(85±6)mmHg,P<0.05].MAP decreased in head-down lithotomy group at T0(-8％±16％) and increased in Trendelenburg group at T5 and T10(T5:9％±15％,T10:12％±18％). Conclusion CO reduction was greater in patients in head-down lithotomy position than that in Trendelenburg position group during the first 10 minutes after adjusting the position following pneumoperitoneum establishment.

Positioning of a morbidly obese patient during retinal surgery

A body mass index (BMI) ?35 kg/m2 is classified as obese, and a BMI ?40 kg/m2 is classified as morbidly obese. Obese people are at a higher risk for developing cardiovascular complications like ischemic heart diseases, congestive cardiac failure, hypertension, type 2 diabetes mellitus and obstructive sleep apnea (OSA) among other health issues. Central obesity can also increase the pleural pressure and cardiac filling pressures, thus increasing the intracranial (ICP) and intraocular pressure (IOP). These clinical co-morbidities can make retina surgeries, which require patient in supine position for 45-90 minutes, a challenging task. We present our experience in the intraoperative positioning of such a patient who underwent surgery for retinal detachment.

Effects of transcutaneous electrical acupoint stimulation on recovery of patients undergoing robotic gynecologic surgery / 临床麻醉学杂志

Objective To observe whether transcutaneous electrical acupoint stimulation (TEAS) could improve the emergence and recovery of patients undergoing robotic gynecologic surgery,and to explore the mechanism behind it.Methods Patients (aged 18-65 years,BMI 18-30 kg/m2,ASA grade Ⅰ or Ⅱ) scheduled for elective robotic gynecologic surgery were screened and randomized into three groups:group TEAS (groups T),no acupoint group (group N) and control group (group C),receiving TEAS (ST-36,SP6,BL59,BL60),stimulation at bilateral hips and no-stimulation respectively.Stimulations were given from 30 min before anesthesia induction to the end of surgery.Recovery measurements during emergence,PACU stay and 24 h after surgery were recorded.Levels of serum AQP4,MMP9 and S100β were analyzed.Results Time to response to verbal command and time to extubation in group T [(18.3± 6.7) min and (19.4 ± 6.6) min respectively] were significantly shorter than those in group C [(21.9±7.3) min and (23.1±7.3) min respectively] (P ＜0.05).Maximum VAS scores during PACU stay were significantly lower in group T than that in groups C and N (P＜0.05).Postoperative AQP4 level in group T significantly decreased compared with baseline (P＜0.05).However,postoperative MMP9 and S100β level in group C significantly in creased compared with the baseline (P＜0.05 or P＜0.01).Conclusion TEAS could fasten emergence of patients after robotic gynecologic surgery and improve postoperative analgesia.Mechanisms involving AQP4,MMP9 and S100β may be involved.

Influence of the positive endexpiratory pressure and Trendelenburg position on the right jugular vein in obese patients / 中国医师进修杂志

Objective The internal jugular vein puncture catheter had some difficulties and challenges for obese patients.Whether positive end expiratory pressure and Trendelenburg position will increase the cross-sectional area of the right internal jugular vein in obese patients. Methods Forty patients were selected for perioperative period.Male-to-female ratio was 19:21;age ranged from 43 to 69 years. ASA wasⅠ-Ⅲ, and BMI was ≥ 30 kg/m2. After induction of general anesethesia and end intubation,the patients were placed in a supine position on a level bed with the head turning to the left 20°.The transverse diameter, anter-posterior diameter and the cross-sectional area of the right internal jugular vein were measured incrementally from the lowest to the highest with PEEP 0,5 and 10 cmH2O (1 cmH2O=0.098 kPa) and the head-down position angle of 20°. Ultrasound was used to measure and record the transverse diameter, anter-posterior diameter and the cross-sectional area of the right internal jugular vein at the level of the cricoid cartilage. Results All PEEP levels increased the transverse diameter, anter-posterior diameter and the cross-sectional area of the right internal jugular vein compared with the control: (1.38 ± 0.34) cm2vs. (0.73 ± 0.30), (0.97 ± 0.26) and (1.15 ± 0.30) cm2;(1.50 ± 0.30)cm vs.(1.00 ± 0.26),(1.18 ± 0.27)and(1.29 ± 0.26)cm;(1.01 ± 0.16)cm vs.(0.57 ± 0.16), (0.75 ± 0.18)and(0.84 ± 0.16)cm,P<0.05.Six patients were excluded because the blood pressure was below 90/60 mmHg (1 mmHg=0.133 kPa) after PEEP 10 mmHg was seted. Transverse diameter, anter-posterior diameter and the cross-sectional area of the right internal jugular vein was larger at the head-down position angle 20°compared with that at the PEEP levels.The largest cross-sectional area was (1.38 ± 0.34)cm2.Conclusions The use of positive end expiratory pressure and Trendelenburg position increases transverse diameter, anter-posterior diameter and the cross-sectional area of the right internal jugular vein in obese patients.Transverse diameter, anter-posterior diameter and the cross-sectional area of the right internal jugular vein is the largest at the head-down position angle 20°, then the PEEP 10 cmH2O.Airway pressure is the largest at the head-down position angle 20°.When we set the PEEP 10 cmH2O, some patients′ blood pressure is below 90/60 mmHg. AS for the airway pressure and hemodynamic instability, we recommend using PEEP 5 cmH2O to facilitate internal jugular venous cannulation in obese patients.

Effect of Trendelenburg position and artificial pneumoperitoneum on change of respiratory mechanics in-dexes due to change of preset airway pressure in PCV / 实用医学杂志

Objective In pressure controlled ventilation(PCV),a self-control method was used to ob-serve the change of respiration mechanics indexes under Trendelenburg position and pneumoperitoneum versus su-pine position and non-pneumoperitoneum with preset airway pressure.Methods Thirty patients scheduled for lapa-roscopic radical resection of rectal carcinoma were enrolled in this study.ECG,MAP,SpO2,BIS and body temper-ature were routinely detected. After induction of anesthesia,volume controlled ventilation(VCV)was used as ba-sic ventilation,and then switched to PCV after 5 minutes. The airway pressure was the preset airway pressure be-fore pneumoperitoneum,then was lowered 1 cmH2O in proper order,and then restored preset airway pressure and increased 1 cmH2O. 15 minutes after pneumoperitoneum,the airway pressure of PCV was used as preset airway pressure after pneumoperitoneum,and then the above procedure was repeated.The time interval was at least 5 min-utes.The values of MAP,HR,SpO2,VT and Cdyn were recorded at each time;VT,and Cdyn were continuously recorded five times to take the average value. The postoperative recovery in patients was observed. Results After pneumoperitoneum,the values of Cdyn and VT were significantly reduced(P < 0.01),MAP was increased(P <0.05). When the preset airway pressure changed 1 cmH2O,ΔVT was decreased(P < 0.05),and the change of Cdyn was not statistically significant. Conclusions As altering a unit of the preset airway pressure in PCV,the change in VT is significantly reduced but Cdyn does not change markedly in Trendelenburg posture and artificial pneumoperitoneum,as compared with supine position and non-pneumoperitoneum.

Effect of CO2 pneumoperitoneum combined with position changes on stability of cardiac electrophysiology in gynecological laparoscopy / 实用医学杂志

Objective To observe the effect of CO2 pneumoperitoneum combined with position changes on the stability of cardiac electrophysiology in gynecological laparoscopy. Methods The gynecological laparoscopy was performed for 30 patients to undergo elective gynecological laparoscopy under general anesthesia ,with the pneumoperitoneum pressure of 12 mmHg and the Trendelenburg positionat 15° . The observations and analyses were done over the basic monitoring index and the QT interval (QT),T peak tend interval (Tp-e),heart rate corrected QT interval(QTc),QT dispersion(QTd),Tp-e/QT before anesthesia(T0),after anesthesia(T1),1 min after pneumoperitoneum (T2),30 min after pneumoperitoneum and head-down tilt (T3),30 min after deflation and supine position(T4). Results Compared with the time point of T0,QTd increased significantly at T1(P<0.05) and so it was with QT,QTc,QTd,Tp-e,Tp-e/QT at T2,T3,and T4(P<0.05). Compared with the time point of T2,QTc,QTd,Tp-e,Tp-e/QT significantly increased at T3(P < 0.05). Conclusions CO2 pneumoperitoneum combined with Trendelenburg position can prolong ventricular repolarization duration and destroy the stability of cardiac electrophysiology so it may increase the incidence of cardiovascular events.

Neu-P11 reduces IOP through inhibiting oxidative stress level of acute high IOP rats / 中国药理学通报

Aim To explore the effect of Neu-P11,a novel melatonin agonist with similar function of melatonin,on IOP of acute high IOP animals and the related mechanism.Methods The experiment used the Trendelenburg position(head low feet high position of 80°)to establish acute high IOP model.Rats were placed in the Trendelenburg position and used Tonopen XL contact tonometer to measure IOP(every 5 minutes measured once IOP,and the maximum value in 20 minutes)in 8 :00～9 :00 am.And then,thirty Sprague-Dawley rats(8 week-old)were divided into five groups: normal IOP+normal saline,high IOP+normal saline,high IOP+10 mg·kg-1 Mel,high IOP+20 mg·kg-1 Neu-P11,high IOP+50 mg·kg-1 Neu-P11.Put in a flat to rest 2 h,animals were placed in Trendelenburg position again and then,IOP was measured every hour in the flat by 6 hours.After excessive sodium pentobarbital administration continuous for 1 week,the serum was collected and stored for subsequent detection at the end of the experiment.The level of MDA,SOD and GSH-Px enzyme activity of the rat serum was tested by kit accordingly.HE staining method was used to identify the SD rat retinal morphological changes.Results Trendelenburg position could induce IOP of model group rats,which was increased by 202.9％(P<0.01)and the content of MDA,reduced the activity of SOD and GSH-Px enzyme,retinal thickening was observed and its level was not clear.Neu-P11/Mel could significantly improve oxidative stress level and retinal edema in rats.Conclusion Neu-P11 could reduce IOP of the acute high IOP animals,which might be involved in the lower level of oxidative stress in the body.

Effect of the 20° trendelenburg position on hypotension during induction of general anesthesia of patients undergoing gastrectomy / 临床麻醉学杂志

Objective To explore the effect of 20°trendelenburg position on hemodynamics during induction of general anesthesia of patients under gastrectomy.Methods One hundred and eighteen patients (77 males and 41 females,aged 50-60 years,ASA physical status Ⅰ or Ⅱ),scheduled for elective radical gastrectomy,were randomly divided into group A (n=40),group B (n=38) and group C (n=40).In group A,patients were placed in the supine position during induction of anesthesia,and vasopressors was administered when hypotension occurred.In group B,patients were placed in the supine position during induction of anesthesia and was placed in the 20°trendelenburg position when hypotension occurred,and vasopressor would be administered if blood pressure was not restored.In group C,patients were placed in the 20°trendelenburg position during induction of anesthesia,and vasopressors was administered when hypotension occurred.In all groups Lactated Ringer′s was infused at 15 ml·kg-1·h-1in 30 min before induction.Anesthesia was induced with propofol 2 mg/kg,sufentanil 0.5 μg/kg,rocuronium 0.9 mg/kg.The occurrence of hypotension and the total amounts of drug administrations were doccumented.Results Nineteen patients (47.5%) in group A,fourteen patients (36.8%) in group B and six patients (15.0%) in group C developed hypotention.The incidence of hypotension in group A and B was significantly higher than that in group C (P<0.05).In all groups the total dosage of ephedrine was used.Phenylephine was only used in the group A at a dose of 26.5±0.14 μg.The amounts of drug administrations in group B and C were significantly lower than that in group A (P<0.05).Two patients in group A went into a refractory hypotensive state.However,no patients in all groups fell into a serious arrhythmia state,so atropine was not used.Conclusion The 20°trendelenburg position during induction of general anesthesia of patients during gastrectomy can prevent hypotension during induction.This position is effective in the management of hypotension after the induction of general anesthesia and can decrease the amounts of drug administrations during induction of general anesthesia.

Application of BIS and muscle relaxation monitors in robot-assisted laparoscopic radical prostatectomy / 临床麻醉学杂志

Objective To evaluate the effect of bispectral index (BIS) and muscle relaxation monitoring on robot-assisted laparoscopic radical prostatectomy in elderly patients.Methods One hundred elderly patients (aged 65-80 years,ASA Ⅰ or Ⅱ) who underwent robot-assisted laparoscopic radical prostatectomy were randomly allocated into BIS and muscle relaxation monitoring group (group AA,n=50) and control group (group AC,n=50).In group AA,propofol was infused to achieve the BIS value of 45-55,and we monitored the muscle relaxation to conduct closed-loop infusion of cisatracurium.In group AC,we regulated the depth of anesthetic with the patients` vital signs according to anesthetists` experience.Mean arterial pressures (MAP),heart rates (HR),airway platform pressure (Pplat),and airway peak pressure (Ppeak) were recorded at following time points: before anesthesia induction (T0),after anesthesia induction (T1),10 min (T2),60 min (T3) after artificial pneumoperitoneum,and the end of operation (T4).We recorded dosage of propofol,cisatracurium,sufentanil,remifentanil,vasoactive agent,extubation time and PACU stay time.Results At T1,T2 and T4,the MAP and HR in group AC were significantly higher than those in group AA (P<0.05);at T3,MAP in group AC were apparently lower than those in group AA (P<0.05).Compared with T0,MAP and HR in group AC were significantly increased at T1,T2 and T4(P<0.05),MAP in group AC were obviously reduced at T3 (P<0.05),MAP and HR in group AC were also fluctuated obviously at different time points.MAP and HR in group AA at each point had no statistically significant difference.Compared with T1,Pplat and Ppeak in the two groups were significantly increased at T2-T4 (P<0.05).Pplat and Ppeak in grpup AC were higher than those in group AA at T2,T3 (P<0.05).Compared with group AC,the dosages of propofol and cisatracurium were less in group AA.The postoperative extubation time and PACU stay time were shorter in group AA.Conclusion BIS and muscle relaxation monitoring in robot-assisted laparoscopic radical prostatectomy can effectively stablize hemodynamics,reduce airway pressure fluctuation and the dosage of anesthetics.It also shortens the extubation time and the PACU stay time and improves the anesthesia recovery quality.

Hemisphere cerebral infarction after total laparoscopic hysterectomy in the Trendelenburg position: A case report

Perioperative stroke can lead to mortality or serious disability and usually occurs in patients undergoing cardiac, vascular, or neurologic surgery; it is rare in gynecological surgery. We report the case of a patient who suffered life-threatening cerebral infarction after elective laparoscopic hysterectomy. During the surgery, the patient was placed in the Trendelenburg position. On postoperative day one, the patient was diagnosed with right hemisphere cerebral infarction; brain computed tomographic angiography showed proximal right internal carotid artery occlusion. Decompressive craniectomy was performed to resolve brain swelling, but the patient died 10 days later.

Application of self-made one-piece shoulder pillow in patients undergoing gynecological laparoscopy with lithotomy position and trendelenburg position / 现代临床护理

Objective To explore the effect of one-piece shoulder pillow on patients suffering from shoulder pain and skin erubescence during gynecological laparoscopy with lithotomy position and trendelenburg position. Methods Two hundred and six patients who underwent gynecological laparoscopic operation were divided into control and experiment groups according to cardinal or even number of registration. The patients in both groups were set in lithotomy position and trendelenburg position during the operation, with the difference in the use of a common shoulder pillow for support in the control group but no use in the experiment one. On-position time and incidence rate of shoulder pain and skin erubescence were compared between two groups. Result The sholder pain and skin erubescence were less than those of control group (P < 0.05). Conclusion Use of one-piece shoulder pillow can reduce the incidence rates of shoulder pain and skin erubescence after gynecological laparoscopic operation with lithotomy position and trendelenburg position.

Effect of recruitment maneuver on arterial oxygenation in patients undergoing robot-assisted laparoscopic prostatectomy with intraoperative 15 cmH₂O positive end expiratory pressure / 대한마취과학회지

BACKGROUND: This randomized, controlled study was designed to compare the effects of recruitment maneuvers (RMs) with a 15 cmH₂O positive end-expiratory pressure (PEEP) on the systemic oxygenation and lung compliance of patients with healthy lungs following robot-assisted laparoscopic prostatectomy (RALP). METHODS: Sixty patients undergoing a RALP with an intraoperative 15 cmH₂O PEEP were randomly allocated to an RM or a Control group. The patients in the RM group received a single RM through the application of a continuous positive airway pressure of 40 cmH₂O for 40 s 15 min after being placed in the Trendelenburg position. The arterial oxygen tension (PaO₂, primary endpoint) and the pulmonary dynamic and static compliances (secondary endpoints) were measured 10 min after the anesthetic induction (T1), 10 min after establishment of the pneumoperitoneum (T2), 10 min after establishment of the Trendelenburg position (T3), 10 min after the RM (T4), 60 min after the RM (T5), and 10 min after deflation of the pneumoperitoneum in the supine position (T6). RESULTS: The intergroup comparisons of the PaO₂ showed significantly higher values in the RM group than in the Control group at T4 and T5 (193 ± 35 mmHg vs. 219 ± 33 mmHg, P = 0.015, 188 ± 41 mmHg vs. 214 ± 42 mmHg, P = 0.005, respectively). However, the PaO₂ at T6 was similar in the two groups (211 ± 39 mmHg vs. 224 ± 41 mmHg, P = 0.442). Moreover, there were no statistical differences between the groups in the dynamic and static compliances of the lungs at any time point. CONCLUSIONS: The arterial oxygenation of the patients with a healthy lung function who had undergone a RALP with intraoperative 15 cmH₂O PEEP was improved by a single RM. However, this benefit did not last long, and it did not lead to an amelioration of the lung mechanics.

Effects of Systemic Administration of Dexmedetomidine on Intraocular Pressure and Ocular Perfusion Pressure during Laparoscopic Surgery in a Steep Trendelenburg Position: Prospective, Randomized, Double-Blinded Study

Increased intraocular pressure (IOP) during surgery is a risk factor for postoperative ophthalmological complications. We assessed the efficacy of systemically infused dexmedetomidine in preventing the increase in IOP caused by a steep Trendelenburg position, and evaluated the influence of underlying hypertension on IOP during surgery. Sixty patients undergoing laparoscopic surgery in a steep Trendelenburg position were included. Patients in the dexmedetomidine group received a 1.0 µg/kg IV loading dose of dexmedetomidine before anesthesia, followed by an infusion of 0.5 µg/kg/hr throughout the operation. Patients in the saline group were infused with the same volume of normal saline. IOP and ocular perfusion pressure (OPP) were measured 16 times pre- and intraoperatively. In the saline group, IOP increased in the steep Trendelenburg position, and was 11.3 mmHg higher at the end of the time at the position compared with the baseline value (before anesthetic induction). This increase in IOP was attenuated in the dexmedetomidine group, for which IOP was only 4.2 mmHg higher (P < 0.001 vs. the saline group). The steep Trendelenburg position was associated with a decrease in OPP; the degree of decrease was comparable for both groups. In intragroup comparisons between patients with underlying hypertension and normotensive patients, the values of IOP at every time point were comparable. Dexmedetomidine infusion attenuated the increase in IOP during laparoscopic surgery in a steep Trendelenburg position, without further decreasing the OPP. Systemic hypertension did not seem to be associated with any additional increase in IOP during surgery. (Registration at the Clinical Research Information Service of Korea National Institute of Health ID: KCT0001482)

Comparison of volume-controlled and pressure-controlled ventilation in the Trendelenburg position for gynecological laparoscopic surgery

BACKGROUND: Minimal invasive gynecologic surgery usually requires pneumoperitoneum and Trendelenburg positioning, which results in adverse effects on respiratory and hemodynamic parameters. The aim of this study was to investigate the effects of volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) introduced sequentially in patients who underwent gynecological laparoscopy on respiratory mechanics, cardiovascular responses, and gas exchange. METHODS: Forty patients who were scheduled for gynecologic laparoscopic surgery were enrolled. Baseline ventilation of their lungs was performed with VCV with a tidal volume (TV) of 8 ml/kg ideal body weight (IBW). Forty minutes after pneumoperitoneum and Trendelenburg positioning, the ventilation mode was changed to PCV, and airway pressure was set to provide a TV of 8 ml/kg IBW without exceeding 35 cmH2O. Respiratory mechanics and hemodynamic and gas exchange parameters were recorded at 10 minutes after induction, 30 minutes after CO2 pneumoperitoneum and Trendelenburg positioning, 30 minutes after PCV, and 30 minutes after desufflation and supine position. RESULTS: After pneumoperitoneum and Trendelenburg positioning, there were significant increases in systolic blood pressure, diastolic blood pressure, central venous pressure, peak airway pressure (PAP), mean airway pressure (Pmean), whereas lung compliance and PaO2 significantly decreased. The decrease in PAP and increases of Pmean, lung compliance and PaO2 were observed during PCV compared with VCV (P < 0.05). There were no differences in hemodynamic parameters between VCV and PCV. CONCLUSIONS: Our results demonstrated that PCV may be an effective method of ventilation during gynecologic laparoscopy in terms of improved oxygenation and minimizing adverse respiratory mechanics.

Position does not affect the optic nerve sheath diameter during laparoscopy / 대한마취과학회지

BACKGROUND: Increase in intracranial pressure (ICP) is one of the physiologic changes during laparoscopic surgery, which is known to be associated with positional changes. Changes of ICP can be measured directly by invasive method, but ultrasonographic measurement of optic nerve sheath diameter (ONSD) is known to be a rapidly applicable technique for evaluating ICP. The aim of this study is to investigate the change of ONSD according to the positional change during laparoscopic surgery. METHODS: Female patients scheduled to undergo laparoscopic surgery were enrolled. Fifty-seven patients were assigned according to the position during surgery (Group T: gynecological surgery, Trendelenburg position, n = 27 vs. Group RT: laparoscopic cholecystectomy, Reverse trendelenburg position, n = 30). After induction of anesthesia, ONSD, PaCO2, end-tidal carbon dioxide (ETCO2), and mean arterial pressure (MAP) were measured. Parameters were measured at 6 time points during surgery. RESULTS: There were no significant differences in the demographic data of patients, procedure time, and anesthesia. After pneumoperitoneum and positional change, ONSD, ETCO2, and MAP increased in both groups until 15 min and returned to the baseline. However, no significant differences in changes of ONSD, PaCO2, ETCO2, and MAP were observed between two groups. CONCLUSIONS: ONSD during laparoscopic surgery with pneumoperitoneum increased slightly until 15 minutes, but there were no significant differences according to the position. Increases in ICP during laparoscopic surgery with short period of pneumoperitoneum would be small in disregard of position in patients without intracranial pathology.

Reverse trendelenburg position can alleviate postoperative nausea and vomiting in thyroid surgery: from Logistic multivariate analysis / 中华内分泌外科杂志

Objective To assess the clinical significance of reverse trendelenburg position in preventing postoperative nausea and vomiting(PONV)in thyroid surgery.Methods 110 patients with papillary thyroid carcinoma(PTC) admitted from Feb.2013 to Mar.2014 were prospectively divided into experimental group and the control group according to whether reserve trendelenburg position was adopted.Univariate and multivariate method were used to analyze relations between PONV and surgical position,gender,age,body mass index,hypertension,surgical time,ASA classification,anesthesia,and motion sickness.Results Of the 110 cases of PTC,the incidence of PONV was 16.28％ (7/43) in the experimental group while it was 37.31％ (25/67) in the control group.The difference had statistical significance(P ＜ 0.05).Statistical analysis showed that PONV was related to patients'gender,surgical position,surgical time,and motion sickness,while only surgical position and motion sickness was the independent risk factors.Conclusion Reverse trendelenburg position surgery can help to prevent PONV and promote recovery.

Effect of Trendelenburg position on right and left internal jugular vein cross-sectional area / 대한마취과학회지

BACKGROUND: Unlike the right internal jugular vein (RIJV), there is a paucity of data regarding the effect of the Trendelenburg position on the left internal jugular vein (LIJV). The purpose of this study is to investigate the cross-sectional area (CSA) of the LIJV and RIJV and their response to the Trendelenburg position using two-dimensional ultrasound in adult subjects. METHODS: This study enrolled fifty-eight patients with American Society of Anesthesiologists physical status class I-II who were undergoing general anesthesia. CSAs of both the RIJV and LIJV were measured with a two-dimensional ultrasound in the supine position and then in a 10degrees Trendelenburg position. RESULTS: In the supine position, the transverse diameter, anteroposterior diameter, and CSA of the RIJV were significantly larger than those of the LIJV (P < 0.001). Of 58 patients, the RIJV CSA was larger than the LIJV CSA in 43 patients (74.1%), and the LIJV CSA was larger than the RIJV CSA in 15 patients (25.9%). In the Trendelenburg position, CSAs of the RIJV and LIJV increased 39.4 and 25.5%, respectively, compared with the supine position. However, RIJV changed at a rate that was significantly greater than that of the LIJV (P < 0.05). Of 58 patients, the RIJV CSA was larger than the LIJV CSA in 48 patients (82.8%), and the LIJV CSA was larger than the RIJV CSA in 10 patients (17.2%). CONCLUSIONS: In supine position, the RIJV CSA was larger than the LIJV CSA. The increased CSA in the Trendelenburg position was greater in the RIJV than the LIJV.

Postural Intraocular Pressure Change at Trendelenberg Position Measured by Rebound Tonometer

PURPOSE: This study was carried out to evaluate the postural intraocular pressure (IOP) change in Trendelenburg, reverse Trendelenburg, and supine positions in healthy young males. METHODS: We measured the IOP values of 5 healthy young male volunteers (10 eyes) using an Icare PRO rebound tonometer in sitting, Trendelenburg, reverse Trendelenburg, and supine positions. RESULTS: The mean IOP in the supine position (18.63 mm Hg) was significantly higher (p < 0.01) than in the sitting position (15.31 mm Hg). When maintaining the Trendelenburg position, IOP gradually increased. CONCLUSIONS: In our study, the Trendelenburg position significantly increased the IOP compared to that in the supine position. The effects of increased IOP should be considered in situations that require Trendelenburg positioning, such as exercise or surgery.

The correlation between the Trendelenburg position and the stroke volume variation / 대한마취과학회지

BACKGROUND: The stroke volume variation (SVV), based on lung-heart interaction during mechanical ventilation, is a useful dynamic parameter for fluid responsiveness. However, it is affected by many factors. The aim of this study was to evaluate the effects of SVV on Trendelenburg (T) and reverse Trendelenburg (RT) position and to further elaborate on the patterns of the SVV with position. METHODS: Forty-two patients undergoing elective surgery were enrolled in this study. Fifteen minutes after standardized induction of anesthesia with propofol, fentanyl, and rocuronium with volume controlled ventilation (tidal volume of 8 ml/kg of ideal body weight, inspiration : expiration ratio of 1 : 2, and respiratory rate of 10-13 breaths/min), the patients underwent posture changes as follows: supine, T position at slopes of operating table of -5degrees, -10degrees, and -15degrees, and RT position at slopes of operating table of 5degrees, 10degrees, and 15degrees. At each point, SVV, cardiac output (CO), peak airway pressure (PAP), mean blood pressure, and heart rate (HR) were recorded. RESULTS: The SVV was significant decreased with decreased slopes of operating table in T position, and increased with increased slopes of operating table in RT position (P = 0.000). Schematically, it was increased by 1% when the slope of operating table was increased by 5degrees. But, the CO and PAP were significant increased with decreased slopes of operating table in T position, and decreased with increased slopes of operating table in RT position (P = 0.045, 0.027). CONCLUSIONS: SVV is subjected to the posture, and we should take these findings into account on reading SVV for fluid therapy.

The simultaneous application of positive-end expiratory pressure with the Trendelenburg position minimizes respiratory fluctuations in internal jugular vein size / 대한마취과학회지

BACKGROUND: The respiratory cycle alters the size of the right internal jugular vein (RIJV). We assessed the changes in RIJV size during the respiratory cycle in patients under positive pressure ventilation. Moreover, we examined the effects of positive-end expiratory pressure (PEEP) and the Trendelenburg position on respiratory fluctuations. METHODS: A prospective study of 24 patients undergoing general endotracheal anesthesia was performed. Images of the RIJV were obtained in the supine position with no PEEP (baseline, S0) and after applying three different maneuvers in random order: (1) a PEEP of 10 cmH2O (S10), (2) a 10degrees Trendelenburg tilt position (T0), and (3) a 10degrees Trendelenburg tilt position combined with a PEEP of 10 cmH2O (T10). Using the images when the area was smallest and largest, cross-sectional area (CSA), anteroposterior diameter, and transverse diameter were measured. RESULTS: All maneuvers minimized the fluctuation in RIJV size (all P = 0.0004). During the respiratory cycle, the smallest CSA compared to the largest CSA at S0, S10, T0, and T10 decreased by 28.3 8.5, 8.0, and 4.4%, respectively. Furthermore, compared to S0, a 10degrees Trendelenburg tilt position with a PEEP of 10 cmH2O significantly increased the CSA in the largest areas by 83.8% and in the smallest areas by 169.4%. CONCLUSIONS: A 10degrees Trendelenburg tilt position combined with a PEEP of 10 cmH2O not only increases the size of the RIJV but also reduces fluctuation by the respiratory cycle.