The effect of a continuous infusion of low-dose esmolol on the requirement for remifentanil during laparoscopic gynecologic surgery

Study ObjectiveTo investigate whether a continuous infusion of low-dose esmolol results in an opioid-sparing effect during surgery.DesignRandomized, double-blinded, placebo-controlled clinical comparison study.SettingOperating room of a university hospital.Patients56 ASA physical status 1 and 2 patients, aged 20 to 60 years, undergoing laparoscopic gynecologic surgery of less than two hours’ duration.InterventionsThe esmolol group (n = 28) received a 0.5 mg/kg loading dose of esmolol followed by an infusion of esmolol 30 μg/kg/min; the saline group (n = 28) received equivalent volumes of normal saline.MeasurementsThe effect-site concentration of remifentanil (ng/mL) to maintain adequate anesthetic depth before infusion of the study drug (before-concentration) was measured. During infusion of study drug, the effect-site concentration of remifentanil was adjusted every 5 minutes to maintain systolic blood pressure within 15% of baseline and a Bispectral Index value between 50–60. The average of these adjusted concentrations (after-concentration) was measured and compared to the before-concentration. The quality of postoperative recovery was assessed.Main ResultsIn the esmolol group, the after-concentration of remifentanil was decreased by 33.3% compared with the before-concentration. The total dose of remifentanil infused was also lower in the esmolol group (0.09 ± 0.1 vs 0.14 ± 0.03 μg/kg/min; P = 0.031). The esmolol group had lower scores on a pain numerical rating scale and required less fentanyl in the Postanesthesia Care Unit.ConclusionsIntraoperative esmolol infusion decreases both the requirement for remifentanil and postoperative administration of rescue analgesics.     

Target-controlled infusion of remifentanil or fentanyl during extra-corporeal shock-wave lithotripsy

BACKGROUND AND OBJECTIVE: Target-controlled infusions (TCIs) of remifentanil and fentanyl in conscious sedation regimes for extra-corporeal shock-wave lithotripsy have not been reported. We estimated the effect site concentrations of remifentanil and fentanyl needed to obtain adequate analgesia in 50% of patients (EC50) and compared both drugs in terms of intra- and post-procedure complications. METHODS: Forty-four adult patients were randomly distributed into two groups: Group R received remifentanil and Group F received fentanyl TCI with initial effect site concentrations of 1.5 and 2 ng mL(-1), respectively. Pain was assessed using a 10-point verbal analogue scale and <3 was considered adequate analgesia. Increments or decrements of 0.5 ng mL(-1) were then introduced for subsequent patients according to Dixon's up and down method. During the rest of the procedure, TCI was adjusted to maintain verbal analogue scale <3. RESULTS: Remifentanil and fentanyl EC50 were 2.8 ng mL(-1) (95% confidence interval (CI): 1.8-3.7 ng mL(-1)) and 2.9 ng mL(-1) (95% CI: 1.7-4.1 ng mL(-1)), respectively (n.s.). At EC50, the probability of having a respiratory rate <10 was 4% (95% CI: 0-57%) for remifentanil and 56% (95% CI: 13-92%) for fentanyl. Hypoxaemia, vomiting and sedation were more frequent in Group F during and after the procedure (P < 0.05). CONCLUSIONS: A similar EC50 but more respiratory depression, sedation and PONV were found with fentanyl TCI than with remifentanil TCI.     

A retrospective analysis of a remifentanil/propofol general anesthetic for craniotomy before awake functional brain mapping

We performed this study to summarize drug dosing, physiologic responses, and anesthetic complications from an IV general anesthetic technique for patients undergoing craniotomy for awake functional brain mapping. Review of 98 procedures revealed "most rapid" IV infusion rates for remifentanil 0.05, 0.05-0.09 microg x kg(-1) x min(-1) and propofol 115, 100-150 microg x kg(-1) x min(-1). The infusions lasted for 78, 58-98 min. Intraoperative emergence from general anesthesia was 9 (6-13) min after discontinuing IV infusions to allow for brain mapping and was independent of infusion duration and duration of craniotomy before mapping. Spontaneous ventilation was generally satisfactory during drug infusion, as evidenced by Sao(2) = 95% (92%-98%) and Paco(2) = 50 (47-55) mm Hg. However, we recorded at least one 30-s epoch of apnea in 69 of 96 patients. Maximum systolic arterial blood pressure was 150 (139-175) mm Hg and minimal systolic arterial blood pressure was 100 (70-150) mm Hg during drug infusion. Three patients experienced intraoperative seizures. Two patients did not tolerate the awake state and required reinduction of general anesthesia. No patients required endotracheal intubation or discontinuation of surgery. This general anesthetic technique is effective for craniotomy with awake functional brain mapping and offers an alternative to continuous wakefulness or other IV sedation techniques. IMPLICATIONS: An IV general anesthetic technique using remifentanil and propofol is an effective method allowing for reliable emergence for intraoperative awake functional brain mapping during craniotomy.     

靶控输注瑞芬太尼抑制气管拔管期呛咳反应的临床研究

目的测定瑞芬太尼抑制50%及95%患者拔管期呛咳反应的效应室浓度(EC₅₀及EC₉₅),为其应用于全身麻醉苏醒期拔管管理提供可靠依据和合适的药物浓度。方法 23例ASAⅠ或Ⅱ级全身麻醉下行颈前路减压植骨内固定术男性患者,用Dixons序贯法和Probit分析确定瑞芬太尼抑制呛咳反应的EC₅₀、EC₉₅及其各自的95%可信区间（95%CI）。结果根据Probit分析计算瑞芬太尼抑制患者拔管期呛咳反应的EC₅₀为1.67ng/ml（95%CI为1.44～1.96ng/ml）,EC₉₅为2.13ng/ml（95%CI为1.89～3.34ng/ml）。结论全麻拔管期抑制患者呛咳反应的瑞芬太尼EC₉₅为2.13ng/ml,维持此浓度靶控输注（TCI）可安全、有效地消除呛咳,改善全麻苏醒质量。     

Intestinal obstruction in appendicitis: A retrospective cohort study

Background

Appendicitis as a cause of intestinal obstruction is an infrequent condition. The purpose of this study was to define the incidence and frequency of intestinal obstruction, according to the classification of intestinal obstruction secondary to appendicitis, and to characterise their severity.

Methods

A retrospective cohort study analysing all patients operated on for intestinal obstruction secondary to appendicitis within a 15-year period was designed. Continuous and categorical variables including age, gender, time interval between onset of symptoms and diagnosis, C-reactive protein and white blood cells values, type of intestinal obstruction and WSES Sepsis Severity Score, were included.

Results

During the period of study 3626 patients were operated on for appendicitis and 44 cases had associated intestinal obstruction (1.2%). According to the classification of intestinal obstruction in appendicitis, most patients had a mechanical ileus with strangulation (48%) and a WSES Sepsis Severity Score of 3 or less points (77%).

Conclusions

The incidence of intestinal obstruction in appendicitis was higher than expected. These patients have a severe inflammatory response with a WSES Sepsis Severity Score of 3 points. According to the classification of intestinal obstruction in appendicitis, most patients had a mechanical obstruction with strangulation.

     

靶控输注与静脉输注瑞芬太尼复合异丙酚用于局部麻醉患者镇静镇痛术效应的比较

目的 比较靶控输注与静脉输注瑞芬太尼复合异丙酚用于局部麻醉患者镇静镇痛术的效应.方法 局部麻醉辅助镇静镇痛术下择期整形外科手术的患者60例,年龄18 ～ 55岁,体重指数＜ 30 kg/m2,ASA分级Ⅰ或Ⅱ级,采用随机数字表法,将患者随机分为2组(n=30):静脉输注组(V组)和靶控输注组(T组).T组局部麻醉前靶控输注瑞芬太尼(初始靶浓度1.0 ng/ml)和异丙酚(初始靶浓度1.0 μg/ml),V组瑞芬太尼静脉负荷剂量0.25 μg/kg,维持速率0.05μg-kg-1·min-1,异丙酚负荷剂量0.5 mg/kg,维持速率3mg· kg-1·h-1.术中调整靶浓度或输注速度以维持改良的OAA/S评分2或3分,术中记录低氧血症、呼吸过缓和/或暂停的发生情况,计算异丙酚和瑞芬太尼的总用量.结果 与V组比较,T组术中低氧血症、呼吸过缓和/或暂停的发生率明显降低,异丙酚和瑞芬太尼总用量明显减少(P＜0.05).结论 靶控输注瑞芬太尼复合异丙酚用于局部麻醉患者镇痛镇静术具有良好的安全性目效应优于静脉输注.     

Comparison of predicted and real propofol and remifentanil concentrations in plasma and brain tissue during target-controlled infusion: a prospective observational study

Target-controlled infusion systems are increasingly used to administer intravenous anaesthetic drugs to achieve a user-specified plasma or effect-site target concentration. While several studies have investigated the ability of the underlying pharmacokinetic-dynamic models to predict plasma concentrations, there are no data on their performance in predicting drug concentrations in the human brain. We assessed the predictive performance of the Marsh propofol model and Minto remifentanil model for plasma and brain tissue concentrations. Plasma samples were obtained during neurosurgery from 38 patients, and brain tissue samples from nine patients. Propofol and remifentanil concentrations were measured using gas chromatography mass spectrometry and liquid chromatography tandem mass spectrometry. Data were analysed from the nine patients in whom both plasma and brain samples were simultaneously obtained. For the Minto model (five patients), the median performance error was 72% for plasma and −14% for brain tissue concentration predictions. The model tended to underestimate plasma remifentanil concentrations, and to overestimate brain tissue remifentanil concentrations. For the Marsh model (five patients), the median prediction errors for plasma and brain tissue concentrations were 12% and 81%, respectively. However, when the data from all blood propofol assays (36 patients) were analysed, the median prediction error was 11%, with overprediction in 15 (42%) patients and underprediction in 21 (58%). These findings confirm earlier reports demonstrating inaccuracy for commonly used pharmacokinetic-dynamic models for plasma concentrations and extend these findings to the prediction of effect-site concentrations.     

Evaluation of analgesic efficacy and opioid sparing effect of pregabalin after arthroscopic rotator cuff repair surgery: A retrospective cohort study

BackgroundConsidering the adverse effects of opioids, it is essential to minimize their consumption for postoperative pain control. Studies have reported the opioid sparing effects of pregabalin, with conflicting results. Evidence for administering pregabalin in a multimodal regimen after arthroscopic rotator cuff repair surgery is limited.MethodsA total of 64 patients who underwent arthroscopic rotator cuff repair were enrolled in the cohort, and their data were retrospectively analyzed to evaluate the ability of pregabalin for postoperative analgesia and opioid sparing. The pregabalin group (n = 32) received additional pregabalin 75 mg for 2 weeks from the day before the surgery with the standard pain medications; in contrast, the control group (n = 32) was prescribed the standard pain medications alone. The total volume of patient-controlled anesthesia, doses of oral oxycodone and intravenous morphine as rescue analgesics, number of adverse events, and patient satisfaction based on the numeric rating scale (0–10) were assessed. Further, we used the visual analog scale for evaluating pain and function for 6 months in each group.ResultsTotal patient-controlled anesthesia volume, number of patient-controlled anesthesia attempts on the day of surgery, and total oral oxycodone consumption were significantly lower in the pregabalin group. Visual analog scale scores for pain and function showed no significant differences. Although the total number of adverse effects (nausea, vomiting, dizziness, dry mouth, urinary retention, itching sense, or constipation) was higher in the pregabalin group than in the control group, the difference was not statistically significant.ConclusionOur multimodal regimen with pregabalin significantly reduced opioid consumption with similar adverse effects. However, there was no significant difference in the pain score. We recommend pregabalin as an additional analgesic for arthroscopic rotator cuff repairs, especially for medium to large sized tears.     

Long-term renal function in living kidney donors with simple renal cysts: A retrospective cohort study

Simple (Bosniak I) renal cysts are considered acceptable in living kidney donor selection in terms of cancer risk. However, they tend to increase in number and size over time and might compromise renal function in donors. To clarify their implications for long-term renal function, we characterized the prevalence of renal cysts in 454 individuals who donated at our center from 2000 to 2007. We estimated the association between the presence of cysts in the kidney remaining after nephrectomy (ie, retained cysts) and postdonation eGFR trajectory using mixed-effects linear regression. Donors with retained cysts (N = 86) were older (P < .001) and had slightly lower predonation eGFR (median 94 vs 98 mL/min/1.73 m², P < .01) than those without cysts. Over a median 7.8 years, donors with retained cysts had lower baseline eGFR (_−8.7 −5.6 _−2.3 mL/min/1.73 m², P < .01) but similar yearly change in eGFR (_−0.4 0.02 _0.4 mL/min/1.73 m², P = .2) compared to those without retained cysts. Adjusting for predonation characteristics, there was no difference in baseline eGFR (P = .6) or yearly change in eGFR (P > .9). There continued to be no evidence of an association when we considered retained cyst(s) ≥10 mm or multiple retained cysts (all P > .05). These findings reaffirm current practices of accepting candidates with simple renal cysts for donor nephrectomy.     

Effects of prostacyclin infusion on renal function during cardiopulmonary bypass

Infusion of prostacyclin inhibits platelet activation during cardiopulmonary bypass (CPB) but also results in systemic arterial hypotension. Therefore, the effects of CPB and prostacyclin on renal function were studied in 36 male patients undergoing aortocoronary bypass. Nineteen patients (Group 1) received prostacyclin, 50 ng per kilogram of body weight per minute, during CPB, and 17 patients (Group 2) served as controls. There was pronounced hypotension in Group 1 only. Urine production during CPB averaged 88 +/- 140 ml and 2,306 +/- 1,112 ml in Groups 1 and 2, respectively. No patient had renal failure. Glomerular filtration rate (GFR), as measured by clearance of chromium 51-labeled ethylenediaminetetraacetic acid, was increased in Group 1 from 86 +/- 14 to 99 +/- 22 ml/1.73 m2/min (p less than 0.05) the day after operation, but remained unchanged in Group 2 (81 +/- 15 to 82 +/- 21 ml/1.73 m2/min). The increased GFR in Group 1 can be regarded as an expected adaptation to the change in body fluids after CPB. Therefore, the unchanged GFR in Group 2 must be regarded as caused by insufficient adaptation or impaired renal function. Proximal tubular function was evaluated by determination of beta 2-microglobulin in urine. In both groups, urinary beta 2-microglobulin and the ratio of urinary beta 2-microglobulin to urinary creatinine were increased the day after operation. The hypotension in Group 1 did not exacerbate the damage to tubular function.     

Organ donor management and delayed graft function in kidney transplant recipients: A multicenter retrospective cohort study

Meeting donor management goals (DMGs) has been reported to decrease the incidence of delayed graft function (DGF) after kidney transplant, but whether this relationship is independent of cold machine perfusion is unclear. We aimed to determine whether meeting DMGs is associated with a reduced incidence of DGF, independent of the use of machine perfusion. We collected data on consecutive brain‐dead donors and their KT recipients (KTRs) between June 2013 and December 2016 in 5 adult transplant centers. We evaluated whether DMGs were met at donor neurologic death (DND) and later time points. We defined a priori meeting optimal DMG as achieving ≥7 DMGs. Generalized estimating equations were used to predict DGF. Among 122 donors, 34% were extended‐criteria donors (ECDs). The number of DMGs met increased over time (5.6 ± 1.4 at DND and 6.1 ± 1.3 at organ procurement [P < .001]). DGF occurred in 23% of 214 KTRs, and 55% received organs placed on machine perfusion. In multivariate analysis, ECD (odds ratio [OR] 2.24, 95% confidence interval [CI] 1.13‐4.45), use of machine perfusion (OR 0.45, 95% CI 0.22‐0.94), and optimal DMG at DND (OR 0.39, 95% CI 0.16‐0.99) were associated with DGF. Early achievement of DMGs was associated with a reduced risk of the development of DGF, independent of the use of machine perfusion.     

Hematological profile and transfusion requirement during hysteroscopic myomectomy: A comparative study between oxytocin and tranexamic acid infusion

BackgroundOxytocin is uterotonic drug reducing uterine blood loss. Tranexamic acid reduce blood loss in various settings. Data on their efficacy are limited in gynecological hysteroscopy. This study was conducted to compare the effect of oxytocin versus tranexamic acid on hematological profile and transfusion requirement during hysteroscopic myomectomy (HM).MethodsFifty women scheduled for HM were randomly assigned into two groups. Ttranexamic acid (TXA) or oxytocin (OXY). TXA was injected with 15 mg kg^?1 of tranexamic acid, followed by infusion of 10 mg kg^?1 h^?1. In OXY, 10 Unites of oxytocin were added to 500 mL saline (400 mU/min) during surgery. Spinal anesthesia was induced for all patients. Hemodynamics, hematological data, number of transfusions, serum sodium and central venous pressure were measured.ResultsTXA showed significant decrease of heart rate 30 and 45 min and 1 and 2 h when compared with OXY. Post operative Hb and Hct showed significant decrease (p < 0.001) in TXA compared with OXY. CVP in TXA displayed significant increase (p < 0.001) 15 min after spinal blockade and 30 min, 45 min, 1 h and 2 h. Serum sodium showed significant decrease in TXA (p < 0.001) compared with OXY nearly throughout study period.ConclusionUse of oxytocin during HM was accompanied with stable hemodynamics, hematological profile and less transfusion requirement compared with the use of tranexamic acid.     

静脉输注瑞芬太尼诱发大鼠心肌氧化应激水平的效应

目的 评价静脉输注瑞芬太尼诱发大鼠心肌氧化应激水平的效应.方法 健康雄性SD大鼠180只,体重250 ～ 300 g,5～6月龄,采用随机数字表法,将其随机分为15组(n=12):对照组(C组)、缺血预处理组(IPC组)、瑞芬太尼预处理组(RPC组)及静脉输注瑞芬太尼组,静脉输注瑞芬太尼组速率分别为1、5、10、20 μg·kg-1·min-1,输注时间分为15、60、120 min,分别为R1-15组、R1-60组、R1-120组、R5-15组、R5-60组、R5-120组、R10-15组、R10-60组、R10-120组、R20-15组、R20-120组和R20-120组.在动脉圆锥与左心耳之间左冠状动脉前降支下穿线,15 min后进行分组处理.采用结扎左冠状动脉前降支进行心肌缺血,IPC组心肌缺血5 min,再灌注5 min,共3个循环;RPC组静脉输注瑞芬太尼5μg·kg-1·min-15 min,暂停5 min,共3个循环.每组取6只大鼠,于分组处理30 min时进行心肌缺血30 min,再灌注120 min时取心肌组织,测定心肌梗死面积.每组取另外6只大鼠,于分组处理结束后取心肌组织,测定氧自由基、丙二醛和硝基酪氨酸的水平.结果 与C组比较,IPC组、RPC组、R1-120组、R5-60组、R5-120组和R10-60组心肌梗死面积缩小,R1-120组、R5-60组、R5-120组、R10-60组、R10-120组、R20-15组、R20-60组和R20-120组心肌组织氧自由基表达上调,R20-15组、R20-60组和R20-120组心肌组织丙二醛和硝基酪氨酸的含量升高(P＜0.05或0.01).结论 高速率和长时间输注瑞芬太尼可诱发大鼠心肌氧化应激反应.