早期目标导向型镇静用于ICU机械通气患者的效果评价

目的评价早期目标导向型镇静(EGDS)策略在ICU机械通气患者的应用效果。方法将2015年1~10月收治ICU符合纳入及排除标准的76例机械通气患者按随机数字法分为干预组和对照组,干预组42例采用EGDS策略;对照组34例采用标准化镇静策略。比较两组48h内浅镇静达标率、谵妄发生率及ICU住院日。结果干预组48h内浅镇静达标率显著高于对照组(P0.01),谵妄发生率及ICU住院日显著低于/短于对照组(均P0.05)。结论 EGDS策略相对安全、可行,较标准化镇静策略能更有效使ICU机械通气患者达到早期浅镇静目标。     

Dexmedetomidine versus propofol for prolonged sedation in critically ill trauma and surgical patients

Backgroundand Purpose: Currently, dexmedetomidine versus propofol has primarily been studied in medical and cardiac surgery patients with outcomes indicating safe and effective sedation. The purpose of this study was to assess the efficacy of dexmedetomidine versus propofol for prolonged sedation in trauma and surgical patients.MethodsThis was a single-center prospective study conducted in the Trauma/Surgical Intensive Care Unit (ICU) at a Level I academic trauma center. It included patients 18 years of age or older requiring mechanical ventilation who were randomly assigned based on unit bed location to receive either dexmedetomidine or propofol. The primary outcome was duration of mechanical ventilation. Secondary outcomes included mortality; proportion of time in target sedation; incidence of delirium, hypotension, and bradycardia; and ICU and hospital length of stay (LOS).ResultsA total of 57 patients were included. Baseline characteristics were similar between groups. There was no significant difference in duration of mechanical ventilation (median [IQR]) between the dexmedetomidine (78.5[125] hours) and propofol (105[130] hours; p = 0.15) groups. There was no difference between groups in ICU mortality, ICU and hospital LOS, or incidence of delirium. Safety outcomes were also similar. Patients in the dexmedetomidine group spent a significantly greater percentage of time in target sedation (98[8] %) compared to propofol group (92[10] %; p = 0.02).ConclusionsOur results suggest that, similar to medical and cardiac surgery patients, dexmedetomidine and propofol are safe and effective sedation agents in critically ill trauma and surgical patients; however, dexmedetomidine achieves target sedation better than propofol for this specific population.     

Spinal anaesthesia with ropivacaine 5 mg ml(-1) in glucose 10 mg ml(-1) or 50 mg ml(-1)

Forty patients undergoing spinal anaesthesia for a variety ofsurgical procedures were randomly allocated to receive 3 mlof ropivacaine 5 mg ml^–1 in glucose 10 mg ml^–1 or50 mg ml^–1. Onset of sensory block to T10 was significantlyfaster (P=0.03) with the glucose 50 mg ml^–1 solution (median5 min, range 2–20 min) than with the 10 mg ml^–1solution (median 10 min, range 2–25 min). Maximum extentof cephalad spread was virtually the same in both groups (10mg ml^–1 median T6/7, range T3–T10; 50 mg ml^–1median T6, range T3–T10) with similar times to regressionbeyond S2 (10 mg ml^–1 median 210 min, range 150–330min; 50 mg ml^–1 median 210 min, range 150–330 min).Complete motor block was produced in the majority of patients(10 mg ml^–1 90%; 50 mg ml^–1 85%) and the time tocomplete regression was the same in both groups (median 120min, range 90–210 min). A block adequate for the projectedsurgery was achieved in all patients. Br J Anaesth 2001; 86: 241–4     

Bispectral index correlates well with Richmond agitation sedation scale in mechanically ventilated critically ill patients

Purpose  

The clinical sedation scores available for assessing sedation in the intensive care unit (ICU) have drawbacks and limit their usefulness in paralyzed and deeply sedated patients. An objective tool, the bispectral index (BIS), could prove beneficial in such circumstances. We evaluated the ability of BIS to assess the level of sedation and its correlation with the Richmond agitation sedation scale (RASS) in ICU.     

右美托咪定和咪达唑仑用于机械通气患者镇静效果的比较

目的 比较右美托咪定和咪达唑仑用于机械通气患者镇静的效果.方法 拟在镇静下行机械通气治疗24 h的重症监护室(ICU)患者60例,年龄20 ～ 64岁,体重指数21 ～ 25 kg/m2,急性生理与慢性健康Ⅱ评分10 ～ 25分,采用随机数字表法,将患者随机分为2组(n=30):咪达唑仑组(M组)和右美托咪定组(D组).M组:静脉注射咪达唑仑0.05 mg/kg负荷量后,以0.03～0.20mg· kg-1·h-1的速率静脉输注;D组:静脉注射右美托咪定1 μg/kg负荷量后,以0.2～0.7μg·kg-1·h-1的速率静脉输注,维持2组Ramsay镇静评分2～4分.记录镇静期间ICU医生对镇静效果的满意度、低血压和心动过缓的发生情况.记录开始镇静至停止镇静后2h谵妄的发生情况、苏醒时间和苏醒后2h内再入睡的发生情况.结果 与M组比较,D组ICU医生对镇静效果的满意度升高,苏醒时间缩短,苏醒后2h内再入睡率和谵妄发生率降低(P＜0.05或0.01),低血压和心动过缓的发生率差异无统计学意义(P＞0.05).结论 右美托咪定用于机械通气患者镇静的效果优于咪达唑仑.     

脑电双频谱指数监测重症监护室机械通气患者镇静水平的准确性

目的 评价脑电双频谱指数(BIS)监测重症监护室机械通气患者镇静水平的准确性.方法 术后未清醒带气管导管送人重症监护室的患者110例,性别不限,年龄18～64岁,体重指数17～29 kg/m2,术前格拉斯哥昏迷评分≥12分,入重症监护室时急性生理学与慢性健康状况评分系统Ⅱ评分为4～18分.静脉输注吗啡0.01～0.05 mg·kg-1·h-1,采用Prince-Henry评分评价疼痛程度,维持Prince-Henry评分1或2分.采用镇静-躁动评分(SAS评分)评价镇静水平.当SAS评分>4分时,先静脉注射咪达唑仑0.03～0.10 mg/kg,再静脉输注0.04～0.20 mg·kg-1·h-1维持;当SAS评分<2分时,则不用、减量或停用.于入重症监护室即刻、15、30、45 min、1 h及1 h后每隔1 h,记录SAS评分和BIS,直至拔除气管导管.结果 在SAS评分1～5分范围内,BIS随SAS评分的升高而升高(P<0.01),SAS评分与BIS呈正相关(r=0.68,P<0.01).结论 在无明显躁动情况下,BIS可准确地监测重症监护室机械通气患者的镇静水平.     

Desflurane compared with propofol for postoperative sedation in the intensive care unit

Background. We hypothesized that emergence from sedation inpostoperative patients in the intensive care unit would be fasterand more predictable after sedation with desflurane than withpropofol. Methods. Sixty patients after major operations were allocatedrandomly to receive either desflurane or propofol. The targetlevel of sedation was defined by a bispectral index^TM (BIS^TM)of 60. All patients were receiving mechanical ventilation ofthe lungs for 10.6 (SD 5.5) h depending on their clinical state.The study drugs were stopped abruptly in a calm atmosphere withthe fresh gas flow set to 6 litres min^–1, and the timeuntil the BIS increased above 75 was measured (t_BIS75, the mainobjective measure). After extubation of the trachea, when thepatients could state their birth date, they were asked to memorizefive words. Results. Emergence times were shorter (P<0.001) after desfluranethan after propofol (25th, 50th and 75th percentiles): t_BIS75,3.0, 4.5 and 5.8 vs 5.2, 7.7 and 10.3 min; time to first response,3.7, 5.0 and 5.7 vs 6.9, 8.6 and 10.7 min; time to eyes open,4.7, 5.7 and 8.0 vs 7.3, 10.5 and 20.8 min; time to squeezehand, 5.1, 6.5 and 10.2 vs 9.2, 11.1 and 21.1 min; time to trachealextubation, 5.8, 7.7 and 10.0 vs 9.7, 13.5 and 18.9 min; timeto saying their birth date, 7.7, 10.5 and 15.5 vs 13.0, 19.4and 31.8 min. Patients who received desflurane recalled significantlymore of the five words. We did not observe major side-effectsand there were no haemodynamic or laboratory changes exceptfor a more marked increase in systolic blood pressure afterstopping desflurane. Using a low fresh gas flow (air/oxygen1 litre min^–1), pure drug costs were lower for desfluranethan for propofol (95 vs 171 Euros day^–1). Conclusions. We found shorter and more predictable emergencetimes and quicker mental recovery after short-term postoperativesedation with desflurane compared with propofol. Desfluraneallows precise timing of extubation, shortening the time duringwhich the patient needs very close attention. Br J Anaesth 2003; 90: 273–80     

模拟人体生物钟镇静用于ICU机械通气患者的临床研究

目的探讨模拟人体生物钟镇静方案对ICU机械通气患者谵妄及其他临床结局的影响。方法将110例ICU有创机械通气≥12h患者根据是否应用模拟人体生物钟镇静方案分为模拟人体生物钟组(研究组,55例)与非模拟人体生物钟组(对照组,55例),两组再根据使用镇静药物的不同分为右美托咪定组(各15例)、丙泊酚组(各20例)、右美托咪定+丙泊酚组(联合镇静组,各20例)。应用重症监护疼痛观察工具(CPOT)及Richmond躁动-镇静评分(RASS)对镇痛镇静深度进行量化控制,使研究组RASS评分白天维持在0~1分、夜间维持在-1~-2分;对照组昼夜均维持在-1~-2分。记录患者谵妄、呼吸机相关性肺炎等并发症或不良事件发生率,以及机械通气时间、住ICU时间、拔管时间、镇痛镇静药物用量。结果研究组谵妄、呼吸机相关性肺炎、严重低血压及心动过缓发生率显著低于对照组(P0.05,P0.01);与同种镇静药的对照组比较,研究组机械通气时间、拔管时间、住ICU时间显著缩短,镇痛镇静药物剂量显著减少(均P0.05)。结论模拟人体生物钟镇静有助于降低ICU机械通气患者不良反应发生率,缩短机械通气时间、拔管时间及住ICU时间,减少镇静镇痛药物用量,可提高临床疗效。     

异丙酚和咪达唑仑用于颅脑创伤患者机械通气镇静对垂体前叶激素影响的比较

目的 比较异丙酚和咪达唑仑用于颅脑损伤患者机械通气镇静对垂体前叶激素的影响.方法 ICU颅脑创伤成年患者84例,拟在镇静下行机械通气治疗,采用随机数字表法,将其随机分为2组(n=42):异丙酚组(P组)和咪达唑仑组(M组).P组静脉输注异丙酚1.5～6.0mg· kg-1·h-1,加深镇静时静脉注射异丙酚50 mg;M组静脉输注咪达唑仑0.10～0.35 mg·kg-1·h-1,加深镇静时静脉注射咪达唑仑7.5 mg.维持Ramsay镇静评分2～4分,行机械通气72～120 h.记录镇静前格拉斯哥昏迷评分、入ICU后4周格拉斯哥预后评分,于镇静24、72 h时和入ICU后4周采集静脉血样,采用ELISA法测定血清皮质醇(COR)、促甲状腺激素(TSH)、泌乳素(PRL)和生长激素(GH)水平.结果 与M组比较,P组镇静24、72 h时血清COR和GH水平降低,TSH水平升高(P＜0.05或0.01),而以上指标水平均维持于正常范围.2组PRL水平及预后良好率之间差异无统计学意义(P＞0.05).结论 异丙酚与咪达唑仑用于颅脑创伤患者机械通气镇静对垂体前叶内分泌功能的影响无显著差异.     

Electroencephalograph variables, drug concentrations and sedation scores in children emerging from propofol infusion anaesthesia

BACKGROUND: Inadequate sedation or oversedation are common problems in Paediatric Intensive Care because of wide variations in drug response and the lack of objective tests for sedative depth. We undertook a pilot study to try to identify correlates of propofol drug concentration, electroencephalographic (EEG) variables and observed behaviour during a stepwise reduction in propofol infusion after paediatric cardiac surgery. METHODS: This was a prospective pilot study with 10 children (5 months to 8 years) emerging from propofol anaesthesia following cardiac surgery with cardiopulmonary bypass (CPB). Patients underwent a stepped wake-up from propofol anaesthesia during which the propofol infusion rate was decreased from 4 mg.kg(-1).h(-1) in 1 mg.kg(-1).h(-1) steps at 30 min intervals. EEG variables, propofol blood concentrations and clinical sedation scores (COMFORT scale) were recorded during the stepped wakeup. Analgesia was maintained with a standardized continuous infusion of fentanyl. RESULTS: : Mean (SD) whole blood propofol concentrations at arousal varied considerably [973 ng.ml(-1) (SD 523 ng.ml(-1))]. The summed ratio (SR) of high frequency to low frequency bands correlated with both propofol infusion rate (R2 value=0.47) and propofol blood concentrations (R2 value=0.64). The mean SR in deeply sedated patients was significantly different from that in the 5 min prior to wakening (6.84 vs 1.55, P=0.00002). There was no relationship between COMFORT scores and SR. CONCLUSIONS: In this group of patients receiving opioid analgesia and relatively high doses of propofol, sedation scores were unhelpful in predicting arousal. The SR correlated with propofol blood concentrations and clinical arousal and may have potential as a predictive tool for arousal in children.     

A lack of evidence of superiority of propofol versus midazolam for sedation in mechanically ventilated critically ill patients: a qualitative and quantitative systematic review

Propofol and midazolam are often used for sedation in the intensive care unit. The aim of this systematic review was to estimate the efficacy and harm of propofol versus midazolam in mechanically ventilated patients. A systematic search (Medline, Cochrane Library, Embase, bibliographies), any language, up to June 1999 was performed for reports of randomized comparisons of propofol with midazolam. Data from 27 trials (1624 adults) were analyzed. The average duration of sedation varied between 4 and 339 h. In 10 trials, the duration of adequate sedation was longer with propofol (weighted mean difference 2.9 h; 95% confidence interval [CI], 0.2-5.6 h). In 13 trials (mostly postoperative), sedation lasted 4 to 35 h; in 9 of those, average weaning time from mechanical ventilation with propofol was 0.8-4.3 h; with midazolam it was 1.5-7.2 h (weighted mean difference 2.2 h [95% CI, 0.8 to 3.7 h]). In 8 trials, sedation lasted 54 to 339 h; there was a lack of evidence for difference in weaning times. Arterial hypotension (relative risk 2.5 [95% CI, 1.3 to 4.5]; number-needed-to-treat, 12), and hypertriglyceridemia (relative risk 12.1 [95%CI, 2.9 to 49.7]; number-needed-to-treat, 6) occurred more often with propofol. The duration of adequate sedation time is longer with propofol compared with midazolam. In postoperative patients with sedation <36 h, weaning is faster with propofol. Implications: The duration of adequate sedation time is longer with propofol compared with midazolam. In postoperative patients with sedation < 36 h, weaning is faster with propofol.     

Intrathecal ropivacaine for total hip arthroplasty: double-blind comparative study with isobaric 7.5 mg ml(-1) and 10 mg ml(-1) solutions

This study was designed to evaluate the efficacy and safetyof two concentrations of intrathecal ropivacaine, 7.5 and 10mg ml^–1, in patients undergoing total hip arthroplasty.One hundred and four patients, ASA I–III, were randomizedto receive an intrathecal injection of one of two concentrationsof isobaric ropivacaine. Group 1 (n=51) received 2.5 ml of 7.5mg ml^–1 ropivacaine (18.75 mg). Group 2 (n=53) received2.5 ml of 10 mg ml^–1 ropivacaine (25 mg). The onset andoffset of sensory block at dermatome level T10, maximum upperand lower spread of sensory block and the onset, intensity andduration of motor block were recorded, as were safety data.Onset of motor and sensory block was rapid with no significantdifferences between the two groups. The median time of onsetof sensory block at the T10 dermatome was 2 min (range 1–25min) in Group 1 and 2 min (range 1–21 min) in Group 2.The median duration of sensory block at the T10 dermatome was3.0 h (range 0.5–4.2 h) in Group 1 and 3.4 h (1.1–5.9h) in Group 2 (P=0.002). The median duration of complete motorblock was significantly prolonged (P<0.05) in Group 2 comparedwith Group 1 (1.9 vs 1.2 h, respectively). Anaesthetic conditionswere excellent in all but one patient. Intrathecal ropivacaine,in doses of 18.75 and 25 mg, was well tolerated and providedeffective anaesthesia for total hip arthroplasty. Br J Anaesth 2001; 87: 743–7     

New-onset,postoperative tachyarrhythmias in critically ill surgical patients

Tachyarrhythmias in critically ill surgical patients can have varying effects, from minimal consequence to lifetime sequelae. Atrial fibrillation can be common in the post-operative period, often a result of fluctuations in volume status and electrolyte derangements. While there is extensive literature regarding the critically ill medical or cardiac patient, there is less focusing on the critically ill surgical or trauma patient. More specifically, there is minimal regarding tachyarrhythmias in burn patients. The latter population tends to have frequent and wide variations in volume status given initial resuscitation and after major excisions, concomitant with acute blood loss anemia, which can contribute to cardiac disturbances. A literature review was conducted to investigate the incidence and consequences of tachyarrhythmias in critically ill surgical and trauma patients, with a focus on the burn population. While some similarities and conclusions can be drawn between these surgical populations, further inquiry into the unique burn patient is necessary.     

Spinal anaesthesia for Caesarean section with bupivacaine 5 mg ml(-1) in glucose 8 or 80 mg ml(-1)

The standard spinal preparation of bupivacaine contains a highconcentration of glucose (80 mg ml^–1). However,the addition of only a small amount of glucose (8 mg ml^–1)to plain solutions of bupivacaine results in a solution which,although no more than marginally hyperbaric, produces a morepredictable block when used for spinal anaesthesia in non-pregnantpatients. However, bupivacaine 5 mg ml^–1 inglucose 8 mg ml^–1 has a density [1.00164 (SD0.00008) at 37°C] which is relatively greater than thatof the cerebrospinal fluid (CSF) of the pregnant patient atterm (1.0003 at 37°C) because CSF density decreases duringpregnancy. Therefore, a double-blind, randomized, controlledstudy was carried out to compare intrathecal bupivacaine (glucose8 mg ml^–1) with bupivacaine (glucose 80 mg ml^–1)in 40 pregnant patients at term. Although there was no differencebetween groups in onset of sensory block, dose of ephedrineor patient satisfaction, patients receiving bupivacaine (5 mg ml^–1)with glucose (8 mg ml^–1) had persistently highersensory blocks between 60 and 120 min after intrathecalinjection, suggesting that the spread of spinal solutions inthe pregnant patient at term is not dependent on density. Br J Anaesth 2001; 86: 805–7     

Double-blind comparison of ropivacaine 7.5 mg ml(-1) with bupivacaine 5 mg ml(-1) for sciatic nerve block

Two groups of 12 patients had a sciatic nerve block performedwith 20 ml of either ropivacaine 7.5 mg ml^–1 or bupivacaine5 mg ml^–1. There was no statistically significant differencein the mean time to onset of complete anaesthesia of the footor to first request for post-operative analgesia. The qualityof the block was the same in each group. Although there wasno statistically significant difference in the mean time topeak plasma concentrations the mean peak concentration of ropivacainewas significantly higher than that of bupivacaine. There wereno signs of systemic local anaesthetic toxicity in any patientin either group. Br J Anaesth 2001; 86: 674–7     

Comparison of ropivacaine 2 mg ml(-1) and prilocaine 5 mg ml(-1) for i.v. regional anaesthesia in outpatient surgery

Background. Ropivacaine 2 mg ml^–1 (0.2%) provides longer-lastinganalgesia after deflation of the tourniquet cuff, with fewerside-effects, than lidocaine 5 mg ml^–1 (0.5%) after i.v.regional anaesthesia (IVRA). Whether ropivacaine 2 mg ml^–1also exerts this advantage over prilocaine 5 mg ml^–1,the local anaesthetic of choice in IVRA in most European countrieswas investigated in this study. Methods. Sixty outpatients scheduled for forearm or hand surgeryreceived IVRA with 40 ml of ropivacaine 2 mg ml^–1 (Ropi)or prilocaine 5 mg ml^–1 (Prilo) in a randomized, double-blindedfashion. The development and recovery of pin-prick analgesiaand motor power of the hand, as well as ropivacaine and prilocaineplasma concentrations (n=30), were assessed during and afteroperation. Results. Anaesthesia for surgery was adequate in both groups.Pin-prick analgesia was achieved at a similar rate, except inthe radial nerve distribution area where at 10 min 60% of Ropiand 90% of Prilo patients had analgesia (P=0.017). At 10 min100 and 97% had motor block of the hand in the Ropi and Prilogroups, respectively. Recovery of the sensory block in all innervationareas was already observed 2 min after the tourniquet cuff release.At 10 min after releasing the tourniquet cuff 31% of the Ropipatients and none of the Prilo patients still had analgesiain the median nerve distribution (P=0.004). At 12 min, 42% inthe Ropi group and none in the Prilo group had decreased gripstrength. After the release of the tourniquet, mean plasma concentrationsof ropivacaine were higher than those of prilocaine. The highestindividual concentration of ropivacaine was 1.65 µg ml^–1and that of prilocaine 0.6 µg ml^–1. None of theRopi patients experienced any symptoms of local anaesthetictoxicity. Conclusions. Compared with prilocaine 5 mg ml^–1, analgesiain IVRA with ropivacaine 2 mg ml^–1 developed slightlymore slowly, while motor block developed at a similar rate.After the release of the tourniquet, sensation recovered quicklyand at a similar rate in the two groups, except for a slightlyslower recovery after ropivacaine in the innervation area ofthe median nerve, but no surgically useful extended analgesiaafter the cuff deflation was observed. Despite a 60% lower milligram-dose,ropivacaine plasma concentrations were markedly higher thanthose of prilocaine.     

Propofol induces bronchodilation in mechanically ventilated chronic obstructive pulmonary disease (COPD) patients

The aim of this study was to evaluate the effects of propofol administration (2 mg · kg^-1 i.v.) on the airways resistances and respiratory mechanics of patients affected by COPD exacerbation, requiring mechanical ventilation. Twenty patients required anaesthesia for diagnostic or therapeutic procedures. Fourteen consecutive patients were divided at random into two groups: Group P received propofol and Group C (control) received only Intralipid 10%; an additional group of six patients received i.v. flunitrazepam (0.03 mg · kg^-1). Lung mechanics (dynamic and static compliance, peak inspiratory pressure, intrinsic positive and expiratory pressure, minimal and maximal resistances of the respiratory system) were evaluated in basal conditions and 3 and 6 min after propofol, Intralipid or flunitrazepam administration. We did not observe significant variations of the evaluated variables after Intralipid or flunitrazepam (Groups C and F), while in patients who received propofol (Group P), we observed the following modifications: dynamic compliance increased from 2.3 ± 0.3 to 2.8 ± 0.4 ml · kPa^-1 (P<0.05), peak inspiratory pressure decreased from 3.3 ± 0.7 to 2.8 ± 0.4 kPa (P <0.05), minimal resistances of the respiratory system (that mainly reflect airways resistances) decreased from 1 ± 0.2 to 0.7 ± 0.2 kPa · 1^-1 · s^-1 (P <0.01). Our results suggest that propofol induces bronchodilation in mechanically ventilated COPD patients, and that this effect is not related specifically to the induction of general anesthesia.     

What,why and how to monitor blood glucose in critically ill patients

Critically ill patients are prone to high glycemic variations irrespective of their diabetes status. This mandates frequent blood glucose (BG) monitoring and regulation of insulin therapy. Even though the most commonly employed capillary BG monitoring is convenient and rapid, it is inaccurate and prone to high bias, overestimating BG levels in critically ill patients. The targets for BG levels have also varied in the past few years ranging from tight glucose control to a more liberal approach. Each of these has its own fallacies, while tight control increases risk of hypoglycemia, liberal BG targets make the patients prone to hyperglycemia. Moreover, the recent evidence suggests that BG indices, such as glycemic variability and time in target range, may also affect patient outcomes. In this review, we highlight the nuances associated with BG monitoring, including the various indices required to be monitored, BG targets and recent advances in BG monitoring in critically ill patients.