控制气管导管套囊压力对全麻手术患者气管插管相关性并发症的影响:前瞻性、多中心、随机、双盲研究

目的 探讨控制气管导管套囊压力对全麻手术患者气管插管相关性并发症的影响.方法 本研究为前瞻性、多中心、随机、双盲研究.择期拟行全麻手术患者509例,ASA分级Ⅰ或Ⅱ级,年龄11～89岁,体重35～92kg,性别不限,随机分为2组:对照组(C组)和套囊压力测定组(CPM组),记录手术时间和带管时间.各组随机选取20例带管时间120～180 min的患者,于拔除气管导管时行纤维支气管镜检查.拔除气管导管后24 h内随访咳嗽及痰中带血等气管插管相关性并发症的发生情况.结果 两组患者年龄、性别构成比、手术时间及带管时间差异无统计学意义(P＞0.05).与C组比较,CPM组患者咽喉痛及痰中带血的发生率降低(P＜0.05);随带管时间延长,C组咽喉痛及痰中带血的发生率均升高,CPM组仅咽喉痛的发生率升高(P＜0.01).纤维支气管镜检查可见气管粘膜不同程度损伤,C组较CPM组严重.结论 控制气管导管套囊压力有助于减少全麻手术患者术后气管插管相关性并发症的发生.     

ProSeal喉罩用于体外循环心内直视术患儿气道管理的效果

目的 评价ProSeal喉罩用于体外循环心内直视术患儿气道管理的效果.方法 择期拟行心内直视术患儿76例,年龄3月～8岁,体重3.3～34.5 kg,性别不限,ASA分级Ⅱ级,心功能分级Ⅰ或Ⅱ级,随机分为2组(n=38):气管导管组(T组)和ProSeal喉罩组(P组).麻醉诱导后,T组置入气管导管,P组置入ProSeal喉罩,行机械通气.记录气管导管和喉罩的置入情况、置入时间、最高气道压、术中低氧血症、心动过速、心动过缓、低血压和高血压的发生情况、术后喉头水肿、吞咽困难、呛咳、呼吸困难、声音嘶哑的发生情况.结果 气管导管和ProSeal喉罩全部置入成功.两组术中均未见低氧血症、心动过速、心动过缓、低血压和高血压的发生.与T组比较,P组置入时间缩短,喉头水肿和吞咽困难的发生率降低(P＜0.05),最高气道压、呛咳、呼吸困难和声音嘶哑的发生率差异无统计学意义(P＞0.05).结论ProSeal喉罩置入简单易行,可有效保证通气,对咽喉部刺激较小,用于体外循环心内直视术患儿的气道管理安全可靠.     

心肺转流对血管内皮细胞功能和肿瘤坏死因子的影响

目的 探讨心肺转流(CPB)对血管内皮细胞(VEC)功能和肿瘤坏死因子α(TNF-α)的影响. 方法 24例择期手术的先天性心脏病患者,分为两组:A组(n=14)在CPB下行心内直视手术;B组(n=10)在非CPB下行心内直视手术.于麻醉前(T1)、术毕(T2)、术后6(T3)、24 h(T4)采集桡动脉血,测定血浆中NO-2/NO-3、内皮素-1(ET-1)、丙二醛(MDA)和TNF-α的水平.结果 与B组比较,A组ET-1水平在T2和T3时点明显升高(P＜0.01),到T4时恢复术前水平;A组T2时点血浆NO-2/NO-3水平明显低于B组(P＜0.05).A组T2、T3时MDA浓度均高于B组(P＜0.05).与术前相比,A组血浆TNF-α浓度在T2～T4时均持续升高(P＜0.01).结论 CPB可致VEC功能活化,使血浆ET-1/NO平衡失调.     

不同剂量丙泊酚持续静注对心内直视手术病人肌钙蛋白I的影响

目的观察不同剂量丙泊酚对心内直视术病人肌钙蛋白-Ⅰ(CTn-Ⅰ)的影响,寻求丙泊酚抑制心肌缺血再灌注损伤作用合适的剂量.方法27例心内直视手术患者随机分成A、B、C三组.咪唑安定、丙泊酚、维库溴铵、芬太尼诱导后,用微量泵持续输注丙泊酚,A组2mg@kg-1@h-1、B组5mg@kg@h-1、C组8mg@kg-1@h-1.用化学发光法测定诱导后、停心肺转流(CPB)即刻、CPB后30、60分钟和CPB后3小时动脉血CTn-Ⅰ浓度.结果三组病人CPB后CTn-Ⅰ均显著升高(P＜0.01).组间比较,B组CPB后CTn-Ⅰ值比A组低(P＜0.05和P＜0.01).C组和A组间CTn-Ⅰ值无统计学差异.结论心脏手术术中及术后CTn-Ⅰ升高提示心肌存在不同程度损伤.术中5mg@kg@h-1丙泊酚持续静注是较为理想的具有心肌保护作用的临床用药剂量.     

喉罩全身麻醉复合骶管阻滞在非洲儿童手术中的应用

目的 观察喉罩全身麻醉复合骶管阻滞与单纯气管插管全身麻醉在非洲儿童手术中的应用,为儿童麻醉提供参考. 方法 4～6岁行下腹部及下肢部位择期手术的患儿60例,完全随机分为喉罩全身麻醉复合骶管阻滞麻醉组(A组)和单纯气管插管全身麻醉组(B组),每组30例.观察记录患儿麻醉诱导前(T0)、置入喉罩/气管导管前后(T1、T2)及术毕拔出喉罩/气管导管(T3)时的MAP、HR和Sp02,以及麻醉苏醒时间、术后VAS疼痛评分及副作用情况. 结果 两组患儿MAP、HR和Sp02在To和T1时比较,差异无统计学意义(P＞0.05);A组MAP和HR[(68±10) mmHg(1 mmHg=0.133 kPa)、(108±17)次/min]在T2时明显低于B组[(91±8) mmHg、(139±18)次/min] (P＜0.05);A组MAP和HR[(67±9) mmHg、(121±16)次/min]在T3时也明显低于B组[(85±9) mmHg、(141±17)次/min] (P＜0.05);A组术后VAS评分[(1.5±0.5)分]明显低于B组[(6.5±1.5)分](P＜0.05),A组苏醒时间[(5.8±2.4)min]明显短于B组[(12.2±2.8) min](P＜0.05),A组术后躁动(4例)明显低于B组(17例)(P＜0.05),术后A组啼哭和呛咳的发生率也明显低于B组(P＜0.05). 结论 喉罩全身麻醉复合骶管阻滞麻醉在患儿诱导期和苏醒期有更加平稳的血流动力学,且术后疼痛明显降低、苏醒时间明显缩短、术后副作用发生率明显降低,是非洲儿童下腹部及下肢部位手术的一种较理想的麻醉方法.     

Ⅰ-Gel喉罩联合气管导管和支气管封堵器在食管癌根治术单肺通气中的应用

目的 探讨Ⅰ-Gel喉罩联合气管导管和支气管封堵器在食管癌根治术单肺通气的可行性和效果. 方法 择期行食管癌根治手术患者60例,年龄40岁～80岁,美国麻醉医师协会(ASA)分级Ⅰ-Ⅲ级,采用随机数字表法分为3组(每组20例):双腔支气管导管组(D组)、单腔气管导管联合支气管封堵器组(B组)、Ⅰ-Gel喉罩联合气管导管和支气管封堵器组(Ⅰ组).记录各组支气管封堵器或双腔支气管导管的定位时间、术中支气管封堵器或双腔支气管导管移位的次数、肺萎陷的程度及单肺通气的气道峰压,记录诱导前(T0)、气管插管或喉罩置人前(T1)、气管插管或喉罩置入后1 min (T2)、气管插管或喉罩置入后5 min(T3)、术后气管导管或喉罩拔除前5 min(T4)、拔管或喉罩拔除后1 min(T5)、拔管或喉罩拔除后5 min(T6)患者的血压、心率及拔管或喉罩期间的呛咳例数,记录术后2d内患者咽痛、声音嘶哑等副作用. 结果 Ⅰ组除T1时收缩压(117±9) mmHg(1 mmHg=0.133 kPa)和舒张压(65±9) mmHg低于术前收缩压(145±12) mmHg和舒张压(75±9) mmHg(P＜0.05)外,诱导期间及术后恢复期各时点患者血压与术前比较差异无统计学意义(P＞0.05),B组和D组麻醉插管后及术后恢复期T2～T6时患者心率及血压高于术前(P＜0.05);Ⅰ组(0例)拔管期间呛咳反应少于B组(8例)和D组(15例)(P＜0.05);Ⅰ组(O例)术后咽痛和声嘶的发生例数低于D组(16例)、B组(7例)(P＜0.05).Ⅰ组定位时间(4.2±1.2) min长于B组(2.8±0.7) min和D组(2.7±0.4) min(P＜0.05),D组、B组和Ⅰ组术中移位例数及肺萎陷程度相似(P＞0.05),Ⅰ组[(22±3) mmHg]和B组[(21±4) mmHg]单肺通气期间气道峰压力低于于D组[(28±4) mmHg](P＜0.05),而Ⅰ组和B组气道峰压差异无统计学意义(P＞0.05). 结论 Ⅰ-Gel喉罩联合气管导管和支气管封堵器可减轻全身麻醉诱导期和苏醒期的刺激,可安全用于食管癌根治术中气管管理.     

不同浓度七氟醚对静态膨肺患者心肺转流后肺气体交换的影响

目的评价不同浓度七氟醚静态膨肺对心肺转流(cardiopulmonary bypass,CPB)后肺气体交换及术后气管留管时间的影响。方法择期行CPB下瓣膜置换手术患者75例,男39例,女36例,年龄22～65岁,ASAⅡ或Ⅲ级。采用随机数字表法将患者随机分为三组:每组25例。CPB期间停止呼吸后,予持续静态膨胀,呼吸环路压力维持10cmH2O,膨肺气体采用空气,分别复合吸入1%七氟醚(L组)或2%七氟醚(H组),对照组(N组)不复合吸入七氟醚。分别于切皮前、CPB停机后1、3、6h抽取动脉血行血气分析。计算肺泡-动脉氧分压差[D(A-a)O_2]、呼吸指数(RI)和氧合指数(OI)。记录术后气管留管时间和ICU留观时间。结果与切皮前比较,CPB停机后1、3、6h三组D(A-a)O_2、RI明显升高(P0.05);CPB停机后1h三组OI明显降低(P0.05)。三组不同时点D(A-a)O_2、RI和OI差异无统计学意义。三组CPB停机后1、3、6h发生OI300mmHg的比例、术后气管留管时间和ICU留观时间差异无统计学意义。结论心脏瓣膜置换手术CPB期间,静态膨肺采用10cmH2O压力,复合吸入1%或2%浓度七氟醚,与单纯静态膨肺比较,不能进一步改善CPB后患者肺气体交换,不影响术后气管留管时间和ICU留观时间。     

盐酸氨溴索对体外循环心内直视手术患儿肺损伤的影响

目的 评价盐酸氨溴索对体外循环(CPB)心内直视手术患儿肺损伤的影响.方法 36例拟行室间隔缺损修补术患儿,年龄3～8岁,随机分为3组(n=12),A1组和A2组切皮后即刻分别静脉注射盐酸氨溴索2.25、4.50 ms/ks,C组给予等容量生理盐水.分别于切皮前即刻、CPB 20 min、开放升主动脉20 min停机2 h、停机6 h和术后12 h采集桡动脉血样,测定血浆丙二醛(MDA)浓度和超氧化物歧化酶(SOD)活性,并进行血气分析,计算呼吸指数(RI)和肺顺应性(CL).结果 与C组及A1组比较,A2组血浆MDA浓度和RI降低,血浆SOD活性升高(P＜0.05或0.01);A2组CL高于C组(P＜0.05).结论 盐酸氨溴索4.50 mg/kg可减轻CPB心内直视手术患儿肺损伤,其机制与减轻脂质过氧化反应有关.     

急性血小板分离回输对体外循环心脏直视手术患者的血液保护效果

目的 评价急性血小板(Plt)分离回输对体外循环(CPB)心脏直视手术患者的血液保护效果.方法 择期拟在CPB下行心脏直视手术患者30例,ASA分级Ⅱ或Ⅲ级,年龄41～63岁,体重52～72 kg.采用随机数字表法,将患者随机分为2组(n=15):对照组(C组)和急性Plt分离组(APP组).APP组在麻醉诱导后行APP,提取富Plt血浆,于CPB结束鱼精蛋白中和肝索后回输,C组不行APP.于麻醉诱导前、术后1、24和48h时记录Hb、Plt、PT、APTT及Fib.记录CPB时间、主动脉阻断时间、术后引流量和输血情况.结果 APP组急性Plt分离处理的全血容量为(1285±185) ml,采集富Plt血浆(192±38) ml,其中Plt计数(817±282)×10/L,占全身血容量Plt总数(21±3)％,Plt分离时间(35±10) min.与C组比较,APP组术后1h时Plt升高,术后24h内引流量、异体红细胞、Plt输注量和异体Ph输注率降低(P＜0.05或0.01),其余指标差异无统计学意义(P＞0.05).结论 急性Plt分离回输对CPB心脏直视手术患者具有血液保护作用.     

体外循环对单核细胞HLA-DR表达的影响

目的研究体外循环对单核细胞表面HLA-DR表达水平的影响.方法16例风湿性心脏病瓣膜置换术患者为试验组(心内直视术组),10例肺叶切除术患者为对照组(非心内直视术组).采用流式细胞术动态观察麻醉诱导前、气管插管后、体外循环心肺转流前、体外循环心肺转流后、手术后第1d、第3d及第5d淋巴细胞和单核细胞表面HLA-DR的表达水平,同时观察APACHEⅡ评分及手术后恢复情况.结果心内直视术组心肺转流后、术后第1d、第3dHLA-DR表达阳性的单核细胞百分率显著下降,且心肺转流后单核细胞数显著下降,单核细胞表面的HLA-DR分子数显著下降(P＜0.05).肺叶切除术组手术后HLA-DR表达阳性的单核细胞百分率明显下降,但单核细胞占外周血白细胞比例无显著性差异.HLA-DR表达阳性的淋巴细胞百分率在各个时间点均无统计学差异(P＞0.05);两组相比,手术后HIA-DR表达阳性的单核细胞百分率心内直视组显著低于肺叶切除组.2例心内直视术后并发感染患者于术后第6dHLA-DR表达阳性的单核细胞百分率仍低于40%.结论心肺转流后机体免疫功能的障碍与单核细胞的功能紧密相关.动态监测单核细胞表面HLA-DR的表达水平有助于预测心内直视术后感染的发展及预后.     

Intracuff pressure and tracheal morbidity: influence of filling with saline during nitrous oxide anesthesia.

BACKGROUND: Diffusion of nitrous oxide into the cuff of the endotracheal tube results in an increase in cuff pressure. Excessive endotracheal tube cuff pressure may impair tracheal mucosal perfusion and cause tracheal damage and sore throat. Filling the cuff of the endotracheal tube with saline instead of air prevents the increase in cuff pressure due to nitrous oxide diffusion. This method was used to test whether tracheal morbidity is related to excess in tracheal cuff pressure during balanced anesthesia. METHODS: Fifty patients with American Society of Anesthesiologists physical status I or II were randomly allocated to two groups with endotracheal tube cuffs initially inflated to 20-30 cm H(2)O with either air (group A) or saline (group S). Anesthesia was maintained with isoflurane and nitrous oxide. At the time of extubation, a fiberoptic examination of the trachea was performed by an independent observer, and abnormalities of tracheal mucosa at the level of the cuff contact area were scored. Patients assessed their symptoms (sore throat, dysphagia, and hoarseness) at the time of discharge from the postanesthesia care unit and 24 h after extubation on a 101-point numerical rating scale. RESULTS: Cuff pressure increased gradually during anesthesia in group A but remained stable in group S. The incidence of sore throat was greater in group A than in group S in the postanesthesia care unit (76 vs. 20%) and 24 h after extubation (42 vs. 12%; P < 0.05). Tracheal lesions at time of extubation were seen in all patients of group A and in eight patients (32%) of group S (P < 0.05). CONCLUSION: Excess in endotracheal tube cuff pressure during balanced anesthesia due to nitrous oxide diffusion into this closed gas space causes sore throat that is related to tracheal mucosal erosion.     

Intracuff Pressure and Tracheal Morbidity: Influence of Filling Cuff with Saline during Nitrous Oxide Anesthesia

Background : Diffusion of nitrous oxide into the cuff of the endotracheal tube results in an increase in cuff pressure. Excessive endotracheal tube cuff pressure may impair tracheal mucosal perfusion and cause tracheal damage and sore throat. Filling the cuff of the endotracheal tube with saline instead of air prevents the increase in cuff pressure due to nitrous oxide diffusion. This method was used to test whether tracheal morbidity is related to excess in tracheal cuff pressure during balanced anesthesia.

Methods : Fifty patients with American Society of Anesthesiologists physical status I or II were randomly allocated to two groups with endotracheal tube cuffs initially inflated to 20-30 cm H2O with either air (group A) or saline (group S). Anesthesia was maintained with isoflurane and nitrous oxide. At the time of extubation, a fiberoptic examination of the trachea was performed by an independent observer, and abnormalities of tracheal mucosa at the level of the cuff contact area were scored. Patients assessed their symptoms (sore throat, dysphagia, and hoarseness) at the time of discharge from the postanesthesia care unit and 24 h after extubation on a 101-point numerical rating scale.

Results : Cuff pressure increased gradually during anesthesia in group A but remained stable in group S. The incidence of sore throat was greater in group A than in group S in the postanesthesia care unit (76 vs. 20%) and 24 h after extubation (42 vs. 12%;P < 0.05). Tracheal lesions at time of extubation were seen in all patients of group A and in eight patients (32%) of group S (P < 0.05).     

Air leakage around endotracheal tube cuffs

BACKGROUND AND OBJECTIVE: To compare the recently introduced Microcuff endotracheal tube with conventional tubes in respect of the cuff pressures required to prevent air leakage. METHODS: The following tubes (ID 7.0mm) were compared: Microcuff HVLP ICU, Mallinckrodt HiLo, Portex Profile Soft Seal, Rüsch Super Safety Clear and Sheridan CF. Fifty patients undergoing endotracheal intubation with a cuffed tube of internal diameter 7.0 mm were studied. Tracheas were intubated using one of the endotracheal tubes in random order. Cuff pressure to prevent air leakage at standardized ventilator setting (peak inspiratory pressure 20 cmH2O/PEEP 5 cmH2O/respiratory rate 15 breaths min(-1)) was assessed by auscultation of audible sounds at the mouth. Patients characteristics and cuff pressures from each brand were compared to the Microcuff group using the Mann-Whitney U-test (P < 0.05 was chosen as the level of statistical significance). RESULTS: Patients' median age (range) was 14.2 (12.0-17.1) yr, body weight 57.5 (40.0-81.9) kg and length 164.9 (146.5-190.0) cm. No significant differences in patients' characteristics were found between groups. Mean cuff pressure (all tubes) required for air sealing was 19.1 (8-42) cmH2O. The Microcuff tube required significantly lower sealing pressures (9.5 (8-12) cmH2O) compared to the other brands of endotracheal tube (P < 0.05, Mann-Whitney U-test). CONCLUSION: The Microcuff endotracheal tube with its ultra-thin polyurethane cuff membrane required the lowest sealing pressure to prevent air leakage. These features are potentially of interest for long-term intubated patients and for cuffed endotracheal tubes in children, allowing tracheal sealing at lower cuff pressures implying less damage to the trachea.     

Detection of tracheal malpositioning of nasogastric tubes using endotracheal cuff pressure measurement

BACKGROUND: Insertion of a gastric tube (GT) in anaesthetized, paralyzed and intubated patients may be difficult. Tracheobronchial malposition of a GT may result in deleterious consequences. The purpose of this study was to determine the reliability of tracheal cuff pressure measurement to detect endobronchial malposition of GTs. We compared this new method with the measurement of exhaled CO(2) through the GT. METHODS: Thirty patients under general anesthesia and orotracheal intubation were analysed. First, the cuff pressure of the low-volume endotracheal tube (ET; ID 7.0-8.5 mm) was increased to 40 cmH(2)O. Then, in a randomized fashion, the GT (18 Charrière) was inserted consecutively into the trachea and oesophagus or vice versa. Cuff pressure was monitored continuously while advancing the GT. Furthermore, a capnograph was connected to the gastric tube and the aspirated PCO(2) was monitored. RESULTS: Advancement of the gastric tube into the oesophagus increased ET cuff pressure by 1 +/- 1 cmH(2)O, while endotracheal placement of the GT increased cuff pressure by 28 +/- 8 cmH(2)O (P < 0.001). Using an increase of >10 cmH(2)O in cuff pressure detected endotracheal malpositioning of the GT with 100% sensitivity and specificity. In 28 out of 30 cases, PCO(2) increased by more than 2.6 kPa. Thus, the PCO(2) approach failed to detect tracheal malpositioning in two cases resulting in a sensitivity of 93.3%. CONCLUSIONS: In intubated patients, cuff pressure measurement during insertion of a gastric tube is a new, simple and reliable bedside method to detect endotracheal malpositioning of a GT.     

Laryngeal and respiratory responses to tracheal irritation at different depths of enflurane anesthesia in humans

The effect of three different depths of enflurane anesthesia (1.0, 1.4, and 1.8 MAC) upon laryngeal and respiratory responses to tracheal instillation of distilled water in nine female patients in whom a double-cuffed endotracheal tube had been inserted was investigated. The laryngeal responses were monitored by measuring the pressure in the saline-filled cuff positioned within the larynx, and the respiratory responses were monitored by measuring ventilatory flow and tracheal airway pressure. Increases in laryngeal cuff pressure in response to tracheal irritation were 19.7 +/- 4.5 cmH2O (mean +/- SD) at 1.0 MAC, 13.9 +/- 3.6 cmH2O at 1.4 MAC, and 7.6 +/- 1.8 cmH2O at 1.8 MAC, respectively (P less than 0.01 for anesthetic dose). At 1.0 MAC of enflurane anesthesia, tracheal instillation of saline caused immediate laryngeal constriction and all components of the tracheal response, such as apnea, expiration reflex, cough reflex, and spasmodic panting. At 1.4 and 1.8 MAC, the same stimulation caused only apnea and constriction of the larynx in the majority of patients. These results indicate that changes in depth of anesthesia can modify the laryngeal and respiratory responses to tracheal irritation. The close association of laryngeal and respiratory responses may be an integral part of the defensive reflex synergism.     

Influence of temperature on tracheal tube cuff pressure during cardiac surgery

BACKGROUND: Lateral wall pressure may cause tracheal injury by affecting tracheal capillary blood flow. Damage to the trachea is less severe when lateral wall pressure exerted by the endotracheal tube cuff does not exceed the mean capillary perfusion pressure of the mucosa. The purpose of this study was to determine the effects of hypothermic and normothermic cardiopulmonary bypass (CPB) on tracheal tube cuff pressure dynamics. METHODS: Twenty-two patients were studied during normothermic CPB (pulmonary artery blood temperature in the CPB period between 36 and 35 degrees C), and 22 patients during hypothermic CPB (pulmonary artery temperature in the CPB period between 32 and 28 degrees C). A Mallinckrodt Medical Lo-Contour Murphy tracheal tube, with high-volume, low-pressure cuff was used without lubricant. Intracuff pressure (ITCP) was recorded at end-expiration before, during and after cardiopulmonary bypass. RESULTS: ITCP measurements were different between groups during CPB at aortic cross-clamping (13.9 +/- 0.8 mmHg in the normothermic group versus 11.3 +/- 0.4 mmHg in the hypothermic group, P < 0.05), and respectively during CPB after aortic declamping (15.3 +/- 0.8 mmHg and 12.6 +/- 0.8 mmHg, P < 0.05) and after CPB at the end of surgery (16.8 +/- 0.7 mmHg and 18.6 +/- 0.3 mmHg, P < 0.05). CONCLUSION: We conclude that the ITCP is higher in normothermic CPB than in hypothermic CPB; however, the clinical significance of this observation needs further investigation.     

Nitrous oxide increases endotracheal cuff pressure and the incidence of tracheal lesions in anesthetized patients.

The pressure in air-filled endotracheal cuffs increases steadily throughout general anesthesia with nitrous oxide (N2O). High cuff pressures can be responsible for local ischemia, which may induce tracheal mucosal injury. In this study, cuff pressure was monitored in anesthetized patients, and postanesthesia endotracheal lesions were assessed by endoscopy. Sixty-five patients undergoing general anesthesia with tracheal intubation >1 h in duration were randomized into two groups. The endotracheal tube cuff was inflated to 30-40 cm H2O with air in Group 1 (n = 33) and with a gas mixture (N2O 50% in oxygen) in Group 2 (n = 32). At the time of tracheal extubation, a fiberoptic examination via the endotracheal tube was performed by an independent observer. Aspects of trachea at the level of cuff contact area were scored as 0 = normal, 1 = mucosal erythema or edema, 2 = mucosal erosion or hemorrhage, 3 = mucosal erosion or hemorrhage on both anterior and posterior tracheal walls. Cuff pressure increased throughout the procedure (P<0.01) in Group 1 and remained stable in Group 2. In Group 1, tracheal lesions in the area of the cuff were more frequent than they were in Group 2 (79% vs. 37%; P<0.001). Tracheal injury was correlated to cuff pressure (r = 0.62, P<0.001). No postoperative respiratory complication was observed in any patient. In patients anesthetized with N2O, the inflation of the tracheal tube cuff with a gas mixture of the same composition as the inhaled mixture can prevent excessive cuff pressure and reduce the incidence of tracheal injury. IMPLICATIONS: In patients anesthetized with nitrous oxide, the inflation of the tracheal tube cuff with a gas mixture of the same composition as the inhaled mixture can prevent excessive cuff pressure and reduce the incidence of tracheal injury.     

Does sealing endotracheal tube cuff pressure diminish the frequency of postoperative laryngotracheal complaints after nitrous oxide anesthesia?

STUDY OBJECTIVES: To study endotracheal tube (ETT) cuff pressures during nitrous oxide (N2O) anesthesia when the cuffs are inflated with air to achieve sealing pressure, and to evaluate the frequency of postoperative laryngotracheal complaints. DESIGN: Prospective, randomized, blind study. SETTING: Metropolitan teaching hospital. PATIENTS: 50 ASA physical status I and II patients scheduled for elective abdominal surgery. INTERVENTIONS: Patients received standard general anesthesia with 66% N2O in oxygen. In 25 patients, the ETT cuff was inflated with air to achieve a sealing pressure (Pseal group). In 25 patients, the ETT cuff was inflated with air to achieve a pressure of 25 cm H2O (P25 group). MEASUREMENTS AND MAIN RESULTS: ETT intracuff pressures were recorded before (control) and at 30, 60, 90, 120, and 150 minutes during N2O administration. We investigated the frequency and intensity of sore throat, hoarseness, and dysphagia in patients in the Post-Anesthesia Care Unit (PACU) and 24 hours following tracheal extubation. The cuff pressures in the Pseal group were significantly lower than in the P25 group at all time points studied (p < 0.001), with a significant increase with time in both groups (p < 0.001). The cuff pressures exceeded the critical pressure of 30 cm H2O only after 90 minutes in the Pseal group and already by 30 minutes in the P25 group. The frequency and intensity of sore throat, hoarseness, and dysphagia were similar in both groups in the PACU and 24 hours after tracheal extubation (p > 0.05). CONCLUSIONS: Minimum ETT sealing cuff pressure during N2O anesthesia did not prevent, but instead attenuated, the increase in cuff pressure and did not decrease postoperative laryngotracheal complaints.     

Ⅰ-gel喉罩应用于面神经显微血管减压术的临床观察

目的 评价Ⅰ-gel喉罩用于面神经显微血管减压术气道管理的效果.方法 择期行面神经显微血管减压术患者90例,性别不限,年龄20～55岁,BMI 18～25 kg/m2,ASA分级Ⅰ、Ⅱ级,Mallampati分级Ⅰ～Ⅲ级,完全随机分为3组(每组30例):Ⅰ-gel喉罩组(Ⅰ组)、Supreme喉罩组(S组)、气管插管组(Q组).记录3组患者喉罩或插管置入时间、首次置入成功率,两个喉罩组侧卧位时的气道密封压、纤维支气管镜检查评分.记录入室后(T0)、插管前(T1)、插管即刻(T2)、拔管前(T3)、拔管即刻(T4)的生命体征.记录3组患者苏醒时间和拔管时间,术后呛咳、咽痛、恶心呕吐等副作用发生情况.结果 与Q组比较,Ⅰ组、S组置入时间缩短[(12±3)、(16±4)s比(30±6)s](P＜0.05),且Ⅰ组置入时间少于S组(P＜0.05);3组患者置入成功情况差异无统计学意义(P＞0.05);侧卧位时气道密封压Ⅰ组高于S组[(28±3) cmH2O比(24±4) cmH2O(1 cmH2O=0.098 kPa)](P＜0.05).Ⅰ组、S组在T2、T4时点MAP明显低于Q组[(86±10)、(85±9)mmHg(1 mmHg=0.133 kPa)比(105±11)mmHg,(91±11)、(92±12) mmHg比(106±14) mmHg](P＜0.05),HR明显慢于Q组[(75±9)、(76±11)次/min比(89±12)次/min,(83±9)、(82±11)次/min比(93±12)次/min] (P＜0.05).Ⅰ组、S组苏醒时间、拔管时间短于Q组[(2.5±1.4)、(2.8±1.2) min比(5.1±1.8) min,(3.8±1.1)、(3.7±1.0) min比(6.2±1.5) min] (P＜0.05).Ⅰ组、S组呛咳、咽痛发生率明显低于Q组[(0、0比33.3％)、(6.7％、16.7％比30.0％)](P＜0.05);其他副作用发生率差异无统计学意义(P＞0.05).结论 Ⅰ-gel喉罩、Supreme喉罩和气管导管均可安全有效地用于面神经显微血管减压术的气道管理,但Ⅰ-gel喉罩易于置入,气道密封性可靠,术中血流动力学平稳,损伤更小.