Mask lung ventilation by ambulance personnel: a performance assessment

We evaluated the ability of basic life support ambulance officers and anaesthetists to perform lung ventilation with a face mask. After induction of anaesthesia and institution of standardized airway conditions the ambulance officer or anaesthetist placed a mask on the patient’s face and lung ventilation was commenced. The order of hand grip (one vs two hands) was randomized. The mask was connected to a ventilator which had flow and pressure transducers in the inspiratory and expiratory breathing circuits. The output of these devices was sent to an electronic integrator to determine volumes. Calibration of the flow transducers was made against a spirometer while ventilating a test lung. Oesophageal insufflation was determined by listening over the epigastrium with a stethoscope. Data collected included presence of gastro-oesophageal insufflation, inspiratory and expiratory volumes. Expiratory volumes for ambulance officers and anaesthetists at 30 cm H₂O were greater than that of ambulance officers at 20 cm H₂O (P < 0.001) but profession of the mask holder or hand grip had no effect on expiratory volume. There was no difference in the mask leak when the professions were compared but ambulance officers had a lower mask leak with a two-handed grip at 20 cm H₂O (P < 0.001). Anaesthetists had a greater incidence of gastro-oesophageal insufflation when a two-handed mask grip was utilized (P < 0.05). In healthy relaxed patients there appeared to be little difference between the ambulance officers and qualified anaesthetists in airway maintenance or mask-holding ability.     

喉罩用于甲亢患者甲状腺手术全身麻醉的临床观察

目的 观察甲亢患者甲状腺次全切除术中应用喉罩通气行全身麻醉对血液动力学的影响。方法 40例甲亢甲状腺次全切除术患者,随机分为气管插管组（T组）与喉罩置入组（L组）,每组20例。气管插管用喉镜明视插入法,喉罩按顺行盲探置入口底。全部患者均于麻醉诱导后插管（或罩入喉罩）前（T0）、气管插管（或罩入）后即刻（T1）、1 m in（T2）、3 m in（T3）、5 m in（T4）各时间点监测SBP、MAP、HR值。术后24 h随访记录患者咽痛、声嘶的发生率。结果 L组在置入喉罩前后各时点SBP、MAP、HR无显著性变化（P〉0.05）,T组在插管后各时点与T0相比SBP、MAP、HR均明显升高（P〈0.05）。T组T1、T2、T3各时点SBP、MAP、HR均高于L组（P〈0.05）。术后24 h咽痛、声嘶副作用发生率,T组明显高于L组（P〈0.05）。结论 喉罩对血流动力学影响小、安全性高、副作用用少,比气管插管更适合于甲亢患者甲状腺手术的全麻要求。     

超声引导下肢神经阻滞联合喉罩下全麻用于全膝关节置换术的效果

目的 评价超声引导下肢神经阻滞联合喉罩下全麻用于全膝关节置换术的效果.方法 择期行全膝关节置换术的病人加例,性别不限,年龄52～80岁,体重67～94 kg,ASA分级Ⅰ～Ⅲ级,采用随机数字表法,将其随机分为2组(n=20).Ⅰ组在气管插管下行静吸复合全麻;Ⅱ组先在超声引导下行下肢神经阻滞,然后在喉罩下行静吸复合全麻.术中和麻醉恢复室(PACU)停留期间维持HR 50～100次/min,维持MAP波动幅度不超过基础值的20%.必要时给予血管活性药物(阿托品、艾司洛尔、麻黄碱、乌拉地尔或拉贝洛尔).术后采用曲马多和氯诺昔康行PCIA(背景输注速率2 ml/h,PCA量1 ml,锁定时间15 min),维持VAS评分≤2分.记录术中和PACU停留期间血管活性药物的使用情况;记录PACU停留时间;记录术后24 h内PCA药物用量和恶心呕吐的发生情况.结果 与Ⅰ组比较,Ⅱ组术中各血管活性药物的使用率降低,PACU停留期间艾司洛尔、乌拉地尔和拉贝洛尔的使用率降低,PACU停留时间缩短,PCA药物用量减少,术后恶心呕吐发生率降低(P<0.01).结论 超声引导下肢神经阻滞联合喉罩下全麻用于全膝关节置换术麻醉效果较好,并发症少,术后镇痛药物用量少,优于气管插管下全麻.

Abstract：

Objective To evaluate the efficacy of uhrasound-guided lower extremity nerve block combined with general anesthesia with laryngeal mask airway in patients undergoing total knee arthroplasty.Methods Forty ASA Ⅰ-Ⅲ patients of both sexes,aged 52-80 yr,weighing 67-94 kg,undergoing total knee arthroplasty under general anesthesia,were randomly divided into 2 groups(n=20 each).Group Ⅰ received combined intravenous-inhalational anesthesia with endotracheal tube.Group Ⅱ received lower extremity nerve block guided by ultrasound and then combined intravenous-inhalational anesthesia with laryngeal mask airway.HR was maintained at 50-100bpm,MAP was maintained at the preoperative baseline level(increase or decrease amplitude<20%of the baseline level)during operation and in pestanesthesia care unit(PACU)and vasoaetive drugs(atropine,esmolol,efedrina,urapidil or labetalol)were given when necessary.The patients received patient-controlled intravenous analgesia with tramedol and lornoxicam(background infusion 2 ml/h,bolus dose 1 ml,lockout interval 15 min)after operation and VAS score was maintained at≤2.The requirement for vasoactive drugs during operation and in PACU,PACU stay length,and consumption of analgesics and occurrence of nausea and vomiting within 24 h after operation were recorded.Results Compared with group Ⅰ,the requirement for all vasoaetive drugs during operation and for esmolol,urapidil and labetalol in PACU was significantly reduced,PACU stay length Was significantly shortened,and the consumption of analgesics and incidence of nausea and vomiting were significantly reduced in group Ⅱ(P<0.01).Conclusion Ultrasound-guided lower extremity nerve block combined with general anesthesia with laryngeal mask airway provides better emcacy with fewer complications and less consumption of postoperative analgesics than general anesthesia with endotracheal tube in patients undergoing total knee arthroplasty.     

腹腔镜手术患者CLMA喉罩、SLIPA喉罩与PLMA喉罩气道管理的效果

目的 比较经典型喉罩(CLMA喉罩)、SLIPA喉罩和食管引流型喉罩(PLMA喉罩)用于腹腔镜手术患者气道管理的效果.方法 择期行腹腔镜手术患者123例,年龄20～64岁,ASA分级Ⅰ或Ⅱ级,随机分为3组:CLMA组(C组,n=41)、SLIPA组(S组,n=42)和PLMA组(P组,n=40).麻醉诱导后置入喉罩,行间歇正压通气.测定气道密封压后实施气腹.评估喉罩置入难易性.记录首次喉罩置入情况、喉罩置入时间、麻醉恢复时间和不良反应的发生情况.于气腹前及气腹压至12 mm Hg时记录气道吸气峰压(PIP)及气道密封压＜PIP的发生情况.结果 C组有1例患者更换喉罩型号后置入成功,其余患者均首次喉罩置入成功,组间比较差异无统计学意义(P＞0.05).与C组比较,S组喉罩置入时间和麻醉恢复时间缩短,喉罩置入容易,P组喉罩置入时间延长,气道密封压升高,气道密封压＜PIP的患者减少(P＜0.05).与S组比较,P组喉罩置入时间和麻醉恢复时间延长,喉罩置入稍难,气道密封压升高,气道密封压＜PIP的患者减少(P＜0.05).与气腹前比较,各组气腹至12 mm Hg时PIP升高(P＜0.05).三组患者不良反应发生率比较差异无统计学意义(P＞0.05).结论 CLMA喉罩、SLIPA喉罩和PLMA喉罩均可保证有效通气,不良反应少.SLIPA喉罩置入更简单,而PLMA喉罩气道密封效果好,更适用于腹腔镜手术患者.     

低套囊压力下ProSeal或Supreme喉罩用于腹腔镜手术患者气道管理的效果

目的 评价低套囊压力下ProSeal和Supreme喉罩用于腹腔镜手术患者气道管理的效果.方法 择期仰卧位腹腔镜手术患者60例,ASA分级Ⅰ或Ⅱ级,年龄20～70岁,体重50～80 kg,随机分为ProSeal喉罩组(P组)和Supreme喉罩组(S组),每组30例.喉罩置入成功后,用手持测压计监测套囊充气压力并维持其为35 cm H2O,记录气道密闭压及气腹前后机械通气时气道压峰值和平均气道压,记录术后并发症的发生情况.结果 两组气腹后机械通气时气道压峰值高于气腹前(P＜0.05),两组间比较差异无统计学意义(P＞0.05);术中气腹前后均无漏气现象发生;两组气道密闭压比较差异无统计学意义(P＞0.05);两组拔除喉罩后表面带有血丝及术后咽痛发生率比较差异无统计学意义(P＞0.05).结论低套囊压力(35 cm H2O)下ProSeal和Supreme喉罩通气效果均较好,可安全地用于腹腔镜手术患者的气道管理.     

食管引流型喉罩间歇正压通气时头前屈位对气道密封压的影响

Objective To evaluate the influence of head anteflexion on airway sealing pressure during intermittent positive pressure ventilation(IPPV) with ProSeal laryngeal mask airway (PLMA) with an esophageal vent.Methods Fifty ASA Ⅰ or Ⅱ patients (20 males and 30 females), aged 18-51 ye are, weighing 50-70 kg and scheduled for elective plastic surgery under general anesthesia, were enrolled in this study. Anesthesia was induced with fentanyl 2 μg/kg, propofol 2 μg/kg and vecuromium 0.1 mg/kg. PLMA with an esophageal vent was inserted at 2 min after intravenous vecuronium injection.The airway sealing pressure, the anatomic position of the cuff and the efficacy of positive pressure ventilation were checked in the neutral and anteflexed head positions with the cuff deflated and inflated to an intracuff pressure of 60 cm H2 O, respectively.Results The lungs were better ventilated in the head anteflexion position than in the head neutral position whether the cuff was deflated or inflated. There was no significant difference in the volume of air required to achieve an intracuff pressure of 60 cm H2O between the two head positions ( P＞ 0.05). The airway seating pressure increased from (27 ± 6) cm H2O in the head neutral position to (33 ± 6) cm H2O in the head anteflexion position, with no significant difference between them ( P＞ 0.05). The expired tidal volume and the peak inspiratory pressure during IPPV were (496 ± 81 ) ml and (14.3 ± 1.9) cm H2O respectively in the head neutral position and (496 ± 81 ) ml and ( 14.5 ± 2.1 )cm H2O respectively in the head anteflexion position.Conclusion Head anteflexion can significantly improve airway sealing but does not affect the anatomic position of the cuff.Appropriate head anteflexion is a simple and effective way to improve IPPV when the airway sealing pressure is inadequate in the head neutral position.     

AuraFlex喉罩在老年患者脊柱外科手术中的应用

目的观察AuraFlex喉罩在老年患者脊柱外科手术中应用的安全性和有效性。方法选择择期全麻下脊柱外科俯卧位手术的老年患者127例,男74例,女53例,年龄65~79岁,体重45~90kg,BMI 18.5~25.0kg/m2,ASAⅡ或Ⅲ级,随机分为两组:喉罩组(L组)和气管导管组(T组),全麻诱导后分别置入AuraFlex喉罩(L组)或钢丝加强型气管导管(T组)。记录诱导开始前(T0)、人工气道置入前(T1)、置入后1min(T2)、置入后3 min(T3)、拔除前(T4)、拔除后1 min(T5)、拔除后3min(T6)的HR、SBP、DBP。记录置入时间、置入次数。记录平卧位改俯卧位前后气道峰压(Ppeak)、喉罩气道密封压(PAS)和纤维支气管镜检查分级(FBS)。记录手术开始时、手术开始后1h、手术开始后2h和手术结束时Ppeak和PAS。记录拔管前FBS。记录拔除人工气道时至拔除后30min内,有无低氧血症(SpO290%)、喉痉挛、呛咳、呕吐、咽喉痛,人工气道的套囊或管壁内外有无血迹和污物。结果与T0时比较,T2、T3、T5时T组HR明显增快、SBP和DBP明显升高(P0.05或P0.01),且明显高于L组(P0.05或P0.01)。两组组内组间不同时点Ppeak和纤维支气管镜分级差异均无统计学意义。人工气道拔出时和拔出后30min内,L组的呛咳、咽喉痛发生率和低氧血症、声音嘶哑发生率明显低于T组(P0.05或P0.01)。结论在选择好适应证和加强监测的前提下,相较于钢丝加强气管导管,应用AuraFlex喉罩围术期循环更稳定,术后呼吸道并发症更少,可以安全有效地用于老年患者脊柱外科手术。     

不同头颈位置时i-gel喉罩对全麻手术患者气道密封压和通气效果的影响

目的 探讨不同头颈位置时i-gel喉罩对全麻手术患者气道密封压(OLP)和通气效果的影响.方法 择期全麻手术患者30例,性别不限,年龄32 ～ 64岁,BMI 18 ～ 30 kg/m2,ASA分级Ⅰ或Ⅱ级.麻醉诱导后,采用单手旋转盲插法置人i-gel喉罩,置入成功后行机械通气.分别在头颈正中位、俯屈位、仰伸位及侧旋位(右侧)时记录OLP、呼出潮气量(VTE)、气道峰压(PPeak)和通气效果,并采用纤维支气管镜观察咽部解剖结构显露情况.结果 与头颈正中位比较,头颈俯屈位时OLP和PPeak升高,VTE降低,头颈仰伸位时OLP和PPeak降低,VTE升高,头颈俯屈位时通气效果较差(P＜0.05),不同头颈位置时咽部解剖结构显露程度差异无统计学意义(P＞0.05).结论 i-gel喉罩用于全麻手术患者时应避免头颈俯屈位.     

Assessment of dry eye disease in N95 versus surgical face mask wearers during COVID-19

Purpose:Investigating the effect of different face masks on dry eye disease (DED) among healthcare workers during the COVID-19 pandemic.Methods:This was a comparative, cross-sectional study. Participants were included into two groups: group 1 (n = 30) wore surgical masks, and group 2 (n = 30) wore N95 masks with face shields. Demographic and ocular surface disease index questionnaires (OSDI) were performed. In addition, Tear break-up time (TBUT), corneal and conjunctival fluorescein staining, and meibography to assess meibomian gland loss (MGL) were performed on all participants. Independent T-test was used to compare continuous parameters and Chi-square test for categorical variables. The relationship between continuous variables was tested using bivariate Pearson correlation.Results:Sixty healthcare workers participated in this study (36 females and 24 males). The mean (±SD) age of the surgical mask and N95 groups was 35.33 (±14.94) and 36.63 (±10.64) years, respectively. Both masks caused dryness according to TBUT, MGL, and OSDI scores. DED per DEWS II definition was observed in 14 (46.7%) and 16 (53.3%) patients in groups 1 and 2, respectively. Comparing the two groups, N95 mask caused significantly more dryness according to TBUT (P = 0.042) and fluorescein staining (P = 0.038 for the right eye and P = 0.015 for the left eye).Conclusion:Physicians should be aware of the potential dry eye signs secondary to face mask wear during the COVID-19 pandemic. Further attention should be taken in patients who suffer from preexisting dry eye syndrome and in patients who undergo intraocular operations.