Paramedic King Laryngeal Tube Airway Insertion versus Endotracheal Intubation in Simulated Pediatric Respiratory Arrest

Abstract

Introduction: Pediatric endotracheal intubation (ETI) is difficult and can have serious adverse events when performed by paramedics in the prehospital setting. Paramedics may use the King Laryngeal Tube airway (KLT) in difficult adult airways, but only limited data describe their application in pediatric patients. Objective: To compare paramedic airway insertion speed and complications between KLT and ETI in a simulated model of pediatric respiratory arrest. Methods: This prospective, randomized trial included paramedics and senior paramedic students with limited prior KLT experience. We provided brief training on pediatric KLT insertion. Using a random allocation protocol, participants performed both ETI and KLT on a pediatric mannequin (6-month old size) in simulated respiratory arrest. The primary outcomes were 1) elapsed time to successful airway placement (seconds), and 2) proper airway positioning. We compared airway insertion performance between KLT and ETI using the Wilcoxon signed-ranks test. Subjects also indicated their preferred airway device. Results: The 25 subjects included 19 paramedics and 6 senior paramedic students. Two subjects had prior adult KLT experience. Airway insertion time was not statistically different between the KLT (median 27 secs) and ETI (median 31 secs) (p = 0.08). Esophageal intubation occurred in 2 of 25 (8%) ETI. Airway leak occurred in 3 of 25 (12%) KLT, but ventilation remained satisfactory. Eighty-four percent of the subjects preferred the KLT over ETI. Conclusions: Paramedics and paramedic students demonstrated similar airway insertion performance between KLT and ETI in simulated, pediatric respiratory arrest. Most subjects preferred KLT. KLT may provide a viable alternative to ETI in prehospital pediatric airway management.     

食管引流型喉罩和经典型喉罩的临床应用对比观察

目的比较经典型喉罩（CLMA）和食管引流型喉罩（PLMA）在骨科全麻手术中的应用,为临床安全有效选择喉罩提供参考依据。方法选择ASA分级Ⅰ～Ⅱ级,拟在全身麻醉下择期行骨科手术的患者100例,年龄18—60岁,体重指数（BMI）18-30kg／m2,随机分为CLMA组和PLMA组,每组50例。PLMA组沿食管引流孔插入14号胃管,观察两组喉罩一次置入成功率,尝试时间,头位,漏气率,胃胀气情况,记录患者入室,置入喉罩前,置入喉罩后以及离室四个时间点的平均动脉压,心率,血氧饱和度,并在术后2h,12～24h两个时间点随访患者是否咽喉痛,下颌痛,恶心呕吐,吞咽困难,声音嘶哑。结果两组患者的一般资料没有显著差异。喉罩置入时间,一次成功率,插罩方法,术中漏气需调整例数,以及通气失败需更换气管插管的例数,两组相比较均无显著差异（P〉0．05）,两组患者各时点生命体征组间比较差异无显著性（P〉0．05）。术中胃胀气以及插入喉罩时需调整头位为嗅花位的患者例数两组相比较,PLMA组明显低于CLMA组,有统计学差异（P〈0．05）,术后随访各并发症发生率均无统计学差异（P〉0．05）。结论与经典型喉罩相比较,食管引流型喉罩的机械通气效果和密封性更好,置入喉罩时简单伸展位即可顺利操作,成功率更高。     

The Intubating Laryngeal Mask Airway: Suggestions for Use in the Emergency Department

With the increased use of rapid-sequence induction and its potential complications, emergency physicians need a rescue device for unexpected difficult intubations. The intubating laryngeal mask airway (ILMA) is an ideal rescue airway since it can be placed quickly and can provide adequate ventilation in nearly all patients. It can then be used as conduit for endotracheal intubation, while ventilation is ongoing. The authors review the current literature on the ILMA. In conjunction with their experience using the ILMA in the emergency department (ED), a modification of the American Society of Anesthesiologists difficult airway algorithm was derived for use in the ED. The ILMA appears to be valuable for managing difficult airways.     

喉罩通气道与气管内插管在急救复苏中重建有效通气道的对比研究

目的检测喉罩通气道用于急救复苏中重建有效通气道的优越性.方法L组20例系各种因素导致呼吸衰竭或呼吸停止的患者,选择合适3～4型号的喉罩盲探插入正确位置,进行控制呼吸.E组20例手术麻醉患者,在静脉快诱导明视下行气管内插管机械通气,观察2组插管困难程度、插管成功次数、插管时间、插管后PetCO2波形、气道顺应性、SPO2、胸廓起伏状况、双肺呼吸音.结果L组盲探下插管全部1次成功,E组诱导明视下插管1次成功16例,3次以上4例.插管时间L组全部在30s内完成,E组在30s内完成16例,其余长达1min30s～3min20s(P＜0.05),相比差异有显著性.插管后两组气道顺应性,PetCO2、SPO2、双肺呼吸音判断导管位置均正确无误.结论应用喉罩通气道于急救复苏,与使用喉镜明视下快诱导行气管内插管相比,具有体位要求不高,操作简单,可盲探插管,为抢救此类患者赢得宝贵的抢救时间.     

Initial Experience of Emergency Physicians Using the Intubating Laryngeal Mask Airway: A Case Series

OBJECTIVE: Although the intubating laryngeal mask airway (ILMA) is widely available, its use by emergency physicians (EPs) has not been reported. The authors report the initial experience of EPs using the ILMA. A review of their experience and the relevant anesthesia literature provides a basis for EPs to use the ILMA more confidently and effectively. METHODS: Between January 2000 and January 2001, the ILMA was used on a convenience sample of emergency department (ED) patients undergoing "routine" intubations, and "rescue" situations, after failed rapid-sequence intubation (RSI). Patients were identified from the ED resuscitation case database. Chart review and intubating physician interviews focused on success of the device, complications encountered, and "pearls" of the device's use as perceived by the intubating physician. RESULTS: Ventilation with the appropriate-size ILMA occurred in less than 15 seconds in all "routine" intubations; tracheal intubation was subsequently accomplished in less than 1 minute. Eight of nine "routine" patients had blind tracheal intubation through the ILMA. One patient required fiberoptic bronchoscopy to guide the endotracheal tube into the trachea. Of the "rescue" intubations, all patients (n = 7) were successfully ventilated and five were successfully intubated using the ILMA. CONCLUSIONS: In this case series, the ILMA was easy to use in acute resuscitations, and proved to be invaluable in cases of failed RSI.     

Successful Tracheal Intubation through an Intubating Laryngeal Airway in Pediatric Patients with Airway Hemorrhage

Background

This case report describes the use of the air-Q intubating laryngeal airway (air-Q ILA; Cookgas LLC, St. Louis, MO) for airway rescue and a conduit for blind tracheal intubation in two pediatric patients with failed rapid sequence intubation and difficult airways secondary to airway bleeding in the emergency department (ED).

Objectives

To describe the use of a new supraglottic rescue device in the management of the pediatric patient’s difficult airway in the emergency setting.

Case Report

Case 1 was a 5-year-old boy who presented to the ED for bleeding one day after his tonsillectomy. After a rapid sequence intubation, direct laryngoscopy was difficult, with copious bleeding in the oropharynx and inability to visualize the glottis. After two failed direct laryngoscopic attempts to intubate, a size-2 air-Q ILA was inserted. A cuffed 5.0-mm inner diameter (ID) endotracheal tube (ETT) was blindly inserted through the lumen of the air-Q ILA into the trachea successfully. Case 2 was a 13-year-old boy who presented to the ED with a large nasopharyngeal laceration from a motor vehicle accident. After a rapid sequence intubation, direct laryngoscopy showed copious blood with no glottic visualization. A size 3 Laryngeal Mask Airway Classic™ (cLMA; LMA North America Inc., San Diego, CA) was inserted with a large airway leak, and blind ETT insertion via the cLMA was unsuccessful. Subsequently, a size-2.5 air-Q ILA was inserted and adequate ventilation was restored. A cuffed 6.0-mm ID ETT was blindly inserted through the air-Q ILA into the trachea successfully.

Conclusion

Two cases of failed laryngoscopy in pediatric patients with blood in the airway are described. In each case, insertion of an air-Q ILA was followed by successful blind tracheal intubation via the lumen of the air-Q ILA.     

喉罩通气在院前心肺复苏中的临床研究

目的:探讨院前心肺复苏(CPR)时早期盲插喉罩通气对复苏成功率的影响。方法:对院前发生心跳呼吸骤停患者460例,根据CPR时对患者建立人工气道的不同措施将其分为3组,A组210例,常规CPR时即盲插喉罩通气;B组40例,常规CPR时即行气管内插管;C组210例,常规CPR时以球囊面罩装置通气,转送至急诊科再行气管内插管,插管延迟时间5～15min。结果:插管所需时间:A组10.4±7.5s;B组96±25.7s;C组52±27.5s;3组相比差异有显著性(P<0.001)。一次插管成功率:A组盲探下插入喉罩全部1次成功,成功率100%;B组插管1次成功28例,2次成功9例,3次以上3例,一次插管成功率70%;C组插管1次成功200例,2次成功10例,一次插管成功率95.2%;3组相比差异有显著性(P<0.01)。复苏成功率:A组复苏成功41例,成功率19.5%;B组复苏成功1例,成功率2.5.%;C组复苏成功8例,成功率3.8%;A组与B、C组复苏成功率比较差异有显著性(P<0.01),B组与C组复苏成功率比较差异无显著性(P>0.05)。结论:在院前心肺复苏时,早期盲插喉罩通气具有操作快捷,可盲探插管且成功率高,能明显提高抢救成功率,而早期气管插管需时长,一次插管成功率较低,不能提高CPR成功率。     

喉罩在临床麻醉中的应用

目的观察喉罩全身麻醉的通气功能。方法择期全身麻醉手术患者100例,ASAⅠ-Ⅱ级,按随机数字表法分为：喉罩组（LM组）和气管插管组（TI组）,每组50例。全身麻醉诱导后,2组患者分别插入喉罩和气管插管,麻醉机控制呼吸。丙泊酚微量泵输入,监护仪监测麻醉诱导前,插管后1、5、10 min,拔管前,拔管后1、5、10 min,各时点生命体征数值,并在插管后30 min行血气分析。结果 2组患者各时点生命体征比较,气管插管后1、5、10 min TI组SBP高于LM组（P〈0.01或P〈0.05）。插管后1、5 min TI组DBP高于LM组（P〈0.05）,气管插管后1 min TI组HR高于LM组（P〈0.01）。2组患者插管后30 min时点监护仪数值与血气分析比较差异无统计学意义（P〉0.05）。结论喉罩机械通气效果良好,在监护仪的有效监测下全身麻醉应用是安全的。     

Effectiveness of Prehospital Continuous Positive Airway Pressure in the Management of Acute Pulmonary Edema

Objective. To compare the effectiveness of continuous positive airway pressure (CPAP) with standard pharmacologic treatment in the management of prehospital acute pulmonary edema. Methods. Using a nonrandomized control group design, all consecutive patients presenting to two participating emergency medical services (EMS) systems with a field impression of acute pulmonary edema between July 1, 2004, andJune 30, 2005, were included in the study. The control EMS system patients received standard treatment with oxygen, nitrates, furosemide, morphine, and, if indicated, endotracheal intubation. The intervention EMS system patients received CPAP via face mask at 10 cm H₂O in addition to standard therapy. Results. Ninety-five patients received standard therapy, and120 patients received CPAP andstandard therapy. Intubation was required in 8.9% of CPAP-treated patients compared with 25.3% in the control group (p = 0.003), andmortality was lower in the CPAP group than in the control group (5.4% vs. 23.2%; p = 0.000). When compared with the control group, the CPAP group had more improvement in respiratory rate (?4.55 vs. ?1.81; p = 0.001), pulse rate (?4.77 vs. 0.82; p = 0.013), anddyspnea score (?2.11 vs. ?1.36; p = 0.008). Using logistic regression to control for potential confounders, patients receiving standard treatment were more likely to be intubated (odds ratio, 4.04; 95% confidence interval, 1.64 to 9.95) andmore likely to die (odds ratio, 7.48; 95% confidence interval, 1.96 to 28.54) than those receiving standard therapy andCPAP. Conclusion. The prehospital use of CPAP is feasible, may avert the need for endotracheal intubation, andmay reduce short-term mortality.     

Feasibility of Out-of-Hospital Cardiac Arrest Ultrasound by EMS Physicians

Introduction: Point-of-care ultrasound (POCUS) has been suggested as a useful tool to predict survival and guide interventions in out-of-hospital cardiac arrest (OHCA). While POCUS has been deployed in prehospital settings, a minimal amount of data exists on prehospital use, particularly by personnel with limited ultrasound experience. We aimed to characterize the feasibility and barriers to prehospital POCUS during OHCA by emergency medicine services (EMS) physicians in training. Methods: We deployed the SonoSite iViz portable ultrasound device for use by EMS physicians for OHCA in an urban EMS system. All physicians received POCUS education as part of their graduate medical training and were provided an instructional video on use of the SonoSite iViz device. POCUS use was limited to identifying cardiac motion during pulse checks, without interrupting resuscitation, and the results could be used to supplement management at the physicians’ discretion. Data were recorded prospectively by saving images on the device and through a custom electronic form within the patient care report. The primary measure was the frequency of use of POCUS during OHCA. Secondarily, we characterized agreement by expert (ultrasound fellowship trained) faculty (using a kappa statistic) and identified reported barriers to the use of prehospital POCUS. Results: From November 2016 to March 2017, 348 physician field responses were reviewed, including 127 cases of OHCA. There were 106 patients remaining in arrest on physician arrival, with 56 (52.8%) cases of POCUS use. Still or video images were recorded in 48 cases; video in 34 cases. From video images, agreement in identifying cardiac motion between the EMS physician and expert reviewer occurred in 91% of cases (K?=?0.82). Reasons cited for not using POCUS included return of circulation soon before or after arrival, prioritizing clinical interventions, not having the ultrasound device, mechanical failure, and cessation of resuscitation per advanced directives. Conclusion: Use of POCUS by EMS physicians to detect cardiac activity in OHCA is feasible and correlates with expert interpretation. Several avoidable barriers were identified and should be considered in the future implementation of prehospital POCUS. Larger studies are needed to determine what role POCUS may play in prehospital cardiac arrest management.     

Probabilistic Linkage of Prehospital and Outcomes Data in Out-of-hospital Cardiac Arrest

Abstract

Objective. Lack of longitudinal patient outcome data is an important barrier in emergency medical services (EMS) research. We aimed to demonstrate the feasibility of linking prehospital data from the California EMS Information Systems (CEMSIS) database to outcomes data from the California Office of Statewide Health Planning and Development (OSHPD) database for patients with out-of-hospital cardiac arrest (OHCA). Methods. We included patients age 18 years or older who sustained nontraumatic OHCA and were included in the 2010–2011 CEMSIS databases. The CEMSIS database is a unified EMS data collection system for California. The OSHPD database is a comprehensive data collection system for patient-level inpatient and emergency department encounters in California. OHCA patients were identified in the CEMSIS database using cardiac rhythm, procedures, medications, and provider impression. Probabilistic linkage blocks were created using in-hospital death or one of the following primary or secondary diagnoses (ICD-9-CM) in the OSHPD databases: cardiac arrest (427.5), sudden death (798), ventricular tachycardia (427.1), ventricular fibrillation (427.4), and acute myocardial infarction (410.xx). Blocking variables included incident date, gender, date of birth, age, and/or destination facility. Due to the volume of cases, match thresholds were established based on clerical record review for each block individually. Match variables included incident date, destination facility, date of birth, sex, race, and ethnicity. Results. Of the 14,603 cases of OHCA we identified in CEMSIS, 91 (0.6%) duplicate records were excluded. Overall, 46% of the data used in the linkage algorithm were missing in CEMSIS. We linked 4,961/14,512 (34.2%) records. Linkage rates varied significantly by local EMS agency, ranging from 1.4 to 61.1% (OR for linkage 0.009–0.76; p < 0.0001). After excluding the local EMS agency with the outlying low linkage rate, we linked 4,934/12,596 (39.2%) records. Conclusion. Probabilistic linkage of CEMSIS prehospital data with OSHPD outcomes data was severely limited by the completeness of the EMS data. States and EMS agencies should aim to overcome data limitations so that more effective linkages are possible.     

丙泊酚联合芬太尼、瑞芬太尼用于可弯曲喉罩置管效果的观察与评价

目的:探讨丙泊酚联合芬太尼或瑞芬太尼在功能性鼻内窥镜手术中可弯曲喉罩置管的效果.方法:择期行功能性鼻内窥镜手术(FESS术)患者54例,随机分为芬太尼组(F组)和瑞芬太尼组(R组)各27例,分别静脉注射芬太尼1μg/kg或瑞芬太尼0.5 μg/kg,30 s后注射丙泊酚2.5 mg/kg.结果:两组"下颌松弛度"和"窒息时间'无统计学差异,R组"咳嗽与体动反射"低于F组,F组"首次置管成功率"高于R组,R组"口咽部结构"优于F组.结论:功能性鼻内窥镜手术中丙泊酚联合芬太尼或瑞芬太尼均能为可弯曲喉罩提供良好的置管条件,为手术提供有效、安全的通气,术后不良反应和合并症少.     

帕瑞昔布与氟比洛芬酯预防喉罩全麻术后不良反应的观察

目的对比研究帕瑞昔布和氟比洛芬酯预防喉罩全麻术后咽痛、躁动等不良反应。方法采用双盲、随机对照试验设计。选择76例骨科择期手术患者,随机分为3组,A组为对照组,患者25例,于诱导前给予生理盐水5mL静推;B组患者27例,于诱导前氟比洛芬酯1mg·kg-1静推;C组患者24例,于诱导前帕瑞昔布40mg静推。比较各组间上述时间点（T0、T1、T2）的MAP、HR波动情况及术后咽痛、躁动等不良反应的发生情况。结果各组间患者年龄、性别、体重、麻醉时间、舒芬太尼用量等差异均无统计学意义（P〉0．05）。在插管期,B组、C组的MAP、HR波动明显低于A组（P〈0．05）;在拔管期,B组与C组的血流动力学波动及减少术后咽痛的发生明显优于A组（P〈0．05）,但C组血流动力学及术后咽痛不良反应发生明显低于B组（P〈0．05）。结论诱导前静注帕瑞昔布40mg有利于喉罩全麻手术患者插管与拔管期血流动力学平稳,并可有效预防术后咽痛等不良反应的发生。     

双管喉罩与气管插管用于全麻妇科腹腔镜手术的效果比较

目的探讨双管喉罩与气管插管用于全身麻醉妇科腹腔镜手术的安全性和可行性。方法 2009年1月5月择期妇科腹腔镜手术患者60例,ASAⅠ～Ⅱ级,随机分为喉罩组（P组）和气管插管组（T组）。记录入室基础值（T0）,置罩（管）前（T1）,置罩（管）后即刻（T2）,置罩（管）后5min（T3）,拔除罩（管）即刻（T4）,拔除罩（管）后5min（T5）的收缩压（systolic pressure,SBP）,舒张压（diastolic pressure,DBP）,心率（heart rate,HR）和脉搏血氧饱和度（pulse oxygen saturation,SpO2）,喉罩和气管插管控制呼吸时气腹前后不同时段的气道峰压（airway.maximum pressure,Pmax）,潮气量（vital volume,VT）和呼气末二氧化碳分压（endtidal CO2,PETCO2）。记录插罩（管）成功率,及相关并发症。结果 T2时T组SBP,DBP和HR显著高于P组（P〈0.05）,两组术中通气均满意;Pmax,VT和PETCO2组间比较各时点无差异（P〉0.05）。气腹后Pmax和PETCO2组内比较均高于气腹前,差异有统计学意义（P〈0.05）。置罩（管）成功率组间比较差异无统计学意义,拔罩（管）期及术后24h并发症,喉罩组明显低于气管导管组,差异显著（P〈0.05）。结论双管喉罩用于全麻妇科腹腔镜手术通气效果满意,安全可行。     

食管引流型喉罩与气管插管在重度窒息新生儿复苏中的对比研究

目的：观察食管引流型喉罩（PLMA）对重度窒息新生儿复苏的可行性、有效性和安全性,比较PLMA与气管插管在重度窒息新生儿复苏中的临床效果。方法：将我院171例重度窒息新生儿随机分为观察组96例和对照组75例,分别应用PLMA和气管插管进行复苏,比较两种方法的复苏效果。结果：观察组PLMA插入时间、起效时间、气道损伤发生率及一次性成功率均明显优于对照组（P〈0．05）;两组复苏1min、5min时的SpO2、Apgar评分、PaO2、PaCO2及pH值均明显优于复苏前（P〈0．05）,但两组间同一时间点无明显差异（P〉0．05）。结论：食管引流型喉罩在重度窒息新生儿复苏中有较好的临床效果,操作简单,且气道损伤率低,建议临床推广应用。     

King Airway Use by Air Medical Providers

Background. In cases of difficult or failed endotracheal intubation (ETI), alternate airways are designed to provide adequate oxygenation andventilation until a definitive airway can be established. The King Laryngeal Tube Disposable (LTD) is a new superglottic alternate airway. Objective. To describe the use, rates of success, andoutcomes of the King airway by highly skilled prehospital providers. Method. In this retrospective analysis, we examined prehospital King airway use by a large regional air medical service for the period from March 2006 to December 2006. Rescuers used alternate airways after three unsuccessful ETI attempts or in situations of anticipated ETI difficulty. We identified clinical characteristics, described airway difficulties, anddetermined the success of airway placement. Where available, we evaluated the hospital course andoutcomes. Results. Of 575 ETI, alternate airways were used in 27 cases, including 26 King airway placements (4.5%, 95% CI: 3.0–6.6%). All were successfully placed; 24 required one attempt, andtwo required more than one attempt. No immediate complications were observed. No prehospital surgical airways were performed. Follow-up data were available for 15 of 26 patients. Five patients were in cardiac arrest anddid not survive to hospital admission. Many of the patients required specialized efforts from anesthesia or surgery for definitive airway management with 40% (4/10) requiring emergent tracheostomy. Conclusion. In this series of critically ill patients, air medical providers successfully used the King airway as an alternate airway device. Definitive airway management was complicated andrequired specialized efforts from surgery andanesthesia.     

Feasibility of Continuous Positive Airway Pressure by Primary Care Paramedics

Abstract

Introduction. Continuous positive airway pressure (CPAP) has been used effectively in the prehospital environment for a wide range of respiratory emergencies. The feasibility of CPAP when used by primary care paramedics (PCPs) has not been established. Objective. We sought to study the feasibility of prehospital CPAP when used by paramedics trained to the primary care paramedic (PCP) level compared with those trained to the advanced care paramedic (ACP) level. Our hypothesis was that the feasibility of CPAP use by paramedics trained to the PCP level is similar to that of paramedics trained to the ACP level. Methods. We conducted an observational study of 302 consecutive cases of CPAP use over one year beginning June 25, 2009. We defined compliant use as 100% adherence to the provincial CPAP medical directive. The criteria for compliance included specifics of patient presentation, vital signs, and appropriate documentation by the paramedic, as well as proper use, titration, and discontinuation of CPAP equipment according to protocol. Data were abstracted from ambulance call reports. Results. Using the criteria set out for compliant CPAP use, the highest level of compliance among the ACPs and the PCPs was 98.6% and 98.9%, respectively, for documenting indication for CPAP use. The lowest level of compliance among the ACPs was 84.4% for titration of CPAP during treatment, and the lowest level of compliance among the PCPs was 90% for adherence to criteria for CPAP application according to patients’ vital signs. Overall, the criteria for compliant use of CPAP were met for 76.8% (232/302) of the call reports examined. The rate of compliant use of CPAP was 75.9% (161/212) for ACP calls and 78.9% (71/90) for PCP calls. The difference between rates of compliant use for ACP calls versus PCP calls was not statistically significant (χ² [1 df] = 0.31, p = 0.66). Conclusions. This study found no significant difference in the compliant use of prehospital CPAP between paramedics trained to the PCP level and those trained to the ACP level. This study suggests that CPAP use by PCP-level paramedics may be feasible. Further study is required to determine whether compliance translates to safe use of prehospital CPAP by PCP-level paramedics.