Introduction
Prehospital medical care is a critical component of health care services. Reference Mehmood, Rowther, Kobusingye and Hyder1 Delivering early care at the site of emergency has an important resuscitation role in reducing mortality, morbidity, and disabilities. Reference Aziz, Lee and Escobedo2 In the case of pediatric emergencies, effective airway management is important, as cardiac arrest in children is frequently linked to hypoxia. Reference Vega, Kaur, Sasaki and Edemekong3 Pediatric out-of-hospital cardiac arrest results in a 12% mortality rate and leads to unfavorable neurological outcomes. Reference Okubo, Komukai and Izawa4 Severe traumatic injuries are a common source of mortality; often, endotracheal intubation (ETI) is important to enhance oxygen levels and prevent the risk of aspiration. Reference Orso, Vetrugno, Federici, D’Andrea and Bove5 The expeditious intubation out of the hospital by paramedics significantly enhances the survival rate by maintaining a patent airway, ensuring effective ventilation, and preventing aspiration. Reference Crewdson, Lockey, Voelckel, Temesvari, Lossius and Medical Working Group6
Paramedics equipped with advanced training and intubation experience have shown high success rates (ranging from 84%-95%) in adults. Reference Delorenzo, St Clair, Andrew, Bernard and Smith7–Reference Burns, Habig, Eason and Ware9 The anatomical and physiological characteristics of pediatric patients, combined with the specific challenges in emergencies, increase the complexity of ETI and raise the risk of failure and complications. Reference Harless, Ramaiah and Bhananker10 However, pediatric cases represent only approximately 8.9%-13.0% of emergencies, Reference Meckler, Hansen and Lambert11 and only 0.1%-5.0% required ETI. Reference Garner, Bennett, Weatherall and Lee12 Pediatric patients who present at the hospital with no detectable pulse and apnea exhibit a lower survival rate, in addition to neurological impairment in survival cases. Reference Zwingmann, Mehlhorn, Hammer, Bayer, Südkamp and Strohm13 Pediatric tolerance to apnea is less efficient than adult, due to high oxygen demand and low oxygen reserves. Reference Akbudak, Mete and Erbay14
While many Emergency Medical Services consider pediatric intubation as an essential paramedic skill, there is notable divergence in the utilization of this skill across the United States. Reference Mahtani, Eaton, Catterall and Ridley15 The specialized training in procedural and decision-making competencies establish and elevate quality standards in the paramedics outside of a hospital setting. Reference Dowling16 Pediatric intubation has been conducted without the use of muscle relaxants, but there is a current trend among several protocols to use muscle relaxants during intubation, which may enhance overall success rates. Reference Garner, Bennett, Weatherall and Lee17
This meta-analysis aims to systematically review and synthesize the available literature to assess the knowledge, confidence, and attitude of paramedics through overall success rate and associated complications.
Methods
The study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Reference Hutton, Salanti and Caldwell18 and Cochrane guidelines. 19
Literature Search Strategy
Databases searched were PubMed (National Center for Biotechnology Information, National Institutes of Health; Bethesda, Maryland USA); SCOPUS (Elsevier; Amsterdam, Netherlands); Cochrane (Wiley; Hoboken, New Jersey USA); and Web of Science (Clarivate Analytics; London, United Kingdom) for relevant articles reporting the paramedic’s pediatric intubation, success rate, and complications using the following keywords: (“Airway Management” OR Intubation OR Prehospital OR Airway OR “out-of-hospital”) AND (Pediatrics OR Child) AND (Paramedics OR EMS); Figure 1.
Figure 1. PRISMA Illustrating the Study Selection Process.
Abbreviation: PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.
Eligibility Criteria and Study Selection
In the study, all study designs were included reporting the paramedic’s pediatric intubation and assessing the success rate or complications. Non-English studies, conference abstracts, reviews, and studies without eligible data were excluded. The selection procedure involved two separate sets of authors, and in case of disagreements, a third author was consulted for resolution.
Assessing the Risk of Bias
The Newcastle-Ottawa Scale (NOS) was employed to evaluate the quality of cohort studies, considering domains related to selection, comparability, and exposure, with each domain receiving a star rating, up to a maximum of nine stars. 20 Additionally, for the assessment of potential bias in the included clinical trials, the Cochrane risk of bias was used and studies were assigned a judgment of low, high, or unclear risk of bias. Reference Higgins, Altman and Gøtzsche21 Two independent authors conducted the quality assessment of the studies, and with any disagreements, a third author was consulted for resolution.
Data Extraction
Data were extracted in an Excel (Microsoft Corp.; Redmond, Washington USA) sheet on the following: (1) study characteristics including study ID, study setting, study design, total pediatric population, inclusion criteria, and gender; and (2) outcomes including overall intubation success rate, first attempt success rate, overall complication, esophageal intubation, aspiration, and three or more intubation attempts.
Statistical Analysis
A meta-analysis was conducted to report point estimates and the confidence interval (CI) using open meta-analyst software. Data were pooled as risk ratio (RR) and 95% confidence interval. The meta-analysis was performed using a random effects model because of heterogeneity in the eligible studies that were synthesized. The heterogeneity of individual studies was evaluated using the I-square (I2); data were considered heterogeneous with chi-square P < .1.
Results
Literature Search
Based on the systemic search, 1,525 records were retrieved, and 416 duplicates were removed. A total of 1,109 records were screened by title and abstract screening and 1,053 were excluded. Fifty-six studies were suitable for full-text screening, and 38 were finally included according to the eligibility criteria Reference Garner, Bennett, Weatherall and Lee12,Reference Vilke, Steen, Smith and Chan22–Reference Aijian, Tsai, Knopp and Kallsen58 (PRISMA Flow Diagram; Figure 1).
Characteristics of the Included Studies
This systematic review included 38 studies; 33 were retrospective cohorts, three were prospective cohorts, one was a clinical trial, and one was a case-control. The summary of characteristics is summarized in Table 1.
Table 1. Study Characteristics
Abbreviation: ED, emergency department.
Quality Assessment
Included cohort studies had methodological quality scores ranging from six to nine, which indicated moderate to high quality. The included case-control study reached a score of nine and the trial had a moderate risk of bias. Quality assessment of the included studies can be found in Supplementary Tables 1-3 (available online only).
Outcomes
Overall Intubation Success Rate—Pooling data from 38 studies that involved 14,207 pediatrics undergoing intubation by paramedics showed an 82.5% overall success rate (95% CI, 0.745-0.832). The group of paramedics who used the muscle relaxant during intubation had a higher success rate of 92.5% (95% CI, 0.877-0.973) in comparison to the group intubated without muscle relaxant with 78.9% (95% CI, 0.745-0.832). In the overall analysis, the group with muscle relaxant and the group without muscle relaxant showed a heterogeneity between groups: (I^2 = 98.3%; P <.001), (I^2 = 94.72%; P <.001), and (I^2 = 98.59%; P <.001), respectively (Figure 2).
Figure 2. Forest Plot for Overall Success Rate of Intubation With and Without Muscle Relaxant.
First Attempt Success Rate—Data syntheses of 4,600 pediatrics undergoing intubation by paramedics showed a 77.2% success rate after the first attempt (95% CI, 0.713-0.832). The group of paramedics who used the muscle relaxant during intubation showed a higher success rate after the first attempt of 79.9% (95% CI, 0.715-0.994) than the group intubated without muscle relaxant with 73.3% (95% CI, 0.616-0.950). The overall analysis of the group with muscle relaxant and the group without muscle relaxant showed a heterogeneity between groups: (I^2 = 94.7%; P <.001), (I^2 = 92.8%; P <.001), and (I^2 = 96.4%; P <.001), respectively (Figure 3).
Figure 3. Forest Plot for First Time Success Rate of Intubation With and Without Muscle Relaxant.
Three or More Intubation Attempts Rate—By analysis of data from 993 pediatrics undergoing intubation by paramedics, only 106 pediatrics needed three or more trials to insert tubes successfully. The prevalence of three or more intubation attempts was 9.0% (95% CI, 0.040-0.140). The pooled data were heterogeneous (I^2 = 86.65%; P <.001); Figure 4.
Figure 4. Forest Plot Showing Intubation More than Three Attempts.
Overall Complication Rate—Of ten studies involving a total of 1,566 pediatric patients reporting the overall complication rate, 384 patients experience complications during intubation by paramedics at 23.4% (95% CI, 0.122-0.346). Pooled data were heterogenous (I^2 = 97.01%; P <.001); Figure 5.
Figure 5. Forest Plot Showing Overall Complications of Intubation.
Esophageal Intubation Rate—Pooling data from 12 studies involving 2,905 pediatrics reporting the esophageal intubation rate revealed that esophageal intubation occurred in 93 with a rate of 3.0% (95% CI, 0.017-0.043); pooled data were heterogenous (I^2 = 81.27%; P <.001); Figure 6.
Figure 6. Forest Plot Showing Esophageal Intubation.
Aspiration Rate—A total of 957 pediatrics pooled from four studies that reported the aspiration rate demonstrated that aspiration occurred in 120 with a rate of 12.9% (95% CI, 0.041-0.216). Pooled data were heterogenous (I^2 = 94.1%; P <.001); Figure 7.
Figure 7. Forest Plot Showing Number of Aspirations.
Discussion
In this systematic review, the overall success rate and associated complications of prehospital intubations of pediatrics done by paramedics were assessed. The prevalence of the overall success rate was 82.5% for all trials, 77.2% success rate after the first attempt, and 9.0% of pediatrics needed three or more attempts. By subgrouping the patients according to utilization of muscle relaxants during intubation, the group that took muscle relaxants showed a high overall success rate of 92.5% and a 79.9% success rate after the first attempt. In contrast, the group without muscle relaxants had a 78.9% overall success rate and a 73.3% success rate after first attempt. In terms of complications, there was an overall rate of 23.4%, 3.0% esophageal intubation, and a 12.9% aspiration rate. Due to its infrequency and difficult nature due to anatomical differences, pediatric prehospital intubation requires expertise and skill. Reference Koslow, Borgman, April and Schauer59 A major issue with multiple intubation attempts or failures, along with complications that frequently occur during advanced airway procedures, plays a significant role in reducing survival chances. Reference Padrez, Brown, Zanoff, Chen and Glomb60
The analysis demonstrated an 82% success for all trials and a 77.2% success rate on the first attempt. Similarly, a previous meta-analysis conducted by Garner, et al Reference Garner, Bennett, Weatherall and Lee17 reported an 88% overall success rate and a 77% successful rate of first attempt. However, the meta-analysis included both physicians and paramedics; nonetheless, paramedics were superior in success rate with 99% while paramedics had a 95% success rate. Additionally, a retrospective study on in-flight intubations on pediatric patients reported a 95% overall success rate and 82% success after first attempt. Reference Tollefsen, Brown, Cox and Walls24 A prospective study on Australian helicopter emergency providers reported a 91% ETI success rate. Reference Burns, Watterson, Ware, Regan and Reid61 In contrast, some studies reported a lower rate of success. A retrospective analysis conducted in nine centers in the United States reported a 64% success rate. Reference Bigelow, Gothard, Schwartz and Bigham62 Furthermore, Boswell, et al reported a 65.5% successful ETI rate, which is less than what was found in this study. Reference Boswell, McElveen, Sharp, Boyd and Frantz53
Previous studies have established that the failure rate rises in younger individuals, likely attributed to variances in laryngeal and craniofacial anatomy, along with age-related equipment needs, rendering ETI more technically challenging in pediatric patients compared to adults. Reference Smith, Gothard, Schwartz, Giuliano, Forbes and Bigham63,Reference Shaw, Bachur, Chamberlain, Lavelle, Nagler and Shook64 A multi-center study conducted on 85,704 patients including neonates, children, and adults intubated by a trained critical care transport team reported that the first attempt was higher in adults at 87.0%, followed by pediatrics at 81.7%, and a low success rate in neonates of 59.3%. Reference Reichert, Gothard, Gothard, Schwartz and Bigham65 A systematic review conducted by Rodriguez, et al revealed that failure in pediatrics was 3.5-times more than in adults. Reference Rodríguez, Higuita-Gutiérrez, Carrillo Garcia, Castaño Betancur, Luna Londoño and Restrepo Vargas66 This evidence in research comparing adult and pediatric ETI rates underscores the importance of specialized prehospital provider training in pediatric airway management. Reference Ono, Tanigawa, Kakamu, Shinohara and Iseki67 This has gone to the extent that the 2020 International Consensus on Cardiopulmonary Resuscitation for Pediatric Life Support recommends bag-mask ventilation due to complications associated with ETI. Reference Maconochie, Aickin and Hazinski68 Further support was received by the 2020 American Heart Association (AHA; Dallas, Texas USA) guidelines that showed the same survival rate comparable between bag-mask ventilation and ETI. Reference Topjian, Raymond and Atkins69
The most common complications associated with ETI include tube misplacement, broncho aspiration, esophageal perforation, hypoxia, atelectasis, or even irreversible brain injury or death from hypoxia. Reference Simons, Söderlund and Handolin70 The complications reported in the study include overall complications (23.4%), esophageal intubation (3.0%), and aspiration rate (12.9%). Consistent with this study’s findings, Garner, et al Reference Garner, Bennett, Weatherall and Lee17 reported that the prevalence of complications with paramedics was 30%-39% and was only 10% in physicians. Also, the most frequent complication was aspiration (12%), the esophageal intubation rate was four percent, and unexpectedly, there was no hypoxia that occurred with paramedics; however, there was seven percent hypoxia with the physician group. A previous meta-analysis conducted by Rodriguez, et al Reference Rodríguez, Higuita-Gutiérrez, Carrillo Garcia, Castaño Betancur, Luna Londoño and Restrepo Vargas66 reported that esophageal intubation was the most frequent complication. While pediatrics encountered potential complications, most of these complications were promptly recognized and resolved; some may not be directly linked to intubation, but are possibly associated with an underlying acute medical condition, such as aspiration. Reference Fawcett, Warner and Cuschieri71
Limitations
The limitations of this study include the absence of a direct control or comparison group, uncertainties, and limited evidence in that combining observational studies and randomized controlled trials leads to significant heterogeneity found in some outcomes. Finally, the different studies included have a variation in defining their pediatrics age group, with some studies including those patients under the age of 12 and others younger than 18 years of age. This variability could affect the validity of the outcomes, as adolescents tend to have airway structures similar to those as adults. All of this affects the generalizability of this study to the general population.
Conclusion
Paramedics have a good successful rate of pediatric intubation with a lower complication rate, especially when using muscle relaxants. Regarding the clinical implications, this study, in alignment with prior research, highlighted the importance of early pediatric intubation. While the performance of paramedics shows promise, there remains a need for continuous training programs to further enhance their proficiency in this critical skill.
Conflicts of interest
There is no conflict of interest declared by any of the authors in relation to the submitted manuscript.
Supplementary Materials
To view supplementary material for this article, please visit https://doi.org/10.1017/S1049023X24000244
