The Success Rate of Endotracheal Intubation in the Emergency Department of Tertiary Care Hospital in Ethiopia, One-Year Retrospective Study

Background Emergency medical care starts with airway assessment and intervention management. Endotracheal intubation is the definitive airway management in the emergency department (ED) for patients requiring a definitive airway. Successful first pass is recommended as the main objective of emergency intubation. There exists no published research regarding the success rates or complications that occur within Ethiopian hospitals emergency department intubation practice. Objective This study aimed to assess the success rate of emergency intubations in a tertiary hospital, Addis Ababa, Ethiopia. Methodology. This was a single institute retrospective documentation review on intubated patients from November 2017 to November 2018 in the emergency department of Addis Ababa Burn Emergency and Trauma Hospital. All intubations during the study period were included. Data were collected by trained data collectors from an intubation documentation sheet. Result Of 15,933 patients seen in the department, 256 (1.6%) patients were intubated. Of these, 194 (74.9%) were male, 123 (47.5%) sustained trauma, 65 (25.1%) were medical cases, and 13(5%) had poisoning. The primary indications for intubation were for airway protection (160 (61.8%)), followed by respiratory failure (72(27.8%)). One hundred and twenty-nine (49.8%) had sedative-only intubation, 110 (42.5%) had rapid sequence intubation, and 16 (6.2%) had intubation without medication. The first-pass success rate in this sample was 70.3% (180/256), second-pass 21.4% (55/256), and third-pass 7.4% (19/256), while the overall success rate was 99.2% (254/256). Hypoxia was the most common complication. Conclusion The intubation first-pass success rate was lower than existing studies, but the overall intubation success rate was satisfactory.


Background
Emergency medical care starts with airway assessment and intervention management. Endotracheal intubation is the definitive airway management in the emergency department (ED) for patients requiring a definitive airway. Anesthetists and or emergency physicians (EPs) perfume intubations with or without drugs [1]. Advanced airway management is a basic skill that every emergency physician (EP) should acquire worldwide [2]. e most widely used emergency airway management is rapid sequence administration of sedation and paralytic agent with tracheal intubation (rapid sequence intubation (RSI)) [3]. RSI performed in critically ill and injured patients in the emergency room has a high risk of failed intubation and other complications than that in the operating room [4,5].
is is caused by several factors such as patients having significant comorbidities; they have not fasted and need to immobilize the cervical spine. In addition, clinical condition of the patient, the experience and training of the clinician, the urgency of the procedure, and the availability of equipment and personnel to support the procedure in the emergency room affect the success and complication of emergency intubation [2,3].
Audit of critical emergency procedures helps to improve training, policy, and clinical practice development. In North America, surveillance studies demonstrated that ED intubations by emergency medicine residents and physicians, largely using a rapid sequence intubation technique, can be performed safely and with high levels of success [6].
A successful first pass is recommended as the main objective of emergency intubation. Study from the anesthesia literature showed that repeated attempt of intubations leads to a higher complication rate [7]. ere are limited data from emergency medicine in the developing world about the success of airway management in the emergency room [8].
ere is a need to fill this knowledge gap in order to identify the frequency of failed intubation and its causation so that clinical outcomes can be improved. e aim of this study was to assess the success rate of emergency intubations in the tertiary hospital, Addis Ababa, Ethiopia.

Methodology
is was a single institute retrospective documentation review on intubated patients from November 2017 until November 2018 in the ED of Addis Ababa Burn Emergency and Trauma Hospital (AaBET Hospital), a major trauma centre in Addis Ababa, which is one of the biggest teaching hospitals in Ethiopia. AaBET currently provides health care services in several specialties: orthopaedics, neurosurgery, plastic and reconstructive surgery, emergency and critical care, and general surgery. AaBET hospital had approximately 20-30,000 annual emergency room visits. It provides outpatient services as well as elective and emergency surgeries. e emergency medicine and critical care residency program, which is a 3-year program, was started in 2015. Residents were given an induction course on emergency medicine and critical care basic topics and practical skills before they start the clinical activity. Likewise, they underwent an airway course and had practical training on manikins. e study included intubations performed with or without the use of drugs. Patients who came intubated from other hospitals were excluded.

Operational
Definitions. "An episode of intubation was defined as the process of intubation for each patient, whereas an attempt at intubation was defined as a single passage of the laryngoscope blade past the lips" [2].
"Difficult laryngoscopy was defined as Cormack and Lehane grade III or IV [2] and difficult intubation as one that requires more than two attempts. "Complications of orotracheal intubations were defined as peripheral oxygen saturation (SpO 2 ) <93%, even if the patient was hypoxic before intubation and had bradycardia<60/min, hypotension requiring support, airway trauma, esophageal or main stem bronchial intubation, laryngospasm, cardiac arrest, or the performance of a surgical airway" [2].

Data Collection.
All intubations in the ED were documented by ED nurse using a purpose designed documentation sheet (Annex-1) as close to the time of intubation as possible. e provider who intubated the patient signed the form after data were filled by the nurse. e documentation form was used by the staff during intubation as a standard protocol of the hospital.
We developed another form (Annex-2) for our analysis which includes age, sex, diagnosis, indication for intubation, anesthetic agents used for intubation, pre-and postintubation vital signs (V/s), immediate complications, and the number of intubation attempts, the intubation personnel, and outcome of intubation.

Statistical Analysis.
Intubation data between November 2017 and November 2018 for one year were analyzed using SPSS version 21.
Descriptive statistics were performed on months of age, sex, diagnosis on admission, indication for intubation, number of patients in whom intubation was attempted, and number of attempts. e study was reviewed and approved by the hospital, Emergency Medicine Department Institutional Review Board.

Results
Out of 15,933 patients, a total of 256 intubations (1.6%) were performed in the study period ( Figure 1). One hundred ninety-four (75.8%) of the intubated patients were male, and 62 (23.9%) were female. e median age was 30 years with an interquartile range of 20 and 49 (Table 1).

Diagnosis and Indication for Intubation.
One hundred twenty-three patients (48.0%) sustained trauma ( Figure 2). e primary indications for intubation were for airway protection 160 (62.5%), followed by respiratory failure 72 (28.1%). An indication for the remainder was not documented.

Attempt and Success
Rate. e first-pass success rate in this sample was 70.3% (180/256), second-pass 21.4% (55/ 256), and third-pass 7.4% [9], while the overall success rate was 99.2% (254/256). ere were only two failed intubations in the one-year period after trial of RSI that required emergency tracheostomy for the diagnosis of tracheal stenosis, and they were performed by surgeons.
Type of intubation versus demographics, level of intubators, final success of intubation, and complication is shown in Table 5.

Discussion
is was the first descriptive study on intubation in the emergency department of AaBET hospital.
In the finding of this study, all ED intubations were managed by emergency residents and physicians. is was not the case in other countries [2,10]. Our study demonstrated poor success rates for first-year residents on the initial attempt related to the other senior residents. On the contrary, the success rate of 70.3 % on the first attempt was not satisfactory and lower than that of studies from other countries, in which the success rate ranged from 80% to 90% [2,[11][12][13][14]. Besides, the majority of the intubated patients had trauma, which could increase the difficulty in intubation and necessitates further training and practice. Lastly, all intubations were done by direct laryngoscope because there was no video laryngoscope in the hospital which could have improved first-pass success [15]. e first-attempt success rate was higher than reports from Japan on intubated trauma patients, where the overall first attempt success rate was 63.8% [16]. e most common indications for intubation were airway protection (61.8 %), followed by respiratory failure.
is could be because most of the intubated patients were trauma patients (123/256).
Also of note, intubation with sedation (129/256) was somewhat more frequent higher than rapid sequence intubation (110/256) in this study. Most studies recommend RSI in the emergency room instead [6,17,18]. In our opinion, this may be because most patients had trauma requiring airway protection anticipating possible difficulty in intubation or because of fear of paralytic drug complication likely implying a lack of confidence in the ability to deal with prolonged apnea. In this study, even though firstyear residents used RSI for intubation more frequently than senior residents, the first-year success rate was poor, which suggests, as would be expected, that experience is more important than the type of intubation. However, further study is needed for why intubation with sedation is used more by intubators. Studies showed first attempt success was higher with RSI [9,19,20]. Based on these studies, the hospital intubators require quality improvement projects and should follow standard recommendations during intubation.
e most frequent agent used as a sedative was ketamine. Other studies have used mostly etomidate as a sedative [1], which was not totally available in our setting. Nonetheless, studies had shown ketamine as a safe alternative to etomidate with no side effect of adrenal suppression [21].    e most commonly used paralytics were succinylcholine, as in other studies [7,22,23].
Oxygen desaturation was the most common complication, similar to other studies.
is study showed that multiple attempts were associated with complications like other studies [7]. Studies suggested proper preoxygenation and apneic oxygenation with nasal cannula will improve desaturation and also first-pass success rate [24][25][26].
Above all, the hospital should have intubation protocol on type of intubation, rescue devices, and others to improve the success rate and to decrease intubation-related complications.

Limitations
ere were several limitations to this study. First and foremost, there was incomplete data for analysis and therefore underlying causes of incomplete data should be explored, with improvements made as needed.
e second limitation was the authors reviewed only the documented intubation sheets, and it was difficult to confirm if all intubations were documented. is could lead to a possible underestimation of overall intubations and other events.
Lastly, the study was not designed to assess the outcome of the intubated patient. Future studies are needed with follow-up of patients to assess mortality and morbidity.

Conclusions
e intubation first-pass success rate of AaBET Hospital was lower than that of existing studies, but the overall intubation success rate was satisfactory.

Data Availability
e data used to support the findings of this study are available upon request to the corresponding author.

Disclosure
ere was no funding for this study.