Videolaryngoscope vs Classic Laryngoscope in Teaching Neonatal Endotracheal Intubation: a Randomized Controlled Trial.

Methodology

Consent to the study

The principal investigator will approach all pediatric residents to participate in the study. Parents of children will be approached by the principal investigator or the clinical research coordinator either antenatal or on admission to the NICU in the case of an eventual need for the infant of ETI. If the consent is made antenatally, we will insure that it is done by a different physician than the one performing the antenatal consultation.

Training to ETI

In our centre, residents learn neonatal ETI in the simulation centre at CHU Ste-Justine as first year residents when they are taught the NRP at the end of June every year, one week before starting residency training. The procedure is explained and demonstrated on a mannequin (Laerdal Neonatal Intubation Trainer) using the CL by a neonatologist and then residents practice on the same mannequin a couple of times (3-5). Further training is done in the clinical setting on real patients in an opportunistic manner. In both situations, they are supervised by a neonatologist or a senior subspecialty resident who will guide, coach and give them constructive feedback.

Residents who consent to the study will be trained to the use of the VL before randomization. This teaching session will be done similarly to the one described above. The procedure will be explained and demonstrated on a mannequin (Laerdal Neonatal Intubation Trainer) by the principal investigator using the VL and then residents will be offered to practice handling the VL and practice ETI on the same mannequin a couple of times (3-5). They will be supervised by the principal investigator who will guide, coach and give them constructive feedback. This process is to insure that residents depart with the same level of comfort (or discomfort) as the CL.

ETI procedure

In our unit, there are about two to three residents on service at a time. When a patient needs to be intubated priority goes to the resident who is in charge of that patient. In the case where the physician in charge is the neonatologist, the subspecialty resident or the nurse practitioner than a draw is done to decide which resident will proceed to the ETI. The pediatric resident is the first person to attempt an ETI and he is allowed three attempts. If he fails, the subspecialty resident, the respiratory therapist or the neonatologist proceed with the ETI. In the case of an urgent ETI (respiratory or cardiovascular instability, resuscitation, cardiovascular arrest, etc.) or complications during attempts by the resident, the senior physician (subspecialty resident or neonatologist) will proceed with the ETI.

At each ETI procedure, there is a resident, a neonatologist or a subspecialty resident, a nurse and a respiratory therapist. For the study, we will have a second respiratory therapist to assess our primary and secondary outcomes (using a stopwatch) and to collect the necessary data. About six respiratory therapists will be trained for this role, two per 8 hour shift. Monitoring of the child is done using a non invasive arterial blood pressure, an electrocardiogram and a pulse oximeter.

The devices used for the study will be the CL using Miller blades (size 0 and 1), and the C-MAC VL (blades size 0 and 1) developed by Karl Storz Endoscopy. The VL will be used to proceed to ETI indirectly with the use of the video monitor for guidance.

Premedication for ETI consists of a bolus of atropine 20 mcg/kg IV, fentanyl 2-5 mcg/kg diluted in 1 cc total of normal saline and given IV over 3 to 5 minutes, followed by a bolus of 2 mg/kg of IV succinylcholine. Facemask ventilation and preoxygenation is done before and between every attempt. After ETI, confirmation is done by auscultation and carbon dioxide detector, and a chest x-ray is performed to assess position of the tip of the endotracheal tube.

Definitions

1. Intubation is a success if the endotracheal tube is placed in the trachea under the vocal cords It is defined according to usual clinical norms: change in color of the carbon dioxide detector, vapor in the endotracheal tube, thoracic expansion, assessment of bilateral lung air entry, absence of air entry in the stomach by auscultation, and improvement of patient's clinical parameters: heart rate and arterial oxygen saturation.
2. Time to intubation is defined as the time from insertion of the laryngoscope blade in the patients' mouth until it is pulled out.
3. Esophageal intubation is diagnosed when there is absence of clinical signs of a successful endotracheal intubation and possibly air entry in the stomach by auscultation.
4. Right bronchial main stem intubation is diagnosed on chest x-ray.
5. A trial is counted as an attempt if there has been insertion of the laryngoscope blade in the patient's mouth.

Data collection for each intubation.

1. Patient: gestational age at birth, birth weight, sex of infant, post natal age, current weight, required inspired fraction of oxygen, number of ventilated days and number of previous intubations.
2. Intubator: training level, past training experience in pediatrics or neonatology, number of completed rotations in neonatology, and number of neonatal intubations tried, succeeded and failed in the past.
3. Intubation: date (later categorized into weekday and week-end), time (later categorized into day (8h-17h), evening (17h-00h) and night (00h-8h)), indication of intubation, semi urgent or elective intubation, number of attempts, length of each attempt, intubator for each attempt, final position of the tip of the endotracheal tube (including right bronchial main stem intubation), reason for failed intubation (including esophageal intubation), naso or orotracheal intubation, premedication used including doses and supervisor.
4. A survey will be distributed to the resident and the supervisor after each ETI event. The survey will assess the residents' level of confidence in attempting the ETI and will ask the supervisor the level of easiness in recognizing problems with laryngoscopy, endotracheal tube insertion and placement.

Randomization procedure

After consent, randomization will be done by distributing sealed envelopes and will be stratified according to the year of residency training. Residents will initially be randomized to intubate either with the videolaryngoscope (experimental group) or the classical laryngoscope (control group). In a second phase, all students will use the CL for ETI. Each resident is expected to perform at least five and a maximum of ten ETI per method. When a resident has reached ten ETI with the VL, he will change to the CL method. We are planning to obtain 100 ETI in each four groups for a total of 400 ETI.

Methods of data analysis and sample size estimates

Using the CL, the residents in our centre obtained a success rate of ETI of 55% (unpublished data). Assuming an increase of 20% of the success rate to 75% in the experimental group (VL), with an α level of 0.05 and a statistical power of 80%, we need 89 ETI per group. In the second phase, to show a 20% higher success rate in the experimental group (75%) than in the control group (55%) with the same statistical conditions, we need 89 more ETI per group for a total of 356 ETI. In the study, we plan to obtain 100 ETI per group for a total of 400 ETI. In our centre there are approximately 500 ETI a year. Of these, 20% (100) are done in the delivery room and another 20% (100) are done by the subspecialty resident, neonatologist or respiratory therapist because of urgency or difficulty of intubation. Considering a rate of patient recruitment of 60-75%, the study should be completed in 2 years.