Nasal Intubation Using a Parker Flex-tip Endotracheal Tube Compared to a Nasal RAE Tube
Condition: Epistaxis
MeSH terms: Epistaxis
Study type: Interventional

Summary: 
      The purpose of this study is to determine the degree of epistaxis following nasal intubation
      with either a nasal endotracheal (RAE) tube with bevel facing left or Parker Flex-Tip
      endotracheal tube with bevel facing posteriorly

      The investigators hypothesize that a Parker Flex-Tip endotracheal tube when inserted with
      bevel facing posteriorly during nasal intubation may reduce the incidence of epistaxis intra
      and post-operatively. The investigators propose that using this style of endotracheal tube
      improves patient safety and comfort and facilitates ease and success of nasal intubation.
    

Detailed description: 
      1. Purpose

           To investigate and describe the use of a Parker Flex-Tip endotracheal tube (ETT) with a
           posteriorly facing bevel for nasal intubation at Vancouver Coastal Health (VCH).

           The investigators wish to demonstrate that a Parker Flex-Tip ETT with a posterior facing
           bevel eases ETT insertion and reduces epistaxis compared to a standard nasal RAE
           endotracheal tube (RAE ETT) currently used at VCH. The investigators propose that using
           this method improves performance and reduces complications of nasal intubation.

        2. Hypothesis

           Our hypotheses are:

             -  That a Parker Flex-Tip ETT with a posterior facing bevel may reduce the incidence
                of epistaxis

             -  That a Parker Flex-Tip ETT with a posterior facing bevel may allow the
                anesthesiologist to successfully nasal intubate with more ease and fewer attempts.

             -  That use of a Parker Flex-Tip ETT with a posterior facing bevel for nasal
                intubation is acceptable to anesthesiologists and patients

        3. Justification

           Justification for developing a new technique Endonasal intubation is a widely performed
           technique that allows administration of anesthetic during oral, dental and maxillofacial
           surgeries while allowing unimpeded access to the surgical site. Nasal intubation poses
           several challenges not encountered in oropharyngeal intubation. These include advancing
           the endotracheal tube through the highly vascularized delicate mucosa of the nasal
           passage, past protruding turbinates, and maneuvering through the sharply angulated
           nasopharyx to access the trachea (Hall).

           The most common complication associated with endonasal intubation is epistaxis due to
           nasal abrasion, most commonly in the anterior part of the nasal septum, which can range
           from mild blood tinged mucus to massive epistaxis (Tintinalli, O'Connell, Hall). The
           risk of epistaxis increases with the use of excessive force, large endotracheal tube,
           repeated unsuccessful attempts and abnormal pharyngeal anatomy (Hall ). Rarer
           complications of nasal intubation include traumatic avulsion of the turbinates,
           turbinate fracture, retro pharyngeal laceration, and bacteremia (Williams, Hall,
           Dinner).

           Common techniques used to reduce the risks associated with nasal intubation include the
           use of vasoconstrictors in the nasal canal, lubrication of the endotracheal tube,
           selection of a smaller tube, mechanical dilatation of the nasal cavity, deliberate
           maneuvering of the tube during intubation (Hall). Other more complicated techniques have
           included thermosoftening and using a curved tip suction catheter to help guide the
           endotracheal tube (Kim, Morimoto, Wart, Seo). Overall these precautions and
           interventions are complicated and often ineffective in reducing complications.

           The main justification for our study is the finding from a recent study by Sugiyama .
           (2014) that using a Parker Flex-Tip ETT with a bent flexible tip, and advancing with the
           aid of an anterior flexed stylette with bevel facing posteriorly reduced the incidence
           of epistaxis to 4% compared to 50%, with a standard ETT. In our practice the
           investigators have noticed epistaxis to be present more often than not with the present
           nasal RAE ETT. However, the investigators have not quantified this scientifically. This
           significant reduction of epistaxis with a Parker Flex-Tip ETT, offers a simple and
           effective way to enhance patient safety and improve user ease when nasal intubation is
           indicated, and will improve the quality of care in our practice.

           The Parker Flex-Tip in our proposed study is identical to the Parker Flex-Tip used in
           the study by Sugiyama. Based on the findings by Sugiyama , the tube should allow the ETT
           to curve towards the oropharynx as it approaches the curve of the nasopharynx and
           therefore reduce impact and damage to the pharyngeal mucosa. Positioning the bevel to
           face posteriorly will allow the tube to slide along the posterior wall and reduce the
           risk of turbinate abrasion as it is advanced. The soft and curved distal tip presumably
           curls inward when it is advanced past the curve and a larger surface area of the tip
           comes into contact with the mucous membrane, reducing the pressure on the pharyngeal
           mucosa. Overall, the investigators predict that these modifications will increase ease
           of insertion and reduce the number of attempts to successful intubation, which should
           improve user ease and decrease risk of pharyngeal bleeding.

           The investigators aim to conduct a clinical study in 20-30 patients randomized to either
           the standard nasal RAE tube currently employed in our hospital or the Parker Flex-Tip
           ETT to demonstrate the feasibility of our technique in reducing endonasal complications
           at VCH.

        4. Objectives - Primary and Secondary

           Our primary objective is to describe the incidence of epistaxis with the use of a Parker
           Flex-Tip endotracheal tube with bevel facing posteriorly during nasal intubation.

           Our secondary objectives are to describe the ease of use of a Parker Flex-Tip
           endotracheal tube with bevel facing posteriorly, as well as patient and operator
           satisfaction with the technique.

        5. Research Methods

           To fulfill our objectives the investigators aim to perform a study in a clinical phase.

           A. Clinical Phase:

           The investigators plan to perform a clinical randomized study assessing the ease of use
           and complication rate associated with of a Parker Flex-Tip ETT with a posterior facing
           bevel during nasal intubation compared to a standard nasal RAE ETT.

           Study Population:

           Between 20 and 30 ASA physical status I or II patients undergoing oral or maxillofacial
           surgery where a nasal intubation would be appropriate for surgical anesthesia.

           ASA Physical Status 1 - A normal healthy patient

           ASA Physical Status 2 - A patient with mild systemic disease

           ASA Physical Status 3 - A patient with severe systemic disease

           ASA Physical Status 4 - A patient with severe systemic disease that is a constant threat
           to life

           ASA Physical Status 5 - A moribund patient who is not expected to survive without the
           operation.

           Patients who have documented deformities that will hinder nasal intubation, patients
           with a history of trauma or surgery in the area of interest, a history of epistaxis or
           -coagulopathies will be excluded from the study. Opioid tolerant patients taking more
           than 30 mg oral morphine equivalent will also be excluded from the study.

           Randomization and Blinding:

           A staff member with no clinical involvement in the study will insert the group
           allocation into an opaque envelope and seal the envelope. At the induction of anesthesia
           the envelope will be opened and the anesthesiologist will prepare the assigned tracheal
           tube and insert it.

           Patients will be randomly allocated to one of two groups differentiated by the type of
           endotracheal tube used (either a standard nasal RAE endotracheal tube with the bevel
           facing left or Parker Flex-Tip ET tube with bevel facing posteriorly).

           Intra operative measurements will be obtained and recorded by the attending anesthetist.

           The assessment of the presence of a post operative nose bleed or nasal pain and
           discomfort will be measured and recorded by an investigator who is not the attending
           anesthetist for the case and who is blinded to the group allocation.

        6. Interventions

      Patients who are scheduled for maxillofacial surgery where nasal intubation would be
      appropriate to deliver surgical anesthesia and who consent to participate will be studied. A
      single experienced operator with at least 5 years of clinical anesthetic experience will
      perform the clinical examination and intubation. Routine monitors will be applied and
      peripheral intravenous access will be established. Oxygen will be given via face mask.
      Anesthesia induction using intravenous fentanyl (2.5 mcg/kg), propofol (1-2 mg/kg) and
      rocuronium (0.5-1mg/kg) will be administered for muscle relaxation. The nostril that the
      patient finds easy to breathe through will be chosen for intubation. If nostril conditions
      are the same on both sides the right nostril will be preferred for intubation. The tracheal
      tube (internal diameter [ID] 7 mm for males or 6.0 mm for females) will be coated with
      lubricating gel and gently inserted into the patients' selected nostril. Those assigned to
      the Parker Flex-Tip endotracheal tube will have a curved stylette inserted in the tube before
      induction and the bevel will be inserted facing posteriorly. Those assigned to the standard
      nasal RAE endotracheal tube will have the bevel facing leftward. Both study groups will have
      the ETT warmed and lubricated prior to insertion.

      If no resistance of the either endotracheal tube during advancement into the oropharynx is
      noted it will be defined as "smooth", and will be inserted into the trachea using direct
      laryngoscopy. In patients assigned to the Parker Flex-Tip endotracheal tube, the stylette
      will be withdrawn from the tube immediately after the tube passes through the nasopharynx and
      the tube will then be advanced into the trachea by direct laryngoscopy. If resistance is
      noted on insertion of either ETT it will be recorded as "impinged" and a mark will be made on
      the tube corresponding to the depth of insertion into the nostril to allow the distance
      between the tip of the tube and the mark to be measured. The assessment of the ease of
      insertion will only be made on the first attempt, with no manipulation applied against
      resistance.

      The degree of epistaxis will be assessed by a blinded independent investigator immediately
      post intubation and up to 5 minutes post intubation, and along with ease of insertion,
      recorded. Quantity of epistaxis will be measured by swabbing the nasopharynx with a dry swab
      and measuring the difference in weight gain between the dry swab and blood soaked swab.
      Epistaxis will be evaluated based on the criteria established by Sugiyama . Four grades will
      be used:

        1. No epistaxis, no blood observed on either the surface of the tube or the posterior
           pharyngeal wall

        2. Mild epistaxis with blood apparent on the surface of the tube or posterior pharyngeal
           wall

        3. Moderate epistaxis with pooling of blood on the posterior pharyngeal wall

        4. Severe epistaxis with a large amount of blood in the pharynx impeding nasotracheal
           intubation and necessitating urgent orotracheal intubation

      7. Study Outcome

      The principal outcome is reduced epistaxis using the Parker Flex-Tip endotracheal tube when
      compared to the standard nasal RAE ETT with a left facing bevel.

      Secondary outcomes will include:

        -  Ease of tube insertion

        -  Number of attempts to insert tube

        -  Post-operative patient nasal pain (Visual Analogue Score anchored at 0= no pain & 10=
           maximum pain) and satisfaction scores

        -  Operator assessment of procedure

           8. Statistical analysis

      Sample size between 20 and 30. Using the results of Sugiyama (2014) study the investigators
      predict that the incidence of epistaxis will range between 50% and 4% in the RAE and Parker
      Flex-Tip group respectively. Fisher's exact test determined the sample size of at least 7 per
      group using α = 0.05 (two sided) and a power of 80%.

      Descriptive statistics will be used to analyze success rate and to present the information
      gathered.
    

Intervention name(s): Nasal Intubation with nasal RAE endotracheal tube; Nasal Intubation with Parker Flex-Tip endotracheal tube
Intervention type(s): Device; Device
Intervention description(s): A single experienced operator with at least 5 years of clinical anesthetic experience will intubate using the standard nasal RAE endotracheal tube with bevel facing leftward.; A single experienced operator with at least 5 years of clinical anesthetic experience will intubate using the Parker Flex-Tip endotracheal tube with the bevel facing posteriorly.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Health Services Research
Keywords: Epistaxis; Nasal Intubation; Maxillofacial surgery