ETT Rotation During Nasal Fiberoptic Intubation
Condition: Dental Caries
MeSH terms: Dental Caries
Study type: Interventional

Summary: 
      A nasal endotracheal tube (ETT) is routinely placed in children and a fiberoptic scope (FOS)
      is commonly used for this purpose. Resistance to the passage of ETT is frequently encountered
      as it is advanced over the FOS for placement into the trachea, since it gets hung up on
      structures of the laryngeal inlet. The aim of the investigators study performed on forty
      children divided in two groups was to study in the pediatric population, whether a 90°
      counterclockwise rotation (CCR) of the ETT prior to advancing through the larynx, by nasal
      approach, prevents it from getting hung up at the laryngeal inlet.
    

Detailed description: 
      A nasal endotracheal tube (ETT) is routinely placed in children and a fiberoptic scope (FOS)
      is commonly used for this purpose. Resistance to the passage of ETT is frequently encountered
      as it is advanced over the FOS for placement into the trachea, since it gets hung up on
      structures of the laryngeal inlet. The aim of the investigators study performed on forty
      children divided in two groups was to study in the pediatric population, whether a 90°
      counterclockwise rotation (CCR) of the ETT prior to advancing through the larynx, by nasal
      approach, prevents it from getting hung up at the laryngeal inlet.Following the approval of
      Nemours Institutional Review Board, and informed consent, forty healthy children were
      included in the study.

      All children were randomly assigned to one of two groups using a computer generated numbers
      table. Group-S (Standard technique): It involved placement of ETT over the FOS with bevel of
      the ETT facing left as is routinely done Group-R (pre-Rotated technique): It involved
      placement of ETT over the FOS with 90° CCR from the beginning so that the bevel of the ETT
      faced posteriorly.

      All children received midazolam premedication prior to coming to the operating room and were
      anesthetized by a standard technique using mask induction with oxygen, nitrous oxide and
      sevoflurane. Intravenous line was placed and rocuronium 0.4 mg/kg body weight was then
      administered to achieve muscle relaxation. Oxymetazoline hydrochloride lotion (Afrin) was
      sprayed in both nostrils to achieve nasal mucosal decongestion and the ETT of appropriate
      size for that age was used for nasotracheal intubation. Small FOS (Olympus LF-P; 2.2 mm
      diameter) was used for cuffed ETT (MallinckrodtTM; Covidien) sizes 4.5 mm ID and under and
      larger FOS (Olympus LF-DP; 3.1 mm diameter) was used for cuffed ETT (MallinckrodtTM;
      Covidien) sizes 5 mm ID and over. ETT was mounted on a FOS and secured near the proximal end
      close to the eyepiece. With head maintained in neutral position, a lubricated FOS was then
      advanced through the right or left nostril (the one that looked bigger) into the larynx and
      once in the trachea, the lubricated ETT was advanced over it.

      An unblinded anesthesia attending associated with the study prepared the FOS and ETT
      according to the randomization, and advanced the FOS into the trachea and the ETT into the
      posterior pharynx. The anesthesia provider advancing the ETT was always one of the trainees:
      student nurse anesthetists (SRNA) or resident who was not a part of the study and was blinded
      to whether or not the ETT has been rotated 90°counterclockwise. The attending member of the
      research team observed as the ETT was advanced by the trainee and made a note of whether or
      not the ETT got hung up. If it did, the research team member withdrew the ETT 2 cm, rotated
      it 90° CCR, and allowed the trainee to advance the ETT one or more times, noting the results.

      Following parameters would be measured:

      Demographic data: age, weight, sex, nostril used and FOS size used; Whether or not ETT got
      hung-up at the laryngeal inlet, Whether or not 90° counterclockwise rotation was helpful with
      ETT advancement through the larynx and number of attempts needed to successfully advance the
      ETT after the 90° CCR.

      Definition of resistance to tube advancement (hung-up ETT):

      Steady but gentle force is generally needed to advance an ETT over the FOS, first through the
      nose and then into the trachea through the larynx. If the ETT were to pass smoothly no change
      in force is generally needed as it goes through the larynx. During advancement over the FOS,
      if ETT came to an abrupt stop and then the same steady force was insufficient to advance the
      ETT through the larynx it was defined as "hung up". If sudden resistance to passage through
      the larynx was encountered indicating that the ETT is hung up at the laryngeal inlet, it was
      then withdrawn about 2 cm, rotated 90° counterclockwise and readvanced through the larynx and
      observation was made if CCR maneuver leads to smoother passage of the ETT through the larynx
      into the trachea without it getting hung-up.

      Statistical analysis: The data will be analyzed in the following manner: Nominal data such as
      gender, nostril used and FOS size compared between the groups using Fisher's exact test and
      numeric data such as age and weight with independent sample t-test. Outcome data such as
      presence or absence of resistance due to hung up ETT will be analyzed with Chi square while
      number of attempts will be analyzed with t-test. Significance was assumed at P< 0.05.
    

Intervention name(s): Pre-Rotated (Group R); No pre-rotation
Intervention type(s): Other; Other
Intervention description(s): In group R, placement of ETT over the FOS was done with 90° CCR from the beginning so that the bevel of the ETT faced posteriorly before it was advanced through the larynx.; ETT was not pre-rotated but rotated only if necessary
Other intervention name(s): 90° CCR
Allocation: Randomized
Intervention model: Single Group Assignment
Masking: Single (Care Provider)
Primary purpose: Diagnostic
Keywords: Nasal intubation; Counterclockwise rotation