Wednesday, April 28, 2010

Bullard laryngoscope


Introduction:

Bullard laryngoscope is a rigid fiberoptic laryngoscope which aids in visualization of larynx and intubation of trachea. Hence it is a very useful tool in the management of difficult airway. It uses fiberoptic technology and mirrors to look around the nook and corners of larynx.

Advantages of Bullard laryngoscope:

  1. It is very useful during difficult intubation
  2. Since it is designed to be inserted with the patient's head and neck in neutral position it can be used safely in patients with unstable cervical spine
  3. It can be used in patients with mouth opening of just 6 mm
  4. It can also be used for nasal intubation procedures
  5. It can also be safely used in paediatric population also since it is available in adult and pediatric sizes

Situations tailor made for the use of Bullard laryngoscope include:

  1. Patients with anteriorly placed larynx
  2. Patients with unstable cervical spine fracture
  3. Patients with upper body burns / trauma
  4. Patients with temporomandibular joint immobility
  5. Patients with micrognathia

Bullard laryngoscope is desgined in such a way that its blade is anatomically curved. At the proximal end an eye piece is provided. It is also provided with a fibreoptic power source attachments. It has two ports i.e. One for oxygenation / instilling medicines / suctioning and the other one for attachment of endotracheal tube stylet. Illumination is provided by fiberoptic light source.

The choice of the size of Bullard scope (adult / pediatric) is made taking into account the height of the patient and the minimal size of endotracheal tube that can be fitted into the stylet.


If the patient is 5 feet and less – pediatric size is preferred
If the patient is more than 5 feet but less than 6 – adult size preferred
If the patient is more than 6 feet tall – adult size with tip extender is used

Procedure:

  1. If adult Bullard laryngoscope is used the tip / blade extender is securely snapped into the laryngoscope blade.
  2. Select appropriately sized endotracheal tube. The endotracheal tube connector is removed temporarily and lubricant is applied over it.
  3. The stylet is inserted into the endotracheal tube until it protrudes out of the endotracheal tube opening
  4. When looking through the optical eyepiece only the stylet should be seen and not the tip of the endotracheal tube
  5. Lubricant should also be applied to the Bullard blade also to facilitate easy insertion. Care should be taken to use only water based lubricants
  6. Attach fiberoptic light source to the laryngoscope

Oral intubation:

  1. Induction drugs are adminsitered to the patient as for regular intubation
  2. Patient should be in neutral position
  3. Place yourself as if you are performing direct laryngoscopy, the axis of the scope should be parallel to patient's axis
  4. The scope is introduced between the teeth into the pharynx and is inserted as close to the midline as possible. The endotracheal tube should be held firmly in the nook of Bullard's laryngoscope while the whole assembly is being advanced.
  5. When epiglottis is visualized, the handle of the Bullard laryngoscope is elevated straight up, the tip of the laryngoscope could be then seen retracting the epiglottis out of the way facilitating direct visualization of laryngeal inlet
  6. The endotracheal tube is advanced over the stylet, and under direct vision is pushed into the trachea between the relaxed vocal cords
  7. The stylet is detached and the scope is gently removed after ascertaining that the endotracheal tube is in place