Nasal Intubation Guide

Introduction 

As a student, I found it very difficult to find a good guide online or in text books on how to setup and perform nasal intubations. This seemed very strange to me, as it is one commonly performed airway management techniques, especially in dental procedures and surgeries involving the mandible. Without knowing what to set up or how to prepare, nasal intubations always seemed like a very daunting task. This tutorial is here to bring it down to size. It really isn't much more difficult than a standard laryngoscopy, as long as you know what to do and how to prepare. This tutorial is here to show you a common setup and describe the procedure itself. Follow these simple steps and you'll be able to safely secure your patient's airway while providing adequate surgical exposure for the surgeon.

Setup

There are a few items from a standard ETT setup that you will want to make sure you have ready to go.

• Appropriately sized blade with working handle - Mac 3, Mac 4, Mil. 2, Mil 3. 
• Appropriately sized oral airway - It is vital that we are able to mask ventilate our patient.

Here's where things start to change up. There are a number of different items. Sometimes you can find them in the OR, other times you may need to go to pharmacy or the anesthesia techs for help.

• Pharmacy Nasal Pack - At some hospitals you can go to pharmacy and ask for a pack by name. They may have all the components compiled already, however, in some hospitals you may just have to ask for the individual components. 

1. Afrin nasal spray - This spray is an alpha adrenergic agonist. It causes vasoconstriction of the vessels in the nasal cavity to reduce the risk of bleeding. As you will see shortly, it can also be used to help us identify which nasal cavity in which to place the ETT.  

 

1. Lidocaine Jelly - Many practicioners will use this as lubricant for nasal trumpets and ETT. If not available, you can use a standard water based lubricant. 

• Magill forceps - They make a smaller version for pediatric patients. This will later be used to help advance the tube through the vocal cords.  

• Nasal trumpets of varying size - Some attendings like to use these to dilate out the nasal cavity before passing the ETT. If you look at the back of the packaging, usually the outside diameter will be labeled in mm. In the picture below, the size is shown as 9.3mm. The outside diameter of the ETT is usually listed on it's package as well. I like to compare the two and have one nasal trumpet with an OD just smaller than the ETT and then one about the same size OD or slightly larger. Before going to get the patient, you can cover the trumpets in the lidocaine jelly and leave wrapped in the package. 

• Nasal RAE endotracheal tubes - The ETT's are designed to pass through the nasal cavity, through the vocal cords, and can be secured out of the surgical field. A tube is pictured below. The sizing of nasal rae tubes generally follows the same guidelines as regular ETT's. It is a good idea, however, to have a size above and below what you anticipate using, just in case. 

• Warm bottle of NS - Before going to get the patient grab a warm bottle of NS from the core. If you don't know where to find it, ask one of the nurses, they should be able to tell you. Place the nasal rae tubes in the warm bottle of NS. It will make the tube more compliant ad easier to pass through the nasal cavity. 

In the pre-op area

In adults, you can take the Afrin nasal spray and ask them to spray it in each nostril themselves. Pediatric patients wont likely tolerate this and you will likely have to use the spray during bag mask ventilation. If the patient is able to use the spray in the preop area, take a look at their nostrils afterwards. In general, the nostril with the smaller diameter after using the spray will have the larger nasal cavity and will be ideal for placing the tube.

This is also a good time to look for any CT scans or images that may be useful. For one, it will be able to accurately give you an idea of the size of the nasal cavities and if there are any obstructions. Secondly, if the surgery is fixing a mandibular fracture, it is likely the patient will have a limited mouth opening. A CT scan can give you an idea if this limited opening is due to pain (in which case general anesthesia will relax the patient and it shouldn't be an issue) or if it is a physical obstruction related to the injury (this is more a cause for concern and should be discussed with your attending. If it really an issue, nasal fiberoptic intubation may be your next option).

In the operating room

Initially, you will do things as you normally would in the OR. Get the patient situated on the OR table and connect the standard asa monitors and begin to pre-oxygenate. While preoxygenating, it is a good idea to make sure that all of your supplies are ready to go. Open your Magill forceps, remove the ETT from the warm saline and put some of the lidocaine jelly/lube on the end of it, and lube nasal trumpets if you have not done so already.

Push your induction drugs when you are ready and asses if the patient is asleep. Once asleep, bag mask ventilate as you normally would. Feel free to turn on some volatile agent. While masking, tape the eyes and spray some afrin in the nostrils if you did not do so in the preop area. After you have done this, pass the smaller nasal trumpet into the chosen nasal cavity. Give a few breathes with thi sin place. Remove this trumpet and place the larger one and give a few more breathes. The nasal cavity should now be properly dilated and you are ready for intubation.

Take the nasal rae ETT and introduce into the nasal cavity. The tube should enter at a 90 degree andle to the OR table. It should pass easily. If you meet resistance, try to reposition or consider using the other nostril. Don't advance the tube too far just yet. At this point, take you laryngoscope and DL as you normally would to gain a view of the vocal cords. Once you have your view, ask for someone to advance the tube until it is in your field of view, if it is not already. Now take the magill forceps and place them in the oral cavity. You will use them to grab and direct the ETT in the direction of the cords. Just be careful not to grab the cuff, as you can rupture it. ALWAYS grab distal or proximal to the cuff. Once in line with the vocal cords, again ask someone to advance the tube and visualize it as it passes through the cords. Remove the blade and forceps, inflate the cuff, and connect your circuit. Once proper placement is confirmed, you can secure the tube. Sometimes the surgeon will stitch it in place, so ask them if this something that they are going to do.