02/07/2025
During the first Dutch heatwave of the year, I thought to provide some tips for veterinary teams to manage the airway of heat dress and respiratory distress syndrome (RDS) affected dogs, usually displaying anatomically challenging (and often also challenged!) airways.
First I would like veterinary teams to take note of an earlier post on orotracheal intubation procedure and technique in companion animals: https://www.facebook.com/share/p/16VFnnKocg/
With ambient temperatures having been at tropical values and more warm days to come, dog breeds prone to heat stress or RDS, a.o. Pugs, other miniature brachy's, Frenchies, larger brachycephalic breeds (English Bulldog) and more high tensed breeds like the Bull Terrier, Shar Pei & Chow Chow may be presented to your clinic in variable stages of heat stress and RDS.
Here I discuss part 1 of tips and techniques to achieve prompt good laryngeal lumen visualisation and subsequent successful control of your patient's airway (preferably with an orotracheal placed cuffed ETtube)
STEP 1 is the most important: PREPARATION
On days as yesterday, expand the clinic's morning start-up with specific preparations improving preparedness for any difficult airway patient coming your way:
Suction, please?!
Have a functional suctioning device, tubing and several different bore size surgical steel suction tubes and urinary catheters “ready-to use” IN THE PREP room
Orotracheal intubation equipment
Check laryngoscope handle battery packs and check the compatibility of each laryngoscope blade with your current handle, additionally confirming or solving bright light emission performance for each blade prepared.
It may be worthwhile to invest in a Xenon or LED generated light bundle.
Prepare at least 3 compatible Miller-type (straight) blades, in at least a middle and large size format. A spare large size or elongated Miller-type blade can prove useful (see part 2 of this post in a few days).
The curved Mcintosh laryngoscope blades generally do not perform well in companion animals and straight, Miller-type blades should therefore be used with appropriate technique (part 2 of this post later)
Restock Prep room current ET tube sizes (ID 2,0 – 11 or 12 mm) if you have them) from central storage as well as returning intubation aids [stylet, fresh cotton strips, bite block & (non-spring) mouth gags] to -their designated place in- the PREP.
Check oxygen supply and (anaesthesia) equipment for fitness or use, including O2 concentrators (actually switch them on for a few minutes during daily morning checks),l and oxygen cage.
Multiparametric monitoring, anaesthesia circuit integrity and APL device are checked for anomalies, leaks and "employment readiness".
It is prudent to leave capnography-fitted monitoring on, or at least leave it in the stand-by mode from the morning, so to prevent ill-timed extended warm-up time and significant delay in having capnometry at your disposal in case of an airway emergency.
Please be mindful of the fact that any after-market fitted add-on equipment to the prepared anaesthesia circuit, such as "safety” valves / in-circuit pressure limiting devices, are actually degrading the circuit’s performance and deployability, limiting your capability to deal with certain scenario’s requiring brief episodes of high airway pressure [hypoxic drive, severe panting, acute increase in airway resistance, severely decreased total thorax compliance and extra-thoracic applied pressure (severe bloat, CCPR associated chest compressions).
STEP 2
KEEP CALM, you and your team can do this! Any animal coming through that front door is being met with a prepared team determined to help and care for that patient in severe distress.
Let your training and routine kick in with all participating team members and create (i.e. organize!) the situation allowing for you and your team the best conditions to successfully intubate and secure the airway on the first attempt!
STEP 3: It is called in, battle stations!
Worst Case Scenario: Animal is (nearly) unconscious and breathing is extremely labored, yet ineffective or approaching agonal breathing. Mucous membranes are blue to pale and the nares and oral cavity may be occupied with foamy secretum.
Remember, if the situation becomes hyperacute, you only concentrate on your safety and that of your team members and the ABC(DE) approach adopted at initial patient assessment and stabilization.
Delegate talking to and comforting the owner to an (experienced) veterinary licensed nurse, who can do a general history, while you start your clinical assessment already in transit to the prep-room. The cycle of assessment, immediately followed by remedying critical conditions and confirmation of resolution through reassessment, prior to moving on to the next level in the ABC(DE) approach is critical and should be adhered to already from the start (during transit to your preproom).
Forget about 10 min. pre-oxygenation. Guve High flow-by O2 (5-8 L O2/min).
Prioritize on establishing a secure, patent and protected airway. The upper airway needs to be cleared of obstructions (to air and intubator’s visual identification of the larynx).
Assign a second team (TEAM2) -when available - to take a re**al temperature and place an IV canula (or two), for fluid therapy support and thermoregulation.
TEAM1 is going to establish a patent airway for the patieny FIRST
Tip: if a TEAM2 member has done so before, (initial) cannulation of the saphenous vein (in dogs) or the femoral vein (in cats) allows TEAM1 the required working space at the head of the patient to expedited successful orotracheal intubation on the first attempt).
TEAM1: Use extensions (vetwrap ribbons, sturdy cotton strips, drückschlaug IV lining) to keep hands and faces away from the dentures in animals with “diminished sanity” from induced severe stress and altered perception as it progresses towards imminent asphyxiation.
Quickly clear the mouth of most of the obstructive ex-and secreta if present, preferably using a suction device and an extended surgical steel (!!!) large bore suction tube. Do not aim for perfection here, as time may be limited and focus should be on working towards successful first attempt orotracheal intubation.
Alternatively to airway suctioning in case this cannot be provided, the oropharynx may be cleared using 2-3 4 x 4 gauzes in an (elongated) Needle holder, Pean, GI-surgery forceps or bowel clamp and quickly clear the majority of mucus and possible excreta. Avoid pushing the content further backwards towards the larynx, as this increases the likelihood of aspiration and associated complications.
Using a pair of fresh gauzes, attempt to gently but decisively guide the tongue extra-orally and have an assistant take it from you.
STEP 4 airway management; laser focus on optimizing working conditions for YOU (“silent cockpit” rules!)
With proper respect for the animals dentures and disturbed mentation, organize your team members in safely presenting the animal to you for orotracheal intubations, using the extensions and aids (biting block/sturdy mouth gag set) if required to keep everyone safe.
Collect all useful equipment and aids around you commence; Fit the appropriate size miller blade on the handpiece while the team positions the dog in sternal recumbency [unless CCPR has started, in which case positioning for CCPR is prioritized].
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Watch for part 2 of this post in the coming days! Meanwhile (re-)organize your Preproom using the tips discussed here!
