Surgical Menu.

                             SURGERY FOR BREATHING PROBLEMS.

                     A surgical menu from which to make YOUR CHOICE!


( This article has been written for trainers & owners who would like to be more involved in the decision making process with regard to the surgical management of breathing problems in their equine athletes.)


Recent studies have suggested that many horses which are not performing up to their ability ( given no obvious reason such as lameness or illness) may well be suffering from undiagnosed breathing problems that require surgical attention. In reality the actual number is most likely higher as these were treadmill studies.  It is widely accepted that treadmill endoscopy does not pick up all cases of breathing problems. A treadmill is not a racecourse.


There are several reasons for this apparent increase, including the discovery of ‘new’ problems of the throat and also the realisation that many horses with breathing problems don’t make abnormal noises. These horses are sometimes referred to as ‘silent chokers’.


Another very significant group are horses that have repeated lung inflammation and or infections ( CHRONIC DIRTY LUNGS). They often respond to treatment but then the problem reappears. Mouth breathing is often the cause and surgery to reduce mouth breathing can be considerably less expensive than repeated lung tests and treatment and more importantly YOU GET TO TRAIN THEM!


Today, with these new revelations, it is more important than ever to be aware of the choices you have with regard to dealing with these problems. That is your choice of surgical procedure of which there are many! It is also very important to understand that no surgery will totally ‘fix’ the horses breathing problem but at the same time a well performed and appropriate surgery should significantly reduce the intensity of the problem allowing the horse to attain or regain racing performance. Surgical success is based on regaining form NOT the elimination of noises. Remember many horses make no abnormal noise anyway and others following successful surgery still make some abnormal noises. The opposite can also apply i.e. no noise nut no improvement.


To assist you in making your choice,  a list of the more common surgeries available in Australia today has been compiled. Some are available at your local equine hospital (W) others are less available and more likely to be performed at bigger equine hospitals and universities(LHU) and there are also a few procedures that because of the ‘high degree of technical difficulty’ associated with performing them are only performed by a handful of vets (VL). For the latter you may need to contact the vets directly if they are not already available through your local practise.


The surgeries are divided into two groups . Firstly primary problems of the larynx   or ‘voice box’ which account for approximately a third of throat problems and secondly primary problems of the pharynx or ‘snoring department’ ( two thirds of breathing problems) which may also have secondary elements of laryngeal dysfunction. It is also very important to realise that many horses have MULTIPLE BREATHING PROBLEMS which may be best served by SURGICAL COMBINATIONS or by using SURGERIES THAT DEAL WITH MULTIPLE PROBLEMS. For example a significant number of horses that suffer from laryngeal weakness or paralysis also choke( dysfunction of the pharynx) and may well benefit  from  2 surgeries rather than one. Other problems such as

                                                   (i) epiglottic entrapment  (a)simple (b)intermittent or

                                                                                                     (c)  complicated   

              and                              (ii)axial deviation of the aryepiglottic folds


        usually occur secondarily to mouth breathing which is the primary dysfunction.

In many cases it is best to deal (surgically) with both primary & secondary dysfunction's simultaneously. e.g. (F) & (H)  or  (F) & ( I ). .. See charts below. 


LARYNGEAL - Throat problems


          Primary problems                                              Secondary Problems


(A) Left sided severe weakness                    (B) Axial collapse of vocal folds

       or paralysis


(B) Axial collapse of

       vocal folds


(C) Arytenoid chondritis

       (chronic)


(D) Fourth Branchial Arch                                (E) Aerophagia (swallows

       Defects ( 4BAD )                                               air) & in some cases(A)

( Currently there are no surgeries recommended for 4BAD)


LARYNGEAL - Surgeries    

               

       Surgical procedure                   to treat problems                 availability


(1) Laryngeal prosthesis ( Tieback)           (A)                                       Widely (W)


(2) Laryngeal re-innervation                        (A) & (B) sec.                    Very limited (VL) #

       ( Pedicle Graft)


(3) Bilateral laryngeal ventriculectomy       (B)                                       (W)

      & cordectomy ( Hobday)


(4) Arytenoidectomy (partial)                        (C)                              larger hospitals &

                                                                                                              universities (LHU)


PHARYNGEAL - throat problems


          Primary problems                                              Secondary Problems


(F) Passage of air orally during                                (G) Dynamic  collapse of the 

      inspiration (Mouth breathing)                                    naso-pharynx(choking)

      with lung contamination


(F) Passage of air orally during                                (H) Epiglottic entrapment

      inspiration (Mouth breathing)                                      (Ha) simple

      with resultant lung contamination                              (Hb) complicated [ulcerated]

                                                                                                 (Hc)  intermittent


(F) Passage of air orally during                                (I)  Axial deviation of the

      inspiration (Mouth breathing)                                   aryepiglottic folds

      with resultant lung contamination


(F) Passage of air orally during                                (J) Dorsal displacement of

      inspiration (Mouth breathing)                                    the soft palate (DDSP)

      with resultant lung contamination


(G) Dynamic collapse of the

       naso-pharynx ( choking)


NOTE - (F) and (G) can also occur in the reverse order or independently.


NOTE - (F) Mouth breathing . Air that passes to the lungs via the mouth instead of the nostrils carries with it contaminates of food particles, saliva and oral bacteria that when deposited in the lungs can increase the likelihood of lung inflammation, infection and bleeding.


PHARYNGEAL - surgeries


         Surgical procedures                 to treat problems                        availability


(5) Palatal caudal resection                        (D)                                          (W)

      ( Staphylectomy)


(6) Thyro-hyoid prosthesis                     (F),(G),(J)                                  (LHU)

        ( Laryngeal Tie-forward)  


(7)  Combined Staphylectomy and             (J)                                          (W)

       Sternothyroideus Muscles Transection

        (Llewellyn Procedure )


(8)  Aryepiglottic fold laser resection          (I)                                          (LHU)


(9)  Aryepiglottic fold open resection         (I)                                            (W)


(10) Epiglottic entrapment splitting           (Ha)                                        (W)

                    (hook Knife)   


(11) Epiglottic entrapment  open              (Ha), (Hb)                               (W)

             resection                                          (Hc)                                       (LHU)


(12) Epiglottic entrapment laser               (Ha),(Hb)                             (LHU)

        splitting and  resection  


(13)  Laser Palatoplasty                          (J)                                             (LHU)

         (dorsal Palate)


(14)  Tension Palatoplasty (TPP)          (F),(G),(J)                                 (VL) ##


(15) Oral Palatopharyngoplasty            (F),(G),Ha),(Hb),(Hc),(I),(J)     (VL) ##

         (OPP) ‘Ahern procedure’ .             ( I = A/E fold reduction)


(16) OPP followed by Max-TPP            (F),(G),Ha),(Hb),(Hc),(I),(J)      (VL) ##       

         (Maximum -                                       ( I = A/E fold reduction)

                Tension Palatoplasty)  


N.B. Thermal firing of the ventral soft palate ( which is performed in the UK) 

          is not permitted in Australia where firing is banned.                                     


RESULTS-  vary depending on the experience of the surgeon.

Therefore a very simple RULE OF THUMB is that when seeking an opinion on a ‘particular procedure’ ask someone who has personally performed a good number of these.. There is no substitute for experience. Opinions by way of what one may have read or heard from someone who told someone who knows someone else who tried a few can be misleading. If you really want to know about a surgery then get it from the horses ( or horse vets) mouth!


Happy racing


Tom Ahern BVSc MRCVS