EQUINE | CPD Article
Treatment
Rapid and aggressive therapy is required once a
diagnosis of pleuropneumonia is made 7 as treatment
costs, duration of therapy and positive outcome or
return to athletic function are directly influenced by
delay 5 16 . As most horses will need to be transported
to a facility where pleural drainage and lavage,
intravenous fluid administration and monitoring
for complications can be done 17 , broad spectrum
antibiotics should be administered prior to referral (in
consultation with the referral center), regardless if a
pleural effusion sample has been obtained or not.
Antimicrobial drugs to be considered initially 3 6 9 are
B-lactam penicillins: 44000 IU/kg IV q4-6hr [broad
spectrum; anaerobes], aminoglycosides: gentamicin:
6.6mg/kg IV q24hr [aerobes, gram negative] and
metronidazole: 20mg/kg IV q8hr, or 35mg/kg per
rectum q12hr 3 [anaerobes]. Cephalosporins: ceftiofur
: 2.2 -4.4mg/kg IM q12hr 3 may also be considered.
Once the culture and sensitivity results are received,
antimicrobial therapy should be re-evaluated and
adjusted accordingly 2.
Haematology and biochemistry may reveal an
inflammatory leucogram – neutrophilic leucocytosis,
hyperfibrinogenaemia and hyper gammaglobuline-
mia 3 10 11 . The patient should remain on parental antimicrobial
administration for at least 7 – 14 days 3 9 11 , and should
exhibit good clinical improvement3 before switching
to oral medication 9 11 . Oral antimicrobial therapies to
consider are enrofloxacin, erthyromycin, rifampicin
and chloramphenicol (with the consideration of
human health risk ) 11 . Trimethoprim sulphonamides
are seldom effective given the type of organisms
implicated 3 . Drug cost, availability, route and owner
compliance 3 must also be considered 11 as the horse
may require medication long term; in some cases for
at least 2 -4 months 11 .
Arterial blood gas values may indicate the extent of
the respiratory compromise and hypoxemia 10 . The patient’s hydration status is very important
and must be assessed before the administration of
Images of a chest drain in the right hemithorax draining a
haemorrhagic effusion
38
• Equine Health Update •