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Israel Journal of Veterinary Medicine  Vol. 69 (3)  September 2014 157 Toracic injury in a flly
INTRODUCTION
Toracic injuries are relatively uncommon in horses and may
follow blunt or penetrating trauma (1). Te most common
cause of trauma is collision with an inanimate object (2).
Equine thoracic trauma may require rapid emergency measures
in order to save the horse from life-threatening complications
such as pneumothorax, hemothorax, pleuritis, diaphragmatic
hernia, and damage to the lungs, heart or blood vessels. Patient
stabilization is the primary objective prior to deciding upon the
course of treatment. Torough evaluation, and determination
of location and depth of the wound, must be performed. One
must keep in mind that extra-thoracic injuries (e.g. abdominal,
spinal) may occur in association with thoracic trauma (1). Deep
wounds and those caudal to the sixth rib are more likely to
involve the abdomen; moreover, horses with axillary wounds
should be monitored for delayed respiratory distress until the
wound has completely healed (2). Clinical fndings are variable
and may be associated with external thoracic injuries, which
may cause muscle damage, blood vessel laceration, rib frac-
ture and spinal trauma that in turn may lead to pain, shock or
neurological signs. Tose horses with internal thoracic trauma
often present with respiratory distress. In addition, horses with
concurrent abdominal trauma or diaphragmatic herniation may
develop signs of colic (1, 2). True penetrating wounds of the
thorax and/or abdomen carry a guarded prognosis due to pos-
sible complications such as pneumothorax, septic pleuritis, etc.
(3, 4). In contrast, it was previously stated that a distinction
should be made between penetrating thoracic injuries occur-
ring alone and those with an additional extra-thoracic injuries,
since the former carries a favorable prognosis (2).
Tis report describes a case of a penetrating thoracic in-
jury in a pony flly, the course of treatment and the long-term
results.
CASE DETAILS
History
A 2.5-year old, 300 kg pony flly, was referred to the Koret
School of Veterinary Medicine – Veterinary Teaching
Successful Management of a Penetrating Toracic Injury in a Pony Filly
Bar, R. and Kelmer, G.
Large Animal Department, Veterinary Teaching Hospital, Koret School of Veterinary Medicine, Robert H. Smith Faculty of
Agriculture, Food and Environment, the Hebrew University of Jerusalem, Rehovot, Israel.
* Corresponding Author: Dr. Gal Kelmer DVM, MS, DACVS, DECVS, Large Animal Department, Veterinary Teaching Hospital, Koret School of
Veterinary Medicine, Robert H. Smith Faculty of Agriculture, Food and Environment, Te Hebrew University of Jerusalem, Beit Dagan, 76100, Israel.
Tel: 03-9688532, Fax: 03-9604079, Email: gal.kelmer@mail.huji.ac.il
ABSTRACT
A 2.5-year old, pony flly, was referred to the Koret School of Veterinary Medicine – Veterinary Teaching
Hospital (KSVM-VTH) with a traumatic open pneumothorax, hemothorax, large chest defect, minor
lung laceration, and multiple rib fractures. Te flly was initially stabilized via intravenous fuids, oxygen
supplementation and blood transfusion and then went through standing surgical repair of the fractured
ribs, followed by chest wall defect closure. Ten, the thorax was evacuated from air and fuids by placing a
ventral and dorsal thoracostomy tubes. Te mare was hospitalized for fourteen days, during which time she
received intensive medical care including; broad spectrum antimicrobials, non-steroidal anti-infammatory
drugs, prophylatic treatment for laminitis, thoracic lavage including intra-thoracic antibiotic administration
and daily wound care. Upon follow up with the referring veterinarian, three years later, the flly returned to
work showing no signs of exercise intolerance or any other clinical signs.
Keywords: Toracic injury, Pneumothorax, Horse, Surgery.
Israel Journal of Veterinary Medicine  Vol. 69 (3)  September 2014 Bar, R. 158
Hospital (KSVM-VTH), with a left sided penetrating
thoracic injury, following a direct collision with a paddock
pole. Prior to arrival at the hospital, the flly was given non-
steroidal anti-infammatory drugs (NSAID’s) (funixin
meglumine) and antibiotics (penicillin, gentamycin) by the
referring veterinarian. Te flly was routinely vaccinated for
tetanus, rabies and infuenza.
Clinical examination
Te flly was depressed, showing signs of labored breath-
ing, tachypnea (28 breaths/minute), tachycardia (92 beats/
minute) with weak palpable pulse, and cold extremities. Her
rectal temperature was 38.5°C. Mucus membranes were
pale, and the capillary refll time (CRT) was prolonged (>2
sec); dehydration was estimated at 6-8%. At the left side of
the thorax there was a 25 cm long, deep laceration oriented
dorso-ventrally with fractured rib ends protruding from it. In
addition, there was blood actively oozing out of the thoracic
cavity. Moreover, careful inspection via strong illumination
into the thoracic cavity revealed a collapsed lung. Te diag-
nosis was open pneumothorax that seemed unilateral at this
stage, fractured ribs, hemothorax, and shock (Figure 1). No
extra-thoracic injuries were detected.
Clinical pathology
Initial laboratory data revealed: mild leukopenia (white blood
cell count, WBC - 4.39×10
9
/L, reference 5.40-14.3×10
9
/L),
mild anemia (red blood cell count, RBC - 7.07×10
12
/L, refer-
ence 6.80-12.9×10
12
/L, and packed cell volume, PCV = 27%,
reference 32-52%), low total solids (TS - 5.2 g/dL, reference
5.7-7.9 g/dL), slightly high urea (urea – 41.1 mg/dL, refer-
ence 10-40 mg/dL), and serum creatinine was within range
(Cr - 1.63 mg/dL, reference 0.9-2.0 mg/dL).
Treatment and hospitalization
An extended use intravenous (IV) catheter (Milacath
®
,
MILA International, INC, Erlanger, KY, USA), 14 gauge,
was inserted in the left jugular vein, IV fuids (Lactated
Ringers solution, Teva Medical Ltd., Ashdod, Israel) were
administered at a bolus fow rate, and nasal insufation of
oxygen, at a fow rate of 15 l/min, was initiated (Figure 1).
Additional antibiotic coverage was provided by adding met-
ronidazole (Metryl 100%, Vetmarket Ltd., Petach Tikva,
Israel), and penicillin G sodium (Sandoz GmbH, Kundl,
Austria). Te flly was sedated, using a combination of deto-
midine hydrochloride (Domosedan
®
1%, Orion Pharm,
Turka, Finland) and butorphanol tartrate (Torbugesic
®
1%
Fort Dodge Laboratories, Fort Dodge, IA, USA) (0.01 mg/
kg intravenously (IV)) given once and followed by constant
rate IV infusion (CRI; 5mg/h) of both drugs. Regional
analgesia was achieved by 2% mepivacaine hydrochloride
(Mepivacaine, Ceva/Nature vet, NSW, Australia) injected
into the subcutaneous tissue, muscle layers and exposed
parietal pleura. Te chest wound was thoroughly explored,
irrigated gently, using sterile saline solution, and debrided.
Tree consecutive ribs were fractured (ribs 9-11) and access
for repair was achieved by performing a 20 cm incision, 20
cm caudally to the original wound, oriented dorso-ventrally
and extending through the skin and chest wall musculature.
Two ribs (10 and 11) were amenable for reduction and sta-
bilization using 1.25 mm thick cerclage wire. A 2mm hole
was drilled near the rib ends and the two parts were wired
together in a simple interrupted fashion (Figure 2). Te third
rib (9) sufered a comminuted fracture in which the bone
fragments were removed, and rib edges were smoothed using
rongeurs. Toracostomy tubes (26 gauge), dorsal and ventral,
were inserted into the thorax via a 1 cm skin incision made
one intercostal space caudal to the intended portal of entry.
Te tube/trocar complex advanced under the skin and in-
serted into the thorax along the cranial edge of the rib, and
once inside, the trocar was withdrawn. Te dorsal tube was
inserted at the 13 intercostal space, and the ventral one at the
ninth intercostal space. A Heimlich valve (Becton, Dickinson
and Company, New Jersey, FL, USA) was attached to the
dorsal tube, while the ventral tube was just sealed with a
Figure 1: Image of the flly upon admission to the hospital.
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (3)  September 2014 159 Toracic injury in a flly
catheter cup. Since there was evidence of continued tho-
racic bleeding which was considered signifcant according
to the clinical signs of shock and the decrease in packed
cell volume (PCV = 25%) and total solids (4.9 g/dL) during
the surgical procedure, the flly received three litters of fresh
whole blood from a cross matched donor. Both wounds, the
original laceration and the surgical incision, were closed in
3 separate layers. Te muscles were sutured using PDS 1
(Assucryl 1, Assut sutures, Switzerland) in a simple continu-
ous pattern, (Figure 3) the subcutaneous tissue was closed
using PDS 2-0 (Assucryl 1, Assut sutures, Switzerland) in
the same pattern, while the skin was closed with Nylon 0
(Interlon 0, IntroMedix, Israel) in a simple interrupted pat-
tern in the original wound and Ford interlocking pattern in
the surgical incision. Moreover, a closed drainage system (a
Jackson-Pratt drain with a container) was placed against the
rib cage underneath the muscle layer during closure of the
original wound (Figure 4).
Following wound closure and evacuation of air from the
thorax, there was a signifcant improvement in the flly’s
clinical condition, her breathing pattern and rate improved
and she seemed alert. Moreover, postoperative radiographs
revealed both lungs to be properly infated and the fractured
ribs in good reduction.
Postoperative care
During the frst ten days following surgery, the flly was
kept in strict stall rest, at which point short hand walking
was allowed every day. Moreover, the flly was monitored
frequently for vital signs, pain, demeanor, appetite, and in-
testinal activity. Special attention was given to the develop-
ment of any sign of respiratory distress. In addition, wound
appearance, type and quantity of secretions collected through
the closed drainage system, were also monitored. Te flly
was given broad spectrum antibiotics; initial treatment in-
cluded penicillin G sodium (25 × 10
3
U/kg BW, IV, QID),
gentamycin (Gentaveto-5 pro injection, Biove Laboratories,
Arendonk, Belgium, 6.6 mg/kg BW, IV, SID) and metro-
nidazole (15mg/kg BW, PO, TID). Te flly also received
IV fuids (lactated Ringers solution) at a fow rate of 1l/hr,
anti-infammatory drugs funixin meglumine (Mefosyl,
Norbrook laboratories Ltd, Newry, Ireland, 1 mg/kg BW,
IV, BID, six treatments), anti-endotoxemia medication -
polymyxin B sulfate (Vi-Polyxin, Teva Ltd., Petach Tikva,
Israel, 6000 iu/kg BW, slow IV, BID, four treatments), and
Figure 2: Intra-operative image of the stabilization of ribs ten and
eleven using cerclage wire (black arrow).
Figure 3: Intra-operative photograph demonstrating muscular layers
closure using simple continuous pattern in both the primary wound
(black arrow) and surgical incision (white arrow).
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (3)  September 2014 Bar, R. 160
prophylactic laminitis treatment which included enoxaparin
sodium (Clexane Forte, Sanof Winthrop industries, France,
0.4 mg/kg BW, SC, SID, four treatments) and ice packs on
all distal limbs for 72 hours. In addition, the thoracic cavity
drained and lavaged once a day for two consecutive days,
via the ventral thoracostomy tube, using 2L of warm saline
and instilling 250 mg imipenem-cilastin sodium (Primaxin
®
,
Merck Sharp & Dohme Corp., NJ, USA), into the thoracic
cavity following drainage of all the lavage fuids. Te ven-
tral thoracostomy tube was removed after the second lavage,
since only clear fuids were returned. Te dorsal thoracostomy
tube was removed after four days when repeated radiographs
showed properly infated lungs and well aligned rib fractures.
One week post-operatively the flly had an elevated body
temperature (39.1°C) and leukocytosis (WBC - 17×10
9
/L,
reference 5.40 - 14.3×10
9
/L). Te primary wound was clearly
infected, sutures were starting to open and pus was oozing
out. At that point, the wound was opened to the level of the
muscle layer, the Jackson-Pratt drain was removed and sent
for culture and sensitivity and the wound was debrided and
thoroughly lavaged. Finally, a Penrose drain was placed at the
most depended point and the systemic antibiotics (penicil-
lin and gentamycin) were changed to cefquinom sulphate
(Cobactan 25%, Intervet international, Germany, 1 mg/kg
BW, IM, BID) coupled with metronidazole at the previously
described dosage. Te above described treatment continued
for fve days, during which the flly’s temperature returned
to normal level and her condition gradually improved.
Staphylococcus epidermidis was cultured from the wound,
which was resistant to most antibiotics with the exception
of vacomycin and oxytetracycline. Tus, the flly’s antibiotic
regimen (cefquinom and metronidazole) was changed to
oxytetracyclin (Terranycin
®,
Pfzer, NY, USA) at a loading
dose of 9 mg/kg BW, IV, BID and continuing with 6 mg/kg
BW, IV, BID for an additional fourteen days.
After two weeks of hospitalization and gradually decreas-
ing intensity of care, the flly was discharged home, in good
clinical condition. Owner was instructed to continue antibi-
otic therapy, using preplaced extended use intravenous cath-
eter (Milacath
®
, MILA International, INC, Erlanger, KY,
USA) inserted in the right jugular vein, for an additional of
ten days, as well as performing daily cleaning of the wound.
Outcome
Follow-up information obtained approximately two weeks
following discharge indicated that the flly was doing well,
the wound was healing nicely and minimal daily exercise was
initiated. Tree years after discharge, the referring veterinar-
ian reported that the flly was back to work showing no signs
of exercise intolerance or any other clinical signs.
DISCUSSION
Penetrating thoracic injury represents an important cause
of morbidity and mortality in horses (5). Quick, thorough
assessment followed by prompt emergency management,
temporary or permanent wound closure and restoring nega-
tive pressure within the thorax are the vital steps required for
successful outcome of these patients (1, 4, 5, 6). In the present
case, the flly was presented with respiratory distress, shock,
fractured ribs, open pneumothorax and hemothorax. Te flly
was initially stabilized, then went through standing thoracic
surgery and recovered completely.
Figure 4: A post-operative image demonstrating the placement of the
dorsal (red arrow) and ventral thoracostomy (red arrow head) tubes.
A Heimlich valve is shown connected to the dorsal tube (blue arrow).
A container is attached at the end of the Jackson – Pratt Drain (blue
arrow head)
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (3)  September 2014 161 Toracic injury in a flly
In the horse, the two sides of the pleural cavity often com-
municate through a small fenestration in the caudal medias-
tinum (7), increasing the risk for unilateral open pneumotho-
rax to become a life threatening bilateral pneumothorax (2).
It is however, unclear how often do both sides of the equine
thoracic cavity indeed communicate. In one study, healthy
adult horses, went through unilateral standing thoracoscopy,
and none of the horses developed any respiratory distress (8).
Other authors assume frequent communication between the
thoracic sides and relay the clinical phenomenon of unilat-
eral pneumothorax to occlusion of the communication by
exudates (2). In our case, the flly sufered from hemothorax,
which could have occluded the communicating orifces and
may explain the occurrence of unilateral pneumothorax.
Pneumothorax can be classifed as; open, closed and ten-
sion (1, 2, 5, 6, 9, 10). Our flly sufered from a unilateral open
pneumothorax which was treated by primary wound closure
accompanied by placing a dorsal thoracostomy tube, con-
nected to a Heimlich valve, which was used to evacuate air
from the thorax. Te use of a one-way valve for continuous
air evacuation, or a Heimlich valve, decreases the chance for
recurring pneumothorax (11).
Hemothorax in the present case was caused both, from
an intercostal artery and from pulmonary parenchymal lac-
eration. In the case presented here, serial laboratory results
showed relatively low PCV (PCV = 25%) and TS (TS –
4.9g/dL) but stable over time, despite active bleeding.
Nevertheless, the flly was weak; showing signs of shock and
therefore received three liters of fresh whole blood from a
cross matched donor. Moreover, hemostasis was achieved
through wound closure and subsequent pulmonary re-infa-
tion, which has been proven to be sufcient to stop bleeding
from low pressure blood vessels (12).
In a previous study, it was stated that blood in the thorax
associated with penetrating trauma should be removed, as
it is an ideal medium for bacteria and it may facilitate the
development of constrictive fbrothorax (12). Blood evacu-
ation, in the present case, was facilitated by placing a ven-
tral thoracostomy tube. Furthermore, complete evacuation
and cleansing of the thoracic cavity was achieved by intra-
thoracic lavage. We believe that the thoracic lavage aided
in evacuating the hemothorax and contributed to the flly’s
rapid and complete recovery.
Fractured ribs are commonly associated with thoracic
trauma (5). In the adult horse, it is accepted that simple
rib fractures can be managed by strict confnement for 4-6
weeks and proper analgesia (2, 4, 5). In the present case, two
ribs sufered simple fractures, which were stabilized using
cerclage wire. Recently, rib fractures in foals, were repaired
successfully by nylon strands tightened using a tension de-
vice, reconstruction plates, and cable ties (13, 14, 15), these
methods may be considered; in adult horses as well. Te third
rib was shattered, leaving sharp ends and fragments, which
were smoothened and removed respectively.
Pleuritis and pleuropneumonia are common complica-
tions of penetrating thoracic trauma. Moreover, it is accepted
that horses that do develop these complication have a poor
prognosis for survival (2, 4, 6). Terefore, in the case present-
ed here, the flly received comprehensive therapy; including
broad-spectrum antimicrobials (penicillin, gentamycin and
metronidazole), NSAID’s (funixin meglumine), accumulat-
ed blood was evacuated from the thorax and thoracic lavage
using sterile saline solution was performed. Furthermore,
at the conclusion of each thoracic lavage, an intra-thoracic
potent single agent broad-spectrum antimicrobial agent
(imipenem-cilastin sodium) was infused. We frmly believe
that the intensive post-operative therapy was instrumental
to avoiding these potentially fatal complications.
In the present case, the only setback encountered was
wound infection and dehiscence of the superfcial tissue lay-
ers. It seemed probable that a highly resistant S. epidermitis
that was cultured from the wound, was a nosocomial infec-
tion; since these bacteria commonly cause secondary wound
infection in hospitalized patients (16).
In the current case, the entire surgical procedure was per-
formed under standing sedation; and local anesthesia. Te
decision not to induce general anesthesia, was based upon
the favorable response of the flly to initial stabilization, the
left lung seemed to be functioning well, and the fact that
the flly’s condition did not appear to deteriorate. Tere is
a considerable debate regarding the use of general anesthe-
sia versus standing sedation when treating thoracic injuries
in the horse. When selecting the appropriate type of anes-
thesia for treating penetrating thoracic injuries, it must be
taken into consideration the patient status, response to initial
treatment, location and extent of the injury and the need for
intra-thoracic exploration and for aggressive thoracic lavage
(17, 18, 2). Treatment of penetrating thoracic injuries in a
sedated, standing horses has been previously described (2).
Our report describes a flly with an extensive penetrating
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (3)  September 2014 Bar, R. 162
thoracic injury, multiple rib fractures, and a unilateral open
hemo-pneumothorax treated successfully using standing se-
dation and local anesthesia.
In summary, this case describes surgical treatment com-
bined with aggressive post-operative medical management
of a severe penetrating thoracic trauma that resulted in suc-
cessful long-term outcome.
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Case Reports