3. Factors
Lesion type: DH, lobectomy,
pericardiotomy, thoracocentesis
Condition of the animal- whether an
early
diagnosed
- withstand extensive
sternotomy(splitting of sternum)/
Intercostal incision should be taken
up
4. factors
Shape and size of thorax
Less capacious- more manipulation-
sternotomy
More capacious – more manipulation-
intercostal is sufficient/ rib split/ rib
resection
5. Techniques of thoracotomy
Intercostal
incision:
• Cranial to the rib –
intercostal vessels are
located caudally
• Extend the incision to
desired length
• A self retaining rib
retractor is used for
adequate exposure of
the intrathoracic
organs.
6. Techniques
• Serratus ventralis
dorsally and external
abdominal obliqus
ventrally – after
incising the facia.
Separate the fibres to
expose external
intercostal muscle.
7. Thoracotomy
• During expiratory
pause the
intercostal m and
pleura – incised-
midway between
the ribs
8. Closure
Chromic
catgut/nylon –
cranial and caudal to
incision- ribs
opposed with towel
clamps
Adv: simple&quick
Dis: insufficient- heart
& great vessels
- Rib fracture when
held with rib
retractor
11. Rib resection
Periosteal
elevator- used
to separate the
periosteum
medially and
laterally
12.
13. Closure
Adv: -good
Series of healing
interrupted
No gap
sutures placed
about 1 cm
apart- lateral Disadv: lot of
and medial skill
periosteal Time consuming
surfaces- cranial Weak point-
and caudal edge absence of rib
of incision
14. Split rib technique
Expose the rib
St. longitudinal
incision- center-
oscillating bone
saw.
Rib is sectioned-
transversely at
either ends- of
primary incision
15. Split rib technique
Adv: maximum
exposure-
without
involvement of
rib retractor
Closure is simple
and quick-
interrupted
stainless steel
wire
16. Disadv:
Dent formation along margins
Sternum splitting incision (Median
sternotomy)
Required for extensive manipulation-
cardiac defects and associated structures
Animal on dorsal recumbency
Skin incision- manubrium to xiphoid
Sternum split- chisel/splitter/ electrical
saw
Don’t sever vessels – either side of
midline
17. Closure
Drill hole in sternabrae- suture with
monofilament nylon
Disadv:
-Postoperative pain- discomfort- depth
of respiration is affected
-Inaccurate apposition
-cardiac output is reduced due to
increased CVP
18. Transabdominal
Other approaches like transabdominal to
repair DH- paracostal incision
Heart worm disease:
-dirofilaria immitis
-Mosquitoes- vectors
-Dog- Primary reservoir
19.
20. Heart worm disease:
-3rdstage larva-
infective- 2-3
weeks- mosquito
mouth parts
-Penetrate skin-
susceptible animal-
3m- immature
worms – reach
right side of heart-
obtain full size-
15-35 cm –
5-6months- live for
>5years- non-
infective
microfilariae
21. Heart worm disease:
-adult worm – pulmonary trunk-less no. in
rt. Ventricle- but found in rt. Atrium and
caudal vena cava in heavily infested
animal
• -severity based on
3. No. of worms and location
4. Host immune response
5. Duration of infection
22. Heart worm disease
Pathogenesis:
Adult worm causes mechanical irritation of
intima and pulmonary arterial walls- CHF
Glomerulonephritis- immune complexes
Pulmonary inflammation and edema
Symptoms: coughing, exercise intolerance,
dyspnoea, cyanosis,wt.loss despite good
appetite hemoptysis, syncope, epistaxis and
ascites
23. Diagnosis:
Antigen detection test
Right ventricular hypertrophy patterns are
seen
Detection of microfilariae in routine blood
examination- failure to detect- doesnot
rule out- presence of microfilariae in
heart- go for concentration technique-
count / ml of blood – 1000 MF=1 adult
worm
5-10% dogs – adult worm- no detectable
circulating MF- eosinophillia is suggestive
24. Mild cases- RG appearance- normal
Angiocardiograms- linear filling defects –
branches of pulmonary artery
Moderate and severe infections- RG-
dilatation of rt. Heart enlargement and
dilatation of pulmonary trunk and its
arteries
25. Splitting
of second heart sound-
suggestive of pulmonary hypertension-
confirmed by direct cardiac catheterization
–measurement of rt.ventricular/
pulmonary artery pressure
Treatment :
1.Melarsomine dihydrochloride @ 2.5 mg/kg
deep i.m.
2.Ivermectin
26. 3. Diethyl carbamazine @ 2.5 mg/ lb
b.w.daily -10 days-1month
4. 6 weeks after-disappearance of
clinical signs- dithiazanine iodide
(dizan)2-3mg/lb orally- kill the
microfilariae-7 days
5. Digoxin and diuretics are given in
CHF
27. 3. Restrict exercise- to reduce thrombosis and
endothelial damage
4. Class IV dirofilariasis – Caval syndrome- vena
cavae syndrome -extreme infestation- sudden
onset- collapse with haemoglobinaria and
respiratory distress
5. Surgical removal –questionable- suggested
that – dogs- with less than 50 worms- can
tolerate chemotherapy
29. Puncture ventriculotomy:
Apply a purse string
suture- pass an
alligator foreceps – in
rt. Ventricle-
repeatedly introduced
and taken out while
hemorrhage is
controlled by purse-
string suture
30. Through median sternotomy-from right
atrium and orifice of tricuspid valve
and caudal vena cava to save the life
of the dog.
31. Rigid / flexible alligator forceps/
intravascular retrieval snare- via
rt. Jugular vein with fluoroscopic
guidance- pass the instrument
untill worms are no longer
retrieved
Fluid therapy