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Thoracotomy Thoracotomy
ThoracotomyThoracotomy
Opening of chest cavityOpening of chest cavityApproaches depends uponApproaches depends upon
1.1. Lesion typeLesion type – DH, lobectomy, pericardiotomy, thoracocentesis – DH, lobectomy, pericardiotomy, thoracocentesis
Approaches depends Approaches depends upon following factors upon following factors
FactorsFactors
Lesion type: DH, lobectomy, Lesion type: DH, lobectomy, pericardiotomy, thoracocentesispericardiotomy, thoracocentesis
Condition of the animal- whether an Condition of the animal- whether an early early diagnoseddiagnosed
- withstand extensive - withstand extensive sternotomy(splitting of sternum)/ sternotomy(splitting of sternum)/ Intercostal incision should be taken Intercostal incision should be taken upup
factorsfactors
Shape and size of thoraxShape and size of thorax
Less capacious- more manipulation- Less capacious- more manipulation- sternotomysternotomy
More capacious – more manipulation- More capacious – more manipulation- intercostal is sufficient/ rib split/ rib intercostal is sufficient/ rib split/ rib resection resection
Techniques of thoracotomyTechniques of thoracotomy Intercostal Intercostal
incision:incision: • Cranial to the rib – Cranial to the rib –
intercostal vessels intercostal vessels are located caudallyare located caudally
• Extend the incision Extend the incision to desired lengthto desired length
• A self retaining rib A self retaining rib retractor is used for retractor is used for adequate exposure adequate exposure of the intrathoracic of the intrathoracic organs.organs.
TechniquesTechniques
• Serratus ventralis Serratus ventralis dorsally and dorsally and external abdominal external abdominal obliqus ventrally – obliqus ventrally – after incising the after incising the facia. Separate the facia. Separate the fibres to expose fibres to expose external intercostal external intercostal muscle.muscle.
Thoracotomy Thoracotomy
• During During expiratory expiratory pause the pause the intercostal m intercostal m and pleura – and pleura – incised- midway incised- midway between the between the ribsribs
Closure Closure Chromic Chromic
catgut/nylon – catgut/nylon – cranial and caudal cranial and caudal to incision- ribs to incision- ribs opposed with opposed with towel clamps towel clamps
Adv: simple&quickAdv: simple&quickDis: insufficient- Dis: insufficient-
heart & great heart & great vesselsvessels
- Rib fracture when - Rib fracture when held with rib held with rib retractorretractor
Rib resectionRib resection
Technique Technique St. incision- over St. incision- over
rib- reflect rib- reflect periosteum- lat. periosteum- lat. and medialand medial
Rib resectionRib resection
Periosteal Periosteal elevator- used elevator- used to separate the to separate the periosteum periosteum medially and medially and laterallylaterally
ClosureClosure Series of Series of
interrupted sutures interrupted sutures placed about 1 cm placed about 1 cm apart- lateral and apart- lateral and medial periosteal medial periosteal surfaces- cranial surfaces- cranial and caudal edge and caudal edge of incisionof incision
Adv: -good Adv: -good healinghealing
No gapNo gap
Disadv: lot of Disadv: lot of skillskill
Time consumingTime consuming Weak point- Weak point-
absence of ribabsence of rib
Split rib technique Split rib technique
Expose the ribExpose the rib St. longitudinal St. longitudinal
incision- center- incision- center- oscillating bone oscillating bone saw.saw.
Rib is sectioned- Rib is sectioned- transversely at transversely at either ends- of either ends- of primary incisionprimary incision
Split rib technique Split rib technique
Adv: maximum Adv: maximum exposure- without exposure- without involvement of involvement of rib retractorrib retractor
Closure is simple Closure is simple and quick- and quick- interrupted interrupted stainless steel stainless steel wire wire
Disadv:Disadv:Dent formation along marginsDent formation along margins
Sternum splitting incision (Median Sternum splitting incision (Median sternotomy)sternotomy)
Required for extensive manipulation-Required for extensive manipulation-cardiac defects and associated structurescardiac defects and associated structures
Animal on dorsal recumbencyAnimal on dorsal recumbency Skin incision- manubrium to xiphoidSkin incision- manubrium to xiphoid Sternum split- chisel/splitter/ electrical Sternum split- chisel/splitter/ electrical
sawsaw Don’t sever vessels – either side of Don’t sever vessels – either side of
midline midline
Closure Closure
Drill hole in sternabrae- suture with Drill hole in sternabrae- suture with monofilament nylonmonofilament nylon
Disadv:Disadv:
-Postoperative pain- discomfort- depth -Postoperative pain- discomfort- depth of respiration is affectedof respiration is affected
-Inaccurate apposition-Inaccurate apposition
-cardiac output is reduced due to -cardiac output is reduced due to increased CVPincreased CVP
Transabdominal Transabdominal
Other approaches like Other approaches like transabdominal to repair DH- transabdominal to repair DH- paracostal incisionparacostal incision
Heart worm disease:Heart worm disease:
-dirofilaria immitis-dirofilaria immitis
-Mosquitoes- vectors-Mosquitoes- vectors
-Dog- Primary reservoir-Dog- Primary reservoir
Heart worm disease:Heart worm disease:
--33rdrd stage larva- stage larva- infective- 2-3 infective- 2-3 weeks- mosquito weeks- mosquito mouth partsmouth parts
-Penetrate skin- -Penetrate skin- susceptible animal- susceptible animal- 3m- immature 3m- immature worms – reach worms – reach right side of heart- right side of heart- obtain full size- 15-obtain full size- 15-35 cm – 5-6months- 35 cm – 5-6months- live for live for >5years- >5years- non- infective non- infective microfilariaemicrofilariae
Heart worm disease:Heart worm disease:
-adult worm – pulmonary trunk-less no. -adult worm – pulmonary trunk-less no. in rt. Ventricle- but found in rt. Atrium in rt. Ventricle- but found in rt. Atrium and caudal vena cava in heavily and caudal vena cava in heavily infested animal infested animal
• -severity based on-severity based on
1.1.No. of worms and location No. of worms and location
2.2.Host immune responseHost immune response
3.3.Duration of infectionDuration of infection
Heart worm diseaseHeart worm diseasePathogenesis:Pathogenesis:Adult worm causes mechanical irritation Adult worm causes mechanical irritation
of intima and pulmonary arterial walls- of intima and pulmonary arterial walls- CHFCHF
Glomerulonephritis- immune complexesGlomerulonephritis- immune complexesPulmonary inflammation and edema Pulmonary inflammation and edema
Symptoms: coughing, exercise Symptoms: coughing, exercise intolerance, dyspnoea, cyanosis,wt.loss intolerance, dyspnoea, cyanosis,wt.loss despite good appetite hemoptysis, despite good appetite hemoptysis, syncope, epistaxis and ascites syncope, epistaxis and ascites
Diagnosis: Diagnosis: Antigen detection testAntigen detection testRight ventricular hypertrophy Right ventricular hypertrophy
patterns are seenpatterns are seenDetection of microfilariae in routine Detection of microfilariae in routine
blood examination- failure to detect- blood examination- failure to detect- doesnot rule out- presence of doesnot rule out- presence of microfilariae in heart- go for microfilariae in heart- go for concentration technique-count / ml concentration technique-count / ml of blood – 1000 MF=1 adult wormof blood – 1000 MF=1 adult worm
5-10% dogs – adult worm- no 5-10% dogs – adult worm- no detectable circulating MF- detectable circulating MF- eosinophillia is suggestiveeosinophillia is suggestive
Mild cases- RG appearance- normalMild cases- RG appearance- normalAngiocardiograms- linear filling Angiocardiograms- linear filling
defects – branches of pulmonary defects – branches of pulmonary arteryartery
Moderate and severe infections- RG- Moderate and severe infections- RG- dilatation of rt. Heart enlargement dilatation of rt. Heart enlargement and dilatation of pulmonary trunk and dilatation of pulmonary trunk and its arteriesand its arteries
Splitting of second heart sound- Splitting of second heart sound- suggestive of pulmonary suggestive of pulmonary hypertension- confirmed by direct hypertension- confirmed by direct cardiac catheterization –cardiac catheterization –measurement of rt.ventricular/ measurement of rt.ventricular/ pulmonary artery pressurepulmonary artery pressure
Treatment : Treatment :
1.Melarsomine dihydrochloride @ 2.5 1.Melarsomine dihydrochloride @ 2.5 mg/kg deep i.m.mg/kg deep i.m.
2.Ivermectin2.Ivermectin
33. Diethyl carbamazine @ 2.5 mg/ . Diethyl carbamazine @ 2.5 mg/ lb b.w.daily -10 days-1monthlb b.w.daily -10 days-1month
4. 6 weeks after-disappearance of 4. 6 weeks after-disappearance of clinical signs- dithiazanine iodide clinical signs- dithiazanine iodide (dizan)2-3mg/lb orally- kill the (dizan)2-3mg/lb orally- kill the microfilariae-7 daysmicrofilariae-7 days
5. Digoxin and diuretics are given 5. Digoxin and diuretics are given in CHFin CHF
3. 3. Restrict exercise- to reduce thrombosis Restrict exercise- to reduce thrombosis and endothelial damage and endothelial damage
4. Class IV dirofilariasis – Caval syndrome- 4. Class IV dirofilariasis – Caval syndrome- vena cavae syndrome -extreme vena cavae syndrome -extreme infestation- sudden onset- collapse with infestation- sudden onset- collapse with haemoglobinaria and respiratory distresshaemoglobinaria and respiratory distress
5. Surgical removal –questionable- 5. Surgical removal –questionable- suggested that – dogs- with less than 50 suggested that – dogs- with less than 50 worms- can tolerate chemotherapyworms- can tolerate chemotherapy
Puncture ventriculotomy:Puncture ventriculotomy:
Puncture ventriculotomy:Puncture ventriculotomy:
Apply a purse string Apply a purse string suture- pass an suture- pass an alligator foreceps – alligator foreceps – in rt. Ventricle- in rt. Ventricle- repeatedly repeatedly introduced and introduced and taken out while taken out while hemorrhage is hemorrhage is controlled by purse- controlled by purse- string suture string suture
Through median sternotomy-from Through median sternotomy-from right atrium and orifice of right atrium and orifice of tricuspid valve and caudal vena tricuspid valve and caudal vena cava to save the life of the dog.cava to save the life of the dog.
Rigid / flexible alligator Rigid / flexible alligator forceps/ intravascular retrieval forceps/ intravascular retrieval snare- via rt. Jugular vein with snare- via rt. Jugular vein with fluoroscopic guidance- pass fluoroscopic guidance- pass the instrument untill worms the instrument untill worms are no longer retrievedare no longer retrieved
Fluid therapy Fluid therapy