In horses, very uncommon, but if dx, same principles apply
Fibrin bridges within 3 days between visceral and parietal pericardial surfaces
Minimal to no separation between epicardium & pericardium
Transcript of "Thoracotomy in Cattle & Horses"
RIB RESECTIONINDICATIONS & PROCEDURE Dane Tatarniuk, DVM
Question 1 What are the two most common indications for rib resection?
Question 1 What are the two most common indications for rib resection? Pericarditis Pleuritis / Pleuropneumonia Pericarditismore common indication in bovine Pleuritis more common indication in equine
Pericarditis Etiology Traumatic reticulitis 10cm between reticulum & pericardium Wire, nails, etc. Pointed objects 5 to 14cm in length Trauma to external chest Cardiac neoplasia Lymphoma
Pericarditis Pathophysiology Bacteria inoculation septic inflammation increased permeability fluid exudation influx neutrophils & fibrin Fibrin bridges within 3 days Collagen replaces fibrin by day 6 Extensive fibrosis by 1 month Constrictive & restrictive pericarditis
Question 2 Do cattle have complete or incomplete mediastinum?
Question 2 Do cattle have complete or incomplete mediastinum? Complete Complete mediastinum Only lung on affected side collapses following thoracotomy Other lung unaffected Respiration usually stays normal Horses Incomplete mediastinum Walled off – then OK
Pericarditis Pericardiocentesis Higher risk Caudal to left elbow, sternum to mid-chest Tie left front forward 18 gauge, 6 inch needle Slowly advance needle Watch for needle to move synchronous with heart beat Aspirate blood – back up Collect fluid for cytology, culture Rumen bacteria
Pericarditis Percutaneous pericardial drain Earlier stages of pericarditis (mostly fluid, little fibrin) Large bore sterile chest tube Similar insertion as for pericardiocentesis Egress fluid continuously Ingress lavage daily Pull tube once fluid flushes clear
Thoracotomy Standing, local lidocaine block Incision over 5th or 6th rib 6th rib Preferred - posterior to shoulder 5th rib Adductionof limb during movement Subcutaneous air under forearm, scapula More prone to cellulitis
Thoracotomy Incision started at costo-chondral junction Extend dorsally 20cm Lower than CC junction Lateral thoracic artery & vein Overlying thoracic muscles incised Dorsally Latissimus dorsi muscle Serratus ventralis muscle Ventrally Pectoralis profundus muscle Aponeurosis of obliquus externus abdominis muscle
Thoracotomy Periosteum incised by scalpel Periosteum retracted cranially & caudally with periosteal elevators
Thoracotomy Gigli wire placed 18cm above CC junction Transect Rib wide and thin Disarticulate rib at CC junction
Thoracotomy Incise pleura Carefully Exteriorize pericardium and suture to skin edge Same principle as rumenostomy Can drain pericardial fluid with needle, suction Incise pericardial sac Manually remove fibrin, clots Lavage sac liberally with saline Leave open or close with drain
Thoracotomy Post-operative Cover thoracotomy site with sterile towel or combine roll Held in place with umbilical tape Broad spectrum antibiotics Incision examined, flushed daily Wound kept open as long as fetid material egresses Can take wound up to 1 month to close
Prognosis Cattle 15% survival for pericarditis 71% survival for pleuritis Horses 88% survived surgery 46% returned to intended use