Ch 104 Thoracic wall Flashcards

Question

What is a “step” sign on TFAST?

Answer 1

Indicates a discontinuity of the parietal pleura. Can signify IC muscle tear or rib fracture

Answer 2

Bite wounds > All those with rib fractures, pulm contusion or pneumothorax (according to a study) Ongoing haemorrhage, pneumothorax or sepsis are indications for surgical exploration

Answer 3

Basket-weave pattern

Answer 4

- current thought is that respiratory problems in patients with flail chest are most commonly from underlying pulmonary trauma rather than the presence of the flail segment - no significant difference in outcome between stabilized and unstabilized cases - percutaneous fixation of the ribs within the flail segment to an external brace - around the ribs within the flail segment and at least one rib cranial and caudal to the flail segment

Answer 5

Chondrosarcoma OSA FSA Other spindle cell tumours (haemangiopericytoma, PNST, Schwannoma) HSA infrequent MCT

Answer 6

- Most thoracic wall tumors are malignant - rom the ribs are immobile and usually firm - survival times after thoracic wall tumor removal vary greatly according to tumor type - obvious mass or may develop signs of respiratory compromise - sequele > vena cava compression, chylothorax, lameness - ultrasound - CT provides cross-sectional information that allows anatomic localization and better evaluation of the nature and extent of the pathologic process - biopsy should be performed - Surgical resection should be considered for all STS and chondrosarcomas because of their relatively low metastatic rate - OSA > palliation of pain and pleural effusion +/- chemo

Answer 7

- median of 17 weeks for osteosarcoma - 250 weeks for chondrosarcoma

Answer 8

3 cm * including at least one unaffected rib cranial and caudal to the lesion.

Answer 9

- Cutaneous and subcutaneous tumors that do not involve the ribs or intercostal muscles may be resected with a deep margin by excising the layered thoracic musculature - If the tumor involves deep structures only, with a fascial layer between it and the skin, it may be possible to preserve skin to simplify wound closure. - thorocotomy for inspection of the intrathoracic component to confirm that the proposed excision will, indeed, provide adequate surgical margins -

Answer 10

* Deep pectoral muscle flaps * Sanwiches of mesh and PMMA * Kiel bone

Answer 11

main goals - restore integrity of the pleural space (negative pressure) - ensure sufficient rigidity of the thoracic wall - ensure epithelial coverage - Experimental and clinical studies have shown that a small section of flail chest does not adversely affect ventilatory function in dog - 4 ribs > reconstructed using readily available tissues - Larger or defects of the sternum or diaphragm > planning to avoid flail chest, mediastinal shift, and undue postoperative pain

Answer 12

* Latissimus dorsi * External abdominal oblique * Transversus abdominis * Diaphragmatic advancement (ribs 8-13) (may require caudal lung lobectomy)

Answer 13

* Polypropylene mesh * PTFE mesh/sheet ($$, strong and occlusive) * Polyglactin mesh (absorbable, good for infected sites) * Porcine SIS Infection rates with polypropylene mesh 0-5.7%. Can be minimised by covering with well vascularised tissue (omentum, muscle)

Answer 14

- Thoracic wall defects arising from resection of the caudal ribs (8 through 13) are best reconstructed by ipsilateral diaphragmatic advancement - Occasionally, animals may require caudal lung lobectomy with diaphragmatic advancement because of a reduced pleural cavity size - costochondral junctions > closed with a latissimus dorsi muscle flap - dorsi muscle is transected at its origin along the vertebral spinous processes, - skin: advancement flaps, or H-plasty.

Answer 15

- Prolene mesh resists stretching in all directions - PTFE is strong, and the sheets (as opposed to the mesh) provide an occlusive layer that allows maintenance of an airtight seal. - polyglactin mesh is absorbable and therefore indicated for infected or contaminated sites. - associated with persistent postimplantation wound infection, low rate in dogs - Infection rates are reduced in dogs and humans if the mesh is covered by well-vascularized tissue - polypropylene mesh can first be closed with porcine small intestinal > pleural seal and protect organs from mesh

Answer 16

- if pneumothorax or pleural effusion is of concern, a thoracic drain is maintained for at least 12 hours after surgery. - Pleural effusion is a major complication of thoracic wall resection and reconstruction - patients should be carefully monitored for respiratory and cardiovascular sequelae - Abnormal function, lung atelectasis, hypoventilation from pain or medications may all result in abnormal blood gas values - may require Oxygen supplementation - Patients with hypotension should be evaluated for underlying causes, such as hemorrhage, hypovolemia - infiltrative blocks of bupivacaine administered in the intercostal spaces of the surgery site - Systemic agents include intermittent bolus or constant rate infusions of opioids

Answer 17

* Suctioned every hour until 3 consecutive negative results have been obtained. Then every 4 hours for 12 hours * Pleural effusion after reconstruction within forst 48hr and then declines sharply within 4-5 days

Answer 18

restrospective study 65 Ten minor (15.3%) and four major (6.2%) complications occurred. JP significantly less likely to have complications than thoracostomy drains There were no differences when comparing all three drains individually. JP drains and GW drains can be considered as an alternative to traditional TRO thoracostomy drains.

Answer 19

Parasternal rib disarticulation at the sternocostal joint. 93 dogs. 89.2% survived to discharge Thoracostomy tube duration correlated with survival complications and short-term outcomes comparable to traditional median sternotomy approach Closure > nonabsorbable monofilament, periosteum of the rib to the sternocostal cartilage. 32.3% postoperative complications > FL lameness (3.2%) major no reported hemorrhage (7.5%) had incisional complications (fewer closure-related complications than the traditional MS approach)

Answer 20

primary rib tumours in cats: eight, 3 hemangiosarcoma, 2 osteosarcoma and 1 chondrosarcoma, osteochondroma and osteoma 3 minor and 1 major complication post-operative period. Wide surgical excision and adjuvant chemotherapy > HAS and OSA > prognosis remains guarded. Prognosis appears to be fair for the other tumour types. chest wall reconstruction: polypropylene mesh + latissimus dorsi / pectoral muscles flap and ometalization paradoxical rep movement > inappropriate tensioning of the muscle flap created preoperative incisional biopsy should be performed no clear benefit for chemo

Answer 21

Biomechanical comparison: polydioxanone suture, stainless steel bone staples and nitinol bone staples NS and SS staple repairs required application of significantly greater force than PDS across all displacement criteria results imply that bone staples can be considered as an alternative surgical method for median sternotomy closure in dogs. 346 N during coughing in 30kg greyhound > capable of causing 1- and 2- mm displacement PDS group vs none in bone staple groups.

Answer 22

Biomechanical comparison suture tape and orthopedic wire for MS No differences displacement, yield load, maximum load, implant failure between the groups. wire construct was stiffer than the suture tape Conclusion: Suture tape was biomechanically similar to orthopedic wire need to test in clinical cases.

Answer 23

retrospective Comparison orthopedic wire or suture or MS in 263 dogs closure-related complications (14.1%), 20 wire and 17 suture 10 dogs > revision surgery, nine due to closure-related only factor associated with increased risk of closure-related complications was dog size likelihood of developing a closure-related complication was equivalent between sutures and wires, independent of dog size higher proportion of complications seen in larger dogs (≥20 kg). infection rate of 2.7% biomechanical study: (4 metric/1 USP PDS) could provide as effective closure of the sternum as orthopedic wire (12 gauge) in 12 greyhounds.

Answer 24

Presence of ⩾3 radiographic lesions should raise suspicion of a penetrating injury and may be suggestive of injury requiring a greater level of intervention. The treating veterinarian should have a high index of suspicion for penetrating injury and be prepared in case thoracic exploratory surgery is necessary, particularly in the presence of pseudo-flail chest, pneumothorax or ⩾3 radiographic lesions. Pneumothorax was the most common radiographic finding (11/18).

Answer 25

Retrospective Crimped monofilament nylon leader for MS in 10 dogs Postoperative infection > 1 dog successfully closed with a low complication rate. Stainless-steel wire > high tensile strength and stiffness, low tissue reactivity, and good knot security > poor handling characteristics, with glove perforation Stainless-steel wire fracture was reported in 20% of dogs histopathology > chondral and osteochondral bridging with SSW comparison to fibrous unions with suture closure. biomechanically, MNL is less stiff than SSW and will creep under constant displacement

Answer 26

Prospective. muscle-sparing lateral thoracotomy compared to standard. 28 dogs. Gait was analyzed with a force plate preoperative and 3-daypostoperative SI > 3.1-fold greater after SLT compared with after MSLT Pain scores 1 day > lower after MSLT compared with after SLT postoperative pain and ipsilateral forelimb lameness were reduced by sparing the latissimus dorsi all dogs were lame to some degree postop > muscle transection is not the sole cause of pain.

Answer 27

Retrospective. thoracic dog bite wounds in dogs. 123 Dogs that sustained pseudo-flail chest, rib fracture, or pneumothorax were more likely to undergo exploratory thoracotomy. 25 > exploratory thoracotomy, including lung lobectomy in 12 Nonsurvival more likely > pleural effusion or positive bacterial culture. previous authors have advocated a more conservative approach because of higher mortality rates after thoracotomy

Ch 104 Thoracic wall Flashcards

(52 cards)