Page 153 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery

there is evidence of either adhesion or invasion of the rib Excision of rib tumours with incomplete histological
tumour into adjacent structures, such as the lungs, peri- margins is the most important risk factor for local tumour
VetBooks.ir resected en bloc with the rib tumour (Figures 11.10 and Ehrhart et al., 1995), hence chest wall resection should not
cardium, diaphragm or vertebrae, then these should be
recurrence and survival in both dogs and humans (Pirkey-
be compromised by either the location of the affected
11.11). Adhesions should be excised en bloc rather than
broken down because 57% of tumour-associated adhe-
sions in humans have histological evidence of invasion rib(s) or the number of ribs that require resection.
(Nogueras and Jagelman, 1993). In one series of chest wall Sternal tumours and resections: Sternal resection and
resections for rib tumours in dogs, en bloc partial lung reconstruction presents a greater challenge than rib resec-
lobectomy was reported in 25.6% of dogs and partial peri- tion and reconstruction because of the role of the sternum
cardectomy in 7.7% of dogs (Liptak et al., 2008a). in chest wall stability and the increased risk of compli-
Concurrent resection of any volume of lung is associated cations following sternal reconstruction with standard
with a significantly higher risk of respiratory complications autogenous and prosthetic techniques in dogs (Liptak et
and perioperative mortality in humans (Weyant et al., al., 2008a). Sternal defects should be reconstructed with
2006). However, respiratory complications are rare in dogs auto genous muscle flaps, composite techniques such as
following chest wall resection, and en bloc partial lung prosthetic mesh with either autogenous muscle flaps or
lobectomy is not associated with an increased risk of post- omental pedicle flaps, or more rigid prosthetic techniques
operative complications in dogs (Liptak et al., 2008a). such as mesh–methylmethacrylate sandwiches (Liptak
et al., 2008a).
Number of ribs resected: The maximum number of ribs
that can be safely resected in cats and dogs is unknown. Chest wall reconstruction
Six ribs can be safely resected in dogs without the need
for rigid reconstruction of the thoracic wall. Furthermore, Surgical technique: Primary repair of chest wall defects
the number of ribs resected does not significantly increase involves suturing of the ribs without supplemental recon-
the risk of postoperative complications (Pirkey-Ehrhart et struction and is only possible following resection of a
al., 1995; Liptak et al., 2008a). small number of ribs (Pirkey-Ehrhart et al., 1995). Primary
suturing is acceptable if wide excision of the tumour is
possible with minimal rib resection, but wide excision
of the tumour should not be compromised because of
concerns regarding closure. Primary repair of chest wall
defects is rarely possible because of their large size
(Figures 11.12–11.14). As a result, a number of autogenous
and prosthetic techniques have been reported for the
reconstruction of chest wall defects. The aim of chest wall
reconstruction is to fill the defect and reduce dead space,
establish an airtight seal of the pleural cavity and provide
sufficient rigidity to prevent respiratory compromise and
protect intrathoracic structures.

Rib tumours can either invade or be adherent to adjacent
11.10
structures such as lung lobes, pericardium or diaphragm. In
this dog with a rib osteosarcoma (OSA), the tumour has invaded the
diaphragm (D) (arrowed). The diaphragm should be excised with 3 cm
margins en bloc with the rib tumour.

A typical chest wall defect following resection of a primary rib
In this dog with a primary rib chondrosarcoma (CSA), a lung 11.12 osteosarcoma ith five ribs. These defects are too large for
11.11
lobe (L) has adhered to the tumour (arrowed). A lung primary repair and require reconstruction with autogenous and/or
lobectomy was performed with a thoracoabdominal stapler en bloc with prosthetic techni ues. Ca caudal e tent of the chest all defect
the rib tumour to minimize the risk of incomplete tumour excision and Cr cranial e tent of the chest all defect L latissimus dorsi muscle
local tumour recurrence. V = ventral extent of the chest wall defect.

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