1887

Thoracic wall anatomy and surgical approaches

image of Thoracic wall anatomy and surgical approaches
GBP
Online Access: GBP25.00 + VAT
BSAVA Library Pass Buy a pass

Abstract

Surgery is required to manage pathology of the thoracic wall, including neoplasia and trauma, and to access the thoracic cavity. Knowledge of anatomy, thorough patient assessment, stabilization and careful attention to anaesthesia and analgesia regimens are essential. This chapter covers anatomy, anaesthetic management, analgesia and postoperative care, and surgical approaches to a range of presentations. : Lateral or intercostal thoracotomy. Video Clip : Flail chest in a dog. If you have purchased the print edition of the book, there is a code at the end of this chapter which enables you to access the online chapter and video.

Preview this chapter:
Loading full text...

Full text loading...

/content/chapter/10.22233/9781910443347.chap11

Figures

Image of 11.1
11.1 Skeletal anatomy of the thorax. (a) The left thorax, demonstrating the positions of incisions for lateral thoracotomy required to perform, for example, patent ductus arteriosus ligation (fourth), lung lobectomy or pericardectomy (fifth) or thoracic duct ligation (ninth; left in the cat, right in the dog). (b) Anatomy of the sternum, showing the extent of sternotomy incisions for procedures such as resection of a cranial (Cr) or caudal (Ca) mediastinal mass. (Redrawn after Evans, 1993) Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 11.2
11.2 Diagram showing the external muscular anatomy of the thoracic wall relevant to performing a lateral thoracotomy. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 11.4
11.4 Intercostal thoracotomy closure using a transcostal technique. (a) Holes are drilled into the mid-body of the caudal rib with a small intramedullary pin or large Kirschner wire. Note that the underlying lungs are being protected from iatrogenic trauma with a moistened laparotomy sponge. (b) Once the hole is drilled in the caudal rib, suture material is passed around the cranial rib and through the hole in the caudal rib. Following preplacement of the transcostal sutures, the sutures are used to approximate the ribs by an assistant while the surgeon ties the knots.
Image of 11.5
11.5 The steps involved in performing a median sternotomy. (a) A skin incision is made along the ventral midline over the length of the sternum. The incision is continued through the subcutaneous tissues to expose the pectoral muscles (PM). (b) The pectoral muscles (PM) are sharply incised along the ventral midline. (c) An oscillating saw is used to perform the median sternotomy along the ventral midline of the sternum. Care should be taken to avoid iatrogenic damage to the underlying lungs and heart during the median sternotomy by limiting penetration of the saw blade. (d) In this dog, a median sternotomy has been performed to allow resection of a cranial mediastinal thymoma (TH). The edges of the intercostal thoracotomy are protected with moistened laparotomy sponges (LS) and the ribs are retracted with Finochietto rib retractors (FRR) to maximize exposure of the thoracic cavity. (e) The median sternotomy can be closed with a figure-of-eight suture pattern using heavy-gauge suture material (5 metric (2 USP) polypropylene). Suture closure of the median sternotomy should only be performed in cats and small dogs, because suture closure in larger breeds of dogs results in inferior sternal stability and osseous healing of the median sternotomy when compared with wire closure (Pelsue ., 2002). (f) Alternatively, the median sternotomy can be closed with orthopaedic wire; in this case an individual cruciate pattern across each costosternal junction is used. (g) The wires are preplaced and then tightened. (h) Following closure of the sternum, the pectoral muscles, subcutaneous tissue and skin are closed routinely. (i) The thoracostomy tube is secured with a Chinese fingertrap suture pattern.
Image of 11.6
11.6 Short-term complications, such as this wound infection, are reported in up to 40% of cases in dogs following median sternotomy.
Image of 11.7
11.7 Thoracic wall resection in a dog. (a) When resecting chest wall masses, all contiguous tissue should be excised with the chest wall mass, including biopsy sites (BS). LD = latissimus dorsi muscle. (b) The biopsy tract excision is continued deeply through all soft tissues. The latissimus dorsi muscle was able to be preserved in this case for autogenous reconstruction of the chest wall defect, but these soft tissue structures should be excised if required to achieve adequate surgical margins for complete resection of the tumour. (c) Once the soft tissue resection has been performed to the level of the ribs, an intercostal thoracotomy (*) is performed one rib caudal to the tumour (as determined from preoperative imaging). (d) Visualization of the rib tumour (arrowed) permits visual assessment of the mass, determination of ventral and dorsal surgical margins in combination with preoperative imaging, and preparation of the ribs for ostectomy. (e) The intercostal vessels are ligated on the dorsal aspect of each rib to be resected either individually or, as depicted, with heavy-gauge circumcostal ligatures (arrowed). (f) The ribs are ostectomized immediately ventral to the ligated intercostal vessels with bone cutters or power saws. (g) The ribs are progressively ostectomized along their dorsal borders until the cranial aspect of the excision is identified, one rib cranial to the rib tumour. The excision can then be continued either ventrally or with the cranial intercostal thoracotomy.
Image of 11.8
11.8 A partial sternectomy (S) may be required to achieve adequate ventral margins for tumours located at or ventral to the costochondral junction (arrowed). The costosternal junction should provide a barrier to tumour extension, but part of the sternum should be excised to ensure complete surgical excision.
Image of 11.9
11.9 Resection of the entire affected rib(s) has been recommended because of the possibility of intramedullary extension of the rib tumour and resultant incomplete excision if margins were based on the palpable limits of the tumour.
Image of 11.10
11.10 Rib tumours can either invade or be adherent to adjacent 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 with the rib tumour.
Image of 11.11
11.11 In this dog with a primary rib chondrosarcoma (CSA), a lung lobe (L) has adhered to the tumour (arrowed). A lung lobectomy was performed with a thoracoabdominal stapler with the rib tumour to minimize the risk of incomplete tumour excision and local tumour recurrence.
Image of 11.12
11.12 A typical chest wall defect following resection of a primary rib osteosarcoma with five ribs. These defects are too large for primary repair and require reconstruction with autogenous and/or prosthetic techniques. Ca = caudal extent of the chest wall defect; Cr = cranial extent of the chest wall defect; LD = latissimus dorsi muscle; V = ventral extent of the chest wall defect.
Image of 11.13
11.13 A typical chest wall defect following resection of a caudal rib osteosarcoma. Note the exposure of the abdominal cavity. In such cases, the thoracic cavity can be reconstructed by advancing the diaphragm and then the abdominal wall is reconstructed with autogenous and/or prosthetic techniques. D = diaphragm; I = intestines; Li = liver; Lu = lungs; S = spleen.
Image of 11.14
11.14 (a) A large chest wall defect and cutaneous defect following the resection of six ribs for a primary rib chondrosarcoma, including excision of an adhered lung lobe (see Figure 11.11 ) and pericardium. The cutaneous defect was larger than normal because of combined excision of both the biopsy tract and a concurrent grade II mast cell tumour with 3 cm lateral margins. The cutaneous defect was closed primarily. Note the partial sternectomy to achieve adequate ventral margins. (b) A latissimus dorsi muscle flap (LD) can be used to reconstruct chest wall defects resulting from the resection of up to six ribs, but occasionally this muscle flap will not be sufficient to reconstruct the chest wall defect if part of the muscle has been excised with the tumour, if the chest wall defect is not within the arc of rotation of the muscle flap, or if the chest wall defect is too large, such as with this chest wall defect resulting from the excision of a primary rib chondrosarcoma with six ribs and a portion of the latissimus dorsi muscle. (c) If the latissimus dorsi muscle flap (LD) is not sufficient for reconstruction of the entire chest wall defect, then autogenous reconstruction can be supplemented with a prosthetic mesh (PM).
Image of 11.15
11.15 (a) The latissimus dorsi muscle is being prepared. The ventral border (V) is the ventral aspect of the muscle, which borders the edge of the chest wall resection. The caudal border (Ca) has been incised from the 13th rib. Perforating intercostal vessels (arrowed) are ligated or cauterized and transected. (b) Following elevation of the caudal border, the dorsal border of the flap is incised parallel to the ventral border from the head of the 13th rib to the caudal border of the triceps muscle. (c) The latissimus dorsi muscle flap is sutured into the chest wall defect with either an interrupted or a continuous (depicted) suture pattern to the cranial and caudal ribs and ventrally to the pectoral musculature.
Image of 11.16
11.16 (a) A caudal rib tumour has been excised and the chest wall has been reconstructed by advancing the diaphragm. The resultant abdominal wall defect has initially been reconstructed with an omental pedicle graft with the omentum sutured to the edges of the abdominal and chest wall defect. Omentum should not be used for primary reconstruction of chest wall defects. In this case, the omentum will cover the peritoneal aspect of the prosthetic mesh reconstruction of the abdominal and chest wall defect. (b) Reconstruction of the chest and abdominal wall defect is completed by suturing prosthetic mesh into the defect with a simple continuous suture pattern over the omental pedicle graft. The omental pedicle graft should reduce pleural and peritoneal inflammation and promote healing and incorporation of the prosthetic mesh.
Image of 11.17
11.17 (a) The chest and abdominal wall defect resulting from resection of a caudal rib osteosarcoma. Following caudal rib resections, the thoracic cavity can be restored by advancing the diaphragm (D) rather than reconstruction of the chest wall. (b) The free edge of the diaphragm is advanced and sutured to the edge of the chest wall resection with a simple interrupted (depicted) or continuous suture pattern. (c) The diaphragm has been advanced to restore normal thoracic function and physiology. Note the temporary thoracostomy tube (arrowed), which is used to evacuate air and fluid from the thoracic cavity intraoperatively and is removed once negative intrathoracic pressure has been established. The resultant abdominal wall defect is then reconstructed using autogenous and/or prosthetic techniques (see Figure 11.16 ). AB = abdominal cavity; L = lungs.
Image of 11.18
11.18 (a) A chest wall defect following resection of seven ribs (ribs 7–13) for excision of an injection-site sarcoma in a cat. The diaphragm will be advanced to reconstruct the thoracic cavity, but it is likely that diaphragmatic advancement will decrease intrathoracic volume and restrict lung expansion, resulting in hypoxaemia and respiratory distress. In these cases, lobectomy of the caudal lung lobe should be considered. (b) A caudal lung lobectomy is being performed with a thoracoabdominal stapler to permit sufficient intrathoracic volume for normal expansion of the remaining lung lobes following diaphragmatic advancement. (c) Following caudal lung lobectomy, there is sufficient intrathoracic volume for normal expansion of the remaining lung lobes. (d) The diaphragm is being advanced to restore normal thoracic function and physiology. Note the temporary thoracostomy tube, which is used to evacuate air and fluid from the thoracic cavity intraoperatively and is removed once negative intrathoracic pressure has been established. The resultant abdominal wall defect is then reconstructed using autogenous and/or prosthetic techniques (see Figure 11.16 ).
Image of 11.19
11.19 Prosthetic polypropylene (Marlex) mesh has been used to reconstruct a chest wall defect following resection of a primary rib osteosarcoma. The edges of the mesh are doubled over and sutured to the chest wall defect using either an interrupted (depicted) or continuous suture pattern under mild tension.
Image of 11.20
11.20 Distal necrosis of a latissimus dorsi (LD) muscle flap resulting in a chest wall defect (arrowed).
Image of 11.21
11.21 (a) A chest wall defect following resection of a sternal haemangiosarcoma, which included six sternebrae and approximately 50% of the associated six ribs left and right of the sternum. (b) This large chest wall and sternal defect was reconstructed with a prosthetic Marlex mesh because autogenous reconstruction was not possible. However, the large surface area of the lungs in contact with the prosthetic mesh resulted in pleuritis and subsequent pleural effusion. To minimize the risk of this complication, an omental pedicle graft should be considered on the pleural surface of the mesh (see Figure 11.16 ).
Image of 11.22
11.22 Bite wounds to the chest following an attack on a Chihuahua by a larger dog. (a) Lateral thoracic view and (b) dorsoventral view of the thorax. These radiographs of a Chihuahua reveal fracture of the fifth and sixth ribs, pneumothorax and subcutaneous emphysema.
Image of 11.23
11.23 Surgical exploration of thoracic bite wounds in a cat. (a) Minor skin wounds are evident over the thoracic cavity. (b, c) Thoracic radiographs reveal subcutaneous emphysema and mild pneumothorax. (d) Surgical exploration is performed by extending the skin incision dorsoventrally. (e) Intercostal muscle laceration and penetration of the thoracic cavity are revealed. (f) Following lavage, debridement and repair, the wound is closed with a thoracostomy tube and wound drain in place.
Image of 11.24
11.24 Surgical correction of pectus excavatum in a kitten (head is positioned to the left in all images). (a) A lateral thoracic radiograph demonstrating marked dorsal deviation of the caudal sternebrae. (b, c) Placement of transcutaneous sutures around the caudal sternebrae under general anaesthesia following clipping and aseptic preparation of the ventral thorax; ventral traction of the xiphoid cartilage is advised prior to suture placement. (d) A lateral thoracic radiograph obtained 7 days following splint placement demonstrating some improvement in thoracic volume. (e) The kitten with the external splint in place; the splint is padded and wrapped in adhesive dressing material to prevent patient interference.
Image of LD = latissimus dorsi muscle.
LD = latissimus dorsi muscle. LD = latissimus dorsi muscle.
Image of LD = latissimus dorsi muscle; SV = serratus ventralis muscle.
LD = latissimus dorsi muscle; SV = serratus ventralis muscle. LD = latissimus dorsi muscle; SV = serratus ventralis muscle.
Image of CT = cutaneous trunci muscle; LD = latissimus dorsi muscle; SC = scalenus muscle; SV = serratus ventralis muscle.
CT = cutaneous trunci muscle; LD = latissimus dorsi muscle; SC = scalenus muscle; SV = serratus ventralis muscle. CT = cutaneous trunci muscle; LD = latissimus dorsi muscle; SC = scalenus muscle; SV = serratus ventralis muscle.
Image of IC = intercostal muscles; P = pleura; R = rib; SV = serratus ventralis muscle.
IC = intercostal muscles; P = pleura; R = rib; SV = serratus ventralis muscle. IC = intercostal muscles; P = pleura; R = rib; SV = serratus ventralis muscle.
Image of P = pleura; R = rib.
P = pleura; R = rib. P = pleura; R = rib.
Image of L = lungs.
L = lungs. L = lungs.
Image of This dog has lung lobe torsion (LLT).
This dog has lung lobe torsion (LLT). This dog has lung lobe torsion (LLT). FRR = Finochietto rib retractors; LS = laparotomy sponge.
Image of LD = latissimus dorsi muscle; SV = serratus ventralis muscle; TT = thoracostomy tube (arrowed).
LD = latissimus dorsi muscle; SV = serratus ventralis muscle; TT = thoracostomy tube (arrowed). LD = latissimus dorsi muscle; SV = serratus ventralis muscle; TT = thoracostomy tube (arrowed).
Image of Untitled

Supplements

Flail chest in a dog

More like this

/content/chapter/10.22233/9781910443347.chap11
dcterms_title,dcterms_description
-contentType:Journal
5
5
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error