Page 23 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

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

• Microfibrillar collagen: Obtained from bovine Halsted’s principles of surgery are at the heart of any suc-
collagen and applied as a powder or sheet to act as a cessful soft tissue procedure. These principles are designed
VetBooks.ir • Thrombin in a gelatin matrix: This is indicated in discomfort, promote rapid wound healing, reduce surgical
scaffold for clot formation.
to reduce surgical morbidity and mortality, minimize patient
surgical procedures (other than ophthalmic) as an
site infection and increase client satisfaction.
adjunct to haemostasis when control of bleeding by
ligature or conventional procedures is ineffective or
impractical. Timing of anaesthesia and surgery
• Cyanoacrylate tissue adhesives: For closure of very Surgical procedures of the upper respiratory tract and
minor wounds and to seal small bleeding sites. thorax are best conducted at the beginning of the day’s
• Phenylephrine and lidocaine: Phenylephrine is a operating list. Careful observation is then possible through-
vasoconstrictor with no beta-blocking action (fewer out the remainder of the day for complications associated
cardiac effects expected than with adrenaline (epin- with the procedure, such as haemorrhage or oedema, that
ephrine), but hypertension and reflex bradycardia are may cause airway obstruction. Similarly, many of the proce-
still possible). Diffuse bleeding from nasal mucosa may dures are not suitable on an outpatient basis or where ade-
respond to wound irrigation with a mixture (0.05–0.1 ml/ quate 24-hour intensive care facilities are not available.
kg in cats; 0.1–0.2 ml/kg in dogs) of 0.25 ml phenyl- Surgery of the external ear canal is generally contaminated
ephrine (1%) and 50 ml lidocaine (2%) (Reiter, 2013). or dirty and should be performed at the end of the day’s list.
Surgery may need to be performed on an emergency
basis for patients that have suffered from marked haemor-
Postoperative care rhage, or those that are severely dyspnoeic or that cannot
eat and drink voluntarily, as soon as the patient has been
Wounds of the head and neck are particularly vulnerable to stabilized. Many disorders causing upper respiratory tract
self-trauma from rubbing and scratching, particularly obstruction are exacerbated by high ambient tempera-
during recovery. Many wounds of the head and neck can- tures. For patients with relatively minor signs, delaying the
not be bandaged satisfactorily without risking asphyxia, procedure until the weather is cooler may be of benefit.
and some device to limit self-trauma (e.g. an Elizabethan However, because of this environmental influence, many
collar) may be required. Adequate analgesia should be animals will present with acute exacerbations of their
ensured in any animal showing self-trauma. disease when the weather is warm, necessitating prompt
Chest bandages may help to protect a thoracotomy intervention at that time.
incision, but care should be taken to avoid placing them
too tightly and restricting breathing. A bandage will also Preparation of the surgeon and team
help to prevent the patient from dislodging a chest tube.
Particular care should be taken to avoid complications Some of the key differences between surgery of the head,
associated with thoracic drains. This includes: neck and thorax and other aspects of soft tissue surgery
are:
• Ensuring that the drain is occluded at two sites
(e.g. gate clamp and bung) • The disease process may affect tissues that do not
• Ensuring that the drain is attached to the patient tolerate surgical manipulation well (e.g. postoperative
(e.g. Chinese finger-trap friction suture) swelling of the laryngeal mucosa)
• Ensuring that the patient cannot remove the drain • Failure of a suture line may have catastrophic
(e.g. Elizabethan collar and bandage). consequences (pneumothorax following pulmonary
lobectomy)
Daily inspection of the wound is important, particularly • The close proximity of important structures, principally
those classified as contaminated or dirty, or those where nerves and vessels (e.g. facial nerve and external ear
drains have been placed. Wound drains may be used in canal)
surgical procedures of the head and neck, either passive • The limited surgical access to some structures (e.g.
(e.g. a Penrose drain placed after sialoadenectomy for a soft palate).
salivary mucocele) or active (e.g. a suction drain placed
after major oncological resection). Therefore, the potential for intraoperative and postoper-
ative complications is relatively high. This tendency should
be reduced by:
Principles of head, neck and • A good anatomical knowledge of the region in question
thoracic surgery • Knowledge of the disease process and how this may
distort the regional anatomy
• A knowledge of the surgical procedure to be performed
Halsted’s principles • A plan for an alternative surgical procedure
• Asepsis and aseptic surgical technique • Gentle atraumatic surgical technique
• Sharp anatomical dissection • Meticulous attention to haemostasis
• Atraumatic tissue handling and surgical technique • Good-quality surgical instruments, appropriate for the
• Removal of devitalized tissue from the surgical purpose
wound • The ability to perform manipulations with minimal
• Precise haemostasis with preservation of blood access, e.g. the ability to hand-tie knots in a cavity
supply to tissues • Careful use of diathermy adjacent to ‘excitable cells’
• Accurate tissue apposition, minimizing tissue dead such as cardiomyocytes and neurons. Avoiding the use
space but without excessive tension on tissues of cutting diathermy in procedures involving the lumen
of the airway.

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