7.2 Hemi-glossectomy + Free Flap Flashcards
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
- airway
potentially difficult airway
detailed airway assessment
discussion of potential of AFOI / Awake trache - Breathing
Type of cancer a/w smoking history
any respiratory co morbs? current smoker
encourage them to quit pre op - Circulation
What side will they take radial flap from - no iv access / arterial lines here
patients underlying functional status
echo / ecg pre op
- pain - current pain issues from ca - opiate requirement?
- endocrine - 6. Fluids - often prolonged surgery may require cvc / co monitoring to guide fluid tx
7.
b) List the benefits of a free flap reconstruction. (2 marks)
Can do recon on an area poorly amenable to rotated flap
Provides surgeon more freedom with flap and insertion
c) What are the causes of flap failure and how may they be prevented in the perioperative period?
(8 marks)
- Ischaemic time of flap
if prolonged time before reconnection to blood supply may become ischaemic
Expedited reconnection to blood supply - hypotension
ensure adequate bp maintain - Vasoconstriction
- low dose vasopressor if required - infection
- prophylactic antibiotics and strict sterility - Thrombosis
VTE prophlaxis
regular assessment by nursing and surgical team - Necrosis - ensure no pressure and free drainage of flap
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
A+B
Airway:
» May be a difficult airway due to tumour and any preceding radiotherapy.
» Consideration needs to be given to airway plan – may include awake
fibreoptic intubation or awake tracheostomy depending on assessment.
Respiratory:
» Likely to be smoker: assess for evidence of smoking-related lung
disease.
» Smoking increases risk of flap failure.
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
C
Cardiovascular:
» Likely to be a smoker: assess for evidence of ischaemic heart disease.
» Smoking-related peripheral vascular disease may increase risk of flap failure.
» Likely to have a history of high alcohol intake: risk of arrhythmia, dilated
cardiomyopathy.
» Consider the cardiovascular effects of preceding chemotherapy.
» Vascular access site will be determined by the donor site – ensure
confirmation of planned donor site with surgeon before any cannulations.
c) What are the causes of flap failure and how may they be prevented in the perioperative period?
(8 marks)
- Ischaemic time of flap
if prolonged time before reconnection to blood supply may become ischaemic
Expedited reconnection to blood supply - hypotension
ensure adequate bp maintain - Vasoconstriction
- low dose vasopressor if required - infection
- prophylactic antibiotics and strict sterility - Thrombosis
VTE prophlaxis
regular assessment by nursing and surgical team - Necrosis - ensure no pressure and free drainage of flap
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
D
+ GI
Neurological:
» If ongoing high alcohol intake, consider the possibility of withdrawal whilst
inpatient and treat appropriately.
Gastrointestinal:
» Risk of poor nutrition associated with high alcohol intake, oral cancer,
chemotherapy. Increases risk of poor wound healing and flap failure.
> > Consideration of preoperative PEG placement to optimise perioperative nutrition.
a) Which specific factors must
the anaesthetist consider when
assessing this patient prior to
surgery? (10 marks)
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
D
+ GI
Neurological:
» If ongoing high alcohol intake, consider the possibility of withdrawal whilst
inpatient and treat appropriately.
Gastrointestinal:
» Risk of poor nutrition associated with high alcohol intake, oral cancer,
chemotherapy. Increases risk of poor wound healing and flap failure.
> > Consideration of preoperative PEG placement to optimise perioperative nutrition.
a) Which specific factors must
the anaesthetist consider when
assessing this patient prior to
surgery? (10 marks)
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
Haematological:
» Risk of anaemia: associated with high alcohol intake, malnourishment or
chronic disease. Impairs wound healing and flap survival.
» Prolonged surgery: mechanical deep vein thrombosis prophylaxis.
Infection, immune:
» Comorbidities increase propensity to infection: assess for possibility of
e.g. respiratory infection preoperatively.
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
Haematological:
Infection, immune:
Haematological:
» Risk of anaemia: associated with high alcohol intake, malnourishment or chronic disease. Impairs wound healing and flap survival.
> > Prolonged surgery: mechanical deep vein thrombosis prophylaxis.
Infection, immune:
» Comorbidities increase propensity to infection: assess for possibility of
e.g. respiratory infection preoperatively.
A 54-year-old patient with base of tongue cancer presents for a hemiglossectomy and radial forearm free flap reconstruction.
a) Which specific factors must the anaesthetist consider when assessing this patient prior to surgery?
(10 marks)
Cutaneomusculoskeletal:
Metabolic:
Psychological:
Cutaneomusculoskeletal:
» Often very prolonged surgery and possibly malnourished, underweight
patient. Meticulous attention to positioning and protection.
Metabolic:
» Prolonged surgery – warming mattress, warmed fluids and core and surface temperature monitoring required.
Psychological:
> > Patient anxiety due to potentially life-changing surgery may need pharmacological management
b) List the benefits of a free flap
reconstruction. (2 marks)
What are the benefits of a free flap reconstruction? Consider what the
alternatives are, and it helps to organise your thoughts. Without going
into too much plastic-surgical detail, an area of body that has had cancer
removed could be covered by a graft (skin and subcutaneous tissues that
are taken from elsewhere in the body and rely on development of vascular
supply from the recipient site to survive) or a flap. The flap can be local
(moving a chunk of tissue to cover a defect locally, taking its blood supply
with it), pedicled (excising an area of tissue and moving it to some distant
part of the body whilst retaining a pedicle through which the original blood
supply still flows, for example a transverse rectus abdominis muscle, or
TRAM, flap) and finally a free flap (where tissue is completely removed from
the donor site and its blood vessels are anastomosed at the recipient site).
You can visualise that a graft of skin and subcutaneous tissues alone will
not give the functional or cosmetic result of a flap in this case, nor will it
necessarily develop sufficient blood supply to survive when covering such
a large area. There are no suitable nearby donor sites that could provide a
local or pedicled flap, especially as the use of bone in the reconstruction that
this patient will have is so critical to the functional and cosmetic outcome.
b) List the benefits of a free flap
reconstruction. (2 marks)
Better cosmetic outcome than a graft.
» Better functional outcome than graft: bone used to reconstruct a functioning jaw into which dental implants can ultimately be inserted.
> > Lack of suitable local donor sites for local or pedicled flap.
> > Better coverage than a graft for large and deep defects.
> > Better healing and vascularisation than a graft.
> > Possibility of retaining innervation as the whole neurovascular bundle can be reanastomosed.
> > Better coverage of delicate underlying structures than a graft.
c) What are the causes of flap failure and how may they be prevented in the perioperative period?
(8 marks)
- Inadequate perfusion
- Flap oedema
- Poor wound healing
- Poor oxygen delivery
- Anastomosis failure
Inadequate
perfusion
Blood flow = delat P pi r4 /8nl
R, radius of vessels:
• Maintain normothermia with active warming, and maintain core:peripheral temperature gradient less than 1°C. Avoid postoperative shivering.
- Adequate analgesia: transplanted arteries still respond to catecholamines. Consideration of regional anaesthesia.
- Use flow-directed therapy to optimise fluid management and to avoid inappropriate use of vasoconstrictors.
• Arterial thrombosis: may be triggered by inflammatory reaction due to reperfusion after prolonged ischaemic time.
Avoid excessive ischaemic
time.
May need anticoagulation to avoid arterial thrombosis.
ΔP, pressure gradient along vessels:
• Maintain blood pressure. Intra-arterial blood pressure monitoring, cardiac output monitoring, keep cardiac output high.
• Avoid extramural pressure on arteries: ensure dressings not tight, drains
utilised to avoid haematoma.
• Avoid poor venous drainage due to thrombosis. Anticoagulation may be
required. Maintain normothermia.
• Avoid inadequate venous drainage due to external compression.
η, viscosity of blood:
• Aim for haematocrit of 0.3 as this offers optimum balance between
oxygen delivery and blood flow.
