Transcript AIRWAY AND ORAL CAVITY CANCER

Dr.H-Kayalha
Anesthesiologist
Mucositis is a painful inflammation and
ulceration of the mucous membranes of the
digestive tract.
Oral lesions begin as mucosal whitening
followed by the development of erythema
and tissue friability.
Oral mucositis is a relatively common
adverse effect of high-dose
chemotherapy and radiation to the head
and neck.
Mucositis can also occur in the context of
hematopoietic stem cell transplantation.
Chemotherapeutic drugs associated with
mucositis include:
-anthracyclines
-taxanes
-platinum-based compounds
-methotrexate
- fluorouracil.
Mucositis associated with chemotherapy
often begins during the first week of
treatment and typically resolves after
treatment is terminated.
Mucositis associated with radiation therapy
usually has a more delayed onset.
Patients with mucositis are at risk of infection
from spread of oral bacteria.
Narcotics are frequently required to achieve
adequate analgesia.
In its most severe form, pseudomembrane
formation, edema, and bleeding may cause
airway compromise or risk of aspiration.
Radiation to the head and neck can result
in permanent tissue fibrosis that may
limit mouth opening and neck and
tongue mobility.
Airway fibrosis and tracheal stenosis may
result in difficulty in ventilation and
intubation that is not recognized on
physical examination.
Preoperative evaluation of patients with
cancer includes consideration of the
pathophysiologic effects of the disease
and recognition of the potential adverse
effects of cancer treatments (Table 23-4).
In addition, the patient's underlying
medical comorbidities must not be
overlooked.
Correction of nutrient deficiencies,
electrolyte abnormalities, anemia, and
coagulopathies may be needed
preoperatively.
In most cases, laboratory evaluation should
include:
-complete blood count
-coagulation profile
- serum electrolyte concentrations
-transaminase levels.
Chest radiography, echocardiography,
pulmonary function evaluation, and other
specialized testing should be used if
clinical suspicion warrants.
chemotherapeutic drugs have the
potential to impair wound healing,
especially the growth factor and
angiogenesis inhibitors.
It has been suggested that surgery be
delayed for 4 to 8 weeks after treatment
with bevacizumab because of an
increased risk of bleeding and
postoperative wound complications.
Potential pulmonary or cardiac toxicity is a
consideration in patients being treated with
chemotherapeutic drugs known to be associated
with these complications.
The myocardialdepressant effects of anesthesia can
unmask cardiac dysfunction related to cardiotoxic
chemotherapeutic drugs such as doxorubicin.
Therefore, when major surgery is planned,
preoperative echocardiography may be indicated.
Since several chemotherapeutic agents can cause
electrocardiographic abnormalities such as QT
prolongation, a baseline electrocardiogram should
be reviewed.
A preoperative history of drug-induced
pulmonary fibrosis (dyspnea, nonproductive
cough) or congestive heart failure will
influence the subsequent management of
anesthesia.
In patients treated with bleomycin, it may
be helpful to perform arterial blood gas
monitoring in addition to oximetry and to
carefully titrate intravascular fluid
replacement, since these patients are at risk of
developing interstitial pulmonary edema,
presumably because of impaired lymphatic
drainage in the lung.
Bleomycin-associated pulmonary injury
may be exacerbated by high oxygen
concentrations; therefore, it is prudent to
adjust the delivered oxygen concentration
to the minimum that provides adequate
oxygen saturation.
Nitrous oxide may augment the toxicity of
methotrexate, so it is best avoided.
The presence of hepatic or renal dysfunction
should influence the choice and dose of
anesthetic drugs and muscle relaxants. the
possibility of a prolonged response to
succinylcholine is a consideration in patients
being treated with alkylating chemotherapeutic
drugs like cyclophosphamide.
The presence of paraneoplastic syndromes such
as myasthenia gravis and Eaton-Lambert
syndrome may also affect the patient's response
to muscle relaxants.
Attention to aseptic technique is important,
because immunosuppression occurs with most
chemotherapeutic agents and is exacerbated
by malnutrition. Immunosuppression
produced by:
1-anesthesia,
2 -surgical stress,
3- blood transfusion during the perioperative
period could have deleterious effects on the
patient's subsequent response to his or her
cancer.
Adrenal suppression may be present in
patients who are being treated with steroids.
Those who have been receiving more than
20 mg of prednisone (or its equivalent) per
day for longer than 3 weeks are considered
most at risk.
Recovery of the hypothalamic- pituitaryadrenal axis may take up to a year.
A typical steroid replacement regimen is
hydrocortisone 100 mg IV administered at
induction of anesthesia followed by 100 mg
IV every 8 hours for the first 24 hours after
surgery.
Intubation in the presence of oral
mucositis may cause bleeding.
Patients with cancers of the head, neck,
and anterior mediastinum may exhibit
airway compromise.
Patients with a history of radiation
exposure may have airway deformities
that are difficult to recognize on physical
examination.
Recent evidence suggests that anesthetics and
analgesics have immunomodulatory
properties.
Intravenous opioids tend to blunt natural killer
cell activity, producing an immunosuppressive
effect that supports the proliferation of tumor
cells.
The use of neuraxial anesthesia may preserve
the host's intrinsic anticancer defenses better
than general anesthesia. However,
coagulopathies may prevent the use of these
techniques in some cancer patients.
Peripheral nerve blocks may be utilized, but
baseline peripheral neuropathies related to
chemotherapeutic drugs such as vincristine
and cisplatin should be well documented.
Postoperative care must include adequate
attention to pain management.
Many cancer patients have been treated
for pain related to their underlying
diagnosis. Therefore, narcotic dosing
must be adjusted to account for possible
drug tolerance.
Prophylaxis against infection and
thromboembolism must also be
considered.
Have a nice day