Oncological emergencies
Introduction:
Oncological emergencies are life-threatening emergencies that can occur as
result of cancer or cancer treatment. These emergencies can be obstructive, metabolic, or infiltrative.
1. Obstructive emergencies
:
·
Caused by tumour obstruction of an organ
or blood vessel.
·
Include superior vena cava syndrome, spinal cord compression syndrome, third
space syndrome and intestinal obstruction.
A.
Superior
vena cava syndrome
·
Considered a serious medical problem
·
Results from obstruction of the superior
vena cava by a tumour or thrombosis.
·
The clinical manifestations include facial
oedema, periorbital oedema, and distention of veins of the head, neck, and
chest, headache, and seizures.
·
A mediastinal mass is often visible on
chest x-ray
·
The most common causes are lung cancer,
non-Hodgkin's lymphoma, and metastatic breast cancer.
·
Management involves radiation therapy to
the site of obstruction.
·
Chemotherapy may be administered for
tumours more sensitive to this form of therapy.
B. Spinal cord compression
: A neurologic emergency caused by the presence of a malignant tumour in the
epidural space of the spinal cord
Tumours
causing spinal cord compression
·
Breast Cancer
·
Prostate cancer
·
Renal tumours
·
lung cancer
·
GI cancer
·
Melanoma
Clinical
Manifestations
·
Localized, persistent and Intense back
pain
·
vertebral tenderness and aggravated by the
Valsalva maneuver
·
motor weakness and dysfunction
·
Sensory paraesthesia
·
Autonomic dysfunction.
Management
·
Radiation therapy in conjunction with prompt
initiation of corticosteroids
·
Activity limitations
·
Pain management
·
Surgical decompressive laminectomy
C.
Third
Space Syndrome
Involves a shifting of
fluid from the vascular space to the interstitial space.
Occurs secondary to
extensive surgical procedures, biologic therapy, or septic shock.
Signs
and symptoms
·
Hypovolemia
·
low central venous pressure
·
Decreased urine output
·
Hypotension .
·
Tachycardia
Treatment:
Fluid, electrolyte, and plasma protein replacement and Fluid balance monitoring
D.
Intestinal
Obstruction
Mechanical obstruction
due to tumours in the bowel.
Symptoms include: nausea,
vomiting, abdominal pain, distension, inability to pass flatus.
Management:
Emergency surgery for strangulated bowel, NPO, Insertion of Ryle’s tube and
abdominal decompression, IV fluid resuscitation.
2.
Metabolic
Emergencies
Caused by the production
of ectopic hormones directly from the tumour or are secondary to metabolic
alterations caused by the presence of the tumour or cancer treatment.
Metabolic
Emergencies
Syndrome of inappropriate
antidiuretic hormone secretion (SIADH)
Hypercalcemia
Tumour lysis syndrome
(TLS)
Septic shock
disseminated
intravascular coagulation (DIC)
A.
Syndrome
of Inappropriate Antidiuretic Hormone Secretion (SIADH)
Results from abnormal or sustained production
of antidiuretic hormone (ADH)
Results in water retention and hyponatremia
Most frequently in
carcinoma of the lung but can also occur
in cancer of the pancreas, duodenum, brain, oesophagus, colon, ovary, prostate,
bronchus, and nasopharynx; leukaemia, mesothelioma,reticulum cell sarcoma,
Hodgkin's lymphoma and thymoma( a tumour originating from the epithelial cells of the thymus).
Signs
and symptoms: Weight gain, weakness, anorexia, nausea,
vomiting, personality changes,seizures, and coma
Treatment: treating the
underlying malignancy and measures to correct the sodium-water balance, fluid
restriction and in severe cases, IV administration of 3% sodium chloride
solution.
B. Hypercalcemia: Occur
in the presence of cancer that involves metastatic disease of the bone or multiple
myeloma, or when a parathyroid hormone-like substance is secreted by cancer
cells. Occurs in patients with lung, breast, kidney, colon, ovarian, or thyroid
cancer, squamous cell carcinoma of the lung; head and neck, cervical, and oesophageal
cancer; lymphomas; and leukaemia.
Signs
and symptoms
Apathy, depression,
fatigue, muscle weakness, ECG changes, polyuria and nocturia, anorexia, nausea
and vomiting.
Treatment:
·
Treat the primary disease
·
hydration & bisphosphonates
·
bisphosphonates, (inhibits the action of
osteoclasts)
C.
Tumour
Lysis Syndrome (TLS)
·
A metabolic complication characterized by
rapid release of intracellular
components in response to chemotherapy.
·
Associated with tumours that have high
growth rate
·
Releases a host of intracellular
components into the bloodstream including potassium, phosphate, and DNA and RNA
components
Sign and
symptoms
·
The four hallmark signs are hyperuricemia,
hyperphosphatemia, hyperkalemia, and hypocalcaemia
·
Usually occurs within the first 24 to 48
hours after the initiation of chemotherapy and may persist for approximately 5
to 7 days
Treatment
·
Goal is to prevent renal failure and
severe electrolyte imbalances.
·
Hydration therapy
·
Decreasing uric acid concentrations using
allopurinol.
D.
Septic
shock and disseminated intravascular coagulation (DIC)
·
Septic shock is a systemic disease
associated with the presence and persistence of pathogenic microorganisms or
their toxins in the blood.
·
It is characterized by hemodynamic
instability, abnormal coagulation, and altered metabolism
Management
·
Antibiotics are started immediately;
broad-spectrum antibiotics are given until organism is identified.
·
I.V. fluids and plasma expanders are used
to restore circulating volume.
·
Colony-stimulating factors are
administered to increase neutrophil count.
·
Vasopressors are administered to support
blood pressure.
·
Oxygen is administered as needed to
prevent tissue hypoxia.
3.
Infiltrative
Emergencies
·
occur when malignant tumours infiltrate
major organs or secondary to cancer therapy.
·
The most common infiltrative emergencies
are cardiac tamponade and carotid artery rupture.
A. Crdiac Tamponade : Results
from fluid accumulation in the pericardial sac, constriction of the pericardium
by tumour, or pericarditis secondary to radiation therapy to the chest
Signs
and symptoms : Heavy feeling over the chest, shortness
of breath, tachycardia, cough, dysphagia, hoarseness, nausea,vomiting,decreased
level of consciousness, excessive perspiration, pulsus paradoxus, distant or
muted heart sounds, and extreme anxiety.
Management
Emergency management is
aimed at reduction of fluid around the heart
Surgical establishment of
a pericardial window or an indwelling pericardial catheter,
Administration of oxygen
therapy, intravenous hydration and vasopressor therapy
B. Carotid Artery Rupture :
Occurs most frequently in patients with cancer of the head and neck secondary
to invasion of the arterial wall by tumour or to erosion therapy
Signs
and symptoms: Bleeding can manifest as minor oozing or
spurting of blood in the case of a "blowout" of thc artery.
Management:
In the presence of a
blowout, pressure should be applied to the site with a finger.
Intravenous fluid and
blood products
Stabilize the patient for
surgery.
Surgical management
involves ligation of the carotid artery above and below the rupture site and
reduction of local tumour.
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