CR - Hematologic / Oncologic Disorders Flashcards
In which area of the body is central cyanosis likely to be detected?
The lips/tongue, oral membranes (especially buccal mucosa) or conjunctivae, hands/feet
In which clinical entity is there severe tissue hypoxia but NO peripheral cyanosis?
Carbon monoxide poisoning
What are the causes of central cyanosis?
Hemoglobinopathies / polycythemia (ie. methemoglobinemia, COHb, SulfaHb)
V/Q mismatches (bronchospasm, PE, pneumonia, bronchiolitis, pulm HTN, COPD, hypoventilation)
Cardiovascular causes (HF, congenital heart disease, valvular heart disease)
High altitude
Decreased arterial oxygen saturation
Anatomic shunts
Abnormal skin pigmentation from heavy metal poisoning or medications can mimic cyanosis
Obstructive sleep apnea
Hypothermia
Note - cold exposure causes peripheral cyanosis
Aseptic necrosis of the femoral head is associated with which blood disorder?
Sickle cell disease
Why are o-negative packed cells preferable to o-negative whole blood prior to cross-match
O-negative packed cells are less concentrated with anti-A and anti-B antibodies
(reminder - o-positive blood can be used in men and postmenopausal women)
What is the most common congenital bleeding disorder?
Von Willebrand’s Disease
What are the potential complications of auto-transufion?
Air embolus
Citrate toxicity
Dilutional coagulopathy, if volume is >3500 ml
Sepsis if contaminated blood is infused
Hemolysis, if the blood has pooled within the pleural cavity for more than 6 hours
Microemboli and acute kidney injury
Clinical presentation: a patient is seen with shortness of breath, swelling and plethora of the face and upper extremities, and headache.
What is the diagnosis?
Superior vena cava syndrome
Common complaints are HA, dizziness, change in vision, dyspnea, orthopnea, cough and skin with violet hue
Rare but serious clinical consequences: cerebral edema, upper respiratory compromise due to larynx and pharynx edema
Which drugs should you avoid in patients with glucose 6-phosphate dehydrogenase (G6PD) deficiency?
Quinolones/fluoroquinolones, sulfa (furosemide, dapsone, etc), glyburide, probenecid, penicillamine
Sulfa
Rasburicase
Pyridium
Nitrofurantoin
Anitmalarials
Dapsone
Methylene Blue
Aspirin
NSAIDs
Can thrombocytopenia result from an exchange transfusion?
Yes, a dilutional thrombocytopenia can occur with exchange transfusion.
Dilutional thrombocytopenia occurs in cases of massive transfusion, exchange transfusion or extracorporeal circulation
You are seeing a child who took some of Grandpa’s warfarin. There is no evidence of bleeding and the PT is normal. Do you administer vitamin K or just observe him?
Observe.
Vitamin K is indicated for serious bleeding since the result of overdose is a functional deficiency of vitamin K
What is the most severe form of congenital anemia?
(clinical features include bronze skin discoloration and patients are transufions-dependent)
Beta-thalassemia
(thalassemia major, cooley’s anemia)
This is often misdiagnosed as iron deficiency anemia on blood smear (hypochromic, microcytic red cells). Bronze skin is from multiple transfusions
Clinical presentation: a neutropenic patient develops sepsis associated with non-productive cough and fever with rales at both bases. He also has an infected sacral decubitus ulcer.
What is the likely offending organism?
E. coli
Most common causative organisms isolated in patients with neutropenic septic shock: gram negative bacteria, particularly E. coli (77.1%). Pseudomonas should be covered, because it is commonly isolated in blood with respiratory tract infections, but by and large it’s E. coli
What is the most common virus causing life-threatening infection in patients undergoing bone marrow or solid organ transplants?
Cytomegalovirus
Bacterial pneumonia is now the most fatal infection post transplant
