PEDs Exam 2 Flashcards
what makes up hemoglobin A
two polypeptide alpha chains
two polypeptide beta chains
what makes up hemoglobin F
two alpha chains
two gamma chains
where is the binding site for 2,3-DPG
on the beta chain which is absent in fetal hemoglobin
what is the hgb of term neonate
17g/dL
HgbF replaced with Hgb A
8-12 weks
10g/dL
what ps P50 at term
19mmhg
what is P50 at 6 months
27mmhg
infants with RDS ____with adult blood transfusion
improve
hgb begins to increase at
around 4 months
neonate has physiological anemia due to what
decrease in erythropoietin
signs of anemia of prematurity
tachycardia
bradycardia
apnea
delayed growth
poor weight gain
prolonged anemia
where is ABO locus encoded
chromosome 9
what is the most important Rh antigen
D
individuals with Rh D antigen are considered
Rh positive
what happens when you give Rh- Rh+ blood
produce IgG antibodies against D antigen
hemolysis of transfused RBC
Rh is autosomal
dominant
when do Rh - mothers get the RhoGAM shot
26-28 weeks
also within 72 hrs after delivery
maternal IgG is present in infants less than
4 months
what type of blood do you transfused for all newborns
type O-
or
utilize ABO and RH D compatible blood
what should you test infant serum for
maternal anti A and Ant B alloantibodies
what clotting factors are in FFP
2
7
8
9
10
11
what clotting factors are in PCC
2 7 9 10 12
protein C
protein S
what factors are in cryo
fibrinogen
vWF
Whole blood is best, BUT:
Stored blood: Factors 5 and 8 depleted and PLT lose shape
Fresh whole blood is best
Use whole blood for exchange transfusion, after CPB, ECMO, massive transfusion
10 mL/kg of pRBCs in CPDA-1 increases the hemoglobin
by 3g/dl
PRBC characteristics
Stores with CPDA-1 or Adsol (AS)
250-300ml
60% Hct
Storage 35-42 days Days
10 mL/kg of pRBCs in CPDA-1 increases the hemoglobin by 3 g/dL
15 mL/kg is required to attain the same increment in hemoglobin when using pRBCs stored in AS
3 Accepted Indications for PRBC
To increase oxygen-carrying capacity
To avoid an impending inadequate oxygen-carrying state
Suppress the production or dilute the amount of endogenous hemoglobin in selected patients with thalassemia or sickle cell disease
guidelines for transfusion less than 4 months
when are transfusions rarely and almost always indicated
rarely hgb>10g/Dl
almost always Hgb <6
allowable blood loss calculation
Hi = Pt’s Initial Hematocrit
Hp = Minimal accepted Hct (depends on condition) Average ~ 24%
Hav = Average of Hi & Hp
Allowable blood loss = EBV × (Hi – Hp)/Hav
estimated blood volume for premature infants
90-100 ml/kg
estimated blood volume for term newborns
80-90 ml/kg
estimated blood volume for infants <1 year old
75-80 ml/kg
estimated blood volume for older children
70-75ml/kg
whats the equation for volume of PRBC to administer
what are characteristics of cyanotic congenital heart disease
Require a higher oxygen-carrying capacity
Polycythemia develops
Historically – maintain Hgb of 13 to 18 g/dL
list transfusion complications
viral infections (HIV HCV, fatal hemolysis)
bacterial infections
hyperkalemia
TRALI
what decreases risk of TRALI
male only FFP donors
S/S of TRALI
ARDS – dyspnea, hypoxia, pulmonary edema, onset 4-6 hours after transfusion
what is treatment for TRALI
supportive care
what qualifies as a massive transfusion
more than one blood volume in a 24 hr period
50% blood volume in 3 hrs
10% of blood volume every 10 min
massive transfusion complication chart
what are some techniques to reduce blood transfusions
Autologous blood transfusion
Acute Normovolemic Hemodilution
Deliberate Hypotension
TXA
which hemostatic factors are decreased in neonates
2,7,9,10,11,12,
plasminogen,
TFPI
AT
PC
PS
which hemostatic factors are increased in neonates
increased vWF, 8 alpha2m,
what does vWF do
platelet adhesion to injured blood vessels by bridging exposed collagen to activated platelets
Aids platelet aggregation in conjunction with fibrinogen through interactions with platelet GPIIb/IIIa surface receptor
Carrier protein for Factor 8 (protects it from activated protein C)
what are S/S of Von Willebrand disease
easy bruising
petechia
nose bleeds
low factor 8
type 1 Von Willebrand disease
mild-mod Quantitative decrease
TX: DDAVP – stimulates release of vWF from storage sites
Repeated use tachyphylaxis, hyponatremia, volume overload
type 2 von willebrand disease
qualitative abnormal vWF (20% of cases)
type 3 von willebrand disease
severe Quantitative decrease
TX: increase levels of vWF & factor 8
Virally inactivated plasma-derived vWF concentrates (with or without FVIII) or recombinant vWF may be required.
what do labs look like for hemophilia
Isolated prolongation of the aPTT,
normal PT, thrombin time, platelet count, and bleeding time
treatment for hemophilia
raise F8 or F9 with concentrated factors
DDAVP for F8 short term
what is the most common reason for thrombocytopenia in childhood
idiopathic thrombocytopenia purpura (ITP)
lifespan of ITP platelets
few hrs
how do you treat ITP
observation alone in children presenting with no bleeding or mild bleeding w/ vigilance
for severe bleeding
Severe bleeding: emergent transfusion, possible splenectomy
diagnosis of ITP
platelet count of less than 100 × 109/L without concurrent leukopenia or anemia.
what is Glucose-6-Phosphate Dehydrogenase Deficiency
Most common human enzyme deficiency
Causes acute hemolysis in the presence of various oxidative stressors
Fava beans, methylene blue, nitrofurantoin
Forms Heinz bodies -> lysis of RBC -> jaundice and anemia
what is the gold standard test for Glucose-6-Phosphate Dehydrogenase Deficiency
quantitative spectrophotometric assay of G6PD activity
Don’t test during acute hemolysis episode – test 2 months later
how do you treat patients with G6PD
Avoidance of the agents known to trigger hemolysis is of paramount importance like:
Hydralazine, Procainamide, Methylene blue, ASA, Sulfa drugs
Fortunately, narcotics, benzodiazepines, propofol, and ketamine are safe to use in these patients
s/s of G6PD
neonatal jaundice,
acute hemolytic anemia,
chronic nonspherocytic
hemolytic anemia
alpha thalassemia
Alpha-trait (2 genes) – asymptomatic with mild microcytic, hypochromic anemia
alpha thalassemia intermedia ( 3 genes affected) & Major (4 genes)
Bart’s hemoglobin – 4 gamma chains (high affinity for O2)
->hydrops fetalis and intrauterine death
beta thalassemia
One Gene = silent carrier
beta thalassemia intermedia = mild to moderate reduction in beta globin chain
beta thalassemia major, or “Cooley’s anemia” – SEVERE reduction beta globin chain
Presents between 6 and 24 months of life with pallor, jaundice, growth retardation, and hepatosplenomegaly and can be fatal if untreated
Bony deformities in the face 2/2 ineffective erythropoiesis
what is the anesthesia management for thalassemia
Consider face deformities
Osteoporosis
Hyperdynamic circulation
Cardiac dysfunction
Hepatic disease
Pulmonary hypertension
Thrombosis risk (anticoagulants precribed?)
what is the most coomon inherited RBC disorder
sickle cell anemia
sickle cell anemia traits
HbS results from substitution of valine for glutamic acid at the 6th position
Sickle Cell Anemia = Homozygous = produce only HbS
s/s of sickle cell anemia
Hemolysis and recurrent vasoocclusive episodes that cause severe pain (“crises”) and lead to progressive organ dysfunction
Emotional stress, pain, infection, surgical stress ->increased vasocclusive disease, constriction, RBC trapping -> Ischemia/Infection
lifespan of Sickle cell anemia RBC
10-12 days which results in anemia
what procedure does sickle cell patients often need
lap chole
sickle cell acute splenic sequestration
Age 1 – 4
Traps RBC in splenic sinusoids ->severe anemia, hypovolemia, shock
Tx: aggressive fluids, RBC, splenectomy
Splenic involution is complete by 5 years of age
what is the leading complications in SCD
Pulmonary and neurologic complications are the leading causes of morbidity and mortality in individuals with SCD
acute chest syndrome
New pulmonary infiltrate involving at least one complete lung segment on chest x-ray and is the leading cause of death in patients with SCD
acute chest syndrome triggers
infection, fat embolism from bone marrow infarction, pulmonary infarction, and surgery-induced stress
s/s of acute chest syndrome
Chest pain, fever, tachypnea, wheezing, coughing, and hypoxemia
Tx: broad-spectrum antibiotics, supplemental oxygen, adequate analgesia, bronchodilators, and incentive spirometry
treatment for acute chest syndrome
APAP
NSAIDS
steroids
opioids
psychotropics
regional anesthesia
indications for SCD transfusion
correction of a preexisting anemia
dilution of hemoglobin S concentration (to less than 30%)
Intraoperative Management of Coagulopathies
Whole blood
PRBC
FFP
Cryoprecipitate
Concentrated factors
Others: TXA
FFP facts
Must be frozen within 8 hours of collection to preserve labile coagulation factors V and VIII
Must be transfused within 24 hours after thawing
20 mL/kg of FFP will replace approximately 50% of most coagulation factors
what is in FFP
Contain all of the clotting factors, fibrinogen (400 to 900 mg/unit), plasma proteins (particularly albumin), electrolytes, physiological anticoagulants (protein C, protein S, antithrombin, tissue factor pathway inhibitor) and added anticoagulants
cryo facts
controlled thawing of FFP to 1° to 6° C to precipitate and extract the high molecular weight proteins
Each unit of cryoprecipitate has a minimum of 80 IU of FVIII activity and 15 g/L of fibrinogen
One unit of cryoprecipitate is transfused per 5 kilograms of weight and should increase a child’s fibrinogen by approximately 100 mg/dL
One platelet concentrate per 10 kg of body weight will increase the platelet count by
approximately 50 × 109/L.
random donor platelet replacement for neonates
5-10 ml/kg
random donor platelet replacement for older infants
0.1-0.2 units/kg
single donor platelet replacement for neonates
10ml/kg
single donor platelet replacement for children
less than 15kg= 1/4 unit
15-30kg =1/2 unit
over 30kg = whole unit
DDAVP facts
Synthetic analogue of the posterior pituitary hormone – AVP
Little effect on blood pressure (unlike vasopressin)
Does NOT stimulate ACTH release like AVP
Acts primarily at the renal collecting duct to limit the amount of water eliminated in the urine
Preferred treatment for patients with type 1 von Willebrand disease.
Increases circulating levels of procoagulant factor VIII : C and vWF
