Peds summary part 2 Flashcards
____ can be used to try and close a PDA
Indomethacin (an anti-prostaglandin)
The ductus arteriosus remains patient in utero due to
hypoxia, mild acidosis, & placental prostaglandins**
Left to right shunts
connects arterial and venous circulation resulting in increased pulmonary blood flow “pink lesions”***
ex. PDA, ASD, VSD
Right to left shunts
venous blood is ejected systemically; there is decreased pulmonary blood flow & patients are cyanotic “blue lesions”
- ex. ASD or VSD with pulmonary HTN, TOF during Tet spell
Eisenemenger’s syndrome:
when large VSDs are uncorrected the resulting pHTN can reverse the shunting of blood across the defect
the previous left to right shunt becomes right to left
- the shunt reverses direction when the PVR is high enough
The Qp/Qs is the
ratio of pulmonary to systemic blood flow
we use it to determine over circulation to the pulmonary system or LV workload
normal is equal to 1:1
tells us the degree of shunting
Coarctation
a narrowing in the aorta commonly occurring immediately distal to the origin of the left subclavian artery
critical coarctations will present with circulatory collapse, shock, & acidosis due to poor distal perfusion
- prostaglandin is started to reopen the ductus & distal perfusion remains ductal dependent until surgery
-presents with upper extremity hypertension, decreased lower extremity pulses & LVH
-surgical approach is left thoracotomy and subclavian flap angioplasty sacrifices the left subclavian artery & the left arm will then need to be perfused by collateralization
-blood pressure must be measured in the right arm
The Ross procedure
- performed on patients diagnosed with aortic stenosis & is an alternative to prosthetic valve replacement
- diseased aortic root is resected the patient’s own pulmonary valve root is excised & implanted into the aortic position
- coronary arteries are then re-implanted into the “neo-aortic” root
- An RV to PA connection and valve is made with cadaveric tissue or a conduit
- advantages: freedom from long-term anticoagulation, the valve grows as the patient grows
- disadvantages- single valve disease (aortic) is treated with 2 valve procedure
Blalock-Taussing-Thomas shunt
-operation to create a type of systemic to pulmonary shunt
Classic BTS- subclavian artery is divided and directly anastomosed to the ipsilateral pulmonary artery
- cannot take BP in left arm/ pulseless or weak pulse; grows with the individual
Modified BTS- synthetic shunt between the subclavian artery & PA
- ipsilateral arm reflects true pressures & available for a-line placement
-artificial material will not grow with the patient
-hypotension leads to sluggish flow & possibly thrombosis which can be critical**
Tetralogy of fallot
four key features: VSD, Right ventricular outflow obstruction, overriding aorta, right ventricular hypertrophy
limitation of pulmonary blood flow & the magnitude of ventricular level right to left shunting account for the degree of cyanosis
-TET spells are acute dynamic increases in the pulmonary outflow tract obstruction may result in an intensely cyanotic epidosde due to right to left shunting
Anesthetic treatment: 100% fiO2, sedation, fluid, beta blocker, alpha agonist to increase afterload & slow down the heart rate
Anesthesia for TOF reapir:
avoid “tet spell”
generous premedication
sufficient anesthesia & analgesia
avoid reductions in SVR
RV output is the limiting factor on overall CO
treat a tet spell quickly with phenylephrine
Treating a “Tet spell” intraoperatively includes:
exacerbated right to left shunting (cyanosis) 100% oxygen knees to chest fluid bolus hyperventilation sedation esmolol phenylephrine 1-10 mcg/kg IV
Postconceptual age=
gestational age + postnatal age
Marfan syndrome:
multisystem disorder resulting from a mutation in connective tissue protein
aortic or pulmonary artery dilation, mitral valve prolapse**
Anesthetic considerations: avoid hypertension b/c of risk for aortic dissection, increased risk for pneumothorax use careful PPV, careful positioning due to joint laxity, may require larger than normal doses of spinal or epidural medications due to increased length and increased CSF
Noonan syndrome:
autosomal dominant
anesthetic considerations: possible difficult intubation, difficult PIV placement with edema, chest deformities may lead to decreased lung function, bleeding diathesis may increase the amount of periop bleeding, renal impairment may affect metabolism of renally excreted drugs
spinal abnormalities may make epidural catheter placement diffuclt
SBE prophylaxis, & HOCM considerations
