In the name of God Dr. M.Habibi Neonatologist Assistant professor of pediatrics

Vasospasms and thromboembolism in neonate: *Cause : usually occur with indwelling arterial or sometime venous catheters. More commonly umbilical & less common with peripheral line. Neonates are at a high risk because of their : A: immature hemostatic system B: smaller vessel size Vasospasm commonly occur in arterial catheterization but thromboembolism common with venous catheterization. * most medications if given too rapidly can cause vasospasms

*risk factors : A) Maternal: 1) Autoimmune disorder 2) PROM 3) Diabetes 4) Preeclampsia 5) Oligohydramnios 6) Prothrombotic disorder 7) Chorioamnionitis 8) familial history of thrombosis 9) anti-phospholipid or anti-cardiolipin Ab

B)Delivery : 1) Instrumentation 2) Fetal heart rate abnormality 3) C/S Emergency 4) Traumatic delivery

C) Neonate : 1) C.A.C (central arterial catheter)is the most common risk factor 2) Central venous catheters 3) Congenital heart disease 4) Asphyxia 5) Sepsis 6) SGA & IUGR 7) RDS 8) NEC

9) Polycytemia 10) PPHN 11) Dehydration 12) Congenital Nephrotic syndrome 13)DIC 14) Impaired liver function 15) low cardiac output & hypotention 16) Prothrombotic disorder ( protein C & S deficiency, factor V leiden mutation, anti-thrombin deficiency , elevation of lipoprotein A level & other things like impaired liver function.)

ɪ) Vasospasm: a. Less severe vasospasm: Due to muscular contraction it is commonly arterial 1. catheter 2. injection of medication 3. Sampling a. Less severe vasospasm: Involves a small area of one or both legs (usually some of the toes and parts of the foot or hand) * in this type : skin has a mottled appearance & pulses are present but diminished.

b. severe vasospasm: Involves large area of one or both extremity and sometime progresses to buttocks and abdomen. * in this type: skin maybe completely white -Perfusion decreased -Pulses of affected extremity are week but detectable

Arterial thrombosis: Venous thrombosis : Is a medical emergency in which pulse usually are completely absent & persistent bacteremia & thrombocytopenia may be associated with thrombosis Venous thrombosis : More common and it’s first sign is catheter dysfunction Extremities are swollen – cyanotic –hyperemic and discolored with distended superficial veins but renal vein thrombosis is most common type of spontaneous venous thrombosis

Laboratory studies: Not usually needed for vasospasm but in suspected thromboembolism following studies should be done: 1.Coagulation profile : PT, PTT , TT ,Plasma fibrinogen concentration. 2.Hb & HCT 3.Platelate count & function (BT) 4.CMV workup 5.workup for thrombotic disorder (Protein C & S & anti-thrombin ɪɪɪ - factor V leiden & antiphospholipid & cardiolipin Ab

Imaging: 1. Plain radiograph of the abdomen (for catheter placement) 2.ultrasound (Doppler flow) for thrombosis(also evaluate Brain & kidney sonography) arterial 3.Contrast angiography ( gold standard) Venous 4.magnetic resonance (MR)angiograph Is done in some centers especially for suspected stroke.

Some general recommendations for Prophylaxy: 1. Small catheters should be used 2. heparin is used for patency of peripheral and central Arterial catheter 25-200 u/kg/d(0.5unit/ml)concentration 3.heparin is not used in peripheral venous line 4.in central venous and PICC sometimes Heparin is recommended 5.Umblical line Should be removed as soon as possible ; arterial line should not be in place longer than 5 days and venous line not longer than 14 days. 6.PICC line has lower incidence of thrombosis. 7.Use peripheral line over umblical line.

Management: A)Vasospasm: Guide lines vary extensively 1. If possible remove the catheter 2.Warming the contra lateral extremity wrapping of unaffected extremity should cause reflex vasodilation of the affected vessels . continue it for 15-30 min. 3.Gentle massage at the Site of occlusion) 4.Topical nitroglycerin therapy (2%ointment)4 mm/kg every 8 hours for (2-27day) improvement usually seen within 15-45 min.

5. If it is not possible to remove the catheter (it is the only line) consider papaverin 60 mg/500cc/N/s with 0/1unit/ml heparin continuous for 48 hr if vasospasm persist removed catheter. 6.lidocaine(controversial) 2mg/kg/hr 7.Morphine 8.surgery (sympathectomy)

B) Thromboemboli : ** Supportive care ** 1.prompt removal of the catheter 2.treatment of volume depletion- Electrolyte abnormality – Sepsis – Thrombocytopenia – anemia 3.Emergency consultant with surgeon & hematologist 4.Evaluate for IVH 5.Rule out contraindication of anticoagulant & thrombolytic therapy (surgery & asphyxia in the last 10 days) – severe coagulation deficiency – platelate under 50000 – fibrinogen under 100 mg/dl – INR>2