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Approach to Coagulopathic Patients
1:50 p.m. Approach to Coagulopathic Patients john R. Haaga, MD University Hospitals of Cleveland Cleveland, OH 2:10 p.m. Complications of Biopsy/Drainage jeet Sandhu, MD Danbury Hospital Danbury Radiologic Associates Danbury, CT 2:30 p.m. Methods of Biopsy/Drainage in Poorly Accessible Lesions Ronald S. Arellano, MD Boston, MA 2:50 p.m. PANEL DISCUSSION
, Pediatric IR for the Non-Pediatric IR (CC) Coordinator / Moderator: Patricia E. Burrows, MD 1:30 p.m. General Principles: Patient Care and Arterial Access Patricia E. Burrows, MD Children's Hosp~tal Boston, MA Indications Children, especially infants, are more vulnerable to certain complications of vascular interventions than are adults Therefore, procedures requiring arterial cannulation are generally pelformed in children only when absolutely necessary, after noninvasive imaging has been exhausted. MR angiography and diagnostic ultrasound can resolve most issues regarding vascular anatomy and pathology. Exceptions include acute or chronic hemorrhage, CNS hemorrhage, explained CNS ischemia and severe hypertension, which should be evaluated by diagnostiC arteriography early in order to institute appropriate treatment. Vascular malformations rarely require diagnostic arteriography for diagnosis: generally, angiography is carried out at the time of endovascular treatment. Risks Arterial injUry, hypothermia and over-administration of contrast medium and flUids are the most common complications of angiography in young children. Femoral Artery Catheterization It has been estimated that femoral artelY thrombosis occurs in as many as 100/0 of children undergoing angiography under one year of age. The incidence is lower
in the hands of experienced pediatric interventionalists. Much of the research into the etiology and prevention of this complication was done by pediatric cardiologistS. The pathogenesis is believed to be thrombus formation at the site of intimal injury, aggravated by arterial spasm and decreased flow through the arteriotomy site. Infants and children have reactive arterial smooth muscle and typically develop catheter-induced arterial spasm. The artery is further traumatized by prolonged catheter manipulation (in the absence of an introducer sheath), catheter exchanges, and excessive pressure on the arteriotomy site during and after catheter removal. Diminished flow through the catheterized extremity is aggravated by decreased temperature of the catheterized limb, excessive flexing of the hip post catheter removal, groin hematoma and tight pressure dressings. Prevention of femoral altery thrombosis is preferable to treatment. Conditions for femoral artery cannulation should be optimized by the use of sedation or general anesthesia, hip elevation, small needle and catheter systems (e.g. 4F micropuncture set), 4F arterial sheath and administration of a bolus of heparin (50 to 100 units per kg for infants 15 kg and smaller) after arterial cannulation. Heparin boluses can be repeated after one to two hours. Pedal pulses should be checked prior to removing the sheath. If they are absent, contrast injection should be made through the sheath, and if the artery is occluded, a small amount of nitroglycerine 0.5 micrograms per kilogram) can be infused through the sheath as it is being withdrawn. Pressure on the groin should be minimal, only enough to prevent bleeding. Lower extremities should be kept warm during and after angiography and the patient should be kept well hydrated. For patients who exhibit excessive movement following the procedure, sedation may be necessary. Pressure dressings can be applied as a last resort, but must be adjusted so that the pedal pulses are still palpable after application. Treatment of Femoral Artery Thrombosis The diagnosis of femoral altery thrombosis is often delayed unnecessarily. Any infant or child with absent pedal pulses (by palpation) post arteriotomy has femoral artery thrombosis until proven otherwise. Pallor, reduced temperature of the affected limb and slowed capillary refill are additional signs of limb ischemia. The ability to detect pedal pulses by Doppler should not be reassuring. Extensive arterial collaterals between the femoral arteries distal to the puncture site and the internal iliac artery can result in sufficient flow to permit detection of pedal pulses by Doppler, or even faintly by palpation. In the presence of reduced distal perfusion, the patient should be heparinized and an ultrasound examination of the iliofemoral vessels carried out. If this shows patency of the iliofemoral system, further heparinization is probably not necessary, as long as the patient is closely monitored. If the femoral artery is occluded, the patient should be kept therapeutically
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, Pediatric IR for the Non-Pediatric IR (CC) Coordinator / Moderator: Patricia E. Burrows, MD 1:30 p.m. General Principles: Patient Care and Arterial Access Patricia E. Burrows, MD Children's Hosp~tal Boston, MA Indications Children, especially infants, are more vulnerable to certain complications of vascular interventions than are adults Therefore, procedures requiring arterial cannulation are generally pelformed in children only when absolutely necessary, after noninvasive imaging has been exhausted. MR angiography and diagnostic ultrasound can resolve most issues regarding vascular anatomy and pathology. Exceptions include acute or chronic hemorrhage, CNS hemorrhage, explained CNS ischemia and severe hypertension, which should be evaluated by diagnostiC arteriography early in order to institute appropriate treatment. Vascular malformations rarely require diagnostic arteriography for diagnosis: generally, angiography is carried out at the time of endovascular treatment. Risks Arterial injUry, hypothermia and over-administration of contrast medium and flUids are the most common complications of angiography in young children. Femoral Artery Catheterization It has been estimated that femoral artelY thrombosis occurs in as many as 100/0 of children undergoing angiography under one year of age. The incidence is lower
in the hands of experienced pediatric interventionalists. Much of the research into the etiology and prevention of this complication was done by pediatric cardiologistS. The pathogenesis is believed to be thrombus formation at the site of intimal injury, aggravated by arterial spasm and decreased flow through the arteriotomy site. Infants and children have reactive arterial smooth muscle and typically develop catheter-induced arterial spasm. The artery is further traumatized by prolonged catheter manipulation (in the absence of an introducer sheath), catheter exchanges, and excessive pressure on the arteriotomy site during and after catheter removal. Diminished flow through the catheterized extremity is aggravated by decreased temperature of the catheterized limb, excessive flexing of the hip post catheter removal, groin hematoma and tight pressure dressings. Prevention of femoral altery thrombosis is preferable to treatment. Conditions for femoral artery cannulation should be optimized by the use of sedation or general anesthesia, hip elevation, small needle and catheter systems (e.g. 4F micropuncture set), 4F arterial sheath and administration of a bolus of heparin (50 to 100 units per kg for infants 15 kg and smaller) after arterial cannulation. Heparin boluses can be repeated after one to two hours. Pedal pulses should be checked prior to removing the sheath. If they are absent, contrast injection should be made through the sheath, and if the artery is occluded, a small amount of nitroglycerine 0.5 micrograms per kilogram) can be infused through the sheath as it is being withdrawn. Pressure on the groin should be minimal, only enough to prevent bleeding. Lower extremities should be kept warm during and after angiography and the patient should be kept well hydrated. For patients who exhibit excessive movement following the procedure, sedation may be necessary. Pressure dressings can be applied as a last resort, but must be adjusted so that the pedal pulses are still palpable after application. Treatment of Femoral Artery Thrombosis The diagnosis of femoral altery thrombosis is often delayed unnecessarily. Any infant or child with absent pedal pulses (by palpation) post arteriotomy has femoral artery thrombosis until proven otherwise. Pallor, reduced temperature of the affected limb and slowed capillary refill are additional signs of limb ischemia. The ability to detect pedal pulses by Doppler should not be reassuring. Extensive arterial collaterals between the femoral arteries distal to the puncture site and the internal iliac artery can result in sufficient flow to permit detection of pedal pulses by Doppler, or even faintly by palpation. In the presence of reduced distal perfusion, the patient should be heparinized and an ultrasound examination of the iliofemoral vessels carried out. If this shows patency of the iliofemoral system, further heparinization is probably not necessary, as long as the patient is closely monitored. If the femoral artery is occluded, the patient should be kept therapeutically
P251