Randomized study assessing the accuracy of cervical facet joint nerve (medial branch) blocks using different injectate volumes.

BACKGROUND: Neck pain is a frequent cause of disability, with facet joint arthropathy accounting for a large percentage of cases. The diagnosis of cervical facet joint pain is usually made with diagnostic blocks of the nerves that innervate them. Yet, medial branch blocks are associated with a high false-positive rate. One hypothesized cause of inaccurate diagnostic blocks is inadvertent extravasation of injectate into adjacent pain-generating structures. The objective of this study was to evaluate the accuracy of medial branch blocks by using different injectate volumes. METHODS: Twenty-four patients received cervical medial branch blocks, using either 0.5 or 0.25 ml of bupivacaine mixed with contrast. One half of the patients in each group were suballocated to receive the blocks in the prone position and the other half through a lateral approach. Participants then underwent computed tomography of the cervical spine to evaluate accuracy and patterns of aberrant contrast spread. RESULTS: Sixteen instances of aberrant spread were observed in nine patients receiving blocks using 0.5 ml versus seven occurrences in six patients in the 0.25 ml group (P = 0.07). Aberrant spread was most commonly observed (57%) when an injection at C3 engulfed the third occipital nerve. Among the 86 nerve blocks, foraminal spread occurred in five instances using 0.5 ml and in two cases with 0.25 ml. The six "missed" nerves were equally divided between treatment groups. No significant difference in any outcome measure was observed between the prone and lateral positions. CONCLUSIONS: Reducing the volume during cervical medial branch blocks may improve precision and accuracy.

Use of interlock fibered detachable coils for occlusion of collaterals, coronary artery fistulae, and patent ductus arteriosus.

OBJECTIVE: To investigate the utility of interlocking detachable coils (IDC) for transcatheter occlusion of vascular communications in congenital heart disease. BACKGROUND: The IDC can be delivered in a retractable fashion through hydrophilic Renegade microcatheters. They incorporate thrombogenic synthetic fibers and cost less than comparable neurovascular coils. They are ideally suited for use in many forms of congenital heart disease. METHODS: A retrospective review of all patients catheterized during the initial 18-month period of IDC availability at our institution was performed. Interlock coils were only used if traditional methods could not be used easily and safely. All congenital patients in whom IDC were used are described. RESULTS: A total of 61 coils were deployed in 17 patients with various vessels not amenable to treatment with conventional coils. Coils were used in aortopulmonary collaterals (n = 7), veno-venous collaterals (n = 9), patent ductus arteriosus (n = 3), and coronary artery fistulae (CAF) (n = 2). Operators were able to control coils and withdraw into the catheter for repositioning without difficulty. Thirteen of 21 vessels demonstrated immediate occlusion. All late angiograms have demonstrated complete occlusion of all vessels, with one exception requiring reintervention. One coil migrated from a large CAF and was easily retrieved with a snare. No serious complications occurred. All patients had an uneventful postcatheterization course. CONCLUSIONS: Transcatheter vascular coil embolization with IDCs can be performed safely and effectively in a variety of circumstances.

Experience with the Cardiva Boomerang Catalyst system in pediatric cardiac catheterization.

OBJECTIVES: We studied the safety and efficacy of the Cardiva Boomerang Catalyst vascular closure system in pediatric patients after cardiac catheterization with access in femoral and internal jugular vessels. BACKGROUND: Recurrent catheterization and advances in pediatric interventions increase the need for easy hemostasis without a residual foreign body that may prevent re-accessing the vessel. The Boomerang can be deployed in sheaths as small as 4Fr without residual foreign body, with minimal orientation needed, and few complications reported. METHODS: In a two-month period, all patients between 18 months and 21 years old catheterized with 4-8Fr sheaths less than 15 cm long were eligible for Boomerang placement. These were compared retrospectively with control patients with manual hemostasis. Anthropomorphic measurements, procedure type, activated clotting time, and sheath size as well as total times of cases, intubation, hemostasis, and extubation were compared between the two groups. RESULTS: Forty-six Boomerangs were deployed in 31 patients and compared with 40 patients with manual hemostasis. Boomerangs were deployed in femoral vessels and the internal jugular vein. Device success with hemostasis was achieved in 39 patients (85%). There were no significant differences in time to hemostasis or extubation between the two groups. No major complications or operator error occurred, including hematoma, transfusion, retroperitoneal bleed, infection, vessel occlusion, or need for surgery. CONCLUSIONS: The Boomerang is a safe and easy means of achieving hemostasis in the pediatric population, in femoral vessels as well as internal jugular veins. Its times to hemostasis and extubation were not significantly different from manual hold.

Intra-atrial tissue plasminogen activator infusion for prosthetic valve thrombosis.

Thrombosis is a well-known and life-threatening complication of prosthetic mechanical valves. Therapy typically requires medical thrombolysis or surgical thrombectomy/valve replacement. We report the case of a thrombosed atrioventricular valve in a young boy with complex congenital heart disease, which was successfully treated with direct intra-atrial infusion of recombinant tissue plasminogen activator after failed attempts at systemic therapy. We present this treatment as an alternative to conventional medical therapy.