Blood patch rates after lumbar puncture with Whitacre versus Quincke 22- and 20-gauge spinal needles.

OBJECTIVE: The objective of our study was to compare the incidence of blood patch as the best objective indicator of postdural puncture headache after elective fluoroscopic lumbar puncture with the use of a 22-gauge Whitacre (pencil point) needle versus standard 22- and 20-gauge Quincke (bevel-tip) needles and to determine the best level of puncture. MATERIALS AND METHODS: The records of 724 consecutive patients who were referred to St. Mary's Medical Center department of radiology for fluoroscopic lumbar puncture from January 2003 through April 2007 were retrospectively reviewed. Emergency requests (191) were discarded along with those for patients with clinical signs of pseudotumor cerebri (21), normal pressure hydrocephalus (3), and failed attempts (4). The collective total was 505 elective lumbar punctures. RESULTS: The blood patch rate for the 22-gauge Whitacre needle was 4.2%. The result for the 22-gauge Quincke point needle was 15.1% whereas that for the 20-gauge Quincke point needle was 29.6%. In addition, the level of puncture showed a blood patch rate that increased as the level of lumbar puncture lowered. The highest level of lumbar puncture was L1-L2 with the lowest recorded level being L5-S1. CONCLUSION: The Whitacre needle is associated with a significantly lower incidence of blood patch rate after lumbar puncture. The highest level of puncture (L1-L2) also provides the lowest level of blood patch rate.

Percutaneous imaging-guided solid organ core needle biopsy: coaxial versus noncoaxial method.

OBJECTIVE: The purpose of our study was to compare the diagnostic yield and complication rate of coaxial technique with those of noncoaxial technique in percutaneous imaging-guided renal and hepatic core biopsies. We also compared bleeding complication rates with and without absorbable gelatin sponge occlusion of the biopsy track. MATERIALS AND METHODS: The records of 1,060 consecutively registered patients who underwent percutaneous imaging-guided hepatic or renal biopsy at two hospitals were retrospectively reviewed. Core specimens were obtained in all biopsies. Indications for biopsy included acquisition of general tissue specimens to evaluate for hepatic (n = 495) or renal disease (n = 243) and acquisition of specimens of specific hepatic (n = 289) and renal (n = 33) lesions. Samples were acquired with a coaxial set of needles (n = 764) or with a noncoaxial needle (n = 296 patients). Absorbable gelatin sponge was injected before removal of the outer needle in 269 of the 764 coaxial biopsies. Gelatin sponge was not injected in the other 495 coaxial biopsies. Complication rates were evaluated in a comparison of the two methods and of the coaxial biopsies with and without postprocedural injection of gelatin sponge. Complications were considered minor if follow-up imaging in the 7 days after the procedure showed a complication that did not necessitate treatment other than conservative pain management. Complications were considered major if treatment such as blood product transfusion or surgery was needed or if the patient died. RESULTS: Specimens were immediately given to a pathologist, who typically was present during the procedure. Specimens were evaluated and judged adequate for a specific diagnosis by the histopathology staff. The rates of minor complications were 3.4% (10/296) for the noncoaxial method and 2.6% (20/764) for the coaxial method. The rates of major complications were 1.0% (3/296) for the noncoaxial method and 0.9% (7/764) for the coaxial method. Six cases of major complications necessitating blood product transfusion were documented for the coaxial method and one case for the noncoaxial method. One (0.1%) of the patients undergoing coaxial biopsy died. One patient undergoing noncoaxial biopsy needed surgical repair of an arterial injury that was refractory to blood transfusion, and another developed pancreatitis and needed a blood transfusion. The percentage of minor complications of the coaxial method with absorbable gelatin sponge injection was 3.7% (10/269), and that of major complications was 0.7% (2/269). There was no statistical difference in complication rates between the various methods of percutaneous hepatic and renal biopsy. CONCLUSION: In regard to complications, there are no differences between coaxial and noncoaxial biopsy methods or between the coaxial method with or without injection of absorbable gelatin sponge.

Using pullback pressure measurements to identify venous stenoses persisting after successful angioplasty in failing hemodialysis grafts.

OBJECTIVE: We used pullback pressure measurements to identify venous stenoses persisting after angioplasty of failing hemodialysis grafts. MATERIALS AND METHODS: Fifty angioplasty procedures were performed in 32 patients with elevated venous pressures at dialysis. Grafts were initially evaluated on digital subtraction angiography, and all stenoses measuring greater than 50% on angiography underwent angioplasty. In successful cases (residual stenosis < 30%), pullback pressure measurements were obtained from the superior vena cava to the graft to identify hemodynamically significant (> 10 mm Hg) stenoses. These lesions were then treated with repeated angioplasty. RESULTS: Hemodynamically significant stenoses with a gradient range of 10-27 mm Hg (mean, 16 mm Hg) were found in nine (18%) of 50 procedures. All gradients occurred at sites of previous angioplasty. Repeated angioplasty of these stenoses performed with larger angioplasty balloons reduced gradients to less than 3 mm Hg in six stenoses and to 5 mm Hg in three stenoses. In this subgroup, primary patency was eight (89%) of nine stenoses at 1 month and 2 months and five (56%) of nine stenoses at 6 months. Using life table analysis, we found that primary patency of the entire population was 84% at 1 month, 66% at 2 months, and 47% at 6 months. The mean time between interventions was 6 months, and the thrombosis rate was 0.32 per year. CONCLUSION: Pullback pressure measurements are a useful adjunct to angiography to evaluate the hemodynamic results of angioplasty in patients with failing hemodialysis grafts.