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Background/Aims: We surveyed sickle cell disease (SCD) patients who transitioned from pediatric care at Texas Children’s Hematology Center (TCHC) to adult care to determine the characteristics of patients with an adult SCD provider, continuation rates of pre-transition therapies, and patient perceptions of the transition process. Methods: A cross-sectional study was conducted by telephone survey of 44 young adults with SCD, aged 19–29 years, who transitioned from TCHC to adult care within the last 15 years. Results: Findings of the 23-item questionnaire revealed that transitioned patients with current adult providers (68.2%) were more likely to have seen a provider within 6 months of transition (p = 0.023) and to have been on hydroxyurea and/or monthly blood transfusions pre-transition (p = 0.021) than transitioned patients without a provider; 83% of patients on pre-transition hydroxyurea reported continuing hydroxyurea after transition. Transition challenges included inadequate preparation, difficulty finding knowledgeable adult providers, and lack of healthcare insurance/coverage. Conclusion: Transition to adult providers is predicted by establishing care with an adult SCD provider within 6 months of transition and being on pre-transition disease-modifying therapy. Transition may be improved if pediatric hematology centers assist and verify adult provider contact within 6 months of transition and engage patients of all disease severity during transition.

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This paper discusses a relatively new acid-stimulation process that uses dynamic fluid energy to divert flow into a specific fracture point in the well that can initiate and accurately place a hydraulic fracture. These acid-stimulation methods often use two independent fluid streams: the acid phase down the treating string and other liquids or gases down the annulus. The annular fluid may simply serve as a wellbore pressurizing component, or with this process, two different fluids can be mixed downhole with high energy to form a homogenous mixture. Using variations of this process, treatments were performed in four openhole, horizontal wells in the same formation. The first well was acid-fractured with coiled tubing to place many small fractures along the open hole. The second well was acidfractured with coiled tubing, but downhole mixing concepts were also used to provide in-situ generation of CO2 foam where fewer, but larger, fractures were placed in this well. The third and fourth wells were treated with acid using blasting-type rotating or non-rotating jetting tools while mixing the acid with CO2 downhole. Numerous small, near-wellbore fractures were the expected result in these two wells. Experimental laboratory investigation of the physical mechanisms that contributed to these successful stimulations was considered important. Large-scale laboratory tests were performed to more closely examine the physical rock response to the jetting mechanism and conditions. The findings of these tests are presented in this paper. Introduction In an openhole lateral, successful production enhancement treatment depends on identifying the causes of the production deficiency for the specific well to be treated, properly understanding the remedial treatment options available, and evaluating the economics of available options. Assuming the problem is not inadequate reservoir size or recoverable reserves, production deficiencies can result from many factors in a horizontal openhole completion, including: wellbore debris, filter cake or other near-wellbore damage, deeper permeability damage, low formation permeability, or even wellbore location within the reservoir. If the production problem is caused by debris plugging along the lateral, the well can usually be cleaned with an effective hydrablasting and cleaning process. This service generally combines specialized fluid systems (often foams) and possibly a wash tool designed for the different mechanics associated with cleaning deviated or horizontal wellbores. Some processes incorporate computerized design software to properly plan the clean-out operation. If a solids filter-cake has caused near-wellbore damage that is responsible for the production deficiency, an acid wash might be the best solution. Coiled tubing (CT) applications can often allow more efficient washing of the entire lateral or of specific preselected zones. Using tools with jetting nozzles can enhance the effectiveness of acid washes, or even nonreactive fluids that provide the benefits of only mechanical-jetting effects. If deeper damage in the near-wellbore region is decreasing production, an operator may desire to place several small hydraulic fractures at many places along the lateral section to bypass the damage. Such small fractures can use relatively small volumes of acid to give a beneficial result similar to increasing the wellbore diameter, and do so without problems associated with excessive hole enlargement. If the wellbore is located in a poorly producing zone in the reservoir some reasonable distance from a better part of the reservoir, or if a vertical permeability barrier exists, the operator may need to create larger fractures that can communicate the wellbore with more productive zones.

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