Severe failure to thrive (FTT) in a child with asthma and a persistent cough should not be explained solely by asthma and warrants a thorough and prompt evaluation. The finding of a foreign body in ...our case was surprising, because it does not usually present as or lead to FTT. Good clinical judgment and habits could prevent the course of events that we described in this case. Following are the key lessons to be learned from this presentation: (1) maintain a high index of suspicion for foreign body aspiration, even in toddlers with asthma, (2) pay special attention to a child with FTT, (3) be aware of localizing findings on physical examination and chest radiographs, and (4) perform a chest radiograph no later than after 1 month of chronic cough.
Abstract
Hydraulic fracturing is a long-established method of stimulating a well to improve the inflow or outflow potential. Hydraulic fracturing is the most successful stimulation method used by the ...oil and gas industry, and is also used for water injection and production wells around the world, even for drinking-water wells. Hydraulic fracturing creates a crack in the earth that is then filled with a highly conductive material (proppant). This fracture has a large inflow area compared to an unstimulated wellbore and provides a high-permeability path for the fluid to flow in or out of the reservoir.
Hydraulic fracturing has a long history of being used in hot dry rock (HDR) geothermal applications since the 1980s (Murphy & Fehler, 1986). In those often very tight reservoirs, the aim is to create fracture networks that generate the reservoir flow capacity. In high-permeability formations, fracturing can potentially double the productivity of a well. In low-permeability formations, well performance can be increased by a factor of 5–10 in most cases.
In this paper, we focus on two different scenarios of geothermal stimulation. The first is for permeable, porous formations where the heat exchange happens through the perfect contact between the fluid and the porous reservoir. Stimulation may then be necessary to create a small fracture if the pressure drop near the well is too large due to insufficient reservoir permeability. The other scenario is a formation at great depth, where the formation permeability is so extremely small that very long propped fractures would be needed to obtain sufficient flow or even where the porous system does not provide sufficient heat exchange but the heat exchange has to be facilitated by an artificial or stimulated fracture network: a so-called Enhanced Geothermal System.
For porous, permeable formations we will present examples of fracture treatments that can increase the flow rate so that the economics of the project is improved. In some formations, stimulation is then a contingency in case of poorer than expected reservoir quality. A worst-case well with a large skin value of 20 can perform with stimulation like a base-case unstimulated well. In other formations, stimulation will be integral to well design in order to optimise the project performance. For those cases the Coefficient of Performance can be improved from 7 to 25 with the aid of stimulation.
In Ultra-Deep Geothermal (UDG) recovery, the targets are reservoirs below 4000 m, because industrial heat demand requires a minimum temperature of 120°C up to 250°C. For an economic business case, the rate over a period of 15 to 25 years should be from 150 to 450 m
3
h
−1
, depending on the boundary conditions.
Shallower reservoirs in the Netherlands often show very high permeability, but at great depth the target layers could have very low permeability (Veldkamp
et al.
, 2018). Several stimulation methods can be used, of which hydraulic fracture stimulation with water (proppantless) is the primary candidate. Other stimulation methods are propped fracturing in sandstone, acid fracturing in carbonates and thermal stimulation.
For a geological play that is attractive for UDG in the Netherlands, the most likely stimulation method is with water fracturing, because propped fracturing would require a huge amount of proppant that is very costly. Based on analogues and conceptual designs, the expected flow rate is estimated under selected boundary conditions.
Kawasaki disease (KD) is an inflammatory condition of unknown etiology. It involves mainly the skin, mucous membranes, lymph nodes, and myocardium. It may involve the gastrointestinal tract; however, ...it rarely presents as a surgical abdomen. We present a case of a young child with suspected small bowel obstruction who was subsequently diagnosed with KD. We review the surgical presentations of the intestinal tract in KD.
Introduction
This study was designed to compare the occurrences of postoperative cardio-respiratory adverse events during an 8-day follow-up period in the neonatal intensive care unit in small ...infants who underwent elective gastrointestinal surgery under general and combined spinal epidural anesthesia.
Methods
Fifty infants who underwent elective primary gastrointestinal surgery were randomly divided into two anesthetic techniques. General anesthesia (25 patients) and combined spinal-epidural anesthesia (25 patients). The frequency and types of postoperative cardiovascular and respiratory adverse events in the two groups were recorded and compared during an 8-day follow-up period in the neonatal intensive care unit.
Results
The total number of postoperative respiratory adverse events and the number of infants who experienced at least one respiratory adverse event were statistically more in infants anesthetised by general anesthesia than in infants who were anesthetised by combined spinal-epidural anesthesia, respectively (
p
< 0.0001) and (RR = 2.5; 95% CI 1.2–5.3). There were significantly more cardiovascular adverse events in the general anesthesia infants than in the combined spinal-epidural anesthesia (
p
= 0.005). These adverse cardiovascular events were also more resistant to treatment in the general anesthesia infants than in the combined spinal-epidural anesthesia infants (
p
= 0.001).
Conclusion
Compared to general anesthesia, combined spinal-epidural anesthesia reduces the frequency of postoperative respiratory adverse events and improves the postoperative cardiovascular stability in small infants who undergo elective gastrointestinal surgery.
Studies suggest that pediatric onset of Crohn's disease (CD) may demonstrate more frequent upper intestinal and colonic location and in male gender, in comparison to adults. Variability in age of ...onset (AOO) and location of disease have not been adequately explained to date. NOD2/CARD15 is highly expressed in the ileum, while TNF-alpha expression is distributed throughout the gastrointestinal tract. We hypothesized that polymorphisms that affect TNF-alpha function may influence variability of disease location and AOO of CD.
We evaluated two CD cohorts based on AOO (pediatric and adult onset) and 100 ethnically matched healthy controls. Patients were evaluated for AOO, disease location, and genotyped for the presence of polymorphisms in NOD2/CARD15 and in the TNF-alpha promoter region.
Early AOO was associated with male gender, upper intestinal involvement, and a polymorphism in the binding site for NF-kappaB (TNF-863A polymorphism). NOD2 mutations and TNF-863A polymorphism had equivalent but opposite effects on disease location, with a strong combined effect (p= 0.004 corrected for multiple testing). NOD2/CARD15 was associated with ileal involvement, while presence of TNF-863A was inversely associated with ileal disease (OR = 0.42, p= 0.008) and positively associated with isolated colitis (OR = 2.16, p= 0.008, OR = 2.12, p= 0.03 corrected) and familial disease (p= 0.004).
Pediatric onset of CD in our population was associated with a frequent polymorphism in the binding site for NF-kappaB in TNF-alpha promoter but not to defined NOD2/CARD15 disease-associated mutations. This polymorphism is associated with colitis and familial disease. NOD2/CARD15 mutations and the TNF-863C/A polymorphism have equivalent but opposite effects on disease location. These findings may help explain differences in CD phenotype.
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