Takayasu arteritis is an idiopathic vasculitis that typically involves the aorta and its major branches. It is more common in women and has the highest prevalence in Asia. Imaging studies are crucial for establishing the diagnosis and for determining the extent of the disease. We present the case of a 47-year-old man who presented with a complaint of anuria and generalized weakness for the last three days. He reported a history of generalized abdominal pain for the last two weeks. His vital signs were within normal limits, but the systolic blood pressure in the lower limb was lower by 60 mmHg compared with that of the upper limb. Notably, the pulses were very faint on palpation. Laboratory investigations revealed deranged renal function parameters. Ultrasound examination showed increased renal parenchymal echogenicity bilaterally with elevated peak systolic velocity of the main renal artery on spectral Doppler. Further investigation by computed tomography demonstrated near-complete thrombosis of the abdominal aorta distal to the origin of the celiac artery and extending to the common iliac arteries with the involvement of bilateral renal arteries. Immunological investigations, including antinuclear antibody (ANA), double-stranded deoxyribonucleic acid (dsDNA), cyclic antineutrophil cytoplasmic antibody (c-ANCA), and perinuclear antineutrophil cytoplasmic antibody (p-ANCA), revealed negative results. However, the positron emission tomography showed markedly diffuse and circumferential increased uptake in the walls of the aorta, subclavian arteries, and femoral arteries. The patient underwent successful endovascular treatment with catheter-directed thrombolysis. High clinical suspicion is required to identify renal artery thrombosis since the clinical symptoms are non-specific. Early diagnosis is crucial to allow for prompt therapeutic interventions.
One of the most common and costly situations in drilling operations is stuck pipe recovery, as it results in significant non-productive time (NPT). Stuck pipe is often freed by applying axial jarring forces to the string to overcome the sticking force. However, becoming stuck at a shallow depth often results in insufficient pipe stretch in the string to generate enough energy to free the stuck pipe using a jar. In cases where it is not applicable to use a jar, the use of the Oscillation Fishing System (OFS) is a more effective technique and an optimal solution to free the stuck pipe. Using the OFS to free stuck pipe encompasses generating continuous oscillatory axial motion. Pressure pulsations generated within the tool are converted to steady axial oscillations using the springs in the tool. This continuous motion produces axial forces at high frequencies, which translates to continuous energy applied to the stuck pipe. The OFS is used in different fishing applications, such as vertical and directional well profiles. The technology is used to free stuck pipes in cased and open holes. Depending on the stuck situation, the OFS is either placed at the surface or downhole with conventional bottom hole assemblies (BHA). In the subject applications, the OFS was run at the surface to free both motor and slick rotary BHAs in large hole sizes, 22 in. and 16 in., in different scenarios. This paper will analyze four examples where the OFS was used in a similar application. In all these examples, conventional stroking tools (i.e., fishing jar) were not part of the system and jars were not used to avoid the potential hazards of impact forces affecting the rig floor. Moreover, activating jars at shallower depths is ineffective as it requires a longer length of pipe to generate enough energy to free the stuck fish. The OFS was used after unsuccessful attempts to pull and recover the string. When the OFS was activated at the surface, producing continuous axial movement, it successfully freed the stuck fish. A new application of the OFS in fishing operations was introduced by using it in the surface sections. Not only did the OFS eliminate the extra steps required to get closer to the stuck point, but also it saved rig time and drillstring components and prevented the need for sidetracking. This paper discusses the use of the OFS at the surface in three examples, including an analysis of the performance to free the stuck string.
Tracheomalacia refers to diffuse or segmental tracheal weakness. Most commonly, tracheomalacia develops after prolonged endotracheal intubation or tracheostomy. Surgical management is warranted in symptomatic patients with severe tracheomalacia. Relief of airway obstruction via stenting often provides immediate improvement in both airflow and symptoms. However, stent placement is associated with significant complications. Here, we present the case of a 71-year-old man who was brought to the emergency department with acute respiratory distress. The patient was known to have tracheomalacia with tracheoesophageal fistula. He had multiple medical comorbidities, including longstanding hypertension, diabetes mellitus, and asthma. The patient had a progressive decline in his level of consciousness and was admitted to the intensive care unit for further management. Despite the maximum ventilatory support, the patient did not achieve an adequate oxygenation level. The patient underwent tracheal stent placement by the interventional radiology team. The insertion was unsuccessful despite three attempts. The tracheal stent had migrated into the upper esophagus on the first and second insertion attempts. Because the patient was unstable to tolerate further attempts, the multidisciplinary team recommended the insertion of an esophageal stent to cover the tracheoesophageal fistula. Despite this, the patient continued to have air leakage with progressive worsening of his respiratory condition as he developed multiorgan failure and died. The management of tracheomalacia in the setting of the tracheoesophageal fistula may pose several challenges. The present case highlights an essential complication of stent placement with the stent migrating into the tracheoesophageal fistula, which is an unusual site of migration. A multidisciplinary approach is crucial in the management of difficult cases of tracheomalacia.
Matrix acid stimulation throughout a well’s life cycle is a common technique applied to wells with impaired productivity. Coiled tubing is often chosen as the conveyance means for delivering the acid treatment in horizontal wells to the damaged zones and in applying effective chemical divergent for highly permeable zones. Due to the nature of helical buckling, weight stacking, and wellbore geometry, the coiled tubing operation is often limited in its ability to reach total depth (TD). In short horizontal wells with slight reservoir contact, conventional methods are used to overcome the effect of drag and friction on the CT; such methods include pumping lubricant fluid. In more challenging applications and extended reach wells (ERW’s), a downhole pulsation tool is placed in the bottomhole assembly to add some axial vibration to the string and exert a pulling force to delay the onset of CT helical buckling, which, in turn, increases the reach of the coil. The significant reduction in friction is caused by the Flow Activated Pulsation Tool (FAPT), which allows the CT to increase its coverage and reach the desired target depth. A new FAPT generation was developed by designing a new valve section to meet the objective of extending the CT reach in highly restricted (2.44") ERW’s. The development of the new valve section was completed after series of testing different valve sections to determine the optimum generated pulses that would increase the overall pull force at the lowest activation flow rate. The newly developed tool offers a stronger and higher performing pulses at lower activation flow rate, allowing it to operate effectively in more challenging ERW’s. The FAPT development and the results of using the new tool after the first two global trial runs. The two wells were drilled as oil producing horizontal wells with +18,000 feet to TD. The wells were completed as open hole with electric submersible pumps (ESP’s) and a 2.44’’ restriction to allow well intervention. In both runs, the goal was achieved by reaching TD of the openhole section with effective placement of the acid treatments.
As the boundaries are pushed with increased length of horizontal wells, coiled tubing (CT) well intervention capabilities are challenged requiring new technologies to expand existing capabilities. When utilizing coiled tubing, standard best practice is to first utilize CT modeling software to optimize CT size and weight for maximum reach. After choosing the right CT size, the next and most critical factor to address in extending the reach is, drag and frictional forces between the CT and the wellbore. Reducing friction and delaying helical buckling will significantly increase the reach. Several versions have been created utilizing various pressure pulse tools in the CT bottom hole assemble (BHA) to accomplish this task. These tools work by creating vibration or pressure pulses that allow for a delay in the onset of the helical buckling of CT and are widely utilized and accepted as solutions. However, existing agitation tool limitations have been reached. A newly designed and developed, hydraulically driven agitation tool (HDAT) to extend CT reach delivers continuous frequency pressure waves along the entire length of the CT. The HDAT provides a reduction in static friction and converts that to a dynamic friction form along the CT string. The continuous hydraulic agitation reduces the onset of helical buckling and thus reduces CT helical contact points, resulting in lower resistance force. The development, design, and lab testing for the HDAT has been through extensive development stages resulting in three generations of the tool, with each version providing an incrementally improved performance. The latest generation HDAT has been designed to function at optimum operational frequencies and produce excitation that works on a longer section of the CT. The performance advancement of the newly designed HDAT generation was achieved after extensive lab testing with a field run reaching a total depth of 24,500 ft over a 4,600 ft open hole lateral section. The new HDAT was redesigned to improve performance and reliability to achieve an effective matrix acid stimulation treatment. The lessons learned from previous generations were imbedded to extend the reach of the CT in the most challenging extended reach wells.
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