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The use of VRF system and insulation in building envelope are both considered as promising option to reduce energy consumption of a building. This study analysis energy saving potential of VRF system and building insulation using modelling and simulation of a typical office building. The model office building is simulated with the weather of Hyderabad, Sindh, Pakistan using EnergyPlus building simulation software. The simulation cases include conventional and VRF air conditioning systems with and without insulation to evaluate and compare the annual cooling and energy savings and payback period. Results showed that by replacing conventional air conditioner with VRF AC electrical power can be reduced by 42-45%. It is also noted that Cellulose, expanded polystyrene, extruded polystyrene and polyurethane insulations can save around 49.5, 51.4, 51.6, and 54.54% of electricity, respectively. In the case VRF air conditioner used with Cellulose, expanded polystyrene, extruded polystyrene and polyurethane insulation may reduce electricity consumption by 66.5, 67.4, 67.5 and 68.9 %, respectively. The payback period varies from 7 to 15 months. However, cellulose with VRF air conditioner has the least payback period of around 7 months. The longest payback period of around 15 months was noted for the un-insulated office building with VRF air conditioner. Despite having longer payback period, the combination of polyurethane insulation with VRF air conditioning system is the most efficient combination.

The purpose of this study is to assess efficacy of 4-factor prothrombin complex concentrates (4F-PCC) for direct oral anticoagulant (DOAC)-associated intracranial hemorrhage (ICH) as compared to its use in warfarin-associated ICH. A retrospective cohort study was performed to compare the efficacy of 4F-PCC for reversal of apixaban and rivaroxaban versus warfarin for ICH at Cooper University Health Care from January 2015 to December 2019. Patients included were ≥ 18 years of age who developed an ICH while on apixaban, rivaroxaban, or warfarin. The primary outcome was to compare the percentage of patients with Excellent or Good hemostatic efficacy after 4F-PCC administration. Secondary outcomes were to describe functional outcomes at discharge, in-hospital mortality, and thrombotic complications after 4F-PCC administration. A total of 159 patients were included; 115 patients received warfarin and 44 patients received a DOAC (apixaban, n = 22; rivaroxaban, n = 22). 70 patients were evaluable for the primary endpoint. Thirty-four (66.7%) patients in the warfarin group versus 14 (73.7%) patients in the DOAC group were determined to have excellent or good hemostatic efficacy (p = 0.57). In-hospital mortality (30.4% vs. 40.9%, p = 0.21) and thrombotic complications (9.6% vs. 11.4%, p = 0.67) were comparable between the warfarin vs. DOAC groups, respectively. This small, retrospective study found no difference in patients with excellent/good hemostatic efficacy after reversal with 4F-PCC for DOAC-associated ICH compared to warfarin-associated ICH. This study is limited by its retrospective nature and sample size. Larger, prospective studies are needed to further determine the efficacy of 4F-PCC in reversing DOAC-associated ICH.

Chronic subdural hematomas (cSDH) are a common condition encountered by neurosurgeons with the potential for a high morbidity or mortality. A standard treatment regimen still remains highly discussed and controversial. Current treatments include surgical evacuation as well as medical therapies including statins, steroids, and tranexamic acid with ongoing studies to investigate their efficacy. Middle meningeal artery (MMA) embolization is a technique first described in the year 2000, which has shown promising results for cSDH treatment. The procedure is performed in the angiography suite under minimal sedation using embolization materials to block the MMA. This is thought to disrupt the primary blood supply to the cSDH allowing for resolution. Embolization can be utilized as the primary treatment or in addition to surgical evacuation. Current literature suggests that surgically evacuated cSDH can have a recurrence rate from 2% to 37% where the rate after MMA embolization is reported from 2.1% to 4.1%. When used as the primary treatment, MMA embolization can also potentially reduce the morbidity of a surgical procedure under general anesthesia to an elderly patient. Here we present a case of MMA embolization utilized after a postoperative cSDH recurrence with good results.

Introduction: Small studies have suggested that eptifibatide (EPT) may be safe in acute ischemic stroke (AIS) following IV thrombolysis (tPA) or during endovascular therapy (EVT) for large vessel occlusion (LVO), however larger studies are called upon to evaluate the safety of EPT use in this setting. Methods: A stroke center registry (09/2015-12/2020) of consecutive adults who had undergone EVT for LVO was queried. Patients treated with EPT were matched with 3 control groups based on known factors associated with intracranial hemorrhage (ICH) risk - age, early infarct size (Alberta Stroke Program Computed Tomography Scale [ASPECTS] score), and number of thrombectomy passes. ICH, parenchymal hematoma (PH-2), symptomatic ICH (sICH), and 90-day modified Rankin Scale (mRS) score were compared between matched groups. Results: A total of 236 patients were included, 59 of whom (25%) received EPT. IV tPA was non-significantly more utilized in EPT patients (41%, p=0.22). Rate of any ICH was similar between groups (p=0.23), while PH-2 was significantly more frequent with EPT (21% v. 7% v. 3% v. 0%; p= 0.0001). There were no significant differences in sICH (7% EPT v. 7% v. 5% v. 2%; p=0.57), 90-day mRS (p=0.84), or 90-day mortality (p=0.92) between EPT and control groups. Conclusion: In this single center analysis, EPT during EVT was associated with a higher rate of PH-2 grade hemorrhages but not with differences in sICH, 90-day mRS, or 90-day mortality. Larger prospective studies are needed to confirm these findings.

BACKGROUND: Lumbar disc herniation with radiculopathy has a favorable natural history, and a selective nerve root block (SNRB) is an accepted treatment modality. This study aims to ascertain the temporal pattern of pain and disability following the administration of an SNRB in the management of lumbar disc herniation with radiculopathy because there is limited evidence regarding this issue in the published literature. METHODS: This prospective study included 50 patients who underwent an SNRB and were followed for 3 months. Numerical Rating Scale (NRS) for back and leg pain and Oswestry Disability Index (ODI) and Depression Anxiety Stress Scales-21 (DASS-21) scores were collected. At the final follow-up at 3 months, the number of patients who underwent surgery was ascertained. RESULTS: Forty-two of 50 (84%) patients avoided the surgery with a reduction in mean preinjection NRS for back and leg pain from 7.5 (SD 1.33) and 7.7 (SD 1.35) to 3.1 (SD 1.69) and 2.3 (SD 1.14) (P < 0.001), respectively, within the 30 minutes after injection. The pain relief was sustained until the last follow-up. The ODI score also decreased from a mean preinjection level of 59.4 (SD 14.69) to 26.3 (SD 9.43) (P < 0.001) at 3 months. The mean preinjection depression score was higher in patients who had recurrence of pain and eventually underwent surgery. CONCLUSION: Early administration of an SNRB in the course of lumbar radiculopathy is recommended as it provides instantaneous and sustained relief of back and leg pain and disability in a majority of patients. CLINICAL RELEVANCE: SNRB should be administered early in the course of management of lumbar radiculopathy and should not be delayed until after other non-surgical modalities have failed. LEVEL OF EVIDENCE: 2.

The purpose of this study is to assess efficacy of 4-factor prothrombin complex concentrates (4F-PCC) for direct oral anticoagulant (DOAC)-associated intracranial hemorrhage (ICH) as compared to its use in warfarin-associated ICH. A retrospective cohort study was performed to compare the efficacy of 4F-PCC for reversal of apixaban and rivaroxaban versus warfarin for ICH at Cooper University Health Care from January 2015 to December 2019. Patients included were ≥ 18 years of age who developed an ICH while on apixaban, rivaroxaban, or warfarin. The primary outcome was to compare the percentage of patients with Excellent or Good hemostatic efficacy after 4F-PCC administration. Secondary outcomes were to describe functional outcomes at discharge, in-hospital mortality, and thrombotic complications after 4F-PCC administration. A total of 159 patients were included; 115 patients received warfarin and 44 patients received a DOAC (apixaban, n = 22; rivaroxaban, n = 22). 70 patients were evaluable for the primary endpoint. Thirty-four (66.7%) patients in the warfarin group versus 14 (73.7%) patients in the DOAC group were determined to have excellent or good hemostatic efficacy (p = 0.57). In-hospital mortality (30.4% vs. 40.9%, p = 0.21) and thrombotic complications (9.6% vs. 11.4%, p = 0.67) were comparable between the warfarin vs. DOAC groups, respectively. This small, retrospective study found no difference in patients with excellent/good hemostatic efficacy after reversal with 4F-PCC for DOAC-associated ICH compared to warfarin-associated ICH. This study is limited by its retrospective nature and sample size. Larger, prospective studies are needed to further determine the efficacy of 4F-PCC in reversing DOAC-associated ICH.

Neonatal HNT in the pharynx is a rare cause of respiratory distress and poor feeding in the newborn, but must be differentiated from teratoma, encephalocele, and nasal glioma. While surgical resection is the preferred treatment modality, we posit there is a role for sclerosis of the glial heterotopic cyst if complete surgical excision is not possible or carries risk of high morbidity. Here, we present a case of a 7-day-old neonate presenting with acute respiratory distress found to have a nasopharyngeal/oropharyngeal mass ultimately treated with sclerotherapy at 9 months of age.

Delayed cerebral ischemia due to vasospasm following subarachnoid hemorrhage continues to have high morbidity and mortality despite current treatments. This report highlights the use of the Comaneci (Rapid Medical, Yokneam, Israel), a device FDA approved for temporary coil embolization assistance, for the treatment of symptomatic vasospasm. Ten days post subarachnoid hemorrhage, a patient developed acute left-sided hemiparesis with angiographic vasospasm. Through a Headway 17 microcatheter, a Comaneci 17 was deployed in the right ICA terminus, M1, M2, A1, and, A2 segments resulting in improvement of angiographic vasospasm and the patient’s left-sided hemiparesis. On the following day, a repeat angiogram demonstrated no recurrence of vasospasm. The patient had complete return on neurologic function by post bleed day 18 continuing to her four-week follow-up appointment. This case demonstrates the feasibility of the Comaneci device as an effective tool in the treatment of vasospasm following subarachnoid hemorrhage.

Takayasu arteritis (TA) is a rare inflammatory arteritis that is usually affecting young women and causes ischemic changes in the vessel wall. In this report of TA leading to an acute ischemic stroke, we describe a treatment-resistant case, with short interval flares and the challenge of defining the stroke etiology as a large vessel occlusive disease vs. an arteritis flare. We have used CT and MRI modalities to show the active disease and got diagnostic answers from this tool.

We present a case of a 71-year-old male with T12-L1 spondylodiscitis, who was initially treated as a tubercular spondylodiscitis with antituberculous therapy drugs. One month later, the patient developed difficulty in walking with motor weakness in both lower limbs and a second magnetic resonance imaging scan revealed an increase in the volume of pus with cord compression. Pedicle screw stabilization (T9–L4) with T12-L1 laminectomy and curettage of the disc space was performed. Achromobacter denitrificans was identified in aerobic culture. He was treated with an extended course of antibiotics, and subsequently, the lower limb motor power recovered, and biochemical parameters returned to normal. To the best of our knowledge, there has been no report of Achromobacter causing spondylodiscitis in English medical literature. This report focuses on the steps taken in management with special reference to antibiotic therapy.

A 64-year-old man with a previous medical history of hypertension and non-specific focal seizures was admitted for treatment of recurrent anterior communicating artery aneurysm (ACoA). He had previous treatment of the ACoA twice but the aneurysm recanalised again and had grown in size from 1.8 cm

Background Optic nerve sheath diameter (ONSD) has been found to have good correlation with intracranial pressure (ICP) measurements. Here, we aim to determine if the correlation between ONSD and ICP persists throughout the acute phase of neurologic injury through the evaluation of patients with ICP monitoring. We also aim to determine if the ONSD assessments at different depths (3, 6, or 9 mm) and a ratio of the ONSD and eyeball transverse diameter (ETD) are better correlated with ICP than the well-studied ONSD assessment at 3 mm beyond the globe. Methods This retrospective study included 68 patients more than 18 years of age with ICP monitors with both traumatic and spontaneous intracranial injuries. Head computed tomography (CT) scans were reviewed by a radiology resident for assessment of the ETD and ONSD at depths of 3, 6 and 9 mm beyond the globe, and the readings were confirmed by a neuroradiologist. The mean ICP recordings two hours before and after a CT scan were used for assessing the correlation. Results We found that ONSD expansions during the acute phase of neurologic injury were seen even without ICP elevations. This lack of correlation persisted even when different depths of the ONSD assessment or ONSD/ETD ratios were studied. Conclusion This study suggests that ONSD assessment throughout the acute phase may not be a reliable method to monitor ICP. ONSD expansion can persist even after ICP control, and this may be the reason for ONSD expansions seen in our study even with normal ICPs. Further larger size studies are needed to confirm these findings.

An adult Caucasian man with a history of polysubstance abuse was found unresponsive by the nursing staff at his rehabilitation centre and intubated by emergency medical services. On examination, he was stuporous, his eyes did not open to stimulation, his pupils were reactive, localised to pain with bilateral upper extremities and demonstrated triple flexion to noxious stimuli in the bilateral lower extremities. Urine toxicology was positive for cocaine metabolites. A CT scan of the head was performed, which showed possible hypodensities in the bilateral temporal lobes. MRI of the brain was performed to further characterise these hypodensities, and it revealed bilateral middle cerebral artery (MCA) infarction and generalised cerebral …

Background and importance Liposclerosing myxofibrous tumors (LSMFTs) are rare benign fibro-osseous tumors most frequently occurring in the proximal femur. We report the first case of this rare tumor occurring within the calvarium. Clinical presentation Our patient presented with a 2-yr history of enlarging, painless, fixed mass over the left forehead. She underwent surgical resection and the mass was histologically confirmed to be a LSMFT. Conclusion LSMFT is a rare tumor that should remain on the differential for lesions of the calvarium. When diagnosed, this lesion can be removed with the goal of gross total resection and excellent cosmesis can be achieved.

Background: Abdominal pain is one of the most common presenting symptoms in Emergency Department. During a recent audit, it was found that Patients presenting to HGH emergency room with a chief complaint of abdominal pain are the most common patient's category to be delayed to disposition. Currently 62% of patients with abdominal pain admitted to Male Urgent Area in Emergency Department HGH were delayed to Disposition for more than 6 hrs. Aim: To decrease the percentage of patients with abdominal pain delayed in Male Urgent Area ED, HGH for more than 6 hrs from 62% to 50% by May 2015 Project Scope; Project period: February 10th to 24th May 2015; Place: Male Urgent Area, Emergency HGH; Population: Male patients Expected Benefits of the project; Improve Patient Flow; Improve Patient safety; Improve patient Satisfaction. Intervention: All abdominal pain patients must first be reviewed by the consultant of the See & Treat before transfer to male urgent area. Dedicated bed for reassessment of abdominal pain in Male Urgent Area. Flagging of patients when ready for reassessment. Results: Post-intervention length of Stay Male Urgent Area has reduced by 2.28 hrs. Conclusions: Early senior involvement has an impact on decreasing the Length of Stay in abdominal pain patients. Flagging patients for reassessment had an impact on the Length of Stay. It was very challenging to implement the changes and reach out to every staff being a big department. Next steps: Quarterly Audit _ Publication of the Audit _ Continuous Education & Implementing to other Areas of the ED.

The North American unconventional resources energy growth driven by the combination of horizontal drilling, completion tools and hydraulic fracturing innovations has revitalized some conventional plays across the globe that were considered marginal prior to the unconventional boom. This paper presents the workflows utilized to implement unconventional technologies that have resulted in incremental hydrocarbon resources being unlocked. A multi-domain approach is utilized to understand the results from the application of horizontal drilling, completion tools and hydraulic fracturing innovations to the Turner play. High tier log and core data is used initially to create petrophysical and geomechanical models. Numerous petrophysical and geomechanical models are generated based on the uncertainty in model building. Appropriate models are selected based on fracture pressure matching and production history matching techniques. These models are then used to drive the design and optimization process of future offset wells. Characterization of the reservoir (permeability range, pressure and fluid saturations) has led to the understanding that completion techniques used in unconventional plays (slickwater fluid system with tight cluster spacing) cannot be blindly applied. An understanding of fracture geometry and reservoir quality enables changes to be implemented on lateral landing, stage count and job size resulting in incremental production. The importance of reservoir characterization and forward modeling of the application of horizontal technologies is crucial to ensuring efficient allocation of resources to maximize production. This paper showcases the application and evolution of unconventional technologies and workflows to conventional plays to gain incremental production results.

This paper covers the methodology to derive all geomechanical properties (Young's modulus, Poisson's ratio and vertical/horizontal variable Biot constants as a function of rock type) for 13 different stress models. Minimum horizontal stress (Sh) is a key parameter controlling fracture height growth during hydraulic fracturing simulation. Assuming a homogeneous formation (rock property Horizontal:Vertical = 1.0) or poorly derived inputs for the anisotropy model can lead to incorrect fracture geometry. A major assumption made using the various stress models is the Biot poro-elastic constant. Many default models assume a Biot poro-elastic constant of one, which is valid for coarse grained conventional reservoirs where porosity is greater than 20%. Most of the reservoirs stimulated with hydraulic fracturing today do not fall in that porosity range, therefore an alternative derivation for the Biot poro-elasticity and its variability requires additional discussion. Models derived and compared with their associated uncertainties in this paper include: Ben Eaton – isotropic, anisotropic, dynamic and modified with correction factor; default from auto log calibration; Vernik, Jaeger & Cook; Hubbert & Willis; Thiercelin – MC envelope and stiffness tensors (Cij); Segall & Penebaker. The geomechanical properties from the different stress models noted above were inserted into a gridded fracturing simulator. The outputs were compared to actual job and calibration data for; minimum horizontal stress, end of job net pressure and fracture geometry for each of the models. When comparing fracture geometries from each stress model against calibration data it is apparent that the chosen stress model will have a substantial influence on the result. This illustrates the importance of choosing the correct stress model for fracture simulations.

Until 2015, North America’s unconventional resource market was known to be home to the largest oil shale deposits of economic value. Although the recent commodity price fluctuations have exposed the role of geo-politics, world economies and commodity trading on the life cycle of assets, few field development studies have consider the impact of commodity cycles on the development of in-fill wells. Papers have been presented to demonstrate the impact of vertical fracture connectivity and fracture asymmetry on in-fill well performance (due to delayed in-fill drilling), but little has been done on validation and coupling the impact of depletion, due to production, and hydraulic fracturing (due to in-fill efficiency fracture operations). This paper presents results from the analysis of in-fill drilling on well performance. Production data, fracture treatment data, completion and production timing are analyzed using pressure/production history matching techniques and compared with results predicted by data driven models (developed to match well performance) with the aim of proposing in-fill development strategies. Analysis of the field production data indicates that timing of in-fill wells (following the parent well) can influence the in-fill production depending on the level of depletion (cumulative fluid produced) and the size/type of fracture treatments pumped. Analysis of raw production data, modeling results from multi-domain model based coupled simulations and high resolution monitoring data also indicates that the order of the in-fill operations (East-West, Zipper, etc.) also has a significant impact on performance. This paper presents a simplistic approach to understand the impact of the quest for operational efficiencies and economic cycles on development strategies.

When calculating the downhole stresses affecting a wellbore during depletion it has become a standard industry practice to assume only the pore pressure changes, and not the rock mechanical properties. This assumption has the potential to underestimate the total horizontal stress (Sh) causing unrealistic fracture containment. It will also overestimate the effective horizontal stress (Sh' = Sh - Biot * Pore Pressure) for open-hole wellbore failure. High effective horizontal stress assumption can potentially transform rock from brittle to ductile behavior and failure mechanics from shear to compaction and the model becomes overly conservative. Ductile and compaction failure can cause changes in well integrity, as well as changes in fracture geometry from offset infill wells. This paper will document changes in rock properties in the Bakken formation during variable depletion (10% to 65%) and recalculate rock properties (velocities, mechanical properties - Young's modulus, Poisson's ratio, and Biot's anisotropic compressibility constant) as a function of effective stress due to production in order to accurately calculate fracture geometry at an offset well and parent well bore integrity. Hydraulic fracturing simulations are performed to simulate well communication between the fractured well and the depleted parent well along with the potential to re-fracture the parent well using the pore pressure, linear, and non-linear models. Laboratory testing performed on rock samples is shown to validate the non-linear model.

Common complications related to CT-guided percutaneous thoracic bone biopsy procedures include pneumothorax and muscular hematoma. Serious, but rare complications include paralysis, nerve injury, CSF leak, and aortic injury. Device failure has not been well documented in the literature. We discuss our experience with biopsy needle breakage during retrieval of a core specimen and the technique used to help retrieve an embedded needle using a CT fluoroscopic-guided, needle-in-needle approach. A 43 year-old man with Stage IIIa NSCLC was found to have a T11 vertebral body lesion as seen on PET, CT, and MR imaging. The patient underwent a CT-guided biopsy in the prone position. The T11 vertebral body was localized and cannulated using the percutaneous Bonopty® (Apriomed, Upsala, Sweden) needle device. After fine needle aspiration samples were obtained, a core needle biopsy was attempted with a 16-gauge device. The needle fractured 4 cm deep to the skin during removal of a sclerotic lesion, leaving a retained portion within the pedicle and vertebral body. Using CT-guided fluoroscopy, a large diameter Murphy M2 needle was advanced over the distal portion of the fractured Bonopty needle. The Murphy M2 needle was advanced distal to the tip of the Bonopty needle and removed, capturing the broken Bonopty penetration needle along with a core specimen. Larger-bore biopsy needle systems and/or a coaxial system should be used to perform core biopsies in sclerotic lesions to prevent device fracture. If there is device fracture, a larger-bore needle may be used to help capture the fractured needle and prevent open surgery.

A pre-teenager with newly diagnosed ulcerative colitis presented to an emergency department with acute headache, altered mental status and bilateral lower extremity weakness. Head CT demonstrated acute thrombus in the vein of Galen and straight sinus, and the patient was started on a heparin infusion. The patient clinically deteriorated and became unresponsive. In view of the rapid deterioration despite anticoagulation therapy, the patient was taken for endovascular treatment. A novel endovascular approach was performed with combined use of Solitaire FR and Penumbra devices to enhance access to the straight sinus and to limit intraprocedural blood loss. The post-treatment head CT demonstrated a decrease in hyperattenuation within the vein of Galen and straight sinus. The neurologic status improved within 24 h. The patient was discharged home with a normal neurologic examination.

In the current low commodity price environment, several operators have chosen to return to their mature fields to re-fracture the reservoirs to improve overall recovery of reserves. Although modelling remains challenging, re-fracturing treatments have been successfully executed on multiple wells worldwide. This study compares three different approaches to model re-fracturing in tight sands as a means of reducing the overall uncertainty. Multi-domain integration was utilised in which geomechanical data was coupled with petrophysical analysis to build a three-dimensional (3D) hydraulic fracture model. Fracture pressure history matching was performed and the model was validated using calibration data available from microseismic analysis and extended leakoff tests. Production history matching was performed to validate the reservoir simulation model and estimate the resulting depletion around the wellbore. Geomechanical properties and the resulting minimum in-situ horizontal stress were re-calculated incorporating the results of depletion using three different approaches: Pore Pressure Model, Scale Model and Non-Scale Model. Finally, the hydraulic fracture models were re-constructed using the revised geomechanical properties to simulate re-fracturing using various pumping treatments. The fracture geometries obtained from re-fracture simulations were dependent on the model used for re-computation of geomechanical properties post-production as well as the fluid volume pumped. These properties were also validated using laboratory testing. Comparison of the three approaches indicated consistent geometries when small volumes of fluid or typical ‘Plug and Perf’ designs were pumped. Upon pumping larger volumes or typical ‘Sliding Sleeve’ treatments, major differences were observed using the three approaches indicating larger uncertainty and warranting the use of the more rigorous Non-Scale Model. Validated models are important tools for designing hydraulic fracturing treatments to avoid risks of sub-optimisation of fracture designs or undesirable bashing of offset parent wells. Good understanding of re-fracture models helps oil companies make informed decisions regarding their completion programme, hence improving overall hydrocarbon recovery. Modelling of re-fracture treatments continue to pose a challenge for engineers due to added subsurface static and dynamic complexities. This study presents basic guidelines to follow for modelling, with results verified from laboratory testing.