Ilhan Uz - Academia.edu (original) (raw)

Papers by Ilhan Uz

Annals of Medical Research

Aim: To evaluate serum lactate and its clinical utility for disease severity among patients admit... more Aim: To evaluate serum lactate and its clinical utility for disease severity among patients admitted to the emergency department with a diagnosis of diabetic ketoacidosis (DKA). Material and Methods: This is a retrospective data review that included patients ≥18 years of age and admitted to the department with a DKA diagnosis. Patients with a blood glucose level of ≥250 mg/dL between 01 January 2016 to 30 June 2021 with DKA were included. Patients without arterial blood gas or urine ketone analyses, or diagnosed with isolated hyperglycemia were excluded. DKA was defined as a blood glucose level ≥250 mg/dL, pH <7.3, HCO3 <18 mEq/L, and urine ketone positivity at admission. The DKA severity was graded based on the degree of metabolic acidosis based on pH and HCO3 levels. Results: A total of 230 patients were included (82 mild, 126 moderate, and 22 severe DKA). The median age was 44 years, and 50.4% of patients were males. Patient age (p=0.27), sex (p=0.63), and blood glucose lev...

Turkish Journal of Trauma and Emergency Surgery, 2019

Fat embolism syndrome (FES) occurs classically characterized by the combination of acute respirat... more Fat embolism syndrome (FES) occurs classically characterized by the combination of acute respiratory failure, neurologic abnormalities, and a petechial rash. Forty-six-year-old female presented to our emergency department with agitation, altered mental status, and drowsiness. We learned that the patient had received a hyaluronic acid (HA) injection into her buttocks at a beauty center a few hours before her admission. She had no skin findings, but she was hypoxemic. She had lung computed tomography (CT) findings bilateral ground-glass opacities and pleural effusion and had multiple cerebral white lesion on brain magnetic resonance images (MRI). Patients presenting to the emergency department with sudden alteration in mental status should be questioned for recent surgical or invasive aesthetic procedures. Fat embolism syndrome should be considered even if the patient has no petechial rash. Brain MRI and lung CT should be the imaging modality of choice in these patients.

Mediterranean Journal of Infection Microbes and Antimicrobials, 2018

Despite developments in medicine, rabies remains nearly 100% mortal [1,2]. In this paper, we pres... more Despite developments in medicine, rabies remains nearly 100% mortal [1,2]. In this paper, we present a fatal case of rabies in a Syrian refugee who had been bitten by a dog in Syria and developed rabies in Turkey. A 28-year-old Syrian man admitted to the Emergency Service with a 2-day history of shortness of breath, difficulty in swallowing and muscle weakness. He had been living in Turkey as a refugee for three years but had visited Syria three times in the previous 12 months. He had a history of a dog bite on the posterior of his left foot, two months previously in Syria. The patient had killed the dog after being bitten. He had no history of rabies vaccination at the time of the dog bite. However, he had received antibacterial prophylaxis. His neurological examination was also normal except lack of Achilles deep tendon reflex. His laboratory findings were as follows; leukocytes: 5970/mm 3 neutrophils: 71.3% and C-reactive protein: 0.12 mg/dL. Cranial computed tomography and contrast-enhanced cranial magnetic resonance imaging were found to be normal. After 17 hours in the emergency department, the patient attacked the nurses and doctors on duty, who were also immunized with rabies vaccine after the event. Afterwards, the patient was sedated and intubated. Lumbar puncture revealed no leukocyte, protein level of 35 mg/dL and glucose level of 145 mg/dL. Cerebrospinal fluid (CSF) culture and multiplex polymerase chain reaction (PCR) for common viral agents did not show any pathogen. His specimens for rabies (serum, CSF, saliva, nuchal skin biopsy) were sent to Etlik Veterinary Control Central Research Institute, Rabies Diagnosis Laboratory in Ankara for rabies virus diagnostic evaluation. Viral RNA was positive in saliva sample with a RNA concentration of 229.2 ng/µL and with a crossing point value of 29.70 by real time PCR. Viral RNA was negative in CSF with a RNA concentration of 0.1 ng/µL and in nuchal skin biopsy with a RNA concentration of 1.7 ng/µL by real time PCR. No antibody titer was detected in the serum by fluorescent antibody virus neutralization test. Hypotension and pneumonia were detected on his examination after 12 hours and meropenem and linezolid were started. The patient was transferred to the isolation room in the intensive care unit. However, despite all efforts, he had cardiac arrest at the end of 48-h follow-up. After death, the brain sample was

Hong Kong Journal of Emergency Medicine, 2018

Backround: High rates in trauma-related mortality pose a major health problem and increase every ... more Backround: High rates in trauma-related mortality pose a major health problem and increase every day. Early diagnosis and treatment can be lifesavers for this patient group in the emergency departments, which serve as the first place to admit trauma patients in a hospital. Objectives: We aim to determine high-risk criteria to indicate trauma patients getting the most use from whole-body tomography in patients with multiple traumas and reduce unnecessary computed tomography. Methods: We examined retrospectively all electronic files and computed tomography results of patients, who had been admitted to emergency department due to trauma, and who had undergone whole-body computed tomography. Results: We found that possibility of multiple injuries increased by 5.9 times in patients requiring mechanical ventilation. Possibility of multiple injuries in patients with free fluid in the Focused Assessment with Sonography for Trauma increased by 5.6 times. We also observed that possibility of ...

Turkish Journal of Trauma and Emergency Surgery, 2018

BACKGROUND: Trauma is an important health problem in children, and improvement in trauma care on ... more BACKGROUND: Trauma is an important health problem in children, and improvement in trauma care on the national level is possible only through the knowledge gathered from trauma registry systems. This information is not available in our country, because there is no current trauma registry system in the hospitals. Our aim in this paper is to explain the trauma registry system we have developed and to present the first year's data. METHODS: The planned trauma registry system was integrated into the emergency department registry system of 14 hospitals in the Izmir province. The data of pediatric patients with multiple trauma have been recorded automatically through the registry system. Demographics, vital signs, mechanism, the type of trauma, anatomical region, Injury Severity Score (ISS), Pediatric Trauma Score (PTS), Glasgow Coma Scale (GCS) score, the length of hospital stay, and the need for blood transfusion/endotracheal intubation/surgery/ hospitalization were evaluated by the patient transfer status and outcome. RESULTS: At the end of one year, a total of 356 pediatric major trauma patients were included in the study. The most common type of trauma was blunt trauma (91.9%), and the most common mechanism was vehicle-related traffic accident (28.1%). In the group with the Glasgow Outcome Scale ≤3; the age was greater, ISS was higher, and PTS was lower. Motorcycle accidents, sports injuries, and penetrating injuries were more frequent in this group. All scores were significantly different between direct and transferred patients. The referral time to the hospital of the transferred patients was longer than directly admitted patients, but the results were not different. CONCLUSION: Pediatric major trauma is an important cause of mortality and morbidity, and our trauma registry system, which is a successful example abroad, is insufficient in our country. We hope that the trauma registry system we planned and the pilot application we started will be expanded to include other hospitals throughout the country with the aim of developing a national registry system.

The American Journal of Emergency Medicine, 2020

La digestion anaérobie permet la conversion et la valorisation de la matière organique, à l'aide ... more La digestion anaérobie permet la conversion et la valorisation de la matière organique, à l'aide de microorganismes, en énergie sous forme de biogaz, composé de méthane et de dioxyde de carbone, et en un digestat qui peut être utilisé comme amendement organique ou engrais pour les sols. La digestion anaérobie est un procédé complexe, faisant intervenir de nombreuses réactions biologiques sous l'action d'une communauté microbienne complexe. Ces réactions biologiques peuvent être simplifiées en 4 étapes biologiques principales : (1) l'hydrolyse, où la matière organique est hydrolysée en monomères et oligomères solubles, grâce à des enzymes extracellulaires, (2) l'acidogenèse où les acides aminés, les sucres et les acides gras obtenus durant l'hydrolyse sont transformés en acides gras volatils (AGVs) comme l'acétate, en acides organiques et alcools, (3) l'acétogenèse où les AGVs (sauf l'acétate) sont transformés en acétate, en dioxyde de carbone et en hydrogène et (4) la méthanisation où l'acétate, l'hydrogène et le dioxyde de carbone sont transformés en méthane et en dioxyde de carbone. La digestion anaérobie par voie sèche correspond à une teneur en matière sèche de plus de 15%. Ce procédé est à la fois avantageux (diminution de la quantité d'eau et d'énergie nécessaires…) mais avec des inconvénients (hétérogénéité plus importante du milieu et inhibition au-delà de 30% de matière sèche). Cette inhibition serait due à la baisse du transfert interfacial gaz-liquide, ce qui provoquerait une accumulation locale de gaz dissous pouvant être inhibiteurs. L'objectif de cette thèse est donc d'étudier le rôle des gaz dissous dans la digestion anaérobie par voie sèche à l'échelle microscopique et mésoscopique. Une première étude a porté sur les effets des gaz dissous (hydrogène et dioxyde de carbone) à l'échelle locale lors de la digestion anaérobie par voie sèche, sans les effets du transfert de matière (transport diffusif et transfert interfacial gaz-liquide) qui pourraient être limitants. Une deuxième étude a porté sur les effets des gaz dissous à l'échelle mésoscopique lors de la digestion anaérobie par voie sèche, en prenant en compte les effets du transfert de matière. Ainsi, la diminution du transfert interfacial gaz-liquide et l'influence du transport diffusif ont été étudiées ainsi que les effets des accumulations de gaz dissous lors d'une baisse du transfert interfacial gaz-liquide au sein du milieu. Ainsi, à l'échelle microscopique, les expériences ont été réalisées avec un milieu en couche mince afin de tester les effets inhibiteurs des gaz dissous en limitant l'impact du transport diffusif et du transfert interfacial gaz-liquide. Cette étude a permis d'étudier l'impact de l'hydrogène et du dioxyde de carbone sur la digestion anaérobie par voie sèche à l'échelle microscopique. Ainsi, l'hydrogène est un inhibiteur de l'hydrolyse pour la digestion anaérobie par voie sèche à partir de 780 mbars. De plus, le dioxyde de carbone seul accélère la production de méthane sans avoir d'effet sur les autres réactions. L'inhibition de l'hydrolyse par l'hydrogène n'a pas lieu en présence de dioxyde de carbone et est réversible lorsque le dioxyde de carbone est ajouté, avec cependant des effets rémanents inhibiteurs sur la dégradation de l'acétate et la méthanogenèse. A l'échelle mésoscopique, lorsque le transfert interfacial gaz-liquide est limitant et le transport diffusif présent, l'hydrolyse est inhibée, due à la présence d'hydrogène dissous sous forme de gradient de concentration dans le milieu, visible par un gradient de concentrations de métabolites. De plus, l'ajout de dioxyde de carbone lorsque le transfert interfacial gaz-liquide est limitant augmente la concentration en AGVs et baisse le pH, ce qui inhibe la production de méthane. Ainsi, le dioxyde de carbone serait responsable de l'inhibition de la digestion anaérobie lorsque le transfert interfacial gaz-liquide est limitant pour une teneur en matière sèche importante. L'hydrogène et le dioxyde de carbone jouent donc des rôles importants dans le déroulement de la digestion anaérobie par voie sèche, pour des teneurs en matière sèche élevées. MOTS-CLES Digestion anaérobie par voie sèche, transfert de matière, inhibition par l'hydrogène, dioxyde de carbone E.A. Cazier LBE-INRA EXTENTED ABSTRACT: IMPACT OF DISSOLVED GAS ON DRY ANAEROBIC DIGESTION OF LIGNOCELLULOSIC RESIDUES Anaerobic digestion is a way of converting organic matter using microorganisms, into energy as biogas, consisting of CH4 and CO2 and a digestate that can be used as an amendment and fertilizer for soils. Anaerobic digestion is a complex process involving many biological reactions produced by complex microbial communities. The biological reactions can be simplified into 4 main biological steps: (1) hydrolysis, wherein the organic material is hydrolyzed into soluble monomers and oligomers with extracellular enzymes, (2) acidogenesis where the amino acids, sugars and fatty acids obtained during the hydrolysis are converted into volatile fatty acids (VFAs) such as acetate, organic acids and alcohols, (3) acetogenesis where VFAs (except acetate) are converted into acetate, CO2 and H2 and (4) methanization when acetate, H2 and CO2 are converted into CH4 and CO2. Dry anaerobic digestion is defined by a total solid content over 15%. This process is both advantageous (decrease of the need of water and energy) and disadvantageous (higher heterogeneity of the medium and inhibition beyond 30% of total solids). This inhibition is due to the decrease of the gas-liquid transfer, which will increase local concentrations of dissolved gases and may inhibit the anaerobic digestion.

Journal of Academic Emergency Medicine Case Reports, 2013

Turkish Journal of Trauma and Emergency Surgery, 2021

Emergency Physician at Ege University, School of Medicine, Department of Emergency Medicine, 3510... more Emergency Physician at Ege University, School of Medicine, Department of Emergency Medicine, 35100 Izmir, Turkey Assistant Doctor at Ege University, School of Medicine, Department of Emergency Medicine, 35100 Izmir, Turkey Cardiovascular surgeon at Ege University, School of Medicine, Department of Cardiovascular Surgery, 35100 Izmir, Turkey Neursurgeon at Ege University, School of Medicine, Department of Neurosurgery, 35100 Izmir, Turkey Associate Professor of Neurology at Ege University, School of Medicine, Department of Neurology, 35100 Izmir, Turkey Associate Professor of Neuroradiology at Ege University, School of Medicine, Department of Radiology, 35100 Izmir, Turkey Assistant Professor at Ege University, School of Medicine, Department of Emergency Medicine, 35100 Izmir, Turkey

Turkish Journal of Emergency Medicine, 2015

Objectives To compare the differences between conventional radiography and digital computerized r... more Objectives To compare the differences between conventional radiography and digital computerized radiography (CR) in patients presenting to the emergency department. Methods The study enrolled consecutive patients presenting to the emergency department who needed chest radiography. Quality score of the radiogram was assessed with visual analogue score (VAS-100 mm), measured in terms of millimeters and recorded at the end of study. Examination time, interpretation time, total time, and cost of radiograms were calculated. Results There were significant differences between conventional radiography and digital CR groups in terms of location unit (Care Unit, Trauma, Resuscitation), hour of presentation, diagnosis group, examination time, interpretation time, and examination quality. Examination times for conventional radiography and digital CR were 45.2 and 34.2 minutes, respectively. İnterpretation times for conventional radiography and digital CR were 25.2 and 39.7 minutes, respectively. Mean radiography quality scores for conventional radiography and digital CR were 69.1 mm and 82.0 mm. Digital CR had a 1.05 TL cheaper cost per radiogram compared to conventional radiography. Conclusions Since interpretation of digital radiograms is performed via terminals inside the emergency department, the patient has to be left in order to interpret the digital radiograms, which prolongs interpretation times. We think that interpretation of digital radiograms with the help of a mobile device would eliminate these difficulties. Although the initial cost of setup of digital CR and PACS service is high at the emergency department, we think that Digital CR is more cost-effective than conventional radiography for emergency departments in the long-term.

Turkish Journal of Trauma and Emergency Surgery, 2013

We aimed to show the sensitivity of Extended Focused Assessment with Sonography for Trauma (e-FAS... more We aimed to show the sensitivity of Extended Focused Assessment with Sonography for Trauma (e-FAST) for detection of pneumothorax, hemothorax and intraabdominal injury. We also investigated the relationship between e-FAST and need for invasive treatment. METHODS This study included patients who experienced multiple trauma. The emergency physician, who had no clinical information about the patient, performed e-FAST. Findings on a supine chest X-ray and invasive interventions were recorded. The results of abdomen and thorax computed tomography (CT) were reviewed (the size of the pneumothorax was scored). RESULTS Compared with CT, the sensitivities of e-FAST for intraabdominal injury and hemothorax were 54.5% and 71%, respectively. The patients with hemothorax and intraabdominal injuries were not identified with e-FAST, didn't need for invasive intervention. Pneumothorax diagnosis was established in 27 patients with e-FAST (sensitivity 81.8%) from among 33 (30.8%) pneumothorax patients. According to the grading on CT, pneumothoraces less than 1 cm in width and not exceeding the midcoronal line in length were not identified. e-FAST was positive for all patients performed with tube thoracostomy. CONCLUSION e-FAST can be used with high sensitivity for determination of pneumothorax requiring invasive procedure. It has low sensitivity in the diagnosis of intraabdominal injury and hemothorax; however, e-FAST can predict the need for invasive procedures.

Hong Kong Journal of Emergency Medicine

Background: Ventricular assist devices, improve morbidity and survival in patients with end-stage... more Background: Ventricular assist devices, improve morbidity and survival in patients with end-stage heart failure. Objectives: To evaluate the major causes of emergency department admissions in patients with ventricular assist device support. Methods: The charts of 200,000 adult patients who presented to our emergency department between January 2016 and January 2018 were reviewed retrospectively. A total of 444 emergency department visits made by 99 patients with ventricular assist device were included in the study. Results: The annual incidence of emergency department admissions of patients with ventricular assist device was 0.1%. The mean age was 55.5 ± 11.1 years and 85.9% of the study population were men. The most commonly encountered diagnoses were abnormal international normalized ratio or international normalized ratio follow-up (18.2%); heart failure, non-specific chest pain, and chronic obstructive pulmonary disease (15.3%); minor/major bleeding (12.1%); neurological disorder...

Journal of Academic Emergency Medicine Case Reports, 2013

Journal of Academic Emergency Medicine Case Reports, 2013

Annals of Medical Research

Aim: To evaluate serum lactate and its clinical utility for disease severity among patients admit... more Aim: To evaluate serum lactate and its clinical utility for disease severity among patients admitted to the emergency department with a diagnosis of diabetic ketoacidosis (DKA). Material and Methods: This is a retrospective data review that included patients ≥18 years of age and admitted to the department with a DKA diagnosis. Patients with a blood glucose level of ≥250 mg/dL between 01 January 2016 to 30 June 2021 with DKA were included. Patients without arterial blood gas or urine ketone analyses, or diagnosed with isolated hyperglycemia were excluded. DKA was defined as a blood glucose level ≥250 mg/dL, pH <7.3, HCO3 <18 mEq/L, and urine ketone positivity at admission. The DKA severity was graded based on the degree of metabolic acidosis based on pH and HCO3 levels. Results: A total of 230 patients were included (82 mild, 126 moderate, and 22 severe DKA). The median age was 44 years, and 50.4% of patients were males. Patient age (p=0.27), sex (p=0.63), and blood glucose lev...

Turkish Journal of Trauma and Emergency Surgery, 2019

Fat embolism syndrome (FES) occurs classically characterized by the combination of acute respirat... more Fat embolism syndrome (FES) occurs classically characterized by the combination of acute respiratory failure, neurologic abnormalities, and a petechial rash. Forty-six-year-old female presented to our emergency department with agitation, altered mental status, and drowsiness. We learned that the patient had received a hyaluronic acid (HA) injection into her buttocks at a beauty center a few hours before her admission. She had no skin findings, but she was hypoxemic. She had lung computed tomography (CT) findings bilateral ground-glass opacities and pleural effusion and had multiple cerebral white lesion on brain magnetic resonance images (MRI). Patients presenting to the emergency department with sudden alteration in mental status should be questioned for recent surgical or invasive aesthetic procedures. Fat embolism syndrome should be considered even if the patient has no petechial rash. Brain MRI and lung CT should be the imaging modality of choice in these patients.

Mediterranean Journal of Infection Microbes and Antimicrobials, 2018

Despite developments in medicine, rabies remains nearly 100% mortal [1,2]. In this paper, we pres... more Despite developments in medicine, rabies remains nearly 100% mortal [1,2]. In this paper, we present a fatal case of rabies in a Syrian refugee who had been bitten by a dog in Syria and developed rabies in Turkey. A 28-year-old Syrian man admitted to the Emergency Service with a 2-day history of shortness of breath, difficulty in swallowing and muscle weakness. He had been living in Turkey as a refugee for three years but had visited Syria three times in the previous 12 months. He had a history of a dog bite on the posterior of his left foot, two months previously in Syria. The patient had killed the dog after being bitten. He had no history of rabies vaccination at the time of the dog bite. However, he had received antibacterial prophylaxis. His neurological examination was also normal except lack of Achilles deep tendon reflex. His laboratory findings were as follows; leukocytes: 5970/mm 3 neutrophils: 71.3% and C-reactive protein: 0.12 mg/dL. Cranial computed tomography and contrast-enhanced cranial magnetic resonance imaging were found to be normal. After 17 hours in the emergency department, the patient attacked the nurses and doctors on duty, who were also immunized with rabies vaccine after the event. Afterwards, the patient was sedated and intubated. Lumbar puncture revealed no leukocyte, protein level of 35 mg/dL and glucose level of 145 mg/dL. Cerebrospinal fluid (CSF) culture and multiplex polymerase chain reaction (PCR) for common viral agents did not show any pathogen. His specimens for rabies (serum, CSF, saliva, nuchal skin biopsy) were sent to Etlik Veterinary Control Central Research Institute, Rabies Diagnosis Laboratory in Ankara for rabies virus diagnostic evaluation. Viral RNA was positive in saliva sample with a RNA concentration of 229.2 ng/µL and with a crossing point value of 29.70 by real time PCR. Viral RNA was negative in CSF with a RNA concentration of 0.1 ng/µL and in nuchal skin biopsy with a RNA concentration of 1.7 ng/µL by real time PCR. No antibody titer was detected in the serum by fluorescent antibody virus neutralization test. Hypotension and pneumonia were detected on his examination after 12 hours and meropenem and linezolid were started. The patient was transferred to the isolation room in the intensive care unit. However, despite all efforts, he had cardiac arrest at the end of 48-h follow-up. After death, the brain sample was

Hong Kong Journal of Emergency Medicine, 2018

Backround: High rates in trauma-related mortality pose a major health problem and increase every ... more Backround: High rates in trauma-related mortality pose a major health problem and increase every day. Early diagnosis and treatment can be lifesavers for this patient group in the emergency departments, which serve as the first place to admit trauma patients in a hospital. Objectives: We aim to determine high-risk criteria to indicate trauma patients getting the most use from whole-body tomography in patients with multiple traumas and reduce unnecessary computed tomography. Methods: We examined retrospectively all electronic files and computed tomography results of patients, who had been admitted to emergency department due to trauma, and who had undergone whole-body computed tomography. Results: We found that possibility of multiple injuries increased by 5.9 times in patients requiring mechanical ventilation. Possibility of multiple injuries in patients with free fluid in the Focused Assessment with Sonography for Trauma increased by 5.6 times. We also observed that possibility of ...

Turkish Journal of Trauma and Emergency Surgery, 2018

BACKGROUND: Trauma is an important health problem in children, and improvement in trauma care on ... more BACKGROUND: Trauma is an important health problem in children, and improvement in trauma care on the national level is possible only through the knowledge gathered from trauma registry systems. This information is not available in our country, because there is no current trauma registry system in the hospitals. Our aim in this paper is to explain the trauma registry system we have developed and to present the first year's data. METHODS: The planned trauma registry system was integrated into the emergency department registry system of 14 hospitals in the Izmir province. The data of pediatric patients with multiple trauma have been recorded automatically through the registry system. Demographics, vital signs, mechanism, the type of trauma, anatomical region, Injury Severity Score (ISS), Pediatric Trauma Score (PTS), Glasgow Coma Scale (GCS) score, the length of hospital stay, and the need for blood transfusion/endotracheal intubation/surgery/ hospitalization were evaluated by the patient transfer status and outcome. RESULTS: At the end of one year, a total of 356 pediatric major trauma patients were included in the study. The most common type of trauma was blunt trauma (91.9%), and the most common mechanism was vehicle-related traffic accident (28.1%). In the group with the Glasgow Outcome Scale ≤3; the age was greater, ISS was higher, and PTS was lower. Motorcycle accidents, sports injuries, and penetrating injuries were more frequent in this group. All scores were significantly different between direct and transferred patients. The referral time to the hospital of the transferred patients was longer than directly admitted patients, but the results were not different. CONCLUSION: Pediatric major trauma is an important cause of mortality and morbidity, and our trauma registry system, which is a successful example abroad, is insufficient in our country. We hope that the trauma registry system we planned and the pilot application we started will be expanded to include other hospitals throughout the country with the aim of developing a national registry system.

The American Journal of Emergency Medicine, 2020

La digestion anaérobie permet la conversion et la valorisation de la matière organique, à l'aide ... more La digestion anaérobie permet la conversion et la valorisation de la matière organique, à l'aide de microorganismes, en énergie sous forme de biogaz, composé de méthane et de dioxyde de carbone, et en un digestat qui peut être utilisé comme amendement organique ou engrais pour les sols. La digestion anaérobie est un procédé complexe, faisant intervenir de nombreuses réactions biologiques sous l'action d'une communauté microbienne complexe. Ces réactions biologiques peuvent être simplifiées en 4 étapes biologiques principales : (1) l'hydrolyse, où la matière organique est hydrolysée en monomères et oligomères solubles, grâce à des enzymes extracellulaires, (2) l'acidogenèse où les acides aminés, les sucres et les acides gras obtenus durant l'hydrolyse sont transformés en acides gras volatils (AGVs) comme l'acétate, en acides organiques et alcools, (3) l'acétogenèse où les AGVs (sauf l'acétate) sont transformés en acétate, en dioxyde de carbone et en hydrogène et (4) la méthanisation où l'acétate, l'hydrogène et le dioxyde de carbone sont transformés en méthane et en dioxyde de carbone. La digestion anaérobie par voie sèche correspond à une teneur en matière sèche de plus de 15%. Ce procédé est à la fois avantageux (diminution de la quantité d'eau et d'énergie nécessaires…) mais avec des inconvénients (hétérogénéité plus importante du milieu et inhibition au-delà de 30% de matière sèche). Cette inhibition serait due à la baisse du transfert interfacial gaz-liquide, ce qui provoquerait une accumulation locale de gaz dissous pouvant être inhibiteurs. L'objectif de cette thèse est donc d'étudier le rôle des gaz dissous dans la digestion anaérobie par voie sèche à l'échelle microscopique et mésoscopique. Une première étude a porté sur les effets des gaz dissous (hydrogène et dioxyde de carbone) à l'échelle locale lors de la digestion anaérobie par voie sèche, sans les effets du transfert de matière (transport diffusif et transfert interfacial gaz-liquide) qui pourraient être limitants. Une deuxième étude a porté sur les effets des gaz dissous à l'échelle mésoscopique lors de la digestion anaérobie par voie sèche, en prenant en compte les effets du transfert de matière. Ainsi, la diminution du transfert interfacial gaz-liquide et l'influence du transport diffusif ont été étudiées ainsi que les effets des accumulations de gaz dissous lors d'une baisse du transfert interfacial gaz-liquide au sein du milieu. Ainsi, à l'échelle microscopique, les expériences ont été réalisées avec un milieu en couche mince afin de tester les effets inhibiteurs des gaz dissous en limitant l'impact du transport diffusif et du transfert interfacial gaz-liquide. Cette étude a permis d'étudier l'impact de l'hydrogène et du dioxyde de carbone sur la digestion anaérobie par voie sèche à l'échelle microscopique. Ainsi, l'hydrogène est un inhibiteur de l'hydrolyse pour la digestion anaérobie par voie sèche à partir de 780 mbars. De plus, le dioxyde de carbone seul accélère la production de méthane sans avoir d'effet sur les autres réactions. L'inhibition de l'hydrolyse par l'hydrogène n'a pas lieu en présence de dioxyde de carbone et est réversible lorsque le dioxyde de carbone est ajouté, avec cependant des effets rémanents inhibiteurs sur la dégradation de l'acétate et la méthanogenèse. A l'échelle mésoscopique, lorsque le transfert interfacial gaz-liquide est limitant et le transport diffusif présent, l'hydrolyse est inhibée, due à la présence d'hydrogène dissous sous forme de gradient de concentration dans le milieu, visible par un gradient de concentrations de métabolites. De plus, l'ajout de dioxyde de carbone lorsque le transfert interfacial gaz-liquide est limitant augmente la concentration en AGVs et baisse le pH, ce qui inhibe la production de méthane. Ainsi, le dioxyde de carbone serait responsable de l'inhibition de la digestion anaérobie lorsque le transfert interfacial gaz-liquide est limitant pour une teneur en matière sèche importante. L'hydrogène et le dioxyde de carbone jouent donc des rôles importants dans le déroulement de la digestion anaérobie par voie sèche, pour des teneurs en matière sèche élevées. MOTS-CLES Digestion anaérobie par voie sèche, transfert de matière, inhibition par l'hydrogène, dioxyde de carbone E.A. Cazier LBE-INRA EXTENTED ABSTRACT: IMPACT OF DISSOLVED GAS ON DRY ANAEROBIC DIGESTION OF LIGNOCELLULOSIC RESIDUES Anaerobic digestion is a way of converting organic matter using microorganisms, into energy as biogas, consisting of CH4 and CO2 and a digestate that can be used as an amendment and fertilizer for soils. Anaerobic digestion is a complex process involving many biological reactions produced by complex microbial communities. The biological reactions can be simplified into 4 main biological steps: (1) hydrolysis, wherein the organic material is hydrolyzed into soluble monomers and oligomers with extracellular enzymes, (2) acidogenesis where the amino acids, sugars and fatty acids obtained during the hydrolysis are converted into volatile fatty acids (VFAs) such as acetate, organic acids and alcohols, (3) acetogenesis where VFAs (except acetate) are converted into acetate, CO2 and H2 and (4) methanization when acetate, H2 and CO2 are converted into CH4 and CO2. Dry anaerobic digestion is defined by a total solid content over 15%. This process is both advantageous (decrease of the need of water and energy) and disadvantageous (higher heterogeneity of the medium and inhibition beyond 30% of total solids). This inhibition is due to the decrease of the gas-liquid transfer, which will increase local concentrations of dissolved gases and may inhibit the anaerobic digestion.

Journal of Academic Emergency Medicine Case Reports, 2013

Turkish Journal of Trauma and Emergency Surgery, 2021

Emergency Physician at Ege University, School of Medicine, Department of Emergency Medicine, 3510... more Emergency Physician at Ege University, School of Medicine, Department of Emergency Medicine, 35100 Izmir, Turkey Assistant Doctor at Ege University, School of Medicine, Department of Emergency Medicine, 35100 Izmir, Turkey Cardiovascular surgeon at Ege University, School of Medicine, Department of Cardiovascular Surgery, 35100 Izmir, Turkey Neursurgeon at Ege University, School of Medicine, Department of Neurosurgery, 35100 Izmir, Turkey Associate Professor of Neurology at Ege University, School of Medicine, Department of Neurology, 35100 Izmir, Turkey Associate Professor of Neuroradiology at Ege University, School of Medicine, Department of Radiology, 35100 Izmir, Turkey Assistant Professor at Ege University, School of Medicine, Department of Emergency Medicine, 35100 Izmir, Turkey

Turkish Journal of Emergency Medicine, 2015

Objectives To compare the differences between conventional radiography and digital computerized r... more Objectives To compare the differences between conventional radiography and digital computerized radiography (CR) in patients presenting to the emergency department. Methods The study enrolled consecutive patients presenting to the emergency department who needed chest radiography. Quality score of the radiogram was assessed with visual analogue score (VAS-100 mm), measured in terms of millimeters and recorded at the end of study. Examination time, interpretation time, total time, and cost of radiograms were calculated. Results There were significant differences between conventional radiography and digital CR groups in terms of location unit (Care Unit, Trauma, Resuscitation), hour of presentation, diagnosis group, examination time, interpretation time, and examination quality. Examination times for conventional radiography and digital CR were 45.2 and 34.2 minutes, respectively. İnterpretation times for conventional radiography and digital CR were 25.2 and 39.7 minutes, respectively. Mean radiography quality scores for conventional radiography and digital CR were 69.1 mm and 82.0 mm. Digital CR had a 1.05 TL cheaper cost per radiogram compared to conventional radiography. Conclusions Since interpretation of digital radiograms is performed via terminals inside the emergency department, the patient has to be left in order to interpret the digital radiograms, which prolongs interpretation times. We think that interpretation of digital radiograms with the help of a mobile device would eliminate these difficulties. Although the initial cost of setup of digital CR and PACS service is high at the emergency department, we think that Digital CR is more cost-effective than conventional radiography for emergency departments in the long-term.

Turkish Journal of Trauma and Emergency Surgery, 2013

We aimed to show the sensitivity of Extended Focused Assessment with Sonography for Trauma (e-FAS... more We aimed to show the sensitivity of Extended Focused Assessment with Sonography for Trauma (e-FAST) for detection of pneumothorax, hemothorax and intraabdominal injury. We also investigated the relationship between e-FAST and need for invasive treatment. METHODS This study included patients who experienced multiple trauma. The emergency physician, who had no clinical information about the patient, performed e-FAST. Findings on a supine chest X-ray and invasive interventions were recorded. The results of abdomen and thorax computed tomography (CT) were reviewed (the size of the pneumothorax was scored). RESULTS Compared with CT, the sensitivities of e-FAST for intraabdominal injury and hemothorax were 54.5% and 71%, respectively. The patients with hemothorax and intraabdominal injuries were not identified with e-FAST, didn't need for invasive intervention. Pneumothorax diagnosis was established in 27 patients with e-FAST (sensitivity 81.8%) from among 33 (30.8%) pneumothorax patients. According to the grading on CT, pneumothoraces less than 1 cm in width and not exceeding the midcoronal line in length were not identified. e-FAST was positive for all patients performed with tube thoracostomy. CONCLUSION e-FAST can be used with high sensitivity for determination of pneumothorax requiring invasive procedure. It has low sensitivity in the diagnosis of intraabdominal injury and hemothorax; however, e-FAST can predict the need for invasive procedures.

Hong Kong Journal of Emergency Medicine

Background: Ventricular assist devices, improve morbidity and survival in patients with end-stage... more Background: Ventricular assist devices, improve morbidity and survival in patients with end-stage heart failure. Objectives: To evaluate the major causes of emergency department admissions in patients with ventricular assist device support. Methods: The charts of 200,000 adult patients who presented to our emergency department between January 2016 and January 2018 were reviewed retrospectively. A total of 444 emergency department visits made by 99 patients with ventricular assist device were included in the study. Results: The annual incidence of emergency department admissions of patients with ventricular assist device was 0.1%. The mean age was 55.5 ± 11.1 years and 85.9% of the study population were men. The most commonly encountered diagnoses were abnormal international normalized ratio or international normalized ratio follow-up (18.2%); heart failure, non-specific chest pain, and chronic obstructive pulmonary disease (15.3%); minor/major bleeding (12.1%); neurological disorder...

Journal of Academic Emergency Medicine Case Reports, 2013

Journal of Academic Emergency Medicine Case Reports, 2013