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Dive into the research topics where Hakan Güven is active.

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Featured researches published by Hakan Güven.


Clinical Toxicology | 2002

Serum acetylcholinesterase and prognosis of acute organophosphate poisoning

Dursun Aygün; Zahide Doganay; Levent Altintop; Hakan Güven; Musa Onar; Turgut Deniz; Tevfik Sunter

Objective: The aim of this study is to investigate the prognostic value of serum acetylcholinesterase levels and their relationship with neurological syndromes (Type 1 syndrome, intermediate syndrome, and delayed polyneuropathy) in acute organophosphate poisoning. Materials and methods: Thirty-two consecutive patients with acute organophosphate poisoning admitted to the Ondokuz Mayis University Emergency Department from June 1999 to January 2001 were evaluated. Patients were assessed according to admission time, symptoms, and results of clinical exams and their serum acetylcholinesterase levels were determined on days 1, 2, 3, 7, and the last day. Results: There was no significant difference between the first-day serum acetylcholinesterase of the patients with severe poisoning (n=22, 68.75%) and of the patients with mild poisoning (n=10, 31.25%; NS). There was no discernible difference between the serum acetylcholinesterase obtained on days 1 and 3 after poisoning from the patients with intermediate syndrome (n=5, 15.6%; means: 0.90±0.65 vs. 0.88±0.53, 19.35 vs. 18.92%; NS, sensitivity=80%; specificity=87.5%). There was a significant difference between the serum acetylcholinesterase obtained on days 1 and 3 from the patients with nonintermediate syndrome (n=24, 75%; means: 1.05±0.24 vs. 1.68±0.29, 22.58 vs. 36.12%; p<0.001). There was no discernible significant difference in serum acetylcholinesterase between the patients with organophosphorus-induced delayed polyneuropathy (n=7, 21.8%) and nonorganophosphorus-induced delayed polyneuropathy. In the patients who died (n=5, 15.6%), serum acetylcholinesterase showed no discernible increase day 1–the last day (means: 0.50±0.25 vs. 0.46±0.26, 10.75 vs. 9.89%; NS). There was a significant difference between the serum acetylcholinesterase levels obtained on days 1 and the last day from the patients who survived (n=27, 84.3%; means: 1.14±0.25 vs. 2.32±0.26, 24.51 vs. 49.89%; p<0.001). Conclusion: In the acute phase of organophosphate poisoning, low serum acetylcholinesterase (>50% of minimum normal value) supports the diagnosis of organophosphate poisoning but it does not show a significant relationship to the severity of poisoning (NS). The serum acetylcholinesterase activity may be a useful parameter in following the acute prognosis of organophosphate poisoning.


American Journal of Emergency Medicine | 2003

Anticoagulant-induced intramural intestinal hematoma

Cafer Polat; Adem Dervisoglu; Hakan Güven; Ekrem Kaya; Zafer Malazgirt; Murat Danaci; Kayhan Ozkan

Intramural hematoma of the intestine is a rare complication of anticoagulant therapy. We evaluated 7 nontrauma patients with intramural hematoma of the intestine diagnosed at our institution between May 1998 and June 2001. All of the patients were receiving long-term anticoagulant therapy for previous diseases. All 7 patients had abdominal pain, 6 had additional symptoms of nausea and vomiting, and 4 had melanotic stools at admission. Six of the patients had abnormal coagulation parameters. Both abdominal ultrasonography (US) and computerized tomography (CT) showed the exact pathology in all patients. Five of the 7 patients were treated, nonoperatively, and the other patients underwent surgery. All of the patients were followed with abdominal US and CT (mean 12 = months), with complete resolution of their intramural hematomas. Abdominal US and CT evaluation performed together will help the accuracy of diagnosis of intramural hematoma, but nonoperative therapy is the treatment of choice, with surgery indicated if generalized peritonitis or intestinal obstruction develops.


American Journal of Emergency Medicine | 2003

Climatic and diurnal variation in suicide attempts in the ED

Zahide Doganay; A.Tevfik Sunter; Hatice Guz; Aysen Ozkan; Levent Altintop; Celal Kati; Esra Colak; Dursun Aygün; Hakan Güven

The aim of this study was to determine whether there is a relationship between climatic factors and suicidal behavior. A total of 1,119 suicide attempts were collected from hospital records between 1996 and 2001. A clear seasonal variation was seen in suicide attempts in the 15-24, 25-34, and over 65 age groups in men and in the 15-24, 25-34, and 35-44 age groups in women with peaks in the spring and summer. Suicide attempts were more frequent between the hours of 6:00-9:00 pm in males and 3:00-6:00 pm in females. People attempting suicide who have depression, anxiety, or a psychotic disorder usually attempt suicide in the summer. Whereas the monthly averages of humidity, ambient temperature, duration and intensity of sunlight were positively correlated with the number of monthly suicide attempts, cloudiness and atmospheric pressure were negatively correlated. In conclusion, we must keep in mind that suicides and suicide attempts are not only the effect of climatic changes and that the most important component is the individuals ability to deal with conflicts.


Human & Experimental Toxicology | 2002

Basic toxicological approach has been effective in two poisoned patients with amitraz ingestion: case reports

Zahide Doganay; Dursun Aygün; L Altintop; Hakan Güven; Fikret Bildik

Amitraz, a formamidine insecticide and acaricide used in veterinary practice, presents side effects in humans related to its pharmacological activity on alpha 2-adrenergic receptors. There is little information available in the literature about the toxicology of the product in man and the treatment of this poisoning. In this report, the clinical and laboratory features of amitraz poisoning in two patients by a veterinary formulation also containing xylene are presented. The major clinical findings were unconsciousness, drowsiness, respiratory failure requiring mechanical ventilation, miosis, hypothermia and brady cardia. The laboratory findings were hyperglycemia, hypertransaminasemia and increased urinary output. Supportive management of this poisoning in humans is suggested in only a few articles and there is no specific antidote for the subsequent possible pharmacological effects of amitraz. In our two cases, we performed supportive treatment such as mechanical ventilation, atropine, gastric lavage, active carbon, oxygen and fluid administration. We concluded that the basic approach to the patient with amitraz poisoning, including initial stabilization to correct immediate life-threatening problems, treatment to reduce absorption and measures to improve elimination of the toxin, is effective.


Journal of Trauma-injury Infection and Critical Care | 2002

Moderate Hypothermia Prevents Brain Stem Oxidative Stress Injury after Hemorrhagic Shock

Hakan Güven; Ramazan Amanvermez; Zafer Malazgirt; Ekrem Kaya; Zahide Doganay; Cemil Çelik; Kayhan Ozkan

BACKGROUND The purpose of this study was to investigate the effects of temperature on oxidative stress in brain stem tissue induced by hemorrhagic shock. We researched the hemorrhagic oxidative stress at various core temperatures using reduced glutathione (GSH) levels and thiobarbituric acid-reactive substances (TBARS) as markers of lipid peroxidation in brain stem homogenate. METHODS Forty rats were divided into four groups, of which one constituted the nonbleeding normothermia control group. In all of the three study groups, 40% of estimated blood volume was removed while they were being held at normothermia, mild hypothermia (32 degrees C), or moderate hypothermia (28 degrees C). Parameters including mean arterial pressure, rectal temperature, and heart and breathing rates were monitored and recorded during the procedures. After an hour at shock state, tissue samples were removed by craniectomy. RESULTS The tissue levels of TBARS increased significantly in normothermic and mild hypothermic hemorrhagic shock groups (10.74 nmol/g and 8.26 nmol/g) as compared with the control group (3.50 nmol/g) (p < 0.001). However, the tissue TBARS level in the moderate hypothermia group was only minimally increased (4.53 nmol/g). GSH showed a slight decrease in normothermic and mild hypothermic bleeding rats, and were unchanged in the moderate hypothermic rats. CONCLUSION Moderate systemic hypothermia (28 degrees C) appears to protect brain stem tissue from oxidative stress during severe hemorrhagic shock in rats, as indicated by insignificant change in tissue TBARS and GSH concentrations. These results suggest antioxidant protective effects of moderate systemic hypothermia in metabolically active brain stem tissue during hemorrhagic shock. Similar effects in humans remain to be studied.


Headache | 2003

Electrocardiographic changes during migraine attacks.

Dursun Aygün; Levent Altintop; Zahide Doganay; Hakan Güven; Ahmet Baydin

Objectives.—To clarify whether electrocardiographic (ECG) changes can be identified during a migraine attack and to determine whether there are ECG differences between periods with and without headache.


Journal of Intensive Care Medicine | 2005

In acute organophosphate poisoning, the efficacy of hemoperfusion on clinical status and mortality.

Levent Altintop; Dursun Aygün; Havva Sahin; Zahide Doganay; Hakan Güven; Yüksel Bek; Tekin Akpolat

The aims of this study were to report experience in patients with organophosphate poisoning (OPP) and to discuss the potential role for hemoperfusion (HP) in the management of severe OPP. At the emergency service of a university hospital, 52 patients with acute OPP were included in this retrospective study. The patients were divided into 2 groups (Group 1, severe poisoning, n = 25; and Group 2, mild poisoning, n = 27). All patients with mild OPP survived. Seven patients (28%) of the 25 with severe OPP died. This study supports previous data documenting that HP is unnecessary in the management of mild OPP. Although there was not a control group (severe poisoning without HP treatment) in this study, experience suggests that HP can be useful in severe cases. Reports from centers having experience with severe OPP can help clarify this controversial issue. Randomized controlled (prospective) studies investigating the possible beneficial effects of HP on patient survival in patients with severe OPP with control group are needed.


International Journal of Clinical Practice | 2007

B‐type natriuretic peptide as an indicator of right ventricular dysfunction in acute pulmonary embolism*

Türker Yardan; Levent Altintop; Ahmet Baydin; Ozcan Yilmaz; Hakan Güven

Objective:  B‐type natriuretic peptide (BNP) is a neurohormone secreted from cardiac ventricles in response to ventricular strain. The aim of present study was to evaluate the role of BNP in the diagnosis of the right ventricular (RV) dysfunction in acute pulmonary embolism (PE).


Emergency Medicine Journal | 2005

Acute aortic dissection provoked by sneeze: a case report

Ahmet Baydin; M S Nural; Hakan Güven; T Deniz; Fikret Bildik; A Karaduman

The response of the abdominal viscera and the contraction of the intercostal muscles during the respiratory phase of sneezing increases intrathoracic pressure, which may lead to several complications. However, there are no reports in the literature concerning aortic dissection after sneezing. We report a patient in whom the development of dissection was secondary to sneezing, although hypertension was present as a risk factor, and we discuss the relationship between sneezing and aortic dissection. To our knowledge, this is the first report of aortic dissection provoked by sneezing in the literature.


Clinical Neurology and Neurosurgery | 2005

Posttraumatic pneumocephalus-induced bilateral oculomotor nerve palsy

Dursun Aygün; Zahide Doganay; Ahmet Baydin; Murat Akyol; Alparslan Senel; M. Selim Nural; Yavuz Otal; Hakan Güven

Bilateral third nerve palsy often points to the involvement of its nucleus. Third nerve palsy as a result of posttraumatic nuclear involvement is an extremely rare condition. A 23-year-old man presented with a depressed skull fracture after acute head trauma and had Glasgow Coma Scale Score of 9. The diameters of the pupils were 6.5 and 7.5 mm and they were not reactive to light stimulation. There was bilateral ptosis. Computed tomography (CT) relieved bilateral perimesensephalic pneumocephalus. We suggested that bilateral oculomotor nerve paresis might develop in association with posttraumatic bilateral perimesensephalic pneumocephalus, which affected the nucleus of the third nerve.

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Dursun Aygün

Ondokuz Mayıs University

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Levent Altintop

Ondokuz Mayıs University

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Zahide Doganay

Ondokuz Mayıs University

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Ahmet Baydin

Ondokuz Mayıs University

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Adem Dervisoglu

Ondokuz Mayıs University

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Cafer Polat

Ondokuz Mayıs University

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Murat Hokelek

Ondokuz Mayıs University

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