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We aimed to compare the ability of pulse pressure variation (PPV) to predict fluid responsiveness in prone and supine positions and investigate effect of body mass index (BMI), intraabdominal pressure (IAP) and static respiratory compliance (CS) on PPV. A total of 88 patients undergoing neurosurgery were included. After standardized anesthesia induction, patients' PPV, stroke volume index (SVI), CS and IAP values were recorded in supine (T1) and prone (T2) positions and after fluid loading (T3). Also, PPV change percentage (PPV) between T2 and T1 times was calculated. Patients whose SVI increased more than 15% after the fluid loading were defined as volume responders. In 10 patients, PPV was ≤ - 20%. All of these patients had CS < 31 ml/cmHO, seven had BMI > 30 kg/m, and two had IAP > 15 mmHg. In 16 patients, PPV was ≥ 20%. In these patients, 10 had CS < 31 ml/cmHO, 10 had BMI > 30 kg/m, and 12 had IAP > 15 mmHg. Thirty-nine patients were volume responder. When all patients were examined for predicting fluid responsiveness, area under curves (AUC) of PPV (0.790, 95%CI 0.690-0.870) was significantly lower than AUC of PPV (0.937, 95%CI 0.878-0.997) with ROC analysis (p = 0.002). When patients whose CS was < 31 ml/cmHO and whose BMI was > 30 kg/m were excluded from analysis separately, AUC of PPV became similar to PPV. PPV in the prone can predict fluid responsiveness as good as PPV in the supine, only if BMI is < 30 kg/m and CS value at prone is > 31 ml/cmHO.

Objective:The aim of the present study is to compare the effect of 20% mannitol and 3% NaCl on blood coagulation in vitro using rotational thromboelastometry (ROTEM). Methods:Twenty-millilitre blood samples were obtained from 15 volunteers. In each group, 2 mL blood samples were collected into both polypropylene tubes and EDTA tubes for ROTEM and hemogram analysis. After sampling, blood samples were diluted with test solutions. Group C (control): Only blood, Group M (mannitol): 7% vol 20% mannitol concentration in the blood, Group hypertonic saline (HS): 7% vol 3% hypertonic saline (NaCl) in the blood, Group M/H (mannitol and hydroxyethyl starch solutions [HES]): 6% vol 20% mannitol concentration and 8% vol HES in the blood and Group HS/H (hypertonic saline and HES): 6% vol 3% hypertonic saline concentration and 8% vol HES in the blood. The following thromboelastometric parameters were measured automatically: clotting time (CT) and clot formation time (CFT) with intrinsic activation by tissue factor (InTEM), CT, CFT and maximum clot firmness (MCF) with extrinsic activation by tissue factor (ExTEM) and MCF with FibTEM. Results:The ExTEM CT value was found to be significantly longer in the M/H group than in the controls. The ExTEM CFT median and percentile values were: group C: 85 s (70-95 s), group M: 115 s (94-128 s), group HS: 102 s (84-114 s), group M/H: 128 s (110-144 s) and group HS/H: 118 s (107-132 s). In all the groups, FibTEM MCF values were significantly lower than the control and also there was a significant difference between groups M and HS according to FibTEM MCF values. Conclusion:Whole-blood coagulation disorder induced by these solutions is mainly dependent on fibrinogen and fibrin interaction. However, 3% HS has much less negative effect on coagulation.Keywords: 20% mannitol, 3% NaCl, coagulation, neuroanaesthesia Amaç: Bu çalışmada %20 Manitol ve %3 NaCl'nin in vitro ortamda koagülasyon üzerine etkilerini karşılaştırmayı amaç-ladık.Yöntemler: On beş gönüllünün her birinden 20 mL kan örne-ği alındı. Her grupta rotasyonel tromboelastometri (ROTEM) ve hemogram analizi için 2'şer mL kan örneği polipropilen ve EDTA tüplerinde toplandı. Örnekleme sonrası kan örnekleri test solüsyonları ile seyreltildi. Grup K (Kontrol): sadece kan, Grup M (Mannitol): Kan içinde %7 konsantrasyonda %20 mannitol, Grup hipertonik salin (HS): Kan içinde %7 konsantrasyonda %3 hipertonik salin, Grup M/H (Mannitol ve HES): Kan içinde %7 konsantrasyonda %20 mannitol ve %8 konsantrasyonda HES, Grup HS/H (Hipertonik Salin ve HES): Kan içinde %7 konsantrasyonda %3 hiperetonik salin ve %8 konsantrasyonda HES. Bu işlem sonrası İnTEM'de pıhtılaşma zamanı (PT) ve pıhtı oluşumu zamanı (CFT), ExTEM'de CT, CFT ve maksimum pıhtılaşma zamanı ve FibTEM'de MCF den oluşan thromboelastometri parametreleri otomatik olarak ölçüldü. Bulgular: ExTEM CT değerleri kontrol grubuna göre M/H grubunda önemli ölçüde daha yüksek bulundu. ExTEM CFT medyan ve persentil değerleri şöyledir: C grubu 85S (70-95s), M grubu 115s (94-128s), HS grubu 102S (84-114...

Objective Viral load varies during infection and is higher during the initial stages of disease. Given the importance of the intensive care unit (ICU) in the late stages of COVID-19 infection, analyzing cycle threshold values to detect viral load upon ICU admission can be a clinically valuable tool for identifying patients with the highest mortality risk. Methods This was a retrospectively designed study. Patients older than 18 years who tested positive for SARS-CoV-2 PCR and had a PaO2/FiO2 ratio <200 were included in the study. The patient population was divided into two groups: survivors and non-survivors. Results Two hundred patients were included in the study. In non-survivors, age, relevant ICU admission scores, and procalcitonin levels were significantly higher whereas PaO2/FiO2 ratios and cycle threshold levels were significantly lower than in survivors. Conclusion Viral load at ICU admission has significant prognostic value. In combination with age, comorbidities, and severity scores, viral load may assist clinicians in identifying individuals who need more intensive monitoring. Increased awareness may improve outcomes by allowing the more effective monitoring and treatment of patients. More prospective studies are needed to determine how a high viral load worsens disease and how to avoid irreversible results.