Novel parameters for predicting fluid responsiveness during the mini fluid challenge and ability of the cardiac power index: an observational cohort study.

Background/aim: The percentage change in the stroke volume index (SVI) due to the mini fluid challenge (MFC) (MFC-ΔSVI%) is used commonly in daily practice. However, up to 20% of patients remain in the gray zone of this variable. Thus, it was aimed to compare the MFC-ΔSVI% and the percentage change in the cardiac power index (CPI) due to the MFC (MFC-ΔCPI%) with the baseline values of the pulse pressure variation (PPV) and stroke volume variation (SVV) in terms of their abilities to predict fluid responsiveness. Materials and methods: The SVI, CPI, SVV, and PPV were recorded before 100 mL of isotonic saline was infused (MFC), after MFC was completed, and after an additional 400 mL of isotonic saline was infused to complete 500 mL of fluid loading (FL). Patients whose SVI increased more than 15% after the FL were defined as fluid responders. Results: Sixty-seven patients completed the study and 35 (52%) of them were responders.The areas under the receiver operating characteristics curves for the MFC-ΔSVI% and MFC-ΔCPI% (0.94; 95% CI: 0.86-0.99 and 0.89; 95% CI: 0.79-0.95, respectively) were significantly higher than those for the SVV and PPV (0.63; 95% CI: 0.50-0.75 and 0.55; 95% CI: 0.42-0.67, respectively) (p < 0.001 for all of the comparisons). The gray zone analysis revealed that the MFC-ΔSVI% values of 12 patients were in the gray zone. Of the 12, the MFC-ΔCPI% values of 7 patients were outside of the gray zone. Conclusion: Fluid responsiveness can be predicted more accurately using the MFC-ΔSVI% and MFC-ΔCPI% than using the SVV and PPV. Additionally, concomitant use of the MFC-ΔSVI% and MFC-ΔCPI% is recommended, as this approach diminishes the number of patients in the gray zone.

Perioperative myocardial injury after elective neurosurgery: incidence, risk factors, and effects on mortality.

Perioperative myocardial injury is an important reason of mortality and morbidity after neurosurgery. It usually is missed due to its asymptomatic character. In the present study, we investigated myocardial injury after noncardiac surgery (MINS) incidence, the risk factor for MINS, and association of MINS with 30-day mortality in neurosurgery patients. Patients with cardiac risk who underwent elective neurosurgery were enrolled to present prospective cohort study. The patients' demographics, comorbidities, medications used, medical history, and type of operation were recorded. The high-sensitivity cardiac troponin (hs-cTn) levels of the patients were measured 12, 24, and 48 h after surgery. The patients were considered MINS-positive if at least one of their postoperative hs-cTn measurement values was ≥ 14 ng/l. All the patients were followed up for 30 days after surgery for evaluation of their outcomes, including total mortality, mortality due to cardiovascular cause, and major cardiac events. A total of 312 patients completed the study and 64 (20.5%) of them was MINS-positive. Long antiplatelet or anticoagulant drug cessation time (OR: 4.9, 95% CI: 2.1-9.4) was found the most prominent risk factor for MINS occurrence. The total mortality rate was 2.4% and 6.2% in patients MINS-negative and MINS-positive, respectively (p = 0.112). The mortality rate due to cardiovascular reasons (0.8% for without MINS, 4.7 for with MINS, and p = 0.026) and incidence of the major cardiac events (4% for without MINS, 10.9 for with MINS, and p = 0.026) were significantly higher in patients with MINS. MINS is a common problem after neurosurgery, and high postoperative hs-cTn level is associated with mortality and morbidity.

Measuring potassium level in packed red blood cells before using: Word of caution for congenital cardiac surgery.

BACKGROUND AND AIM OF THE STUDY: Transfusion-associated hyperpotassemia is a serious complication of packed red blood cell (PRBC) transfusion after congenital cardiac surgery. Our study aimed to identify risk factors and potential preventive measures of transfusion-associated hyperpotassemia in neonates and infants after congenital cardiac surgery. METHODS: Pediatric patients who underwent congenital cardiac surgery and need transfusion were enrolled in this prospective study. The potassium concentration of PRBC was checked from the sample taken from the segment. The volume of transfusion, age of PRBC, potassium concentration of unit were recorded. The estimated increment of potassium level in patients after PRBC transfusion was calculated. RESULTS: Seventy-four individual patients, 95 distinct transfusions, 112 blood products were evaluated. The mean age of the blood unit was 3.8 ± 1.4 days. The mean potassium concentration in the PRBCs was 9.9 ± 2.4 mmol/L. A weak correlation was observed between the potassium value of the PRBC and the age of PRBC (p = 0.049, r = 0.2, y = 0.24 × x + -0.68). There was a weak correlation between the potassium value of PRBCs and the age of the unit (p < 0.001, r = 0.37, y = 2.8 × x + -3.6). CONCLUSIONS: Before transfusion, even PRBC is fresh, measuring the potassium level of PRBC and the potassium that will be given to the pediatric patient with transfusion can prevent transfusion-related hyperpotassemia and related complications. Otherwise, high potassium levels, which may be overlooked despite being fresh, may cause serious complications, even cardiac arrest, especially in neonates and infants.

Ability of short-time low peep challenge to predict fluid responsiveness in mechanically ventilated patients in the intensive care.

Short-time low PEEP challenge (SLPC, application of additional 5 cmH2O PEEP to patients for 30 s) is a novel functional hemodynamic test presented in the literature. We hypothesized that SLPC could predict fluid responsiveness better than stroke volume variation (SVV) in mechanically ventilated intensive care patients. Heart rate, mean arterial pressure, stroke volume index (SVI) and SVV were recorded before SLPC, during SLPC and before and after 500 mL fluid loading. Patients whose SVI increased more than 15% after the fluid loading were defined as fluid responders. Reciever operating characteristics (ROC) curves were generated to evaluate the abilities of the methods to predict fluid responsiveness. Fifty-five patients completed the study. Twenty-five (46%) of them were responders. Decrease percentage in SVI during SLPC (SVIΔ%-SLPC) was 11.6 ± 5.2% and 4.3 ± 2.2% in responders and non-responders, respectively (p < 0.001). A good correlation was found between SVIΔ%-SLPC and percentage change in SVI after fluid loading (r = 0.728, P < 0.001). Areas under the ROC curves (ROC-AUC) of SVIΔ%-SLPC and SVV were 0.951 (95% CI 0.857-0.991) and 0.747 (95% CI 0.611-0.854), respectively. The ROC-AUC of SVIΔ%-SLPC was significantly higher than that of SVV (p = 0.0045). The best cut-off value of SVIΔ%-SLPC was 7.5% with 90% sensitivity and 96% specificity. The percentage change in SVI during SLPC predicts fluid responsiveness in intensive care patients who are ventilated with low tidal volumes; the sensitivity and specificity values are higher than those of SVV.

Residual neuromuscular block in the postanesthesia care unit: incidence, risk factors, and effect of neuromuscular monitoring and reversal agents.

BACKGROUND: The aim of this study was to determine the incidence of residual neuromuscular block (RNMB) in a tertiary care hospital. Secondary goals were to examine the characteristics of the use of intraoperative neuromuscular monitoring (NMM) and different reversal agents by the attending anesthesiologists, and to determine the factors related to the patient and perioperative processes on the development of RNMB. METHODS: The patients' arrival time at the postanesthesia care unit was accepted as point zero (T0). The acceleromyography of the patients' adductor pollicis muscle was monitored for NMM. Train of four ratios (TOFRs) were recorded at 0, 10, 20, and 30 min. A TOFR < 0.9 was defined as RNMB. Patients' demographic and perioperative data were also recorded. RESULTS: A total of 216 patients completed the study. RNMB was observed in 47 patients (21.8%). Seventy-eight patients (36%) were followed up with NMM. Neostigmine and sugammadex were used in 174 (80.5%) and 42 (19.5%) patients, respectively, and they were both underdosed (21.2 ± 3.0 mcg/kg and 1.5 ± 0.7 mg/kg, respectively). Use of neostigmine and absence of NMM were risk factors for RNMB (p: 0.01 and 0.001, respectively) along with the number of additional doses (>1 doses, p ≤ 0.02) and the timing of the last dose of rocuronium (<88 min, p ≤ 0.01). None of the patients who received both NMM and sugammadex experienced RNMB. DISCUSSION: The RNMB incidence was found to be 21.8%. The main reasons of it were the lack of intraoperative NMM and inappropriate use of reversal agents. Despite strong recommendations, the use of NMM is still insufficient and reversal agents are still underdosed.

Gray-to-white matter ratio predicts long-term recovery potential of patients with aneurysmal subarachnoid hemorrhage.

Predicting recovery potential of patients with aneurysmal subarachnoid hemorrhage (aSAH) is challenging. We investigated whether the gray-to-white matter ratio (GWR) predicts recovery of cognitive function (CF) and quality of life (QOL) of these patients. We analyzed data of 69 patients with aSAH. Patients' demographics, comorbidities, and neurological status were recorded. One year after aSAH, Montreal Cognitive Assessment (MoCA) and Short Form-36 (SF-36) tests were administered to the patients, and brain volumes of patients were examined using MRI. Three years after aSAH, MoCA and SF-36 tests were conducted again. Differences between the test scores 1 and 3 years after aSAH were evaluated (ΔMoCA and ΔSF-36). Patients with ΔMoCA ≥ 4 points and those with ΔSF-36 ≥ 8 points were referred to as good MoCA and SF-36 recovery, respectively. ΔMoCA correlated with GWR in male and female patients (females: p < 0.001, R2 = 0.581; males: p < 0.001, R2 = 0.481). In female patients, GWR > 1.34 predicted good MoCA recovery with 82.3% sensitivity and 80% specificity, and in male patients, GWR > 1.36 predicted good MoCA recovery with 80% sensitivity and 95% specificity. ΔSF-36 correlated with GWR in male and female patients (females: p < 0.001, R2 = 0.479; males: p < 0.001, R2 = 0.627). In female patients, GWR > 1.35 predicted good SF-36 recovery with 74% sensitivity and 84% specificity, and in male patients, GWR > 1.38 predicted good SF-36 recovery with 72% sensitivity and 92% specificity. GWR is a good predictor of the recovery of CF and QOL in patients with aSAH and, thus, can help physicians to better organize rehabilitation of patients.

Transpulmonary thermodilution monitoring-guided hemodynamic management improves cognitive function in patients with aneurysmal subarachnoid hemorrhage: a prospective cohort comparison.

BACKGROUND: The effects of goal-directed hemodynamic management using transpulmonary thermodilution (TPT) monitor on the cognitive function of patients with aneurysmal subarachnoid hemorrhage (aSAH) remain unclear. The present study aimed to determine whether hemodynamic management with TPT monitor provides better cognitive function compared with standard hemodynamic management. METHODS: Patients with aSAH who were admitted to the intensive care unit in 2016 were assigned to cohort 1, and those admitted in 2017 were assigned to cohort 2. In cohort 1, hemodynamic and fluid management was performed in accordance with the traditional pressure-based hemodynamic parameters and clinical examination, whereas in cohort 2, it was performed in accordance with the TPT monitor-measured flow-based parameters. The incidence of delayed cerebral ischemia (DCI) and pulmonary edema (PE) was determined. The functional outcome of patients was assessed using the modified Rankin scale (mRS) score and Montreal cognitive assessment (MoCA) test at 1 year following aSAH. RESULTS: Cohort 1 included 45 patients and cohort 2 included 39 patients who completed the trial. The incidence of DCI (38% versus 26%) and PE (11% versus 3%) was comparable between the cohorts (p > 0.05). The mRS score was similar between the cohorts (p = 0.11). However, the MoCA score was 20.2 (19.2-21.4) and 23.5 (22.2-24.8) in cohort 1 and cohort 2, respectively (p < 0.001). Accordingly, the occurrence of poor MoCA score (38% versus 18%) was significantly lower in cohort 2 (p = 0.045). CONCLUSIONS: TPT monitor-based hemodynamic management provides better cognitive outcome than standard hemodynamic management in patients with aSAH.

Comparison of ability of pulse pressure variation to predict fluid responsiveness in prone and supine position: an observational study.

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 (PPVΔ%) 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, PPVΔ% was ≤ - 20%. All of these patients had CST2 < 31 ml/cmH2O, seven had BMI > 30 kg/m2, and two had IAPT2 > 15 mmHg. In 16 patients, PPVΔ% was ≥ 20%. In these patients, 10 had CST2 < 31 ml/cmH2O, 10 had BMI > 30 kg/m2, and 12 had IAPT2 > 15 mmHg. Thirty-nine patients were volume responder. When all patients were examined for predicting fluid responsiveness, area under curves (AUC) of PPVT2 (0.790, 95%CI 0.690-0.870) was significantly lower than AUC of PPVT1 (0.937, 95%CI 0.878-0.997) with ROC analysis (p = 0.002). When patients whose CST2 was < 31 ml/cmH2O and whose BMI was > 30 kg/m2 were excluded from analysis separately, AUC of PPVT2 became similar to PPVT1. PPV in the prone can predict fluid responsiveness as good as PPV in the supine, only if BMI is < 30 kg/m2 and CS value at prone is > 31 ml/cmH2O.

Relation of gray-white matter ratio with long-term cognitive functions and quality of life in patients with mild to moderate aneurysmal subarachnoid hemorrhage: a prospective observational study.

BACKGROUND: In the present study, we hypothesized that a low gray matter-white matter ratio (GWR) is associated with poor cognitive function and low quality of life in patients with mild to moderate (WFNS ≤3) aneurysmal subarachnoid hemorrhage (aSAH). METHODS: All patients with aSAH who were admitted to the neurointensive care unit (Neuro ICU) and whose WFNS score was ≤ 3 were enrolled in the study. During the Neuro ICU follow-up period, the following variables were recorded: demographics, neurological status, comorbidities, time elapsed between onset of bleeding and Neuro ICU admission, treatment method, number of days with vasospasm symptoms (DVS) and vasopressor usage. One year after bleeding, all patients except those who could not answer the questionnaires appropriately were administered the MoCA and SF-36 tests, and brain magnetic resonance imaging and then volumetric brain analysis were performed. RESULTS: Eighty-two patients completed the study. One year after aSAH, cognitive dysfunction and low quality of life were observed in 59.8% and 25.6% of patients, respectively. Among the variables obtained during Neuro ICU follow-up, DVS was found to be a major risk factor for cognitive dysfunction (OR: 3.9, 95% CI: 1.9-7.8; p < 0.001), poor quality of life (OR: 2.8, 95% CI: 1.4-5.3, p = 0.002) and a lower GWR value (p < 0.001, correlation coefficient = -0.410, R2 = 0.234). One year after aSAH, higher GWR values were associated with higher MoCA (R2 = 0.506 for males, R2 = 0.413 for females) and SF-36 (R2 = 0.270 for males, R2 = 0.364 for females) scores in both genders. Also, GWR ≤ 1.35 in males and GWR ≤1.33 in females indicated MoCApoor patients with over 80% specificity and sensitivity. CONCLUSION: GWR has good correlation with the MoCA and SF-36 score, and a low GWR can indicate cognitive dysfunction. In this context, GWR can be used as an additional method to evaluate cognitive function and quality of life.

Comparison of Column Solid-Phase Extraction Procedures for Spectrophotometric Determination of E129 (Allura Red) in Foodstuff, Pharmaceutical, and Energy Drink Samples.

Two novel spectrophotometric determination procedures based on retention of Allura Red onto Amberlite XAD-1180 and XAD-16 resins for its preconcentration, purification, and separation were developed. Analytical parameters of the methods including pH, eluent type, sample volume, and sample and eluent flow rates, were investigated and optimized. Interference effects of some cations, anions, and widely used food dyes were also investigated. Detection limits of the two methods were found to be 1.2 and 1.5 µg/L for XAD-1180 and XAD-16 columns, respectively, under optimum conditions. Linear calibration curve ranges of the methods were 0.4-8.0 and 0.5-6.0 µg/mL of Allura Red for XAD-1180 and XAD-16 resins, respectively. Preconcentration factors were found as 80 for both the XAD-1180 and XAD-16 columns using maximum sample volume and minimum eluent volume. RSDs of the methods were below 6% throughout all experiments. All absorbance measurements were performed at 506 nm. Validations of the methods were performed comparatively with determination of the Allura Red contents of some foodstuff, pharmaceutical, and energy drink samples. Allura Red concentrations in investigated solid and liquid samples ranged from 298 to 501 µg/g and 53.8 to 508 µg/mL, respectively. Satisfactory results were obtained from the real samples analysis. Allura Red contents of samples were determined to be highly similar using the two extraction methods. Comparisons of the methods were performed by analysis of Allura Red contents of the real samples. In addition to analytical parameters, adsorption isotherm studies were performed for the two kinds of Amberlite resins. It was observed that developed methods fit the linear form of the Freundlich adsorption isotherm model. All of the experimental results suggested that the developed SPE procedures are suitable for separation, preconcentration, and determination of Allura Red in solid and liquid matrixes.

Successful results of early nucleos(t)ide analogue treatment for liver transplantation candidates with severe acute hepatitis B infection.

BACKGROUND: Early treatment of severe acute hepatitis B virus (HBV) infection with nucleos(t)ide analogues may prevent progression to acute liver failure (ALF). PATIENTS AND METHODS: The charts of 24 patients who were treated for severe acute HBV infection (either INR ≥ 1.5 or INR≥ 1.4 and total bilirubin ≥ 20 mg/dL at the referring institution or after admission) between April 2021 and May 2023 (inclusive) were evaluated retrospectively. Twelve patients were women; median [range] age: 48 [35-68]. Entecavir (0.5 mg/day) (n = 16) or tenofovir disoproxil fumarate (245 mg/day) (n =8) were used depending on availability. RESULTS: Two patients required liver transplant which was performed successfully in one (no suitable donor for the other). Deterioration to ALF was prevented in 22 of the 24 cases (92%); these patients could be discharged after median (range) 12 (5-24) days following initiation of the antiviral drug. There was no significant difference in efficacy between the two antiviral agents. The anti-HBsAg antibody became positive in 16 patients (73%); one other patient became HBsAg negative at 1 month after discharge but was lost to follow up. Five patients (23%) are still HBsAg positive but all except one have started treatment in the last 6 months. One of the recently treated 4 patients stopped taking the antiviral drug at his own will and one has become anti-HIV antibody positive during follow up. CONCLUSION: Early treatment of severe acute HBV infection with entecavir or tenofovir disoproxil fumarate prevents the need for liver transplant and consideration of living donors.

Erector spinae plane block as a rescue therapy in following cholecystectomy: a historical cohort study.

OBJECTIVE: The aim of this study is to evaluate the effect of erector spinae plane block (ESPB) as a rescue therapy in the recovery room. MATERIALS AND METHODS: This single-center historical cohort study included patients who received either ESPB or intravenous meperidine for pain management in the recovery room. Patients' numeric rating scale (NRS) scores and opoid consumptions were evaluated. RESULTS: One hundred and eight patients were included in the statistical analysis. Sixty-two (57%) patients received ESPB postoperatively (pESPB) and 46 (43%) patients were managed with IV meperidine boluses only (IV). The cumulative meperidine doses administered were 0 (0-40) and 30 (10-80) mg for the pESPB and IV groups, respectively (p < 0.001). NRS scores of group pESPB were significantly lower than those of Group IV on T30 and T60. CONCLUSION: ESPB reduces the frequency of opioid administration and the amount of opioids administered in the early post-operative period. When post-operative rescue therapy is required, it should be considered before opioids.

OBJETIVO: Evaluar el efecto del bloqueo del plano erector espinal (ESPB) como terapia de rescate en la sala de recuperación. MÉTODO: Este estudio de cohortes histórico de un solo centro incluyó a pacientes que recibieron ESPB o meperidina intravenosa para el tratamiento del dolor en la sala de recuperación. Se evaluaron las puntuaciones de la escala de calificación numérica (NRS) de los pacientes y los consumos de opiáceos. RESULTADOS: En el análisis estadístico se incluyeron 108 pacientes. Recibieron ESPB 62 (57%) pacientes y los otros 46 (43%) fueron manejados solo con bolos de meperidina intravenosa. Las dosis acumuladas de meperidina administradas fueron 0 (0-40) y 30 (10-80) mg para los grupos de ESPB y de meperidina sola, respectivamente (p < 0.001). Las puntuaciones de dolor del grupo ESPB fueron significativamente más bajas que las del grupo de meperidina sola en T30 y T60. CONCLUSIONES: El ESPB reduce la frecuencia de administración de opiáceos y la cantidad de estos administrada en el posoperatorio temprano. Cuando se requiera terapia de rescate posoperatoria, se debe considerar antes que los opiáceos.

Fluid preloading before beach chair positioning for arthroscopic shoulder procedures: a randomized controlled trial.

BACKGROUND AND OBJECTIVES: The Beach Chair Position (BCP) has many advantages such as less neurovascular injury and better intra-articular visualization, but it has also negative consequences, including hemodynamic instability. Although maintaining normal Mean Arterial Pressure (MAP) is important, fluid management is also a crucial concept for hemodynamic stability. The main objective of this study is whether preloading before positioning would be effective for less hemodynamic instability. METHODS: This randomized, controlled study was conducted in a single center in the Istanbul University, Istanbul Faculty of Medicine. Forty-nine patients undergoing elective arthroscopic surgery in the BCP were recruited. In the study group, crystalloid fluid at 10...mL.kg-1 of ideal body weight was administered intravenously 30...min before the BCP for preloading. The primary outcome measures were differences of hemodynamic variables as MAP, Stroke Volume (SV), Heart Rate (HR), and Cardiac Output (CO). The secondary outcome measures were Postoperative Nausea and Vomiting (PONV) rates in postoperative first day, surgical satisfaction scale, total ephedrine dose used during surgery, and total amount of fluid. RESULTS: The MAP, CO, and SV measurements of the study group were higher than those of the control group in the 5th minute after the BCP (respectively, p...=...0.001, p...=...0.016, p...=...0.01). The total amount of crystalloid and surgical satisfaction scales were higher in the study group (respectively, p...=...0.016, p...=...0.001). Total amount of colloid and ephedrine dose used in the intraoperative period, and PONV rates were lower in the study group (p...=...0.003, p...=...0.018, p...=...0.019, respectively). CONCLUSION: Consequently, preloading can be favorable approach to preserve hemodynamic stability.

Simultaneous Preconcentration and Spectrophotometric Determination of Two Colorants (E110 and E133) in Some Foodstuffs Using a New Mussel-Inspired Adsorbent.

BACKGROUND: A naturally occurring material, namely sporopollenin (SP), was subjected to an easy physical surface modification process called a polydopamine coating. The treatment changed the acid-base properties of the surface, so that in the new form the SP surface gained a very attractive character for anionic dyes. OBJECTIVE: The aim of the study was to develop preconcentration and subsequent spectrophotometric determination methods for two anionic colorants, brilliant blue (BB) and sunset yellow (SY), using polydopamine-coated (PDC) SP. METHOD: The experiments were carried out in a column system, and the effects of experimental parameters were studied to determine optimal conditions for the quantitative, simultaneous spectrophotometric determination of the dyes. RESULTS: The dyes could be detected at µg/L levels in their binary mixtures, so the detection limits were found to be 1.5 and 4.3 µg/L in the linear dynamic ranges of 0.0-3.5 and 0-8 µg/mL for BB and SY, respectively. The proposed material and procedure led to quantitative recoveries of between 95 and 100% for the dyes. CONCLUSIONS: The procedure was applied to real food samples containing BB and SY and both dyes were successfully determined in liquid and solid foodstuffs. The mussel-inspired surface modification is proposed as a useful process to modify the surface of SP. HIGHLIGHTS: The mussel-inspired polydopamine dip-coating method was adopted to modify the surface of SP for the first time. The PDCSP was successfully used to create a new adsorptive preconcentration method for simultaneous spectrophotometric determination of BB and SY in foodstuffs.

Comparison of arterial blood pressure and cardiac index-based hemodynamic management on cognitive function in elderly patients undergoing spinal surgery: a randomized clinical trial.

BACKGROUND: Postoperative delayed neurocognitive recovery (DNR) is frequent in elderly patients. Prevention of DNR is essential to achieve a better postoperative outcome. METHODS: The aim of the present study was to compare mean arterial pressure (MAP) and Cardiac Index (CI) based hemodynamic management on early cognitive function in elderly patients undergoing spinal surgery. Sixty patients aged ≥60 years were enrolled. Patients were randomized to one of two groups. In Group MAP, hemodynamic management of patients was performed according to the MAP value. In Group CI, hemodynamic management of patients was performed according to the CI value. In all patients, standard anesthesia method was used and regional cerebral oxygen saturation (rScO2) was measured. Cognitive functions of patients were assessed by Montreal cognitive assessment (MoCA) test before surgery and seven days after surgery. Change in MoCA test (ΔMoCA) was calculated. RESULTS: Postoperative MoCA score was significantly greater in Group CI (25.2±2.4) than Group MAP (23.9±2.5) (P=0.046). The ΔMoCAs were 1 (IQR, 0-3) and 3 (IQR, 2-3.5) in Group CI and MAP respectively (P<0.001). Lowest and average rScO2 values were significantly greater, and the decreased load of rScO2 below the threshold of 10% (AUCΔ10%) and 20% (AUCΔ20%) below its baseline were significantly lower in Group CI (P<0.05). CONCLUSIONS: CI-based hemodynamic management provided better postoperative cognitive function and higher intraoperative rScO2 when compared with MAP-based hemodynamic management.

Simultaneous Spectrophotometric Determination of Brilliant Blue and Tartrazine in Diverse Sample Matrices after Solid Phase Extraction.

BACKGROUND: Brilliant blue (BB) and tartrazine (TZ) are manufactured from petroleum and its products. These are the most popular consumed food dyes and are widely used in foodstuffs. Therefore, overuse of these dyes in foodstuffs and consumption of excessive amounts of these dyes can lead to health problems in humans. OBJECTIVE: The aim of this study was to develop a simple separation and preconcentration method for simultaneous spectrophotometric determination of BB and TZ dyes. METHODS: A column solid-phase separation extraction method combined with UV-Vis spectrophotometry was preferred and developed for single and simultaneous determination of BB and TZ dyes. RESULTS: The preconcentration factor was obtained as 80. Relative standard deviations were below than 4%. Detection limits of the method were determined as 0.29 and 1.21 µg/L for BB and TZ, respectively. Recovery values were obtained between 95-99% and 96-100% for BB and TZ, respectively. 10.9-235.7 µg/g and 1.7-8.0 µg/mL of BB contents of real samples were determined for solid and liquid samples, respectively. TZ concentrations of solid and liquid samples were ranged between 18.7-220.7 µg/g and 5.9-7.5 µg/mL, respectively. CONCLUSIONS: Quantitative extraction results and satisfactory recovery values showed that method was successful and applicable for determination of BB and TZ concentrations in real pharmaceutical, industrial, and foodstuff samples. HIGHLIGHTS: The method has exhibited a high preconcentration factor and effective separation against to matrix ions. The method did not need an experienced operator with high operation experience. Elution solvent can be chosen according to the availability of the chemicals in the laboratory and cheapness of the chemicals.

Surfactant-Assisted Emulsification and Surfactant-Based Dispersive Liquid-Liquid Microextraction Method for Determination of Cu(II) in Food and Water Samples by Flame Atomic Absorption Spectrometry.

Background: Copper (Cu) is an essential metal for humans at certain concentrations. However, it can be toxic at higher concentrations. Therefore, determination of Cu content of foodstuff is important. Objective: The aim of the study was to develop a simple, economical, and environmentally friendly surfactant-mediated extraction method for the determination of Cu using surfactants and flame atomic absorption spectrometry (FAAS). Methods: A nonionic surfactant-assisted emulsification and surfactant-based dispersive liquid-liquid microextraction method was developed for the separation, preconcentration, and determination of Cu by FAAS. Triton X-15 nonionic surfactant, which is insoluble in water, was used as an extractive agent. Triton X-114 (TX-114) nonionic water-soluble surfactant was used as a disperser solvent. Dithizone was used as a complexing agent for complexation of Cu(II) at pH 4. Results: The detection and quantitation limits of the method were determined as 1.61 and 3.82 µg/L, respectively. The preconcentration factor was obtained as 50. Relative SD based on 10 replicates was obtained as 3.7%. Accuracy of the developed method was proved using certified standard reference materials. Cu(II) content of edible mushroom samples was determined between 12 and 19 µg/g. Recoveries were obtained between 96 and 101%. Conclusions: The developed surfactant-assisted emulsification and surfactant-based dispersive liquid-liquid microextraction method has represented the wide linear ranges, low detection limit, and high preconcentration factor for Cu ions. Highlights: TX-114 surfactant was used as both sticking agent and disperser solvent. The method does not require expert personnel and high operational costs. The method is environmentally friendly because mainly surfactants and low-toxicity organic solvents are used in the recommended procedure.

Ability of mini-fluid challenge to predict fluid responsiveness in obese patients undergoing surgery in the prone position.

BACKGROUND: Pulse pressure variation (PPV) and stroke volume variation (SVV) can predict fluid responsiveness effectively. However, high Body Mass Index (BMI) can restrict their use due to changes in respiratory system compliance (CS), intra-abdominal pressure, and stroke volume (SV) in the prone position. Therefore, we aimed to investigate the effectiveness of mini-fluid challenge (MFC) in predicting fluid responsiveness in obese (BMI ≥30 kg/m2) patients in the prone position. METHODS: A total of 33 patients undergoing neurosurgery were included. After standardized anesthesia induction, patients' PPV, SVV, stroke volume index (SVI) and CS values were recorded in the prone position (T1), after the infusion of 100 mL of crystalloid named as MFC (T2) and after fluid loading was completed with additional 400 mL of crystalloid. Patients whose SVI increased more than 15% after the fluid loading were defined as volume responders. RESULTS: Fifteen (45%) patients were responders to 500 mL fluid loading. After the 100 mL fluid load, a higher percentage increase in SVI was observed among responders (P<0.001), with values of 6.6% (6.2-8.6%) and 3.5% (1.7-4.8%) in responders and non-responders, respectively. Areas under the receiver operating characteristic curves of MFC, PPV, and SVV were 0.967 (95% CI: 0.838-0.999), 0.683 (95% CI: 0.499-0.834), and 0.709 (95% CI: 0.526-0.853), respectively. The area under the curve of MFC was significantly higher than that of PPV (P=0.003) and SVV (P=0.005). CONCLUSIONS: The increase in SVI after a rapid infusion of 100 mL crystalloid could predict fluid responsiveness in patients with BMI ≥30 kg/m2 in the prone position.

A challenge with 5 cmH2O of positive end-expiratory pressure predicts fluid responsiveness in neurosurgery patients with protective ventilation: an observational study.

BACKGROUND: Positive end-expiratory pressure (PEEP) increment induces a decrease in Stroke Volume Index (SVI). We hypothesized that the magnitude of SVI reduction due to a 5 cmH2O increase in PEEP could predict fluid responsiveness during low tidal volume ventilation. METHODS: Forty-eight patients completed the study. Heart rate, mean arterial pressure, SVI, pulse pressure variation (PPV) and stroke volume variation (SVV) were recorded before short-time low PEEP (SLPC) challenge (applied additional 5 cmH2O PEEP to patients for 30 seconds), during SLPC and before and after 500 mL fluid loading. Patients whose SVI increased more than 15% after the fluid loading were defined as volume responders. RESULTS: Twenty-one (44%) patients were volume responder. Decrease percentage in SVI during SLPC was 17.4±3.6% and 9.9±3.1% in responders and non-responders respectively (P<0.001). A strong correlation was found between decrease percentage in SVI during SLPC and increase percentage in SVI after fluid loading (R2=0.680, P<0.001). The area under receiver operating curves generated to predict fluid responsiveness for decrease percentage in SVI during SLPC (0.944, 95% CI: 0.836-0.990) was significantly higher than that for PPV (0.777, 95% CI: 0.634-0.884, P=0.025) and SVV (0.773, 95% CI: 0.630-0.882, P=0.022). Best cut-off values of decrease percentage in SVI during SLPC was -14.2 with 95% sensitivity and 89% specificity. CONCLUSIONS: SVI change percentage during SLPC can predict fluid responsiveness better than PPV and SVV in neurosurgery patients ventilated with low tidal volume.

Simultaneous Preconcentration and Determination of Brilliant Blue and Sunset Yellow in Foodstuffs by Solid-Phase Extraction Combined UV-Vis Spectrophotometry.

Background: Brilliant Blue and Sunset Yellow, two highly water-soluble synthetic food dyes, are the most popular food dyes used and consumed. Although they are not highly toxic, some health problems can be observed when excessive amounts of food products containing these dyes are consumed. Objectives: The aim of the study was to develop a simultaneous UV-Vis combined solid-phase extraction method, based on the adsorption onto Amberlite XAD-8 resin, for determination of Brilliant Blue and Sunset Yellow dyes. Methods: Sample solution was poured into the reservoir of the column and permitted to gravitationally pass through the column at 2 mL/min flow rate. Adsorbed dyes were eluted to 5 mL of final volume with 1 mol/L HNO3 in ethanol solution by applying a 2 mL/min flow rate. Dye concentrations of the solution were determined at 483 and 630 nm for Sunset Yellow and Brilliant Blue, respectively. Results: The detection limits of the method for Brilliant Blue and Sunset Yellow were determined as 0.13 and 0.66 ng/mL, respectively. Preconcentration factor was 80. Brilliant Blue contents of real food samples were found to be between 11 and 240 µg/g. Sunset Yellow concentrations of foodstuffs were determined to be between 19 and 331 µg/g. Conclusions: Economical, effective, and simple simultaneous determination of Brilliant Blue and Sunset Yellow was achieved by using a solid-phase extraction combined UV-Vis spectrometry method. Highlights: The method is applicable and suitable for routine analysis in quality control laboratories without the need for expert personnel and high operational costs because the instrumentation is simple and inexpensive.