Impact of frailty, biomarkers and basic biochemical parameters on outcomes of comatose patients in status epilepticus: a single-center prospective pilot study.

BACKGROUND: Status epilepticus (SE) is a severe acute condition in neurocritical care with high mortality. Searching for risk factors affecting the prognosis in SE remains a significant issue. The primary study's aim was to test the predictive values of the Clinical Frailty Scale (CFS) and the Modified 11-item Frailty Index (mFI-11), the biomarkers and basic biochemical parameters collected at ICU on the Glasgow Outcome Scale (GOS) assessed at hospital discharge (hosp), and three months later (3 M), in comatose patients with SE. The secondary aim was to focus on the association between the patient's state at admission and the duration of mechanical ventilation, the ICU, and hospital stay. METHODS: In two years single-centre prospective pilot study enrolling 30 adult neurocritical care patients with SE classified as Convulsive SE, A.1 category according to the International League Against Epilepsy (ILAE) Task Force without an-/hypoxic encephalopathy, we evaluated predictive powers of CFS, mFI-11, admission Status Epilepticus Severity Score (STESS), serum protein S100, serum Troponin T and basic biochemical parameters on prognosticating GOS using univariate linear regression, logistic regression and Receiver Operating Characteristic (ROC) analysis. RESULTS: Our study included 60% males, with a mean age of 57 ± 16 years (44-68) and a mean BMI of 27 ± 5.6. We found CFS, mFI-11, STESS, and age statistically associated with GOS at hospital discharge and three months later. Among the biomarkers, serum troponin T level affected GOS hosp (p = 0.027). Serum C-reactive protein significance in prognosticating GOS was found by logistic regression (hosp p = 0.008; 3 M p = 0.004), and serum calcium by linear regression (hosp p = 0.028; 3 M p = 0.015). In relation to secondary outcomes, we found associations between the length of hospital stay and each of the following: age (p = 0.03), STESS (p = 0.009), and serum troponin T (p = 0.029) parameters. CONCLUSIONS: This pilot study found promising predictive powers of two frailty scores, namely CFS and mFI-11, which were comparable to age and STESS predictors regarding the GOS at hospital discharge and three months later in ICU patients with SE. Among biomarkers and biochemical parameters, only serum troponin T level affected GOS at hospital discharge.

Yoga Breathing (Maheshwarananda's Modified Bhujangini Pranayama): A Randomized Study in Hypobaric Hypoxemia at 3,650 m Elevation.

Hypobaric hypoxemia represents a risk factor for body integrity and challenges its homeostasis. We examined whether practicing Maheshwarananda's modified bhujangini pranayama yoga breathing technique would influence hypobaric hypoxemia at an altitude of 3,650 m. An international randomized two-period, two-sequence crossover intervention study was conducted in September 2019 in the Himalayas. We compared 5-minute testing periods of pranayama breathing with normal resting breathing in 20 subjects divided randomly into two groups of 10 individuals; all had a daily practice of Maheshwarananda's modified bhujangini pranayama and were nonsmokers, lacto vegetarians, and alcohol abstainers. We measured the arterial saturation by pulse oximetry (SpO2; our primary outcome variable), end-tidal carbon dioxide partial pressure (EtCO2), respiratory rate, and heart rate at two altitudes: (1) 378 m (T0); and (2) 3,650 m (T1 = 2nd day, T2 = 4th day at the camp) immediately after finishing each testing period. We also monitored the presence of acute mountain sickness using the Lake Louise Scoring System. Mean SpO2 at 3,650 m increased right after the yoga breathing exercise from 88.60% to 90.35% at T1, and from 88.35% to 90.60% at T2 (T1 p = 0.007, T2 p = 0.004). No significant changes were observed in heart rate or EtCO2. The mean rate of normal control resting breathing was 13/min; the mean rate was 7/min during the yoga breathing. Right after Maheshwarananda's modified bhujangini pranayama hypobaric hypoxemia decreased as measured by SpO2, whereas EtCO2 and heart rate stayed comparable with the control resting breathing.

Corrigendum: Real-time effects of lateral positioning on regional ventilation and perfusion in an experimental model of acute respiratory distress syndrome.

[This corrects the article DOI: 10.3389/fphys.2023.1113568.].

Real-time effects of lateral positioning on regional ventilation and perfusion in an experimental model of acute respiratory distress syndrome.

Low-volume lung injury encompasses local concentration of stresses in the vicinity of collapsed regions in heterogeneously ventilated lungs. We aimed to study the effects on ventilation and perfusion distributions of a sequential lateral positioning (30°) strategy using electrical impedance tomography imaging in a porcine experimental model of early acute respiratory distress syndrome (ARDS). We hypothesized that such strategy, including a real-time individualization of positive end-expiratory pressure (PEEP) whenever in lateral positioning, would provide attenuation of collapse in the dependent lung regions. A two-hit injury acute respiratory distress syndrome experimental model was established by lung lavages followed by injurious mechanical ventilation. Then, all animals were studied in five body positions in a sequential order, 15 min each: Supine 1; Lateral Left; Supine 2; Lateral Right; Supine 3. The following functional images were analyzed by electrical impedance tomography: ventilation distributions and regional lung volumes, and perfusion distributions. The induction of the acute respiratory distress syndrome model resulted in a marked fall in oxygenation along with low regional ventilation and compliance of the dorsal half of the lung (gravitational-dependent in supine position). Both the regional ventilation and compliance of the dorsal half of the lung greatly increased along of the sequential lateral positioning strategy, and maximally at its end. In addition, a corresponding improvement of oxygenation occurred. In conclusion, our sequential lateral positioning strategy, with sufficient positive end-expiratory pressure to prevent collapse of the dependent lung units during lateral positioning, provided a relevant diminution of collapse in the dorsal lung in a porcine experimental model of early acute respiratory distress syndrome.

Comparison of nursing students' performance of cardiopulmonary resuscitation between 1 semester and 3 semesters of manikin simulations in the Czech Republic: a non-randomized controlled study

PURPOSE: This study aimed to assess the effect of simulation teaching in critical care courses in a nursing study program on the quality of chest compressions of cardiopulmonary resuscitation (CPR). METHODS: An observational cross-sectional study was conducted at the Faculty of Health Studies at the Technical University of Liberec. The success rate of CPR was tested in exams comparing 2 groups of students, totaling 66 different individuals, who completed half a year (group 1: intermediate exam with model simulation) or 1.5 years (group 2: final theoretical critical care exam with model simulation) of undergraduate nursing critical care education taught completely with a Laerdal SimMan 3G simulator. The quality of CPR was evaluated according to 4 components: compression depth, compression rate, time of correct frequency, and time of correct chest release. RESULTS: Compression depth was significantly higher in group 2 than in group 1 (P=0.016). There were no significant differences in the compression rate (P=0.210), time of correct frequency (P=0.586), or time of correct chest release (P=0.514). CONCLUSION: Nursing students who completed the final critical care exam showed an improvement in compression depth during CPR after 2 additional semesters of critical care teaching compared to those who completed the intermediate exam. The above results indicate that regularly scheduled CPR training is necessary during critical care education for nursing students.

Incidence of surgical site infections after cervical spine surgery: results of a single-center cohort study adhering to multimodal preventive wound control protocol.

PURPOSE: The incidence of surgical site infections is considered a relevant indicator of perioperative and postoperative care quality. The aim of this study is to analyze and evaluate SSIs after elective cervical spine surgery under the guidance of our preventive multimodal wound protocol. METHODS: A monocentric observational cohort study analyzed 797 patients who underwent cervical spine surgery from 2005 to 2010 (mean age 51.58 ± 11.74 year, male 56.09%, mean BMI 26.87 ± 4.41, ASA score 1-2 in 81.68% of patients), fulfilling the entry criteria: (1) cervical spine surgery performed by neurosurgeons (degenerative disease 85.19%, trauma 11.04%, tumor 3.76%), (2) elective surgery, (3) postoperative care in our neurointensive care unit. Our preventive wound control protocol management focused mainly on antibiotic prophylaxis, wound hygiene regime, and drainage equipment. All wound complications and surgical site infections were monitored up for 1 year after surgery. RESULTS: We had only 2 (0.25%) patients with SSI after cervical spine surgery-one organ/space infection (osteomyelitis, primary due to liquorrhea) after anterior surgical approach, and one deep surgical site infection (due to dehiscence) after posterior approach. We had 17 (2.13%) patients with some wound complications (secretion 7, dehiscence 4, hematoma 1, edema 3, and liquorrhea 2) that were not classified as SSI according to the CDC guidelines. CONCLUSION: Concerning our study population of patients undergoing elective cervical surgery, with ASA scores 1-2 in 81.68% of our patients, the incidence of SSI was 0.14% after anterior surgical approach, 1.4% after posterior surgical approach, and 0.25% altogether in the referred cohort.

Prone positioning may increase lung overdistension in COVID-19-induced ARDS.

Real-time effects of changing body position and positive end-expiratory pressure (PEEP) on regional lung overdistension and collapse in individual patients remain largely unknown and not timely monitored. The aim of this study was to individualize PEEP in supine and prone body positions seeking to reduce lung collapse and overdistension in mechanically ventilated patients with coronavirus disease (COVID-19)-induced acute respiratory distress syndrome (ARDS). We hypothesized that prone positioning with bedside titrated PEEP would provide attenuation of both overdistension and collapse. In this prospective observational study, patients with COVID-19-induced ARDS under mechanical ventilation were included. We used electrical impedance tomography (EIT) with decremental PEEP titration algorithm (PEEPEIT-titration), which provides information on regional lung overdistension and collapse, along with global respiratory system compliance, to individualize PEEP and body position. PEEPEIT-titration in supine position followed by PEEPEIT-titration in prone position were performed. Immediately before each PEEPEIT-titration, the same lung recruitment maneuver was performed: 2 min of PEEP 24 cmH2O and driving pressure of 15 cmH2O. Forty-two PEEPEIT-titration were performed in ten patients (21 pairs supine and prone positions). We have found larger % of overdistension along the PEEP titration in prone than supine position (P = 0.042). A larger % of collapse along the PEEP titration was found in supine than prone position (P = 0.037). A smaller respiratory system compliance was found in prone than supine position (P < 0.0005). In patients with COVID-19-induced ARDS, prone body position, when compared with supine body position, decreased lung collapse at low PEEP levels, but increased lung overdistension at PEEP levels greater than 10 cm H2O.Trial registration number: NCT04460859.

Individualized perioperative management in transoral spine surgery: a single-center cohort study evaluating surgical wound complications and wound infections.

BACKGROUND: Transoral spine surgery is specific due to both its surgical approach and the spectrum of diseases it targets. Patients with high age and elevated clinical frailty scores are often involved, and there are reports of increased risks of surgical site infection (SSI) due to extended exposures requiring maxilotomy or mandibulotomy. Our case series describes surgical wound complications under the meticulous application of individualized perioperative multimodal management. METHODS: Our primary outcome was the occurrence of SSI and the secondary outcome was the occurrence of other noninfectious wound complications evaluated in 22 adult patients who consecutively underwent the transoral spine surgery from 2001 to 2018 (trauma - C2, cervical nonunion: 6 patients, 27%; tumor: 4 patients, 18%; osteomyelitis: 6 patients, 27%; other non-traumatic cases: 6 patients, 27%). Structuralized data comprising parameters related to nosocomial infections after spine surgery were continuously processed and put into specialized database of preventive multimodal nosocomial infection control protocol that was used as a main source of analyzed parameters. The mean age of studied cohort was 54.9 [Formula: see text] 15.5 years, with 68% males, mean body mass index (BMI) 24.9 [Formula: see text] 5.22, and the mean clinical frailty score was 2.59 [Formula: see text] 1.07. There were 7 patients (32%) who only had the transoral approach and 15 patients (68%) having this approach followed by additional posterior approach. We observed SSI from all wound complications for up to one year after surgery. RESULTS: There were 4 (18%) superficial wound complications from transoral approach, but none of them were infected. We had 2 patients (13%) with deep wound infections after subsequent posterior approach, but only one (4.5%) was classified as SSI. CONCLUSIONS: We describe the wound complications and the incidence of SSI in a series of 22 patients after the transoral surgery. Considering the average values of the clinical frailty score reaching 2.59, American Society of Anesthesiologists score of 2.73, and the BMI of 26.87, the transoral spine surgery did not seem to be a considerable risk for SSI in the analyzed cohort, provided preventive perioperative multimodal management is properly individualized and followed.

Atrial Septostomy for Left Ventricular Unloading During Extracorporeal Membrane Oxygenation for Cardiogenic Shock: Animal Model.

OBJECTIVES: The aim of this study was to quantify and understand the unloading effect of percutaneous balloon atrial septostomy (BAS) in acute cardiogenic shock (CS) treated with venoarterial (VA) extracorporeal membranous oxygenation (ECMO). BACKGROUND: In CS treated with VA ECMO, increased left ventricular (LV) afterload is observed that commonly interferes with myocardial recovery or even promotes further LV deterioration. Several techniques for LV unloading exist, but the optimal strategy and the actual extent of such procedures have not been fully disclosed. METHODS: In a porcine model (n = 11; weight 56 kg [53-58 kg]), CS was induced by coronary artery balloon occlusion (57 minutes [53-64 minutes]). Then, a step-up VA ECMO protocol (40-80 mL/kg/min) was run before and after percutaneous BAS was performed. LV pressure-volume loops and multiple hemoglobin saturation data were evaluated. The Wilcoxon rank sum test was used to assess individual variable differences. RESULTS: Immediately after BAS while on VA ECMO support, LV work decreased significantly: pressure-volume area, end-diastolic pressure, and stroke volume to ∼78% and end-systolic pressure to ∼86%, while superior vena cava and tissue oximetry did not change. During elevating VA ECMO support (40-80 mL/kg/min) with BAS vs without BAS, we observed 1) significantly less mechanical work increase (122% vs 172%); 2) no end-diastolic volume increase (100% vs 111%); and 3) a considerable increase in end-systolic pressure (134% vs 144%). CONCLUSIONS: In acute CS supported by VA ECMO, atrial septostomy is an effective LV unloading tool. LV pressure is a key component of LV work load, so whenever LV work reduction is a priority, arterial pressure should carefully be titrated low while maintaining organ perfusion.

Yogic breathing in hypobaric environment: breathing exercising and its effect on hypobaric hypoxemia and heart rate at 3,650-m elevation.

High altitude sojourn is a risk factor for hypobaric hypoxemia and subsequent altitude sickness. The aim of this study was to analyze the effect of new type of yogic breathing-Maheshwarananda's new Modified Bhujangini Pranayama performed by active yoga practitioners-on the arterial haemoglobin saturation of oxygen (measured by the pulse oximetry - SpO2) and the heart rate compared to normal spontaneous resting breathing. A pilot prospective study was conducted in the Himalayas at an altitude of 3,650 m. We monitored SpO2 and pulse rate in 34 experienced yoga practitioners. Within the 3 measurement days at the altitude of 3,650 m, the mean value of SpO2 increased from 89.11± 4.78 to 93.26±4.44 (P<0.001) after the yogic breathing exercise. No significant changes were observed in pulse rate (P<0.230) measured before and after yogic breathing. The new Yogic breathing-Maheshwarananda's Modified Bhujangini Pranayama-is increasing the arterial haemoglobin saturation compared to normal resting spontaneous breathing. The heart rate was not affected by this type of yogic breathing.

Targeted lateral positioning decreases lung collapse and overdistension in COVID-19-associated ARDS.

BACKGROUND: Among the challenges for personalizing the management of mechanically ventilated patients with coronavirus disease (COVID-19)-associated acute respiratory distress syndrome (ARDS) are the effects of different positive end-expiratory pressure (PEEP) levels and body positions in regional lung mechanics. Right-left lung aeration asymmetry and poorly recruitable lungs with increased recruitability with alternating body position between supine and prone have been reported. However, real-time effects of changing body position and PEEP on regional overdistension and collapse, in individual patients, remain largely unknown and not timely monitored. The aim of this study was to individualize PEEP and body positioning in order to reduce the mechanisms of ventilator-induced lung injury: collapse and overdistension. METHODS: We here report a series of five consecutive mechanically ventilated patients with COVID-19-associated ARDS in which sixteen decremental PEEP titrations were performed in the first days of mechanical ventilation (8 titration pairs: supine position immediately followed by 30° targeted lateral position). The choice of lateral tilt was based on X-Ray. This targeted lateral position strategy was defined by selecting the less aerated lung to be positioned up and the more aerated lung to be positioned down. For each PEEP level, global and regional collapse and overdistension maps and percentages were measured by electrical impedance tomography. Additionally, we present the incidence of lateral asymmetry in a cohort of forty-four patients. RESULTS: The targeted lateral position strategy resulted in significantly smaller amounts of overdistension and collapse when compared with the supine one: less collapse along the PEEP titration was found within the left lung in targeted lateral (P = 0.014); and less overdistension along the PEEP titration was found within the right lung in targeted lateral (P = 0.005). Regarding collapse within the right lung and overdistension within the left lung: no differences were found for position. In the cohort of forty-four patients, ventilation inequality of > 65/35% was observed in 15% of cases. CONCLUSIONS: Targeted lateral positioning with bedside personalized PEEP provided a selective attenuation of overdistension and collapse in mechanically ventilated patients with COVID-19-associated ARDS and right-left lung aeration/ventilation asymmetry. TRIAL REGISTRATION: Trial registration number: NCT04460859.

The effect of neural noise on spike time precision in a detailed CA3 neuron model.

Experimental and computational studies emphasize the role of the millisecond precision of neuronal spike times as an important coding mechanism for transmitting and representing information in the central nervous system. We investigate the spike time precision of a multicompartmental pyramidal neuron model of the CA3 region of the hippocampus under the influence of various sources of neuronal noise. We describe differences in the contribution to noise originating from voltage-gated ion channels, synaptic vesicle release, and vesicle quantal size. We analyze the effect of interspike intervals and the voltage course preceding the firing of spikes on the spike-timing jitter. The main finding of this study is the ranking of different noise sources according to their contribution to spike time precision. The most influential is synaptic vesicle release noise, causing the spike jitter to vary from 1 ms to 7 ms of a mean value 2.5 ms. Of second importance was the noise incurred by vesicle quantal size variation causing the spike time jitter to vary from 0.03 ms to 0.6 ms. Least influential was the voltage-gated channel noise generating spike jitter from 0.02 ms to 0.15 ms.

Pattern storage in a sparsely coded neural network with cyclic activation.

We investigate an artificial neural network model with a modified Hebb rule. It is an auto-associative neural network similar to the Hopfield model and to the Willshaw model. It has properties of both of these models. Another property is that the patterns are sparsely coded and are stored in cycles of synchronous neural activities. The cycles of activity for some ranges of parameter increase the capacity of the model. We discuss basic properties of the model and some of the implementation issues, namely optimizing of the algorithms. We describe the modification of the Hebb learning rule, the learning algorithm, the generation of patterns, decomposition of patterns into cycles and pattern recall.