The respiratory rate (RR) is considered one of the most informative vital signals. A well-validated standard for RR measurement in mechanically ventilated patient is capnography; a noninvasive ...technique for expiratory CO2 measurements. Reliable RR measurements in spontaneously breathing patients remains a challenge as continuous mainstream capnography measurements are not available. This study aimed to assess the accuracy of RR measurement using electrical impedance tomography (EIT) in healthy volunteers and intensive care unit (ICU) patients on mechanical ventilation and spontaneously breathing post-extubation. Comparator methods included RR derived from both capnography and bioimpedance electrocardiogram (ECG) measurements. Approach: Twenty healthy volunteers wore an EIT belt and ECG electrodes while breathing through a capnometer within a 10 - 40 breaths per minute (BPM) range. Nineteen ICU patients underwent similar measurements during pressure support ventilation and spontaneously breathing after extubation from mechanical ventilation. Stable periods with regular breathing and no artefacts were selected, and agreement between measurement methods was assessed using Bland-Altman analysis for repeated measurements. Main Result: Bland-Altman analysis revealed a bias less than 0.2 BPM, with tight limits of agreement (LOA) 1.5 BPM in healthy volunteers and ventilated ICU patients when comparing EIT to capnography. Spontaneously breathing ICU patients had wider LOA (2.5 BPM) when comparing EIT to ECG bioimpedance, but gold standard comparison was unavailable. RR measurements were stable for 91% of the time for capnography, 68% for EIT, and 64% of the ECG bioimpedance signals. After extubation, the percentage of stable periods decreased to 48% for EIT signals and to 55% for ECG bioimpedance. Significance: In periods of stable breathing, EIT demonstrated excellent RR measurement accuracy in healthy volunteers and ICU patients. However, stability of both EIT and ECG bioimpedance RR measurements declined in spontaneously breathing patients to approximately 50% of the time. 
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Prolonged weaning from mechanical ventilation is associated with poor clinical outcome. Therefore, choosing the right moment for weaning and extubation is essential. Electrical Impedance Tomography ...(EIT) is a promising innovative lung monitoring technique, but its role in supporting weaning decisions is yet uncertain. We aimed to evaluate physiological trends during a T-piece spontaneous breathing trail (SBT) as measured with EIT and the relation between EIT parameters and SBT success or failure.
This is an observational study in which twenty-four adult patients receiving mechanical ventilation performed an SBT. EIT monitoring was performed around the SBT. Multiple EIT parameters including the end-expiratory lung impedance (EELI), delta Tidal Impedance (ΔZ), Global Inhomogeneity index (GI), Rapid Shallow Breathing Index (RSBI
), Respiratory Rate (RR
) and Minute Ventilation (MV
) were computed on a breath-by-breath basis from stable tidal breathing periods.
EELI values dropped after the start of the SBT (p < 0.001) and did not recover to baseline after restarting mechanical ventilation. The ΔZ dropped (p < 0.001) but restored to baseline within seconds after restarting mechanical ventilation. Five patients failed the SBT, the GI (p = 0.01) and transcutaneous CO
(p < 0.001) values significantly increased during the SBT in patients who failed the SBT compared to patients with a successful SBT.
EIT has the potential to assess changes in ventilation distribution and quantify the inhomogeneity of the lungs during the SBT. High lung inhomogeneity was found during SBT failure. Insight into physiological trends for the individual patient can be obtained with EIT during weaning from mechanical ventilation, but its role in predicting weaning failure requires further study.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Supplemental oxygen therapy is a mainstay of modern neonatal intensive care for preterm infants. However, both insufficient and excess oxygen delivery are associated with adverse outcomes. Automated ...or closed loop FiO2 control has been developed to keep SpO2 within a predefined target range more effectively.
The aim of this study was to investigate the feasibility of closed loop FiO2 control by Predictive Intelligent Control of Oxygenation (PRICO) on the Fabian ventilator in maintaining SpO2 within a target range (88/89-95%) in preterm infants on different modes of invasive and noninvasive respiratory support. In two tertiary neonatal intensive care units, preterm infants with an FiO2 >0.21 were included and received an 8 h nonblinded treatment period of closed loop FiO2 control by PRICO, flanked by two 8 h control periods of routine manual control (RMC1 and RMC2).
32 preterm infants were included (median gestational age 26 + 5 weeks IQR 25 + 5-27 + 6, median birthweight 828 grams IQR 704-930). Six patients received invasive respiratory support, while 26 received noninvasive respiratory support (18 CPAP, 4 DuoPAP, and 4 nasal IMV). The time percentage within the SpO2 target range was increased with PRICO (74.4% IQR 67.8-78.5) compared to RMC1 (65.8% IQR 51.1-77.8; p = 0.011) and RMC2 (60.6% IQR 56.2-66.6; p < 0.001) with an estimated median difference of 6.0% (95% CI 1.2-11.5) and 9.8% (95% CI 6.0-13.0), respectively.
In preterm infants on invasive and noninvasive respiratory supports, closed loop FiO2 control by PRICO compared to RMC is feasible and superior in maintaining SpO2 within target ranges.
Background: Preterm neonates are extensively monitored to require strict oxygen target attainment for optimal outcomes. In daily practice, detailed oxygenation data are hardly used and crucial ...patterns may be missed due to the snapshot presentations and subjective observations. This study aimed to develop a web-based dashboard with both detailed and summarized oxygenation data in real-time and to test its feasibility to support clinical decision making. Methods: Data from pulse oximeters and ventilators were synchronized and stored to enable real-time and retrospective trend visualizations in a web-based viewer. The dashboard was designed based on interviews with clinicians. A preliminary version was evaluated during daily clinical rounds. The routine evaluation of the respiratory condition of neonates (gestational age < 32 weeks) with respiratory support at the NICU was compared to an assessment with the assistance of the dashboard. Results: The web-based dashboard included data on the oxygen saturation (SpO
2
), fraction of inspired oxygen (FiO
2
), SpO
2
/FiO
2
ratio, and area < 80% and > 95% SpO
2
curve during time intervals that could be varied. The distribution of SpO
2
values was visualized as histograms. In 65% of the patient evaluations (
n
= 86) the level of hypoxia was assessed differently with the use of the dashboard. In 75% of the patients the dashboard was judged to provide added value for the clinicians in supporting clinical decisions. Conclusions: A web-based customized oxygenation dashboard for preterm neonates at the NICU was developed and found feasible during evaluation. More clear and objective information was found supportive for clinicians during the daily rounds in tailoring treatment strategies.
Transition immediately after birth is a complex physiological process. The neonate has to establish sufficient ventilation to ensure significant changes from intra-uterine to extra-uterine ...circulation. If hypoxia or bradycardia or both occur, as commonly happens during immediate transition in preterm neonates, cerebral hypoxia-ischemia may cause perinatal brain injury. The primary objective of the COSGOD phase III trial is to investigate whether it is possible to increase survival without cerebral injury in preterm neonates of less than 32 weeks of gestation by targeting cerebral tissue oxygen saturation (crSO
) using specified clinical treatment guidelines during the immediate transition period after birth (the first 15 min) in addition to the routine monitoring of arterial oxygen saturation (SpO
) and heart rate (HR).
COSGOD III is an investigator-initiated, randomized, multi-center, multi-national, phase III clinical trial. Inclusion criteria are neonates of less than 32 weeks of gestation, decision to provide full life support, and parental informed consent. Exclusion criteria are severe congenital malformations of brain, heart, lung, or prenatal cerebral injury or a combination of these. The premature infants will be randomly assigned to study or control groups. Both groups will have a near-infrared spectroscopy (NIRS) device (left frontal), pulse oximeter (right palm/wrist), and electrocardiogram placed immediately after birth. In the study group, the crSO
, SpO
, and HR readings are visible, and the infant will receive treatment in accordance with defined treatment guidelines. In the control group, only SpO
and HR will be visible, and the infant will receive routine treatment. The intervention period will last for the first 15 min after birth during the immediate transition period and resuscitation. Thereafter, each neonate will be followed up for primary outcome to term date or discharge. The primary outcome is mortality or cerebral injury (or both) defined as any intra-ventricular bleeding or cystic periventricular leukomalacia (or both). Secondary outcomes are neonatal morbidities.
crSO
monitoring during immediate transition has been proven to be feasible and improve cerebral oxygenation during immediate transition. The additional monitoring of crSO
with dedicated interventions may improve outcome of preterm neonates as evidenced by increased survival without cerebral injury.
ClinicalTrials.gov Identifier: NCT03166722 . Registered March 5, 2017.
Fragile X syndrome is caused by expansion and subsequent methylation of a CGG trinucleotide repeat in the FMR1 5′-untranslated region. Southern blot analysis is typically required to determine ...expansion size for triplet repeat lengths >200. We describe a triplet-primed polymerase chain reaction-based method using automated capillary electrophoresis detection for qualitative assessment of expanded CGG repeats.
The assay uses triplet-primed polymerase chain reaction in combination with GC-melting reagents and substitution of 7-deaza-2-deoxyGTP for dGTP. Amplicons are resolved by capillary electrophoresis.
A distinctive pattern of tapering or “stutter” polymerase chain reaction amplification was evident on capillary electrophoresis in male and female patients harboring all expanded allele lengths examined (up to 2000 CGG repeats) and could be used to differentiate normal, intermediate, premutation, and full mutation alleles. Full mutation alleles exhibited an additional late-migrating amplicon on capillary electrophoresis. Mixing experiments demonstrated sensitivity as low as 1% for detection of the full mutation allele. In a 1275-sample concordance study against our existing polymerase chain reaction platform (with Southern blot analysis for repeat lengths ≥55), the triplet-primed polymerase chain reaction method exhibited 100% concordance for normal, intermediate, expanded, and full mutation alleles. This method also detected the full mutation alleles in DNA isolated from blood spots.
This assay provides an accurate assessment of FMR1 repeat status and holds promise for use in carrier and newborn screening. The method distinguishes normal homozygous females from full mutation carrying females. Although the method is not useful for accurate sizing, it supplements the classic polymerase chain reaction method and results in significant reduction in the number of Southern blot analyses required to be performed in the laboratory to accurately assess the FMR1 genotype in all individuals.
Introduction: Evaluation of pharmacotherapy during intensive care treatment is commonly based on subjective, intermittent interpretations of physiological parameters. Real-time visualization and ...analysis may improve drug effect evaluation. We aimed to evaluate the effects of the respiratory stimulant doxapram objectively in preterm infants using continuous physiological parameters. Methods: In this longitudinal observational study, preterm infants who received doxapram therapy were eligible for inclusion. Physiological data (1 Hz) were used to assess respiration and to evaluate therapy effects. The oxygen saturation (SpO 2 )/fraction of inspired oxygen (FiO 2 ) ratio and the area under the 89% SpO 2 curve (duration × saturation depth below target) were calculated as measures of hypoxemia. Regression analyses were performed in 1-h timeframes to discriminate therapy failure (intubation or death) from success (no intubation). Results: Monitor data of 61 patients with a median postmenstrual age (PMA) at doxapram initiation of 28.7 (IQR 27.6–30.0) weeks were available. The success rate of doxapram therapy was 56%. Doxapram pharmacodynamics were reflected in an increased SpO 2 and SpO 2 /FiO 2 ratio as well as a decrease in episodes with saturations below target (SpO 2 <89%). The SpO 2 /FiO 2 ratio, corrected for PMA and mechanical ventilation before therapy start, discriminated best between therapy failure and success (highest AUC ROC of 0.83). Conclusion: The use of continuous physiological monitor data enables objective and detailed interpretation of doxapram in preterm infants. The SpO 2 /FiO 2 ratio is the best predictive parameter for therapy failure or success. Further implementation of real-time data analysis and treatment algorithms would provide new opportunities to treat newborns.
Non-invasive monitoring of cerebral tissue oxygen saturation (rcSO
) during transition is of growing interest. Different near-infrared spectroscopy (NIRS) techniques have been developed to measure ...rcSO
. We compared rcSO
values during the immediate transition in preterm neonates measured with frequency-domain NIRS (FD-NIRS) with those measured with continuous-wave NIRS (CW-NIRS) devices in prospective observational studies.
We compared rcSO
values measured with an FD-NIRS device during the first 15 min after birth in neonates with a gestational age ≥ 30 weeks but < 37 weeks born at the Erasmus MC- Sophia Children's Hospital, Rotterdam, the Netherlands, with similar values measured with a CW-NIRS device in neonates born at the Medical University of Graz, Austria. Mixed models were used to adjust for repeated rcSO
measurements, with fixed effects for time (non-linear), device, respiratory support and the interaction of device and respiratory support with time. Additionally, parameters such as total haemoglobin concentration and oxygenated and deoxygenated haemoglobin concentrations measured by FD-NIRS were analysed.
Thirty-eight FD-NIRS measurements were compared with 58 CW-NIRS measurements. The FD-NIRS rcSO
values were consistently higher than the CW-NIRS rcSO
values in the first 12 min, irrespective of respiratory support. After adjustment for respiratory support, the time-dependent trend in rcSO
differed significantly between techniques (p < 0.01).
As cerebral saturation measured with the FD-NIRS device differed significantly from that measured with the CW-NIRS device, differences in absolute values need to be interpreted with care. Although FD-NIRS devices have technical advantages over CW-NIRS devices, FD-NIRS devices may overestimate true cerebral oxygenation and their benefits might not outweigh the usability of the more clinically viable CW-NIRS devices.
Background: Heart rate (HR) detection in premature infants using electrocardiography (ECG) is challenging due to a low signal amplitude and the fragility of the premature skin. Recently, the dynamic ...light scattering (DLS) technique has been miniaturized, allowing noninvasive HR measurements with a single sensor. Objective: The aim was to determine the accuracy of DLS for HR measurement in infants, compared to ECG-derived HR. Methods: Stable infants with a gestational age of ≥26 weeks, monitored with ECG, were eligible for inclusion. HR was measured with the DLS sensor at 5 different sites for 15 min each. We recorded every 10th second of the DLS-derived HR and the DLS signal-to-noise ratio (SNR), and the ECG-derived HR was extracted for analysis. Patients were randomly divided into 2 groups. In the first group, the optimal SNR cut-off value was determined and then applied to the second group to assess agreement. Results: HR measurements from 31 infants were analyzed. ECG-DLS paired data points were collected at the forehead, an upper extremity, the thorax, a lower extremity, and the abdomen. When applying the international accuracy standard for HR detection, DLS accuracy in the first group (n = 15) was optimal at the forehead (SNR cut-off 1.66). Application of this cut-off to the second group (n = 16) showed good agreement between DLS-derived HR and ECG-derived HR (bias –0.73 bpm; 95% limits of agreement –15.46 and 14.00 bpm) at the forehead with approximately 80% (i.e., 1,066/1,310) of all data pairs remaining. Conclusion: The investigated DLS sensor was sensitive to movement, overall providing less accurate HR measurements than ECG and pulse oximetry. In this study population, specific measurement sites provided excellent signal quality and good agreement with ECG-derived HR.
Three isostructural compounds of the formula {M(bipy)(H2O)(H2P2O7)2·2H2O} bipy = 2,2′-bipyridine; M = Ni (1), Co (2), Mn (3) have been isolated from aqueous solutions containing the corresponding ...metal(II) chloride hydrate with a bipy and sodium pyrophosphate solution in a 1:1:2 molar ratio, and their structures were determined by single-crystal X-ray diffraction. The structures of 1–3 consist of neutral aqua(2,2′-bipyridine)metal(II) dinuclear units bridged by two dihydrogenpyrophosphate groups adopting a bidentate/monodentate mode. Each metal ion in 1–3 is six-coordinate in a distorted octahedral geometry, with the reduced value of the angle subtended by the chelating bipy at the metal ion 79.6(1)° (1), 77.32(7)° (2), and 72.9(1)° (3) being the main source of this distortion. The values of the intramolecular metal–metal separation are 5.271(1) Å (1), 5.3065(8) Å (2), and 5.371(1) Å (3). Magnetic susceptibility measurements on polycrystalline samples of 1–3 in the temperature range 1.9–300 K shows weak intramolecular ferromagnetic J = +1.86(2) cm–1 (1) and +0.25(1) cm–1 (2) and antiferromagnetic J = −0.48(1) cm–1 (3) coupling, with the spin Hamiltonian being defined as H = −JS M1· S M1a. This rarely observed coordination mode for dihydrogenpyrophosphate leads to ferromagnetic coupling in complexes of nickel(II) or cobalt(II).
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