Prediction of Loss of Position during Dynamic Positioning Drilling Operations Using Binary Logistic Regression Modeling

The prediction of loss of position in the offshore industry would allow optimization of dynamic positioning drilling operations, reducing the number and severity of potential accidents. In this paper, the probability of an excursion is determined by developing binary logistic regression models based on a database of 42 incidents which took place between 2011 and 2015. For each case, variables describing the configuration of the dynamic positioning system, weather conditions, and water depth are considered. We demonstrate that loss of position is significantly more likely to occur when there is a higher usage of generators, and the drilling takes place in shallower waters along with adverse weather conditions; this model has very good results when applied to the sample. The same method is then applied for obtaining a binary regression model for incidents not attributable to human error, showing that it is a function of the percentage of generators in use, wind force, and wave height. Applying these results to the risk management of drilling operations may help focus our attention on the factors that most strongly affect loss of position, thereby improving safety during these operations

Determining the likelihood of incidents caused by human error during dynamic positioning drilling operations

[EN] The probability of a human-caused incident occurring during dynamic positioning (DP) drilling operations is determined in this paper using binary logistic regression models built with data on 42 incidents that took place during the period 2011–2015. For each case, a range of variables characterising the configuration of the DP system, weather conditions and water depth are taken into account. These variables are taken into account to develop a logistic regression model that shows the likelihood of an incident being caused by human error. The results obtained show that human-based incidents are significantly more likely to occur when there is a lower usage of thrusters. These results are useful for focusing our attention on variables that may be associated with incidents attributable to human error, as well as for setting operational limits that could help to prevent these incidents and improve safety during these operations.This research received no specific grant from any funding agency, commercial or not-for-profit sectors

Surfactant Nebulization Therapy During NIPPV Ventilation in Surfactant-Deficient Newborn Piglets

Background In recent years, nasal intermittent positive pressure ventilation (NIPPV) has been growing in popularity as a form of noninvasive ventilation for respiratory support in the initial treatment of neonates with surfactant (SF) deficiency. The combination of this type of ventilation with noninvasive SF administration (by nebulization) is an attractive treatment option for respiratory distress syndrome (RDS)-associated pathophysiology of the neonatal lungs. In this study, we aimed to test the tolerability and efficacy of SF nebulization during NIPPV for the treatment of neonatal RDS. Methods Spontaneously-breathing newborn piglets (n = 6/group) with bronchoalveolar lavage (BAL)-induced RDS were assigned to receive during NIPPV (180 min): poractant alfa (400 mg/kg) via an investigational customized vibrating-membrane nebulizer (eFlow-Neos) or poractant alfa (200 mg/kg) as a bolus using the Insure method or no surfactant (controls). Measurement and results We assessed pulmonary, hemodynamic and cerebral effects and performed histological analysis of lung and brain tissue. After repeated BAL, newborn piglets developed severe RDS (FiO2: 1, pH  70 mmHg, PaO2< 70 mmHg, Cdyn < 0.5 ml/cmH2O/kg). In both SF-treated groups, we observed rapid improvement in pulmonary status and also similar hemodynamic, cerebral behavior, and lung and brain injury scores. Conclusion Our results in newborn piglets with severe BAL-induced RDS show the administration of nebulized poractant alfa using the eFlow-Neos nebulizer during NIPPV to be well tolerated and efficacious, suggesting that this noninvasive SF administration option should be explored further.Drs. Rey-Santano, Mielgo, and Gomez-Solaetxe's institutions received funding from Chiesi Farmaceutici and Carlos III Health Institute (PI18/00166) (co-funded by ERDF/ESF, "Investing in your future") and GIU19/026 (University of the Basque Country Research Group

Structural and haemodynamic evaluation of less invasive surfactant administration during nasal intermittent positive pressure ventilation in surfactant-deficient newborn piglets

The most recent approaches to the initial treatment of respiratory distress syndrome (RDS)- involve non-invasive ventilation (NIV) and less-invasive surfactant (SF) administration (LISA). Combining these techniques has been proven a useful treatment option for SF-defi- cient neonates. The objective of this study was to explore the impact on the brain (using cerebral near infrared spectroscopy, NIRS) of different LISA methods during NIV, using nasal intermittent positive pressure ventilation (NIPPV) for treating neonatal RDS. For this, we used five groups of spontaneously breathing newborn piglets (n = 6/group) with bronch- oalveolar lavage (BAL)-induced respiratory distress which received NIPPV only (controls), poractant-alfa using the INSURE-like method (bolus delivery) followed by NIPPV, or porac- tant-alfa using one of three LISA devices, 1) a nasogastric tube (NT), 2) a vascular catheter (VC) or 3) the LISAcath® catheter. We assessed pulmonary, hemodynamic and cerebral effects, and performed histological analysis of lung and brain tissue. Following BALs, the piglets developed severe RDS (pH70 mmHg, PaO2<70 mmHg, dynamic com- pliance<0.5 ml/cmH2O/kg at FiO2 = 1). Poractant-alfa administration using different LISA techniques during NIPPV was well tolerated and efficacious in newborn piglets. In our study, although all groups showed normal physiological ranges of total lung injury score and bio- chemical lung analysis, VC and LISAcath® catheters were associated with better values of lung compliance and lower values of lung damage than NIPPV, NT or INSURE-like meth- ods. Moreover, neither of the SF administration methods used (LISA or INSURE-like) had a significant impact on the histological neonatal brain injury score. Of note, the LISAcath® has been recently withdrawn from the market.Drs. Rey-Santano, Mielgo, and Gomez- Solaetxe’s institutions received funding from Chiesi Farmaceutici (Number 10391902) and the Carlos III Health Institute (PI18/00166) (co-financed by the European Regional Development Fund “A way to make Europe”) and GIU19/026 (University of the Basque Country Research Group). Fabrizio Salomone and Francesca Ricci disclose that they are Chiesi employees. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Aerosol Delivery by Inhalation Catheter and Trachea Digitalization

Neonatal respiratory distress syndrome (RDS) is related with high mortality and morbidity in preterm infants and the best approach to treat it is an open research field. The use of perfluorocarbons (PFC) together with non-invasive respiratory support techniques, such as nasal continuous positive airway pressure (CPAP), has confirmed its effectiveness to achieve a more homogeneous surfactant distribution. The goal of the current study was to evaluate the main features of the aerosol generated by an intracorporeal inhalation catheter, which consists of one central lumen delivering the liquid and six peripheral lumens delivering compressed air. Firstly, experiments were made through an Aerodynamic Particle Sizer (APS) with sterile water and perfluorocarbon FC75 with a driving pressure of 4 bar to analyze properties linked with lung deposition such as the aerodynamic diameter (Da), mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD). Subsequently, a numerical model was developed with CFD techniques. The experimental validation of the numerical model provides an accurate prediction of the air flow axial velocity.This work has been supported by Consolidated Groups from the Basque Government. Technical and human support provided by IZO-SGI, SGIker is gratefully acknowledged

Aerosol Delivery by Inhalation Catheter and Trachea Digitalization

Neonatal respiratory distress syndrome (RDS) is related with high mortality and morbidity in preterm infants and the best approach to treat it is an open research field. The use of perfluorocarbons (PFC) together with non-invasive respiratory support techniques, such as nasal continuous positive airway pressure (CPAP), has confirmed its effectiveness to achieve a more homogeneous surfactant distribution. The goal of the current study was to evaluate the main features of the aerosol generated by an intracorporeal inhalation catheter, which consists of one central lumen delivering the liquid and six peripheral lumens delivering compressed air. Firstly, experiments were made through an Aerodynamic Particle Sizer (APS) with sterile water and perfluorocarbon FC75 with a driving pressure of 4 bar to analyze properties linked with lung deposition such as the aerodynamic diameter (Da), mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD). Subsequently, a numerical model was developed with CFD techniques. The experimental validation of the numerical model provides an accurate prediction of the air flow axial velocity.This work has been supported by Consolidated Groups from the Basque Government. Technical and human support provided by IZO-SGI, SGIker is gratefully acknowledged

Experimental Evaluation of Perfluorocarbon Aerosol Generation with Two Novel Nebulizer Prototypes

The potential of non-invasive ventilation procedures and new minimally invasive techniques has resulted in the research of alternative approaches as the aerosolization for the treatment of respiratory distress syndrome (RDS). The aim of this work was to design two nebulizer prototypes and to evaluate them studying the particle size distribution of the inhaled droplets generated with distilled water and two perfluorocarbons (PFCs). Different experiments were performed with driving pressures of 1⁻3 bar for each compound. An Aerodynamic Particle Sizer was used to measure the aerodynamic diameter (Da), the mass median aerodynamic diameter (MMAD) and the geometric standard deviation (GSD). The results showed that both prototypes produced heterodisperse aerosols with Da mean values in all cases below 5 m. The initial experiments with distilled water showed MMAD values lower than 9 m and up to 15 m with prototype 1 and prototype 2, respectively. Regarding the PFCs, relatively uniform MMAD values close to 12 m were achieved. The air delivery with outer lumens of prototype 1 presented more suitable mass distribution for the generation and delivery of a uniform aerosol than the two half-circular ring geometry proposed in the prototype 2.Funding: This work has been supported by Consolidated Groups from the Basque Government and Fundation VITAL Fundazioa

Experimental and Numerical Modeling of Aerosol Delivery for Preterm Infants

Respiratory distress syndrome (RDS) represents one of the major causes of mortality among preterm infants, and the best approach to treat it is an open research issue. The use of perfluorocarbons (PFC) along with non-invasive respiratory support techniques has proven the usefulness of PFC as a complementary substance to achieve a more homogeneous surfactant distribution. The aim of this work was to study the inhaled particles generated by means of an intracorporeal inhalation catheter, evaluating the size and mass distribution of different PFC aerosols. In this article, we discuss different experiments with the PFC perfluorodecalin (PFD) and FC75 with a driving pressure of 4-5 bar, evaluating properties such as the aerodynamic diameter (Da), since its value is directly linked to particle deposition in the lung. Furthermore, we develop a numerical model with computational fluid dynamics (CFD) techniques. The computational results showed an accurate prediction of the airflow axial velocity at different downstream positions when compared with the data gathered from the real experiments. The numerical validation of the cumulative mass distribution for PFD particles also confirmed a closer match with the experimental data measured at the optimal distance of 60 mm from the catheter tip. In the case of FC75, the cumulative mass fraction for particles above 10 mu m was considerable higher with a driving pressure of 5 bar. These numerical models could be a helpful tool to assist parametric studies of new non-invasive devices for the treatment of RDS in preterm infants.Consolidated Groups from the Basque Government supported this work. Technical and human support provided by IZO-SGI, SGIker (UPV/EHU) is gratefully acknowledged

Aerosol Delivery by Inhalation Catheter and Trachea Digitalization

Neonatal respiratory distress syndrome (RDS) is related with high mortality and morbidity in preterm infants and the best approach to treat it is an open research field. The use of perfluorocarbons (PFC) together with non-invasive respiratory support techniques, such as nasal continuous positive airway pressure (CPAP), has confirmed its effectiveness to achieve a more homogeneous surfactant distribution. The goal of the current study was to evaluate the main features of the aerosol generated by an intracorporeal inhalation catheter, which consists of one central lumen delivering the liquid and six peripheral lumens delivering compressed air. Firstly, experiments were made through an Aerodynamic Particle Sizer (APS) with sterile water and perfluorocarbon FC75 with a driving pressure of 4 bar to analyze properties linked with lung deposition such as the aerodynamic diameter (Da), mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD). Subsequently, a numerical model was developed with CFD techniques. The experimental validation of the numerical model provides an accurate prediction of the air flow axial velocity.This work has been supported by Consolidated Groups from the Basque Government. Technical and human support provided by IZO-SGI, SGIker is gratefully acknowledged