Comparison Between Volume Controlled Ventilation And Pressure Controlled Ventilation In Morbidly Obese Patients Undergoing Laparoscopic Gastric sleeve Surgery

Background Although numerous studies conducted in the past years, there is no superior guideline that indicates the best ventilation mode during laparoscopic anesthesia inobese patients. There are numerous studies with dissimilar controversial points. The management of oxygenation in a morbid obese patient undergoing laparoscopic procedures presents many challenging aspects to the anesthetist. Objective The aim of this study was to equate the effect of pressure controlled ventilation (PCV) vs. volume controlled ventilation (VCV) on respiratory, oxygenation parameters and post operative complications. Patients and Methods This study was conducted on 80 patients who underwent laparoscopic gastric sleeve surgery in Ain Shams University Hospitals. Post induction of Anesthesia, Patients were divided into two groups. The first group mechanical ventilation setting was volume controlled ventilation and the second group mechanical ventilation setting was pressure controlled ventilation. Results The results of our study shows that despite some valuable effects regarding plateau and mean airway pressure with PCV, there is no momentous clinical difference between volume controlled ventilation (VCV) and pressure controlled ventilation (PCV) in obese patients undergoing laparoscopic gastric sleeve surgery. However, pressure controlled ventilation shows slightly more favorable results regarding post extubation oxygen saturation and the decrease of post operative basal atelectasis. It appears that using dual modes would be an epitome approach with lower complications and similar outcomes.

Individualized PEEP titration guided by intratidal compliance profile analysis improves regional ventilation – a randomized controlled trial

Background Application of positive end-expiratory pressure (PEEP) improves lung aeration and reduces mechanical stress during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy to titrate optimal PEEP. By analyzing the intratidal compliance profiles, PEEP may be titrated patient-individually. Methods After obtaining informed consent, we measured respiratory system mechanics, regional ventilation in 60 consecutive patients undergoing elective surgery, randomly allocated to the control group (PEEP = 5 cmH2O) or the intervention group receiving individually titrated PEEP, guided by intratidal compliance profile analysis. Primary endpoint was the frequencies of nonlinear intratidal compliance (CRS) profiles of the respiratory system (horizontal, increasing, decreasing and mixed). We further investigated respiratory and hemodynamic variables and regional ventilation. Results Frequencies of CRS profiles were comparable between the groups. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH2O, p<0.001] respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. The loss of ventral and dorsal regional ventilation was higher in the control [ventral: 41.0 (16.3) %, dorsal: 25.9 (13.9) %] than in the intervention group [ventral: 29.3 (17.6) %, dorsal: 16.4 (12.7) %, p (ventral) = 0.039, p (dorsal) = 0.028]. Conclusions Individualized PEEP titration according to bedside compliance profile analysis improves regional ventilation without affecting respiratory and hemodynamic variables negatively and may be a promising approach to patient-individual ventilation setting.

Individualized PEEP titration guided by intratidal compliance profile analysis improves regional ventilation – a randomized controlled trial

Background Application of positive end-expiratory pressure (PEEP) improves lung aeration and reduces mechanical stress during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy to titrate optimal PEEP. By analyzing the intratidal compliance profiles, PEEP may be titrated patient-individually. Methods After obtaining informed consent, we measured respiratory system mechanics and regional ventilation in 60 consecutive patients undergoing elective surgery, randomly allocated to the control group (PEEP = 5 cmH 2 O) or the intervention group receiving individually titrated PEEP, guided by intratidal compliance profile analysis. Primary endpoint was the nonlinear intratidal compliance. We further investigated respiratory and hemodynamic variables, regional ventilation and compliance profiles. Results Compliance was comparable between control [63.2 (14.0) mL·cmH 2 O -1 ] and intervention group [67.8 (15.9) mL·cmH 2 O -1 , p = 0.271]. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH 2 O] respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. Relative thoracic electrical impedance was better maintained in the intervention group (89.3 (19.4) %) than in the control group (78.3 (23.6) %, p < 0.001). No significant differences in dorsal to ventral ventilation distribution was found between the two groups. Conclusions Individualized PEEP titration according to bedside compliance profile analysis improves regional ventilation without affecting respiratory and hemodynamic variables negatively and may be a promising approach to patient-individual ventilation setting.

Transthoracic Impedance Measured with Defibrillator Pads—New Interpretations of Signal Change Induced by Ventilations

Compressions during the insufflation phase of ventilations may cause severe pulmonary injury during cardiopulmonary resuscitation (CPR). Transthoracic impedance (TTI) could be used to evaluate how chest compressions are aligned with ventilations if the insufflation phase could be identified in the TTI waveform without chest compression artifacts. Therefore, the aim of this study was to determine whether and how the insufflation phase could be precisely identified during TTI. We synchronously measured TTI and airway pressure (Paw) in 21 consenting anaesthetised patients, TTI through the defibrillator pads and Paw by connecting the monitor-defibrillator’s pressure-line to the endotracheal tube filter. Volume control mode with seventeen different settings were used (5–10 ventilations/setting): Six volumes (150–800 mL) with 12 min−1 frequency, four frequencies (10, 12, 22 and 30 min−1) with 400 mL volume, and seven inspiratory times (0.5–3.5 s ) with 400 mL/10 min−1 volume/frequency. Median time differences (quartile range) between timing of expiration onset in the Paw-line (PawEO) and the TTI peak and TTI maximum downslope were measured. TTI peak and PawEO time difference was 579 (432–723) m s for 12 min−1, independent of volume, with a negative relation to frequency, and it increased linearly with inspiratory time (slope 0.47, R 2 = 0.72). PawEO and TTI maximum downslope time difference was between −69 and 84 m s for any ventilation setting (time aligned). It was independent ( R 2 < 0.01) of volume, frequency and inspiratory time, with global median values of −47 (−153–65) m s , −40 (−168–68) m s and 20 (−93–128) m s , for varying volume, frequency and inspiratory time, respectively. The TTI peak is not aligned with the start of exhalation, but the TTI maximum downslope is. This knowledge could help with identifying the ideal ventilation pattern during CPR.

oXirisNet Registry: A Prospective, National Registry on the oXiris Membrane

Worldwide, the widespread use of extracorporeal blood purification therapies (EBPTs) is progressively increasing in everyday clinical practice, particularly in critical care settings. The efficacy of EBPTs on removal of inflammatory mediators is already well established in the literature. Nonetheless, clinical research is particularly cumbersome in this setting, and many clinical trials aiming at exploring the effect of EBPTs on outcomes have failed in demonstrating consistent results regarding 28-day- or hospital-mortality rates. In recent years, data emerging from large registries have been increasingly used to provide real-world evidence on the effectiveness, quality, and safety of EBPTs. The philosophy behind this Italian Registry is a renewal of the concept of “clinical research” in the field of EBPTs applied to critically ill, septic patients with or without acute kidney injury. The platform used for the registry – specifically designed for research purposes and fed by clinical data prospectively observed – promotes good practice with a positive and active interaction with the physician/researcher. This interaction has favorable real-time effects for the specific patient, providing “bed-side clinical feedbacks,” similarly to the decision support system. Examples of these issues are bundles reminders, suggestions for drug adjustment according to the extracorporeal clearance, clinical calculator for body mass index, or mechanical ventilation setting. The platform-physician interaction has additional useful effects on the single utilizing center, providing “mid-term, center-specific clinical feedbacks.” These generally consist of clusters of data taken over a certain period, for example, regarding patients’ outcome, microbiological data, or use of disposable for EBPTs.

Abstract 233: Prehospital End-Tidal CO2 Measurement in Non-Intubated Traumatic Brain Injury Patients: Concordance Between EMS Provider Documentation and Non-Invasive Monitor Data Tracking

Background: End-Tidal CO2 (ETCO2) monitoring is valuable in the management of traumatic brain injury (TBI). In intubated patients it helps prevent hyper/over-ventilation. In non-intubated patients, placing a sensor in the nares allows accurate monitoring of respiratory rate and has other promising uses (e.g. monitoring ETCO2 trends in worsening TBI, COPD, etc). Study Objective: To identify how accurately EMS providers document ETCO2, we compared the values recorded in EMS patient care records (PCR) to monitor data in non-intubated TBI patients. Methods: Cases from 6 EMS agencies reporting continuous monitor data (Philips MRx) in the EPIC Study (NIH 1R01NS071049) were evaluated (4/13-3/17). All ETCO2 data available for this post-hoc review were displayed and accessible to the EMS providers during care. Concordance was defined in two ways (for both highest and lowest ETCO2): ≤5 and ≤3 mmHg difference between the monitor data and PCR-documented values. Results: 106 cases were included [median age: 47 (range: 9-91), 66% male]. The figure shows concordance between PCR documentation and monitor data for both the lowest and highest recorded ETCO2 values. Conclusion: The highest PCR-recorded vs monitor ETCO2 values had excellent concordance for a difference ≤5 mmHg (85.9%) and it was good (76.4%) even when defined at the limits of instrument precision (≤3 for ETCO2 compared to actual pCO2). However, for lowest ETCO2, concordance was very poor (only 42.5% for ≤5). The failure to accurately document low ETCO2 in a “passive-ventilation” setting may also have significant implications for improving ventilatory care among intubated patients because identifying and correcting hypocapnia/hyperventilation in actively-ventilated cases is extraordinarily important. The low concordance rates may be due to the emphasis on discreet, intermittent vital sign documentation rather than ongoing identification and documentation of significant ETCO2 variation.

In-Cabin Vehicle Carbon Monoxide Concentrations under Different Ventilation Settings

This paper explores the impact of choice of ventilation setting (“window open”, “new (external) air” and “recirculate”) on in-vehicle carbon monoxide exposures for commuters travelling by car at different times of the day (morning, midday, and evening) and different seasons (warm and cool) in Auckland, New Zealand. Three near-identical vehicles travelled in close proximity to each other on the same three “loops” out and into the city three times a day, each with a different ventilation setting. Concentrations of carbon monoxide were recorded using portable monitors placed inside each of the vehicles. The season was not found to be a significant factor. However, mean concentrations varied across ventilation settings by the time of day, typically peaking during the morning commute. The mean concentrations were significantly different between ventilation settings, with the recirculate setting found to result in a higher in-vehicle concentration than either new air or windows open but also heavily dependent on the initial in-vehicle concentration. However, this setting was the most effective at avoiding concentration spikes, especially when idling at intersections; an isolated peak event reaching 170 ppm was observed with the “new air” setting when following immediately behind an old, poorly-tuned, and visibly-emitting vehicle. This study suggests that having the windows open is the best setting for maintaining low in-cabin air pollution levels but that recirculate should be used in anticipation of congested conditions.

Quantification of Alveolar Recruitment for the Optimization of Mechanical Ventilation Using Quasi-Static Pressure Volume Curve

Quasi-static, pulmonary pressure-volume (P-V) curves over an inflation-deflation cycle are analyzed using a respiratory system model (RSM), which had been developed for quantitative characterization of the mechanical behavior of the total respiratory system. Optimum mechanical ventilation setting of Positive End Expiratory Pressure (PEEP) for total alveolar recruitment is quantified based on the existing P-V curves of healthy and injured animal models. Our analytical predictions may contribute to the optimization of mechanical ventilation settings for the Acute Respiratory Distress Syndrome (ARDS) patients.