A pilot study of improvised CPAP (iCPAP) via face mask for the treatment of adult respiratory distress in low-resource settings

BACKGROUND: Continuous positive airway pressure (CPAP) is a mode of non-invasive ventilation used to treat a variety of respiratory conditions in the emergency department and intensive care unit. In low-resource settings where ventilators are not available, the ability to improvise a CPAP system from locally available equipment would provide a previously unavailable means of respiratory support for patients in respiratory distress. This manuscript details the design of such a system and its performance in healthy volunteers. METHODS: An improvised CPAP system was assembled from standard emergency department equipment and tested in 10 healthy volunteers (6 male, 4 female; ages 29-33). The system utilizes a water seal and high-flow air to create airway pressure; it was set to provide a pressure of 5 cmH2O for the purposes of this pilot study. Subjects used the system in a monitored setting for 30 min. Airway pressure, heart rate, oxygen saturation, and end-tidal CO2 were monitored. Comfort with the device was assessed via questionnaire. RESULTS: The system maintained positive airway pressure for the full trial period in all subjects, with a mean expiratory pressure (EP) of 5.1 cmH2O (SD 0.7) and mean inspiratory pressure (IP) of 3.2 cmH2O (SD 0.8). There was a small decrease in average EP (5.28 vs 4.88 cmH2O, p = 0.03) and a trend toward decreasing IP (3.26 vs 3.07 cmH2O, p = 0.22) during the trial. No significant change in heart rate, O2 saturation, respiratory rate, or end-tidal CO2 was observed. The system was well tolerated, ranked an average of 4.0 on a 1-5 scale for comfort (with 5 = very comfortable). CONCLUSIONS: This improvised CPAP system maintained positive airway pressure for 30 min in healthy volunteers. Use did not cause tachycardia, hypoxia, or hypoventilation and was well tolerated. This system may be a useful adjunctive treatment for respiratory distress in low-resource settings. Further research should test this system in settings where other positive pressure modalities are not available

Novel Airway Training Tool that Simulates Vomiting: Suction-Assisted Laryngoscopy Assisted Decontamination (SALAD) System

We present a novel airway simulation tool that recreates the dynamic challenges associated with emergency airways. The Suction-Assisted Laryngoscopy Assisted Decontamination (SALAD) simulation system trains providers to use suction to manage emesis and bleeding complicating intubation. We modified a standard difficult-airway mannequin head (Nasco, Ft. Atkinson, WI) with hardwarestore equipment to enable simulation of vomiting or hemorrhage during intubation. A pre- and post-survey was used to assess the effectiveness of the SALAD simulator. We used a 1-5 Likert scale to assess confidence in managing the airway of a vomiting patient and comfort with suction techniques before and after the training exercise. Forty learners participated in the simulation, including emergency physicians, anesthesiologists, paramedics, respiratory therapists, and registered nurses. The average Likert score of confidence in managing the airway of a vomiting or hemorrhaging patient pre-session was 3.10±0.49, and post-session 4.13±0.22. The average score of self-perceived skill with suction techniques in the airway scenario presession was 3.30±0.43, and post-session 4.03±0.26. The average score for usefulness of the session was 4.68±0.15, and the score for realism of the simulator was 4.65±0.17. A training session with the SALAD simulator improved trainee’s confidence in managing the airway of a vomiting or hemorrhaging patient. The SALAD simulation system recreates the dynamic challenges associated with emergency airways and holds promise as an airway training tool. [West J Emerg Med. 2017;18(1)117-120.

Novel Airway Training Tool that Simulates Vomiting: Suction-Assisted Laryngoscopy Assisted Decontamination (SALAD) System

Objective: We present a novel airway simulation tool which recreates the dynamic challenges associated with emergency airways. The Suction-Assisted Laryngoscopy Assisted Decontamination (SALAD) simulation system trains providers to use suction to manage emesis and bleeding complicating intubation. Methods: A standard difficult airway mannequin head (Nasco, Ft. Atkinson, WI) was modified with hardware store equipment to enable simulation of vomiting or hemorrhage during intubation. A pre- and post-survey was used to assess the effectiveness of the SALAD simulator. A 1-5 Likert scale was utilized to assess confidence in managing the airway of a vomiting patient and comfort with suction techniques before and after the training exercise. Results: Forty learners participated in the simulation, including emergency physicians, anesthesiologists, paramedics, respiratory therapists, and registered nurses. The average Likert score of confidence in managing the airway of a vomiting or hemorrhaging patient pre-session was 3.10±0.49, and post-session 4.13±0.22 (p<0.00001).  The average score of self-perceived skill with suction techniques in the airway scenario pre-session was 3.30±0.43, and post-session 4.03±0.26 (p<0.0005). The average score for usefulness of the session was 4.68±0.15, and the score for realism of the simulator was 4.65±0.17.  Conclusion: A training session with the SALAD simulator improved trainee’s confidence in managing the airway of a vomiting or hemorrhaging patient.  We feel the SALAD simulation system recreates the dynamic challenges associated with emergency airways and has the potential to transform airway training

Helicopter-based in-water resuscitation with chest compressions: a pilot study

BACKGROUND: Drowning is a relevant worldwide cause of severe disability and death. The delay of ventilations and chest compressions is a crucial problem in drowning victims. Hence, a novel helicopter-based ALS rescue concept with in-water ventilation and chest compressions was evaluated. METHODS: Cardio pulmonary resuscitation (CPR) and vascular access were performed in a self-inflating Heliboat platform in an indoor wave pool using the Fastrach intubating laryngeal mask, the Oxylator resuscitator, Lund University Cardiopulmonary Assist System (LUCAS) chest compression device and EZ-IO intraosseous power drill. The time requirement and physical exertion on a Visual Analogue Scale (VAS) were compared between a procedure without waves and with moderate swell. RESULTS: Measurement of the elapsed time of the various stages of the procedure did not reveal significant differences between calm water and swell: Ventilation was initiated after 02:48 versus 03:02 and chest compression after 04:20 versus 04:18 min; the intraosseous cannulisation was completed after 05:59 versus 06:30 min after a simulated jump off the helicopter. The attachment of the LUCAS to the mannequin and the intraosseous cannulisation was rated significantly more demanding on the VAS during swell conditions. CONCLUSIONS: CPR appears to be possible when performed in a rescue platform with special equipment. The novel helicopter-based strategy appears to enable the rescuers to initiate CPR in an appropriate length of time and with an acceptable amount of physical exertion for the divers. The time for the helicopter to reach the patient will have to be very short to minimise neurological damage in the drowning victim

Mechanical ventilation and resuscitation under water: Exploring one of the last undiscovered environments - A pilot study

INTRODUCTION: Airway management, mechanical ventilation and resuscitation can be performed almost everywhere - even in space - but not under water. The present study assessed the technical feasibility of resuscitation under water in a manikin model. METHODS: Tracheal intubation was assessed in a hyperbaric chamber filled with water at 20m of depth using the Pentax AWS S100 video laryngoscope, the Fastrach™ intubating laryngeal mask and the Clarus optical stylet with guidance by a laryngeal mask airway (LMA) and without guidance. A closed suction system was used to remove water from the airways. A test lung was ventilated to a maximum depth of 50m with a modified Oxylator(®) EMX resuscitator with its expiratory port connected either to a demand valve or a diving regulator. Automated chest compressions were performed to a maximum depth of 50m using the air-driven LUCAS™ 1. RESULTS: The mean cumulative time span for airway management until the activation of the ventilator was 36s for the Fastrach™, 57s for the Pentax AWS S100, 53s for the LMA-guided stylet and 43s for the stylet without LMA guidance. Complete suctioning of the water from the airways was not possible with the suction system used. The Oxylator(®) connected to the demand valve ventilated at 50m depth with a mean ventilation rate of 6.5min(-1) vs. 14.7min(-1) and minute volume of 4.5lmin(-1) vs. 7.6lmin(-1) compared to the surface. The rate of chest compression at 50m was 228min(-1) vs. 106min(-1) compared to surface. The depth of compressions decreased with increasing depth. CONCLUSION: Airway management under water appears to be feasible in this manikin model. The suction system requires further modification. Mechanical ventilation at depth is possible but modifications of the Oxylator(®) are required to stabilize ventilation rate and administered minute volumes. The LUCAS™ 1 cannot be recommended at major depth

Compromised cardiopulmonary resuscitation quality due to regurgitation during endotracheal intubation: A randomised crossover manikin simulation study

Background: Regurgitation is a complication common during cardiopulmonary resuscitation (CPR). This manikin study evaluated the effect of regurgitation during endotracheal intubation on CPR quality. Methods: An airway-CPR manikin was modified to regurgitate simulated gastric contents into the oropharynx during chest compression during CPR. In total, 54 emergency medical technician-paramedics were assigned to either an oropharyngeal regurgitation or clean airway scenario and then switched to the other scenario after finishing the first. The primary outcomes were CPR quality metrics, including chest compression fraction (CCF), chest compression depth, chest compression rate, and longest interruption time. The secondary outcomes were intubation success rate and intubation time. Results: During the first CPR-intubation sequence, the oropharyngeal regurgitation scenario was associated with a significantly lower CCF (79.6% vs. 85.1%, P \u3c 0.001), compression depth (5.2 vs. 5.4 cm, P \u3c 0.001), and first-pass success rate (35.2% vs. 79.6%, P \u3c 0.001) and greater longest interruption duration (4.0 vs. 3.0 s, P \u3c 0.001) than the clean airway scenario. During the second and third sequences, no significant difference was observed in the CPR quality metrics between the two scenarios. In the oropharyngeal regurgitation scenario, successful intubation was independently and significantly associated with compression depth (hazard ratio = 0.47, 95% confidence interval, 0.24-0.91), whereas none of the CPR quality metrics were related to successful intubation in the clean airway scenario. Conclusion: Regurgitation during endotracheal intubation significantly reduces CPR quality. Trial registration: ClinicalTrials.gov, NCT05278923 , March 14, 2022

Randomized comparison of two new methods for chest compressions during CPR in microgravity-A manikin study

Background: Although there have been no reported cardiac arrests in space to date, the risk of severe medical events occurring during long-duration spaceflights is a major concern. These critical events can endanger both the crew as well as the mission and include cardiac arrest, which would require cardiopulmonary resuscitation (CPR). Thus far, five methods to perform CPR in microgravity have been proposed. However, each method seems insufficient to some extent and not applicable at all locations in a spacecraft. The aim of the present study is to describe and gather data for two new CPR methods in microgravity. Materials and methods: A randomized, controlled trial (RCT) compared two new methods for CPR in a free-floating underwater setting. Paramedics performed chest compressions on a manikin (Ambu Man, Ambu, Germany) using two new methods for a free-floating position in a parallel-group design. The first method (Schmitz-Hinkelbein method) is similar to conventional CPR on earth, with the patient in a supine position lying on the operator\u27s knees for stabilization. The second method (Cologne method) is similar to the first, but chest compressions are conducted with one elbow while the other hand stabilizes the head. The main outcome parameters included the total number of chest compressions (n) during 1 min of CPR (compression rate), the rate of correct chest compressions (%), and no-flow time (s). The study was registered on clinicaltrials.gov (NCT04354883). Results: Fifteen volunteers (age 31.0 ± 8.8 years, height 180.3 ± 7.5 cm, and weight 84.1 ± 13.2 kg) participated in this study. Compared to the Cologne method, the Schmitz-Hinkelbein method showed superiority in compression rates (100.5 ± 14.4 compressions/min), correct compression depth (65 ± 23%), and overall high rates of correct thoracic release after compression (66% high, 20% moderate, and 13% low). The Cologne method showed correct depth rates (28 ± 27%) but was associated with a lower mean compression rate (73.9 ± 25.5/min) and with lower rates of correct thoracic release (20% high, 7% moderate, and 73% low). Conclusions: Both methods are feasible without any equipment and could enable immediate CPR during cardiac arrest in microgravity, even in a single-helper scenario. The Schmitz-Hinkelbein method appears superior and could allow the delivery of high-quality CPR immediately after cardiac arrest with sufficient quality

Time to ventilation and success rate of airway devices in microgravity: A randomized crossover manikin-trial using an underwater setting

BACKGROUND: Medical support for space exploration missions must prepare for severe medical events in conditions of microgravity. A key component to managing these events is techniques of airway management. The aim of the present trial is to compare airway management devices in simulated microgravity. METHODS: In this randomized cross-over trial (RCT), four different devices were compared under simulated microgravity conditions utilizing a neutrally buoyant free-floating underwater manikin and poolside in normal gravity (control group). The primary endpoint was the successful placement of the airway device. The secondary endpoints were the number of attempts and the duration of each attempt. RESULTS: A total of 20 participants performed placement of each device in both gravity conditions in an Airway mannequin. The fastest time to initial ventilation in simulated microgravity was possible with the laryngeal tube (18.9 ± 8 seconds) followed by laryngeal mask (20.1 ± 9 seconds). The I-gel® supraglottic airway device required substantially more time for successful insertion in simulated microgravity (35.4 ± 25 seconds) as did endotracheal tube intubation by direct laryngoscopy (70.4 ± 35 seconds). Simulated microgravity conditions prolonged time to initial ventilation by 3.3 seconds (LM), 3.9 seconds (LT), 19.9 seconds (I-gel) and 43.1 seconds (endotracheal intubation, ETI) when compared to poolside attempts in normogravity. CONCLUSION: In simulated microgravity conditions, use of the laryngeal tube or laryngeal mask provided the quickest time to initial ventilation, without deliberate tethering of the mannequin and rescuer to a fixed surface. Endotracheal intubation required significantly longer procedure times and, thus, was considered insufficient for clinical use in microgravity