Simultaneous Chest Compression Research Articles

Effects of cardiopulmonary resuscitation on direct versus video laryngoscopy using a mannequin model

During the last decade, guidelines for cardiopulmonary resuscitation has shifted, placing chest compressions and defibrillation first and airway management second. Physicians are being forced to intubate simultaneously with uninterrupted, high quality chest compressions. Using a mannequin model, this study examines the differences between direct and video laryngoscopy, comparing their performance with and without simultaneous chest compressions. Fifty emergency medicine physicians were randomly assigned to intubate a mannequin six times, using direct laryngoscopy (DL) and with two video laryngoscopy (VL) systems, a C-MAC traditional Macintosh blade and a GlideScope hyperangulated blade, with and without simultaneous chest compressions. A total of 300 intubations were completed and variables including intubation times, accuracy, difficulty, success rates and glottic views were recorded. The C-MAC VL system resulted in quicker intubations compared to DL (p=0.007) and the GlideScope VL system (p=0.039) during active chest compressions. Compared to DL, intubations were rated easier for both the C-MAC (p<0.0001) and the GlideScope (p<0.0001). Intubation failure rates were also higher when DL was used compared to either the C-MAC or GlideScope (p=0.029). VL devices provided a superior overall Cormack-Lehane grade view compared to DL (p<0.0001). The presence of chest compressions significantly impaired Cormack-Lehane views during direct laryngoscopy (p=0.007). Chest compressions made the intubation more difficult under DL (p=0.002) and when using the C-MAC (p=0.031). Chest compressions also made ETT placement less accurate when using DL (p=0.004). Using a mannequin model, the C-MAC conventional VL blade resulted in decrease intubation times compared with DL or the GlideScope hyperangulated VL blade system. Overall, VL out performed DL in terms of providing a superior glottic view, minimizing failed attempts, and improving physician's overall perception of intubation difficulty. Chest compressions resulted in worse Cormack-Lehane views and higher rates of inaccurate endotracheal tube placement with DL, compared to VL.

Chest compressions during ventilation in out-of-hospital cardiopulmonary resuscitation cause fragmentation of the airflow.

When a patient suffers an out-of-hospital cardiac arrest, ventilation and chest compressions are often given simultaneously during cardiopulmonary resuscitation. These simultaneous chest compressions may cause a fragmentation of the airflow, which may lead to an ineffective ventilation. This study focusses on the occurrence and quantification of this fragmentation and its effect on ventilation. This study is a single-center observational study, held at Ghent University Hospital. A custom-built bidirectional flow sensor was used to quantify the volumes of ventilation. Adult cardiac arrest patients who were prehospitally intubated and resuscitated by the medical emergency team were eligible for inclusion. Data of the patients who were ventilated and received simultaneous chest compressions, was used to calculate the volumes of ventilation and the amount and volumes of fragmentation. All data in this study is reported as mean (standard deviation; range). Data of 10 patients (7 male) with a mean age of 71years (14;51-87) was used in this study. The mean ventilation frequency was 12/min (2;9-16), the mean minute volume and tidal volume were respectively 6.21L (1.51;3.79-8.15) and 514mL (99;422-682). Fragmentation of the airflow was observed in all patients, with an average of 3 (1;2-5) fragments per inspiration and a mean volume of 214mL (65;112-341) per fragment. Chest compressions during ventilation caused fragmentation of the airflow in all patients. There was wide variation in the number and volume of the fragments between patients. The importance of quantification of airflow volumes and the effect fragmentation of the airflow on the efficacy of ventilation can be essential in improving cardiopulmonary resuscitation techniques and therefore needs further investigation.

Regurgitation and pulmonary aspiration during cardio-pulmonary resuscitation (CPR) with a laryngeal tube: A pilot crossover human cadaver study

BackgroundHigh-quality chest compressions are imperative for Cardio-Pulmonary-Resuscitation (CPR). International CPR guidelines advocate, that chest compressions should not be interrupted for ventilation once a patient’s trachea is intubated or a supraglottic-airway-device positioned. Supraglottic-airway-devices offer limited protection against pulmonary aspiration. Simultaneous chest compressions and positive pressure ventilation both increase intrathoracic pressure and potentially enhances the risk of pulmonary aspiration. The hypothesis was, that regurgitation and pulmonary aspiration is more common during continuous versus interrupted chest compressions in human cadavers ventilated with a laryngeal tube airway.MethodsTwenty suitable cadavers were included, and were positioned supine, the stomach was emptied, 500 ml of methylene-blue-solution instilled and laryngeal tube inserted. Cadavers were randomly assigned to: 1) continuous chest compressions; or, 2) interrupted chest compressions for ventilation breaths. After 14 minutes of the initial designated CPR strategy, pulmonary aspiration was assessed with a flexible bronchoscope. The methylene-blue-solution was replaced by 500 ml barium-sulfate radiopaque suspension. 14 minutes of CPR with the second designated ventilation strategy was performed. Pulmonary aspiration was then assessed with a conventional chest X-ray.ResultsTwo cadavers were excluded for technical reasons, leaving 18 cadavers for statistical analysis. Pulmonary aspiration was observed in 9 (50%) cadavers with continuous chest compressions, and 7 (39%) with interrupted chest compressions (P = 0.75).ConclusionOur pilot study indicate, that incidence of pulmonary aspiration is generally high in patients undergoing CPR when a laryngeal tube is used for ventilation. Our study was not powered to identify potentially important differences in regurgitation or aspiration between ongoing vs. interrupted chest compression. Our results nonetheless suggest that interrupted chest compressions might better protect against pulmonary aspiration when a laryngeal tube is used for ventilation.

The SURV1VE trial\u2014sustained inflation and chest compression versus 3:1 chest compression-to-ventilation ratio during cardiopulmonary resuscitation of asphyxiated newborns: study protocol for a cluster randomized controlled trial

BackgroundThe need for cardiopulmonary resuscitation (CPR) is often unexpected, and the infrequent use of CPR in the delivery room (DR) limits the opportunity to perform rigorous clinical studies to determine the best method for delivering chest compression (CC) to newborn infants. The current neonatal resuscitation guidelines recommend using a coordinated 3:1 compression-to-ventilation (C:V) ratio (CC at a rate of 90/min and ventilations at a rate of 30/min). In comparison, providing CC during a sustained inflation (SI) (CC + SI) significantly improved hemodynamics, minute ventilation, and time to return of spontaneous circulation (ROSC) compared to 3:1 C:V ratio in asphyxiated piglets. Similarly, a small pilot trial in newborn infants showed similar results. Until now no study has examined different CC techniques during neonatal resuscitation in asphyxiated newborn infants in the DR. To date, no trial has been performed to directly compare CC + SI and 3:1 C:V ratio in the DR during CPR of asphyxiated newborn infants.MethodsThis is a large, international, multi-center, prospective, unblinded, cluster randomized controlled trial in asphyxiated newborn infants at birth. All term and preterm infants > 28+ 0 by best obstetrical estimate who require CPR at birth due to bradycardia (< 60/min) or asystole are eligible. The primary outcome of this study is to compare the time to ROSC in infants born > 28+ 0 weeks’ gestational age with bradycardia (< 60/min) or asystole immediately after birth who receive either CC + SI or 3:1 C:V ratio as the CPR strategy.DiscussionMorbidity and mortality rates are extremely high for newborns requiring CC. We believe the combination of simultaneous CC and SI during CPR has the potential to significantly improve ROSC and survival. In addition, we believe that CC + SI might improve respiratory and hemodynamic parameters and potentially minimize morbidity and mortality in newborn infants. In addition, this will be the first randomized controlled trial to examine CC in the newborn period.Trial registrationClinicalTrials.gov, NCT02858583. Registered on 8 August 2016

Crocodiles and neonatal resuscitation

Crocodiles and neonatal resuscitation

Cardiac Arrest after Complete Intratracheal Obstruction by an Aspirated Blood Clot in a Patient with Upper G-I Bleeding: A case report

Fatal airway obstruction due to the presence of blood clot occurs in a variety of clinical settings. Initial efforts to remove an airway clot, if warranted, involve suctioning, lavage, and forceps extraction through a flexible bronchoscope. If unsuccessful, further management options include rigid bronchoscopy, balloon-tip embolectomy catheter dislodgement, and the application of topical thrombolytic agents. We report a case of complete airway obstruction that developed after the aspiration of a blood clot during emergency operative vessel ligation in a 86-year-old female patient with gastric ulcer bleeding. Initial conventional suctioning was unsuccessful, in this case, due to a large firmly adherent clot. Therefore we peformed the alternative suctioning technique using suction attached directly to the existing tracheal tube in situ, with the cuff deflated. However, repeated direct tracheal suctioning alone failed to prevent cardiac arrest. Thereafter, simultaneously with several CPR chest compressions, large cylindrical clots were sucked up by direct tracheal suctioning. Presumably simultaneous chest compression has the potential advantage of creating higher airway pressures that provide effective kinetic energy to obstructing object.

Petechiae of the Baby's Skin as Differentiation Symptom of Infanticide Versus SIDS

The successive killing of three siblings by their biological mother at two-year intervals is described. The children were 367 days, 75 days and 3 years old. Although sudden infant death syndrome (SIDS) or interstitial pneumonia could not be ruled out as the cause of death in the two younger children, who were killed first, the third child exhibited discrete signs of violence in the mouth and throat area which were interpreted as proof of infanticide. All three children had petechiae of the skin of the face and throat, the upper thorax, the shoulders and the mucous membranes of the mouth. None of the children exhibited signs of a disease-related hemorrhagic tendency. After the mother was convicted of murdering the three-year-old boy by smothering in combination with compression of the thorax, she confessed to having killed the other two children in a similar manner. In the absence of hemostatic disease, the presence of petechiae of the skin extending over the entire drainage area of the Vena cava superior can be regarded as evidence of an increase in pressure in the thoracic cavity secondary to obstruction of the airways with simultaneous chest compression.

Regional blood flow during cardiopulmonary resuscitation in dogs.

We studied regional blood flow (QR) using radiolabeled microspheres in 12 anesthetized dogs during cardiopulmonary resuscitation (CPR). A circumferential vest and abdominal binder were used with a mechanical ventilator to deliver 30 simultaneous chest compressions and ventilations per minute. When this device was modified to increase aortic pressure (Pao) during compression and the aortic-to-right atrial pressure gradient (Pao-Pra) during relaxation, cerebral and myocardial QR increased significantly. These findings suggest that QR during CPR can be improved by augmenting perfusion-pressure gradients across the cerebral and coronary circulations.

Circulatory support during cardiac arrest using a pneumatic vest and abdominal binder with simultaneous high-pressure airway inflation

Animal and clinical studies suggest that blood flow during closed-chest cardiopulmonary resuscitation (CPR) results from phasic intrathoracic pressure fluctuations produced by rhythmic sternal depressions rather than from cardiac compression. Using physiologic observations made in animals and human beings during circulatory collapse and vigorous coughing, a pneumatic thoracic vest garment and abdominal binder device has been designed to emulate "cough CPR." Hemodynamic findings and microsphere regional perfusion observed during cardiac arrest and airway/vest/binder inflation are comparable to those observed during simultaneous chest compression and pulmonary ventilation CPR (SCV-CPR). Resuscitation and survival using the device has been compared to survival rates using conventional closed-chest CPR. The vest/binder apparatus significantly improved the coronary perfusion gradient and survival. Further studies are in progress to determine the clinical utility of this promising resuscitation adjunct.

Augmentation of Cerebral Perfusion by Simultaneous Chest Compression and Lung Inflation with Abdominal Binding After Cardiac Arrest in Dogs

Augmentation of Cerebral Perfusion by Simultaneous Chest Compression and Lung Inflation with Abdominal Binding After Cardiac Arrest in Dogs

Augmentation of cerebral perfusion by simultaneous chest compression and lung inflation with abdominal binding after cardiac arrest in dogs.

Recent studies have demonstrated that for the same chest compression force during mechanical cardiopulmonary resuscitation (CPR), the carotid artery-to-jugular vein pressure gradient and carotid blood flow are increased when the phasic rise of intrathoracic pressure is enhanced by abdominal binding and simultaneous ventilation at high airway pressure with each chest compression (SCV). The objective of the present study was to assess whether cerebral blood flow is also enhanced, since it is known that fluctuations in intrathoracic pressure are transmitted to the intracranial space and affect intracranial pressure (ICP). In two series of pentobarbital-anesthetized dogs, one of two CPR techniques was initiated immediately after inducing ventricular fibrillation. Brain blood flow was measured by the radiolabeled microsphere technique immediately before cardiac arrest and at 1 and 3 minutes after commencing CPR. Evidence of adequate mixing of spheres and lack of sedimentation under these low-flow conditions was verified by correlation with brain venous outflow, comparison of the arterial concentration-time profile of spheres and a nonsedimentary marker (thallium-201 in solution), and use of multiple arterial sampling sites. During SCV CPR with abdominal binding, mean carotid artery pressure (60 +/- 3 mm Hg) was higher than that during conventional CPR (25 +/- 2 mm HG). Pulsations of ICP occurred that were in phase with chest compression and greater than jugular venous pressure. Mean ICP was higher during SCV (46 +/- 2 mm Hg) than conventional CPR (20 +/- 2 mm Hg). However, the net brain perfusion pressure gradient (carotid artery pressure - ICP) was greater with SCV (14 +/- 3 mm Hg) than with conventional CPR (5 +/- 0.4 mm Hg). Cerebral blood flow was significantly greater during SCV CPR (32 +/- 7% of prearrest cerebral flow) than during conventional CPR (3 +/- 2%). We conclude that SCV CPR combined with abdominal binding substantially improved brain perfusion by enhancing cerebral perfusion pressure in this experimental model.

CPR with simultaneous compression and ventilation at high airway pressure in 4 animal models.

CPR with simultaneous chest compression and ventilation at high airway pressure (SCV-CPR) improves blood flow in some studies but not in others, perhaps because of differences in the animal models employed. To resolve such discrepancies, we compared SCV-CPR to standard CPR in 4 mechanically different canine models, using both small and large dogs and small and large compression pads. The 4 groups were: large dogs receiving chest compression through a large pad (model A), large dogs receiving chest compression through a small pad (model B), small dogs receiving chest compression through a large pad (model C), and small dogs receiving chest compression through a small pad (model D). Cardiac output (CO) during CPR was determined by a specially modified indicator dilution method. Models A, B, and C all had similar mean COs of 14 ml/min . kg body weight during standard CPR, and 27 ml/min . kg during SCV-CPR. However, in model D, there was no significant difference during standard vs. SCV-CPR, and the mean output was 33 ml/min . kg. We conclude that in models A, B, and C, little direct heart compression occurred and the higher intrathoracic pressure pulses produced by SCV-CPR improved blood flow. However it seems likely that there was effective cardiac compression in model D. In the absence of direct cardiac compression, SCV-CPR provides an alternative means of generating satisfactory flow in a mechanically appropriate animal model.

Failure of one method of simultaneous chest compression, ventilation, and abnormal binding during CPR

Some modified methods of CPR improve carotid blood flow, but there are no studies to show that these modified techniques improve survival, Accordingly, an experimental CPR technique using simultaneous chest compression, ventilation (SCV-CPR), and abdominal binding was compared to standard CPR in beagle dogs. The modified technique utilized a broad-based bellows device that was mechanically compressed, producing chest compression, delivering a volume of air to the endotracheal tube, and pressurizing an abdominal binder. The duration of ventricular fibrillation and CPR was 5 min. Five of the 6 dogs could be resuscitated with standard CPR. None of 6 dogs could be resuscitated using this modified method of SCV-CPR and abdominal binding. The aortic diastolic pressure and the diastolic gradient between the aorta and right atrium was significantly different between the 2 groups. Because these pressures relate to the coronary perfusion pressure, they may explain the discrepancy in the survival rate. This study suggests increasing carotid blood flow during CPR will not necessarily improve survival.

Pressure-synchronized cineangiography during experimental cardiopulmonary resuscitation.

Pressure-synchronized cineangiography during experimental cardiopulmonary resuscitation.

Simultaneous chest compressions and ventilation at high airway pressure during cardiopulmonary resuscitation: Chandra N, Rudikoff M, Weizfeldt M, Lancet1:175–178, (Jan) 1980

Simultaneous chest compressions and ventilation at high airway pressure during cardiopulmonary resuscitation: Chandra N, Rudikoff M, Weizfeldt M, Lancet1:175–178, (Jan) 1980

Simultaneous Chest Compression and Ventilation at High Airway Pressure during Cardiopulmonary Resuscitation

Simultaneous Chest Compression and Ventilation at High Airway Pressure during Cardiopulmonary Resuscitation

Cardiopulmonary resuscitation : Chandra N., Rudikoff M. and Weisfeldt M. L. (1980) Simultaneous chest compression and ventilation at high airway pressure during cardiopulmonary resuscitation. Lancet, 175

Cardiopulmonary resuscitation : Chandra N., Rudikoff M. and Weisfeldt M. L. (1980) Simultaneous chest compression and ventilation at high airway pressure during cardiopulmonary resuscitation. Lancet, 175