Evaluating time until ligation in a novel tourniquet - A crossover randomized-controlled trial.

INTRODUCTION AND AIM: Severe external hemorrhage is a significant reason for morbidity and mortality in adults; thus, the swift and correct application of a tourniquet by laypersons can be lifesaving. We conducted this randomized-controlled cross-over study to investigate the use of a novel tourniquet. METHODS: Participants were recruited at the Heidelberg University Hospital. Eligible participants were ≥ 18 years old with a medical background but without prior experience in applying a tourniquet. Participants were 1:1 randomized to the intervention group (PAX tourniquet) or the control group (SAM or CAT tourniquet). In the control group, participants underwent another randomization to either the SAM or CAT tourniquet without a predefined allocation ratio. Hyperspectral measurements were undertaken (i) before ligation, (ii) 30 s after ligation, and (iii) 30 s after the reopening of the tourniquet. The primary outcome was time until ligation before crossover between the respective groups. The analysis of secondary endpoints included all attempts to assess a possible learning effect, intraoperator variability, and hyperspectral measurements. Participants were crossed to the other study group after a brief wash-out phase. RESULTS: In total, 50 participants were recruited, resulting in 100 attempts. A success rate of 98% was observed across the study population. Time until ligation was 49 s and 56 s (p = 0.572) in the intervention and control group, respectively. However, there was a significant difference between the PAX and SAM (54 vs 75 s; p = 0.037) and the SAM and CAT tourniquet (75 vs. 47 s; p = 0.015). Further, we observed a significant learning effect in participants allocated to the control group first, with a median reduction of 9 s in the time until ligation. Hyperspectral measurements showed a significant decrease in perfusion and tissue oxygenation after ligation. Further, a significant increase in perfusion and tissue oxygenation was found after reopening the tourniquet compared to the baseline measurement. CONCLUSION: The novel PAX tourniquet can be applied quickly and effectively by medical personnel without prior experience in applying a tourniquet.

Severe trauma associated cardiac failure.

Although significant efforts have been made to enhance trauma care, the mortality rate for traumatic cardiac arrest (TCA) remains exceedingly high. Therefore, our institution has implemented special measures to optimize the treatment of major trauma patients. These measures include a prehospital Medical Intervention Car (MIC) and a 'code red' protocol in the trauma resuscitation room for patients with TCA or shock. These measures enable the early treatment of reversible causes of TCA and have resulted in a significant number of patients achieving adequate ROSC. However, a significant proportion of these patients still die due to circulatory failure shortly after. Our observations from patients who underwent clamshell thoracotomy or received echocardiographic evaluation in conjunction with current scientific findings led us to conclude that dysfunction of the heart itself may be the cause. Therefore, we propose discussing severe trauma-associated cardiac failure (STAC) as a new entity to facilitate scientific research and the development of specific treatment strategies, with the aim of improving the outcome of severe trauma.

Out-of-hospital cardiac arrest treated with prehospital double sequential external defibrillation during eCPR in refractory VF - a case report.

BACKGROUND: Double sequential external defibrillation (DSED) has demonstrated increased survival with good neurological outcome in a recent randomized controlled trial. DSED has not been studied in patients with extracorporeal cardiopulmonary resuscitation (eCPR). CASE: We present the first case of prehospital eCPR with ongoing refractory ventricular fibrillation (VF), terminated by DSED. After six shocks, return of spontaneous circulation was initially achieved; however, the patient went into recurrent VF. ECPR was performed prehospital, with VF still refractory after three more shocks. DSED successfully terminated VF and showed a further increase in etCO2 and near-infrared spectroscopy cerebral oximetry values. CONCLUSION: DSED can be a sufficient strategy for patients in refractory VF while on eCPR and should be evaluated in further studies.

Implementation of hyperspectral imaging in a trauma resuscitation room: a randomized controlled trial.

BACKGROUND: Hyperspectral imaging (HSI) is a novel imaging technology with the ability to assess microcirculatory impairment. We aimed to assess feasibility of performing HSI, a noninvasive, contactless method to assess microcirculatory alterations, during trauma resuscitation care. METHODS: This randomized controlled clinical trial was conducted in a dedicated trauma resuscitation room of a level one trauma center. We included adult patients who were admitted to the trauma resuscitation room. Patients were allocated in a 1:1 ratio to the HSI group (intervention) or control group. In addition to the standard of care, patients in the intervention group had two hyperspectral recordings (HSR) of their hand palm taken. Primary outcomes were the treatment duration of the primary survey (until end of ABCDE-evaluation, ultrasound and evaluation by the trauma team) and the total resuscitation room care (until transport to definitive care) as well as the ability to perform measurements from all HSR. Secondary outcomes were analyses from the intervention group compared to HSI measurements of 26 healthy volunteers including an analysis based on the ISS (Injury severity score) (< 16 vs. ≥ 16). Care givers, and those assessing the outcomes were blinded to group assignment. RESULTS: Our final analysis included 51 patients, with 25 and 26 allocated to the control and intervention group, respectively. There was a statistically significant shorter median duration of the primary survey in the control group (03:22 min [Q1-Q3 03:00-03:51]) compared to the intervention group (03:59 min [Q1-Q3 03:29-04:35]) with a difference of -37 s (95% CI -66 to -12). Total resuscitation room care was longer in the control group, but without significance: 60 s (95% CI -60 to 180). From 52 HSI, we were able to perform hyperspectral measurements on all images, with significant differences between injured patients and healthy volunteers. CONCLUSION: HSI proved to be feasible during resuscitation room care and can provide valuable information on the microcirculatory state. Trial registration DRKS DRKS00024047- www.drks.de . Registered on 13th April 2021.

Advanced and Invasive Cardiopulmonary Resuscitation (CPR) Techniques as an Adjunct to Advanced Cardiac Life Support.

BACKGROUND: Despite numerous promising innovations, the chance of survival from sudden cardiac arrest has remained virtually unchanged for decades. Recently, technological advances have been made, user-friendly portable devices have been developed, and advanced invasive procedures have been described that could improve this unsatisfactory situation. METHODS: A selective literature search in the core databases with a focus on randomized controlled trials and guidelines. RESULTS: Technical aids, such as feedback systems or automated mechanical cardiopulmonary resuscitation (CPR) devices, can improve chest compression quality. The latter, as well as extracorporeal CPR, might serve as a bridge to treatment (with extracorporeal CPR even as a bridge to recovery). Sonography may be used to improve thoracic compressions on the one hand and to rule out potentially reversible causes of cardiac arrest on the other. Resuscitative endovascular balloon occlusion of the aorta might enhance myocardial and cerebral perfusion. Minithoracostomy, pericardiocentesis, or clamshell thoracotomy might resolve reversible causes of cardiac arrest. CONCLUSIONS: It is crucial to identify those patients who may benefit from an advanced or invasive procedure and make the decision to implement the intervention in a timely manner. As with all infrequently performed procedures, sound education and regular training are paramount.

Motion and dural sac compression in the upper cervical spine during the application of a cervical collar in case of unstable craniocervical junction-A study in two new cadaveric trauma models.

BACKGROUND: Unstable conditions of the craniocervical junction such as atlanto-occipital dislocation (AOD) or atlanto-axial instability (AAI) are severe injuries with a high risk of tetraplegia or death. Immobilization by a cervical collar to protect the patient from secondary damage is a standard procedure in trauma patients. If the application of a cervical collar to a patient with an unstable craniocervical condition may cause segmental motion and secondary injury to the spinal cord is unknown. The aim of the current study is (i) to analyze compression on the dural sac and (ii) to determine relative motion of the cervical spine during the procedure of applying a cervical collar in case of ligamentous unstable craniocervical junction. METHODS AND FINDINGS: Ligamentous AOD as well as AOD combined with ligamentous AAI was simulated in two newly developed cadaveric trauma models. Compression of the dural sac and segmental angulation in the upper cervical spine were measured on video fluoroscopy after myelography during the application of a cervical collar. Furthermore, overall three-dimensional motion of the cervical spine was measured by a motion tracking system. In six cadavers each, the two new trauma models on AOD and AOD combined with AAI could be implemented. Mean dural sac compression was significantly increased to -1.1 mm (-1.3 to -0.7 mm) in case of AOD and -1.2 mm (-1.6 to -0.6 mm) in the combined model of AOD and AAI. Furthermore, there is a significant increased angulation at the C0/C1 level in the AOD model. Immense three-dimensional movement up to 22.9° of cervical spine flexion was documented during the procedure. CONCLUSION: The current study pointed out that applying a cervical collar in general will cause immense three-dimensional movement. In case of unstable craniocervical junction, this leads to a dural sac compression and thus to possible damage to the spinal cord.

Spinal movement and dural sac compression during airway management in a cadaveric model with atlanto-occipital instability.

PURPOSE: To analyze the compression of the dural sac and the cervical spinal movement during performing different airway interventions in case of atlanto-occipital dislocation. METHODS: In six fresh cadavers, atlanto-occipital dislocation was performed by distracting the opened atlanto-occipital joint capsule and sectioning the tectorial membrane. Airway management was done using three airway devices (direct laryngoscopy, video laryngoscopy, and insertion of a laryngeal tube). The change of dural sac's width and intervertebral angulation in stable and unstable atlanto-occipital conditions were recorded by video fluoroscopy with myelography. Three-dimensional overall movement of cervical spine was measured in a wireless human motion track system. RESULTS: Compared with a mean dural sac compression of - 0.5 mm (- 0.7 to - 0.3 mm) in stable condition, direct laryngoscopy caused an increased dural sac compression of - 1.6 mm (- 1.9 to - 0.6 mm, p = 0.028) in the unstable atlanto-occipital condition. No increased compression on dural sac was found using video laryngoscopy or the laryngeal tube. Moreover, direct laryngoscopy caused greater overall extension and rotation of cervical spine than laryngeal tube insertion in both stable and unstable conditions. Among three procedures, the insertion of a laryngeal tube took the shortest time. CONCLUSION: In case of atlanto-occipital dislocation, intubation using direct laryngoscopy exacerbates dural sac compression and may cause damage to the spinal cord.

Cadaveric study of movement in the unstable upper cervical spine during emergency management: tracheal intubation and cervical spine immobilisation-a study protocol for a prospective randomised crossover trial.

INTRODUCTION: Emergency management of upper cervical spine injuries often requires cervical spine immobilisation and some critical patients also require airway management. The movement of cervical spine created by tracheal intubation and cervical spine immobilisation can potentially exacerbate cervical spinal cord injury. However, the evidence that previous studies have provided remains unclear, due to lack of a direct measurement technique for dural sac's space during dynamic processes. Our study will use myelography method and a wireless human motion tracker to characterise and compare the change of dural sac's space during tracheal intubations and cervical spine immobilisation in the presence of unstable upper cervical spine injury such as atlanto-occipital dislocation or type II odontoid fracture. METHODS AND ANALYSIS: Perform laryngoscopy and intubation, video laryngoscope intubation, laryngeal tube insertion, fiberoptic intubation and cervical collar application on cadaveric models of unstable upper cervical spine injury such as atlanto-occipital dislocation or type II odontoid fracture. The change of dural sac's space and the motion of unstable cervical segment are recorded by video fluoroscopy with previously performing myelography, which enables us to directly measure dural sac's space. Simultaneously, the whole cervical spine motion is recorded at a wireless human motion tracker. The maximum dural sac compression and the maximum angulation and distraction of the injured segment are measured by reviewing fluoroscopic and myelography images. ETHICS AND DISSEMINATION: This study protocol has been approved by the Ethics Committee of the State Medical Association Rhineland-Palatinate, Mainz, Germany. The results will be published in relevant emergency journals and presented at relevant conferences. TRIAL REGISTRATION NUMBER: DRKS00010499.

Predictive value of high-sensitivity troponin I and D-dimer assays for adverse outcome in patients with acute pulmonary embolism.

High-sensitivity troponin (hs-cTn) assays enable the troponin cutoff value to be lowered, resulting in an increase of sensitivity at the cost of specificity. In the present study, the risk of a short-term adverse outcome was assessed in patients with acute pulmonary embolism (PE) using high-sensitivity troponin I (hs-cTnI). We used a cutoff value of 0.1 ng/ml in accordance with current guidelines for unstable angina (UA)/non-ST-segment elevation myocardial infarction (NSTEMI), although the detection limit of the troponin assay is lower. In addition, the risk of an adverse outcome in patients with acute PE was investigated with respect to initial D-dimer serum concentrations. In 65 patients with confirmed acute PE, hs-cTnI and D-dimer values were measured. Adverse clinical outcome was defined as cardiogenic shock, cardiopulmonary resuscitation, mechanical ventilation, vasopressor therapy, thrombolysis, catheter intervention or mortality within 60 days of PE. Patients with acute PE and serum hs-cTnI values >0.1 ng/ml showed significantly higher D-dimer concentrations (P= 0.0467) and a 5-fold increased risk of an adverse clinical outcome [odds ratio (OR), 4.9; 95% confidence interval (CI), 1.28-18.66; P=0.0235] compared with patients with acute PE and hs-cTnI values <0.1 ng/ml. In patients with acute PE suffering from adverse clinical outcome, D-dimer concentrations were significantly elevated compared with those in patients with acute PE without adverse clinical outcome (P=0.02). In patients with acute PE, a hs-cTnI cutoff value of 0.1 ng/ml, which is identical to the recommended cutoff value of NSTEMI, may identify patients with a 5-fold increased risk of a short-term adverse outcome. D-dimer values are significantly higher in PE patients with elevated hs-cTnI values as well as in patients with an adverse outcome.

Prediction of adverse clinical outcome in patients with acute pulmonary embolism: evaluation of high-sensitivity troponin I and quantitative CT parameters.

PURPOSE: To evaluate the accuracy of high-sensitivity-cardiac-troponin-I (hs-cTnI) and quantitative CT-parameters, alone and in combination, for predicting right-ventricular-dysfunction (RVD) and adverse clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS AND METHODS: 65 patients with PE and hs-cTnI measurements within 24 h of CT were retrospectively included. RVD was assessed on CT by calculating right ventricular/left ventricular (RV/LV) diameter ratios on transverse sections (RV/LVtrans), four-chamber-views (RV/LV4ch), and RV/LV volume ratio (RV/LVvol). Pulmonary CTA-obstruction-scores (OS) (Qanadli, Mastora) were calculated. Receiver operator characteristic (ROC) analysis was performed to compare Hs-cTnI, RV/LV ratios, and OS for predicting adverse clinical outcome (i.e. intensive care treatment, death). RESULTS: 12 patients with PE had adverse clinical outcome and showed significantly higher RV/LV ratios and OS compared to those without. ROC analysis revealed a cutoff value of 0.042 ng/mL for hs-cTnI resulting in a sensitivity and specificity of 84% and 92% for predicting adverse clinical outcome, respectively. Elevated hs-cTnI was significantly associated with adverse clinical outcome. In a ROC analysis the AUC for the prediction of adverse clinical outcome of RV/LV4Ch, RV/LVvol, and hs-cTnI were 0.77, 0.76, and 0.71. The combination of hs-cTnI and RV/LV ratios increased the AUC for the prediction of adverse clinical outcome. CONCLUSIONS: Hs-cTnI is associated with adverse clinical outcome in patients with acute PE. A combination of hs-cTnI with quantitative CT-parameters improves the prediction of adverse clinical outcome.