Kim OH, et al. J Korean Med Sci. 2017 Jul;32(7):1187-1194. https://doi.org/10.3346/jkms.2017.32.7.1187

Determining the cause of cardiac arrest (CA) and the heart status during CA is crucial for its treatment. Transesophageal echocardiography (TEE) is an imaging method that facilitates close observation of the heart without interfering with cardiopulmonary resuscitation (CPR). Intra-arrest TEE is a point-of-care ultrasound technique that is used during CPR. Intra-arrest TEE is performed to diagnose the cause of CA, determine the presence of cardiac contraction, evaluate the quality of CPR, assist with catheter insertion, and explore the mechanism of blood flow during CPR. The common causes of CA diagnosed using intra-arrest TEE include cardiac tamponade, aortic dissection, pulmonary embolism, and intracardiac thrombus, which can be observed on a few simple image planes at the mid-esophageal and upper esophageal positions. To operate an intra-arrest TEE program, it is necessary to secure a physician who is capable of performing TEE, provide appropriate training, establish implementation protocols, and prepare a plan in collaboration with the CPR team.

Purpose. It is important that clinicians accurately predict the outcome of patients with sudden cardiac arrest (SCA). The complete blood count (CBC) is an easy and inexpensive test that provides information on blood content. Platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR), and delta neutrophil index (DNI) are relatively novel biomarkers that have been used in the prognosis of various diseases. We aimed to determine the usefulness of PLR, NLR, and DNI in predicting the outcomes of SCA. Materials and Methods. This retrospective observational study was performed on patients with SCA. Patients who visited the tertiary university hospital from January 2015 to December 2019 were targeted. The inclusion criteria were all nontraumatic adult out-hospital cardiac arrest patients. We analyzed DNI, PLR, and NLR based on the CBC results of all enrolled patients. The exclusion criteria were as follows: no data on laboratory study, traumatic arrest, age < 18 years, and a history of leukemia, myelodysplastic syndrome, and myelofibrosis. The primary outcome was assessed as return of spontaneous circulation (ROSC), the secondary outcome as survival to discharge, and the tertiary outcome as neurological outcome. Results. From January 1, 2015, to December 31, 2019, 739 patients were enrolled. ROSC was seen in 324 patients, of whom 60 had survival to discharge and 24 had good neurological outcome at the time of discharge (cerebral performance categories (CPCs) 1-2). The PLR of the ROSC group was 42.41 (range: 4.21–508.7), which was higher than that of the No-ROSC group ( ). The DNI value of the survival group was 0.00 (range: 0.00–40.9), which was lower than that of the nonsurvival group. Conclusions. Patients with SCA and subsequent ROSC had higher PLR and NLR, while those with survival to discharge had lower DNI values than those with nonsurvival to discharge ( ).

Background: Epinephrine is administered to increase coronary perfusion pressure during advanced life support and promote short‐term survival. Recent cardiopulmonary resuscitation (CPR) guidelines recommend an epinephrine dosing interval of 3 to 5 minutes during resuscitation; however, scientific evidence supporting this recommendation is lacking. Therefore, we aimed to investigate the hemodynamic effects of repeated epinephrine doses during CPR by monitoring augmented blood pressure after its administration in a swine model of cardiac arrest. Methods and Results: A secondary analysis of data from a published study was performed using a swine cardiac arrest model. The epinephrine dose was fixed at 1 mg, and the first dose of epinephrine was administered after no‐flow and low‐flow times of 2 minutes and 8 minutes, respectively, and subsequently administered every 4 minutes. Four cycles of dosing intervals were defined because a previous study was terminated 26 minutes after the induction of ventricular fibrillation. Augmented blood pressures and corresponding timelines were determined. Augmented blood pressure trends following cycles and the epinephrine effect duration were also monitored. Among the 140 CPR cycles, the augmented blood pressure after epinephrine administration was the highest during the first cycle of CPR and decreased gradually with further cycle repetitions. The epinephrine effect duration did not differ between repeated cycles. The maximum blood pressure was achieved 78 to 97 seconds after epinephrine administration. Conclusions: Hemodynamic augmentation with repeated epinephrine administration during CPR decreased with cycle progression. Further studies are required to develop an epinephrine administration strategy to maintain its hemodynamic effects during prolonged resuscitation.

Background: There is controversy over whether the number and mode of electrical shock are optimal for successful defibrillation. Methods and Results: Fifty‐four pigs were randomly assigned to 3 groups. After inducing ventricular fibrillation and a 2‐minute downtime, basic life support was initiated with a 30:2 compression/ventilation ratio for 8 minutes. Subsequently, 20 minutes of advanced life support, including asynchronous ventilation, every 10 chest compressions with 15 L/min of oxygen, was delivered. Animals of the single shock group received a single shock, animals of the 2‐stacked shock group received 2 consecutive shocks, and animals of the 3‐stacked shock group received 3 consecutive shocks. Animals with the return of spontaneous circulation underwent post–cardiac arrest care for 12 hours. The rates of successful defibrillation, return of spontaneous circulation, 24‐hour survival, and 48‐hour survival and neurological deficit score were compared between the groups. Hemodynamic parameters, arterial blood gas profiles, troponin I, and cardiac output were not different between the groups. There was a significant difference in chest compression fraction between the single and 3‐stacked shock groups ( P <0.001), although there was no difference between the single and 2‐stacked shock groups ( P =0.022) or the 2‐stacked and 3‐stacked shock groups ( P =0.040). The rates of successful defibrillation, return of spontaneous circulation, 24‐hour survival, and 48‐hour survival were higher in the 2‐ and 3‐stacked shock groups than in the single shock group ( P =0.021, P =0.015, and P =0.021, respectively). Neurological deficit score at 48 hours was not different between the groups. Conclusions: A stacked shock strategy was superior to a single shock strategy for successful defibrillation and better resuscitation outcomes in treating ventricular fibrillation.

Distinguishing syncope from epileptic seizures in patients with sudden loss of consciousness is important. Various blood tests have been used to indicate epileptic seizures in patients with impaired consciousness. This retrospective study aimed to predict the diagnosis of epilepsy in patients with transient loss of consciousness using the initial blood test results. A seizure classification model was constructed using logistic regression, and predictors were selected from a cohort of 260 patients using domain knowledge and statistical methods. The study defined the diagnosis of seizures and syncope based on the consistency of the diagnosis made by an emergency medicine specialist at the first visit to the emergency room and the diagnosis made by an epileptologist or cardiologist at the first outpatient visit using the International Classification of Diseases 10th revision (ICD-10) code. Univariate analysis showed higher levels of white blood cells, red blood cells, hemoglobin, hematocrit, delta neutrophil index, creatinine kinase, and ammonia levels in the seizure group. The ammonia level had the highest correlation with the diagnosis of epileptic seizures in the prediction model. Therefore, it is recommended to be included in the first examination at the emergency room.