Acute phlegmonous esophagitis presenting as chest pain: A case report.

RATIONALE: Acute phlegmonous esophagitis (APE) is bacterial infection of the submucosal and muscularis layers of the esophagus. APE is a rare but life-threatening disease, and few studies have reported it. PATIENT CONCERNS: A 63-year-old Korean woman was admitted to the emergency department complaining of chest pain. Contrast-enhanced computed tomography revealed diffuse esophageal wall thickening with low attenuation and paraesophageal fluid collection in the mediastinum. Esophagomyotomy, mediastinal abscess drainage with a right thoracotomy, and left 3-port video-assisted thoracoscopy were performed in the operating room. DIAGNOSES: Contrast-enhanced computed tomography revealed diffuse esophageal wall thickening with low attenuation and paraesophageal fluid collection in the mediastinum. INTERVENTIONS: Esophagomyotomy, mediastinal abscess drainage with a right thoracotomy, and left 3-port video-assisted thoracoscopy were performed in the operating room. OUTCOMES: The patient followed up through an outpatient visit 4 days later discharged. The patient progress was good, and she decided to visit the patient if she had pain afterwards. LESSONS: As APE is rare but deadly, strategies to identify APE in patients with chest pain or dysphagia are needed in emergency department.

Mortality Cases of Mushroom Poisoning with Russula subnigricans.

Mushroom poisoning is increasing worldwide, as well as the incidence of fatal mushroom poisoning. Several new syndromes associated with mushroom poisoning have been described in the literature. Notably, 1 of the newly identified mushroom poisonings is Russula subnigricans poisoning. R subnigricans can be classified as causing a delayed-onset rhabdomyolytic syndrome as patients with this severe poisoning present with severe rhabdomyolysis, acute kidney injury, and cardiomyopathy. However, there are only a few reports on the toxicity of R subnigricans. We recently treated 6 patients with R subnigricans mushroom poisoning, of whom 2 died. The 2 patients showed severe rhabdomyolysis, metabolic acidosis, acute renal failure, electrolyte imbalance, and irreversible shock, which caused their deaths. Mushroom poisoning should be considered in the evaluation of rhabdomyolysis of unknown origin. In addition, in cases of mushroom poisoning with severe rhabdomyolysis, R subnigricans poisoning should be promptly identified.

Comparison of blood flow between two mechanical compression devices using ultrasound: Animal trial.

BACKGROUND: During manual chest compression, maintaining accurate compression depth and consistency is a challenge. Therefore, mechanical chest compression devices(mCCDs) have been increasingly incorporated in clinical practice. Evaluation and comparison of the efficacy of these devices is critical for extensive clinical application. Hence, this study compared the cardiopulmonary resuscitation(CPR) efficiency of two chest compression devices, LUCAS™ 3(Physio-Control, Redmond, USA) and Easy Pulse (Schiller Medizintechnik GMBH, Feldkirchen, Germany), in terms of blood flow using ultrasonography(USG) in a swine model. METHODS: A swine model was used to compare two mCCDs, LUCAS™ 3 and Easy Pulse. Cardiac arrest was induced by injecting potassium chloride(KCl) solution in eight male mongrel pigs and the animals were randomly divided into two groups. Mechanical CPR was provided to two groups using LUCAS™ 3(LUCAS™ 3 group) and Easy Pulse(Easy Pulse group). USG was used to measure hemodynamic parameters including femoral peak systolic velocity(PSV) and femoral artery diameters(diameter during systole and diastole). Blood flow rate was calculated by multiplying the PSV and cross-sectional area of the femoral artery during systole. The end-tidal carbon dioxide(EtCo2), chest compression depth was measured. Systolic blood pressure, mean blood pressure, and diastolic blood pressure were also measured using an arterial catheter. RESULTS: The chest compression depth was much deeper in LUCAS™ 3 group than Easy Pulse group(LUCAS™ 3: 6.80 cm; Easy Pulse: 3.279 cm, p < 0.001). However, EtCo2 was lower in the LUCAS™ 3 group(LUCAS™ 3: 19.8 mmHg; Easy Pulse: 33.4 mmHg, p < 0.001). The PSV was higher in the LUCAS™ 3 group(LUCAS™ 3: 67.6 cm s-1; Easy Pulse: 55.0 cm s-1, p < 0.001), while the systolic(LUCAS™ 3: 1.5 cm; Easy Pulse: 2.0 cm, p < 0.001) and diastolic diameters were larger in the Easy Pulse group(LUCAS™ 3: 0.4; Easy Pulse: 0.8 cm, p < 0.001). The femoral flood flow rate was also lower in the LUCAS™ 3 group(LUCAS™ 3: 32.55 cm3/s; Easy Pulse: 61.35 cm3/s, p < 0.001). CONCLUSION: The Easy Pulse had a shallower compression depth and slower PSV but had a wider systolic diameter in the femoral artery as compared to that in LUCAS™ 3. Blood flow and EtCo2 were higher in the easy pulse group probably because of the wider diameter. Therefore, an easy pulse may create and maintain more effective intrathoracic pressure.

Russula subnigricans Poisoning Causes Severe Rhabdomyolysis That Could be Misdiagnosed as Non-ST Segment Elevation Myocardial Infarction.

Mushroom poisoning and subsequently the number of patients visiting emergency rooms are increasing, as well as the proportion of fatal mushroom poisonings. Myocytic mushroom poisoning is one of the new clinical classifications. This report documents the course of a family with Russula subnigricans poisoning complicated by severe rhabdomyolysis, including a case that was misdiagnosed as myocardial infarction. A 64-y-old man visited our hospital with symptoms including substernal chest discomfort, nausea, vomiting, and myalgia, lasting for 12 h. His laboratory tests showed elevated serum high-sensitive troponin I. He was diagnosed with non-ST segment elevation myocardial infarction. After that, 2 family members who ate mushrooms together were transferred from a local emergency room with the diagnosis of rhabdomyolysis. Consequently, rhabdomyolysis due to mushroom poisoning was diagnosed. They were hospitalized in the intensive care unit. After admission, conservative management, including primary fluid resuscitation, was performed, and the patients were discharged without complications. R subnigricans poisoning was revealed after investigation and should be considered in mushroom poisoning with rhabdomyolysis. Early recognition and intensive supportive care are important for mushroom poisoning patients.

Pre-hospital modified shock index for prediction of massive transfusion and mortality in trauma patients.

BACKGROUND: Modified shock index (MSI) is a useful predictor in trauma patients. However, the value of prehospital MSI (preMSI) in trauma patients is unknown. The aim of this study was to investigate the accuracy of preMSI in predicting massive transfusion (MT) and hospital mortality among trauma patients. METHODS: This was a retrospective, observational, single-center study. Patients presenting consecutively to the trauma center between January 2016 and December 2017, were included. The predictive ability of both prehospital shock index (preSI) and preMSI for MT and hospital mortality was assessed by calculating the areas under the receiver operating characteristic curves (AUROCs). RESULTS: A total of 1007 patients were included. Seventy-eight (7.7%) patients received MT, and 30 (3.0%) patients died within 24 h of admission to the trauma center. The AUROCs for predicting MT with preSI and preMSI were 0.773 (95% confidence interval [CI], 0.746-0.798) and 0.765 (95% CI, 0.738-0.791), respectively. The AUROCs for predicting 24-hour mortality with preSI and preMSI were 0.584 (95% CI, 0.553-0.615) and 0.581 (95% CI, 0.550-0.612), respectively. CONCLUSIONS: PreSI and preMSI showed moderate accuracy in predicting MT. PreMSI did not have higher predictive power than preSI. Additionally, in predicting hospital mortality, preMSI was not superior to preSI.

Changes in Relative Importance of the 5-Level Triage System, Korean Triage and Acuity Scale, for the Disposition of Emergency Patients Induced by Forced Reduction in Its Level Number: a Multi-Center Registry-based Retrospective Cohort Study.

BACKGROUND: The 5-level triage tool, the Korean Triage and Acuity Scale (KTAS), was developed based on the Canadian Triage and Acuity Scale and has been used for triage in all emergency medical institutions in Korea since 2016. This study evaluated the association between the decrease in level number and the change in its relative importance for disposition in the emergency department (ED). METHODS: Using the registry of the National Emergency Department Information System (NEDIS) ver. 3.1, data regarding consecutive emergency patients from March 2017 to October 2017 were reviewed retrospectively. Reconfiguring KTAS levels, a total of 15 multinomial logistic regression models (KTAS_0 to KTAS_14), including the KTAS, its variants, and covariates were constructed to determine significant factors affecting ED disposition. The relative importance of each model was obtained using a dominance analysis. RESULTS: A total of 79,771 patients were included in the analysis. In the model KTAS_0, the KTAS and 8 covariates were found to be significantly related to ED disposition. The KTAS and the decision maker of each ED visit, whether it was the physician or others, had the largest relative importance, 34.8% and 31.4%, respectively (P < 0.001). In other models of KTAS variants, including 4-level, 3-level and 2-level, the rates of the KTAS decreased to 31.8% (interquartile range [IQR], 28.9-34.2), 26.4% (IQR, 23.2-31.0), and 18.7% (IQR, 7.5-24.9), respectively (P = 0.016). On the other hand, the rates for covariates tended to be larger for smaller triage levels and so there was a significant interaction effect between the KTAS and the covariates according to the triage level (P < 0.001). CONCLUSION: The 5-level triage tool, the KTAS, had the largest relative importance among the predictors affecting ED disposition only at its original level. Therefore, it is recommended that no attempt should be made to reduce the number of levels in the triage tool.

Usefulness of ultrasonography for the evaluation of catheter misplacement and complications after central venous catheterization.

Objective: To assess whether ultrasonographic examination compared to chest radiography (CXR) is effective for evaluating complications after central venous catheterization. Methods: We performed a prospective observational study. Immediately after central venous catheter insertion, we asked the radiologic department to perform a portable CXR scan. A junior and senior medical resident each performed ultrasonographic evaluation of the position of the catheter tip and complications such as pneumothorax and pleural effusion (hemothorax). We estimated the time required for ultrasound (US) and CXR. Results: Compared to CXR, US could equivalently identify the catheter tip in the internal jugular or subclavian veins (P=1.000). Compared with CXR, US examinations conducted by junior residents could equivalently evaluate pneumothorax (P=1.000), while US examinations conducted by senior residents could also equivalently evaluate pneumothorax (P=0.557) and pleural effusion (P=0.337). The required time for US was shorter than that for CXR (P<0.001). Conclusion: Compared to CXR, US could equivalently and more quickly identify complications such as pneumothorax or pleural effusion.

Multiple cerebral infarct with cerebral vasculitis in a young patient with ulcerative colitis.

Ulcerative colitis (UC) is a chronic and debilitating disorder, characterized by inflammation of the colonic mucosa. UC can be considered a systemic disorder but UC-related manifestations in the central nervous system (CNS) are quite rare. A 29-year-old man was admitted to the emergency department with repeated generalized tonic-clonic (GTC) type seizures. Based on brain CT, brain metastasis or hemorrhagic infarct was suspected. Diffusion-weighted image of brain MRI showed high signal in the left thalamus and heterogenous enhancement in the right parietal and left frontal lobes. This image indicated a cerebral infarct, but could not completely rule out cerebral metastasis and vasculitis, or any other pathology. However, the brain biopsy revealed multiple thromboemboli with acute inflammation and necrosis. Thus, the patient was diagnosed with multiple cerebral infarcts with cerebral vasculitis, occurring as a complication of UC. In conclusion, CNS manifestations of UC are rare. However, clinicians should consider uncommon diagnoses like vasculitis and thromboembolism in patients with UC presenting with seizures.

Extension of a coronary intramural hematoma after blunt chest trauma.

Coronary artery dissection and intramural hematoma after blunt chest trauma are rare, but life-threatening, complications. Coronary intramural hematoma extension is even rarer. A 31-year-old man was transferred to our hospital for worsening left chest pain during while he was admitted at a nearby hospital due to blunt chest trauma. Bedside echocardiography showed akinesis of the left ventricular apex and anterior wall as well as hypokinesis of the mid-to-basal anteroseptal wall and mid-to-basal lateral and posterior walls of the left ventricle. Computed tomography coronary angiography revealed intramural hematoma in the left main (LM) coronary and proximal left anterior descending (LAD) arteries. Percutaneous coronary intervention, with bare metal stent implantation from the LM coronary artery to the proximal LAD artery, was performed to treat the occlusion caused by the hematoma. After stenting, the hematoma that compressed the LM coronary artery shifted the left circumflex (LCX) artery, and the intramural hematoma developed and extended to the LCX artery. To resolve this occlusion, a drug-eluting stent was successfully implanted in the LCX artery. The patient was discharged without complications. At 2-month follow-up, he remained asymptomatic, with no recurrence of cardiovascular symptoms. Delayed chest pain after trauma should be suspected during coronary dissection, and on treatment, care must be taken to extend the hematoma.

Usefulness of Rotational Thromboelastometry as a Mortality Predictor of Hyperfibrinolysis in Patients with Severe Trauma.

BACKGROUND: Hemorrhage is the major cause of traumatic death and the leading cause of preventable death. Hyperfibrinolysis is associated with trauma severity. Viscoelastic hemostatic assays show complete clot formation dynamics. The present study was designed to identify the relationship between hyperfibrinolysis and mortality, metabolic acidosis, and coagulopathy in patients with trauma. METHODS: Patients with severe trauma (injury severity score [ISS] of 15 or higher) who were assessed using rotational thromboelastometry (ROTEM) were included in the present study from January 2017 to December 2017. Variables were obtained from the Korea Trauma Database or the medical charts of the patients. To identify whether hyperfibrinolysis is an independent predictor of mortality, univariate and multivariate Cox regression analyses were performed. RESULTS: During the 1-year study period, 190 patients were enrolled. In total, 21 (11.1%) had hyperfibrinolysis according to the ROTEM analysis and 46 (24.2%) died. Patients with hyperfibrinolysis had a higher ISS (P=0.014) and mortality rate (P<0.001) than did those without hyperfibrinolysis. In multivariate Cox analysis, hyperfibrinolysis (hazard ratio [HR], 4.960; 95% confidence interval [CI], 2.447 to 10.053), age (HR, 1.033; 95% CI, 1.013 to 1.055), lactic acid level (HR, 1.085; 95% CI, 1.003 to 1.173), and ISS (HR, 1.037; 95% CI, 1.004 to 1.071) were independent predictors of mortality. CONCLUSIONS: Hyperfibrinolysis is associated with increased mortality, worse metabolic acidosis, and severe coagulopathy and is an independent predictor of mortality in patients with trauma.

The effect of hydraulic bed movement on the quality of chest compressions.

OBJECTIVES: The hydraulic height control systems of hospital beds provide convenience and shock absorption. However, movements in a hydraulic bed may reduce the effectiveness of chest compressions. This study investigated the effects of hydraulic bed movement on chest compressions. MATERIALS AND METHODS: Twenty-eight participants were recruited for this study. All participants performed chest compressions for 2min on a manikin and three surfaces: the floor (Day 1), a firm plywood bed (Day 2), and a hydraulic bed (Day 3). We considered 28 participants of Day 1 as control and each 28 participants of Day 2 and Day 3 as study subjects. The compression rates, depths, and good compression ratios (>5-cm compressions/all compressions) were compared between the three surfaces. RESULTS: When we compared the three surfaces, we did not detect a significant difference in the speed of chest compressions (p=0.582). However, significantly lower values were observed on the hydraulic bed in terms of compression depth (p=0.001) and the good compression ratio (p=0.003) compared to floor compressions. When we compared the plywood and hydraulic beds, we did not detect significant differences in compression depth (p=0.351) and the good compression ratio (p=0.391). CONCLUSIONS: These results indicate that the movements in our hydraulic bed were associated with a non-statistically significant trend towards lower-quality chest compressions.

Factors affecting the urologist's decision to administer ureteral stone therapy: a retrospective cohort study.

OBJECTIVE: We aimed to evaluate the factors influencing treatment option selection among urologists for patients with ureteral stones, according to the stone diameter and location. METHODS: We retrospectively reviewed the records of 360 consecutive patients who, between January 2009 and June 2014, presented to the emergency department with renal colic and were eventually diagnosed with urinary stones via computed tomography. The maximal horizontal and longitudinal diameter and location of the stones were investigated. We compared parameters between patients who received urological intervention (group 1) and those who received medical treatment (group 2). RESULTS: Among the 360 patients, 179 (49.7%) had stones in the upper ureter and 181 (50.3%) had stones in the lower ureter. Urologic intervention was frequently performed in cases of upper ureteral stones (P<0.001). In groups 1 and 2, the stone horizontal diameters were 5.5 mm (4.8 to 6.8 mm) and 4.0 mm (3.0 to 4.6 mm), stone longitudinal diameters were 7.5 mm (6.0 to 9.5 mm) and 4.4 mm (3.0 to 5.5 mm), and ureter diameters were 6.4 mm (5.0 to 8.0 mm) and 4.7 mm (4.0 to 5.3 mm), respectively (P<0.001). The cut-off values for the horizontal and longitudinal stone diameters in the upper ureter were 4.45 and 6.25 mm, respectively (sensitivity 81.3%, specificity 91.4%); those of the lower ureter were 4.75 and 5.25 mm, respectively (sensitivity 79.4%, specificity 79.4%). CONCLUSION: The probability of a urologic intervention was higher for patients with upper ureteral stones and those with stone diameters exceeding 5 mm horizontally and 6 mm longitudinally.

Comparison between an instructor-led course and training using a voice advisory manikin in initial cardiopulmonary resuscitation skill acquisition.

OBJECTIVE: We compared training using a voice advisory manikin (VAM) with an instructor-led (IL) course in terms of acquisition of initial cardiopulmonary resuscitation (CPR) skills, as defined by the 2010 resuscitation guidelines. METHODS: This study was a randomized, controlled, blinded, parallel-group trial. We recruited 82 first-year emergency medical technician students and distributed them randomly into two groups: the IL group (n=41) and the VAM group (n=37). In the IL-group, participants were trained in "single-rescuer, adult CPR" according to the American Heart Association's Basic Life Support course for healthcare providers. In the VAM group, all subjects received a 20-minute lesson about CPR. After the lesson, each student trained individually with the VAM for 1 hour, receiving real-time feedback. After the training, all subjects were evaluated as they performed basic CPR (30 compressions, 2 ventilations) for 4 minutes. RESULTS: The proportion of participants with a mean compression depth ≥50 mm was 34.1% in the IL group and 27.0% in the VAM group, and the proportion with a mean compression depth ≥40 mm had increased significantly in both groups compared with ≥50 mm (IL group, 82.9%; VAM group, 86.5%). However, no significant differences were detected between the groups in this regard. The proportion of ventilations of the appropriate volume was relatively low in both groups (IL group, 26.4%; VAM group, 12.5%; P=0.396). CONCLUSION: Both methods, the IL training using a practice-while-watching video and the VAM training, facilitated initial CPR skill acquisition, especially in terms of correct chest compression.

Optimal chest compression rate in cardiopulmonary resuscitation: a prospective, randomized crossover study using a manikin model.

OBJECTIVES: When performing cardiopulmonary resuscitation (CPR), the 2010 American Heart Association guidelines recommend a chest compression rate of at least 100 min, whereas the 2010 European Resuscitation Council guidelines recommend a rate of between 100 and 120 min. The aim of this study was to examine the rate of chest compression that fulfilled various quality indicators, thereby determining the optimal rate of compression. METHODS: Thirty-two trainee emergency medical technicians and six paramedics were enrolled in this study. All participants had been trained in basic life support. Each participant performed 2 min of continuous compressions on a skill reporter manikin, while listening to a metronome sound at rates of 100, 120, 140, and 160 beats/min, in a random order. Mean compression depth, incomplete chest recoil, and the proportion of correctly performed chest compressions during the 2 min were measured and recorded. RESULTS: The rate of incomplete chest recoil was lower at compression rates of 100 and 120 min compared with that at 160 min (P=0.001). The numbers of compressions that fulfilled the criteria for high-quality CPR at a rate of 120 min were significantly higher than those at 100 min (P=0.016). CONCLUSION: The number of high-quality CPR compressions was the highest at a compression rate of 120 min, and increased incomplete recoil occurred with increasing compression rate. However, further studies are needed to confirm the results.

Does cardiac catheterization laboratory activation by electrocardiography machine auto-interpretation reduce door-to-balloon time?

OBJECTIVES: In an attempt to begin ST-segment elevation myocardial infarction (STEMI) treatment more quickly (referred to as door-to-balloon [DTB] time) by minimizing preventable delays in electrocardiogram (ECG) interpretation, cardiac catheterization laboratory (CCL) activation was changed from activation by the emergency physician (code heart I) to activation by a single page if the ECG is interpreted as STEMI by the ECG machine (ECG machine auto-interpretation) (code heart II). We sought to determine the impact of ECG machine auto-interpretation on CCL activation. METHODS: The study period was from June 2010 to May 2012 (from June to November 2011, code heart I; from December 2011 to May 2012, code heart II). All patients aged 18 years or older who were diagnosed with STEMI were evaluated for enrollment. Patients who experienced the code heart system were also included. Door-to-balloon time before and after code heart system were compared with a retrospective chart review. In addition, to determine the appropriateness of the activation, we compared coronary angiography performance rate and percentage of STEMI between code heart I and II. RESULTS: After the code heart system, the mean DTB time was significantly decreased (before, 96.51 ± 65.60 minutes; after, 65.40 ± 26.40 minutes; P = .043). The STEMI diagnosis and the coronary angiography performance rates were significantly lower in the code heart II group than in the code heart I group without difference in DTB time. CONCLUSION: Cardiac catheterization laboratory activation by ECG machine auto-interpretation does not reduce DTB time and often unnecessarily activates the code heart system compared with emergency physician-initiated activation. This system therefore decreases the appropriateness of CCL activation.

Acupuncture as analgesia for non-emergent acute non-specific neck pain, ankle sprain and primary headache in an emergency department setting: a protocol for a parallel group, randomised, controlled pilot trial.

INTRODUCTION: This study aims to assess the feasibility of acupuncture as an add-on intervention for patients with non-emergent acute musculoskeletal pain and primary headache in an emergency department (ED) setting. METHODS AND ANALYSIS: A total of 40 patients who present to the ED and are diagnosed to have acute non-specific neck pain, ankle sprain or primary headache will be recruited by ED physicians. An intravenous or intramuscular injection of analgesics will be provided as the initial standard pain control intervention for all patients. Patients who still have moderate to severe pain after the 30 min of initial standard ED management will be considered eligible. These patients will be allocated in equal proportions to acupuncture plus standard ED management or to standard ED management alone based on computer-generated random numbers concealed in opaque, sealed, sequentially numbered envelopes. A 30 min session of acupuncture treatment with manual and/or electrical stimulation will be provided by qualified Korean medicine doctors. All patients will receive additional ED management at the ED physician's discretion and based on each patient's response to the allocated intervention. The primary outcome will be pain reduction measured at discharge from the ED by an unblinded assessor. Adverse events in both groups will be documented. Other outcomes will include the patient-reported overall improvement, disability due to neck pain (only for neck-pain patients), the treatment response rate, the use of other healthcare resources and the patients' perceived effectiveness of the acupuncture treatment. A follow-up telephone interview will be conducted by a blinded assessor 72±12 h after ED discharge. ETHICS AND DISSEMINATION: Written informed consent will be obtained from all participants. The study has been approved by the Institutional Review Boards (IRBs). The results of this study will guide a full-scale randomised trial of acupuncture in an ED context. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT02013908.

A 10-s rest improves chest compression quality during hands-only cardiopulmonary resuscitation: a prospective, randomized crossover study using a manikin model.

OBJECTIVES: This study was designed to assess changes in cardiopulmonary resuscitation (CPR) quality and rescuer fatigue when rescuers are provided with a break during continuous chest compression CPR (CCC-CPR). METHODS: The present prospective, randomized crossover study involved 63 emergency medical technician trainees. The subjects performed three different CCC-CPR methods on a manikin model. The first method was general CCC-CPR without a break (CCC), the second included a 10-s break after 200 chest compressions (10/200), and the third included a 10-s break after 100 chest compressions (10/100). All methods were performed for 10 min. We counted the total number of compressions and those with appropriate depth every 1 min during the 10 min and measured mean compression depth from the start of chest compressions to 10 min. RESULTS: The 10/100 method showed the deepest compression depth, followed by the 10/200 and CCC methods. The mean compression depth showed a significant difference after 5 min had elapsed. The percentage of adequate compressions per min was calculated as the proportion of compressions with appropriate depth among total chest compressions. The percentage of adequate compressions declined over time for all methods. The 10/100 method showed the highest percentage of adequate compressions, followed by the 10/200 and CCC methods. CONCLUSION: When rescuers were provided a rest at a particular time during CCC-CPR, chest compression quality increased compared with CCC without rest. Therefore, we propose that a rescuer should be provided a rest during CCC-CPR, and specifically, we recommend a 10-s rest after 100 chest compressions.