A novel CPR-assist device vs. established chest compression techniques in infant CPR: A manikin study.

INTRODUCTION: Guidelines for infant CPR recommend the two-thumb encircling hands technique (TTT) and the two-finger technique (TFT) for chest compression. Some devices have been designed to assist with infant CPR, but are often not readily available. Syringe plungers may serve as an alternative infant CPR assist device given their availability in most hospitals. In this study, we aimed to determine whether CPR using a syringe plunger could improve CPR quality measurements on the Resusci-Baby manikin compared with traditional methods of infant CPR. METHODS: Compression area with a diameter of 1 to 2 cm is recommended in previous infant CPR device researches. In this is a randomized crossover manikin study, we examined the efficacy of the Syringe Plunger Technique (SPT) which uses the plunger of the 20 ml syringe with a 2 cm diameter flat piston, commonly available in hospital, for infant External Chest Compressions (ECC). Participants performed TTT, TFT and SPT ECC on Resusci® Baby QCPR® according to 2020 BLS guidelines. RESULTS: Sixty healthcare providers participated in this project. The median (IQR) ECC depths in the TTT, TFT and SPT in the first minute were 41 mm (40-42), 40 mm (38-41) and 40 mm (39-41), respectively, with p < 0.001. The median (IQR) ECC recoil in the TTT, TFT and SPT groups in the first minute was 15% (1-93), 64% (18-96) and 53% (8-95), respectively, with p = 0.003. The result in the second minute had similar findings. The SPT had the best QCPR score and less fatigue. CONCLUSION: The performance of chest compression depth and re-rebound ratio was statistically different among the three groups. TTT has good ECC depth and depth accuracy but poor recoil. TFT is the complete opposite. SPT can achieve a depth close to TTT and has a good recoil performance as TFT. Regarding comprehensive performance, SPT obtains the highest QCPR score, and SPT is also less fatigued. SPT may be an effective alternative technique for infant CPR.

Biomechanical analysis of force distribution in one-handed and two-handed adult chest compression: a randomised crossover observational study.

INTRODUCTION: The standard method of chest compression for adults is a two-handed procedure. One-handed external chest compression (ECC) is used in some situations such as during transport of patients who had an out-of-hospital cardiac arrest, but the quality of one-handed ECC is still not well known. The distribution of force is related to the quality of chest compression and may affect the risk of injury. This study aimed to determine the differences in the quality and potential safety concern between one-handed ECC and two- handed ECC. METHODS: In this randomised crossover study, participants recruited from National Cheng Kung University Hospital and the ambulance team from the fire bureau were asked to perform one-handed and two-handed ECC on the Resusci Anne manikin according to standard 2015 ECC guidelines. The MatScan Pressure Measurement system was used to investigate the compression pressure and force distribution. RESULTS: Two-handed ECC had better results than one-handed ECC in terms of the median (IQR) depth (51.00 (41.50-54.75) mm vs 42.00 (27.00-49.00) mm, p=0.018), the proportion of depth accuracy (82.05% (13.95%-99.86%) vs 11.17% (0.00%-42.13%), p=0.028) and the proportion of incomplete recoil (0.23% (0.01%-0.44%) vs 2.42% (0.60%-4.21%), p=0.002). The maximum force (45.72 (36.10-80.84) kgf vs 35.64 (24.13-74.34) kgf, p<0.001) and ulnar-radial force difference (7.13 (-16.58 to 21.07) kgf vs 23.93 (11.19-38.74) kgf, p<0.001) showed statistically significant differences. The perceived fatigue of two-handed ECC versus one-handed ECC was 5.00 (3.00-6.00) vs 6.00 (5.00-8.00), p<0.001. CONCLUSION: The quality of one-handed ECC, based on depth and recoil, is worse than that of standard two-handed ECC. The pressure and force distribution of one-handed ECC result in greater ulnar pronation of the hand than that of two-handed ECC. One-handed ECC more easily causes operator fatigue. Acknowledging these findings and adjusting training for one-handed ECC would potentially improve the quality of cardiopulmonary resuscitation during transport.

How does the side of approach impact the force delivered during external chest compression?

BACKGROUND: We investigated the biomechanics of four external chest compression (ECC) approaches involving different sides of approach and hand placement during cardiopulmonary resuscitation (CPR). METHODS: A total of 60 participants (30 women and 30 men) with CPR certification performed standard continuous 2-min ECC on a Resusci Anne manikin with real-time feedback in four scenarios: rescuer at the manikin's right side with right hand chest contact (RsRc), rescuer at the manikin's right side with left hand chest contact (RsLc), rescuer at the manikin's left side with left hand chest contact (LsLc), and rescuer at the manikin's left side with right hand chest contact (LsRc). Pressure distribution maps of the palm, peak compression pressure, and compression forces were analysed. RESULTS: The participants' mean age, height, and weight was 24.8 ± 4.8 years, 165.8 ± 8.7 cm, and 62.7 ± 13.5 kg, respectively. Of the participants, 58 and 2 were right- and left-handed, respectively. Significant between-scenario differences were observed in ulnar-side palm pressure. Ulnar-radial pressure differences were higher in the LsLc and RsRc groups than in the LsRc and RsLc groups (0.69 ± 0.62 and 0.73 ± 050 kg/cm2 vs. 0.49 ± 0.49 and 0.50 ± 0.59 kg/cm2; respectively; p < 0.05). Ulnar-radial force differences were higher in the LsLc and RsRs groups than in the sLsLc and RsRs groups. CONCLUSIONS: The higher differences in pressure and force under the LsLc and RsRc approaches may lead to higher risks of potential injury. When performing standard-quality ECC, the LsRc and RsLc approaches, in which compression pressure and force are better distributed, may be more suitable than RsRc or LsLc.

Push-fast recommendation on performing CPR causes excessive chest compression rates, a manikin model.

BACKGROUND: Increasing chest compression rate during cardiopulmonary resuscitation can affect the workload and, ultimately, the quality of chest compression. This study examines the effects of compression at the rate of as-fast-as-you-can on cardiopulmonary resuscitation (CPR) performance. METHODS: A crossover, randomized-to-order design was used. Each participant performed chest compressions without ventilation on a manikin with 2 compression rates: 100 per minute (100-cpm) and "push as-fast-as you-can" (PF). The participants performed chest compressions at a rate of either 100-cpm or PF and subsequently switched to the other after a 50-minute rest. RESULTS: Forty-two CPR-qualified nonprofessionals voluntarily participated in the study. During the PF session, the rescuers performed CPR with higher compression rates (156.8 vs 101.6 cpm), more compressions (787.2 vs 510.8 per 5 minutes), and more duty cycles (51.0% vs 41.7%), but a lower percentage of effective compressions (47.7% vs 57.9%) and a lower compression depth (35.6 vs 38.0 mm) than they did during the 100-cpm session. The CPR quality deteriorated in numbers and percentile of effective compression since the third minute in the PF session and the fourth minute in the 100-cpm session. The percentile of compressions with adequate depth in the 100-cpm sessions was higher than that in the PF sessions during the second, third, and fourth minutes of CPR. CONCLUSION: Push-fast technique showed a significant decrease in the percentile of effective chest compression compared with the 100-cpm technique during the 5-minute hand-only CPR. The PF technique exhibited a trend toward increased fatigue in the rescuers, which can result in early decay of CPR quality.

Prognostic values of blood ammonia and partial pressure of ammonia on hospital arrival in out-of-hospital cardiac arrests.

PURPOSES: Outcome prediction for out-of-hospital cardiac arrest (OHCA) is of medical, ethical, and socioeconomic importance. We hypothesized that blood ammonia may reflect tissue hypoxia in OHCA patients and conducted this study to evaluate the prognostic value of ammonia for the return of spontaneous circulation (ROSC). METHODS: This prospective, observational study was conducted in a tertiary university hospital between January 2008 and December 2008. The subjects consisted of OHCA patients who were sent to the emergency department (ED). The primary outcome was ROSC. The prognostic values were calculated for ammonia levels and the partial pressure of ammonia (pNH(3)), and the results were depicted as a receiver operating characteristics curve with an area under the curve. RESULTS: Among 119 patients enrolled in this study, 28 patients (23.5%) achieved ROSC. Ammonia levels and pNH(3) in the non-ROSC group were significantly higher than those in the ROSC group (167.0 µmol/L vs 80.0 µmol/L, P < .05; 2.61 × 10(-5) vs 1.67 × 10(-5) mm Hg, P < .05, respectively). The predictive capacity of area under the curve for ammonia and pNH(3) for non-ROSC was 0.85 (95% confidence interval, 0.75-0.95) and 0.73 (95% confidence interval, 0.61-0.84), respectively. The multivariate analysis confirmed that ammonia and pNH(3) are independent predictors of non-ROSC. The prognostic value of ammonia was better than that of pNH(3). The cutoff level for ammonia of 84 µmol/L was 94.5% sensitive and 75.0% specific for predicting non-ROSC with a diagnostic accuracy of 89.9%. CONCLUSIONS: Hyperammonemia on ED arrival is independently predictive of non-ROSC for OHCA patients. The findings may offer useful information for clinical management.

Effect of thoracic stiffness on chest compression performance - A prospective randomized crossover observational manikin study.

Introduction: Human thoracic stiffness varies and may affect the performance during external chest compression (ECC). The Extra Compression Spring Resusci® QCPR Anne manikin is a high-fidelity training model developed for ECC training that can account for varying levels of thoracic stiffness. The aim of this study was to use this training model to investigate the effects of thoracic stiffness on ECC biomechanics and qualities. Methods: Fifty-two participants performed standard ECC on the manikin with different thoracic springs to simulate varying levels of thoracic stiffness. The MatScan Pressure Measurement system was used to investigate the ECC pressure and force distribution. Results: The hard spring group's performance had a better complete recoil ratio (90.06 ± 24.84% vs. 79.75 ± 32.17% vs. 56.42 ± 40.15%, p < 0.001 at second minute), but was more inferior than the standard and soft spring groups in overall quality, ECC depth (34.17 ± 11.45 mm vs. 41.25 ± 11.42 mm vs. 51.88 ± 7.56, p < 0.001 at second minutes), corrected depth ratio, and corrected rate ratio. The hard spring group had less radial-ulnar peak pressure difference (kgf/cm2) than the other two groups (-0.28 ± 0.38 vs. -0.30 ± 0.43 vs. -0.47 ± 0.34, p = 0.01), demonstrating that more symmetrical pressure was applied in the hard spring group. The soft spring group had better ECC depth, corrected depth ratio, corrected rate ratio, and overall quality, but its performance in complete recoil was inferior, and unbalanced pressure was more liable to cause injury. Hard springs caused operator fatigue easily. Conclusion: The thoracic stiffness greatly affected the performance of ECC. Our findings provided information for more effective ECC practices and training.

Biomechanics of two-thumb versus two-finger chest compression for cardiopulmonary resuscitation in an infant manikin model.

OBJECTIVE: The loading force applied in infant external chest compression (ECC) has not been determined. The objective of this crossover study was to quantify the actual force involved in two-thumb (TT)-encircling hands and two-finger (TF) methods during infant cardiopulmonary resuscitation. METHODS: A total of 42 emergency medical professionals performed lone rescuer infant external chest compression (ECC) with TF and TT methods. The order of two methods was arranged randomly, with an interval of 30 min in between. The force was collected by MatScan as primary outcomes. The secondary outcomes, quality of chest compressions, and fatigue level were also recorded by SkillReporter and perceived exertion scale. RESULTS: Using the TT method, the rescuers performed cardiopulmonary resuscitation (CPR) with higher ECC quality, but more incomplete recoil than they did using the TF method. The mean compression forces delivered in the first and second minutes were 3.53 ± 1.27 kg and 3.22 ± 1.11 kg (P = 0.012) for TF and 4.11 ± 1.80 kg and 4.04 ± 1.83 kg (P = 0.568) for TT, respectively. Pairwise comparison indicates that the compression force delivered through the TF method during the first and second minute of ECC were inferior to that delivered through the TT method. The TF method involved greater perceived exertion than the TT method (5.27 ± 4.69 vs. 4.02 ± 2.31; P = 0.007). The median perceived exertions for the TF and TT methods were 5 and 4, respectively. CONCLUSION: For infant CPR, the TT method involved greater loading force, lower fatigue, and higher overall ECC quality than the TF method. The optimal compression force is about 3.8-4.3 kg.

Hepatic portal venous gas induced by emphysematous pyelonephritis: a rare case in hemodialytic women.

Hepatic portal venous gas (HPVG) became more easily diagnosed after the advent of abdominal computed tomography scan in the emergency department. However, the clinical significance of HPVG is popularly discussed; and its etiology remains uncertain. In this report, we present a 49- year-old diabetic, hemodialytic woman who presented with afebrile flank pain and a significant HPVG detected on abdominal computed tomography, which implied a unilateral perirenal abscess (so-called emphysematous pyelonephritis). This patient received percutaneous drainage and antibiotics therapy without emergency laparotomy intervention. No evidence of existing mesenteric infarction or bowel obstruction was detected during admission, and the patient was discharged with an uneventful outcome. To our knowledge, this is the first case of HPVG that originated from emphysematous pyelonephritis and was treated by successful emergency drainage.

Factors Associated with Blood Culture Contamination in the Emergency Department: Critical Illness, End-Stage Renal Disease, and Old Age.

BACKGROUND: Blood culture contamination in emergency departments (ED) that experience a high volume of patients has negative impacts on optimal patient care. It is therefore important to identify risk factors associated with blood culture contamination in EDs. METHODOLOGY/PRINCIPAL FINDINGS: A prospectively observational study in a university-affiliated hospital were conducted between August 2011 and December 2012. Positive monomicrobial and negative blood cultures drawn from adult patients in the ED were analyzed to evaluate the possible risk factors for contamination. A total of 1,148 positive monomicrobial cases, 391 contamination cases, and 13,689 cases of negative blood culture were identified. Compared to patients with negative blood cultures, patients in triage levels 1 and 2 (Incidence Rate Ratio, IRR = 2.24), patients with end-stage renal disease (ESRD) (IRR = 2.05), and older patients (IRR: 1.02 per year) were more likely to be associated with ED blood culture contamination. CONCLUSIONS/SIGNIFICANCE: Critical patients (triage levels 1 and 2), ESRD patients, and older patients were more commonly associated with blood culture contamination in the ED. Further studies to evaluate whether the characteristics of skin commensals contribute to blood culture contamination is warranted, especially in hospitals populated with high-risk patients.

Acute aortic dissection associated with left ventricular dysfunction in a postpartum and normotensive young woman.

Aortic dissection is uncommon in young women and is associated with clinical conditions such as pregnancy and Marfan's syndrome. Owing to the low incidence, diagnosis of acute aortic dissection in young women might be missed or delayed in patients who have neither risk factors nor typical clinical manifestations. We report the case of a 28-year-old postpartum woman with aortic dissection. The patient complained of abdominal discomfort, transient back pain, and general malaise at our emergency department 1 week after delivery of a healthy baby. She had no history of hypertension, connective tissue disease or congenital heart disease. Cardiovascular insult was not considered until the patient developed shock. Myocarditis or peripartum cardiomyopathy with left ventricular dysfunction was diagnosed based on imaging studies and cardiac enzyme levels. Finally, computed tomography revealed acute aortic dissection after hemodynamic collapse occurred. This case suggests that acute aortic dissection can be associated with left ventricular dysfunction, and non-specific clinical symptoms in young, normotensive, and postpartum women. A high index of clinical suspicion and alertness are needed to identify this condition.