- Email: [email protected]
Quantitative Relationship Between End-Tidal Carbon Dioxide and CPR Quality During Both In-Hospital and Out-of-Hospital Cardiac Arrest
The Journal of Emergency Medicine, Vol. 49, No. 2, pp. 254–260, 2015 Copyright Ó 2015 Elsevier Inc. Printed in the USA. All rights reserved 0736-4679/$ - see front matter
Abstracts , QUANTITATIVE RELATIONSHIP BETWEEN END-TIDAL CARBON DIOXIDE AND CPR QUALITY DURING BOTH IN-HOSPITAL AND OUT-OFHOSPITAL CARDIAC ARREST. Sheak KR, Wiebe DJ, Leary M, et al. Resuscitation 2015;89:149 54. The relationship between cardiopulmonary resuscitation (CPR) performance and actual CPR-generated blood flow is not well understood. This study analyzes end tidal CO2 (ETCO2) as an indicator for the quality of CPR. This prospective, cohort study collected both prehospital and in-hospital CPR-recording defibrillator data from multiple medical centers. Chest compression (CC) data, ventilation rate, and ETCO2 values were used from recordings >2 min. Data from 15-s intervals were averaged into ‘‘epochs’’ and analyzed using regression analysis. Of the 790 cardiac arrest events, 583 met inclusion criteria, creating 29,028 epochs of CC and ETCO2 data. In-hospital cardiac arrest (IHCA) events represented 227 (39%) of the included cases, while 356 (61%) were identified as out-of-hospital cardiac arrest (OHCA) events. After analysis of the data, CC depth was found to correlate with increased ETCO2 values, independent of CC rate and ventilation rate. For every 10-mm increase in CC depth, there was an average increase in ETCO2 of 1.4 mm Hg (p < 0.001). In addition, for every additional 10 breaths per minute (bpm) increase in ventilation rate, ETCO2 was lowered by approximately 3.0 mm Hg (p < 0.001), showing the inverse relationship between ventilation rate and ETCO2. There were no significant differences found in IHCA vs. OHCA, nor between shockable or nonshockable rhythms. While there were no associations found between CC rate and depth and patients obtaining return of spontaneous circulation (ROSC) or survival to hospital discharge, there was a significant association in those with ROSC (p < 0.001) and survival to hospital discharge (p < 0.001) with higher ETCO2 values during cardiac arrest. While there are many factors that may affect ETCO2 values during cardiac arrest, this study found a direct relationship between CC depth and ETCO2, as well as a statistically significant increase in rates of ROSC and hospital survival with higher ETCO2 rates during cardiac arrest. This suggests the importance of ETCO2 measurements in cardiac arrest events and the possibility to predict positive outcomes and survival. [Monique Lloyd, MD Denver Health Medical Center, Denver, CO]
, CHEST COMPRESSION RATES AND SURVIVAL FOLLOWING OUT-OF-HOSPITAL CARDIAC ARREST. Idris AH, Guffey D, Pepe PE, et al. Crit Care Med 2015;43:840 8. The goal of this study was to determine the association between chest compression rate during cardiopulmonary resuscitation (CPR) in out of hospital cardiac arrest (OHCA) and return of spontaneous circulation (ROSC) and survival to hospital discharge. This was a prospective observational study from the recent North American Randomized Multicenter Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation Impedance Threshold Device and Early versus Delayed Analysis (PRIMED) trial. In adult OHCA patients with recorded electronic monitor defibrillation, chest compression rates were measured for the first 5 min of CPR. The primary outcome was survival to hospital discharge. The secondary outcomes included ROSC and favorable neurologic survival through a modified Rankin score. Date were obtained on 6399 OHCA patients. Survival was 9% with compression rates of <80/min, 8% for rates between 80 and 100/min, 10% for rates between 100 and 120/min, 8% for rates between 120 and 140/min, and 6% for rates >140/min. After adjusting for sex, age, witnessed arrest, bystander CPR, arrest location, initial rhythm, and study site, there was no significant relationship between compression rate and survival (p = 0.19). However, after adjustment for chest compression depth and fraction, a significant relationship was found between compression rates of 100 to 120/min with survival to hospital discharge (p = 0.02). This study demonstrates the importance of chest compression rate and depth during CPR in cardiac arrest and its potential impact on survival to hospital discharge in OHCA. [Monique Lloyd, MD Denver Health Medical Center, Denver, CO] Comment: This study uses observational data to verify the importance of quality CPR in OHCA patients. While there are many confounding variables that could affect outcomes and survival, it does suggest the importance of chest compression rate and depth in OHCA, and this information is particularly valuable for Emergency Medical Service provider training.
254
The Journal of Emergency Medicine Comment: This study emphasizes the importance and usefulness of ETCO2 in cardiac arrest resuscitation. It also identifies opportunities for future research on the use of ETCO2 in resuscitation efforts. , COMPARATIVE EFFECTIVENESS OF DIAGNOSTIC TESTING STRATEGIES IN EMERGENCY DEPARTMENT PATIENTS WITH CHEST PAIN AN ANALYSIS OF DOWNSTREAM TESTING, INTERVENTIONS, AND OUTCOMES. Foy AJ, Guodong L, Davidson WR, et al. JAMA Intern Med 2015;175:428 36. Chest pain is a common chief complaint from patients presenting to the emergency department (ED), with associated testing costing the US economy $10 to 12 billion per year. This study attempts to compare the association between initial testing strategy and downstream cardiac events. This is a retrospective, cohort study of health insurance claims data from a sample of privately insured patients who received either a primary or secondary diagnosis of chest pain while in the ED. These patients were classified into one of five testing strategies: no noninvasive testing, exercise electrocardiography, stress echocardiography, myocardial perfusion scintigraphy, or coronary computed tomography angiography. Rates of patients requiring cardiac catheterization, coronary revascularization procedure, further noninvasive testing, or hospitalization for myocardial infarction (MI) were measured at 7 and 190 days. A total of 421,774 patients presented with chest pain in studied year and met inclusion criteria. Of these patients, 127,986 received some type of noninvasive testing. Of all patients involved, 464 (0.11%) and 1396 (0.33%) were hospitalized for an acute MI in the following 7 and 190 days, respectively, and there was no statistically significant difference in MI hospitalizations between the different testing groups, including those receiving no initial testing. However, in those groups receiving initial noninvasive testing, there were higher rates of cardiac catheterization and revascularization procedures within the next 7 days without significant difference between the imaging modalities. This study suggests that in patients presenting to the ED with chest pain, the decision for noninvasive testing is not predictive of future occurrence of an MI, suggesting delay of testing to be a reasonable approach. However, it does show that those who receive noninvasive testing are more likely to receive future invasive testing, demonstrating the need for more dedicated research to clarify the best testing for low-risk chest pain patients in the ED. [Monique Lloyd, MD Denver Health Medical Center, Denver, CO] Comment: This study attempts to show there is no difference in hospitalizations for MI, regardless of decision for noninvasive testing for chest pain in the ED. However it is a retrospective study of low-risk privately insured patients. Further prospective studies with a diverse patient population with chest pain need to be conducted before changes in practice are made.
255 , LACTATE MEASUREMENTS IN SEPSIS-INDUCED TISSUE HYPOPERFUSION: RESULTS FROM THE SURVIVING SEPSIS CAMPAIGN DATABASE. Casserly B, Phillips GS, Schorr C, et al. Crit Care Med 2015;43:567 73. One element of the Surviving Sepsis Campaign (SSC) bundle includes measuring serum venous lactate in adult patients with severe sepsis or septic shock. The true relationship between lactate and in-hospital mortality associated with sepsis, however, is not well defined. This study aimed to further delineate the role of lactate measurements as a risk assessment in the SSC resuscitation bundle. The group utilized the SSC database to analyze 19,945 of a total 28,150 enrolled patients who had lactate levels obtained within 6 h of identification of severe sepsis and septic shock, as outlined according to the SCC guidelines. The presence or absence of hypotension was additionally noted as a marker of clinical outcomes. Data were characterized according to the groups: lactate within 6 h > 4 mmol/L (yes/no) and hypotension present (yes/no). Patients who presented with a lactate > 4 mmol/L measured in < 6 h with hypotension (defined as a systolic blood pressure < 90 mm Hg), a mean arterial pressure < 65 mm Hg, or a decrease of $ 40 mm Hg from a known baseline blood pressure, demonstrated a morality of 44.5% vs. 29% compared to the other 3 groups (p < 0.001). Analysis performed on all 23,731 patients in the SSC database with lactates drawn irrespective of the 6-h mark demonstrated that the strongest association existed between elevated lactate and in-hospital mortality in hypotensive patients whose lactates were drawn past 6 h (odds ratio [OR] = 1.26; 95% confidence interval [CI] 1.21 1.32) compared with nonhypotensive patients with lactates drawn within the 6-h mark (OR = 1.07; 95% CI 1.03 1.11). In-hospital mortality rates of patients with lactates obtained at # 6 h were 44.5% vs. 23.1% (OR = 2.10; 95% CI 1.93 2.27) in patients presenting with lactate > 4 mmol/L with hypotension compared to lactate # 2 mmol/L without hypotension. Rates with respect to lactates obtained > 6 h were increased in all groups. Most notably, hypotensive patients presenting with lactate > 4 mmol/L vs. nonhypotensive patients with lactate # 2 mmol/L had mortality rates of 58.6% compared with 29.5% (OR = 3.42; 95% CI 2.87 4.02). The authors conclude that elevated lactate levels are associated with increased in-hospital mortality, but that special attention should be paid to hypotensive patients presenting with lactate > 4 mmol/L in the setting of sepsis, given their significantly increased risk of in-hospital mortality. [Christa Brink Kahn, MD Denver Health Medical Center, Denver, CO] Comment: As clinicians, we are aware of the dangers posed by sepsis and the dramatic clinical courses patients who present with sepsis can take. This study reinforces sepsis as a potentially lethal process and provides strong evidence for the use of lactate measurements with respect to specific parameters as a surrogate
Abstracts , QUANTITATIVE RELATIONSHIP BETWEEN END-TIDAL CARBON DIOXIDE AND CPR QUALITY DURING BOTH IN-HOSPITAL AND OUT-OFHOSPITAL CARDIAC ARREST. Sheak KR, Wiebe DJ, Leary M, et al. Resuscitation 2015;89:149 54. The relationship between cardiopulmonary resuscitation (CPR) performance and actual CPR-generated blood flow is not well understood. This study analyzes end tidal CO2 (ETCO2) as an indicator for the quality of CPR. This prospective, cohort study collected both prehospital and in-hospital CPR-recording defibrillator data from multiple medical centers. Chest compression (CC) data, ventilation rate, and ETCO2 values were used from recordings >2 min. Data from 15-s intervals were averaged into ‘‘epochs’’ and analyzed using regression analysis. Of the 790 cardiac arrest events, 583 met inclusion criteria, creating 29,028 epochs of CC and ETCO2 data. In-hospital cardiac arrest (IHCA) events represented 227 (39%) of the included cases, while 356 (61%) were identified as out-of-hospital cardiac arrest (OHCA) events. After analysis of the data, CC depth was found to correlate with increased ETCO2 values, independent of CC rate and ventilation rate. For every 10-mm increase in CC depth, there was an average increase in ETCO2 of 1.4 mm Hg (p < 0.001). In addition, for every additional 10 breaths per minute (bpm) increase in ventilation rate, ETCO2 was lowered by approximately 3.0 mm Hg (p < 0.001), showing the inverse relationship between ventilation rate and ETCO2. There were no significant differences found in IHCA vs. OHCA, nor between shockable or nonshockable rhythms. While there were no associations found between CC rate and depth and patients obtaining return of spontaneous circulation (ROSC) or survival to hospital discharge, there was a significant association in those with ROSC (p < 0.001) and survival to hospital discharge (p < 0.001) with higher ETCO2 values during cardiac arrest. While there are many factors that may affect ETCO2 values during cardiac arrest, this study found a direct relationship between CC depth and ETCO2, as well as a statistically significant increase in rates of ROSC and hospital survival with higher ETCO2 rates during cardiac arrest. This suggests the importance of ETCO2 measurements in cardiac arrest events and the possibility to predict positive outcomes and survival. [Monique Lloyd, MD Denver Health Medical Center, Denver, CO]
, CHEST COMPRESSION RATES AND SURVIVAL FOLLOWING OUT-OF-HOSPITAL CARDIAC ARREST. Idris AH, Guffey D, Pepe PE, et al. Crit Care Med 2015;43:840 8. The goal of this study was to determine the association between chest compression rate during cardiopulmonary resuscitation (CPR) in out of hospital cardiac arrest (OHCA) and return of spontaneous circulation (ROSC) and survival to hospital discharge. This was a prospective observational study from the recent North American Randomized Multicenter Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation Impedance Threshold Device and Early versus Delayed Analysis (PRIMED) trial. In adult OHCA patients with recorded electronic monitor defibrillation, chest compression rates were measured for the first 5 min of CPR. The primary outcome was survival to hospital discharge. The secondary outcomes included ROSC and favorable neurologic survival through a modified Rankin score. Date were obtained on 6399 OHCA patients. Survival was 9% with compression rates of <80/min, 8% for rates between 80 and 100/min, 10% for rates between 100 and 120/min, 8% for rates between 120 and 140/min, and 6% for rates >140/min. After adjusting for sex, age, witnessed arrest, bystander CPR, arrest location, initial rhythm, and study site, there was no significant relationship between compression rate and survival (p = 0.19). However, after adjustment for chest compression depth and fraction, a significant relationship was found between compression rates of 100 to 120/min with survival to hospital discharge (p = 0.02). This study demonstrates the importance of chest compression rate and depth during CPR in cardiac arrest and its potential impact on survival to hospital discharge in OHCA. [Monique Lloyd, MD Denver Health Medical Center, Denver, CO] Comment: This study uses observational data to verify the importance of quality CPR in OHCA patients. While there are many confounding variables that could affect outcomes and survival, it does suggest the importance of chest compression rate and depth in OHCA, and this information is particularly valuable for Emergency Medical Service provider training.
254
The Journal of Emergency Medicine Comment: This study emphasizes the importance and usefulness of ETCO2 in cardiac arrest resuscitation. It also identifies opportunities for future research on the use of ETCO2 in resuscitation efforts. , COMPARATIVE EFFECTIVENESS OF DIAGNOSTIC TESTING STRATEGIES IN EMERGENCY DEPARTMENT PATIENTS WITH CHEST PAIN AN ANALYSIS OF DOWNSTREAM TESTING, INTERVENTIONS, AND OUTCOMES. Foy AJ, Guodong L, Davidson WR, et al. JAMA Intern Med 2015;175:428 36. Chest pain is a common chief complaint from patients presenting to the emergency department (ED), with associated testing costing the US economy $10 to 12 billion per year. This study attempts to compare the association between initial testing strategy and downstream cardiac events. This is a retrospective, cohort study of health insurance claims data from a sample of privately insured patients who received either a primary or secondary diagnosis of chest pain while in the ED. These patients were classified into one of five testing strategies: no noninvasive testing, exercise electrocardiography, stress echocardiography, myocardial perfusion scintigraphy, or coronary computed tomography angiography. Rates of patients requiring cardiac catheterization, coronary revascularization procedure, further noninvasive testing, or hospitalization for myocardial infarction (MI) were measured at 7 and 190 days. A total of 421,774 patients presented with chest pain in studied year and met inclusion criteria. Of these patients, 127,986 received some type of noninvasive testing. Of all patients involved, 464 (0.11%) and 1396 (0.33%) were hospitalized for an acute MI in the following 7 and 190 days, respectively, and there was no statistically significant difference in MI hospitalizations between the different testing groups, including those receiving no initial testing. However, in those groups receiving initial noninvasive testing, there were higher rates of cardiac catheterization and revascularization procedures within the next 7 days without significant difference between the imaging modalities. This study suggests that in patients presenting to the ED with chest pain, the decision for noninvasive testing is not predictive of future occurrence of an MI, suggesting delay of testing to be a reasonable approach. However, it does show that those who receive noninvasive testing are more likely to receive future invasive testing, demonstrating the need for more dedicated research to clarify the best testing for low-risk chest pain patients in the ED. [Monique Lloyd, MD Denver Health Medical Center, Denver, CO] Comment: This study attempts to show there is no difference in hospitalizations for MI, regardless of decision for noninvasive testing for chest pain in the ED. However it is a retrospective study of low-risk privately insured patients. Further prospective studies with a diverse patient population with chest pain need to be conducted before changes in practice are made.
255 , LACTATE MEASUREMENTS IN SEPSIS-INDUCED TISSUE HYPOPERFUSION: RESULTS FROM THE SURVIVING SEPSIS CAMPAIGN DATABASE. Casserly B, Phillips GS, Schorr C, et al. Crit Care Med 2015;43:567 73. One element of the Surviving Sepsis Campaign (SSC) bundle includes measuring serum venous lactate in adult patients with severe sepsis or septic shock. The true relationship between lactate and in-hospital mortality associated with sepsis, however, is not well defined. This study aimed to further delineate the role of lactate measurements as a risk assessment in the SSC resuscitation bundle. The group utilized the SSC database to analyze 19,945 of a total 28,150 enrolled patients who had lactate levels obtained within 6 h of identification of severe sepsis and septic shock, as outlined according to the SCC guidelines. The presence or absence of hypotension was additionally noted as a marker of clinical outcomes. Data were characterized according to the groups: lactate within 6 h > 4 mmol/L (yes/no) and hypotension present (yes/no). Patients who presented with a lactate > 4 mmol/L measured in < 6 h with hypotension (defined as a systolic blood pressure < 90 mm Hg), a mean arterial pressure < 65 mm Hg, or a decrease of $ 40 mm Hg from a known baseline blood pressure, demonstrated a morality of 44.5% vs. 29% compared to the other 3 groups (p < 0.001). Analysis performed on all 23,731 patients in the SSC database with lactates drawn irrespective of the 6-h mark demonstrated that the strongest association existed between elevated lactate and in-hospital mortality in hypotensive patients whose lactates were drawn past 6 h (odds ratio [OR] = 1.26; 95% confidence interval [CI] 1.21 1.32) compared with nonhypotensive patients with lactates drawn within the 6-h mark (OR = 1.07; 95% CI 1.03 1.11). In-hospital mortality rates of patients with lactates obtained at # 6 h were 44.5% vs. 23.1% (OR = 2.10; 95% CI 1.93 2.27) in patients presenting with lactate > 4 mmol/L with hypotension compared to lactate # 2 mmol/L without hypotension. Rates with respect to lactates obtained > 6 h were increased in all groups. Most notably, hypotensive patients presenting with lactate > 4 mmol/L vs. nonhypotensive patients with lactate # 2 mmol/L had mortality rates of 58.6% compared with 29.5% (OR = 3.42; 95% CI 2.87 4.02). The authors conclude that elevated lactate levels are associated with increased in-hospital mortality, but that special attention should be paid to hypotensive patients presenting with lactate > 4 mmol/L in the setting of sepsis, given their significantly increased risk of in-hospital mortality. [Christa Brink Kahn, MD Denver Health Medical Center, Denver, CO] Comment: As clinicians, we are aware of the dangers posed by sepsis and the dramatic clinical courses patients who present with sepsis can take. This study reinforces sepsis as a potentially lethal process and provides strong evidence for the use of lactate measurements with respect to specific parameters as a surrogate