Maria Margarita Gonzalez

Left Ventricular Systolic Function and Outcome After In-Hospital Cardiac Arrest

Background— The effect of prearrest left ventricular ejection fraction (LVEF) on outcome after cardiac arrest is unknown. Methods and Results— During a 26-month period, Utstein-style data were prospectively collected on 800 consecutive inpatient adult index cardiac arrests in an observational, single-center study at a tertiary cardiac care hospital. Prearrest echocardiograms were performed on 613 patients (77%) at 11±14 days before the cardiac arrest. Outcomes among patients with normal or nearly normal prearrest LVEF (≥45%) were compared with those of patients with moderate or severe dysfunction (LVEF <45%) by &khgr;2 and logistic regression analyses. Survival to discharge was 19% in patients with normal or nearly normal LVEF compared with 8% in those with moderate or severe dysfunction (adjusted odds ratio, 4.8; 95% confidence interval, 2.3 to 9.9; P<0.001) but did not differ with regard to sustained return of spontaneous circulation (59% versus 56%; P=0.468) or 24-hour survival (39% versus 36%; P=0.550). Postarrest echocardiograms were performed on 84 patients within 72 hours after the index cardiac arrest; the LVEF decreased 25% in those with normal or nearly normal prearrest LVEF (60±9% to 45±14%; P<0.001) and decreased 26% in those with moderate or severe dysfunction (31±7% to 23±6%, P<0.001). For all patients, prearrest &bgr;-blocker treatment was associated with higher survival to discharge (33% versus 8%; adjusted odds ratio, 3.9; 95% confidence interval, 1.8 to 8.2; P<0.001). Conclusions— Moderate and severe prearrest left ventricular systolic dysfunction was associated with substantially lower rates of survival to hospital discharge compared with normal or nearly normal function.

Aliança Internacional dos Comitês de Ressuscitação (ILCOR): papel nas novas diretrizes de ressuscitação cardiopulmonar e cuidados cardiovasculares de emergência 2005-2010

Resuscitation, sudden cardiac, emergency cardiovascular care.in January 2005. The proceedings of this meeting provided material for regional consensus organizations to write their own resuscitation guidelines.The creation of ILCOR established a unique opportunity for international collaboration in the development of guidelines and training programs on resuscitation over the past fifteen years. A short summary of the important aspects and the progress of the organization, which has become the authoritative voice on the scientific consensus behind national and international resuscitation guidelines, is presented below.

Survival After Ventricular Fibrillation Cardiac Arrest in the Sao Paulo Metropolitan Subway System: First Successful Targeted Automated External Defibrillator (AED) Program in Latin America.

Background Targeted automated external defibrillator (AED) programs have improved survival rates among patients who have an out‐of‐hospital cardiac arrest (OHCA) in US airports, as well as European and Japanese railways. The Sao Paulo (Brazil) Metro subway carries 4.5 million people per day. A targeted AED program was begun in the Sao Paulo Metro with the objective to improve survival from cardiac arrest. Methods and Results A prospective, longitudinal, observational study of all cardiac arrests in the Sao Paulo Metro was performed from September 2006 through November 2012. This study focused on cardiac arrest by ventricular arrhythmias, and the primary endpoint was survival to hospital discharge with minimal neurological impairment. A total of 62 patients had an initial cardiac rhythm of ventricular fibrillation. Because no data on cardiac arrest treatment or outcomes existed before beginning this project, the first 16 months of the implementation was used as the initial experience and compared with the subsequent 5 years of full operation. Return of spontaneous circulation was not different between the initial 16 months and the subsequent 5 years (6 of 8 [75%] vs. 39 of 54 [72%]; P=0.88). However, survival to discharge was significantly different once the full program was instituted (0 of 8 vs. 23 of 54 [43%]; P=0.001). Conclusions Implementation of a targeted AED program in the Sao Paulo Metro subway system saved lives. A short interval between arrest and defibrillation was key for good long‐term, neurologically intact survival. These results support strategic expansion of targeted AED programs in other large Latin American cities.

Myocardial protection induced by fentanyl in pigs exposed to high-dose adrenaline

The use of high doses of adrenaline is common in critical patients, especially during cardiac arrest. During these situations, myocardial dysfunction can be a result of multiple factors, including adrenaline use. In addition, opioids have been shown to have anti‐arrhythmic and anti‐ischemic mechanisms that may confer cardiac protection. This study aimed to evaluate the effects of fentanyl on myocardial function in pigs exposed to high‐dose adrenaline. After institutional ethics committee approval, 26 pigs were randomly allocated to receive either 20 μg/kg fentanyl (n = 10; fentanyl group) administered 5 min before five doses of adrenaline (20 μg/kg), equivalent‐volume saline (n = 10; saline group) using the same adrenaline dosing protocol, or neither fentanyl nor adrenaline (n = 6; sham group). The fentanyl group showed lower levels of troponin at the end of the sixth hour compared with the saline group (1.91 ± 1.47 vs 5.44 ± 5.35 ng/mL, P = 0.019). Transmission electron microscopy and immunohistochemistry also showed less myocardial injury in the fentanyl group. The conclusion was reached that fentanyl attenuates myocardial injury caused by high‐dose adrenaline without blunting the hemodynamic effect of adrenaline.

Outcomes of patients with trauma and intraoperative cardiac arrest

BACKGROUND Although the occurrence of intraoperative cardiac arrest is rare, it is a severe adverse event with a high mortality rate. Trauma patients have additional causes for intraoperative arrest, and we hypothesised that the survival of trauma patients who experienced intraoperative cardiac arrest would be worse than nontrauma patients who experienced intraoperative cardiac arrest. OBJECTIVES The aim of the present study was to compare the outcomes of trauma and nontrauma patients after intraoperative cardiac arrest. METHODS In a tertiary university hospital and trauma centre, the intraoperative cardiac arrest cases were evaluated from January 2007 to December 2009, excluding patients submitted to cardiac surgery. Data were prospectively collected using the Utstein-style. Outcomes among the patients with trauma were compared to the patients without trauma. RESULTS We collected data from 81 consecutive intraoperative cardiac arrest cases: 32 with trauma and 49 without trauma. Patients in the trauma group were younger than the patients in the nontrauma group (44±23 vs. 63±17, p<0.001). Hypovolaemia (63% vs. 35%, p=0.022) and metabolic/hydroelectrolytic disturbances (41% vs. 2%, p<0.001) were more likely to cause the cardiac arrest in the trauma group. The first documented arrest rhythm did not differ between the groups, and pulseless electrical activity was the most prevalent rhythm (66% vs. 53%, p=0.698). The return of spontaneous circulation (47% vs. 63%, p=0.146) and survival to discharge with favourable neurological outcome (16% vs. 14%, p=0.869) did not differ between the two groups. CONCLUSIONS The outcomes did not differ between patients with trauma and nontrauma intraoperative cardiac arrest.

Quality of continuous chest compressions performed for one or two minutes

OBJECTIVES: This study was designed to assess cardiopulmonary resuscitation quality and rescuer fatigue when rescuers perform one or two minutes of continuous chest compressions. METHODS: This prospective crossover study included 148 lay rescuers who were continuously trained in a cardiopulmonary resuscitation course. The subjects underwent a 120-min training program comprising continuous chest compressions. After the course, half of the volunteers performed one minute of continuous chest compressions, and the others performed two minutes, both on a manikin model. After 30 minutes, the volunteers who had previously performed one minute now performed two minutes on the same manikin and vice versa. RESULTS: A comparison of continuous chest compressions performed for one and two minutes, respectively, showed that there were significant differences in the average rate of compressions per minute (121 vs. 124), the percentage of compressions of appropriate depth (76% vs. 54%), the average depth (53 vs. 47 mm), and the number of compressions with no errors (62 vs. 47%). No parameters were significantly different when comparing participants who performed regular physical activity with those who did not and participants who had a normal body mass index with overweight/obese participants. CONCLUSION: The quality of continuous chest compressions by lay rescuers is superior when it is performed for one minute rather than for two minutes, independent of the body mass index or regular physical activity, even if they are continuously trained in cardiopulmonary resuscitation. It is beneficial to rotate rescuers every minute when performing continuous chest compressions to provide higher quality and to achieve greater success in assisting a victim of cardiac arrest.

Frequency of intraoperative cardiac arrest and medium-term survival

CONTEXT AND OBJECTIVE Although advances in surgical and anesthetic techniques have reduced perioperative morbidity-mortality, the survival rate following cardiac arrest remains low. The aim of this study was to evaluate, over the course of one year, the prevalence of intraoperative cardiac arrest and the 30-day survival rate after this event in a tertiary teaching hospital. DESIGN AND SETTING Prospective cohort study in a tertiary teaching hospital. METHODS Following approval by the institutional ethics committee, anesthetic procedures and cases of intraoperative cardiac arrest between January and December 2007 were evaluated. Patients undergoing cardiac surgery were excluded. The data were gathered prospectively using the modified Utstein model, with evaluation of demographic data, pre-arrest conditions, intraoperative care, care during arrest and postoperative outcome up to the 30th day. The data were recorded by the attending anesthesiologist. RESULTS During the study period, 40,379 anesthetic procedures were performed, and 52 cases of intraoperative cardiac arrest occurred (frequency of 13:10,000). Among these, 69% presented spontaneous return of circulation after the initial arrest, and only 25% survived for 30 days after the event. The following factors were associated with shorter survival: American Society of Anesthesiologists physical status IV and V, emergency surgery, hemorrhagic events, hypovolemia as the cause of arrest and use of atropine during resuscitation. CONCLUSIONS Although the frequency of cardiac arrest in the surgical environment has declined and resources to attend to this exist, the survival rate is low. Factors associated with worst prognosis are more frequent in critical patients.

Perioperative cardiac arrest: an evolutionary analysis of the intra-operative cardiac arrest incidence in tertiary centers in Brazil

BACKGROUND Great changes in medicine have taken place over the last 25 years worldwide. These changes in technologies, patient risks, patient profile, and laws regulating the medicine have impacted the incidence of cardiac arrest. It has been postulated that the incidence of intraoperative cardiac arrest has decreased over the years, especially in developed countries. The authors hypothesized that, as in the rest of the world, the incidence of intraoperative cardiac arrest is decreasing in Brazil, a developing country. OBJECTIVES The aim of this study was to search the literature to evaluate the publications that relate the incidence of intraoperative cardiac arrest in Brazil and analyze the trend in the incidence of intraoperative cardiac arrest. CONTENTS There were 4 articles that met our inclusion criteria, resulting in 204,072 patients undergoing regional or general anesthesia in two tertiary and academic hospitals, totalizing 627 cases of intraoperative cardiac arrest. The mean intraoperative cardiac arrest incidence for the 25 years period was 30.72:10,000 anesthesias. There was a decrease from 39:10,000 anesthesias to 13:10,000 anesthesias in the analyzed period, with the related lethality from 48.3% to 30.8%. Also, the main causes of anesthesia-related cause of mortality changed from machine malfunction and drug overdose to hypovolemia and respiratory causes. CONCLUSIONS There was a clear reduction in the incidence of intraoperative cardiac arrest in the last 25 years in Brazil. This reduction is seen worldwide and might be a result of multiple factors, including new laws regulating the medicine in Brazil, incorporation of technologies, better human development level of the country, and better patient care.

Fatores biológicos e superestimação da fração de ejeção do ventrículo esquerdo no gated SPECT

BACKGROUND Some patients present an overestimated left ventricular ejection fraction (LVEF) on electrocardiogram-gated myocardial scintigraphy (gated SPECT). OBJECTIVE To establish the relationship between biological factors and overestimated LVEF. METHODS We selected 3838 patients who underwent gated SPECT between May 20, 2000 and September 16, 2005 with normal perfusion images and LVEF > or =50%. The following variables were analyzed: gender (29.4% females and 70.6% males), age (from 20 to 94 years - mean: 56 years), weight (from 33.5 to 150 kg - mean: 79.6 kg), height (from 138 to 220 cm - mean: 171 cm) and BMI (from 13.9 to 54 - mean: 27.2). In a subgroup of 1002 patients who underwent echocardiogram, the diastolic diameter (from 36 to 68 mm - mean 47.5 mm) and systolic diameter (from 22 to 41 mm - mean 29.8 mm) variables were included. The patients were divided into two groups: normal LVEF (< or =80%) and overestimated LVEF (>80%). The odds ratio (OR) for presenting an overestimated LVEF was calculated for each variable using logistic regression. RESULTS The following odds ratios were found (p < 0.005): female gender OR = 3.585 (95%CI: 2.745 to 4.683), age in years OR = 1.020 (95%CI: 1.011 to 1.029) and height in cm OR = 0.893 (95%CI: 0.829 to 0.962). Weight and BMI were not significantly associated with LVEF (p>0.2). In the subgroup of 1002 patients, a statistically significant influence was found in overestimated LVEF values for the systolic diameter, gender and height variables. CONCLUSION Although systolic diameter influences the overestimation of LVEF, the gender and height variables have an independent influence on LVEF overestimation by gated SPECT.

Prolonged cardiopulmonary arrest treated successfully in the São Paulo's subway.

In Brazil, circulatory diseases, including CPA (Cardiopulmonary Arrests), were the leading cause of death in 20101. Estimates are that, in Brazil, around 220,000 CPAs happen every year, including ventricular fibrillation, 180,000 in pre-hospital environment and 40,000 in-hospital2. Recent observational studies of victims of CPA in extra-hospital environment revealed that only CCC (Continuous Chest Compressions) - hands-only CPR - were equivalent or higher than conventional CPR (Cardiopulmonary Resuscitation) (using a 30:2 ratio of compressions/ventilations) in adult patients, mainly with regard to neurological benefits3-5. We present a case of PCA occurred in Companhia do Metropolitano de Sao Paulo (Sao Paulos Subway) attended by lay rescuers who performed CCC and applied shocks by means of AED (Automatic External Defibrillator).