Sex Differences in Chronic Thromboembolic Pulmonary Hypertension. Treatment Options over Time in a National Referral Center.

(1) Background: Clinical presentation, disease distribution, or treatment received may provide insights into the reasons contributing to sex differences in chronic thromboembolic pulmonary hypertension (CTEPH). (2) Methods: We evaluated 453 patients (56% women) between 2007-2019. Data was collected from REHAP (Registro Español de Hipertensión Arterial Pulmonar) registry. Two time periods were selected to evaluate the influence of new treatments over time. (3) Results: Women were older. Baseline functional class was worse, and distance walked shorter in women compared with men. Women had higher pulmonary vascular resistances. Despite this, pulmonary endarterectomy (PEA) was carried out in more men, and women received more frequently pulmonary vasodilators exclusively. The 2014-2019 interval was associated with a better survival only among women. Interestingly, women had a more distal disease during this second period of time. (4) Conclusions: Even though women were older, and received invasive treatments less frequently, mortality was similar in both sexes. The introduction of balloon pulmonary angioplasty and the improvement of pulmonary endarterectomy, especially during the last years, could be associated with a survival benefit among women.

Eradication of Staphylococcus aureus Post-Sternotomy Mediastinitis Following the Implementation of Universal Preoperative Nasal Decontamination With Mupirocin: An Interrupted Time-Series Analysis.

BACKGROUND: Although presurgical nasal decontamination with mupirocin (NDM) has been advocated as a measure for preventing postsurgical mediastinitis (PSM) due to Staphylococcus aureus, this strategy is not universally recommended due to lack of robust supporting evidence. We aimed to evaluate the role of preoperative NDM in the annual incidence of S. aureus PSM at our institution. METHODS: An interrupted time-series analysis, with an autoregressive error model, was applied to our single-center cohort by comparing preintervention (1990-2003) and postintervention (2005-2018) periods. Logistic regression was performed to analyze risk factors for S. aureus PSM. RESULTS: 12 236 sternotomy procedures were analyzed (6370 [52.1%] and 5866 [47.9%] in the pre- and postintervention periods, respectively). The mean annual percentage adherence to NDM estimated over the postintervention period was 90.2%. Only 4 of 127 total cases of S. aureus PSM occurred during the 14-year postintervention period (0.68/1000 sternotomies vs 19.31/1000 in the preintervention period; P < .0001). Interrupted time-series analysis demonstrated a statistically significant annual reduction in S. aureus PSM of -9.85 cases per 1000 sternotomies (-13.17 to -6.5; P < .0001) in 2005, with a decreasing trend maintained over the following 5 years and an estimated relative reduction of 84.8% (95% confidence interval [CI], 89.25-74.09%). Chronic obstructive pulmonary disease was the single independent risk factor for S. aureus PSM (odds ratio, 3.7; 95% CI, 1.72-7.93) and was equally distributed in patients undergoing sternotomy during pre- or postintervention periods. CONCLUSIONS: Our experience suggests the implementation of preoperative NDM significantly reduces the incidence of S. aureus PSM.

Feasibility of a Noninvasive Operability Assessment in Chronic Thromboembolic Pulmonary Hypertension under Real-World Practice.

This study aimed to evaluate the feasibility of a noninvasive operability assessment of chronic thromboembolic pulmonary hypertension (CTEPH) based on multidetector computed tomographic angiography (MCTA). Up to 176 patients were evaluated from January 2016 to April 2018. Throughout the first phase, the initial surgical decision was made based on MCTA with further analysis of pulmonary angiography (PA) in order to evaluate in which cases the initial decision was not modified by PA. During the second phase, PA was limited to patients judged inoperable based on MCTA or those whose assessment was not possible. Patients deemed operable (50%) based on MCTA along the first phase had been adequately classified, as PA did not modify the initial decision in all but one patient. Comparable results were obtained throughout the implementation phase. Regarding operated patients, the decision of operability was based solely on MCTA in 94% of those with level I disease, in 75% with level II, and 54% with level III. This approach enabled shorter periods of time to complete surgical assessment and the avoidance of PA-related morbidity. Baseline parameters, postoperative measures, and survival rates at 1 year after surgery were comparable in both phases. Noninvasive operability assessment is feasible in a subset of CTEPH patients and optimizes surgical candidacy evaluation.

Awake ECMO-VA en shock cardiogénico: una experiencia prometedora / Awake VA-ECMO in cardiogenic shock: an experience with future potential

No disponible

Soporte circulatorio con oxigenador extracorpóreo de membrana durante el embarazo en la enfermedad venooclusiva pulmonar / Extracorporeal membrane oxygenation support during pregnancy in pulmonary veno-occlusive disease

No disponible

Incidence, Risk Factors and Outcomes of Early Acute Kidney Injury After Heart Transplantation: An 18-year Experience.

BACKGROUND: Little is known about the incidence of acute kidney injury (AKI), as defined using the Kidney Disease Improving Global Outcome classification, after heart transplantation (HT). Our objective was to evaluate the impact of AKI in a cohort of HT recipients. (Setting: University Hospital.) METHODS: We studied 310 consecutive HT recipients from 1999 to 2017, with AKI being defined according to the Kidney Disease Improving Global Outcome criteria. Risk factors were analyzed by multivariable analyses, and survival by Kaplan-Meier curves and a risk-adjusted Cox proportional hazards regression model. RESULTS: One hundred twenty-five (40.3%) patients developed AKI, with 73 (23.5%), 18 (5.8%), and 34 (11%) patients having AKI stages 1, 2, and 3, respectively. Cardiac tamponade (odds ratio [OR], 16.82; 95% confidence interval [CI], 1.06-138), acute right ventricular failure (OR, 3.54; 95% CI, 1.82-6.88), and major bleeding (OR, 2.46; 95% CI, 1.18-5.1) were the principal risk factors for AKI. Patients with AKI had a greater hospital mortality (3.8% vs 16%, P < 0.05), especially those requiring renal replacement therapy (46.9% vs 5.4%, P = 0.006). Acute kidney injury requiring renal replacement therapy was independently associated with hospital mortality (OR, 11.03; 95% CI, 4.08-29.8). With a median follow-up after hospital discharge of 6.7 years (interquartile range, 2.4-11.6), overall survival at 1, 5, and 10 years was 95.4%, 85.1%, and 75.4% versus 85.2%, 69.8% and 63.5% among patients without AKI and with AKI stages 2 to 3, respectively (P = 0.08). CONCLUSIONS: The onset of AKI after HT is mainly associated with postoperative complications. Only severe AKI stage predicts worse short-term outcome, with this impact appearing to be lost at long-term follow-up.

Resultados de la tromboendarterectomía pulmonar en la hipertensión pulmonar tromboembólica crónica / Pulmonary endarterectomy outputs in chronic thromboembolic pulmonary hypertension

Fundamento y objetivo: La cirugía de tromboendarterectomía pulmonar es el tratamiento de elección para la hipertensión pulmonar tromboembólica crónica; un factor de riesgo para la mortalidad hospitalaria son las resistencias vasculares pulmonares muy elevadas. El objetivo de este trabajo fue analizar los resultados inmediatos y a largo plazo de la cirugía para la hipertensión pulmonar tromboembólica crónica en pacientes con hipertensión pulmonar muy grave. Material y métodos: Desde febrero de 1996 hemos realizado 160 tromboendarterectomías pulmonares. Dividimos esta población en grupo 1 -40 pacientes con resistencias vasculares pulmonares ≥ 1.090dinas/s/cm-5- y grupo 2 -los 120 restantes-. Resultados: La mortalidad hospitalaria (15 frente a 2,5%), el edema pulmonar de reperfusión (33 frente a 14%) y la insuficiencia cardiaca (23 frente a 3,3%) fueron significativamente mayores en el grupo 1; pero al año, no hay diferencia en la situación clínica, hemodinámica y ecocardiográfica con el grupo 2. La supervivencia a los 5 años fue del 77% en el grupo 1 y del 92% en el grupo 2 (p=0,033). Excluyendo los primeros 46 enfermos, considerados curva de aprendizaje, no hubo diferencia en la mortalidad hospitalaria (3,8 frente a 2,3%) ni en la supervivencia (96,2% en el grupo 1 y 96,2% en el grupo 2 a los 5 años). Conclusiones: La tromboendarterectomía pulmonar tiene una morbimortalidad inicial mayor en pacientes con hipertensión pulmonar tromboembólica crónica muy grave, pero obtiene el mismo beneficio a medio-largo plazo. En nuestra experiencia, tras la curva de aprendizaje, la cirugía ofrece la misma seguridad y excelentes resultados a los pacientes más graves, y ninguna cifra de resistencias vasculares pulmonares debería ser considerada una contraindicación absoluta (AU)

Background and objective: Pulmonary thromboendarterectomy surgery is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension; extremely high pulmonary vascular resistance constitutes a risk factor for hospital mortality. The objective of this study was to analyze the immediate and long-term results of the surgical treatment of chronic thromboembolic pulmonary hypertension in patients with very severe pulmonary hypertension. Material and methods: Since February 1996, we performed 160 pulmonary thromboendarterectomies. We divided the patient population in 2 groups: group 1, which included 40 patients with pulmonary vascular resistance≥1090dyn/sec/cm-5, and group 2, which included the remaining 120 patients. Results: Hospital mortality (15 vs. 2.5%), reperfusion pulmonary edema (33 vs. 14%) and heart failure (23 vs. 3.3%) were all higher in group 1; however, after one year of follow-up, there were no significant differences in the clinical, hemodynamic and echocardiographic conditions of both groups. Survival rate after 5 years was 77% in group 1 and 92% in group 2 (P=.033). After the learning curve including the 46 first patients, there was no difference in hospital mortality (3.8 vs. 2.3%) or survival rate after 5 years (96.2% in group 1 and 96.2% in group 2). Conclusions: Pulmonary thromboendarterectomy is linked to significantly higher morbidity and mortality rates in patients with severe chronic thromboembolic pulmonary hypertension. Nevertheless, these patients benefit the same from the procedure in the mid-/long-term. In our experience, after the learning curve, this surgery is safe in severe pulmonary hypertension and no level of pulmonary vascular resistance should be an absolute counter-indication for this surgery (AU)

Pulmonary endarterectomy outputs in chronic thromboembolic pulmonary hypertension. / Resultados de la tromboendarterectomía pulmonar en la hipertensión pulmonar tromboembólica crónica.

BACKGROUND AND OBJECTIVE: Pulmonary thromboendarterectomy surgery is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension; extremely high pulmonary vascular resistance constitutes a risk factor for hospital mortality. The objective of this study was to analyze the immediate and long-term results of the surgical treatment of chronic thromboembolic pulmonary hypertension in patients with very severe pulmonary hypertension. MATERIAL AND METHODS: Since February 1996, we performed 160 pulmonary thromboendarterectomies. We divided the patient population in 2 groups: group 1, which included 40 patients with pulmonary vascular resistance≥1090dyn/sec/cm-5, and group 2, which included the remaining 120 patients. RESULTS: Hospital mortality (15 vs. 2.5%), reperfusion pulmonary edema (33 vs. 14%) and heart failure (23 vs. 3.3%) were all higher in group 1; however, after one year of follow-up, there were no significant differences in the clinical, hemodynamic and echocardiographic conditions of both groups. Survival rate after 5 years was 77% in group 1 and 92% in group 2 (P=.033). After the learning curve including the 46 first patients, there was no difference in hospital mortality (3.8 vs. 2.3%) or survival rate after 5 years (96.2% in group 1 and 96.2% in group 2). CONCLUSIONS: Pulmonary thromboendarterectomy is linked to significantly higher morbidity and mortality rates in patients with severe chronic thromboembolic pulmonary hypertension. Nevertheless, these patients benefit the same from the procedure in the mid-/long-term. In our experience, after the learning curve, this surgery is safe in severe pulmonary hypertension and no level of pulmonary vascular resistance should be an absolute counter-indication for this surgery.

'Jamaican Stone': A potentially lethal remedy for delaying ejaculation.

Poisoning by ingestion of 'Jamaican Stone', a kind of cardioactive steroid, is extremely rare. However, mortality is very high. For this reason, when it occurs, an early and accurate diagnosis represents a critical challenge for clinicians. We present an unusual case of electrical storm caused by this substance.

Evaluation of right ventricular function after cardiac surgery: The importance of tricuspid annular plane systolic excursion and right ventricular ejection fraction.

OBJECTIVE: The evaluation of right ventricular systolic function is essential to the hemodynamic management of critically ill cardiac patients. Nevertheless, assessment of right ventricular function remains problematic. We sought to analyze the correlation between tricuspid annular plane systolic excursion (TAPSE) and right ventricular ejection fraction (RVEF) in the assessment of global and regional right ventricular function, respectively. METHODS: This was a prospective study of 61 cardiac surgical patients. TAPSE was measured with transthoracic echocardiography and RVEF was obtained by a thermodilution pulmonary artery catheter. Both measurements were estimated simultaneously during the early postoperative period. Patients with previously identified severe tricuspid insufficiency were excluded from the study to avoid confounding results. RESULTS: The etiologies for cardiac surgery were surgical pulmonary thromboendarterectomy in 19 patients, valve replacement in 17 patients, heart transplant in 13 patients, and coronary artery bypass graft in 9 patients. Mean RVEF and TAPSE were 26.2% ± 9.7% and 11.4 ± 4 mm, respectively. RVEF and TAPSE showed a significant correlation (r = 0.73, P < .001). Weak reverse relationships between TAPSE or RVEF with afterload hemodynamic parameters, mean pulmonary artery pressure, or pulmonary vascular resistance were elucidated. CONCLUSIONS: TAPSE is a robust measure of right ventricular function that correlates with RVEF assessed by pulmonary artery catheter. A noninvasive method such as echocardiography can guide and support invasive monitoring of right ventricular function in cardiac surgical patients.

Veno-arterial ECMO for rescue of severe airway hemorrhage with rigid bronchoscopy after pulmonary artery thromboendarterectomy.

Pulmonary endarterectomy (PEA) is the treatment of choice to relieve pulmonary artery obstruction in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We present a patient with airway obstruction and acute respiratory failure due to large blood clots obstructing the trachea and main left bronchus. This condition was accompanied by right ventricle failure and cardiogenic shock. A venoarterial ECMO system was used for cardiopulmonary support before extracting the clots and clearing the airway by rigid bronchoscopy.

Tromboendarterectomía pulmonar en 106 pacientes con hipertensión pulmonar tromboembólica crónica / Pulmonary Thromboendarterectomy in 106 Patients With Chronic Thromboembolic Pulmonary Hypertension

Introducción: La tromboendarterectomía pulmonar es el tratamiento de elección en la hipertensión pulmonar tromboembólica crónica. Presentamos nuestra serie completa con esta técnica. Métodos: Desde febrero de 1996 hasta junio de 2014, hemos realizado 106 tromboendarterectomías. Analizamos las características de la población, la mortalidad y morbilidad asociadas a la técnica y los resultados a largo plazo de supervivencia, mejoría funcional y resolución de la hipertensión pulmonar. Resultados: La edad media de la población fue 53 ± 14 años. El 89% estaba en clase funcional III-IV de la OMS. La presión pulmonar media prequirúrgica fue 49 ± 13 mmHg y las resistencias vasculares pulmonares 831 ± 364 dinas.s.cm-5. La mortalidad hospitalaria fue 6,6%. La morbilidad postoperatoria más relevante fue debida al edema pulmonar por reperfusión en el 20%, que fue factor de riesgo independiente (p = 0,015) para mortalidad hospitalaria. Con una mediana de seguimiento de 31 meses (rango intercuartil 50), la supervivencia a los 3 y 5 años es 90 y 84%. Al año de seguimiento, el 91% está en clase funcional I-II de la OMS, la presión pulmonar media en 27 ± 11 mmHg y las resistencias pulmonares vasculares en 275 ± 218 dinas.s.cm-5 (significativamente menores (p < 0,05) que las basales). En 14 pacientes se diagnosticó hipertensión pulmonar persistente; aun así, su supervivencia es, a los 3 y 5 años, 91 y 73%, respectivamente. Conclusiones: La tromboendarterectomía pulmonar ofrece resultados excelentes en el tratamiento de la hipertensión pulmonar tromboembólica crónica. Proporciona una elevada supervivencia a largo plazo, mejora la capacidad funcional y resuelve la hipertensión pulmonar en la mayoría de los pacientes

Introduction: Pulmonary thromboendarterectomy is the treatment of choice in chronic thromboembolic pulmonary hypertension. We report our experience with this technique. Methods: Between February 1996 and June 2014, we performed 106 pulmonary thromboendarterectomies. Patient population, morbidity and mortality and the long-term results of this technique (survival, functional improvement and resolution of pulmonary hypertension) are described. Results: Subjects' mean age was 53 ± 14 years. A total of 89% were WHO functional class III–IV, presurgery mean pulmonary pressure was 49 ± 13 mmHg and mean pulmonary vascular resistance was 831 ± 364 dynes s cm-5. In-hospital mortality was 6.6%. The most important post-operative morbidity was reperfusion pulmonary injury, in 20% of patients; this was an independent risk factor (P = .015) for hospital mortality. With a 31-month median follow-up (interquartile range: 50), 3- and 5-year survival was 90% and 84% respectively. At 1 year, 91% were WHO functional class I–II; mean pulmonary pressure (27 ± 11 mmHg) and pulmonary vascular resistance (275 ± 218 dynes s cm-5) were significantly lower (P < .05) than before the intervention. Although residual pulmonary hypertension was detected in 14 patients, their survival at 3 and 5 years was 91% and 73%, respectively. Conclusions: Pulmonary thromboendarterectomy offers excellent results in chronic thromboembolic pulmonary hypertension. Long-term survival is good, functional capacity improves, and pulmonary hypertension is resolved in most patients

Pulmonary thromboendarterectomy in 106 patients with chronic thromboembolic pulmonary hypertension.

INTRODUCTION: Pulmonary thromboendarterectomy is the treatment of choice in chronic thromboembolic pulmonary hypertension. We report our experience with this technique. METHODS: Between February 1996 and June 2014, we performed 106 pulmonary thromboendarterectomies. Patient population, morbidity and mortality and the long-term results of this technique (survival, functional improvement and resolution of pulmonary hypertension) are described. RESULTS: Subjects' mean age was 53±14 years. A total of 89% were WHO functional class III-IV, presurgery mean pulmonary pressure was 49±13mmHg and mean pulmonary vascular resistance was 831±364 dynes.s.cm(-5). In-hospital mortality was 6.6%. The most important post-operative morbidity was reperfusion pulmonary injury, in 20% of patients; this was an independent risk factor (p=0.015) for hospital mortality. With a 31-month median follow-up (interquartile range: 50), 3- and 5-year survival was 90 and 84%. At 1 year, 91% were WHO functional class I-II; mean pulmonary pressure (27±11mmHg) and pulmonary vascular resistance (275±218 dynes.s.cm(-5)) were significantly lower (p<0.05) than before the intervention. Although residual pulmonary hypertension was detected in 14 patients, their survival at 3 and 5 years was 91 and 73%, respectively. CONCLUSIONS: Pulmonary thromboendarterectomy offers excellent results in chronic thromboembolic pulmonary hypertension. Long-term survival is good, functional capacity improves, and pulmonary hypertension is resolved in most patients.

Early enteral nutrition in patients with hemodynamic failure following cardiac surgery.

BACKGROUND: Enteral nutrition (EN) is controversial in patients with circulatory compromise. This study assesses the feasibility and safety of EN given early after cardiac surgery in patients with hemodynamic failure. METHODS: Prospective observational study conducted in a surgical intensive care unit (ICU) of a tertiary hospital over 17 months. INCLUSION CRITERIA: Cardiac surgery patients with hemodynamic failure (dependence on 2 or more vasoactive drugs and/or mechanical circulatory support) requiring more than 24 hours of mechanical ventilation. Variables Examined: Descriptive data, daily hemodynamic data, and variables related to the efficacy and safety of EN. EN was performed according to our EN protocol. RESULTS: Of 642 patients admitted to the ICU, 37 (5.8%) met the inclusion criteria. Of these, 11 (29.7%) required mechanical circulatory support, and 25 (68.0%) met the criteria for early multiorgan dysfunction. Mortality was 13.5%. Mean EN duration was 12.3 days (95% confidence interval [CI], 9.6-15.0). The mean EN diet volume delivered/patient/d was 1199 mL (95% CI, 1118.7-1278.8), and mean EN energy delivered/patient/d was 1228.4 kcal (95% CI, 1145.8-1311). The set energy target was achieved in 15 patients (40.4%). The most common EN-related complication was constipation. No case of mesenteric ischemia was detected. CONCLUSIONS: Our findings indicate that early EN is feasible in this type of patients and not associated with serious complications. However, it is difficult to attain an appropriate energy target by EN alone. These observations point to a need for monitoring of daily energy delivery and balance, as well as careful monitoring of warning signs of intestinal ischemia.

Early enteral nutrition in adults receiving venoarterial extracorporeal membrane oxygenation: an observational case series.

BACKGROUND: Despite its benefits, early enteral nutrition (EN) is considered controversial in critically ill patients with severe hemodynamic failure. OBJECTIVE: To evaluate the tolerance and safety of early EN in a consecutive group of patients receiving venoarterial (VA) extracorporeal membrane oxygenation (ECMO) for severe hemodynamic failure. MATERIALS AND METHODS: Prospective observational study performed in a cardiac surgical intensive care unit (ICU) during a 1-year period. All adult patients receiving VA ECMO for severe hemodynamic failure unresponsive to conventional therapies were included. Nutrition support was provided during the study period following the established ICU nutrition protocol. Energy target was 25 kcal/kg, to be reached over 4 days. Nutrition tolerance was defined as the ratio of delivered nutrition to target nutrition, expressed as a percentage. Special interest was made to detect possible adverse effects attributable to EN. The authors performed a descriptive statistical analysis. RESULTS: Of 553 patients admitted in the cardiac surgical ICU during the study period, 7 were treated with ECMO. EN was the only nutrition source. More than 70% nutrition tolerance was achieved within the first week in all cases. No serious adverse events that could be attributable to EN were noted. CONCLUSION: The present study shows that, under proper medical supervision, early EN is possible and safe in patients with severe hemodynamic failure receiving VA ECMO. No serious adverse events were attributable to EN. More studies are warranted to confirm these findings.

Insuficiencia ventricular derecha en el seno de la cirugía cardiaca / Right ventricular failure and cardiac surgery

La insuficiencia del ventrículo derecho tras la cirugía cardiaca sigue siendo un problema clínico significativo, especialmente en determinados contextos quirúrgicos: cardiopatías congénitas, enfermedad valvular mitral con hipertensión pulmonar, enfermedad coronaria de alto riesgo, trasplante cardiaco, tromboendarterectomía pulmonar e inserción de un dispositivo de asistencia ventricular izquierda. Durante los últimos años, varios estudios han demostrado el valor pronóstico de la función del ventrículo derecho en cirugía cardiaca y, por lo tanto, la utilidad de una adecuada estratificación del riesgo. La tasa de supervivencia a la insuficiencia del ventrículo derecho aguda y refractaria tras la cirugía cardiaca puede situarse en cifras tan bajas como un 20-25%. Grados menos graves se asocian también a un aumento de la morbimortalidad postoperatoria y tienen un notable impacto en la estancia hospitalaria. Esto destaca la relevancia de conocer su particular fisiopatología, espectro clínico, diagnóstico precoz y estrategias de prevención, aspectos todos ellos tratados en este artículo de revisión (AU)

Right ventricular failure after cardiac surgery remains an important clinical problem, especially in certain surgical settings: congenital heart disease, mitral valve disease with pulmonary hypertension, high-risk coronary artery disease, heart transplantation, pulmonary thromboendarterectomy and left ventricular assist device placement. In recent years, a number of studies have demonstrated the prognostic value of right ventricular function in cardiac surgery and, therefore, the usefulness of accurate risk stratification. The survival rate for acute, refractory, right ventricular failure after cardiac surgery may be as low as 20-25%. Less severe disease is also associated with increased postoperative morbidity and mortality and has a marked effect on the length of hospitalization. This highlights the importance of understanding the underlying pathophysiology of the condition, its clinical spectrum, early diagnosis and preventive strategies, all of which are discussed in this review article (AU)

Respuesta comunitaria a la muerte súbita: resucitación cardiopulmonar con desfibrilación temprana / Responding to sudden death in the community: cardiopulmonary resuscitation with prompt defibrillation

La respuesta a la parada cardiaca extrahospitalaria debe ser una prioridad para todos los sistemas sanitarios por su elevada incidencia y sus dramáticas consecuencias. Es la tercera causa de mortalidad en las sociedades avanzadas. La estrategia asistencial descansa en los cuatro eslabones de la «cadena de supervivencia»: la alerta inmediata, el soporte vital básico realizado por los testigos, la desfibrilación temprana y, por último, el soporte vital avanzado precoz, seguido de los cuidados intensivos tras la resucitación. La efectividad de esta cadena está condicionada por su eslabón más débil; los elementos clave para la supervivencia son las compresiones torácicas precoces, realizadas con mínimas interrupciones, y la desfibrilación temprana. La introducción del desfibrilador externo semiautomático ha hecho posible que se plantee como objetivo realista lograr un tiempo de desfibrilación < 5 min. Su utilización por los servicios de emergencias sanitarios y cuerpos de seguridad es efectiva y eficiente, como también lo es su introducción en espacios públicos adecuadamente seleccionados, aunque en este caso su eficiencia puede variar significativamente según las características y el nivel de riesgo del espacio donde se ubiquen (AU)

Responding to an out-of-hospital cardiac arrest should be a priority for all health-care systems because of the high incidence and dramatic consequences of such events. Cardiac arrest is the third leading cause of mortality in developed countries. The strategy for providing emergency assistance is based on the four links of the «chain of survival»: rapid notification of the emergency services, the provision of basic life support by bystanders, prompt defibrillation and, finally, prompt provision of advanced life support, followed by post-resuscitation intensive care. The effectiveness of this chain of events depends on its weakest link and the key elements for survival are prompt chest compression, carried out with minimal interruption, and prompt defibrillation. The development of semiautomated external defibrillators has made it possible to regard carrying out defibrillation within 5 minutes as a realistic objective. Their use by emergency health services and by first-aid facilities is effective and efficient, as is their introduction into properly selected public areas. However, in public areas, their efficiency could be significantly affected by the nature of the area in which they are located and by the level of risk at that location (AU)