Medicina intensiva en Chile: desafíos para su desarrollo. Documento de la Comisión Nacional de Medicina Intensiva del Ministerio de Salud / Ministry of Health Intensive Care Medicine Commission: Proposals for the development of the discipline

Intensive care medicine in Chile is still in its dawn. It has experienced a progressive growth in the last decade, but continues to be weak. Although investments in the discipline have increased fivefold, there is still a severe deficiency of intensive care specialists. This issue will represent a serious problem in the near future. The Ministry of Health gathered an expert committee to study the problem and propose solutions for the future development of the discipline.

Manejo del paciente en shock séptico / Management of the septic shock patient

El shock séptico es la manifestación más grave de una infección. Esta se produce como consecuencia de una respuesta inflamatoria sistémica severa que lleva a un colapso cardiovascular y/o microcirculatorio, y a hipoperfusión tisular. La hipoperfusión constituye el elemento central que define la condición de shock y esta debe ser detectada y revertida en forma urgente desde la atención inicial. La evaluación de la perfusión periférica, la diuresis, y la medición del lactato y de la saturación venosa central, son las principales herramientas para evaluar la perfusión sistémica. La reanimación debe comenzar en forma inmediata con la administración agresiva de fluidos, la cual puede ser guiada por parámetros dinámicos de respuesta a fluidos, y continuada hasta normalizar u optimizar las metas de perfusión. En forma paralela se debe iniciar vasopresores en caso de hipotensión marcada, siendo el agente de elección noradrenalina, y conectar precozmente al paciente a ventilación mecánica frente a hipoperfusión severa que no responde a fluidos, o frente a un aumento del trabajo respiratorio. Adicionalmente, el foco infeccioso debe ser tratado agresivamente iniciando antibióticos lo antes posible.

Septic shock is the most severe manifestation of an infection. It is caused by a systemic inflammatory response syndrome, which leads to cardiovascular and/or microcirculatory failure, and to tissue hypoperfusion. Hypoperfusion is the most important feature, which defines the shock state, and which must be detected and treated urgently from the very first attention. Peripheral perfusion, urine output, and lactate and central venous saturation measurements, are the main tools to assess systemic perfusion. Resuscitation must start immediately with fluid administration, which can be guided by dynamic predictors of fluid responsiveness, and continued until normalizing or optimizing perfusion goals. In the presence of hypotension, vasopressors should be started in parallel, with noradrenaline being the preferred option. If hypoperfusion persists, or if respiratory work is too high, mechanical ventilation should be started promptly. In addition, infection should be treated aggressively starting antibiotics as soon as possible.

Evaluación de la microcirculación sublingual en un paciente en shock séptico refractario tratado con hemofiltración de alto volumen / Evaluation of sublingual microcirculation in septic shock: report of one patient treated with high volume hemofiltration

Microcirculation is severely compromised in sepsis, with a reduction of capillary density and flow impairment. These alterations have important prognostic implications, being more severe in non-survivors to septic shock. Today microcirculation may be assessed bedside, non-invasively usingpolarized light videomicroscopy a technique known as SDF (side dark field). We report a 54 year-old man with an extramembranous nephropathy that developed a necrotizing fascitis associated to septic shock, in whom microcirculation was periodically assessed during his management. The patient was treated with Buids, vasoactive drugs, antibiotics and was operated for exploration and debridement. As the patient persisted in refractory shock despite treatment, high-volume hemofiltration was started. Before hemofiltration the patient had severe microcirculatory alterations that improved during and after the procedure. Physiologic endpoints of high-volume hemofiltration in septic shock remain unknown, but it has the capacity to clear inflammatory mediators. Since microcirculatory alterations are in part secondary to these mediators, their removal is beneficial. Like other authors, we found no relation between microcirculation and other haemodynamic and perfusion variables.

Ventilación diferencial en el manejo del síndrome de distress respiratorio agudo secundario a mediastinitis necrotizante descendente: rol de la tomografía axial computarizada dinámica de pulmón / Use of dinamic lung computed tomography to orient mechanical ventilation in adult respiratory distress syndrome: report of 1 case with acute mediastinitis

Lung computed tomography (CT) is being used increasingly to assess lung morphology in patients on mechanical ventilation. Lung CT under known levels of airway pressure (dynamic CT) can also assess the response of lung parenchyma to ventilatory therapy. We report a patient with acute respiratory distress syndrome secondary to descending necrotizing mediastinitis, in whom lung dynamic CT oriented ventilatory management. Independent lung ventilation improved gas exchange and helped patient recovery

Cateterización venosa suprahepática en cuatro casos de shock séptico severo / Suprahepatic vein oxygen saturation monitoring and gastric tonometry in the management of severe septic shock: report of 4 cases

Splanchnic hypoperfusion, with pathogenic implications for multiple organ failure, can occur during septic shock. We report four patients with septic shock in whom regional hepatosplenic splanchnic perfusion was monitored through suprahepatic vein catheterization and gastric tonometry. Suprahepatic lactate and oxygen saturation showed splanchnic hypoperfusion in all patients. These parameters improved only in the patient that survived. Gastric tonometry was more inconsistent. We conclude that suprahepatic vein catheterization could have a role in the management of septic shock

Ventilación con presión positiva no invasiva, VPPNI, en pacientes con insuficiencia respiratoria aguda hipoxémica / Noninvasive ventilation with positive pressure in patients with acute hypoxemic respiratory failure

Quisimos evaluar la aplicabilidad y eficacia de la ventilación con presión positiva no invasiva (VPPNI) en pacientes con insuficiencia respiratoria aguda (IRA) hipoxémica y aumento del trabajo respiratorio. En un periodo de 10 meses evaluamos a 64 pacientes que ingresaron a nuestro servicio con el diagnóstico de IRA y signos de fatiga muscular, en ausencia de patología crónica. Fueron considerados no aptos para VPPNI quienes tuvieran compromiso de conciencia importante, inestabilidad hemodinámica o más de dos órganos en falla, cirugía reciente de esófago, estómago o duodeno, hemorragia digestiva alta activa, distensión abdominal importante o dificultad en el manejo de secreciones. Luego de aplicar los criterios de exclusión, 14 (23 por ciento) pacientes fueron sometidos a VPPNI por un periodo de 1 a 9 días. La Pa/FiO2, sin cambios significativos en la PaCO2 y frecuencia respiratoria. En 5 pacientes (36 por ciento) fracasó el método, de los cuales 2 fallecieron. Un paciente presentó una escara nasal. Por su mínima invasividad y fácil aplicación, la VPPNI debe ser considerada precozmente en todo paciente con IRA hipoxémica con buen nivel de conciencia y que preserve su ventilación espontánea

Síndrome de respuesta inflamatoria sistémica severa: ¿es comparable a la sepsis severa? / Systemic inflammatory response syndrome: is it similar to severe sepsis?

Background: in 1992, a consensus conference defined the terms systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis and septic shock. Since then, numerous reports have validated the prognostic usefulness of these operative definitions. Aim: to evaluate if sepsis severity criteria, as defined by the Consensus Conference, can be applied to noninfectious SIRS. Patients and methods: five hundred eighteen patients admitted to 5 intensive care units (ICU) from 4 hospitals were prospectively evaluated during a 3 months period. Patients that met at least one severity criteria were included. SIRS etiology, organ dysfunction and evolution were recorded in each patient. Results: One hundred two patients were included: 79 with sepsis (group I) and 23 with noninfectious SIRS (group II). ICU and hospital mortality were comparable (43 and 48 percent in sepsis compared to 43 and 51 percent in non infectious SIRS). The most common sources of sepsis were pneumonia and peritonitis. Group II patients had a wide variety of diseases. ICU stay, APACHE score and number of organs with dysfunction were not different among groups. Only the incidence of renal dysfunction was higher in the septic group. Conclusions: The Consensus sepsis severity criteria can be applied to noninfectious SIRS, defining a population subset with similar high mortality and organ dysfunction incidence, although with greatly heterogeneous etiologies

Efecto agudo de dobutamina y amrinona sobre la hemodinamia y perfusión esplácnica de pacientes en shock séptico / Acute effect of dobutamine and amrinone on hemodynamics and splanchnic perfusion in septic shock patients

Background: Vasoactive drugs used in the reanimation of septic patients, can modify splanchnic perfusion. Aim: To compare the effects of dobutamine and amrinone on gastric intramucosal pH (pHi), lactate levels and hemodynamics in surgical patients with compensated septic shock. Patients and methods: Fourteen postoperative patients with abdominal sepsis and compensated septic shock (pHi <7.32 or lactate >2.5 mmol/l) were studied in a prospective, randomized, unblinded study. Patients were randomized to receive (Group 1, n=7) dobutamine at 5 µg/Kg/min or (Group 2, n=7) amrinone at 5 µg/Kg/min. Hemodynamic data, arterial lactate and pHi were measured before and 30, 60 and 120 minutes after starting drug infusion. Results: Both drugs were associated with a decrease in lactate levels. Dobutamine infusion, but not amrinone, increased gastric pHi, as well as cardiac index and oxygen delivery. Conclusions: An improvement in gastric pHi associated with an increase in oxygen delivery, was observed with dobutamine. Amrinone showed no effect at the fixed, low dose used in the study

Epidemiología del traumatismo encefalocraneano en niños del área suroriente de Santiago / Epidemiology of head injuries in children at Santiago's southwest area, Chile

Se estudiaron retrospectivamente las características epidemiológicas del traumatismo encéfalocraneano en 286 pacientes ingresados con ese diagnóstico a un hospital general del Servicio de Salud Metropolitano Sur-Oriente de Santiago de Chile, entre enero 1993 y abril 1995. La edad promedio de los pacientes era 6.1 años, 4,7 por ciento eran varones, 34,5 por ciento escolares (5 a 14 años) 25,2 por ciento preescolares (2 a menos de 5 años) y 20,3 por ciento lactantes (menores de 24 meses). En los lactantes y preescolares el accidente ocurrió con más frecuencia en el hogar (78,6 por ciento y 60 por ciento respectivamente), en escolares en la vía pública (76,7 por ciento), En los primeros la principal causa del traumatismo fueron las caídas, en los escolares los accidentes de tránsito (65,6 por ciento). En 64,9 por ciento de los casos la consulta fue hecha en la primera hora. El estado de la conciencia al ingresar al hospital (escala de coma de Glashow), era 13 a 15 puntos en 76,9 por ciento de los pacientes, 9 a 12 puntos en 10,5 por ciento de ellos e igual o menor a 8 puntos en 10,8 por ciento, proporciones que son mayores que las descritas en otras series

Traumatismo encéfalocraneano en niños del área suroriente de Santiago / Head injuries in children at Santiago's southwest area, Chile

Se describen las características clínicas de 286 pacientes ingresados con el diagnóstico de traumaismo encéfalocraneano a un hospital público del Servicio de Salud Sur Oriente de Santiago entre enero de 1993 y abril de 1995. El puntaje de Glasgow se registró en 261 pacientes. De acuerdo al puntaje de Glasgow al ingreso, los pacientes fueron clasificados como traumatismo encéfalocraneano leve (Glasgow 13-15, n = 220), moderado (Glasgow 9-12, n = 30) o grave (Glasgow < 8, n = 31=. En 181 de ellos (n = 123, 28 y 30 respectivamente) se habían realizado tomografías axiales cerebrales. Se encontraron diferencias significativas para cada grupo en cuanto al registro de alteraciones en la tomografía (p < 0,003), necesidad de procedimientos de neurocirugía (p < 0,001),examen neurológico alterado al alta (p < 0,0001) y muerte (p < 0,01). Se encontró una relación significativa entre fractura de cráneo y alteraciones en las imágenes tomográficas encefálicas (p < 0,04=. La escala de Glasgow, a pesar de ser útil en la evaluación inicial de estos pacientes, no permite por sí sola descartar una complicación, para la que es preciso complementarla con vigilancia clínica e instrumental estrictas y exámenes complementarios de acuerdo a la evolución