Via aerea en paciente de neuro
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Este documento describe el abordaje de la vía aérea en pacientes neurológicos en la sala de emergencias. Explica los criterios para intubación, la secuencia rápida de intubación para preservar la perfusión cerebral, y los cuidados posteriores a la intubación como la monitorización de la presión intracraneal, la ventilación y la sedación. El objetivo es asegurar una adecuada oxigenación y ventilación mientras se previene la lesión secundaria en el cerebro.
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Via aerea en paciente de neuro
- 1. MANEJO DE LA VIA AEREA EN EL PACIENTE NEUROLOGICO DE URGENCIAS Ana María Ángel Isaza R1 Medicina de Emergencias Universidad Icesi
- 2. OBJETIVOS • Describir el abordaje de vía aérea del paciente con compromiso neurológico en el área de urgencias • Describir el cuidado post intubación
- 3. Urgencias Neurológicas Generadora de mortalidad y discapacidad Alta carga social y económica Requieren una evaluación y manejo inicial apropiado Manejo adecuado de la vía aérea, oxigenación y ventilación son fundamentales para la supervivencia y pronostico Introducción
- 4. Hipertensión Intracraneana TCE: mortalidad 125x100.000 hab ECV: 24,5-33,5% Urgencias Neurológicas 2,6 -14% Epidemiologia V. Casado. Atención al paciente neurológico en los Servicios de Urgencias. Revisión de la situación actual en Espana. Neurología. 2011;26(4):233—238Ara JR, Marrón R, Torné L, Giménez A, Sánchez B, Povar J, et al. Características de la demanda de atención neurológica urgente en un hospital terciario. Estudio mediante el sistema espanol ˜ de triaje. Neurología. 2007;22(9):666—824
- 5. Objetivos del manejo Adecuada oxigenación y ventilación Preservar la perfusion cerebral Prevenir la broncoaspiración Evitar la lesión secundaria Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20.
- 6. Evaluación Neurológica • Nivel de conciencia glasgow • Orientacion, lenguaje • Nervios craneales • Pupilas • Funcion motora • Reflejos • Inestabilidad cervical • Signos de fractura de base de creneo Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20. Registrar en la Hc
- 7. No protección via area Incapacidad para lograr oxigenación o ventilación Condiciones clínicas anticipadas: Probabilidad de deterioro o perdida de la VA Intervenciones terapéuticas Transporte Criterios de Intubación Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20.
- 8. Evaluación de la Vía Aérea Predice ventilación difícil Calvin A. Brown III. Ali Raja. The traumatized Airway. Capitulo 41, Parte 5. Dificult Airway Situations. En Benumof y Hagbergs Airway Management. Third edition. Elsevier Saunders 2007. paginas 859-875 Predice VA difícil
- 9. Intubación del paciente con patología intracraneal Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20. Secuencia de Induccion Rapida Evitar elevación de la PIC Preservar la perfusión y oxigenación cerebral Disminuir posibilidad de broscoaspiracion Suponer que hay elevación de la PIC
- 10. Secuencia de Intubation Rapida verificación
- 11. Preparación • Evaluar vía aérea • Plan • Equipos • Medicamentos
- 12. Pre oxigenación • MascaraOxigeno 100% x 5 min 4 CV SpO2: - 90%: • Con BVM y oxigeno al 100% a 10 l/min 3 a 5 minutos
- 13. Posicionamiento ¿Sospecha de TRM? Vía Aérea con control de la columna cervical Alineación Neutra Estabilización Alineada Manual
- 14. Mascara laríngea Estilete luminoso Fastrach Combitubo
- 15. No TRM Posicionamiento Burney RE, Maio RF, Maynard F, et al: Incidence, characteristics and outcome of spinal cord injury at trauma centers in North America. Arch Surg 128:596–599, 1993 Berne JD, Velmahos GC, El-Tawil Q, et al: Value of complete cervical helical computed tomographic scanning in identifying cervical spine injury in the unevaluable blunt trauma patient with multiple injuries: A prospective study. J Trauma 47:896–902, 1999..
- 16. Pre medicacion Medicamento Dosis Inicio Duración (min) Precaución Lidocaína 1.5 mg/kg 45 -90seg 10-20 Bloqueo Av completo, alergias convulsion Fentanyl 2-3 mcg/kg 2-3 min 30-60 Hipotensión Evitar Respuesta simpática x laringoscopia Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20.
- 17. No evidencia de que la lidocaina en SIR disminuya la PIC o mejore el descenlace neurologico Evidencia: 42 pte premedicados en neurocirugia electiva. No en SIR (Emerg Med J 2001;18:453–457)
- 18. Inducción Medicamen to Dosis Inicio Duración (min) Efecto Precaución Propofol 1 mg/kg 30-50 seg 3-10 FSC: CMRO2: PIC: Hipotension Etomidato 0.2 mg/kg 30-60 seg 3-5 FSC: CMRO2: PIC: Disminuye el umbral de convulsión Insuf suprarrenal Tiopental 1.5 mg/kg 30-60 seg 5-15 FSC: CMRO2: PIC: Hipotension, broncoespasmo Ketamina 1 -1.5 mg/kg 1-2 min 5-15 FSC: CMRO2: PIC: Posible incremento PIC
- 21. Parálisis Relajación muscular Meta: sedación + parálisis 45-60 seg después que se administran los medicamentos iv Medicamento Dosis Inicio seg Duración min Succinilcolina 1.5 mg/kg 30-60 5-15 Rocuronio 1.2 mg/kg 45-60 45-70
- 22. Abordajes Alternativos Vía aérea difícil • Usar dispositivos para para facilitar la iot - bougie, estilete luminoso, king vision, Fastrach • Dispositivos supragloticos • Vía aérea quirúrgica Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20.
- 23. Prueba- Confirmación Rx solo para determinar la profundidad del tubo Auscultacion
- 24. Post intubación • Cabecera 30 grados • Evitar hipotension arterial • Normocapnia – Capnografia • Monitorizacion • Sedacion • Evitar hipertermia e hipoglicemia Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20. METAS TAM 80-90 mmHg PIC -20 mmHg CPP 60 mmHg SpO2: +92% PaCO2: 32-37 mmhg PaO2 +60mmHg Modo controlado (relajado)
- 25. Umbrales de Presión Arterial Metas TCE PAM > 90 mmHg Si PIC, PAM que garantice PPC 60-70 mmHg Hematoma cerebral espontaneo PAM100-110mmHg pas <140 Si PIC, PAM que garantice PPC 60-70 mmHg Hemorragia subaracnoidea PAS 90-140mmHg si aneurisma roto no exluido Si excluido <200mmHg Ictus isquemico Candidato fibrinolisis: PAS <185 PAD <110 No candidatos: reducir 15% Si PAS>220 PAD >120 mmHg Posparo PAM >65 Paniagua M. et al. Soporte neurocritico. Distribuna. 2014
- 26. FSC Flujo Sanguíneo Cerebral Hiperventilación Hiperventilación PIC Presión Intracraneal Vasoconstriccion pCO2 20 mmHg PPC Presión perfusión cerebral Isquemia Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20. Terapia puente
- 27. Sedación • Disminuye Consumo O2 cerebral • Disminuye PIC • Disminuye actividad simpática • Tolerancia VMI • Aumenta umbral convulsivo Seder, D, Jagoda A, Riggs B. Emergency Neurological Life Support: Airway, Ventilation, and Sedation. Neurocrit Care. 2012:S4-20. • Propofol • Midazolam • Fentanil
- 28. Monitoria Sedación Escala de la Agitación y Sedación Richmond Ann Emerg Med. 2007 Dec;50(6):653-65. Epub 2007 Aug 3.
- 29. TRAUMA CRANEO ENCEFALICO Y ELEVACION DE LA PRESION INTRACRANEAL • Injuria secundaria: hipotensión, hipoxemia, elevación PIC Roppolo and Walters.Airway Management in Neurological Emergencies. Neurocritical Care.2004;405-414 Tac es la imagen de eleccion: Glasgow -13 = tac Deterioro del nivel de conciencia G >2puntos Pupilas asimetricas- dilatadas y no reactivas Postura de decorticacin o respuesta motor Triada de Cushing - Hipertension arterial -Bradicardia -Alteracion del patron respiratorio
- 30. Rev Colomb Anestesiol 2015;43 Supl 1:3-8 - Vol. 43 DOI: 10.1016/j.rca.2014.07.004
- 31. Rev Colomb Anestesiol 2015;43 Supl 1:3-8 - Vol. 43 DOI: 10.1016/j.rca.2014.07.004
- 32. GRACIAS
Notas del editor
- Hipotension hipoxemia morbilidad
- tamaño y reactividad a la luz. Una diferencia mayor de 1 mm en tamaño o asimetría en la respuesta a la luz debe ser considerada anormal.
- Estado de consciencia alterado Escala de Glasgow <8 ---- Perdida de reflejos protectores
- Regla: 3-3-2 - Apertura - Mentón al hueso hioides Hioides a tiroides Escala rápida, validada en urgencias Anticipa VA difícil Muy sensible
- Rapid sequence intubation (RSI) is the preferred method of securing the airway in patients with suspected elevated ICP. RSI limits elevation of ICP often associated with the physiologic responses to laryngoscopy [4–7]. The presence of coma should not justify proceeding without pharmacological agents, or administration of only a neuromuscular blocking agent without appropriate pre-treatment and induction agents. Although the patient may seem unresponsive, laryngoscopy and intubation often provoke reflexes that elevate ICP unless appropriate pre-treatment and induction agents are used [8]. Outcomes in patients with intracranial catastrophes are related to the maintenance of both brain perfusion and oxygenation. Consequently, close assessment and preservation of these two parameters are critical. Cerebral perfusion pressure (CPP) is the physiologic correlate for blood flow to the brain and is measured by the difference between the mean arterial pressure (MAP) and the ICP: CPP = MAP – ICP It is generally recommended that the ICP be maintained below 20 mmHg, MAP between 80 and 110 mmHg, and CPP at a minimum of 50 mmHg [9]. The needs of the individual patient are variable, and perfusion goals should consider these distinctions. Because the ICP may not be known at the time of urgent intubation, clinicians should anticipate elevated ICP in patients with a mass lesion, such as hematoma, hydrocephalus, tumor, or cerebral edema, and choose an appropriate BP target accordingly. When the airway is manipulated, two responses may exacerbate intracranial hypertension. The reflex sympathetic response (RSR) results in increased heart rate, increased blood pressure, and, consequently, increased ICP. The direct laryngeal reflex stimulates an increase in ICP independent of the RSR [3]. Although the RSR may be dangerous in a hypertensive patient, pre-treatment of the RSR is not indicated in a hypotensive patient with known or suspected increased ICP [10]. Elevations in ICP should be mitigated by minimizing airway manipulation (the most experienced person should perform the intubation) and administering medications. Clinicians must recognize that many neurologically impaired patients have compromised cerebral blood flow (CBF) even with a normal ICP. For example, patients with ischemic stroke, vasospasm, and hypoxic-ischemic brain injury often have impaired auto-regulation and are each critically sensitive to decreases in blood pressure and CBF. In these patients, particular efforts should be made to maintain MAP and CPP goals. Vasodilators, which reverse physiological shunting, should be avoided in this patient population. Common pre-medications used to prevent increased ICP during intubation include
- Preparacion: Cabecera elevada Accesos venosos Cristalodides Medicamentos listos Preoxigenacion: 6-9 ventilaciones en apnea Evitar hipotension- Hipoventilacion Mascara con bolsa Post intubación Cabecera 30 g Metas Co2 30 -40 Monitorizar Rx de torax (23).
- Preoxigenacion – desnitrogenicacion– sat02 Aumentar reserva O2 Retrasar de saturación durante apnea Pte inmovilizado: trendelemburg
- minimizar los movimientos cervi- cales en pacientes traumatizados con sospecha de lesión de columna cervical o torácica alta, así como para atenuar la respuesta cardiovascular inherente a la maniobra de larin- goscopía e intubación y a la labilidad en este tipo de lesio- nes traumáticas. Pacientes con Glasgow < 15, con dolor cervical o deformidad anatomica evidente, o cuando los mecanismos del trauma sugieran lesion cervical, requieren inmovilizacion cervical inicial y posteriormente con un collar cervical de talla adecuada, tabla espinal y soportes laterales con cintas de sujecion alrededor de la frente. 2 Aquellos con lesiones por encima de las clavÌculas estn en mayor riesgo, que aumenta cuatro Glasgow
- La intubación orotraqueal bajo laringoscopía directa re- quiere de la elevación de la epiglotis y la exposición de la apertura glótica. Ambas se obtienen por un movimiento ha- cia arriba y adelante de la hoja del laringoscopio, ejercida a lo largo del eje de la mano del laringoscopista, produciéndo- se así la estimulación refleja de la vía aérea dando como resultado la respuesta cardiocirculatoria. La intubación traqueal a través de la transiluminación de los tejidos blandos de la cara anterior del cuello usando el estilete luminoso, es una técnica gentil que no requiere de elevación de la epiglotis ni exposición de la abertura glótica, por lo tanto, esta técnica alternativa de intubación causaría menores cambios en el comportamiento cardiovascular que la laringoscopía directa
- Consiste en el desplazamiento manual externo de la laringe mediante presión sobre el cartílago tiroides (a diferencia de la presión cricoidea) en tres direcciones: Atrás (backward), hacia las vértebras cervicales. Arriba (upward), tan lejos como se pueda (aunque no se recomienda más de 3 cm) y ligeramente a la derecha del paciente ejerciendo presión: Rightward Pressureo
- The administration of 1.5 mg/kg of lidocaine helps to attenuate the cardiovascular response to intubation, suppress the cough reflex, and mitigate the increase in intracranial pressure (ICP) response to intubation (18–20). Opioids, specifically fentanyl, may significantly attenuate the sympathetic response to intubation (21). Fentanyl has the greatest utility in patients with conditions at risk of worsening from increasing blood pressure (e.g., increased ICP) or vascular shear forces (e.g., aneurysm or penetrating vascular trauma patient) associated with laryngoscopy (22). Fentanyl also has the benefit of sedation and analgesia; however, caution must be used in blunting the sympathetic response in a patient in shock who is dependent on their sympathetic drive for cardiovascular stability. Atropine is recommended in children less than 5 to 10 years of age to blunt the potential vagal response of bradycardia resulting from laryngoscopy and the use of succinylcholine β-blockers, particularly esmolol, also may reduce the incidence and severity of the hypertensive and tachycardic responses to tracheal manipulation (26). The pretreatment agents should be given approximately three minutes prior to laryngoscopy
- SI mayor a 1: Especificiad 96% Sensibilidad18%.
- Nmda y ketam lo activa y yo quiero es bajarlo A favor y en contra Etomidate Etomidate is a short-acting imidazole derivative that provides sedation and muscle relaxation with minimal hemodynamic effect. It is considered the most hemodynamically neutral induction agent of all commonly used induction agents and a drug of choice for patients with elevated ICP [13, 14]. Etomidate is the most widely used in the ED in light of its rapid onset, short duration, excellent pharmacodynamics, protection from myocardial and cerebral ischemia, minimal histamine release, and a hemodynamic profile that is uniquely stable (27–29). Disadvantages include a lack of blunting of the sympathetic response to intubation, a high incidence of myoclonus, prominent nausea and vomiting, potential activation of seizures in patients with epileptogenic foci, and impaired glucocorticoid response to stress Propofol At a dose of 2 mg/kg intravenous (IV) push, propofol is an alternative induction agent. However, it is also a potent vasodilator that may cause hypotension and may not be appropriate for patients with threatened cerebral perfusion, unless concurrently administered with a vasopressor agent Another potential agent is propofol, which has profound amnestic properties and reliable prompt awakening. This makes propofol an ideal agent in clinical situations in which frequent neurological assessments are warranted (30). It also attenuates potential rises in ICP, but it does so at the expense of cerebral perfusion pressure and may cause myocardial depression as well (32). Propofol is known to depress pharyngeal and laryngeal muscle tone and reflexes more than any other intravenous induction agent and may be used in combination with an opioid agent alone when neuromuscular paralysis is contraindicated Thiopental At a dose of 3 mg/kg IV push, thiopental confers cerebroprotective effect by decreasing the basal metabolic rate of oxygen utilization of the brain (CMRO2) and CBF, thus decreasing ICP. However, it is a potent venodilator and negative inotrope with a strong tendency to cause hypotension and reduce CPP, even in relatively hemodynamically stable patients [8]. thiopental is a favorable induction agent for patients with status epilepticus or increased ICP owing to its cerebroprotective effect. It causes cerebral vasoconstriction, reduces cerebral blood volume, and decreases ICP (30). However, one major adverse effect of sodium thiopental is hypotension (31) Ketamine Ketamine is a hemodynamically neutral dissociative agent administered at a dose of 2 mg/kg IV push. Historically, use of ketamine was generally avoided due to concerns related to ICP elevations. However, recent evidence suggests that when concurrent sedation is provided, it is safe in patients with elevated ICP. Its favorable hemodynamic profile may lead to more widespread use as an induction agent. Ketamine causes cardiovascular stimulation, bronchodilation, and increases ICP (30). Its use in the ED is generally reserved for severe asthmatics because of its bronchodilator effects. Midazolam is another agent with anticonvulsant activity but may also cause hypotension at high doses (31). the induction agent, similar intubation conditions were created between succinylcholine and rocuronium, one of the short-acting nondepolarizing agents currently available (38). There are specific neurological conditions in which succinylcholine should be avoided. Certain disease states cause an exaggerated release of potassium in response to succinylcholine, which is a result of an upregulation of acetylcholine receptors. Examples include spinal cord injury, stroke, muscular dystrophy, multiple sclerosis, Guillain-Barré Syndrome (GBS), and other conditions that cause prolonged immobility (40,41). The period of susceptibility to succinylcholine-induced hyperkalemia is not well-defined, but its use appears to be safe within the first 24 hours of an acute insult (41). Regarding denervation injuries, this risk is not detected until four days after the injury (42) and lasts throughout the first 6 months following the injury or illness (43). Patients with neuromuscular disorders such as multiple sclerosis or amyotrophic lateral sclerosis may be at risk for hyperkalemia indefinitely, depending on the dynamic state of their disease process (43). Finally, in contrast to the increased sensitivity to succinylcholine in conditions associated with an upregulation of acetylcholine receptors, there is resistance to nondepolarizing neuromuscular blockers, and the requirement for these agents may be increased in these patients (44). The unique circumstances of each neurological condition dictates what pharmacological agents should be used for RSI, as will be discussed later.
- Alternative airway devices are often required when a “difficult” airway is encountered—defined as a situation in which a patient cannot be intubated or ventilated by standardtechniques. These techniques include bag-valve mask (BVM) ventilation, nasotracheal intubation, or oral intubation with and without the use of pharmacological manipulation. Fortunately, the frequency of occurrence is low according to the National Airway Registry. In this study, only 0.56% of 7712 patients who required emergent intubation underwent surgical cricothyrotomy after failure of RSI or other intubation method (45). Essentially, three options exist for the truly difficult airway: (a) use devices intended to facilitate placement of an ETT, (b) place a temporizing device, or (c) establish a surgical airway This semirigid device is a 60-cm-long stylet with a 15-Fr (5-mm) diameter that is advanced posterior to the epiglottis with the aid of direct laryngoscopy. There is a 40º angulation located 3.5 cm from its distal tip to facilitate entrance into the larynx. Fiberoptic intubation is another option for intubating a patient with a difficult airway. Flexible fiberoptic intubating scopes can be used for selected patients, particularly those in whom paralysis or laryngoscopy would be contraindicated or difficult (48). ASeveral devices can be temporarily placed in the airway to facilitate oxygenation and ventilation; however, they are not definitive airways in that a cuffed ETT is not placed within the trachea. The two most commonly used options available include the Combitube™ and the laryngeal mask airway (LMA). With blind insertion, the Combitube™ is successfully placed in the esophagus more than 95% of the time. Ventilation occurs through perforations in the pharyngeal lumen as air is forced into the trachea after being unable to escape through other orifices. Success rates for the Combitube™ have been reported to be as high as 97% (50). The LMAconsists of a semirigid tube attachment and an inflatable mask that is easily placed over the hypopharynx and advanced over the larynx. When inflated, the mask forms a seal over the glottic opening. One multicenter trial, of the intabating laryngeal mask airway reported an overall success rate of 96.2%
- Hypoxia increases ICP and can exacerbate brain injury. Please note that during hypothermic conditions, PaO2 and pCO2 should be corrected for acquisition temperature Normalization of oxygenation utilizing the lowest FiO2 that will maintain hemoglobin saturation >94 % • Normalization of ventilation to achieve a systemic pH of 7.3–7.4, and pCO2 or ETCO2 to 30–40 mmHg • Normalization of the work of breathing • Prevention of ventilator-induced lung injury
- líquidos hipertónicos, drenaje de LCR, olíquidos y medicamentos vasoactivos que mejoren la PAM Hiperventilacion: aumento resistencia vascular cerebral, reduce flujo sanguineo cerebral global, reduce volumen sanguineo, reduce PIC Terapia puente
- One prospective, randomized trial of 67 mechanically ventilated adult patients sedated with propofol showed that the BIS monitor added to routine sedation scale monitoring significantly reduced the propofol dose and the time to awakening when compared to subjective scale monitoring alone
- -fourth suffering from increased ICP(62). Although the only treatment for primary brain injury is prevention, the next most important factor is avoidance of secondary insult. Studies have shown that secondary insult is most commonly related to hypotension, hypoxemia, and further increases in ICP (63). Airway management is a common issue in the patient with head trauma. One study found that over 50% of patients with head trauma were hypoxic at the scene (64). Therefore, airway management in the patient with a traumatic brain injury (TBI) presents a fairly common situation with specific concerns for which the treating physician must be prepared. There are many concerns specific to intubation of the patient with a presumed TBI. Because of the perceived risk of intracranial placement, it has been recommended that orotracheal intubation be performed rather than nasal intubation, especially in those patients with obvious facial fractures. However, thiscomplication was not reported in more recent studies (65). Concomitant cervical spine injuries are found in 3–8% of patients with head trauma; therefore, any manipulation of the spine must be strictly avoided (66). Finally, intubation has the potential to be quite challenging, especially in those patients with multiple facial fractures or a poor visual field secondary to blood or secretions in the oropharynx. Thus, difficult airway equipment must always be readily available. Rapid sequence intubation is the method of choice for intubating these patients because it minimizes the adverse effects associated with the procedure. Etomidate and succinylcholine are the most commonly used induction and paralytic agents in trauma patients, and TBI is no exception. Increased ICP should be suspected in all patients presenting with head trauma. Increases in ICP associated with intubation can be minimized with lidocaine, fentanyl, and a defasciculating dose of paralytics in the pretreatment phase of RSI. Fentanyl may cause hypotension in the trauma patient and should be used with caution. Deliberate mechanical hyperventilation increases cerebral vascular resistance, reduces global cerebral bloodflow, reduces cerebral blood volume, and thereby reduces ICP (67). Unfortunately, this effect is only good for short periods of time. The previous dogma for hyperventilation in patients with TBI is no longer routinely recommended (68). One study suggested that even brief periods of hyperventilation may significantly increase extracellular concentrations of mediators of secondary brain injury as a result of ischemia (69). The only reasonable purpose for hyperventilation is to treat acute increases in ICP; however, hyperventilation should only be used for a very short period of time until other means of reducing ICP become available (70)