Rapid Sequence Intubation (RSI) Drugs PDF

 Rapid Sequence Intubation— Why and How to do it KEY POINTS For clinicians with the requisite skills, rapid-sequence intubation should become the method of choice for tracheal intubation in emergencies, unless contraindicated. The emergency medicine literature suggests high succe...

 Rapid Sequence Intubation— Why and How to do it KEY POINTS For clinicians with the requisite skills, rapid-sequence intubation should become the method of choice for tracheal intubation in emergencies, unless contraindicated. The emergency medicine literature suggests high success rates and low morbidity with the use of RSI in experienced hands. “Successful” tracheal intubation does not by itself necessarily represent a successful outcome. The evidence favoring pretreatment medications is not compelling. Emphasis should instead be placed on preventing hypoxia and hypotension. If rapid oxygen desaturation occurs (or is likely to occur) with onset of apnea during an RSI, gentle bag-mask ventilation can and should be performed while awaiting onset of the muscle relaxant. Cricoid pressure has the potential to impair the view at laryngoscopy, cause difficulty with bag-mask ventilation (BMV) and impair extraglottic device (EGD) placement. Laryngoscopy and intubation should proceed only once the muscle relaxant has taken effect.   INTRODUCTION TO RAPID SEQUENCE INTUBATION (RSI) Historically, the term “RSI” has referred to Rapid Sequence Induction (of anesthesia) Emergency medicine the term RSI refers to Rapid Sequence Intubation The difference in Meaning refers to a different end-point: in the (OR), patients are intubated to provide anesthesia, while in the (ED), patients are anesthetized to facilitate tracheal intubation.  RSI in emergency care involves the use of a combination of specific pharmacologic agents to obtain optimal conditions for tracheal intubation. increase the likelihood of successful tracheal intubation and decrease complications results assume trained and experienced clinicians who have learned the process and are familiar with the drugs used.   RSI IN EMERGENCIES: WHY USE IT? RSI is not dependent on patient cooperation and, with appropriate preparation, can usually be expeditiously performed. Skeletal muscle relaxation facilitates conditions for direct laryngoscopy and intubation. Application of cricoid pressure may decrease the risk of aspiration. Drugs used during RSI may help control undesirable physiologic responses to laryngoscopy and intubation such as gagging, or increases in intracranial pressure (ICP), heart rate, or blood pressure. RSI has a high success rate in experienced hands.   RSI: DEFINITION AND THE PROCESS Rapid sequence intubation is a process that involves pharmacologically inducing unconsciousness and paralyzing the patient in a manner that facilitates tracheal intubation, while minimizing the risk of aspiration using application of cricoid pressure. “Rapid-sequence” refers to the fact that the induction agent and the neuromuscular blocker are given in quick succession, and are not titrated to effect. In addition, “rapid” can refer to the fact that one is taking the patient from a conscious state (with the airway protected by the patient) to the placement of a tube in the trachea with the cuff inflated (when the airway is again protected, this time by the ETT cuff) with as little intervening time as possible. RSI: HOW TO DO IT  1.Preparation Personnel: Airway management is not a one- person job. Equipment: Needed equipment should be assembled. Medications. All medications needed for pretreatment (if used), induction, and neuromuscular blockade should be drawn up and labeled. Rescue vasopressor agents - to manage postintubation hypotension. Positioning. The patient and clinician should be optimally positioned for the situation.  2. Preoxygenation Administration of 100% oxygen for 3–5 minutes in a normal healthy adult will result in “nitrogen washout” and the establishment of an oxygen reservoir using the functional residual capacity (FRC).  3. Pretreatment. Use of medications to prevent adverse physiologic effects resulting from laryngoscopy, or the use of succinylcholine. Historically, the term “pretreatment” has referred to the use of lidocaine, fentanyl, a defasciculation agent or atropine (in children) given at least 3 minutes prior to induction.  4. Pharmacologic Paralysis and Induction In this step, a potent sedative-hypnotic (e.g., propofol, etomidate, or thiopental) or other agent such as the dissociative amnestic ketamine is given with the goal of inducing unconsciousness. This should be done with the correct dose of an agent with rapid onset and with a side effect profile that minimizes exacerbating the patient’s underlying condition.  4. Pharmacologic Paralysis and Induction Dosing of induction agents is based on the patient’s weight and is adjusted down (or up) in consideration of the following factors: Age: Dosing is adjusted upward for the pediatric patient, and downward for the older patient. Volume status: Dosage should be adjusted downward in the hypovolemic patient. In the profoundly hypovolemic and hypotensive patient, induction agents, even in small doses, may be poorly tolerated. Patient co-morbidities: The patient with a depressed level of consciousness may need less induction agent, as is the case for a patient in a cardiogenic or other shock state. 5. Protection and Positioning (Application of Cricoid Pressure)  6. Placement and Proof (Intubation and Confirmation of Tube Placement ) After onset of the muscle relaxant, laryngoscopy and intubation should be performed. “Best look” laryngoscopy should always be undertaken. An assistant should hand the clinician the ETT in the correct orientation, so that the cords are continuously visualized once seen. Laryngoscopy and intubation should take less than 30–45 seconds in most patients.  7. Postintubation Management After tube placement, the cuff should be inflated immediately to minimize the period of time with an unprotected airway. If used, the stylet should be removed, if not already done. Cricoid pressure is released only after tracheal location of the ETT has been confirmed. The chest is auscultated for equality of breath sounds, and the tube is secured. A postinduction set of vital signs should be obtained early, with particular reference to the blood pressure.  Pharmacology relevant to tracheal intubation The aim of drug administration for direct laryngoscopy and tracheal intubation is to achieve sufficient tissue relaxation to allow insertion and positioning of the direct laryngoscope and to ensure that the vocal cords are open and non-reactive. These conditions are achieved at a price. Upper airway obstruction increases as consciousness is reduced. Airway patency can usually be achieved by a series of manoeuvres but these are particularly likely to fail in patients presenting with incomplete airway Protection against pulmonary aspiration is decreased as consciousness is reduced. The pharmacological approach most frequently used is a combination of intravenous anaesthetic with neuromuscular blockade. (WALLS)  Airway Pharmacology adam law Airway management, including endotracheal intubation, requires a competent understanding of airway pharmacology. A small number of medications are used to facilitate airway management, for various indications. Successful airway intervention without patient compromise requires a good working knowledge of these agents, together with an appreciation of expected physiological responses to manipulation of the airway. (LAW)  THE PHYSIOLOGIC RESPONSE TO LARYNGOSCOPY AND INTUBATION Laryngoscopy and intubation are powerful stimuli that can provoke intense physiologic responses from multiple body systems. These responses includudes: hypertension, tachycardia, increased intracranial pressure (ICP), and bronchoconstriction, are generally transient, - little consequence in most individuals. -some patients, if these responses are not attenuated, significant morbidity may ensue. For the patient requiring emergency airway management, preservation of oxygenation and blood pressure often takes priority over attenuation of undesirable reflexes. Stimulation of the oropharynx and upper airway activates both arms of the autonomic nervous system. In adults, the sympathetic response usually predominates, with an increase in circulating levels of catecholamines. In young children (and some adults) airway instrumentation may cause a predominately vagal response, including bradycardia. Systems primarily affected by direct laryngoscopy and/or intubation include the cardiovascular, respiratory, and central nervous systems. When indicated, local anesthesia and systemic medications can be used to minimize these undesirable effects.  Cardiovascular Response to Laryngoscopy and Intubation Patient - coronary artery disease. Significant rises in HR (BP) could result in MI due to increased myocardial oxygen demand. Patient -unruptured cerebral or aortic aneurysm, or aortic dissection. increase in mean arterial pressure (MAP) could lead to aneurysm rupture or worsening dissection. Patients - significant preexisting hypertension, including women with pregnancy-induced hypertension. Further increases in BP could overcome the limits of cerebral autoregulation and potentially lead to increased ICP or cerebral hemorrhage  Respiratory System Response to Laryngoscopy and Intubation Coughing, laryngospasm, and bronchospasm are all potential responses to airway manipulation.  Laryngospasm may be more common in the pediatric population.  Gagging may lead to vomiting and potential aspiration.  All of these responses are more likely in the inadequately anesthetized patient and those with underlying respiratory pathology. Central Nervous System Response to Laryngoscopy and Intubation  Laryngoscopy and intubation results in a transient rise in ICP.  patients in whom ICP is already elevated or in whom cerebral autoregulation is impaired, these effects could complicate an already dangerous situation. ADJUNCTIVE AGENTS Adjunctive agents are usually given in the “pretreatment” phase of an RSI, or used to facilitate an awake intubation (or “awake look” laryngoscopy).  Midazolam Midazolam has become a popular agent for sedation in the setting of emergency airway management. used as an induction agent to facilitate RSI both in the ED and the prehospital setting In airway management, the primary role of midazolam is as a light sedative for the patient undergoing an awake intubation. also be useful in providing postintubation sedation and amnesia.  Midazolam Drug: Midazolam. Drug type: Benzodiazepine. Sedative, anxiolytic, hypnotic. Indications: Sedation, amnesia, anxiolysis, coinduction agent. Contraindications: Uncorrected shock states are relative contraindications that require a decrease in dose. Dose: Dose is 0.025–0.05 mg/kg IV for sedation, and 0.1–0.3 mg/kg IV for induction. Onset/Duration: Onset is 1–2 minutes. Clinical duration is 15–20 minutes. Potential Complications: Hypotension and apnea.  Butyrophenones  Haloperidol used for “chemical restraint,” whereby an otherwise mildly uncooperative patient may be rendered outwardly tranquil, immobile, and apparently indifferent to the surroundings. less likely to be successful in the actively uncooperative, critically ill patient in need of emergency airway management.  Haloperidol Drug: Haloperidol. Drug type: Antipsychotic/sedative. Indication: Chemical restraint. Contraindications: Hypersensitivity; Parkinson’s disease. Dose: Dose is 2–5 mg IV, repeated prn. Intramuscular (IM) dose is 5–10 mg. May be combined with midazolam or lorazepam in a ratio of 5:1 (e.g., haloperidol 5 mg/ lorazepam 1 mg). Onset/Duration: Onset is within 5 minutes (intravenous) or 20 minutes (intramuscular). Clinical duration is 1–2 hours. Potential Complications: Extrapyramidal effects; hypotension and dysrhythmias (rarely).  Opioids The term opiate refers to the group of drugs derived from opium It is important to remember that the opioids do not possess intrinsic amnestic properties, nor do they cause muscle relaxation. Blunt airway reflexes (especially the cough reflex)  Morphine  slow onset time, taking up to 15 minutes  result in histamine release,  Drop blood pressure. Morphine’s role in airway management is essentially limited to postintubation sedation and analgesia.  Morphine Drug: Morphine. Drug type: Opioid analgesic. Indication: Analgesia. Contraindications: Uncorrected shock states are relative contraindications; if used, a decrease in dose will be required. Dose: Dose is 0.05–0.1 mg/kg IV (average 75 kg = 5 mg). Onset/Duration: Onset is within 5–15 minutes. Clinical duration is 1–2 hours. Potential Complications: Hypotension and apnea. Histamine release.  Fentanyl fentanyl is generally given in the pretreatment phase, before administration of the induction sedative/hypnotic.  Fentanyl Drug: Fentanyl. Drug type: Opioid analgesic. Indication: Analgesia. Sedation. Contraindications: Uncorrected shock states are relative contraindications; if used, a decrease in dose is required. Dose: Dose is 1–3 μg/kg IV. (Average pretreatment dose 75 kg = 150 μg) Onset/Duration: Onset is less than 1 minute. Clinical duration is 1 hour. Potential complications: Apnea. Hypotension.  Lidocaine Lidocaine is the mainstay of topically- applied airway anesthesia for awake intubation in many institutions.  Lidocaine Drug: Lidocaine. Drug type: Local anesthetic. Indication: Intravenous: Historically, attenuation of pressor response or cough reflex to intubation. Applied topically, via cricothyroid injection or percutaneous nerve block: Airway anesthesia for awake intubation. Contraindications: Hypersensitivity to amidetype local anesthetics. Dose—IV use: Dose is 1–1.5 mg/kg IV (average 75 kg = 100 mg). Onset/Duration: Onset is 1–3 minutes. Duration is ~ 20 minutes. Potential Complications: Symptoms of local anesthetic toxicity. Hypotension. Seizures.  Atropine Drug: Atropine. Drug type: Anticholinergic/antimuscarinic. Indication: Bradycardia. Prophylaxis prior to repeated doses of succinylcholine or historically, pretreatment in pediatrics. Contraindications: Glaucoma is a relative contraindication, as is any situation in which tachycardia may be undesirable. Dose: Dose is.01–.02 mg/kg IV (average 75 kg = 0.5 −1 mg). Onset/Duration: Onset is within 1 minute. Clinical duration is 20–30 minutes. Potential Complications: Tachycardia. Central anticholinergic syndrome.  Induction sedative/hypnotics are used primarily to induce unconsciousness in the patient as part of an RSI.  lower doses, used as sedative agents.  use of muscle relaxants requires the concomitant use of an induction agent to ensure lack of awareness. There is some evidence suggesting that use of induction sedative/hypnotics as part of an RSI actually improves intubating conditions and decreases time needed to perform RSI.  Propofol Propofol is an intravenous sedative/hypnotic agent that works primarily via gamma amino butyric acid (GABA) receptors to produce hypnosis. Propofol has become popular because of its rapid onset and short clinical duration. Recovery from the effects of propofol is notable for the lack of residual sedation.  Propofol Drug: Propofol. Drug type: Anesthetic induction sedative/ hypnotic. Indication: Induction of unconsciousness; sedation. Contraindications: Uncorrected shock states are relative contraindications, at least requiring a significant decrease in dose. Pediatric longterm infusions are contraindicated. Dose: Induction dose is 1–3 mg/kg (average 75 kg = 150 mg). Dosage should be decreased in the elderly and volume- depleted patient. Onset/Duration: Onset is ~30 seconds. Clinical duration is 5– 15 minutes. Potential Complications: Hypotension and apnea; pain on injection.  Thiopental Thiopental is a barbiturate sedative/hypnotic, and until the introduction of propofol, it was the primary agent used for induction of general anesthesia. Despite the popularity of propofol, thiopental is still widely used in many operating rooms (ORs) and emergency departments (EDs). Thiopental is not generally used as a sedative agent to facilitate awake intubations.  Thiopental Drug: Thiopental. Drug type: Anesthetic induction agent; sedative/ hypnotic. Indication: Induction of unconsciousness. Contraindications: Uncorrected shock states are relative contraindications that require a marked decrease in dose. Dose: Dose is 3–5 mg/kg (average 75 kg = 250 mg), depending on hemodynamics. Onset/Duration: Onset is about 30 seconds. Clinical duration is 5–10 minutes. Potential complications: Hypotension and apnea.  Ketamine Ketamine is unique among the sedative/hypnotic agents in both its mechanism of action and its clinical effects. Produces a state of “dissociative amnesia,” Produces excellent amnesia and is the only induction agent to also provide analgesia.  Ketamine Drug: Ketamine. Drug type: Anesthetic induction agent, sedative/ hypnotic, analgesic. Indication: Induction of unconsciousness, especially for patients with severe bronchospasm or unstable hemodynamics. Sedative to facilitate non-RSI intubations. Contraindications: Known coronary artery disease or an elevated ICP are relative contraindications. Dose: Dose is 1–2 mg/kg IV (average 75 kg = 100 mg). Onset/Duration: Onset is within 60 seconds. Clinical duration is 15– 20 minutes. Potential Complications: Increase in heart rate (HR) and BP, with potential myocardial ischemia. Increase in ICP. Emergence reactions.  Etomidate GOLD STANDARD Stimulate a sleep like state Cardiopulmo- neutral remarkable for its hemodynamic stability. used increasingly as an alternative to propofol for sedation in the ED.  Etomidate Drug: Etomidate. Drug type: Anesthetic induction agent, sedative/hypnotic. Indication: Induction of unconsciousness, especially in patients with unstable hemodynamics. Contraindications: Known hypersensitivity. Septic shock is a relative contraindication. Dose: Dose is 0.2–0.3 mg/kg IV (average 75 kg = 20mg). Onset/Duration: Onset is within 30 seconds. Clinical duration is 5–10 minutes. Potential Complications: Hypotension and apnea. Adrenal suppression. Defasciculating Agents NEUROMUSCULAR BLOCKERS (MUSCLE RELAXANTS)  standard practice in most of the larger EDs throughout North America.  the increased success and safety with this technique.  two classes of muscle relaxant: depolarizing and nondepolarizing.  Depolarizing Muscle Relaxants: Succinylcholine  commonly used neuromuscular blocker  Multiple side effects, some of which, although extremely rare, are potentially serious.  Widespread use, for three reasons: (a) it has a very rapid onset; (b) it usually has a very short duration of action, and (c) many clinicians are familiar with its use.  Succinylcholine Drug: Succinylcholine. Drug type: Depolarizing muscle relaxant. Indication: Skeletal muscle relaxation for RSI. Contraindications: Predicted inability to either mask ventilate or intubate. Hyperkalemia. Malignant hyperthermia. Patients 24 hours or more postburn or denervation injury. Pseudocholinesterase deficiency is a relative contraindication. Dose: Dose is 1–2 mg/kg IV (average 75 kg = 120 mg). Onset/Duration: Onset is less than 1 minute.Clinical duration is 5–10 minutes. Potential Complications: Hypoxia, hypercarbia, hyperkalemic arrest, malignant hyperthermia, prolonged paralysis, myalgias. Nondepolarizing Muscle Relaxants  Rocuronium used with increasing frequency in the emergency setting as part of RSI and when indicated, for post-intubation neuromuscular blockade.  Rocuronium Drug: Rocuronium. Drug type: Nondepolarizing muscle relaxant. Indication: Skeletal muscle relaxation for RSI, or post-intubation paralysis. Contraindications: Predicted inability to either bag-mask ventilate or intubate. Dose: Dose is 1 mg/kg IV (average 75 kg = 80 mg). Onset/Duration: Onset is within 1–1.5 minutes. Clinical duration is 45–80 minutes, depending on dose administered. Potential Complications: Hypoxia, hypercarbia. Pain on injection.  Vecuronium  intermediate-acting nondepolarizing muscle relaxant.  no cardiac effects and does not stimulate histamine release.  role of vecuronium in airway management is limited largely to postintubation management.  Vecuronium Drug: Vecuronium. Drug type: Nondepolarizing muscle relaxant. Indication: Skeletal muscle relaxation postintubation. Contraindications: Predicted inability to either bag mask ventilate or intubate. Dose: Intubating dose is 0.1–0.3 mg/kg IV (average 75 kg = 8 mg initially; 2–4 mg for maintenance of post-intubation paralysis). Onset/Duration: Onset is within 1.5–3 minutes. Clinical duration is 45–90 minutes, depending on dose. Potential complications: Hypoxia, hypercarbia.  Pancuronium  long-acting nondepolarizing muscle relaxant with a relatively slow onset of action.  Clinical relaxation lasts at least an hour.  consistently causes an increase in heart rate and rarely, may result in dysrhythmias.  Considered for post-intubation paralysis if the duration of paralysis is not of concern.  Pancuronium Drug: Pancuronium Drug type: Nondepolarizing muscle relaxant. Indication: Pretreatment agent before succinylcholine administration. Skeletal muscle relaxation post-intubation. Contraindications: Predicted inability to either bag-mask ventilate or intubate. Dose: Intubating dose is 0.1 mg/kg IV (average 75 kg = 8 mg initially; 1–2 mg for maintenance of post-intubation paralysis). As a pretreatment agent before succinylcholine,.01 mg/kg (average = 0.5–1.0 mg). Onset/Duration: Onset is within 5 minutes. Clinical duration is 60–90 minutes. Potential Complications: Hypoxia, hypercarbia, tachycardia.  THANK YOU…