Society of Critical Care Medicine Clinical Practice Guidelines for Rapid Sequence Intubation in the Critically Ill Adult Patient: Executive Summary

Controversies and practice variations exist related to pharmacologic and nonpharmacologic emergency airway management during rapid sequence intubation (RSI) (1,2). Therefore, the American College of Critical Care Medicine (ACCM)'s Board of Regents established a guideline panel to review this topic and provide current, systematically developed recommendations to guide clinical practice. Emergency airway management is complex and involves decision-making around devices chosen for laryngoscopy, medications used to facilitate intubation, and management after intubation. A common strategy for emergency airway management is RSI, which is defined as the administration of a sedative-hypnotic agent and a fast-acting neuromuscular-blocking agent (NMBA) in rapid succession along with the placement of an endotracheal tube (3,4). RSI is indicated to: 1) reduce the risk of aspiration in at-risk patients (e.g., those with a full stomach, ileus or bowel obstruction, gastroesophageal reflux disease, and increased intraabdominal pressure) and 2) optimize intubating conditions to reduce the occurrence rate of difficult or failed airways, esophageal tube placement, and complications. For the purposes of these guidelines, we considered aspects directly related to RSI as pertinent, such as those that occur in the preoxygenation period before RSI and medication selection during RSI. For example, mask ventilation has historically been avoided with RSI to reduce the risk of regurgitation and aspiration of gastric contents, but mask ventilation may reduce the risk of critical hypoxemia. Common themes with conflicting opinions are 1) whether an induction agent should be used and 2) whether an NMBA should be used for emergency airway management in all critically ill patients. We addressed this with two questions involving the use of only one pharmacologic agent (either a sedative-hypnotic induction agent or an NMBA) even though such a recommendation would deviate from the definition of RSI. Awake intubations, difficult airway management, postintubation sedation, and ventilator management are outside the scope of work for these guidelines. METHODS Society of Critical Care Medicine (SCCM) organized a multidisciplinary panel of 20 practitioners that included pharmacists, physicians, a nurse practitioner, and a respiratory therapist with expertise in emergency medicine, critical care medicine, anesthesiology, and prehospital medicine from the United States and Australia. Panel members had various backgrounds related to RSI-themed research, clinical practice, society leadership, and previous guideline development. Methodological support from a clinician with Grading of Recommendation, Assessment, Development, and Evaluations (GRADE) experience and a librarian were available. GRADE methodology was followed for practice management guideline development (3). Panelists met via teleconference and face-to-face meetings and communicated via e-mail to develop Population, Intervention, Comparison, and Outcome (PICO) questions that addressed the aforementioned practice variability, examined evidence, and developed these practice guidelines. Each panelist followed all conflict-of-interest procedures as documented in the SCCM Standard Operating Procedures Manual. This activity was funded by SCCM, and no industry support was provided. Panelists identified topic areas of interest or controversy relevant to RSI in critically ill adults and submitted 35 potential PICO questions for consideration. Panelists voted on PICO questions for inclusion based on clinical relevance. The highest-scoring PICO questions were selected for literature evaluation and the final wording was refined. Using GRADE methodology that included a literature search, evidence evaluation, evidence-to-decision framework, and consensus meetings, panelists voted on the statements issued in this guideline (3). "Recommendations" were developed when evidence was actionable; "suggestions," when evidence was equivocal; and "best practice statements," when the benefits of the intervention outweighed the risks, but direct evidence to support the intervention did not exist as per GRADE methodology. Methodology related to guideline development can be accessed in Supplemental Digital Content (https://links.lww.com/CCM/H378). RESULTS This clinical practice guideline provides guidance with rationales for one recommendation, seven suggestions, and two best practice statements developed from 10 PICO questions related to RSI in critically ill adults. In one instance, a single PICO produced two suggestions. In another instance, there was no recommendation associated with a PICO question due to insufficient evidence. Since the goal of the "Executive Summary" is to focus on a few key recommendations, an abbreviated rationale for the one recommendation and four suggestions are included. These statements were chosen based on the strength of the recommendation (Strong or Conditional) along with the highest quality of evidence (Moderate or Low) and are ordered as such in the Executive Summary. All guideline recommendations, suggestions, and best practice statements (11 statements total) along with complete rationales can be found in the main article published in Critical Care Medicine (4). Evidence profiles and a summary of judgments are available in Supplemental Digital Content (https://links.lww.com/CCM/H378). These guidelines are intended for clinicians who treat critically ill adult patients in the emergency department, ICU, or other locations outside the operating room who require emergency airway management with endotracheal intubation using RSI. SELECT GRADE RECOMMENDATIONS Question: In critically ill adults undergoing endotracheal intubation, is there a difference between the administration of a sedative-hypnotic agent with an NMBA versus a sedative-hypnotic agent alone with respect to first-pass intubation success (FPS), the incidence of respiratory arrest or cardiovascular collapse, need for a surgical airway, or incidence of vomiting/aspiration during the peri-intubation period? Recommendation: We recommend administering an NMBA when a sedative-hypnotic induction agent is used for intubation (strong recommendation, low quality of evidence). Rationale: Five studies were evaluated that demonstrated favorable FPS when an NMBA was administered for RSI compared with when an NMBA was not. Also, the occurrence of respiratory arrest or cardiovascular collapse and vomiting/aspiration was less in those that received an NMBA compared with those that did not. Given the widespread availability and low cost of NMBAs, these agents should be used for airway management in critically ill patients when an induction agent is planned with the goal of inducing unconsciousness. Question: In critically ill adults undergoing RSI, is there a difference between etomidate versus other induction agents (e.g., ketamine, midazolam, propofol) with respect to mortality or the incidence of hypotension or vasopressor use in the peri-intubation period and through hospital discharge? Recommendation: We suggest there is no difference between etomidate and other induction agents administered for RSI with respect to mortality or the incidence of hypotension or vasopressor use in the peri-intubation period and through hospital discharge. (Conditional recommendation, moderate quality of evidence). Rationale: There are concerns about the development of adrenal insufficiency following the administration of etomidate as an induction agent for RSI. However, we found no evidence to suggest a difference in mortality comparing etomidate to other induction agents (e.g., ketamine, midazolam, propofol). There were mixed results regarding peri-intubation hemodynamics with etomidate and ketamine; however, the clinical impact of these hemodynamic changes was not elucidated in the studies evaluated. There was no difference in the need for, or duration of use of, vasopressors when etomidate was used compared with other induction agents. Question: In critically ill adults undergoing planned RSI, is there a difference between preoxygenation with high-flow nasal oxygen (HFNO) (with or without apneic oxygenation) versus using face-mask preoxygenation, bag-mask ventilation, or noninvasive positive pressure ventilation (NIPPV) with respect to the occurrence of desaturation, gastric insufflation, or pulmonary aspiration risk? Recommendation: We suggest preoxygenation with HFNO when laryngoscopy is expected to be challenging (conditional recommendation, low quality of evidence). Recommendation: We suggest preoxygenation with NIPPV in patients with severe hypoxemia Pao2/Fio2 of less than 150 (conditional recommendation, low quality of evidence). Rationale: A total of 13 studies were evaluated; eight studies reported oxygen desaturations of less than 80% and nine studies evaluated desaturation as an outcome with most evaluating the lowest oxygen saturation. Studies with the outcomes of desaturation had higher quality data, but there was substantial heterogeneity in the patient populations that were included and in the severity of hypoxemia. Although the oxygen saturation cutoffs were arbitrary, HFNO appeared to reduce desaturation rates, prolong safe apnea times, and limit the degree of desaturation compared to studies of preoxygenation with a face mask, but not necessarily compared with studies in which NIPPV was used. In patients with a difficult airway, providing continuous HFNO has a potential benefit versus the comparators, which may obviate the risks associated with apnea, especially if prolonged, and allow for a longer safe apnea before critical desaturation occurs. Also, HFNO did not seem to lead to gastric insufflation and increased aspiration risk. However, in patients with severe hypoxemia that need to be escalated to a noninvasive support modality for preoxygenation, NIPPV appears to have the strongest evidence for decreasing the incidence of critical desaturation during RSI. Question: In critically ill adults undergoing RSI, is there a difference between rocuronium versus succinylcholine when used for RSI with respect to mortality, FPS, adverse events, and risk of awareness in the peri-intubation period and through hospital discharge? Recommendation: We suggest administering either rocuronium or succinylcholine for RSI when there are no known contraindications to succinylcholine (conditional recommendation, low quality of evidence). Rationale: Only one observational study evaluated the outcome of mortality (5). This was conducted in a subset of patients with traumatic brain injury as it is suggested that succinylcholine may be associated with a transient increase in intracranial pressure. Although this study reported patients with a high-severity head injury had a greater risk of mortality when succinylcholine was used for intubation, it was limited by retrospective design and potential for selection bias. A large number of studies evaluated adverse events between these two NMBAs, but there was serious heterogeneity and indirectness across the studies. Studies measured different types of adverse events and most had small sample sizes and were inadequately powered to find significant differences in safety outcomes. Furthermore, there was no difference in FPS rate or patient awareness reported in the body of literature. The evidence did highlight that rocuronium use may delay the provision of postintubation analgosedation compared to when succinylcholine is used. This likely occurs because the patient is not eliciting a response that would warrant action during the period of prolonged paralysis. Protocolized care and incorporation of personnel, such as clinical pharmacists, should be considered to improve the timeliness of analgosedation implemented. CONCLUSIONS As a multidisciplinary group of clinicians with experience in airway management appointed by ACCM, we aimed to incorporate the most recent and best evidence available at the time of writing to improve the care of critically ill adults undergoing RSI. The recommendations provided are not absolute requirements and should be tailored to individual patients and with available equipment and resources, as appropriate. Particular patient populations, resources, and feasibility were considered and factored into our deliberations and recommendations. The release of data from ongoing studies and future research may result in focused updates. Until such time, guideline application by clinicians should always be modified based on new evidence, as it becomes available.