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Field intubation is the placement of an advanced airway or endotracheal tube (ET) by emergency medical services (EMS) personnel outside the hospital setting. Endotracheal tube intubation (ETI) has long been the standard for airway control in the prehospital setting and is the focus of this activity. While ET placement has a long history of use in the prehospital setting, its use is not without controversy. When compared to in-hospital intubation, higher failure and complication rates have brought the practice of field intubation into question. Nevertheless, there are times when airway control is paramount, and the ability to intubate a patient who has no airway control is a critical skill for prehospital providers. This procedure requires sufficient knowledge of the proper technique and indications for its use. Local protocols and medical direction should guide prehospital providers regarding their use. This activity outlines field intubation procedures in the prehospital setting and highlights the role of the prehospital provider in performing field intubations on patients who require definitive airway control in the prehospital setting. Objectives: Review the anatomy relevant for performing endotracheal tube intubation. Summarize how field intubations impact patient outcomes. Review the limitations of performing endotracheal tube intubations in the prehospital setting. Explain the importance of collaboration and communication amongst the interprofessional team to ensure appropriate training, enhance the delivery of care, and improve outcomes for patients undergoing endotracheal tube intubation in the prehospital setting. Access free multiple choice questions on this topic.

Field intubation is the placement of an advanced airway or endotracheal tube (ET) by emergency medical services (EMS) personnel outside the hospital setting. There are many techniques available to control a patient’s airway or provide rescue ventilation and oxygenation to a patient. ET intubation (ETI), nasotracheal intubation, supraglottic airway devices, continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BPAP) machines are all viable options in the right clinical situations. ETI has long been the standard for airway control in the prehospital setting and is the focus of this article.[1] While ET placement has a long history of use in the prehospital setting, its use is not without controversy.[2] When compared to in-hospital intubation, higher failure and complication rates have brought the practice of field intubation into question.[3] Nevertheless, there are times when airway control will be paramount, and the ability to intubate a patient who has no airway control is a critical skill needed for prehospital providers in the field. This procedure requires a clear understanding of the proper technique and indications for its use. Local protocols and medical direction should guide prehospital providers regarding their use.

Field intubation is the placement of an advanced airway or endotracheal tube (ET) by emergency medical services (EMS) personnel outside the hospital setting. There are many techniques available to control a patient’s airway or provide rescue ventilation and oxygenation to a patient. ET intubation (ETI), nasotracheal intubation, supraglottic airway devices, continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BPAP) machines are all viable options in the right clinical situations. ETI has long been the standard for airway control in the prehospital setting and is the focus of this article.[1] While ET placement has a long history of use in the prehospital setting, its use is not without controversy.[2] When compared to in-hospital intubation, higher failure and complication rates have brought the practice of field intubation into question.[3] Nevertheless, there are times when airway control will be paramount, and the ability to intubate a patient who has no airway control is a critical skill needed for prehospital providers in the field. This procedure requires a clear understanding of the proper technique and indications for its use. Local protocols and medical direction should guide prehospital providers regarding their use. The decision to intubate a patient should carefully be planned. The procedure can be technically challenging and lead to additional problems even in the best of circumstances. Provider competency and comfort with the procedure may also dictate whether a patient should be intubated. If a provider is unfamiliar or uncomfortable with performing field intubation, alternatives should be used if possible. Supraglottic airways and alternatives to intubation, such as continuing to provide ventilatory support via a bag-valve-mask (BVM) with airway adjuncts or CPAP and BPAP machines, might be better and safer alternatives in certain situations. The use of supraglottic airways, airway adjuncts, and CPAP/BPAP are discussed in separate articles and are not addressed here. There will be minor variances in technique and equipment used in-field intubation depending on provider competency and local protocols, but the main concepts should apply across all EMS jurisdictions. Field intubation should be used in patients that have lost control or have an impending loss of their airway, or patients that require increased ventilatory support that cannot be maintained through BVM ventilation and the use of airway adjuncts. Training and practice, appropriate patient evaluation and selection, and preparation in advance of difficult airway situations are all critical to the success of field intubation.

The decision to intubate a patient should carefully be planned. The procedure can be technically challenging and lead to additional problems even in the best of circumstances. Provider competency and comfort with the procedure may also dictate whether a patient should be intubated. If a provider is unfamiliar or uncomfortable with performing field intubation, alternatives should be used if possible. Supraglottic airways and alternatives to intubation, such as continuing to provide ventilatory support via a bag-valve-mask (BVM) with airway adjuncts or CPAP and BPAP machines, might be better and safer alternatives in certain situations. The use of supraglottic airways, airway adjuncts, and CPAP/BPAP are discussed in separate articles and are not addressed here. There will be minor variances in technique and equipment used in-field intubation depending on provider competency and local protocols, but the main concepts should apply across all EMS jurisdictions. Field intubation should be used in patients that have lost control or have an impending loss of their airway, or patients that require increased ventilatory support that cannot be maintained through BVM ventilation and the use of airway adjuncts. Training and practice, appropriate patient evaluation and selection, and preparation in advance of difficult airway situations are all critical to the success of field intubation. Despite a long history of prehospital airway management, there is conflicting evidence to show morbidity or mortality benefit when using prehospital intubation.[3] Much of the published research has focused on the success rates and complication rates of the procedure.  While it is crucial to continue to track prehospital personnel performing field intubation, future studies should also strive to identify emerging techniques, technology, and training methods to improve outcomes.

Although field intubation has been part of a prehospital provider’s scope of practice for some time, there persists a higher complication rate with prehospital intubation than in the in-hospital setting.  The most catastrophic of these complications are the result of misplaced ET tubes, which can lead to hypoxia and a patient's death.  Misplaced endotracheal tubes were found to occur 25% of the time in a study by Katz and Falk in a cohort of 108 field intubations.[15] This misplacement rate is markedly higher than other studies examining the frequency of tube misplacement cited by the authors (0.4% to 12%), but the actual rate may be higher than previously anticipated.[15] Most of the published studies are retrospective and rely on reported and recorded complications.  Studies such as these are limited by a self-reporting bias that can lead to fewer incidents secondary to a decreased likelihood to report errors by the providers. Additionally, small sample sizes may skew the results in these studies. Katz and Falk found that the majority of misplaced tubes located in the esophagus, 67%, with the rest in the hypopharynx, 33%. Wang et al. examined the prevalence of ET intubation errors over a much larger subset of patient encounters involving intubation attempts - 1,953 patients over 18 months.[10] This study utilized an anonymous data entry system and found an overall tube misplacement rate of 3.1%.[10] Total intubation errors (including tube misplacement, four or more attempts to intubate the patient, and failed intubation) occur at a rate of 22%.[10] Although this study attempted to limit the possible under-reporting of field intubation complications by using an anonymous reporting system, the authors recognize that this bias is likely still present and feel their findings likely represent only a “best-case scenario” of field intubation error rates (Wang HA).While a misplaced tube is the most feared and devastating complication, multiple other complications can occur. There are no large studies on the rate of many of these complications in the prehospital setting, but it is expected to see similar complications to those found in the hospital setting.  These complications may include : Dental injury Vocal cord injury Laryngeal injury Tracheal injury False passage creation Vomiting Aspiration Pneumonia Barotrauma Autonomic instability Hypoxia

Although field intubation has been part of a prehospital provider’s scope of practice for some time, there persists a higher complication rate with prehospital intubation than in the in-hospital setting.  The most catastrophic of these complications are the result of misplaced ET tubes, which can lead to hypoxia and a patient's death.  Misplaced endotracheal tubes were found to occur 25% of the time in a study by Katz and Falk in a cohort of 108 field intubations.[15] This misplacement rate is markedly higher than other studies examining the frequency of tube misplacement cited by the authors (0.4% to 12%), but the actual rate may be higher than previously anticipated.[15] Most of the published studies are retrospective and rely on reported and recorded complications.  Studies such as these are limited by a self-reporting bias that can lead to fewer incidents secondary to a decreased likelihood to report errors by the providers. Additionally, small sample sizes may skew the results in these studies. Katz and Falk found that the majority of misplaced tubes located in the esophagus, 67%, with the rest in the hypopharynx, 33%. Wang et al. examined the prevalence of ET intubation errors over a much larger subset of patient encounters involving intubation attempts - 1,953 patients over 18 months.[10] This study utilized an anonymous data entry system and found an overall tube misplacement rate of 3.1%.[10] Total intubation errors (including tube misplacement, four or more attempts to intubate the patient, and failed intubation) occur at a rate of 22%.[10] Although this study attempted to limit the possible under-reporting of field intubation complications by using an anonymous reporting system, the authors recognize that this bias is likely still present and feel their findings likely represent only a “best-case scenario” of field intubation error rates (Wang HA).While a misplaced tube is the most feared and devastating complication, multiple other complications can occur. There are no large studies on the rate of many of these complications in the prehospital setting, but it is expected to see similar complications to those found in the hospital setting.  These complications may include : Dental injury Vocal cord injury Laryngeal injury Tracheal injury False passage creation Vomiting Aspiration Pneumonia Barotrauma Autonomic instability Hypoxia Special note should be made of complications that can arise in the peri- and post-intubation phases of the procedure.  Dunford et al. examined a subset of patients from the San Diego Rapid Sequence Intubation Trial, which looked at the incidence of transient hypoxia and pulse rate reactivity during field intubations.[8] This study sought to identify the rate of two complications, hypoxia and bradycardia, which can be significant detriments to good outcomes in patients with traumatic brain injuries such as those studied in the trial.  It was found that over 57% of patients experienced transient hypoxia with an SPO2 < 90% for a median duration of 180 seconds. These periods of hypoxia were accompanied by marked bradycardia, the second sign of decompensation, in 19% of intubations.  The estimated rate of transient hypoxia varied in other studies, ranging from 10% to 27%, much lower than what was found by Dunford et al.[8] These complications occurred despite standardized training on preoxygenation and RSI for all paramedics in the trial, and paramedics reporting that 84% of the patients who desaturated as being “easy” to intubate.  The subset of patients examined by Dunford et al. were all treated by the same EMS company. This higher than average rate of hypoxia episodes shows that possible systemic issues could propagate problems when performing procedures.  Because of these findings, the authors stressed that additional examination of their prescribed protocols for preoxygenation needed to be performed to find the root causes of the above-average complication rate.[8] Reexamination of protocols in the face of concerning trends is a crucial step for quality improvement within an EMS system and should be completed continuously to identify areas for improvement.Many post-intubation complications have been attributed to improper ventilation. Field intubation is a high-stress procedure.  Often providers will be highly energized with adrenalin and singularly focused on the task at hand, resuscitation. In these high-stress periods, providers may over-aggressively ventilate the patient with rapid rescue breathing via a resuscitator bag.  Davis et al. performed several studies examining the rate of hyperventilation and hypocarbia post field intubations in patients with traumatic brain injury and their corresponding effect on mortality.[6][7] The authors found that severe hyperventilation, defined as ETCO2 of less than 25 mmHg, led to a significantly higher mortality rate in their patient population than that which would be explained by injury patterns.  This inadvertent hyperventilation was found to occur in 13.4% of patients. This number decreased to 5.6% in a similar subset of patients when ETCO2 monitors were used to monitor the ventilations. It is believed that the hyperventilation of the patients in the study caused a reduction in cerebral perfusion, again a significant detriment to good outcomes in patients with traumatic brain injury.[6][7]Aggressive resuscitative ventilation can also lead to increased airway pressures and barotrauma.  This is especially true in pediatric patients who will not require a full squeeze of the resuscitation bag to receive an adequate tidal volume. It is best to try to remain calm, count out the time between breaths to once every 6 seconds or more, monitor effective ventilation with waveform capnography, and only provide a tidal volume to see the chest of the patient rise.

When examining the efficacy of field intubation, it is important to recognize that these procedures are not performed in a controlled environment of the ED or OR. The use of prehospital airway control is reserved for the “sickest of the sick” patients, with no other intervention available to bridge the patient until definitive treatment is obtained at a hospital facility. Based on the environmental and resource limitations providers face in the field, it may be unreasonable to expect field intubation success rates to equal those of in-hospital care, but this should not deter further examination and quality improvement measures. The focus of future studies should not only examine overall trends for the success rate of field intubations but also explore how this procedure can be made safer and identify which patients would benefit from the intervention. There should be a conscious effort, like those proposed by Carlson et al., to identify the latest improvements in training methods, equipment, monitoring, and techniques that are proven to show benefit to patient outcomes.[21] These findings should be incorporated into local protocols and training regimes. While national organizations and government oversight can help provide some direction and recommendations, the fragmented nature of EMS oversight sets the onus on the medical directors, medical oversight personnel of EMS companies, and the prehospital providers themselves to implement the necessary changes.