Conventional Versus Video Laryngoscopy for Tracheal Tube Exchange: Glottic Visualization, Success Rates, Complications, and Rescue Alternatives in the High-Risk Difficult Airway Patient.

BACKGROUND: Tracheal tube exchange is a simple concept but not a simple procedure because hypoxemia, esophageal intubation, and loss of airway may occur with life-threatening ramifications. Combining laryngoscopy with an airway exchange catheter (AEC) may lessen the exchange risk. Laryngoscopy is useful for a pre-exchange examination and to open a pathway for endotracheal tube (ETT) passage. Direct laryngoscopy (DL) is hampered by a restricted "line of sight"; thus, airway assessment and exchange may proceed blindly and contribute to difficulty and complications. We hypothesized that video laryngoscopy (VL), when compared with DL, will improve glottic viewing for airway assessment, and the VL-AEC method of ETT exchange will result in a reduction in airway and hemodynamic complications in high-risk patients when compared with a historical group of patients who underwent DL + AEC-assisted exchange. METHODS: Critically ill patients requiring an ETT exchange underwent DL-assisted pre-exchange airway assessment. If the DL-assisted pre-exchange assessment rendered a "poor view," these patients underwent a VL-based airway assessment followed by a VL-assisted ETT exchange procedure. The DL and VL pre-exchange assessments were compared. The attempts, complications, and rescue devices required for ETT exchange were analyzed. These exchange results were then compared with a historical control group of patients who (1) were classified as a poor view on DL-assisted pre-exchange airway assessment; and (2) underwent a DL + AEC-assisted exchange. The airway assessment and ETT exchange were performed by a board-certified anesthesiologist from the Department of Anesthesiology alone or with anesthesia resident assistance. RESULTS: Three hundred twenty-eight patients with a poor view on initial DL examination underwent a subsequent VL with comparison of views with the 337 patients in the historical control group (DL + AEC). A majority (88%) had a "full or near-full view" on VL examination. The first-pass success rate for ETT exchange was greater in the VL group (91.5% vs 67.7% with DL; P = 0.0001) and the number of patients requiring 3+ attempts was lower (1.2% vs 6.8% with DL; P = 0.0003). A commensurate difference in the incidence of mild and severe hypoxemia, esophageal intubation, bradycardia, and the need for rescue airway device intervention was also observed with VL exchange procedures when compared with the historical DL + AEC group. CONCLUSIONS: These findings support the hypothesis that VL may result in better glottic viewing for airway assessment and may permit the ETT exchange procedure to be performed with fewer airway and hemodynamic complications. Execution of the ETT exchange over an AEC was augmented by improved glottic visualization to allow more efficient and timely ETT passage. Multiple attempts to resecure the airway increased the number of exchange complications. VL + AEC exchange led to fewer attempts and is consistent with the recommendation of the American Society of Anesthesiologists Difficult Airway Task Force to limit laryngoscopic attempts and, as a consequence, decrease complications. A VL-based pre-exchange airway assessment may be a valuable procedure for both planning the exchange and uncovering unrecognized airway maladies, for example, partial or complete self-extubation.

Video laryngoscopy improves intubation success and reduces esophageal intubations compared with direct laryngoscopy in the medical intensive care unit.

Urgent and emergent airway management outside the operating room is fraught with complications due to the nature of its acuity, single or multiple system dysfunction or failure, and physiological disturbances. These provide a challenge to the airway team and place the patient at grave risk for potentially life-threatening airway and hemodynamics-related consequences. Conventional laryngoscopy is rapidly being challenged by video-camera-assisted laryngoscopes that, in many cases, offer improved visualization of the airway. Successful intubation remains a lofty but attainable goal for airway specialists as well as the novice intubator. Yet to assume that airway management difficulties can be erased by incorporating a new device is optimistic but naïve. In regard to patient safety, the device is just one piece of the airway puzzle.

Airway management issues in the intensive care unit: revisiting old paradigms and broadening our horizons.

Airway management in the intensive care setting provides unique challenges that can be quite daunting, even for the most experienced practitioner. Airways are usually intubated for long periods, multiple comorbidities often interfere with "routine" airway management practices, and patients are often physiologically disadvantaged or hemodynamically unstable. Strapped with this calamity, the first responder to a patient with an acutely compromised airway is often someone less experienced with global airway management skills. As anesthesiologists, we are very familiar with the skill sets necessary to handle these predicaments, and as intensivists, we have the fortunate opportunity to share that wealth of information and experience. Airway care in the intensive care unit is a continuum-from elective or emergent intubation, to airway preservation and hygiene, to elective or unintentional extubation. Thus, familiarization with the basics of airway management in routine and "first responder" settings should bolster confidence and greatly improve patient safety and outcomes.

Extending the preoxygenation period from 4 to 8 mins in critically ill patients undergoing emergency intubation.

OBJECTIVE: To determine the effectiveness of increasing the preoxygenation period with 100% oxygen in the critically ill patient from 4 to 8 mins in preparation for emergency tracheal intubation. DESIGN: Nonrandomized, controlled trial. SETTING: Large, level one trauma center, tertiary care intensive care unit. PATIENTS: Critically ill patients failing noninvasive respiratory support techniques who required tracheal intubation followed by mechanical ventilation. INTERVENTIONS: A baseline arterial blood gas was obtained on noninvasive passive therapy and at 4, 6, and 8 mins of active preoxygenation efforts with 100% oxygen therapy with a noncollapsing resuscitator bag and mask. Best effort to achieve a tight fitting mask seal was pursued coupled with other mask ventilation maneuvers to optimize noninvasive oxygenation and ventilation. MEASUREMENTS AND MAIN RESULTS: Thirty-four patients consecutively intubated by the author during the 7-month study period were studied. The baseline PaO2 (mean +/- SD) with concurrent noninvasive support was 61.9 +/- 14.6 mm Hg (range: 44-109 mm Hg) and increased a mean of 22 mm Hg to 83.8 +/- 51.5 mm Hg after 4 mins of preoxygenation (p < 0.01). Continued preoxygenation efforts (6 mins) increased the PaO2 to 88.2 mm Hg +/- 48.5 and after 8 mins to 92.7 mm Hg +/- 55.2. At the 8-min mark, 5 of 34 patients achieved > 10% increase in their PaO2 and only two patients increased their 4-min PaO2 by > or = 50 mm Hg after the additional 4 mins of preoxygenation. One quarter of the patients experienced a reduction in their PaO2 from the 4 to the 8-min time period. Nearly, 50% of the patients met the criteria for desaturation during the intubation procedure. CONCLUSIONS: Extending the preoxygenation period from the customary 4 mins to either 6 or 8 min seems to be marginally effective in the majority of patient suffering from cardiopulmonary deterioration and such an extension may jeopardize oxygenation efforts in some patients.

Tracheal tube exchange: feasibility of continuous glottic viewing with advanced laryngoscopy assistance.

Trachea tube exchange via an airway exchange catheter is commonly combined with conventional laryngoscopy to assist intubation of the trachea. Glottic visualization may not be possible in the difficult airway. A delay in reintubation, airway injury, or intubation failure may complicate "blind" tracheal intubation because of excessive endotracheal tube size or tip impingement on airway structures. Advanced laryngoscopic techniques offering "around the corner" visualization may overcome many of the limitations of conventional laryngoscopy's "line of sight." In this data review, I examined the feasibility and usefulness of transforming a high-risk exchange from a blind procedure into one with improved glottic visualization.

Continuous airway access for the difficult extubation: the efficacy of the airway exchange catheter.

BACKGROUND: The American Society of Anesthesiologists Task Force on the Management of the Difficult Airway regards the concept of an extubation strategy as a logical extension of the intubation process, although the literature does not provide a sufficient basis for evaluating the merits of an extubation strategy. Use of an airway exchange catheter (AEC) to maintain access to the airway has been reported on only a limited basis. METHODS: I reviewed an observational analysis of a prospectively collected difficult airway quality improvement database for patients who were extubated over an AEC for a known or presumed difficult airway primarily in the intensive care unit. The data were reviewed for time to reintubation, number of attempts to reintubate the trachea, method of securing the airway, incidence of hypoxemia during reintubation, and complications encountered during reestablishment of the airway. RESULTS: Fifty-one patients with an indwelling AEC failed their extubation trial. Forty-seven of 51 AEC patients were successfully reintubated over the AEC (92%), with 41 of 47 on the first attempt (87%). In three of the four AEC reintubation failures, the AEC was inadvertently removed from the glottis during the reintubation process, and one patient had significant laryngeal edema precluding endotracheal tube advancement. CONCLUSIONS: Maintaining continuous access to the airway postextubation via an AEC can be an important component of an extubation strategy in selected difficult airway patients. The indwelling AEC appears to increase the first-pass success rate in patients with known or suspected difficult airways and decrease the incidence of complications in patients intolerant of extubation and requiring tracheal reintubation.

Laryngeal mask airway and bougie intubation failures: the Combitube as a secondary rescue device for in-hospital emergency airway management.

When conventional intubation methods fail, an accessory rescue airway device must be immediately available and rapidly deployed to assist the clinician in managing the airway. I reviewed an emergency intubation database to determine what airway devices were used as a backup to rescue the primary rescue device failures. The bougie and the laryngeal mask airway each have an intrinsic failure rate. The Combitube(R), commonly used in the emergency prehospital setting, appeared to be a useful secondary rescue device in the hospital setting when the bougie and laryngeal mask airway failed.

Esophageal intubation with indirect clinical tests during emergency tracheal intubation: a report on patient morbidity.

STUDY OBJECTIVE: To determine the consequences of esophageal intubation (EI) when using standard indirect clinical tests to detect endotracheal tube (ETT) placement in the emergency setting outside the operating room (OR). DESIGN: An observationally based review of a quality improvement database for emergency intubation outside the OR. SETTING: Seven hundred sixty-five-bed tertiary care, level I trauma center in central Connecticut. PATIENTS: Critically ill patients (n = 2377) experiencing cardiopulmonary, traumatic, septic, metabolic, or neurologic-based deterioration and requiring emergency airway management. Tracheal intubation of patients with cardiopulmonary resuscitation and chest compressions were excluded. MEASUREMENTS: A quality improvement emergency intubation database from 1990 to 2001 was reviewed to determine the incidence of EI and its associated complications (mild and severe hypoxemia, regurgitation, aspiration, hemodynamic alteration, cardiac dysrhythmias, and cardiac arrest) when ETT position is determined by standard indirect clinical tests without the benefit of ETT-verifying devices. RESULTS: Patients who had EI, in contrast to those who did not, had significant rates of hypoxemia (64.7% vs 13.1%; P < .001) and severe hypoxemia (Spo2 < 70%) (25% vs 4.4%; P < .001). The rate of regurgitation (24.7% vs 2.4%) and aspiration (12.8% vs 0.8%) also differed significantly (P < .001). The overall incidence of bradycardia, typically hypoxia-driven, was more common (14-fold) after EI (21.3% vs 1.5%), as was new onset cardiac dysrhythmia (6-fold increase, 23.4% vs 4.1%) and cardiac arrest (14-fold increase, 10.2% vs 0.7%), all P < .001. CONCLUSION: These data suggest that EI during emergency intubation, when detected by standard indirect clinical tests based on physical examination, contributes significantly to mild and severe hypoxemia, regurgitation, aspiration, bradycardia, cardiac dysrhythmias, and cardiac arrest. Pursuing methods to hasten the detection of EI in the emergency setting appear warranted.

The incidence and risk factors for cardiac arrest during emergency tracheal intubation: a justification for incorporating the ASA Guidelines in the remote location.

STUDY OBJECTIVE: To determine the incidence and etiology of cardiopulmonary arrest during emergency intubation in the remote location by comparing two periods (1990-1995 vs. 1995-2002) at the same institution to assess whether immediate access to advanced airway devices and endotracheal tube-verifying devices altered the incidence of hypoxemia-driven cardiac arrest. DESIGN: Retrospective review of a quality improvement (QI) database for emergency intubation outside the operating room (OR). SETTING: 765-bed tertiary care, level 1 trauma center. PATIENTS: 3035 critically ill patients suffering from cardiopulmonary, traumatic, septic, metabolic, or neurological-based deterioration and requiring emergency airway management. MEASUREMENTS: Rate of cardiac arrest, as defined as asystole, bradycardia, or ventricular dysrhythmia with non-measurable blood pressure during or within 5 minutes of intubation, requiring cardiopulmonary resuscitation (CPR), were measured. MAIN RESULTS: 60 cardiac arrests were documented (2%, or one per 50 cases), 83% of which were associated with profound hypoxemia (oxygen saturation <70%) during the airway procedure. Esophageal intubation was a frequent complication (n = 38; 63%), often leading to hypoxemia (97%) and regurgitation (67%). The overall rate of cardiac arrest was reduced 50% between the two time periods (2.8%: 1990-1995 period and 1.4%: 1995-2002 period). The relative risk estimate for complications in a match cohort contributing to the etiology of cardiac arrest included hypoxemia (4X), regurgitation (28X), aspiration (22X), bradycardia (23X) (all P < 0.003), and esophageal intubation (7X), P < 0.04). A total of 34% patients survived less than 24 hours and 31% survived to be discharged. CONCLUSION: Cardiac arrest during emergency tracheal intubation outside the OR is relatively common compared with the OR environment. Airway-related complications played a prominent role, either singly or in combination with the patient's underlying physiological state. Immediate access to advanced airway devices and endotracheal tube-verifying devices appear to have a significant impact on the incidence of hypoxemia-driven cardiac arrest.

Complications of emergency tracheal intubation: immediate airway-related consequences: part II.

Airway management in the stable, elective operating room patient is typically exceptionally safe. Conversely, the acute deterioration of an intensive care unit or floor patient being rescued by a clinician unfamiliar with the patient's past and current history combined with an incomplete physical examination places the critically ill patient in a precarious, potentially life-threatening position. Emergency airway management in remote locations outside the confines of the operating room is complex and stressful due to immense airway challenges coupled with the high risk of hemodynamic and airway complications. Despite the commonality of difficulties with mask ventilation, laryngoscopy, and tracheal intubation in this population, relatively sparse literature deals with these subjects. Consequences of airway management should be openly discussed as a first step toward improving airway safety. This is the second of 2 reviews, "Complications of Emergency Tracheal Intubation," and focuses on the immediate airway-related consequences during emergency tracheal intubation in the remote location.

Complications of emergency tracheal intubation: hemodynamic alterations--part I.

Emergency airway management outside the elective operating room presents considerable risks to the patient and significant challenges to the practitioner. Complications and adverse consequences are commonplace, yet they have not received their justified discussion or scrutiny in the literature. This review will discuss potentially life-threatening complications partitioned into 2 broad categories: hemodynamic and airway. Part 1 will focus on alterations in the heart rate and blood pressure, new onset cardiac dysrhythmias and cardiac arrest. Part 2 will explore airway related consequences such as hypoxemia, esophageal intubation, multiple intubation attempts, and aspiration.

Anesthesia practice in the emergency department: overview, with a focus on airway management.

PURPOSE OF REVIEW: To review the need for interdisciplinary collaboration to reduce human and system-related errors in the emergency care setting. RECENT FINDINGS: The complexities of airway management are immense and though great strides have been made to improve patient safety, patient injury continues. Airway management is being provided by several specialties who claim responsibility and expertise, sometimes at the exclusion of other specialties. Collaboration among specialties is needed to foster a healthy working relationship as synergism of each department's aptitude and talents may contribute to patient safety. To collaborate effectively with the goal of developing an executable action plan, we must first understand the underlying causation of errors based on human and system-related failures inherent in the medical system. A proactive approach to address these deficiencies is imperative towards improving nearly any aspect of patient care; however, this review will focus specifically on airway management issues in the emergency department. SUMMARY: The implications of collaboration are sweeping; not only for optimizing patient care but leading to a 'win-win' situation for medical personnel by improving relationships to better address global needs and optimize the opportunities for collaboration, which is particularly true for urgent/emergent airway management.

Preoxygenation in critically ill patients requiring emergency tracheal intubation.

OBJECTIVE: To determine the effectiveness of preoxygenation with 100% oxygen in the critically ill patient in preparation for emergency tracheal intubation. DESIGN: Nonrandomized, controlled trial. SETTING: Large, level 1 trauma center, tertiary care intensive care unit. PATIENTS: Critically ill patients failing noninvasive respiratory support techniques who require tracheal intubation followed by mechanical ventilation. INTERVENTIONS: A baseline arterial blood gas was obtained on noninvasive therapy and 4 mins post-100% oxygen therapy with a bag-mask assembly. Best effort to achieve a tight-fitting mask seal was pursued coupled with other mask ventilation maneuvers to optimize noninvasive oxygenation and ventilation. MEASUREMENTS AND MAIN RESULTS: A total of 42 patients consecutively intubated during the 15-month study period were studied. The baseline Pao2 (mean +/- sd) with concurrent noninvasive support was 67 +/- 19.6 mm Hg (range, 43-88 mm Hg) and increased a mean of 37 mm Hg to 103.8 +/- 63.2 mm Hg after 4 mins of preoxygenation with 100% oxygen. A total of 36% of patients had minimal changes (+/-5%) in their baseline Pao2, and only 19% increased their baseline Pao2 by at least 50 mm Hg after preoxygenation maneuvers. CONCLUSIONS: The critically ill patient has little reserve to tolerate interruption of oxygen delivery and, thus, is at risk for hypoxemia during emergency airway management. Preoxygenation efforts as described in this clinical trial appear to be marginally effective in regard to providing a reasonable safeguard against hypoxemia during laryngoscopy and endotracheal intubation.

Emergency tracheal intubation: complications associated with repeated laryngoscopic attempts.

Repeated conventional tracheal intubation attempts may contribute to patient morbidity. Critically-ill patients (n = 2833) suffering from cardiovascular, pulmonary, metabolic, neurologic, or trauma-related deterioration were entered into an emergency intubation quality improvement database. This practice analysis was evaluated for airway and hemodynamic-related complications based on a set of defined variables that were correlated to the number of attempts required to successfully intubate the trachea outside the operating room. There was a significant increase in the rate of airway-related complications as the number of laryngoscopic attempts increased (2 attempts): hypoxemia (11.8% versus 70%), regurgitation of gastric contents (1.9% versus 22%), aspiration of gastric contents (0.8% versus 13%) bradycardia (1.6% versus 21%), and cardiac arrest (0.7% versus 11%; P < 0.001). Although predictable, this analysis provides data that confirm the number of laryngoscopic attempts is associated with the incidence of airway and hemodynamic adverse events. These data support the recommendation of the ASA Task Force on the Management of the Difficult Airway to limit laryngoscopic attempts to three in lieu of the considerable patient injury that may occur.