Emergency tracheal intubation immediately following traumatic injury: An Eastern Association for the Surgery of Trauma practice management guideline

Testing of novel spectral device sensor in swine model of airway obstruction

Loss of a patent airway is a significant cause of prehospital death. Endotracheal intubation is the gold standard of care but has a high rate of failure and complications, making development of new devices vital. We previously showed that tracheal tissue has a unique spectral profile which could be utilized to confirm correct airway device placement. Therefore, the goals of this study were twofold: 1- to develop an airway obstruction model and 2- use that model to assess how airway compromise affects tissue reflectance. Female swine were anesthetized, intubated, and instrumented. Pigs were allowed to breathe spontaneously and underwent either slow- or rapid-onset obstruction until a real-time pulse oximeter reading of ≤50%. At baseline, 25%, 50%, 75%, and 100% obstruction, a fiber-optic reflection probe was inserted into the trachea and esophagus to capture reflectance spectra. Both slow- and rapid-onset obstruction significantly decreased arterial oxygen concentration (sO₂ ) and increased partial pressure of CO₂ (pCO₂ ). The presence of the tracheal-defining spectral profile was confirmed and remained consistent despite changes in sO₂ and pCO₂ . This study validated a model of slow- and rapid-airway obstruction that results in significant hypoxia and hypercapnia. This is valuable for future testing of airway device components that may improve airway management. Additionally, our data support the ability of spectral reflectance to differentiate between tracheal and esophageal tissues in the presence of a clinical condition that decreases oxygen saturation.

Safety of early tracheostomy in trauma patients after anterior cervical fusion

BACKGROUND

Cervical spine injuries (CSIs) can have major effects on the respiratory system and carry a high incidence of pulmonary complications. Respiratory failure can be due to spinal cord injuries, concomitant facial fractures or chest injury, airway obstruction, or cognitive impairments. Early tracheostomy (ET) is often indicated in patients with CSI. However, in patients with anterior cervical fusion (ACF), concerns about cross-contamination often delay tracheostomy placement. This study aimed to demonstrate the safety of ET within 4 days of ACF.

METHODS

Retrospective chart review was performed for all trauma patients admitted to our institution between 2001 and 2015 with diagnosis of CSI who required both ACF and tracheostomy, with or without posterior cervical fusion, during the same hospitalization. Thirty-nine study patients with ET (within 4 days of ACF) were compared with 59 control patients with late tracheostomy (5-21 days after ACF). Univariate and logistic regression analyses were performed to compare risk of wound infection, length of intensive care unit and hospital stay, and mortality between both groups during initial hospitalization.

RESULTS

There was no difference in age, sex, preexisting pulmonary or cardiac conditions, Glasgow Coma Scale score, Injury Severity Score, Chest Abbreviated Injury Scale score, American Spinal Injury Association score, cervical spinal cord injury levels, and tracheostomy technique between both groups. There was no statistically significant difference in surgical site infection between both groups. There were no cases of cervical fusion wound infection in the ET group (0%), but there were five cases (8.47%) in the late tracheostomy group (p = 0.15). Four involved the posterior cervical fusion wound, and one involved the ACF wound. There was no statistically significant difference in intensive care unit stay (p = 0.09), hospital stay (p = 0.09), or mortality (p = 0.06) between groups.

CONCLUSION

Early tracheostomy within 4 days of ACF is safe without increased risk of infection compared with late tracheostomy.

LEVEL OF EVIDENCE

Evidence, level III.

Use of Survey and Delphi Process to Understand Trauma Anesthesia Care Practices

BACKGROUND

Few trauma guidelines evaluate and recommend anesthesiology practices and there are no trauma anesthesia-specific guidelines. There is no information on how anesthesiologists perceive clinical practice patterns. Our objective was to understand the perceptions of anesthesiologists regarding trauma anesthesia practices.

METHODS

A survey assessing anesthesia management of trauma patients was distributed to 21,491 anesthesiologists. A subset of 10 of these questions was subsequently reviewed by a trauma anesthesiology focus group through a 3-round web-based Delphi process. A question was deemed to have respondent consensus if the response with the highest percentage of agreement was unchanged between rounds 1 and 2.

RESULTS

A total of 2360 anesthesiologists (11% response rate) responded to the survey. Results demonstrated that the practitioners' answers conflicted with existing surgical trauma society recommendations (ie, when to transfuse component therapy), and several areas that lacked any guidelines, resulted in response variability among anesthesiologists where not 1 answer achieved >75% agreement (ie, intubation technique of choice for patients with uncleared cervical spine). Thirteen trauma anesthesiologists participated in round 1 (response rate 100%), and 12 responded in rounds 2 and 3 (response rate 92%) of the Delphi process. None of the questions received 100% agreement. Consensus was achieved on 9 of 10 statements pertaining to trauma anesthesia care. Consensus was not reached on the intubating technique in a hemodynamically unstable patient with an uncleared cervical spine with deficits. Delphi participant opinion conflicted with existing guidelines on 2 statements: the use of cricoid pressure, and when to begin blood component therapy.

CONCLUSIONS

There are several important areas of trauma anesthesia practice where guidelines do not exist and several where existing guidelines are not endorsed by the majority of practitioners who completed our survey. The lack of consensus on trauma anesthesia management and the variation in survey responses demonstrate a need to develop evidence-based trauma anesthesia guidelines.

[The Berlin mass casualty hospital triage algorithm : Development, implementation and influence on exercise-based triage results]

BACKGROUND AND OBJECTIVE

Patient triage has a key function within the scope of the successful management of mass disasters and ensures the correct resource allocation. Analysis of unheralded hospital disaster training in Berlin hospitals revealed triage problems referring the correct classification of patients in the triage categories and relevant overtriaging and undertriaging. Therefore, a triage algorithm tailored to the clinical setting was developed in Berlin and after presentation and discussion within the circle of the representatives for clinical catastrophe protection, the algorithm was introduced as obligatory in 2015. This study was carried out to validate and investigate the effects of the triage algorithm.

MATERIAL AND METHODS

This prospective observational study evaluated all unheralded hospital disaster training exercises from 2016/2017 initiated by the senate administration, with 556 roughed persons after implementation of the new triage algorithm and compared the results with disaster training exercises from the years 2010/2011 without a triage algorithm (n = 601). The correct allocation of the prescribed injury patterns to the triage category (T1-3), specificity, sensitivity and positive likelihood ratio of the algorithm are described and group differences were calculated.

RESULTS

In 15 unheralded mass disaster drills with 556 actors in 2016-2017 a total of 85% of the category T1 (n = 83/98), 63% of the T2 category (n = 100/159) and 87% of the T3 category (n = 259/299) were correctly recognized. This corresponds to a significantly better triage result of 80% compared to 63% in 2010/2011. Overtriaging and undertriaging also were significantly reduced. The triage algorithm showed a specificity and sensitivity of 97% and 75%, respectively, for T1 (immediately life-threatening), 86%/67% for T2 (severely injured) and 85%/88% for T3 (slightly injured) patients.

DISCUSSION

The Berlin hospital triage algorithm was successfully validated. The triage category allocation was significantly improved in all relevant aspects after implementation with a significant reduction of overtriaging and undertriaging.

Advancing emergency airway management practice and research

Emergency airway management is one of the vital resuscitative procedures undertaken in the emergency department (ED). Despite its clinical and research importance in the care of critically ill and injured patients, earlier studies have documented suboptimal intubation performance and high adverse event rates with a wide variation across the EDs. The optimal emergency airway management strategies remain to be established and their dissemination to the entire nation is a challenging task. This article reviews the current published works on emergency airway management with a focus on the use of airway management algorithms as well as the importance of first‐pass success and systematic use of rescue intubation strategies. Additionally, the review summarizes the current evidence for each of the important airway management processes, such as assessment of the difficult airway, preparation (e.g., positioning and oxygenation), intubation methods (e.g., rapid sequence intubation), medications (e.g., premedications, sedatives, and neuromuscular blockades), devices (e.g., direct and video laryngoscopy and supraglottic devises), and rescue intubation strategies (e.g., airway adjuncts and rescue intubators), as well as the airway management in distinct patient populations (i.e., trauma, cardiac arrest, and pediatric patients). Well‐designed, rigorously conducted, multicenter studies that prospectively and comprehensively characterize emergency airway management should provide clinicians with important opportunities for improving the quality and safety of airway management practice. Such data will not only advance research into the determination of optimal airway management strategies but also facilitate the development of clinical guidelines, which will, in turn, improve the outcomes of critically ill and injured patients in the ED.

Trauma patients with prehospital Glasgow Coma Scale less than nine: not a homogenous group

PURPOSE

Prehospital guidelines stratify and manage patients with Glasgow Coma Scale (GCS) less than nine and any sign of head injury as affected by severe traumatic brain injury (STBI). We hypothesized that this group of patients is so inhomogeneous that uniform treatment guidelines cannot be advocated.

METHODS

Patients (2005-2012) with prehospital GCS below nine and abbreviated injury scale head and neck above two were identified from trauma registry. Patients with acute lethal injuries, isolated neck injuries, extubated within 24 h or transferred interhospitally were excluded. Patients were dichotomized based on the worst prehospital GCS (recorded before sedatives) into two groups: GCS 3-5 and GCS 6-8. These were statistically compared using univariate analysis.

RESULTS

The GCS 3-5 group (99 patients) when compared with the GCS 6-8 group (49 patients) had shorter prehospital times (63 vs. 79 min; p < 0.05), more frequent episodes of both hypoxia (30.3% vs. 7.7%; p < 0.05) and hypotension (26.7% vs. 6.4%; p < 0.05), more often required craniectomy (15.1% vs. 4.0%; p = 0.05) and higher mortality (33.3% vs. 2%; p < 0.05). In the GCS 3-5 group, prehospital endotracheal intubation was attempted more often (57.5% vs. 28.6%, p < 0.05) and was more often successful (39.3% vs. 10.2%; p = 0.05). Length of stay in ICU did not differ.

CONCLUSIONS

STBI patients are fundamentally different based on whether their initial GCS falls into 3-5 or 6-8 category. Recommendations from trials investigating trauma patients with GCS less than nine as one group should be translated with caution to clinical practice.

Necessity to depict difficult neck anatomy for training of cricothyroidotomy: A pilot study evaluating two surgical devices on a new hybrid training model

BACKGROUND

Everyone dealing with airway emergencies must be able to accomplish cricothyroidotomy, which cannot be trained in real patients. Training models are necessary.

OBJECTIVE

To evaluate the suitability of a hybrid training model combining synthetic and porcine parts to depict variable neck anatomy.

DESIGN

Model-based comparative trial.

SETTING

Armed Forces Hospital Ulm, Germany, August 2018.

INTERVENTION

On four anatomical neck variations (long slim/long obese/short slim/short obese) we performed two surgical approaches to cricothyroidotomy (SurgiCric II vs. ControlCric).

PARTICIPANTS

Forty-eight volunteers divided into two groups based on their personal skill level: beginners group and proficient performers group.

MAIN OUTCOME MEASURES

Time to completion was recorded for each procedure. Once the operator had indicated completion, the correct anatomical tube placement was confirmed by dissection and structures were inspected for complications. Primary outcomes were successful tracheal placement of an airway tube and time needed to achieve a patent airway. Secondary outcome was assessment of complications.

RESULTS

Overall, 384 procedures were performed. Median time to completion was 74 s. In total, 284 procedures (74%) resulted in successful ventilation. Time to completion was longer in short obese than in long slim and the risk of unsuccessful procedures was increased in short obese compared with long slim. Even if ControlCric resulted in faster completion of the procedure, its use was less successful and had an increased risk of complications compared with SurgiCric II. Proficient performers group performed faster but had an increased risk of injuring the tracheal wall compared with beginners group.

CONCLUSION

Participants had difficulties in performing cricothyroidotomy in obese models, but various and difficult anatomical situations must be expected in airway management and therefore must be taught. A new hybrid model combining porcine and synthetic materials offers the necessary conditions for the next step in training of surgical airway procedures.

TRIAL REGISTRATION

The study was performed without human tissue or living animals, and was therefore exempted from ethical review by the University of Ulm Ethical Committee, Germany (Chairperson Prof Dr C. Lenk) on 9 August 2018. Hence a protocol number was not attributed.

The European guideline on management of major bleeding and coagulopathy following trauma: fifth edition

BACKGROUND

Severe traumatic injury continues to present challenges to healthcare systems around the world, and post-traumatic bleeding remains a leading cause of potentially preventable death among injured patients. Now in its fifth edition, this document aims to provide guidance on the management of major bleeding and coagulopathy following traumatic injury and encourages adaptation of the guiding principles described here to individual institutional circumstances and resources.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004, and the current author group included representatives of six relevant European professional societies. The group applied a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were re-examined and revised based on scientific evidence that has emerged since the previous edition and observed shifts in clinical practice. New recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated.

RESULTS

Advances in our understanding of the pathophysiology of post-traumatic coagulopathy have supported improved management strategies, including evidence that early, individualised goal-directed treatment improves the outcome of severely injured patients. The overall organisation of the current guideline has been designed to reflect the clinical decision-making process along the patient pathway in an approximate temporal sequence. Recommendations are grouped behind the rationale for key decision points, which are patient- or problem-oriented rather than related to specific treatment modalities. While these recommendations provide guidance for the diagnosis and treatment of major bleeding and coagulopathy, emerging evidence supports the author group's belief that the greatest outcome improvement can be achieved through education and the establishment of and adherence to local clinical management algorithms.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. If incorporated into local practice, these clinical practice guidelines have the potential to ensure a uniform standard of care across Europe and beyond and better outcomes for the severely bleeding trauma patient.

Meta-Analysis of Post-Intubation Hypotension: A Plea to Consider Circulation First in Hypovolemic Patients

Hypovolemic patients can develop postintubation hypotension (PIH). Our objective is to review the literature regarding PIH and the association with mortality. We searched MEDLINE from inception to February 2018. A meta-analysis was performed to assess the effect of PIH on mortality. The results of the meta-analysis were reported in forest plots of the estimated effects of the included studies with a 95 per cent confidence interval. Heterogeneity was evaluated using the I2 test, which corresponded to low (I2 < 25%), medium (I2 = 25–75%), and high (I2 > 75%) heterogeneity. We identified 243 records. Four studies were included in the meta-analysis. The studies reported 2044 patients with 36.8 per cent (n = 753) developing PIH. Data indirectly reflecting the hemodynamic status were available in three studies (n = 1117 patients). Overall mortality was 24.6 per cent (n = 503) and was significantly higher in patients that developed PIH [mortality, n (%): PIH = 250/753 (33.2%) vs 253/1291 (19.6%), P < 0.001]. Patients that develop PIH have an increased mortality. Considering a targeted resuscitation in hypovolemic patients is pivotal to minimize PIH.

Rapid sequence induction (RSI) in trauma patients: Insights from healthcare providers

BACKGROUND

We aimed to describe the current practice of emergency physicians and anaesthesiologists in the selection of drugs for rapid-sequence induction (RSI) among trauma patients.

METHODS

A prospective survey audit was conducted based on a self-administered questionnaire among two intubating specialties. The preferred type and dose of hypnotics, opioids, and muscle relaxants used for RSI in trauma patients were sought in the questionnaire. Data were compared for the use of induction agent, opioid use and muscle relaxant among stable and unstable trauma patients by the intubating specialties.

RESULTS

A total of 102 participants were included; 47 were anaesthetists and 55 were emergency physicians. Propofol (74.5%) and Etomidate (50.0%) were the most frequently used induction agents. Significantly higher proportion of anesthesiologist used Propofol whereas, Etomidate was commonly used by emergency physicians in stable patients (P=0.001). Emergency physicians preferred Etomidate (63.6%) and Ketamine (20.0%) in unstable patients. The two groups were comparable for opioid use for stable patients. In unstable patients, use of opioid differed significantly by intubating specialties. The relation between rocuronium and suxamethonium use did change among the anaesthetists. Emergency physicians used more suxamethonium (55.6% vs. 27.7%, P=0.01) in stable as well as unstable (43.4 % vs. 27.7%, P=0.08) patients.

CONCLUSION

There is variability in the use of drugs for RSI in trauma patients amongst emergency physicians and anaesthesiologists. There is a need to develop an RSI protocol using standardized types and dose of these agents to deliver an effective airway management for trauma patients.

Trauma Airway Management: Induction Agents, Rapid Versus Slower Sequence Intubations, and Special Considerations

Trauma patients who require intubation are at higher risk for aspiration, agitation/combativeness, distorted anatomy, hemodynamic instability, an unstable cervical spine, and complicated injuries. Although rapid-sequence intubation is the most common technique in trauma, slow-sequence intubation may reduce the risk for failed intubation and cardiovascular collapse. Providers often choose plans with which they are most comfortable. However, developing a flexible team-based approach, through recognition of complicating factors in trauma patients, improves airway management success.

Coma After Acute Head Injury

BACKGROUND

Coma after acute head injury is always alarming. Depending on the type of injury, immediate treatment may be life-saving. About a quarter of a million patients are treated for traumatic brain injury in Germany each year. Treatment recommendations must be updated continually in the light of advancing knowledge.

METHODS

This review of treatment recommendations, prognostic factors, and the pathophysiology of coma after acute head injury is based on a 2015 German guideline for the treatment of head injury in adults and on pertinent publications retrieved by a selective search in PubMed for literature on post-traumatic coma.

RESULTS

As soon as the vital functions have been secured, patients with acute head injury should undergo cranial computed tomography, which is the method of choice for identifying intracranial injuries needing immediate treatment. Patients who have an intracranial hematoma with mass effect should be taken to surgery at once. The prognosis is significantly correlated with the patient's age, the duration of coma, accompanying neurological manifestations, and the site of brain injury. The case fatality rate of patients who have been comatose for 24 hours and who have accompanying lateralizing signs, a unilaterally absent pupillary light reflex, or hemiparesis lies between 30% and 50%. This figure rises to 50-60% in patients with abnormal extensor reflexes and to over 90% in those with bilaterally absent pupillary light reflexes. Current neuropathological and neuroradiological studies indicate that coma after acute head injury is due to reversible or irreversible dysfunction of the brainstem.

CONCLUSION

Brain tissue can tolerate ischemia and elevated pressure only for a very limited time. Comatose head-injured patients must therefore be evaluated urgently to determine whether they can be helped by the surgical removal of a hematoma or by a decompressive hemicraniectomy.

Airway management in pre-hospital critical care: a review of the evidence for a 'top five' research priority

The conduct and benefit of pre-hospital advanced airway management and pre-hospital emergency anaesthesia have been widely debated for many years. In 2011, prehospital advanced airway management was identified as a ‘top five’ in physician-provided pre-hospital critical care. This article summarises the evidence for and against this intervention since 2011 and attempts to address some of the more controversial areas of this topic.

Early FAST Examinations during Resuscitation May Compromise Trauma Outcomes

Focused assessment with Sonography for trauma (FAST) examination is essential to trauma triage. We sought to determine whether FASTs completed early in sequencing portend worse outcomes. A two-year review (2014–2015) of all trauma activations at our Level I trauma center was performed. Patients were matched at baseline and FAST times were compared. Outcomes included resuscitation time (RESUS-h), ventilation days (d), hospital length of stay (HLOS-d), ICU length of stay (LOS-d), survival (%), nosocomial infection rate (%), and venous thromboembolism complication rate (%). ED interventions included transfusions, crystalloid, antibiotics, central line placement, intubation, thoracostomy, thoracotomy, pelvic X-ray, and binder. One thousand, three hundred and twelve patients were included for analysis (mean age = 38 ± 19 years, mean Injury Severity Score = 12 ± 11, 21% penetrating). Compared with FASTs completed after the primary survey, early FASTs led to significantly more ventilation days ( P < 0.01), longer ICU length of stay ( P < 0.01), and a greater incidence of nosocomial infections ( P = 0.03). In the ED, early FASTs led to significantly more intubations ( P < 0.01) and transfusions ( P < 0.01) compared with late FASTs. FASTs completed before primary survey portend worse outcomes, with more ED interventions and equivocal results. FAST as a true adjunct to primary survey is recommended.

Hemodynamic Effects of Propofol for Induction of Rapid Sequence Intubation in Traumatically Injured Patients

Present guidelines for emergency intubation in traumatically injured patients recommend rapid sequence intubation (RSI) as the preferred method of airway management but specific pharmacologic agents for RSI remain controversial. To evaluate hemodynamic differences between propofol and other induction agents when used for RSI in trauma patients. Single-center, retrospective review of trauma patients intubated in the emergency department. Patients were divided in two groups based on induction agent, propofol or nonpropofol. The primary outcome was incidence of hypotension within 30 minutes of intubation. Secondary outcomes included hospital length of stay and inhospital mortality. The study protocol was approved by the Institutional Review Board. Of the 744 patients identified, 83 were analyzed, 43 in the propofol group and 40 in the nonpropofol group. Groups were similar at baseline in terms of pre-RSI hemodynamics, injury mechanism, initial Glasgow Coma Score, and Injury Severity Score. On univariate analysis, although not statistically significant, postintubation hypotension was more common in patients who received propofol compared with those who did not, 39.5 per cent versus 22.5 per cent (P = 0.9). When adjusted for age, Injury Severity Score, and pre-RSI hemodynamics, the risk of hypotension among propofol-treated patients was significantly higher (OR = 3.64; 95% Confidence interval 1.16–13.24). There were no significant differences between groups in hospital length of stay or mortality. Propofol increases the odds of postintubation hypotension in traumatically injured patients. Considerable caution should be used when contemplating the use of propofol the for induction of injured patients requiring RSI because other agents possess more favorable hemodynamic profiles.

Correlation between modified LEMON score and intubation difficulty in adult trauma patients undergoing emergency surgery

Background

Prediction of difficult airway is critical in the airway management of trauma patients. A LEMON method which consists of following assessments; Look-Evaluate-Mallampati-Obstruction-Neck mobility is a fast and easy technique to evaluate patients’ airways in the emergency situation. And a modified LEMON method, which excludes the Mallampati classification from the original LEMON score, also can be used clinically. We investigated the relationship between modified LEMON score and intubation difficulty score in adult trauma patients undergoing emergency surgery.

Methods

We retrospectively reviewed electronic medical records of 114 adult trauma patients who underwent emergency surgery under general anesthesia. All patients’ airways were evaluated according to the modified LEMON method before anesthesia induction and after tracheal intubation; the intubating doctor self-reported the intubation difficulty scale (IDS) score. A difficult intubation group was defined as patients who had IDS scores > 5.

Results

The modified LEMON score was significantly correlated with the IDS score (P < 0.001). The difficult intubation group showed higher modified LEMON score than the non-difficult intubation group (3 [2-5] vs. 2 [1-3], respectively, P = 0.017). Limited neck mobility was the only independent predictor of intubation difficulty (odds ratio, 6.15; P = 0.002).

Conclusion

The modified LEMON score is correlated with difficult intubation in adult trauma patients undergoing emergency surgery.

Expert-Performed Endotracheal Intubation-Related Complications in Trauma Patients: Incidence, Possible Risk Factors, and Outcomes in the Prehospital Setting and Emergency Department

The aim of this study was to determine complication rates and possible risk factors of expert-performed endotracheal intubation (ETI) in patients with trauma, in both the prehospital setting and the emergency department. We also investigated how the occurrence of ETI-related complications affected the survival of trauma patients. This single-center retrospective observational study included all injured patients who underwent anesthesiologist-performed ETI from 2007 to 2017. ETI-related complications were defined as hypoxemia, unrecognized esophageal intubation, regurgitation, cardiac arrest, ETI failure rescued by emergency surgical airway, dental trauma, cuff leak, and mainstem bronchus intubation. Of the 537 patients included, 23.5% experienced at least one complication. Multivariable logistic regression analysis revealed that low Glasgow Coma Scale Score (adjusted odds ratio [AOR], 0.93; 95% confidence interval [CI], 0.88-0.98), elevated heart rate (AOR, 1.01; 95% CI, 1.00-1.02), and three or more ETI attempts (AOR, 15.71; 95% CI, 3.37-73.2) were independent predictors of ETI-related complications. We also found that ETI-related complications decreased the likelihood of survival of trauma patients (AOR, 0.60; 95% CI, 0.38-0.95), independently of age, male sex, Injury Severity Score, Glasgow Coma Scale Score, and off-hours presentation. Our results suggest that airway management in trauma patients carries a very high risk; this finding has implications for the practice of airway management in injured patients.

A tale of two cities: prehospital intubation with or without paralysing agents for traumatic brain injury

BACKGROUND

The role of prehospital endotracheal intubation (PETI) for traumatic brain injury is unclear. In Victoria, paramedics use rapid sequence induction (RSI) drugs to facilitate PETI, while in New South Wales (NSW) they do not have access to paralysing agents. We hypothesized that RSI would both increase PETI rates and improve mortality.

METHODS

Retrospective comparison of adult primary admissions (Glasgow Coma Scale <9 and abbreviated injury scale head and neck >2) to either Victorian or NSW trauma centre, which were compared with univariate and logistic regression analysis to estimate odds ratio for mortality and intensive care unit (ICU) length of stay.

RESULTS

One hundred and ninety-two Victorian and 91 NSW patients did not differ in: demographics (males: 77% versus 79%; P = 0.7 and age: 34 (18-88) versus 33 (18-85); P = 0.7), Glasgow Coma Scale (3 (3-8) versus 5 (3-8); P = 0.07), and injury severity score (38 (26-75) versus 35 (18-75); P = 0.09), prehospital hypotension (15.4% versus 11.7%; P = 0.5) and desaturation (14.6% versus 17.5%; P = 0.5). Victorians had higher abbreviated injury scale head and neck (5 (4-5) versus 5 (3-6); P = 0.04) and more often successful PETI (85% versus 22%; P < 0.05). On logistic regression analysis, mortality did not differ among groups (31.7% versus 26.3%; P = 0.34; OR = 0.84; 95% CI: 0.38-1.86; P = 0.67). Among survivors, Victorians had longer stay in ICU (364 (231-486) versus 144 (60-336) h), a difference that persisted on gamma regression (effect = 1.58; 95% CI: 1.30-1.92; P < 0.05).

CONCLUSION

Paramedics using RSI to obtain PETI in patients with traumatic brain injury had a higher success rate. This increase in successful PETI rate was not associated with an improvement in either mortality rate or ICU length of stay.

Circulation first - the time has come to question the sequencing of care in the ABCs of trauma; an American Association for the Surgery of Trauma multicenter trial

Background

The traditional sequence of trauma care: Airway, Breathing, Circulation (ABC) has been practiced for many years. It became the standard of care despite the lack of scientific evidence. We hypothesized that patients in hypovolemic shock would have comparable outcomes with initiation of bleeding treatment (transfusion) prior to intubation (CAB), compared to those patients treated with the traditional ABC sequence.

Methods

This study was sponsored by the American Association for the Surgery of Trauma multicenter trials committee. We performed a retrospective analysis of all patients that presented to trauma centers with presumptive hypovolemic shock indicated by pre-hospital or emergency department hypotension and need for intubation from January 1, 2014 to July 1, 2016. Data collected included demographics, timing of intubation, vital signs before and after intubation, timing of the blood transfusion initiation related to intubation, and outcomes.

Results

From 440 patients that met inclusion criteria, 245 (55.7%) received intravenous blood product resuscitation first (CAB), and 195 (44.3%) were intubated before any resuscitation was started (ABC). There was no difference in ISS, mechanism, or comorbidities. Those intubated prior to receiving transfusion had a lower GCS than those with transfusion initiation prior to intubation (ABC: 4, CAB:9, p = 0.005). Although mortality was high in both groups, there was no statistically significant difference (CAB 47% and ABC 50%). In multivariate analysis, initial SBP and initial GCS were the only independent predictors of death.

Conclusion

The current study highlights that many trauma centers are already initiating circulation first prior to intubation when treating hypovolemic shock (CAB), even in patients with a low GCS. This practice was not associated with an increased mortality. Further prospective investigation is warranted.

Trial registration

IRB approval number: HM20006627. Retrospective trial not registered.

Intubation biomechanics: validation of a finite element model of cervical spine motion during endotracheal intubation in intact and injured conditions

OBJECTIVE

Because of limitations inherent to cadaver models of endotracheal intubation, the authors’ group developed a finite element (FE) model of the human cervical spine and spinal cord. Their aims were to 1) compare FE model predictions of intervertebral motion during intubation with intervertebral motion measured in patients with intact cervical spines and in cadavers with spine injuries at C-2 and C3–4 and 2) estimate spinal cord strains during intubation under these conditions.

METHODS

The FE model was designed to replicate the properties of an intact (stable) spine in patients, C-2 injury (Type II odontoid fracture), and a severe C3–4 distractive-flexion injury from prior cadaver studies. The authors recorded the laryngoscope force values from 2 different laryngoscopes (Macintosh, high intubation force; Airtraq, low intubation force) used during the patient and cadaver intubation studies. FE-modeled motion was compared with experimentally measured motion, and corresponding cord strain values were calculated.

RESULTS

FE model predictions of intact intervertebral motions were comparable to motions measured in patients and in cadavers at occiput–C2. In intact subaxial segments, the FE model more closely predicted patient intervertebral motions than did cadavers. With C-2 injury, FE-predicted motions did not differ from cadaver measurements. With C3–4 injury, however, the FE model predicted greater motions than were measured in cadavers. FE model cord strains during intubation were greater for the Macintosh laryngoscope than the Airtraq laryngoscope but were comparable among the 3 conditions (intact, C-2 injury, and C3–4 injury).

CONCLUSIONS

The FE model is comparable to patients and cadaver models in estimating occiput–C2 motion during intubation in both intact and injured conditions. The FE model may be superior to cadavers in predicting motions of subaxial segments in intact and injured conditions.

Peri-intubation factors affecting emergency physician choice of paralytic agent for rapid sequence intubation of trauma patients

INTRODUCTION

No study has assessed predictors of physician choice between the succinylcholine (Succ) and rocuronium (Roc) for rapid sequence intubation (RSI) during the initial resuscitation of trauma patients in the emergency department (ED).

METHODS

We retrospectively evaluated of the use of Succ and Roc for adult trauma patients undergoing RSI at a Level 1 trauma center. The primary outcome was to identify factors affecting physician choice of paralytic agent for RSI analyzed by cluster analysis using pre-intubation vital signs and early mortality. The secondary outcome was to identify factors influencing physician choice of paralytic agent using a logistic regression model reported as adjusted odds ratios (aOR).

RESULTS

The analysis included 215 patients, including 148 receiving Succ and 67 receiving Roc. The two groups were similar in regard to age, provider level of training, mean GCS (10 vs. 10) and median ISS (27 vs. 27). Cluster analysis using peri-intubation patient vital signs and early mortality indicates that patients with predominantly abnormal vital signs and early mortality were more likely to receive Roc (74%) than those without abnormal vital signs prior to intubation or early mortality (24%). Hypoxemia prior to RSI (aOR 12.3 [2.5-60.9]) and the use of video laryngoscopy (VL) (aOR 5.5 [1.2-24.6]) were associated with the choice to use Roc.

CONCLUSIONS

Roc was more frequently chosen for paralysis in the patient cluster with predominantly abnormal peri-intubation vital signs and higher rate of early ED mortality. The use of Roc was associated with hypoxemia prior to RSI and VL.

Thoracic trauma now and then: A 10 year experience from 16,773 severely injured patients

Background and purpose

Thoracic trauma remains to be a relevant injury to the polytraumatised patient. However, literature regarding how far changes in clinical guidelines for pre- and in-hospital trauma management and diagnostic procedures affect the outcome of multiple injured patients with severe chest injury during a long-term observation period is sparse.

Methods

Multiple traumatised patients (age≥16y) documented in the TraumaRegister DGU^® (TR-DGU) from January 1^st 2005 to December 31^st 2014 with severe chest trauma (AIS≥3) were included in this study. Demographic data, the pattern of injury, injury severity, radiographic emergency procedures, indication for intubation, duration of mechanical ventilation, emergency surgery, occurrence of complications and mortality were evaluated per year and over time.

Results

A total of 16,773 patients were analysed. The use of whole body computer tomography increased (p<0.001), while the incidence of plain x-rays decreased (p<0.001). Furthermore, incidence of AIS_Thorax = 3 graded injuries increased (p<0.001) while AIS_Thorax = 4 decreased (p<0.001). Both, rate of patients being intubated at the time of ICU admission decreased (p<0.001) and the time of mechanical ventilation decreased (p<0.001). Additionally, need for emergency surgery, lung failure, sepsis, and multi organ failure all decreased (p<0.001). However, mortality remained unchanged.

Interpretation

Severity of severe chest trauma and associated complications decreased while diagnostics and treatment improved over time. However, mortality remained unchanged. Our results are in line with those expected in the context of the incidence of CT diagnostics, which has increased parallel to the clinical outcome Thus, our data demonstrate a positive trend in the treatment of patients with severe chest trauma.

Assessment and Resuscitation in Trauma Management

The golden hour of trauma represents a crucial period in the management of acute injury. In an efficient trauma resuscitation, the primary survey is viewed as more than simple ABCs with multiple processes running in parallel. Resuscitation efforts should be goal oriented with defined endpoints for airway management, access, and hemodynamic parameters. In tandem with resuscitation, early identification of life-threatening injuries is critical for determining the disposition of patients when they leave the trauma bay. Salvage strategies for profoundly hypotensive or pulseless patients include retrograde balloon occlusion of the aorta and resuscitative thoracotomy, with differing populations benefiting from each.

Increased mortality in trauma patients who develop postintubation hypotension

BACKGROUND

Postintubation hypotension (PIH) is common and associated with poor outcomes in critically ill patient populations requiring emergency endotracheal intubation (ETI). The importance of PIH in the trauma population remains unclear. The objective of this study was to determine the prevalence of PIH in trauma patients and assess the association of PIH with patient outcomes.

METHODS

Retrospective case series of adult (≥16 years) patients who were intubated on arrival at a tertiary trauma center in Halifax, Nova Scotia, Canada, between 2000 and 2015. Data were collected from the Nova Scotia Trauma Registry and patient chart, and included demographics, comorbidities, trauma characteristics, intubation time, as well as all fluids, medications, adverse events, interventions, and vital signs during the 15 minutes before/after ETI. We evaluated the prevalence of PIH and created a logistic regression model to determine likelihood of mortality in the PIH and non-PIH groups after controlling for patient and provider characteristics.

RESULTS

Overall, 477 patients required ETI on assessment by the trauma service, of which 444 patients met eligibility criteria and were included in the analysis. The prevalence of PIH was 36.3% (161 of 444) in our study population. In-hospital mortality occurred in 29.8% (48 of 161) of patients in the PIH group, compared with 15.9% (45 of 283) of patients in the non-PIH group (p = 0.001). Development of PIH was associated with increased mortality in the emergency department (adjusted odds ratio, 3.45; 95% confidence interval, 1.42-8.36) and in-hospital (adjusted odds ratio, 1.83; 95% confidence interval, 1.01-3.31).

CONCLUSION

In our study of trauma patients requiring ETI, development of PIH was common (36.3%) and associated with increased mortality. Intubation practices in critically ill trauma patients is an important patient safety issue that requires further investigation.

LEVEL OF EVIDENCE

Prognostic and epidemiological, level III; Level IV, Therapeutic.

Cadaveric study of movement in the unstable upper cervical spine during emergency management: tracheal intubation and cervical spine immobilisation-a study protocol for a prospective randomised crossover trial

INTRODUCTION

Emergency management of upper cervical spine injuries often requires cervical spine immobilisation and some critical patients also require airway management. The movement of cervical spine created by tracheal intubation and cervical spine immobilisation can potentially exacerbate cervical spinal cord injury. However, the evidence that previous studies have provided remains unclear, due to lack of a direct measurement technique for dural sac's space during dynamic processes. Our study will use myelography method and a wireless human motion tracker to characterise and compare the change of dural sac's space during tracheal intubations and cervical spine immobilisation in the presence of unstable upper cervical spine injury such as atlanto-occipital dislocation or type II odontoid fracture.

METHODS AND ANALYSIS

Perform laryngoscopy and intubation, video laryngoscope intubation, laryngeal tube insertion, fiberoptic intubation and cervical collar application on cadaveric models of unstable upper cervical spine injury such as atlanto-occipital dislocation or type II odontoid fracture. The change of dural sac's space and the motion of unstable cervical segment are recorded by video fluoroscopy with previously performing myelography, which enables us to directly measure dural sac's space. Simultaneously, the whole cervical spine motion is recorded at a wireless human motion tracker. The maximum dural sac compression and the maximum angulation and distraction of the injured segment are measured by reviewing fluoroscopic and myelography images.

ETHICS AND DISSEMINATION

This study protocol has been approved by the Ethics Committee of the State Medical Association Rhineland-Palatinate, Mainz, Germany. The results will be published in relevant emergency journals and presented at relevant conferences.

TRIAL REGISTRATION NUMBER

DRKS00010499.

A systematic review and meta-analysis comparing mortality in pre-hospital tracheal intubation to emergency department intubation in trauma patients

Background

Pre-hospital endotracheal intubation is frequently used for trauma patients in many emergency medical systems. Despite a wide range of publications in the field, it is debated whether the intervention is associated with a favourable outcome, when compared to more conservative airway measures.

Methods

A systematic literature search was conducted to identify interventional and observational studies where the mortality rates of adult trauma patients undergoing pre-hospital endotracheal intubation were compared to those undergoing emergency department intubation.

Results

Twenty-one studies examining 35,838 patients were included. The median mortality rate in patients undergoing pre-hospital intubation was 48% (range 8–94%), compared to 29% (range 6–67%) in patients undergoing intubation in the emergency department. Odds ratios were in favour of emergency department intubation both in crude and adjusted mortality, with 2.56 (95% CI: 2.06, 3.18) and 2.59 (95% CI: 1.97, 3.39), respectively. The overall quality of evidence is very low. Twelve of the twenty-one studies found a significantly higher mortality rate after pre-hospital intubation, seven found no significant differences, one found a positive effect, and for one study an analysis of the mortality rate was beyond the scope of the article.

Conclusions

The rationale for wide and unspecific indications for pre-hospital intubation seems to lack support in the literature, despite several publications involving a relatively large number of patients. Pre-hospital intubation is a complex intervention where guidelines and research findings should be approached cautiously. The association between pre-hospital intubation and a higher mortality rate does not necessarily contradict the importance of the intervention, but it does call for a thorough investigation by clinicians and researchers into possible causes for this finding.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1787-x) contains supplementary material, which is available to authorized users.

Comparison of Etomidate and Ketamine for Induction During Rapid Sequence Intubation of Adult Trauma Patients

STUDY OBJECTIVE

Induction doses of etomidate during rapid sequence intubation cause transient adrenal dysfunction, but its clinical significance on trauma patients is uncertain. Ketamine has emerged as an alternative for rapid sequence intubation induction. Among adult trauma patients intubated in the emergency department, we compare clinical outcomes among those induced with etomidate and ketamine.

METHODS

The study entailed a retrospective evaluation of a 4-year (January 2011 to December 2014) period spanning an institutional protocol switch from etomidate to ketamine as the standard induction agent for adult trauma patients undergoing rapid sequence intubation in the emergency department of an academic Level I trauma center. The primary outcome was hospital mortality evaluated with multivariable logistic regression, adjusted for age, vital signs, and injury severity and mechanism. Secondary outcomes included ICU-free days and ventilator-free days evaluated with multivariable ordered logistic regression using the same covariates.

RESULTS

The analysis included 968 patients, including 526 with etomidate and 442 with ketamine. Hospital mortality was 20.4% among patients induced with ketamine compared with 17.3% among those induced with etomidate (adjusted odds ratio [OR] 1.41; 95% confidence interval [CI] 0.92 to 2.16). Patients induced with ketamine had ICU-free days (adjusted OR 0.80; 95% CI 0.63 to 1.00) and ventilator-free days (adjusted OR 0.96; 95% CI 0.76 to 1.20) similar to those of patients induced with etomidate.

CONCLUSION

In this analysis spanning an institutional protocol switch from etomidate to ketamine as the standard rapid sequence intubation induction agent for adult trauma patients, patient-centered outcomes were similar for patients who received etomidate and ketamine.

3D force/torque characterization of emergency cricothyroidotomy procedure using an instrumented scalpel

Emergency Cricothyroidotomy (CCT) is a surgical procedure performed to secure a patient's airway. This high-stakes, but seldom-performed procedure is an ideal candidate for a virtual reality simulator to enhance physician training. For the first time, this study characterizes the force/torque characteristics of the cricothyroidotomy procedure, to guide development of a virtual reality CCT simulator for use in medical training. We analyze the upper force and torque thresholds experienced at the human-scalpel interface. We then group individual surgical cuts based on style of cut and cut medium and perform a regression analysis to create two models that allow us to predict the style of cut performed and the cut medium.

Exam 4 Questions

A 73-year-old male with a history of hypertension and hyperlipidemia is currently in the stroke unit after suffering a right middle cerebral artery infarct. His symptoms started 2 h prior to arrival at the hospital, and tPA was administered. The patient is plegic on the left side and with mild dysarthria, but is otherwise neurologically intact. His labwork is within normal limits. Which of the following describes the optimal deep venous thrombosis (DVT) prophylaxis regimen for this patient?A.

Wait 6 h post tPA, then administer unfractionated heparin (UFH) along with intermittent pneumatic compression (IPC)

B.

Wait 24 h post tPA, then administer UFH along with IPC

C.

Wait 6 h post tPA, then administer low molecular weight heparin (LMWH) along with IPC

D.

Wait 24 h post tPA, then administer LMWH along with IPC

E.

IPC only for the first 72 h, then LMWH or UFH after obtaining follow-up imaging

All of the following causes of acute encephalitis have the matching characteristic radiological features except:A.

Autoimmune limbic encephalitis: T2/FLAIR hyperintensity in the mesial temporal lobes

B.

Cytomegalovirus: T2/FLAIR hyperintensity in the subependymal white matter

C.

JC virus: T2/FLAIR hyperintensity in the parieto-occipital lobes and corpus callosum

D.

Herpes simplex virus type 1: restricted diffusion in frontal/temporal lobes and insular cortex

E.

Varicella zoster: T2/FLAIR hyperintensity in the brainstem

Which of the following categorizations is most accurate regarding acute respiratory distress syndrome (ARDS) in the setting of subarachnoid hemorrhage (SAH)?A.

Non-neurogenic, non-cardiogenic

B.

Neurogenic, non-cardiogenic

C.

Neurogenic, cardiogenic

D.

Non-neurogenic, cardiogenic

E.

None of the above accurately reflect ARDS in SAH

A 52-year-old female is admitted to the ICU with a Hunt-Hess 1, modified Fisher 2 subarachnoid hemorrhage. Her past medical history is significant for hypertension, diabetes mellitus, and chronic renal insufficiency. She undergoes craniotomy for surgical clipping of an anterior cerebral artery aneurysm, and does not experience any additional complications. Two weeks later, she begins complaining of left calf pain, and a lower extremity sonogram demonstrated a proximal deep venous thrombosis (DVT). The patient weighs 60 kg. Her laboratory values are as follows: sodium 142 mEq/L, potassium 3.4 mEq/L, carbon dioxide 18 mEq/L, blood urea nitrogen (BUN) 70 mg/dL, and serum creatinine 2.5 mg/dL. What would be the optimal treatment for this patient’s proximal DVT?A.

Unfractionated heparin infusion for at least 5 days concomitantly with warfarin therapy

B.

Low molecular weight heparin 60 mg twice a day for at least 5 days concomitantly with warfarin therapy

C.

Fondaparinux 7.5 mg daily for 5 days followed by warfarin therapy

D.

Apixaban 10 mg twice daily for 7 days followed by 5 mg twice daily

E.

Rivaroxaban 15 mg twice daily for 21 days followed by 20 mg once daily

All of the following are currently implicated in uremic encephalopathy except:A.

Derangements in cerebral metabolism

B.

Alterations in the blood-brain barrier

C.

Accumulation of circulating toxins

D.

Imbalance of endogenous neurotransmitters

E.

Recurrent lobar hemorrhages

A 70-year-old female is hospitalized with a recent ischemic infarct. As part of stroke core measures, you obtain a hemoglobin A1c of 10.0. What is an approximate estimation of this patient’s average blood glucose level over the last several months?A.

70 mg/dL

B.

100 mg/dL

C.

130 mg/dL

D.

190 mg/dL

E.

240 mg/dL

A 28-year-old female with no known past medical history is in the ICU in status epilepticus, with anti-N-methyl D-aspartate (NMDA) receptor antibodies isolated in the cerebrospinal fluid. Which of the following is most likely to identify the root cause of her illness?A.

Transvaginal ultrasound

B.

Contrast-enhanced CT of the chest

C.

Contrast-enhanced CT of the brain

D.

Virtual colonography

E.

Thorough examination of the skin, particularly in sun-exposed areas

A 17-year-old male with no significant past medical history collapses during a high school football game, and goes into cardiac arrest. He did not have any complaints earlier in the day. The patient is brought to a nearby hospital, where is he resuscitated, intubated, and transferred to the ICU for further management. The patient is currently undergoing therapeutic hypothermia, and a work-up is underway to determine the cause of his sudden collapse. Which of the following is the most likely diagnosis?A.

Rupture of a previously undiagnosed cerebral aneurysm

B.

Hypertrophic cardiomyopathy

C.

Commotio cordis

D.

Severe hyponatremia and cerebral edema

E.

Brugada syndrome

A 31-year-old female at 38 weeks gestation is currently hospitalized for the treatment of preeclampsia. Due to her medical condition, her obstetrician is currently considering induced labor. At which point will this patient no longer be at risk for developing frank seizure activity as a result of her condition?A.

48 h postpartum

B.

1 week after delivery

C.

2 weeks after delivery

D.

4 weeks after delivery

E.

6 weeks after delivery

A 38-year-old male with no prior medical history presents to the emergency department with fever and severe headaches for several days. A CT scan of the brain is unremarkable, and the results of a lumbar puncture are pending. What is the most appropriate empiric antimicrobial regimen at this time?A.

Cefazolin and vancomycin

B.

Ceftriaxone and vancomycin

C.

Ceftriaxone, vancomycin and ampicillin

D.

Piperacillin/tazobactam and vancomycin

E.

Meropenem and vancomycin

The majority of intramedullary spinal cord neoplasms are:A.

Astrocytomas

B.

Meningiomas

C.

Metastatic lesions

D.

Ependymomas

E.

Hemangioblastomas

Which of the following derived parameter formulas is correct?A.

Cardiac index = cardiac output x body surface area

B.

Stroke volume = cardiac output/heart rate

C.

Systemic vascular resistance = 80 × (mean arterial pressure/cardiac output)

D.

Pulmonary vascular resistance = 80 × (mean pulmonary artery pressure/cardiac output)

E.

All of the above are correct

A 23-year-old female marathon runner is currently in the ICU after suffering from heat stroke following an outdoor run on a particularly hot summer day. She was initially delirious in the emergency department, but progressed to coma and respiratory failure requiring mechanical ventilation. Her oral temperature is 42.1 °C. Which of the following would be most effective in reducing this patient’s severe hyperthermia?A.

Regularly scheduled alternating acetaminophen and ibuprofen

B.

Spraying room temperature water on the patient, followed by fanning

C.

Ice water immersion

D.

Dantrolene sodium, 2.5 mg/kg

E.

Application of ice packs to the groin and axilla

Hyperinsulinemia-euglycemia (HIE) therapy may be useful for toxicity related to which of the following?A.

Tricyclic antidepressants

B.

Calcium channel blockers

C.

Aspirin

D.

Digoxin

E.

Lithium

A 71-year-old female with a history of alcohol abuse is currently intubated in the ICU following a catastrophic spontaneous left basal ganglia hemorrhage with resultant herniation. You have just declared her brain dead. The patient’s family agrees to make her an organ donor, and the organ donation coordinator requests you initiate levothyroxine therapy. Which of the following benefits would be expected with this treatment?A.

Increase the number of solid organs available for transplant

B.

Eliminate the need for hepatic biopsy prior to liver transplant

C.

Eliminate the need for cardiac catheterization prior to heart transplant

D.

Eliminate the need for bronchoscopy prior to lung transplant

E.

Reduce the need for supplementation of sodium, potassium, calcium, and magnesium

Which of the following is not an element of the Full Outline of Unresponsiveness (FOUR) score?A.

Eye opening

B.

Respiratory function

C.

Brainstem reflexes

D.

Motor response

E.

Verbal response

A 23-year-old female is currently in the ICU with status asthmaticus. She was initially on noninvasive positive pressure ventilation, with an arterial blood gas (ABG) as follows: pH 7.13, pCO₂ 60 mmHg, PaO₂ is 61 mmHg, HCO₃ 24 mmol/L, and oxygen saturation of 90%. She is given continuous inhaled albuterol, intravenous steroids, and magnesium sulfate. She subsequently becomes more lethargic and is intubated, with settings as follows: volume assist-control, rate of 12 breaths/min, tidal volume of 500 cc, PEEP of 5 cm H₂O, and FiO₂ of 50%. Peak airway pressure is 50 cm H₂O and plateau pressure is 15 cm H₂O. A stat portable chest x-ray shows hyperinflation with no pneumothorax. A repeat ABG after 30 min of invasive ventilation shows the following: pH of 7.24, pCO₂ 49 mmHg, PaO₂ 71 mmHg, HCO₃ is 25 mmol/L. Which of the following should be performed next?A.

Increase rate to 16

B.

Increase tidal volume to 600 cc

C.

Initiate bicarbonate infusion

D.

Switch to pressure assist-control

E.

Maintain current settings

Which of the following mechanisms is implicated in super-refractory status epilepticus?A.

Influx of proinflammatory molecules

B.

Upregulation of NMDA receptors

C.

Upregulation of molecular transport molecules

D.

Downregulation of GABA receptors

E.

All of the above

A 85-year-old male with a history nephrolithiasis, mild dementia, and alcohol abuse presented to the emergency department after a fall from standing, and was found to a right holohemispheric subdural hematoma. His clot was evacuated successfully, in spite of his oozing diathesis in the operating room (INR on arrival was 1.4 with a platelet count of 88 × 10³/μL). His serum transaminases are twice the normal value, and he has had refractory chronic hyponatremia. He has had three convulsions during this week of hospitalization, in spite of levetiracetam therapy at 1.5 g twice a day. Over the past 24 h, he has had a marked increase in agitation. He has also just had a 5-s run of non-sustained ventricular tachycardia, and his systolic blood pressure is now 85 mmHg. You are considering discontinuing his levetiracetam and starting a new agent. Which of the following would be the best choice in this scenario?A.

Carbamazepine

B.

Phenytoin

C.

Valproate

D.

Lacosamide

E.

Topiramate

A 65-year-old male with a history of COPD on rescue albuterol and ipratropium is diagnosed with myasthenia gravis, and started on an acetylcholinesterase inhibitor. He returns several days later complaining of increased salivation and worsening bronchial secretions in the absence of fevers, purulent sputum, or increasing dyspnea. These symptoms are not relieved by use of his albuterol. On exam, he has slightly decreased air movement throughout both lung fields without any clear wheezing, no focal rales, and a normal inspiratory to expiratory ratio. Which treatment option is most likely to be beneficial?A.

Increase frequency of short-acting ß₂ agonist use

B.

Add a standing long-acting inhaled ß₂ agonist

C.

Add glycopyrrolate as needed

D.

Add inhaled corticosteroids

E.

Add oral systemic corticosteroids

Regarding states of impaired consciousness, which of the following statements regarding arousal and awareness is correct?A.

Coma: intact arousal, but impaired awareness

B.

Minimally conscious state: impaired arousal and impaired awareness

C.

Persistent vegetative state: intact arousal, but impaired awareness

D.

Locked-in state: intact arousal, but impaired awareness

E.

All of the above are correct

A 62-year-old female is currently in the ICU following craniotomy for clipping of a cerebral aneurysm. Postoperatively, she is noted to have an oxygen saturation of 92% on 50% non-rebreather face mask, and her respiratory rate is 32 breaths/min. She denies chest pain. Her blood pressure is 96/72 mmHg and heart rate is 120 beats/min. Nimodipine has been held according to blood pressure parameters. A portable chest x-ray shows hazy opacities bilaterally, and bedside echocardiogram shows decreased left ventricular systolic function with apical, septal, lateral, anterior, anteroseptal and inferolateral wall akinesis, along with apical ballooning. Which of the following should be performed next?A.

Intubate the patient and begin mechanical ventilation

B.

Call urgent cardiology consult for cardiac catheterization

C.

Start noninvasive positive airway pressure ventilation

D.

Administer broad spectrum antibiotics

E.

Administer albuterol and systemic corticosteroids

Which of the following is the most common etiology of acute spinal cord ischemia and infarction?A.

Atherosclerotic disease

B.

Rupture of an abdominal aortic aneurysm

C.

Degenerative spine disease

D.

Cardioembolic events

E.

Systemic hypotension in the setting of other disease processes

A 62-year-old female with a history of coronary artery disease has just been admitted to the ICU with a left-sided spontaneous basal ganglia hemorrhage. The patient takes 325 mg of aspirin daily at home, and you are considering platelet transfusion. Which of the following has been demonstrated regarding platelet transfusion in this setting?A.

Improved chances of survival to hospital discharge

B.

Decreased hospital length-of-stay

C.

Improved chances of survival at 3 months

D.

Improved modified Rankin scale at 3 months

E.

None of the above

Which of the following therapies has been shown to decrease the incidence of delayed cerebral ischemia (DCI) in the setting of subarachnoid hemorrhage (SAH)?A.

Atorvastatin

B.

Magnesium

C.

Methylprednisolone

D.

Nicardipine

E.

None of the above

A 70-year-old male with a history of diabetes, hypertension, and cigarette smoking (one pack per day for the last 40 years) is currently in the ICU with a COPD exacerbation. This is his third exacerbation this year, and was discharged from the hospital only 3 weeks prior. On your examination, he is alert, his breathing is labored, and he has rales at the right lung base. His vital signs are as follows: blood pressure 90/60 mmHg, heart rate 120 beats per minute, respirations 28 per minute, and temperature 38.3 °C. His oxygen saturation on 50% face mask is 93%, and his most recent PCO₂ is 55 mmHg. Labs are notable for the following: white blood cell count 14.4 × 10⁹/L with 90% neutrophils, blood urea nitrogen (BUN) 30 mg/dL, serum creatinine 1.2 mg/dL, and glucose 240 mg/dL. Ketones are negative. He is currently on noninvasive positive pressure ventilation at 10/5 cm H₂O and 50% FiO₂, and broad spectrum antibiotics have been administered. An hour later, the nurse pages you because his heart rate is now 140 beats per minute and irregular, blood pressure is 85 systolic, oxygen saturation is 85%, and he is minimally responsive. You now hear bilateral rales, most prominently in the right lung base, and scattered wheezes. Which of the following should be performed next?A.

Increase inspiratory pressure to 15 and FiO₂ to 100%

B.

Start a continuous diltiazem infusion and give intravenous furosemide

C.

Start a continuous phenylephrine infusion targeting a mean arterial pressure (MAP) > 65

D.

Give 125 mg of solumedrol and administer albuterol via nebulizer

E.

Intubate the patient and initiate mechanical ventilation

A 57-year-old male with a history of epilepsy is currently in the stroke unit following a large right middle cerebral artery infarction. A nasogastric tube has been inserted, and 24 h continuous enteral feeds have been initiated. The patient is currently on 100 mg of phenytoin every 8 h for seizure prophylaxis. Which of the following measures should be taken to prevent the patient from developing subtherapeutic phenytoin levels?A.

Change to 18 h tube feeds, and only administer phenytoin at night

B.

Change to 18 h tube feeds, and only administer phenytoin twice daily

C.

Switch from standard to hydrolyzed tube feeds

D.

Switch from standard to glycemic control tube feeds

E.

Hold tube feeds for 2 h before and after phenytoin administration

A 37-year-old female presents to the emergency department with approximately 2 weeks of progressively worsening clumsiness and drastic mood swings. Her past medical history is significant only for Crohn’s disease, for which she takes both natalizumab and infliximab. A contrast-enhanced CT scan of her head is performed, revealing hypodense, non-enhancing lesions in the cortical white matter of the frontal and parietal lobes. Despite treatment, the patient expires 1 month later. Which of the following is true regarding the most likely diagnosis?A.

The diagnosis may be confirmed via CSF analysis

B.

The pathologic process spares oligodendrocytes

C.

It is a prion-based disease

D.

The condition is universally fatal despite treatment

E.

All of the above

A 58-year-old female presents to the emergency department with dry cough, fever and rapidly progressive dyspnea over 1 week. She has a history of rheumatoid arthritis (RA) and is maintained on weekly methotrexate and daily prednisone (which was increased to 30 mg starting 1 month ago for an acute flare). She takes no other medications. Her vital signs are as follows: blood pressure 100/70 mmHg, heart rate 110 beats/min, respiratory rate 20 breaths/min, and temperature 38.0 °C. In the ED she develops progressive hypoxemia with oxygen saturation 92% on 100% nonrebreather, and is increasingly diaphoretic. She is emergently intubated, and a chest x-ray post intubation shows extensive bilateral lung opacities. Which of the following should be administered at this time?A.

Ceftriaxone and azithromycin

B.

Vancomycin and piperacillin-tazobactam

C.

Vancomycin, cefepime, and fluconzole

D.

Ceftriaxone, levofloxacin, and trimethoprim-sulfamethoxazole

E.

Tigecycline only

A 45-year-old woman undergoes uncomplicated transsphenoidal resection of a pituitary macroadenoma. She appears well hydrated and is not complaining of excessive thirst. Post-operatively, she is noted to have increased urine output. Serum sodium is 137 mEq/L, and serum osmolarity is 275 mOsm/kg. What is the most likely cause of her polyuria?A.

Syndrome of inappropriate antidiuretic hormone

B.

Diabetes insipidus

C.

Cerebral salt wasting

D.

Fluid mobilization

E.

All of the above are equally likely

A 36-year-old female with a recent lumbar puncture to rule out subarachnoid hemorrhage is now complaining of a severe headache unlike anything she has experienced previously. She reports her headache is worse when standing, and better upon lying flat. She is otherwise neurologically intact. All of the following medications may be beneficial in this scenario except:A.

Acetaminophen

B.

Ibuprofen

C.

Caffeine

D.

Aminophylline

E.

Methylprednisolone

Which of the following is the most common overall cause of acute myocardial infarction?A.

Coronary dissection

B.

Plaque rupture

C.

Imbalance between oxygen demand and supply across a fixed obstruction

D.

Coronary vasospasm

E.

Ischemia related to hypotension and decreased perfusion

A 78-year-old male is in the ICU recovering from sepsis and pneumonia. He was just recently extubated after 2 days of mechanical ventilation and sedation with a fentanyl infusion. Over the ensuing days, he develops worsening abdominal distention, poor bowel sounds, and no stool output. CT scan reveals significant colonic distention, but no mass or obstruction. Records demonstrate a normal routine colonoscopy performed 6 weeks ago. You have appropriately hydrated the patient, corrected any electrolyte abnormalities, placed a rectal tube, withheld all opiates, and given intravenous erythromycin, but to no avail. Abdominal x-rays continue to demonstrate marked cecal dilatation greater than 12 cm in diameter. What is the next best appropriate therapy for this patient?A.

Neostigmine

B.

Naloxone

C.

Metoclopromide

D.

Surgical consultation for hemicolectomy

E.

Endoscopic percutaneous cecostomy tube placement

Which of the following is the most common cerebral vascular malformation in the general population?A.

AV malformation

B.

Dural AV fistula

C.

Developmental venous anomaly

D.

Cavernous malformation

E.

Vein of Galen malformation

A 49-year-old female with a history of acute lymphoblastic leukemia and recent subcutaneous cerebrospinal fluid (CSF) reservoir placement presents to the emergency department with fever, chills, and increased confusion for the past 3 days. Her CSF reservoir was last accessed 1 week ago. A thorough work-up reveals no other obvious infectious source, and there is concern for CSF reservoir-associated meningitis. Which of the following is the most likely causative organism?A.

Coagulase-negative staphylococci

B.

Propionobacterium acnes

C.

Methicillin-resistant Staphylococcus aureus

D.

Klebsiella pneumoniae

E.

Neisseria meningitidis

A 47-year-old woman presents to the emergency department with headache, nausea, and vomiting. Non-contrast head CT is performed, revealing subarachnoid blood in the right Sylvian fissure, and conventional angiography reveals the presents of a large right-sided MCA aneurysm. The patient undergoes successful surgical clipping of her aneurysm, and is being observed in the ICU. On admission, the patient’s serum sodium was 142 mEq/L and the hematocrit was 37%; by the seventh post-operative day, the serum sodium is 127 mEq/L and the hematocrit is 44%. Bedside ultrasonography demonstrates an IVC diameter of approximately 0.9 cm. Which of the following interventions would be least reasonable at this time?A.

Fludrocortisone, 0.2 mg twice a day

B.

2% hypertonic saline, infused peripherally

C.

3% hypertonic saline, infused centrally

D.

Sodium chloride oral tablets

E.

1500 mL daily fluid restriction

Which of the following is true regarding central (non-infectious) fever?A.

Less common in subarachnoid hemorrhage

B.

More common versus infectious fever

C.

Earlier onset versus infectious fever

D.

Easier to confirm versus infectious fever

E.

All of the above

Flaccid paralysis is most commonly associated with which of the following forms of encephalitis?A.

West Nile

B.

Varicella zoster

C.

Rabies

D.

Herpes simplex

E.

Epstein-Barr

Which of the following would not be considered appropriate therapy for heparin-induced thrombocytopenia (HIT)?A.

Discontinuation of heparin products alone

B.

Danaparoid

C.

Fondaparinux

D.

Argatroban

E.

All of the above are acceptable treatment options

A 45-year-old male with severe blunt traumatic brain injury (TBI) from a motor vehicle collision suffered a ventricular fibrillation cardiac arrest at the time of injury with return of spontaneous circulation (ROSC) in the field after endotracheal intubation and one dose of epinephrine. On arrival to the emergency department, no regional wall motion abnormalities were noted on surface echocardiography and no ST segment changes were seen on the presenting EKG. Head CT revealed cerebral contusions but no extra-axial mass lesions. The patient is now in the ICU and found to be comatose without sedation. Mild therapeutic hypothermia to 33° is being considered in the management of this post-arrest patient. Which of the following statements is true?A.

Mild therapeutic hypothermia is contraindicated due to the risk of induced epilepsy

B.

Mild therapeutic hypothermia is contraindicated with any intracranial pathology on CT imaging

C.

Mild therapeutic hypothermia does not induce a clinically significant coagulopathy

D.

Patients who have sustained ROSC after an arrest associated with TBI do not benefit from therapeutic hypothermia

E.

Endovascular cooling is superior to surface cooling in young patients with ROSC

A 35-year-old male is in the intensive care unit following resection of a large right-sided meningioma. He is currently intubated and sedated on a continuous fentanyl infusion. The nurse calls you to the bedside due to concerns over “unusual ventilator waveforms”. Upon arrival, you note the following (see Image 1). What is the best way to describe this phenomenon?A.

Reverse triggering

B.

Double triggering

C.

Breath stacking

D.

Missed triggering

E.

None of the above; normal ventilator waveforms are present

Emergency Surgical Airways Following Activation of a Difficult Airway Management Team in Hospitalized Critically Ill Patients: A Case Series

INTRODUCTION

An emergency surgical airway (ESA) is widely recommended for securing the airway in critically ill patients who cannot be intubated or ventilated. Little is known of the frequency, clinical circumstances, management methods, and outcomes of hospitalized critically ill patients in whom ESA is performed outside the emergency department or operating room environments.

METHODS

We retrospectively reviewed all adult patients undergoing ESA in our intensive care units (ICUs) and other hospital units from 2008 to 2012 following activation of our difficult airway management team (DAMT).

RESULTS

Of 207 DAMT activations for native airway events, 22 (10.6%) events culminated in an ESA, with 59% of these events occurring in ICUs with the remainder outside the ICU in the context of rapid response team activations. Of patients undergoing ESA, 77% were male, 63% were obese, and 41% had a history of a difficult airway (DA). Failed planned or unplanned extubations preceded 61% of all ESA events in the ICUs, while bleeding from the upper or lower respiratory tract led to ESA in 44% of events occurring outside the ICU. Emergency surgical airway was the primary method of airway control in 3 (14%) patients, with the remainder of ESAs performed following failed attempts to intubate. Complications occurred in 68% of all ESAs and included bleeding (50%), multiple cannulation attempts (36%), and cardiopulmonary arrest (27%). Overall hospital mortality for patients undergoing ESA was 59%, with 38% of deaths occurring at the time of the airway event.

CONCLUSION

An ESA is required in approximately 10% of DA events in critically ill patients and is associated with high morbidity and mortality. Efforts directed at early identification of patients with a difficult or challenging airway combined with a multidisciplinary team approach to management may reduce the overall frequency of ESA and associated complications.

Intubation biomechanics: laryngoscope force and cervical spine motion during intubation in cadavers—effect of severe distractive-flexion injury on C3–4 motion

OBJECTIVE

With application of the forces of intubation, injured (unstable) cervical segments may move more than they normally do, which can result in spinal cord injury. The authors tested whether, during endotracheal intubation, intervertebral motion of an injured C3–4 cervical segment 1) is greater than that in the intact (stable) state and 2) differs when a high- or low-force laryngoscope is used.

METHODS

Fourteen cadavers underwent 3 intubations using force-sensing laryngoscopes while simultaneous cervical spine motion was recorded with lateral fluoroscopy. The first intubation was performed with an intact cervical spine and a conventional high-force line-of-sight Macintosh laryngoscope. After creation of a severe C3–4 distractive-flexion injury, 2 additional intubations were performed, one with the Macintosh laryngoscope and the other with a low-force indirect video laryngoscope (Airtraq), used in random order.

RESULTS

During Macintosh intubations, between the intact and the injured conditions, C3–4 extension (0.3° ± 3.0° vs 0.4° ± 2.7°, respectively; p = 0.9515) and anterior-posterior subluxation (−0.1 ± 0.4 mm vs −0.3 ± 0.6 mm, respectively; p = 0.2754) did not differ. During Macintosh and Airtraq intubations with an injured C3–4 segment, despite a large difference in applied force between the 2 laryngoscopes, segmental extension (0.4° ± 2.7° vs 0.3° ± 3.3°, respectively; p = 0.8077) and anterior-posterior subluxation (0.3 ± 0.6 mm vs 0.0 ± 0.7 mm, respectively; p = 0.3203) did not differ.

CONCLUSIONS

The authors' hypotheses regarding the relationship between laryngoscope force and the motion of an injured cervical segment were not confirmed. Motion-force relationships (biomechanics) of injured cervical intervertebral segments during endotracheal intubation in cadavers are not predicted by the in vitro biomechanical behavior of isolated cervical segments. With the limitations inherent to cadaveric studies, the results of this study suggest that not all forms of cervical spine injury are at risk for pathological motion and cervical cord injury during conventional high-force line-of-sight intubation.

Device and Medication Preferences of Canadian Physicians for Emergent Endotracheal Intubation in Critically Ill Patients

OBJECTIVES

Various medications and devices are available for facilitation of emergent endotracheal intubations (EETIs). The objective of this study was to survey which medications and devices are being utilized for intubation by Canadian physicians.

METHODS

A clinical scenario-based survey was developed to determine which medications physicians would administer to facilitate EETI, their first choice of intubation device, and backup strategy should their first choice fail. The survey was distributed to Canadian emergency medicine (EM) and intensive care unit (ICU) physicians using web-based and postal methods. Physicians were asked questions based on three scenarios (trauma; pneumonia; heart failure) and responded using a 5-point scale ranging from "always" to "never" to capture usual practice.

RESULTS

The survey response rate was 50.2% (882/1,758). Most physicians indicated a Macintosh blade with direct laryngoscopy would "always/often" be their first choice of intubation device in the three scenarios (mean 85% [79%-89%]) followed by video laryngoscopy (mean 37% [30%-49%]). The most common backup device chosen was an extraglottic device (mean 59% [56%-60%]). The medications most physicians would "always/often" administer were fentanyl (mean 45% [42%-51%]) and etomidate (mean 38% [25%-50%]). EM physicians were more likely than ICU physicians to paralyze patients for EETI (adjusted odds ratio 3.40; 95% CI 2.90-4.00).

CONCLUSIONS

Most EM and ICU physicians utilize direct laryngoscopy with a Macintosh blade as a primary device for EETI and an extraglottic device as a backup strategy. This survey highlights variation in Canadian practice patterns for some aspects of intubation in critically ill patients.

Prehospital intubation for isolated severe blunt traumatic brain injury: worse outcomes and higher mortality

PURPOSE

Prehospital endotracheal intubation (ETI) for traumatic brain injury (TBI) is a controversial issue. The aim of this study was to investigate the effect of prehospital ETI in patients with TBI.

METHODS

Cohort-matched study using the US National Trauma Data Bank (NTDB) 2008-2012. Patients with isolated severe blunt TBI (AIS head ≥3, AIS chest/abdomen <3) and a field GCS ≤8 were extracted from NTDB. A 1:1 matching of patients with and without prehospital ETI was performed. Matching criteria were sex, age, exact field GCS, exact AIS head, field hypotension, field cardiac arrest, and the brain injury type (according PREDOT-code). The matched cohorts were compared with univariable and multivariable regression analysis.

RESULTS

A total of 27,714 patients were included. Matching resulted in 8139 cases with and 8139 cases without prehospital ETI. Prehospital ETI was associated with significantly longer scene (median 9 vs. 8 min, p < 0.001) and transport times (median 26 vs. 19 min, p < 0.001), lower Emergency Department (ED) GCS scores (in patients without sedation; mean 3.7 vs. 3.9, p = 0.026), more ventilator days (mean 7.3 vs. 6.9, p = 0.006), longer ICU (median 6.0 vs. 5.0 days, p < 0.001) and total hospital length of stay (median 10.0 vs. 9.0 days, p < 0.001), and higher in-hospital mortality (31.4 vs. 27.5 %, p < 0.001). In regression analysis prehospital ETI was independently associated with lower ED GCS scores (RC -4.213, CI -4.562/-3.864, p < 0.001) and higher in-hospital mortality (OR 1.399, CI 1.205/1.624, p < 0.001).

CONCLUSION

In this large cohort-matched analysis, prehospital ETI in patients with isolated severe blunt TBI was independently associated with lower ED GCS scores and higher mortality.

Postintubation Hypotension in General Anesthesia: A Retrospective Analysis

BACKGROUND

Postintubation hypotension (PIH) is an adverse event associated with poor outcomes in emergency department endotracheal intubations. Study objective was to determine the incidence of PIH and its impact on outcomes following tracheal intubation in a general anesthesia population.

METHODS

Structured chart audit of adult patients intubated for a vascular surgery procedure at a tertiary care center over a 3-year period. Outcomes included in-hospital mortality, extended intensive care unit length of stay (ICU LOS), and requirement for postoperative (postop) hemodialysis or mechanical ventilation.

RESULTS

Incidence of PIH was 60% (837 of 1395). Patients who developed PIH had increased mortality (8.8% PIH vs 5.2% no-PIH; P = .014), extended ICU LOS (7.9% PIH vs 2.0% no-PIH; P < .001), and postop mechanical ventilation requirement (20.7% PIH vs 3.8% no-PIH; P < .001). When controlling for confounding factors, PIH was associated with extended ICU LOS (odds ratio [OR] 2.55, 95% confidence interval [CI] 1.01-6.62, P = .049), postop ventilation (OR 2.43, 95% CI 1.27-4.74, P = .008), and a composite end point (OR 1.72, 95% CI 1.02-2.92, P = .043).

CONCLUSIONS

Development of PIH occurs in 60% of patients undergoing intubation for vascular surgery and was associated with adverse outcomes including extended ICU LOS and postop ventilation requirement.

The European guideline on management of major bleeding and coagulopathy following trauma: fourth edition

BACKGROUND

Severe trauma continues to represent a global public health issue and mortality and morbidity in trauma patients remains substantial. A number of initiatives have aimed to provide guidance on the management of trauma patients. This document focuses on the management of major bleeding and coagulopathy following trauma and encourages adaptation of the guiding principles to each local situation and implementation within each institution.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004 and included representatives of six relevant European professional societies. The group used a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were reconsidered and revised based on new scientific evidence and observed shifts in clinical practice; new recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated. This guideline represents the fourth edition of a document first published in 2007 and updated in 2010 and 2013.

RESULTS

The guideline now recommends that patients be transferred directly to an appropriate trauma treatment centre and encourages use of a restricted volume replacement strategy during initial resuscitation. Best-practice use of blood products during further resuscitation continues to evolve and should be guided by a goal-directed strategy. The identification and management of patients pre-treated with anticoagulant agents continues to pose a real challenge, despite accumulating experience and awareness. The present guideline should be viewed as an educational aid to improve and standardise the care of the bleeding trauma patients across Europe and beyond. This document may also serve as a basis for local implementation. Furthermore, local quality and safety management systems need to be established to specifically assess key measures of bleeding control and outcome.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. The implementation of locally adapted treatment algorithms should strive to achieve measureable improvements in patient outcome.

Intubation Biomechanics: Laryngoscope Force and Cervical Spine Motion during Intubation in Cadavers-Cadavers versus Patients, the Effect of Repeated Intubations, and the Effect of Type II Odontoid Fracture on C1-C2 Motion

BACKGROUND

The aims of this study are to characterize (1) the cadaver intubation biomechanics, including the effect of repeated intubations, and (2) the relation between intubation force and the motion of an injured cervical segment.

METHODS

Fourteen cadavers were serially intubated using force-sensing Macintosh and Airtraq laryngoscopes in random order, with simultaneous cervical spine motion recorded with lateral fluoroscopy. Motion of the C1-C2 segment was measured in the intact and injured state (type II odontoid fracture). Injured C1-C2 motion was proportionately corrected for changes in intubation forces that occurred with repeated intubations.

RESULTS

Cadaver intubation biomechanics were comparable with those of patients in all parameters other than C2-C5 extension. In cadavers, intubation force (set 2/set 1 force ratio = 0.61; 95% CI, 0.46 to 0.81; P = 0.002) and Oc-C5 extension (set 2 - set 1 difference = -6.1 degrees; 95% CI, -11.4 to -0.9; P = 0.025) decreased with repeated intubations. In cadavers, C1-C2 extension did not differ (1) between intact and injured states; or (2) in the injured state, between laryngoscopes (with and without force correction). With force correction, in the injured state, C1-C2 subluxation was greater with the Airtraq (mean difference 2.8 mm; 95% CI, 0.7 to 4.9 mm; P = 0.004).

CONCLUSIONS

With limitations, cadavers may be clinically relevant models of intubation biomechanics and cervical spine motion. In the setting of a type II odontoid fracture, C1-C2 motion during intubation with either the Macintosh or the Airtraq does not appear to greatly exceed physiologic values or to have a high likelihood of hyperextension or direct cord compression.

A hierarchical task analysis of cricothyroidotomy procedure for a virtual airway skills trainer simulator

BACKGROUND

Despite the critical importance of cricothyroidotomy (CCT) for patient in extremis, clinical experience with CCT is infrequent, and current training tools are inadequate. The long-term goal is to develop a virtual airway skills trainer that requires a thorough task analysis to determine the critical procedural steps, learning metrics, and parameters for assessment.

METHODS

Hierarchical task analysis is performed to describe major tasks and subtasks for CCT. A rubric for performance scoring for each task was derived, and possible operative errors were identified.

RESULTS

Time series analyses for 7 CCT videos were performed with 3 different observers. According to Pearson's correlation tests, 3 of the 7 major tasks had a strong correlation between their task times and performance scores.

CONCLUSIONS

The task analysis forms the core of a proposed virtual CCT simulator, and highlights links between performance time and accuracy when teaching individual surgical steps of the procedure.

Establishing a definitive airway in the trauma patient by novice intubators: A randomised crossover simulation study

BACKGROUND

Establishing a definitive airway, defined as a tube placed in the trachea with cuff inflated below the vocal cords, is standard of care in pre-hospital airway management of the trauma patient. However, in this setting, and using manual in-line stabilisation of the neck, success rate of intubation by inexperience providers is suboptimal. The use of supraglottic airway devices that allow blind tracheal intubation has been suggested as an alternative method by the Advanced Trauma Life Support (ATLS) programme of the American College of Surgeons. We aimed to compare intubation with the standard intubation technique (direct laryngoscopy [DL]) with blind intubation through an intubating-laryngeal mask airway (I-LMA) during manual in-line stabilisation of the neck.

MATERIALS AND METHODS

A randomised, crossover manikin study was performed with 29 emergency medical technicians undergoing training for paramedic status. Outcome measures were success rate in one intubation attempt, duration of intubation, and assessment of ease-of-use.

RESULTS

Study subjects had a higher success rate of tracheal intubation with I-LMA than with DL (27/29 vs. 18/29, p<0.025), and I-LMA was assessed as easier to use (4 vs. 3, p<0.0001). Longer duration of intubation was found with I-LMA compared to DL (54.2 vs. 42.8s, p<0.002). Success rate of correct placement of I-LMA within the airway was 28/29 (96.5%). Time to achieve correct placement of I-LMA within the airway was shorter than duration of tracheal intubation with DL (26.9 vs. 42.8s, p<0.0001).

CONCLUSIONS

Novice intubators had a higher success rate of intubation with I-LMA than with DL, but duration of intubation was longer with I-LMA. Time to achieve correct placement of I-LMA within the airway was shorter than duration of tracheal intubation with DL. Findings of this simulation study suggest that in the presence of manual in-line stabilisation of the neck, I-LMA-guided intubation is the preferred technique for novice intubators.