Tag Archives: airway

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Australasian ED Airway Registry

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Managing the emergency airway is one of the most important and risky things we do. We have a responsibility to record, monitor, report and improve our performance.
In the US, the National Emergency Airway Registry has been running for over a decade and has significantly contributed to our airway knowledge base.
In the UK, the NAP4 audit provided fascinating and scary insight into complications of emergency airway management.
Pre-hospital registries have been developed, like Minh Le Cong’s Flying Doctor Emergency Airway Registry; and many of us are now contributing to the Airway Management Study in Physician Manned Helicopter Emergency Medical Services (AIRPORT) study.
Now there is an opportunity for Australasian emergency departments to contribute to a national audit.
Dr Toby Fogg FACEM, emergency physician at Royal North Shore Hospital in Sydney, who began the registry, explained in a recent Life in The Fast Lane response:


I have been running an airway registry in the ED at The Royal North Shore Hospital in Sydney for the last 2 years.

I presented the first 18 months of data at the ASM in Sydney last year and I must admit, they showed room for improvement!.

One of the many things we have subsequently done is introduced a Pre Intubation Checklist which I have published, along with our preliminary findings, at www.airwayregistry.org.au.

I am happy for people to download the file and use it as is, or with appropriate modifications.

Furthermore I would love to hear from anyone keen to undertake an Airway Registry in their own ED — a PDF of the data collection form we use is also on the website.

As the authors of the NAP4 study conclude, it is essential we all audit our practice of this potentially high risk procedure.

Dr Toby Fogg uses his C-MAC video laryngoscope to demonstrate the audit form


Background: Successful airway management is one of the cornerstones of care for critically ill or injured patients in the Emergency Department (ED). The risks of intubation are known to be higher in this environment than in the operating theatre (OT) yet there are no published data on airway management in an Australian ED.

Objectives: To describe the practice of intubation in the ED of a tertiary hospital in Australia, with particular emphasis on the number of attempts, adjuncts used, the seniority of staff involved and the rate of complications.

Methods: A prospective, observational study.

Results: Over the 18-month study period, 295 episodes of intubation occurred with a total of 345 attempts. Consultant supervision occurred in 69.8% of cases, registrars made the first attempt at intubation in 57.5% and SRMOs in 31.0% of the patients. 83.7% of the patients were intubated at the first pass with a further 13.0% intubated one the second attempt. This leaves 10 patients (3.4%) that required ≥3 attempts, 4 (1.4%) ≥4 attempts and 1 (0.4%) required a 5th attempt. Difficult laryngoscopy, as defined by Cormack and Lehane grade III or IV, occurred in 24% of the first attempts. Bougies were used in 36% of attempts, whilst a stylet in 35%. Video laryngoscopy was used in 47.5% of attempts. Complications occurred in 28%.

Discussion: The success rate within two attempts is comparable to the anaesthetic literature, and although high, the rate of complications is comparable to data from EDs overseas. The rate of difficult laryngoscopy, however, is surprisingly high. The study has prompted a significant review of airway training and management within the ED at Royal North Shore Hospital and the results of the interventions will be monitored.

The Royal North Shore Hospital Emergency Department Airway Registry. A Prospective Observational Study of Airway Management in a Tertiary Hospital Emergency Department in Sydney, Australia
Annesley N,Vassiliadis J, Kerry Hitos K, Fogg T
Emerg. Med. Australas. 24 (Suppl. 1):27-28

Study authors Toby Fogg and Nick Annesley demonstrate the 'Happiness Triad'

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Awake video laryngoscopy

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A nice study reminds of us the option of awake video laryngoscopy as an alternative to fibreoptic instrumentation of the airway. The study was done on healthy volunteers so we have no idea of the applicability to the patient group we would be interested in using this on – those with an anticipated difficult airway sufficiently stable to allow tolerance and preparation for this procedure. The videolaryngoscopy was performed with patients upright in a face-to-face position, with the laryngoscope inserted in the inverted handle-down (“tomahawk”) position (this is the way I remove fishbones using a direct laryngoscope and Magill’s forceps).
Visualization was faster with video laryngoscopy, and grade of view was similar in both groups. Cormack Lehane grading was used to assess view, whereas the POGO score (percentage of glottic opening) might have provided a better means of assessing which view is superior. The study did not evaluate endotracheal tube insertion.
Local anaesthesia was provided with 5 ml nebulised 4% lidocaine and weight-based doses of 4% lidocaine were then sprayed into the nose and oropharynx through a mucosal atomisation device to a maximum of 9 mg/kg. Oxymetazoline was applied nasally for the flexible fibreoptic laryngoscopy.


Study objectives: We compare laryngoscopic quality and time to highest-grade view between a face-to-face approach with the GlideScope and traditional flexible fiber-optic laryngoscopy in awake, upright volunteers.

Methods: This was a prospective, randomized, crossover study in which we performed awake laryngoscopy under local anesthesia on 23 healthy volunteers, using both a GlideScope video laryngoscopy face-to-face technique with the blade held upside down and flexible fiber-optic laryngoscopy. Operator reports of Cormack-Lehane laryngoscopic views and video-reviewed time to highest-grade view, as well as number of attempts, were recorded.

Results: Ten women and 13 men participated. A grade II or better view was obtained with GlideScope video laryngoscopy in 22 of 23 (95.6%) participants and in 23 of 23 (100%) participants with flexible fiber-optic laryngoscopy (relative risk GlideScope video laryngoscopy versus flexible fiber-optic laryngoscopy 0.96; 95% confidence interval 0.88 to 1.04). Median time to highest-grade view for GlideScope video laryngoscopy was 16 seconds (interquartile range 9 to 34) versus 51 seconds (interquartile range 35 to 96) for flexible fiber-optic laryngoscopy. A distribution of interindividual differences demonstrated that GlideScope video laryngoscopy was, on average, 39 seconds faster than flexible fiber-optic laryngoscopy (95% confidence interval 0.2 to 76.9 seconds).

Conclusion: GlideScope video laryngoscopy can be used to obtain a Cormack-Lehane grade II or better view in the majority of awake, healthy volunteers when an upright face-to-face approach is used and was slightly faster than traditional flexible fiber-optic laryngoscopy. However, flexible fiber-optic laryngoscopy may be more reliable
at obtaining high-grade views of the larynx. Awake, face-to-face GlideScope use may offer an alternative approach to the difficulty airway, particularly among providers uncomfortable with flexible fiber-optic laryngoscopy.

GlideScope Versus Flexible Fiber Optic for Awake Upright Laryngoscopy
Ann Emerg Med. 2012 Mar;59(3):159-64

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Airway lessons relearned

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A UK study examined all out-of-operating room intubations over a one month period in nine hospitals1.
Patients whose indication for tracheal intubation was cardiac arrest and who were intubated without the use of drugs were excluded from analysis, as were neonatal intubations.
Disappointing – but not surprising – findings were the lack of universally applied capnography and the use of propofol as the most commonly used induction agent. However more senior intubators were less likely to use propofol than more junior ones (who used it in 93% of intubations!), and the seniors were also more likely to use non-depolarising neuromuscular blocking drugs (NMBDs) than juniors.
The authors report that in seven (4%) patients, pre-oxygenation “was felt to be impossible“. I find it hard to imagine this situation unless RSI is being done on combative patients without prior sedation, which if this is the case makes me shudder.
The authors express their understandable concern over the absence of an alternative airway such as a laryngeal mask in 12% of cases.
Although the adverse event rate seems high, they point out that they used the term ‘adverse events’ rather than ‘complications’ as the events may not be directly attributable to the intubation. In other words, some patients may have been hypoxaemic or hypotensive to start with due to their underlying clinical problem.
I find this study interesting because the results are similar to those reported in a study I and my colleagues conducted a decade ago2, in which ICU intubations were shown to be more hazardous that ED intubations. This can be explained by the higher proportion of patients on ICU with shock and/or respiratory failure. On the other hand, ED patients more commonly required intubation for neurological presentations, with relatively stable cardiorespiratory physiology.
Take a look at the breakdown of cases in the recent study:

and compare this with our findings:

…this is why I have to argue when I hear it occasionally stated that ‘all ED airways are difficult airways’ – some are actually easy, in patients with long stable apnoea times who make great teaching cases.
The authors “speculate that the low rate of hypoxaemia and airway complications may be related to the high proportion of intubations undertaken by those with anaesthesia as a base speciality, and to the almost universal use of NMBDs.” They do not provide strong data to support the first half of their statement. The supplementary data available online indeed show that the majority of intubators were anaesthesia-based, but how their adverse event rates compare with those of the emergency physicians and paediatricians who also undertook intubations is not available.
I don’t want to detract from the important message Dr Bowles and colleagues are conveying: that the lessons from the 4th National Audit Project on major complications of airway management in the UK still need to be applied.
This paper is one aspect of the potentially life-saving work done by this team, which includes the intubation checklist they created.


BACKGROUND: Tracheal intubation is commonly performed outside the operating theatre and is associated with higher risk than intubation in theatre. Recent guidelines and publications including the 4th National Audit Project of the Royal College of Anaesthetists have sought to improve the safety of out-of-theatre intubations.

METHODS: We performed a prospective observational study examining all tracheal intubations occurring outside the operating theatre in nine hospitals over a 1 month period. Data were collected on speciality and grade of intubator, presence of essential safety equipment and monitoring, and adverse events.

RESULTS: One hundred and sixty-four out-of-theatre intubations were identified (excluding those where intubation occurred as part of the management of cardiac arrest). The most common indication for intubation was respiratory failure [74 cases (45%)]. Doctors with at least 6 month’s experience in anaesthesia performed 136 intubations (83%); consultants were present for 68 cases (41%), and overall a second intubator was present for 94 procedures (57%). Propofol was the most common induction agent [124 cases (76%)] and 157 patients (96%) received neuromuscular blocking agents. An airway rescue device was available in 139 cases (87%). Capnography was not used in 52 cases (32%). Sixty-four patients suffered at least one adverse event (39%) around the time of tracheal intubation.

CONCLUSIONS: Out-of-theatre intubation frequently occurs in the absence of essential safety equipment, despite the existing guidelines. The associated adverse event rate is high.

1. Out-of-theatre tracheal intubation: prospective multicentre study of clinical practice and adverse events
Br J Anaesth. 2011 Nov;107(5):687-92


BACKGROUND: Emergency rapid sequence intubation (RSI) performed outside the operating room on emergency patients is the cornerstone of emergency airway management. Complication rates are unknown for this procedure in the United Kingdom and the factors contributing to immediate complications have not been identified.

AIMS: To quantify the immediate complications of RSI and to assess the contribution made by environmental, patient, and physician factors to overall complication rates.

METHODS: Prospective observational study of 208 consecutive adult and paediatric patients undergoing RSI over a six month period.

RESULTS: Patients were successfully intubated by RSI in all cases. There were no deaths during the procedure and no patient required a surgical airway. Patient diagnostic groups requiring RSI are described. Immediate complications were hypoxaemia 19.2%, hypotension 17.8%, and arrhythmia 3.4%. Hypoxaemia was more common in patients with pre-existing respiratory or cardiovascular conditions than in patients with other diagnoses (p<0.01). Emergency department intubations were associated with a significantly lower complication rate than other locations (16.9%; p = 0.004). This can be explained by the difference in diagnostic case mix. Intubating teams comprised anaesthetists, non-anaesthetists, or both. There were no significant differences in complication rates between these groups.
CONCLUSIONS: RSI has a significant immediate complication rate, although the clinical significance of transient events is unknown. The likelihood of immediate complications depends on the patient’s underlying condition, and relevant diagnoses should be emphasised in airway management training. Complication rates are comparable between anaesthetists and non-anaesthetists. The significantly lower complication rates in emergency department RSI can be explained by a larger proportion of patients with comparatively stable cardiorespiratory function.

2. The who, where, and what of rapid sequence intubation: prospective observational study of emergency RSI outside the operating theatre
Emerg Med J. 2004 May;21(3):296-301 Free Full Text

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A big brain saves a little one

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Something I’ve been teaching for years – but never actually done – has been described in a case report from Oman.
A 2 year old child suffered a respiratory arrest due to an inhaled foreign body, which led to a bradyasystolic cardiac arrest. She was intubated by the resuscitation team who could not achieve any ventilation through the tube. The tube was removed and reinserted by an ‘expert’ (there is no mention of capnometry, for what it’s worth) and the same problem persisted.
The life-saving manouevre was to insert the tracheal tube further down into the right main bronchus and then withdraw to the trachea. This forced the obstructing object distally so that one-lung ventilation was then possible, resulting in return of spontaneous circulation and oxygen saturations in the mid-80’s. The object – a broken piece of plastic – was removed bronchoscopically and happily the child made an uneventful recovery.
Is this technique in your list of life-saving tricks? Hopefully, it is now.
A child is alive because a doctor was able to ‘think outside the guidelines’ in an incredibly high pressure situation. Rigid adherence to ACLS procedures here would have been futile. The guidelines save lives, but a few more can be saved when care can be individualised to the clinical situation by a thinking clinician.
Well done Dr Mishra and colleagues.

Sudden near-fatal tracheal aspiration of an undiagnosed nasal foreign body in a small child
Emerg Med Australas. 2011 Dec;23(6):776-8
[And here’s something else to consider if you have no airway equipment with you and your basic choking algorithm isn’t working]

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Emergency percutaneous airway

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An excellent thorough review of emergency needle and surgical cricothyroidotomy – collectively described as ’emergency percutaneous airway’ – reveals a number of pearls.
Regarding anatomy:

  • The cricothyroid menbrane has an average height of 10 mm and a width of 11 mm
  • Transverse incision in the lower half of the cricothyroid membrane is recommended to avoid the cricothyroid arteries and the vocal cords

Regarding oxygenation / ventilation via a cricothyroid needle:

  • High pressure source ventilation via a needle (eg. by Sanders injector or Manujet) may cause laryngospasm, so a neuromuscular blocking agent should be considered
  • Barotrauma may result from an obstructed upper airway, so efforts should be made to maintain upper airway patency where possible (eg. with a supraglottic airway)
  • A device has been manufactured that provides suction-generated expiratory ventilation assistance (using oxygen flow and the Bernoulli principle) – the Ventrain
  • The Fourth National Audit Project reported a much lower success rate and described several complications of attempted re-oxygenation via a narrow-bore cricothyroidotomy
  • Where there is no kink-resistant cannula or suitable high-pressure source ventilation device readily available, it is probably safer to perform a wide-bore cannula puncture or surgical cricothyroidotomy.

Wide-bore cannula-over trocar devices:

  • Include the Quicktrach II and Portex cricothyroidotomy kit
  • Sometimes require considerable force to push the device through the cricothyroid membrane, risking compression of the airway and damage or perforation of the posterior tracheal wall.

Seldinger cricothyroidotomy kits:

  • Separate the puncture and dilatation steps, minimising the risk of trauma
  • Include the Melker emergency cricothyroidotomy set, available in sizes 3.0–6.0 mm ID
  • Tend to be preferred by anaesthetists over the surgical and wide-bore cannula-over-trocar techniques
  • Seldinger technique in human cadavers and manikin studies by those well trained, inexperienced operators have low success rates and a long performance time

What about after?

  • High-pressure source ventilation may aid subsequent intubation by direct laryngoscopy as bubbles may be seen emerging from the glottis.
  • The Seldinger technique has been recommended to convert a narrow-bore cannula into a cuffed wide-bore cricothyroidotomy
  • While conversion of cricothyroidotomy to tracheostomy within 72 h has been advocated because of the increased risk of developing subglottic stenosis with prolonged intubation through the cricothyroid membrane, this risk may be much lower than previously believed
  • The risk of conversion, although less well examined, may also be appreciable

Which technique is best?

  • The recent NAP4 audit reported a success rate of only 37% for narrow-bore cannula-over-needle cricothyroidotomy, 57% for wide-bore cannula techniques and 100% for surgical cricothyroidotomy
  • Simulation studies show conflicting results about whether seldinger or surgical technique is faster.
  • Reported success rates of the different techniques (in simulations) also vary widely and range for surgical cricothyroidotomy from 55% to 100%, for wide-bore cannula-over-trocar from 30% to 100%, and for Seldinger technique from 60% to 100%.

The one area of some consensus is that conventional (low-pressure source) ventilation should not be used with a narrow-bore cannula; a high-pressure oxygen source and a secure pathway for the egress of gas are both mandatory to achieve adequate ventilation.
Complications may be related to technique:

  • Complications of narrow-bore cannula techniques are ventilation-related and include barotrauma, subcutaneous emphysema, pneumothorax, pneumomediastinum and circulatory arrest due to impaired venous return; Cannula obstruction due to kinking also occurs.
  • Seldinger technique may be complicated by kinking of the guidewire, which increases the risk of tube misplacement
  • Bleeding and laryngeal fracture may complicate the surgical method, and long-term complications include subglottic stenosis, scarring and voice changes.

Equipment and strategies for emergency tracheal access in the adult patient
Anaesthesia. 2011 Dec;66 Suppl 2:65-80

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Listen over the neck when inflating ETT cuff

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This interesting study introduces a novel technique for guiding the inflation of tracheal tube cuffs to avoid excessive cuff pressures: listening with a stethoscope over the thyroid cartilage and inflating the cuff until breath sounds change from harsh to soft.


Tracheal tube cuffs are commonly inflated to pressures exceeding the recommended upper limit of 30 cmH2O. We evaluated whether a stethoscope-guided method of cuff inflation results in pressures within the recommended range. Patients were randomly assigned to receive one of two methods of cuff inflation. In the standard ‘just seal’ group, air was introduced into the tracheal cuff until the audible leak at the mouth disappeared. In the stethoscope-guided group, air was introduced into the cuff until a change from harsh to soft breath sounds occurred, whilst listening with a stethoscope bell placed over the thyroid cartilage. Twenty-five patients were recruited
to each group. The median (IQR [range]) cuff pressure in the ‘just seal’ group was 34 (28–40 [18–49]) cmH2O, and in the stethoscope-guided group was 20 (20–26 [16–28]) cmH2O,
p < 0.0001. The stethoscope-guided method of tracheal tube cuff inflation is a novel, simple technique that reliably results in acceptable tracheal cuff pressures.

Clinical evaluation of stethoscope-guided inflation of tracheal tube cuffs
Anaesthesia. 2011 Nov;66(11):1012-6

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Make space for pre-hospital intubation

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“Control your environment – don’t let it control you” is a reliable adage for pre-hospital providers, and its adherence can assist in in-hospital resuscitation too. Commanding control of ones space is a skill demonstrated by more seasoned paramedics compared with novices and the requirement, where possible, for 360 degrees of access around a patient is included in some Standard Operating Procedures for pre-hospital rapid sequence intubation.

Brett Rosen MD controlling space in the field

Evidence for this approach is now further supported by a study demonstrating that limited surrounding space on scene was a significant risk factor for difficult pre-hospital intubation by European EMS physicians.
Other predisposing factors for difficult prehospital intubation included obesity and a short neck.


OBJECTIVES:For experienced personnel endotracheal intubation (ETI) is the gold standard to secure the airway in prehospital emergency medicine. Nevertheless, substantial procedural difficulties have been reported with a significant potential to compromise patients’ outcomes. Systematic evaluation of ETI in paramedic operated emergency medical systems (EMS) and in a mixed physician/anaesthetic nurse EMS showed divergent results. In our study we systematically assessed factors associated with difficult ETI in an EMS exclusively operating with physicians.

METHODS:Over a 1-year period we prospectively collected data on the specific conditions of all ETIs of two physician staffed EMS vehicles. Difficult ETI was defined by more than 3 attempts or a difficult visualisation of the larynx (Cormack and Lehane grade 3, or worse). For each patient ETI conditions, biophysical characteristics and factors of the surrounding scene were assessed. Additionally, physicians were asked whether they had expected difficult ETI in advance.

RESULTS:Out of 3979 treated patients 305 (7.7%) received ETI. For 276 patients complete data sets were available. The incidence of difficult ETI was 13.0%. In 4 cases (1.4%) ETI was impossible, but no patient was unable to be ventilated sufficiently. Predicting conditions for difficult intubation were limited surrounding space on scene (p<0.01), short neck (p<0.01), obesity (p<0.01), face and neck injuries (p<0.01), mouth opening<3cm (p<0.01) and known ankylosing spondylitis (p<0.01). ETI on the floor or with C-spine immobilisation in situ were of no significant influence. The incidence of unexpected difficult ETI was 5.0%.
CONCLUSIONS: In a physician staffed EMS difficult prehospital ETI occurred in 13% of cases. Predisposing factors were limited surrounding space on scene and certain biophysical conditions of the patient (short neck, obesity, face and neck injuries, and anatomical restrictions). Unexpected difficult ETI occurred in 5% of the cases.

Difficult prehospital endotracheal intubation – predisposing factors in a physician based EMS
Resuscitation. 2011 Dec;82(12):1519-24

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Saving Lives Through Failure

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Think about what you would do if faced with the following situation:

You sedate and paralyse a patient with severe injuries in order to intubate them. You are unable to intubate due to a poor view and massive orofacial haemorrhage. An iGel provides temporary oxygenation while you prepare for a surgical airway.

Your first surgical airway attempt fails due to insertion of the bougie through a false (too superficial) passage. You spot your mistake and re-do the procedure successfully with a deeper incision. The patient’s airway is secure and there is good oxygenation and ventilation.

You discover that a colleague has videoed the procedure on his iPhone. However he only captured the first, unsuccessful attempt. The patient is not identifiable in the close up video. It’s late at night and only he and you know of the existence of the video. He asks you what you want him to do with it.



Do you…
(a) Ask your colleague to delete the video?
(b) Watch the video with him and look for learning points, and then delete it?
(c) Ask him for a copy of it and request that he doesn’t show it to anyone else?
(d) Other course of action
Consider your course of action given this situation, and then click below to reveal what my colleague did recently in exactly the same scenario…
[EXPAND What did he do?]
(d) He did something else entirely: he got a copy of the video, burned it onto a CD, and left it on his boss’s desk!

It takes a certain kind of practitioner to risk embarrassment and criticism in the pursuit of the greater educational good.

He had already ascertained what he would need to do differently next time, so had nothing personal to gain from his chosen action.

Instead, he believed that sharing the video would help prevent his colleagues from repeating the same mistake, and help his supervisors review their cricothyroidotomy training in order to better prepare their team for the procedure. Ultimately, this gesture was directed towards the good of our patients.

His actions may have saved more than one life that evening.

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Preoxygenation and Prevention of Desaturation

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This paper is an excellent review article citing the cogent relevant evidence for optimal preoxygenation prior to RSI in the critically ill patient. The evidence has been interpreted with pertinent recommendations by two of the world’s heavy hitters in emergency medicine – Scott Weingart and Rich Levitan. If you can get a full text copy of the paper, laminate Figure 3 (‘Sequence of Preoxygenation and Prevention of Desaturation‘) and stick it to the wall in your resus bay!
The points covered include:

  • Why preoxygenate? Preoxygenation extends the duration of safe apnoea and should be considered mandatory, even in the crashing patient.
  • Standard non-rebreather facemasks set to the highest flow rate of oxygen possible should be used.
  • Allow 8 vital capacity breaths for co-operative patients or 3 minutes for everyone else.
  • Increasing mean airway pressure by CPAP/NIV or PEEP valves improves preoxygenation. However caution should be used in hypovolaemic shocked patients (decreased venous return) and should be reserved for patients who cannot preoxygenate >93-95% with high FiO2.
  • 20-degree head up or reverse Trendelenburg (in suspected trauma) improves pre oxygenation.
  • Apnoeic diffusion oxygenation can extend safe duration of apnoea after the RSI. Set nasal cannulae at 15L/min and leave on during intubation attempts. Ensure upper airway patency (ear to sternal notch and jaw thrust).
  • Active ventilation during onset of muscle relaxation should be assessed on a case by case basis and reserved for patients at high risk of desaturation (6-8 breaths per minute slowly, TV 6-7ml/kg).
  • If there is a high risk of desaturation rocuronium (1.2 mg/kg) may provide a longer duration of safe apnoea than suxamethonium with similar onset time.

Preoxygenation and Prevention of Desaturation During Emergency Airway Management
Ann Emerg Med. 2011 Nov 1. [Epub ahead of print]
[EXPAND Abstract]

Patients requiring emergency airway management are at great risk of hypoxemic hypoxia because of primary lung pathology, high metabolic demands, anemia, insufficient respiratory drive, and inability to protect their airway against aspiration. Tracheal intubation is often required before the complete information needed to assess the risk of periprocedural hypoxia is acquired, such as an arterial blood gas level, hemoglobin value, or even a chest radiograph. This article reviews preoxygenation and peri-intubation oxygenation techniques to minimize the risk of critical hypoxia and introduces a risk-stratification approach to emergency tracheal intubation. Techniques reviewed include positioning, preoxygenation and denitrogenation, positive end expiratory pressure devices, and passive apneic oxygenation.

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