An abstract from the The National Association of EMS Physicians® 2010 Scientific Assembly published in a Supplement of Prehospital Emergency Care describes a study comparing cadaveric intubation success rates by paramedics in different positions: on the floor, on an elevated stretcher, and in a simulated ambulance. Despite less experience intubating on an elevated stretcher, the participants had increased first-attempt success in the elevated stretcher position compared with the back of the ambulance and the floor (although in the latter case this lacked statistical significance). Position is everything! In our HEMS service we prefer a lowered stretcher to either on the ground or in the ambulance – it would be nice to see this position studied one day too.
Pre-hospital intubation: patient position does matter
Prehospital Emergency Care 2010;14(Suppl 1):9
Tag Archives: procedures
LMA for newborn resuscitation
An observational study of near term infants (34 weeks gestation to 36 weeks and 6 days) born in an Italian centre over a 5 year period showed that nearly 10% of near-term infants needed positive pressure ventilation at birth, confirming that this group of patients is more vulnerable than term infants. Most were able to be managed with either bag-mask ventilation (BMV) or with a size 1 laryngeal mask airway (LMA). Of the 86 infants requiring PPV, 36 (41.8%) were managed by LMA, 34 (39.5%) by BMV and 16 (18.6%) by tracheal intubation. Why not slap a tiny LMA on your neonatal resuscitation cart – it could come in handy!
Delivery room resuscitation of near-term infants: role of the laryngeal mask airway
Resuscitation. 2010 Mar;81(3):327-30
Is defibrillation an electric threat for bystanders?
No rescuer or bystander has ever been seriously harmed by receiving an inadvertent shock while in direct or indirect contact with a patient during defibrillation. New evidence suggests that it might even be electrically safe for the rescuer to continue chest compressions during defibrillation if self-adhesive defibrillation electrodes are used and examination gloves are worn. This paper reviews the existing evidence, but warns more definite data are needed to make absolutely sure that there is no risk before defibrillation safety recommendations are changed.
Is external defibrillation an electric threat for bystanders?
Resuscitation. 2009 Apr;80(4):395-401
Oblique view for IJV cannulation
Simple really. Using the transverse view the needle tip can be hard to visualise. In the longitudinal view you don’t see the carotid artery. Applying an oblique view with an obliquely oriented needle “uses the superiority of the short axis view by visualizing all of the important surrounding structures (artery and vein) in an oblong view while allowing continuous real-time visualization of the long axis of the needle, therefore providing a larger, more easily visible target with a brighter more easily recognized needle.” The ultrasound probe is orientated at approximately 45° so that the medial end of the ultrasound probe aligns with the patient’s contralateral nipple or shoulder.
The oblique view: an alternative approach for ultrasound-guided central line placement
J Emerg Med. 2009 Nov;37(4):403-8
Full Text Article
10 ml syringe for Valsalva manoeuvre
Previous studies have suggested the following are necessary for a successful Valsalva manoeuvre with maximum vagal effect:
- Supine posturing
- Duration of 15 seconds
- Pressure of 40 mmHg (with an open glottis)
One popular method of generating a Valsalva Manoeuvre is to get the patient to blow into a syringe in an attempt to move the plunger. Different syringe sizes were tested. A 10ml (Terumo) syringe was best
The 10 mL syringe is useful in generating the recommended standard of 40 mmHg intrathoracic pressure for the Valsalva manoeuvre
Emerg Med Australas. 2009 Dec;21(6):449-54
Ketamine and procedural success
There is a myth that increased muscular tone caused by ketamine leads to an increased failure rate of joint manipulations when this agent is used for procedural sedation in the ED. This is neither borne out by the published evidence nor our own experience of a series of cases, which have been presented by Louisa Chan at a former (UK) College of Emergency Medicine Conference. At the Australasian College of Emergency Medicine Annual Scientific Conference in Melbourne these data were presented by A/Professor Taylor’s team in Victoria, which provide evidence that procedural failure rate is in fact lower with ketamine than with other commonly used sedatives. Here is the abstract reproduced with the kind permission of A/Prof Taylor:
Failure to successfully complete a procedure following emergency department sedation
DMcD Taylor1,2 for the Emergency Department Sedation Study Investigators
1Austin Health; 2University of Melbourne, Melbourne, Australia
Aims: To determine the nature and incidence of, and factors contributing to, failure to successfully complete a procedure fol- lowing sedation in the ED
Methods: Eleven Australian ED enrolled consecutive adult and paediatric patients between January 2006 and December 2008. Patients were included if a sedative drug was administered for an ED procedure. Data collection was prospective and employed a specifically designed form.
Results: Two thousand six hundred and twenty three patients were enrolled (60.3% male, mean age 39.2 years). Failure to successfully complete the procedure occurred in 148 (5.6%) cases. Most failures occurred with attempted reductions of fractured/dislocated shoulders (35 cases), hips (32), ankles (21) and elbows (14). However, failure rates were highest among fractured/dislocated hips (18.5%), digits (13.7%), femurs (11.1%), mandibles (10.2%) and elbows (9.3%). Failure rates for residents/registrars (5.9%), consultants (5.6%) and nurse practitioners (5.9%) did not differ (P = 0.92). Overall, failure rates for the various drugs (used alone or in combina- tion) did not differ (P = 0.07). However, ketamine (used alone or in combination) was associated with a much lower failure rate (2.9%) than all other sedation drugs used (midazolam 5.8%, propofol 6.5%, fentanyl 6.9%, nitrous oxide 7.1%, and morphine 7.8%).
Conclusion: Procedural failure is uncommon although some pro- cedures are at higher risk, especially dislocated hip reduction. Failure rates do not appear to be affected by the designation of the operator or the sedative drug used. However, ketamine use is associated with lower failure rates. For those procedures at higher risk of failure, the provision of optimal conditions (spe- cialist unit assistance, venue, drug selection) may minimise failure rates.
Emergency Medicine Australasia 2010;22(S1):A52-3
End tidal CO2 and procedural sedation
One hundred and thirty-two adults underwent propofol sedation in the emergency department and were randomised into a group in which treating physicians had access to the capnography and a blinded group in which they did not. All patients received supplemental oxygen (3 L/minute) and opioids greater than 30 minutes before. Propofol was dosed at 1.0 mg/kg, followed by 0.5 mg/kg as needed.
Hypoxia (defined as SpO2 less than 93%) was observed in 17 of 68 (25%) subjects with capnography and 27 of 64 (42%) with blinded capnography (p=.035; difference 17%; 95% confidence interval 1.3% to 33%). Capnography identified all cases of hypoxia before onset (sensitivity 100%; specificity 64%), with the median time from capnographic evidence of respiratory depression to hypoxia 60 seconds (range 5 to 240 seconds).
The journal comments: ‘this study provides compelling evidence that capnography can aid in the detection of respiratory depression and reduce hypoxia during procedural sedation.’
However in an accompanying article outlining a pro-con debate for introducing capnography as standard practice in ED procedural sedation, the point is made that the safety benefit purported in this and similar studies is decreased hypoxemia, according to thresholds ranging from 90% to 95%, lasting from 5 to 15 seconds. In the clinical context, many of these events are self-limiting or resolve with minimal interventions such as airway repositioning or supplemental oxygen, and other more clinically relevant outcomes are rarely examined (perhaps due to the rarity of genuinely adverse events in ED procedural sedation by emergency physicians).
Does end tidal CO2 monitoring during emergency department procedural sedation and analgesia with propofol decrease the incidence of hypoxic events? A randomized, controlled trial
Ann Emerg Med. 2010 Mar;55(3):258-64
Difficult mask ventilation
A comprehensive review of difficult mask ventilation (DMV) reports that the incidence of DMV varies widely (from 0.08% to 15%) depending on the criteria used for its definition. It reminds us that the independent predictors of DMV are:
- Obesity
- Age older than 55 yr
- History of snoring
- Lack of teeth
- The presence of a beard
- Mallampati Class III or IV
- Abnormal mandibular protrusion test
The review also points out that DMV does not automatically mean difficult laryngoscopy, although it does increase its likelihood.
In addition to positioning, oral and nasal adjuncts, two person technique, and jaw thrust, the application of 10 cmH20 CPAP may help splint open the airway and reduce the difficulty of mask ventilation in some patients.
Difficult mask ventilation
Anesth Analg. 2009 Dec;109(6):1870-80
Causes of DMV:
1) Technique-related
1. Operator: Lack of experience
2. Equipment
a. Improper mask size
b. Difficult mask fit: e.g., beard, facial anomalies, retrognathia
c. Leakage from the circuit
d. Faulty valve
e. Improper oral/nasal airway size
3. Position: Suboptimal head and neck position
4. Incorrectly applied cricoid pressure
5. Drug related
a. Opioid-induced vocal cord closure
b. Succinylcholine-induced masseter rigidity
c. Inadequate depth of anesthesia
d. Lack of relaxation?
2) Airway-related
1. Upper airway obstruction
a. Tongue or epiglottis
b. Redundant soft tissue in morbid obesity and sleep
apnea patients
c. Tonsillar hyperplasia
d. Oral, maxillary, pharyngeal, or laryngeal tumor
e. Airway edema e.g., repeated intubation attempts,
trauma, angioedema
f. Laryngeal spasm
g. External compression e.g., large neck masses and
neck hematoma
2. Lower airway obstruction
a. Severe bronchospasm
b. Tracheal or bronchial tumor
c. Anterior mediastinal mass
d. Stiff lung
e. Foreign body
f. Pneumothorax
g. Bronchopleural fistula
3) Severe chest wall deformity or kyphoscoliosis restricting chest expansion
Cricoid pressure squashes kids' airways
A bronchoscopic study of anaesthetised infants and children receiving cricoid pressure revealed the procedure to distort the airway or occlude it by more than 50% with as little as 5N of force in under 1s and between 15 and 25N in teenagers. Therefore forces well below the recommended value of 30 N will cause significant compression/distortion of the airway in a child
Effect of cricoid force on airway calibre in children: a bronchoscopic assessment
Br J Anaesth. 2010 Jan;104(1):71-4
Minimising risks of suprapubic catheter insertion
The UK National Health Service’s National Patient Safety Agency published a report entitled Minimising risks of suprapubic catheter insertion ‘, reporting three incidents of death and seven causing severe harm from suprapubic catheter placement between September 2005 and June 2009, nine of which involved bowel perforation. There were also 249 other incidents reported relating to suprapubic catheters causing lesser degrees of harm. They issue the following recommendations under the title ‘For IMMEDIATE ACTION by medical directors in acute and community hospitals (NHS and Independent Sector). Deadline for ACTION COMPLETE is 29 April 2010’:
- Information about the risk of this procedure is immediately distributed to all staff who may insert or request the insertion of a suprapubic catheter.
- A named lead for training is identified and a training plan developed.
- Local guidelines/policies are reviewed or developed in the light of this report and forthcoming British Association of Urological Surgeons (BAUS) standards.
- Ultrasound is used wherever possible to visualise the bladder and guide the insertion of the catheter. There should be ultrasound machines available in the relevant areas and staff trained in their use.
- Local incident data relating to suprapubic catheterisation is reviewed, appropriate action is taken and staff are encouraged to report further incidents and to take part in the BAUS national clinical audit.
Minimising risks of suprapubic catheter insertion
National Patient Safety Agency