Tag Archives: Tips

A human suction unit for choking

A case is described of a 12 month old who completely obstructed her airway from an inhaled plastic ketchup container. As she did not improve with backslaps or chest thrusts her father, a physician, suctioned her airway using his own mouth (intermittently spitting out secretions) until the obstruction was relieved and the object removed. Something to think about if you’re at the end of your own child’s choking algorithm and you have no airway equipment with you.

Maneuver for the recovery of a foreign body causing a complete airway obstruction: illustrative case.
Pediatr Emerg Care. 2010 Jan;26(1):39-40

Is ETT muck delaying weaning?

Organised secretions can build up in a tracheal tube. This increases airway resistance so during a spontaneous breathing trial in a patient being considered for extubation the patient may have increased work of breathing and unfairly fail the trial, delaying extubation.

How can you spot it? Increased airways resistance can increase peak airway pressure. However inspiratory plateau pressure will not be affected (obtained by performing an inspiratory hold). Identifying a big difference between peak and plateau pressures should prompt a search for increased airway resistance, which includes a narrowed tracheal tube lumen. The amount of accumulated secretion is not necessarily related to the duration of intubation.

Increases in endotracheal tube resistance are unpredictable relative to duration of intubation
Chest 2009; 136:1006-1013

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

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

Take bloods before giving Lipid Rescue

Intralipid therapy is recommended for local anaesthetic toxicity and in some overdoses. After large doses of Intralipid, the results of blood tests may be difficult to analyse, delayed, or spuriously abnormal. If possible, all blood tests should be taken before the administration of Intralipid. While laboratories will readily identify significant lipaemia, communication about the presence of Intralipid is important. In one case, the inability to obtain a haemoglobin result led to delay in the identification of haemorrhage which was the cause of deterioration initially thought to be local anaesthetic toxicity.

Possible side effects of Intralipid rescue therapy
Anaesthesia 2010;65(2):210-11

Securing infant tracheal tubes

Small head movements can cause significant tracheal tube migration in infants unless the tube is adequately secured.

Many use a version of the Melbourne strapping method:

1. Equipment required: Silk suture (cut off needle), ‘Cavilon’, elastoplast cut into 3 strips – 2 trouser shaped, and one with a 4cm hole in middle.

2. Apply Cavilon to face (a barrier film to protect the skin) over the area shown by red blobs in the picture.

3. Tie the suture around the tracheal tube. This marks the tube position at the mouth, and allows the tube to be held in place during fixation and when the tapes are later changed.

Pull the two ends taut across both cheeks.

3. While the suture is being pulled taut, place the first ‘trousers’ so that the undivided end is along the cheek (over the tape). The lower ‘leg’ is placed between the lower lip and the chin.

The upper ‘leg’ is folded back on itself to make it easier to removed at a later stage. It is then wound around the tracheal tube

4. The second set of ‘trousers’ is then applied on the other side, once again with the undivided end over the cheek and suture.

The upper ‘leg’ goes between the nose and the top lip and the lower leg is wound around the tracheal tube.

5. Finally the third piece of elastoplast is placed so that the tube goes through the hole

and applied over the other tapes. If there is an orogastric tube this should also go through the hole. The tube is now secure for transfer.

Some causes of a raised lactate

A high serum lactate does not necessarily mean a bad prognosis: it all depends on the cause.

I made this diagram as a mnemonic for the causes of high lactates:

Additional information added 1st June 2011
: One cause of an elevated lactate may be artefactual, secondary to interference with the assay (used on ABG machines) by ethylene glycol. The assay may also be subject to interference from certain drugs at toxic levels such as isoniazid, acetaminophen and thiocyanate. This information is from the Renal Fellow Network.

Ionised hypocalcaemia after ROSC

Ionised hypocalcaemia has been observed post-cardiac arrest in previous studies. Investigators in Utah induced VF in a swine model and resuscitated them back to spontaneous circulation1. Ionised hypocalcaemia was associated with hypotension and impaired LV function, and its treatment with a calcium infusion resulted in improved mean arterial pressure and left ventricular stroke work.

Although iv calcium is not recommended as a blind treatment in cardiac arrest, in part due to concerns about exacerbating cellular injury, this study reminds us that the treatment of ionised hypocalcaemia is important, and may be necessary after ROSC.

1. Hypocalcemia following resuscitation from cardiac arrest revisited
Resuscitation 2010 Jan;81:117–122

Differentiating arteries from veins

In a letter to Critical Care Medicine, ultrasound legend Michael Blaivas reminds readers that during ultrasound-guided central venous catheterisation, an additional technique for differentiating the common carotid artery from the internal jugular vein: pulse-wave doppler.

Image reproduced with kind permission of Dr Blaivas

Blaivas states: “The left panel shows a classic arterial tracing from the common carotid artery with a normal velocity. The right panel shows the vessel of choice on the same patient: the right internal jugular vein. The image shows a slightly chaotic venous tracing from the jugular. This a common appearance and is markedly different from the waveform of the carotid.”

Posterior vessel wall penetration by needles during internal jugular vein central catheter placement using ultrasound guidance: is that a real danger? Author’s Reply.
Crit Care Med. 2010 Feb;38(2):736-7

Neonatal Emergencies

‘THE MISFITS’ is a popular mnemonic to assist in identifying the cause of critical illness in the neonatal period.

T = Trauma (Accidental and Non Accidental)
H = Heart Disease, Hypovolemia, Hypoxia
E = Endocrine (Congenital Adrenal Hyperplasia, Thyrotoxicosis)
M = Metabolic (Electrolyte Imbalance)
I = Inborn Errors of Metabolism
S = Sepsis (Meningitis, Pneumonia, UTI)
F = Formula Mishaps (Under or Over dilution)
I = Intestinal Catastrophes (Intussusception, Volvulus, Necrotizing Enterocolitis)
T = Toxins / Poisons
S = Seizures

From: Tonia J. Brousseau, Ghazala Q. Sharieff Neonatal Emergencies
http://cme.medscape.com/viewarticle/557824 accessed 29/12/09