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
Category Archives: Kids
Acute Paediatrics
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
Identifying sick kids is still difficult
A systematic review to identify clinical features that have value in confirming or excluding the possibility of serious infection in children presenting to ambulatory care settings resulted in the calculation of likelihood ratios. Clinical features with a positive likelihood ratio of more than 5.0 were deemed red flags (ie, warning signs for serious infection); features with a negative likelihood ratio of less than 0.2 were deemed rule-out signs.
The features identified in several studies as red flags were :
- Cyanosis (+LR range 2.66-52.20)
- Rapid breathing (+LR 1.26-9.78)
- Poor peripheral perfusion (+LR 2.39-38.80)
- Petechial rash (+LR 6.18-83.70)]
In one primary care study the following were identified as strong red flags:
- Parental concern (+LR 14.40, 95% CI 9.30-22.10)
- Clinician instinct (+LR 23.50, 95 % CI 16.80-32.70)
Temperature of 40 degrees C or more had value as a red flag in settings with a low prevalence of serious infection.
What about ruling out serious illness?
Unfortunately, no single clinical feature had rule-out value but some combinations can be used to exclude the possibility of serious infection-for example, pneumonia is very unlikely (-LR 0.07, 95% CI 0.01-0.46) if the child is not short of breath and there is no parental concern.
An accompanying editorial sums up the challenge of paediatric emergency medicine in a nutshell:
“What is clear is that in 2010 we do not know how to effectively recognise or rule out severe disease in ill children and what is more, we do not even have a cohesive national or even global research strategy to address this problem.”
Diagnostic value of clinical features at presentation to identify serious infection in children in developed countries: a systematic review.
Lancet. 2010 Mar 6;375(9717):834-45
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
Best position for RIJV cannulation in kids
In a study of anaesthetised infants and children, the right internal jugular vein as assessed by ultrasonography was measured with the head in the neutral position, and then at 40 degrees and 80 degrees of rotation to the contralateral side. The 40 degree position resulted in an increase in IJV diameter but with less overlap with the carotid artery than the 80 degree position. The authors conclude that rotating the head 40 degrees to the left results in the best balance of increased IJV diameter versus overlap with the carotid.
Effects of head rotation on the right internal jugular vein in infants and young children
Anaesthesia Volume 65, Issue 3, Pages 272-276
Therapeutic hypothermia for newborns
In three randomised controlled trials encompassing 767 infants with hypoxic-ischaemic encephalopathy, induced moderate hypothermia for 72 hours significantly reduced the combined rate of death and severe disability, with a number needed to treat of nine (95% CI 5 to 25). Hypothermia increased survival with normal neurological function, with a number needed to treat of eight (95% CI 5 to 17), and in survivors reduced the rates of severe disability and cerebral palsy. The studies used different cooling methods and different target temperatures (33-34 deg C vs 34-35 deg C), suggesting the method of cooling itself is not important as long as therapeutic hypothermia is achieved.
Neurological outcomes at 18 months of age after moderate hypothermia for perinatal hypoxic ischaemic encephalopathy: synthesis and meta-analysis of trial data
BMJ. 2010 Feb 9;340:c363
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.
Paediatric ketamine sedation: adverse events
Records of 4252 patients aged 0-19 who received ketamine were reviewed for documented adverse events. Patients were all American Society of Anesthesiology Class I or II. 102 (2.4%) had an ‘adverse event’, defined as the occurrence of hypoxia by oxygen saturation lower than 93% on room air or clinical cyanosis, documentation of laryngospasm, airway obstruction, or apnea diagnosed clinically or by capnography, stridor, respiratory distress, or hypoventilation or hypercarbia as assessed by capnography. Cases with adverse events were compared with controls who had received ketamine without adverse events, but were not otherwise matched.
Of the adverse events, laryngospasm was documented to have occurred in 29/4252 cases (0.7%), hypoxia in 81/4252 (1.9%), and positive pressure ventilation was required in 33/4252 (0.8%). Intubation was required in one patient (0.023%). Compared with controls, patients with adverse events were more likely to have received IM, as opposed to IV, ketamine, although children who received IM ketamine were more likely to be younger than those who received IV ketamine (4.1 vs 7.9 years).
The retrospective design and other methodological limitations make it harder to draw conclusions other than what we know from existing literature, to which this large series adds: ketamine is given to a lot of kids with few adverse effects; larygnospasm is a real but infrequent occurrence that usually responds to simple manouevres; and intubation is extremely rarely required, but nevertheless may be necessary and therefore those physicians using ketamine should have advanced airway skills.
Serious Adverse Events During Procedural Sedation With Ketamine
Pediatr Emerg Care. 2009 May;25(5):325-8
Epinephrine and Dexamethasone in Children with Bronchiolitis
A multicentre double blind trial in 800 infants with bronchiolitis aged between 6 weeks and 12 months compared placebo with nebulised adrenaline, oral dexamethasone, or both. Only the combination led to a decrease in the primary endpoint of reduced hospital admission up to 7 days after enrollment, with an absolute risk reduction of 9% (from 26 to 17%). They also found an apparent benefit from combined therapy on their secondary outcomes: infants in the combined treatment group were discharged earlier from medical care and resumed quiet breathing and normal feeding sooner than did those in the placebo group. When the analysis was adjusted for multiple comparisons, the apparent benefit did not reach statistical significance, leading the authors to recommend further study.
Epinephrine and Dexamethasone in Children with Bronchiolitis
N Engl J Med. 2009 May 14;360(20):2079-89