When I was preparing for my talk at smaccGOLD I contacted the wonderful Ross Fisher, a Paediatric Surgeon, to ask him for some tips; what did he wish all ED docs and GPs knew about paediatric surgical patients?
He was kind enough to provide me with a list of hints, tips and pearls of wisdom – but in his alter ego as presentation guru I know he will be the least disappointed of all when I admit that most of them didn’t make it into my talk. If you haven’t already grasped this, there is nothing in the world drier than a talk which consists of a list of facts.
BUT – I really wanted to share some of his wisdom and my daily #PaedsTips tweet on Saturday morning was a Paediatric EM truth I sometimes forget that junior doctors don’t appreciate.
Since this started an international twitter conversation, here’s a little bit of wisdom on vomiting in kids.
We have to take good histories; but the quality of the information they provide is at risk because we fail to understand that by the time we leave medical school we spend the majority of our working lives speaking a different language from our patients and carers. Sometimes vomiting in kids is of great significance. Most of the time, it isn’t.
What do parents mean?
Usually, parents mean yellow vomit – any vomitus that isn’t recognisable food (“It was just bile, doctor”). There’s a lay perception that “bile” means “stomach contents”.
What do we mean
Healthcare professionals mean bile, the cooked-spinach-green substance produced by the gallbladder.
Or, at least, that’s what they should mean. Worryingly, they are often confused about what constitutes bilious vomiting as this (free to access) study shows (thanks to Damian Roland and David King for flagging this one up). There’s another great free to access paper here, this time set in a neonatal unit not too far from Virchester and comparing healthcare professionals’ and parents’ interpretations of gastric aspirates, showing that pretty much any vomitus can be (mis)interpreted as bile-stained, depending on who is asked.
What does bilious vomiting mean?
In newborns and infants, bilious vomiting represents intestinal obstruction and is a surgical emergency. There are a variety of causes – duodenal atresia, midgut malrotation and volvulus, jejunoileal atresia, meconium ileus (which has its own subset of causes) and necrotising enterocolitis are a few. Most ED clinicians don’t need to know much detail about this other than that green vomitus in a neonate – with or without abdominal distension – warrants a paediatric (or neonatal) surgical review urgently. These babies are very sick (unwell) and may need access (IV or IO) with fluid replacement and NG placement (free drainage to reduce further vomiting). If you want to read more about bilious vomiting in neonates, there’s a nice open access review here.
Very occasionally a baby with intestinal obstruction will have yellow vomitus, but as they are sick-looking it is usually this combined with other clinical signs which prompts surgical referral, rather than the false reassurance of non-green vomitus.
After the neonatal period, volvulus and malrotation can still occur but bilious vomiting can also happen as part of a viral gastroenteritis. Differentiation can be made clinically; children with volvulus/malrotation are unwell and often in shock, with a taut, tender abdomen, and high pitched or absent bowel sounds.
What do parents mean?
Parents generally mean “vomit which came out with any sort of force, rather than just dribbling from the baby’s mouth.” Given that human beings have a vomiting reflex which invokes downward contraction of the diaphragm with contraction of the musculature of the abdominal wall and stomach itself, it’s not surprising that vomiting comes out with force at times. In fact, the very definition of the word vomit contains forceful adjectives. Parents often worry if children vomit in their sleep that they will choke on it; the vomiting reflex exists to prevent this from happening.
What do we mean?
Projectile vomiting is unusually forceful and the vomitus travels a significant distance. Projectile vomiting of significance usually occurs without retching but there’s not actually a consensus definition of how projectile vomitus should be (or how far it should go) before it is considered pathologically projectile. This is where test feeds in ED come in – there are other signs which might be elicited in a baby with a history of vomiting, but vomitus reaching the end of the cot or more than the length of the child’s body is certainly unusual!
What does projectile vomiting mean?
Projectile vomiting can be a sign of congenital pyloric stenosis, a condition in which hypertrophy and hyperplasia of the pyloric muscle causes a gastric outflow obstruction. Vomiting is not bile stained (but may be yellow as milk curdles in the stomach), because bile cannot pass back into the stomach, just as no feed can pass out. Consequently these babies are hungry – starving – and gulp their feeds, only to vomit it back with plenty of force.
Presentation occurs usually in weeks 4-8 of life and there’s a recognised predominance in first-born male babies. In the early stages the baby may not appear unwell; just hungry and vomiting, often infrequently at first. As the condition progresses, vomiting becomes more predictable (after every meal) and parents often blame the milk and try alternative formula. As time passes the baby can become significantly dehydrated and malnourished, and the neonate with established pyloric stenosis will have a characteristic hypochloraemic hypokalaemic metabolic alkalosis from persistent vomiting of gastric HCl (while potassium is lost through exchange in the kidney as the body attempts to preserve hydrogen ions and correct the alkalosis).
As Casey points out, test feeding in the ED is one of our best diagnostic tools in babies who have not yet become critically unwell. Before the vomit, peristalsis may be visible and the textbook description is of a palpable olive-shaped mass in the right upper quadrant or epigastrium. The video below shows peristaltic waves; a more specific clinical sign than reported projectile vomiting.
There’s a nice clinical case here at Life in the Fast Lane.
And in older children? Well, it’s probably just vomit.
What do parents mean?
Brown vomit, or sometimes vomit with bits in.
What do we mean?
Vomit which looks like the black (or VERY dark brown), granular substance you tip out of your cafetiere in the morning when you’ve had your caffeine fix, you terribly middle class doctor, you! OK, I’m joking (and biased as a tea drinker), but consider the socio-economic balance of our patient population. I have certainly worked in areas where asking patients if the vomit was “avocado” coloured is not helpful; the same is true of coffee grounds.
The best image I could find actually comes from a simulation site, complete with simulated coffee ground vomitus recipe…
What does coffee ground vomiting mean?
Coffee ground vomitus (emesis) represents blood which has been in the upper GI tract (usually proximal to the duodenojejunal junction) for a little while – long enough to have had contact with gastric secretions.
With contact with gastric acid, the haem molecules in blood are oxidised, giving a dark brown/black appearance.
It’s often taken to represent an upper GI bleed but actually there are plenty of alternative causes of apparent coffee ground vomitus – in adults, this paper from 2012 describes including acute MI, urosepsis and small bowel obstruction presenting as “coffee ground vomiting”.
True upper gastrointestinal bleeding is rare in children. When it does occur it usually represents peptic ulcer disease or an alternative diagnosis (in which case the coffee grounds don’t represent altered blood anyway). Remember to consider button battery ingestion (rare but deadly) in children presenting with haematemesis.
And please – don’t use urine dipsticks in vomit to test for the presence of blood; as far as I can find there are no reliable test characteristics for the performance of urine dipsticks in this setting so interpretation of the result is pretty meaningless. If you’ve got a good paper which demonstrates otherwise, please get in touch!
So, now you’ve got your (hi)story straight…
We need to talk about managing simple vomiting in kids who don’t have any of these features. But that’s probably enough for now – next time…
This blog post was inspired by a twitter conversation and I therefore consider it crowd-sourced (including the title!): credit due to @ffolliett, @broomedocs, @nomadicgp, @rachrwlands, @kangaroobeach, @DrJHurley and, of course, @MDaware (#damnitseth)
Natalie May @_nmay
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