ICU and You · Āyubōwan Sri Lanka ආයුබෝවන් · Number 1
Dengue, and a different number to watch
ආයුබෝවන් — āyubōwan is the everyday Sinhala greeting, and it means, more or less, may you live long. For a column that opens on critically ill children, that is either perfect or presumptuous, and I have decided it is perfect.
Sri Lanka is a small country with a long medical tradition, free healthcare at the point of delivery, and a set of diseases that Australian units mostly meet in returning travellers. It also has a way of managing one of them that is more exact than ours, because it has had to be.
A four-year-old has had a high fever for three days. This morning the fever broke. She is quieter, her hands are cool, and everybody is relieved because the fever has gone.
In dengue, that is the moment it starts.
Dengue runs in three phases: febrile, then critical, then recovery. The critical phase — the plasma leak — begins around defervescence, as the temperature comes down, and lasts roughly twenty-four to forty-eight hours. The child who is settling is not necessarily improving. She may be entering the only dangerous part of the illness.
What leaks is plasma, through capillaries that have become permeable. The intravascular volume falls while the total body water does not, which is why the haematocrit rises as the platelets fall. That pair of numbers, moving in opposite directions, is the signal that the leak has started.
A small child compensates for hypovolaemia by constricting and by speeding up. The diastolic pressure rises to meet the systolic, so the pulse pressure narrows long before the systolic falls. Sri Lankan practice treats a pulse pressure of 20 mmHg or less as the threshold of shock, and hypotension as a late and ominous finding rather than the definition.
This is the same physiology our own mind map describes — compensation is efficient, silent, and then abrupt. The difference is that dengue medicine has settled on an instrument for it, and we largely have not.
It is worth putting that beside this fortnight's journal club, where an international consensus could not agree on a blood pressure target for children under twelve. In a Colombo ward the question is answered differently: they do not chase a mean arterial pressure, they watch the gap between systolic and diastolic, the haematocrit, the capillary refill and the urine output, and they act on the first of those to move.
The Australian instinct in a shocked child is a bolus, then reassess, then another. In dengue that instinct is dangerous, and Sri Lankan management is built around restraining it.
The leak is temporary. Everything given during the critical phase is still in the tissues when the capillaries seal, and it then returns to the circulation over the following days. A child who was resuscitated generously is a child who drowns in the recovery phase, and pulmonary oedema after the danger has passed is a recognised way to die of dengue.
So the fluid is calculated rather than titrated: a quota for the critical phase, conventionally maintenance plus a five per cent deficit, given as a tapering regimen and adjusted against haematocrit and urine output rather than against how worried anybody feels. Boluses exist — ten to twenty millilitres per kilogram for established shock — but exceeding the quota is a decision to be justified, not a default. Steroids and immunoglobulin are explicitly not recommended, having been tried and found wanting.
Because we see it in returning travellers, and because the presentation is designed to reassure the unwary. A febrile child back from Colombo or Bali whose fever has just settled is not a child who has turned the corner; she is a child in the first hours of the phase that matters. And because the wider lesson has nothing to do with dengue: when a system has to manage thousands of shocked children with limited intensive care beds, it stops relying on the number that moves last and finds one that moves early. That is a discipline worth borrowing.
Kerosene. If you ask a Sri Lankan paediatrician about poisoning in the one to five year old, they will not say tablets. They will say kerosene, decanted out of the drum into an old soft drink bottle and left where a thirsty toddler can reach it.
The harm is not really the swallowing. It is the aspiration — a low-viscosity hydrocarbon with low surface tension spreads across the alveoli and produces a chemical pneumonitis. Which is why the instinct to make the child vomit is exactly wrong: it converts an ingestion into an inhalation. Most children need oxygen, observation and nothing else, the chest film lags behind the clinical picture, and antibiotics and steroids are not routine.
It is also, like so much of this age group, a housing story before it is a medical one. The bottle is the problem. Australia has its own versions sitting in the shed.
That was something of the Sri Lankan scene. Is there something characteristic of a culture you know, or grew up in?
A disease that is ordinary where you come from and exotic here. A way of managing something that is done differently, and perhaps better. A word that carries a meaning English has no room for. A practice that colleagues here consistently misread.
Tell me about it and we will add your perspective to the cultural narratives on this site — with your name on it, or without, entirely as you prefer. Several of the columns here already exist because somebody wrote in.
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