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Next Lesson - Child Safeguarding
Contents
Abstract
- Sepsis in children can often be missed as the presentation is very similar to that of a normal viral illness.
- Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection (the body’s own response to the infection goes wrong and starts to damage its organs).
- Suspected infection with life-threatening organ dysfunction defines paediatric sepsis. Clinical warning signs guide early recognition; do not wait for a diagnostic score before assessing and treating an unwell child.
- We assess children with sepsis using an A to E approach (Airway, Breathing, Circulation, Disability, Exposure) and manage them using the paediatric SEPSIS 6 guidelines.
Core
Failing to spot paediatric sepsis can lead to the deaths of children, so recognising it early is essential.
The issue with sepsis is that it does not always present clearly and there is no quick test or single clinical sign that reliably identifies it. All of the signs of sepsis are very similar to that of a normal viral illness until the child becomes critically ill.
The definition of sepsis is important so that the common features of severe infections can be identified as early as possible. The presentations and associated symptoms with a severe infection were originally thought to be as a result of inflammation in the body. The first early warning system for identifying sepsis was therefore a list of all the different ways that widespread inflammation could present. The more of these features a child had, the higher the risk of severe infection. This list has since been refined over multiple iterations based upon studies and vast amounts of data collected from those patients that present with severe infections.
Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection (the body’s own response to the infection goes wrong and starts to damage its organs). The harmful response can affect organs beyond the site of infection. The infection itself does not have to spread throughout the body, and a positive blood culture is not required for sepsis.
Therefore, the definition of sepsis is “A life-threatening organ dysfunction caused by a dysregulated host response to infection”.
Adult SOFA (Sequential Organ Failure Assessment) and qSOFA (quick SOFA) scores are scoring tools for adults. They should not be substituted for paediatric assessment. In children, use age-appropriate clinical assessment and local sepsis pathways to recognise deterioration and begin treatment promptly.
The 2005 paediatric consensus used systemic inflammatory response syndrome (SIRS, a set of body-wide signs of inflammation) criteria with infection. The following features are historical inflammatory indicators, not the current definition of paediatric sepsis:
- A temperature, either high or low
- A raised heart rate
- A raised respiratory rate
- A high or low white cell count
The 2024 Phoenix consensus identifies paediatric sepsis in children under 18 years as suspected infection with a Phoenix Sepsis Score of at least 2[5]. The score gives points for potentially life-threatening dysfunction of four body systems: respiratory (breathing), cardiovascular (heart and circulation), coagulation (blood clotting) and neurological (brain and nerves). SIRS with infection alone does not define sepsis. Phoenix is not an early screening tool: clinical concern should prompt assessment and treatment before organ dysfunction is overt. The criteria do not apply to birth hospitalisations (the hospital stay of a newborn baby after birth) or to neonates (babies in the first 28 days of life) below 37 weeks postconceptional age (gestational age plus age since birth). In the UK, NICE (guideline NG254, 2025) uses the same definition of sepsis. However, it grades risk using age-based risk criteria (tables of warning signs for each age group) and suggests considering an early warning score (a score that adds up a child’s vital signs to show how unwell they are), rather than using the Phoenix score[6].
The term severe sepsis is redundant in the current definition because sepsis already requires life-threatening organ dysfunction. Septic shock is sepsis with cardiovascular dysfunction (the heart and blood vessels are not delivering enough blood to the organs); Phoenix identifies this by at least one cardiovascular score point.
A Swiss study (2011 to 2015) looked at children whose blood cultures grew bacteria (blood culture-proven bacterial sepsis) and who also met the SIRS criteria[1]. About one third of the episodes occurred in neonates, one third in previously well children and one third in children with comorbidities (other long-term health conditions). Overall, 7% of the episodes ended in death in hospital within 30 days. Death was more likely in neonates (11%) and in children with comorbidities (7%) than in previously well children (3%).
All of the children in this study had SIRS and bacteria in the bloodstream. Of those without organ dysfunction, 1% died, compared with 17% of those with organ dysfunction. These historical study categories should not be confused with the current Phoenix definition; infection-associated organ dysfunction remains the central concern[1][5].
The bodies of children are very effective at compensating for infection. This means that an ordinary viral infection and sepsis can look similar at first, until the septic child collapses.
Children should be assessed in a specific A to E order. Note this is different to the adult emergency A to E assessment but uses the same principles[2].
The appearance of a child is a good indicator as to how well they are. If the patient looks mottled (patchy, marbled skin), ashen (grey), cyanotic (blue lips or skin) or has a non-blanching rash (a rash that does not fade when pressed) then they should be immediately assessed by a senior and appropriate management started.
The child’s breathing is often a very sensitive indicator as to how well they are doing. The respiratory rate is the number of breaths a child takes in a minute. A fast breathing rate (tachypnoea) is one of the common early findings in children with septic shock, together with a fast heart rate (tachycardia). Assess the child’s need for any additional oxygen based on appearance and oxygen saturations. Assessment of additional sounds of breathing (e.g. wheeze, a whistling sound when breathing out, or stridor, a harsh, high-pitched sound when breathing in) should also be undertaken.
The circulatory system behaves differently in children than it does in adults. Children have the ability to maintain their blood pressure for a relatively long time when they are seriously ill. They do this by speeding up the heart and narrowing their blood vessels. Therefore, a low blood pressure in a young child is a very serious, late sign and requires immediate management. Heart rate, urine output and lactate (a chemical that builds up when the tissues do not get enough oxygen) are used to give an indication of the patient’s circulatory system function. Capillary refill time (how quickly colour returns to the skin after it is pressed) can be used as part of the overall assessment of perfusion, but it is non-specific and can be prolonged by factors such as cold exposure. A normal temperature is not reassuring, as children with serious infection may be normothermic (normal temperature) or hypothermic (low temperature).
The patient’s demeanour can give insight into the severity of illness. A child who is active, talking and crying is less concerning than one who is lying quietly and unresponsive.
The last stage of the assessment is to expose the patient fully, looking for any rashes, wounds or surgical scars, any foreign material or devices.
The risk of a child developing sepsis is based upon the patient’s risk factors and physiology.
Pre-existing risk factors include:
- Younger age, especially under 1 year (the immune system is still developing)
- Impaired immune system (e.g. steroid or chemotherapy treatment; chemotherapy means drugs used to treat cancer)
- Co-existing illness (e.g. cystic fibrosis)
The more risk factors present, the lower the threshold for treating the child for the infection. In other words, start treatment sooner, even when the signs are less clear.
Managing sepsis in paediatric patients is done through the Paediatric Sepsis 6 Pathway.
The first step in every management pathway for the child with sepsis begins with recognising that the patient is severely ill enough to require this pathway. Help should be sought from the most senior doctor available as soon as possible.
The patient should be given high flow oxygen as soon as possible if they are in shock or have an oxygen saturation below 92% in air, considering the use of an adjunct (a simple device, such as an airway tube, that helps to keep the airway open) to help maintain a clear airway if needed. This should be given alongside starting continuous observations, such as pulse oximetry (a probe that measures oxygen saturation) and cardiac monitoring (continuous recording of the heart rate and rhythm). Oxygen can also be given at higher saturations if clinically indicated.
Access should be acquired through an intravenous route, or if proving too difficult, an intraosseous (IO) route (a needle placed into the bone marrow). At this point, bloods should be taken: blood cultures (to find the bacteria causing the infection), a full blood count (the numbers of each type of blood cell), urea and electrolytes and creatinine (kidney function), C-reactive protein (a blood marker of inflammation), liver function tests (how well the liver is working) and a clotting screen (how well the blood clots). Blood cultures should be taken before antibiotics are given. The antibiotics should be broad-spectrum (active against many types of bacteria) and given without delay, within 1 hour of recognising that the child meets any high risk criterion. The choice of antibiotic depends on the child’s age, where the infection was acquired and local guidelines.
Children with high-risk suspected sepsis and a lactate of 2 mmol/litre or more should be given an initial bolus (a rapid dose of fluid into a vein) of 10 ml/kg, according to their weight. NICE recommends a glucose-free crystalloid (a salt solution) with a sodium content of 130 to 154 mmol/litre, such as isotonic saline (0.9% sodium chloride), given over less than 10 minutes up to a maximum of 250 ml. Smaller volumes may be needed in children with heart or kidney disease. Review the child after each bolus. If there is no improvement, give a second bolus. If there is still no improvement, a consultant should attend in person. If the lactate is below 2 mmol/litre, consider giving a bolus.
Initial blood testing in a child with high-risk suspected sepsis should include a venous blood gas with glucose and lactate (a quick test on a blood sample from a vein). Lactate contributes to the assessment of illness severity and perfusion and must be interpreted alongside the clinical findings. Arterial blood sampling may be useful for other clinical indications, but is not required solely to obtain the initial lactate measurement.
Any abnormalities on the blood tests should be addressed at this stage, such as hypoglycaemia (low blood glucose), hyperkalaemia (high blood potassium) or hypocalcaemia (low blood calcium).
Inotropes are drugs that can be given to support the cardiovascular system if the child does not improve after fluid boluses (for example, if heart rate, capillary refill time, urine output and blood pressure do not improve). Inotropes should be prescribed by a senior doctor, with advice from the critical care team.
Look for the source of the infection as part of the assessment. Some sources, such as a collection of pus (an abscess) or a perforated bowel (a hole in the wall of the gut), need drainage or surgery. Involve the relevant surgical team early if this is suitable.
In summary, the steps involved in the paediatric sepsis 6:
- Give high flow oxygen if the child is in shock or has an oxygen saturation below 92% in air
- Obtain access (either IV or IO) and take bloods (including blood cultures, a venous blood gas with glucose and lactate, and a clotting screen)
- Give IV or IO antibiotics
- Consider fluid resuscitation: if the lactate is 2 mmol/litre or more, give a 10 ml/kg bolus without delay and review after each bolus
- Involve senior clinicians/specialists early
- Consider inotropic support early
All of the above should be completed within the first hour of recognising sepsis (when the child is first identified as meeting any high risk criterion)[3][6][7]. If this is achieved, the better the outcome for the child, with the length of stay in paediatric intensive care, general hospital and mortality rate is almost halved. Children’s sepsis boxes can be found on all children’s wards containing everything that is needed to treat the unwell child. A UK audit by the Paediatric Intensive Care Society, published in 2009, found that the fluid and inotrope management recommended by the 2002 American guideline was not followed in 62% of children in septic shock who were accepted for paediatric intensive care[4].
[1] https://www.thelancet.com/journals/lanchi/article/PIIS2352-4642(17)30010-X/fulltext
[2] https://www.nice.org.uk/guidance/ng51/chapter/recommendations (NG51 was replaced in November 2025 by NICE NG254 for under 16s, see reference [6])
[4] https://doi.org/10.1136/adc.2008.153064 (Inwald et al., Archives of Disease in Childhood, 2009)
[5] https://doi.org/10.1001/jama.2024.0179 (Schlapbach et al., JAMA, 2024: the Phoenix criteria)
[6] https://www.nice.org.uk/guidance/ng254 (NICE NG254, suspected sepsis in under 16s, November 2025)
[7] https://sepsistrust.org/wp-content/uploads/2024/08/Sepsis-Acute-Under-5-2024-V1.0.pdf (UK Sepsis Trust acute sepsis screening tool for children under 5, 2024, including the Paediatric Sepsis Six)
[8] https://doi.org/10.1542/peds.112.4.793 (Han et al., Pediatrics, 2003)
Edited by: Dr. Maddie Swannack
Reviewed by: Dr. Thomas Burnell and Dr. Marcus Judge
Quiz
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