Cite this article as:
Miller, T. An approach to the floppy infant, Don't Forget the Bubbles, 2020. Available at: http://doi.org/10.31440/DFTB.25882
You are a junior doctor doing a rotation in neonates. Your registrar asks you to assess a 2-day old baby who was found to be hypotonic on their baby check. They ask you your approach to assessing the “floppy infant”. Luckily, you have a stepwise approach to answer this question ready!
Step 1- Definition and terminology
What does the term floppy mean?
The word floppy can be used to mean:
A decrease in muscle tone (hypotonia)
A decrease in muscle power (weakness)
Ligamentous laxity and an increased range of joint mobility
What does the term hypotonia mean?
It is defined as “resistance to passive movement around the joint”
It’s assessed in two ways by clinicians
Phasic tone: assessed by the response of the muscle to a rapid stretch (tendon reflexes)
Postural tone: measured by the response of the muscle to a sustained low-intensity stretch (maintaining posture against gravity = significant head lag on pull-to-sit, ragdoll posture on ventral suspension, slipping through the hands when the infant is held under their arms).
With that in mind, you go on to start your approach
Step 2 – A focused history
Discuss with mother and review the notes focusing in on specific risk factors that could give you a clue to the diagnosis
Antenatal history – Reduced fetal movements, polyhydramnios, breech presentation
Family history – Muscle disease, stillbirth or consanguinity
Birth History – Labour, delivery, resuscitation, Apgar score and cord gases
History since delivery- Respiratory effort, feeding history, level of alertness, level of spontaneous activity and character of cry
Step 3 – Examination and clinical clues
As always, your examination should start with a top to toe assessment of the baby using an A-E approach. Specific to the floppy baby is your neurological examination.
Some clinical clues that may further help you:-
Poor swallowing ability as indicated by drooling and oropharyngeal pooling of secretions
The cry!! Infants with consistent respiratory weakness have a weak cry
Paradoxical breathing pattern – intercostal muscles paralyzed with intact diaphragm
It is important to determine whether the hypotonia is central (upper motor neuron) or peripheral (lower motor neuron).
*open mouth with tented upper lip, poor seal when sucking, lack of facial expressions, ptosis
TIP- Examine the baby with mum in a familiar environment to increase the likelihood of the baby being alert but not unsettled or crying.
Remember that in the neonatal period, central causes account for two-thirds of all cases, with hypoxic ischaemic encephalopathy being the most common.
Now you have narrowed down the likely lesion type let’s think of some aetiologies. Time to think back to the corticospinal tract that you learned all those years ago in medical school to help you.
Step 4 – Investigations
So what next? Let us decide which investigations we think are appropriate according to our central or peripheral causes.
Management plans will differ from case to case but should include a multi-disciplinary team approach.
Hypotonia can cause a loss of airway control and diminished breathing effort therefore some babies will need:
Resuscitation at birth
Assistance in maintaining airway
Ongoing respiratory support
Regular physiotherapy: stretches aimed at the prevention of contractures, positioning.
Occupational therapy: important to facilitate activities of daily living
Vigorous treatment of respiratory infections, including annual influenza vaccination
Feeding strategies – Nasogastric tube or gastrotomy
Management of gastro-oesophageal reflux.
Evaluation and treatment of cardiac dysfunction
Parental counseling
Later:
Prevention and correction of scoliosis with orthopaedic input
Consideration to the ethical appropriateness of & considerations to the ethical appropriateness of CPR in the event of acute respiratory arrest
Follow up of general development and stimulation of learning.
Please note that with advances in treatment of SMA and potential gene therapy in DMD, early diagnosis is important. Initiation of early treatment is recommended for individuals with infantile-onset (Type 1) and pre-symptomatic SMA.
Selected references
Ahmed MI, Iqbal M, Hussain N. A structured approach to the assessment of a floppy neonate. J Pediatr Neurosci. 2016;11(1):2-6. doi:10.4103/1817-1745.181250
Leyenaar J, Camfield P, Camfield C. A schematic approach to hypotonia in infancy. Paediatr Child Health. 2005;10(7):397-400. doi:10.1093/pch/10.7.397
Author: Taryn Miller“The real baby doc “- junior paeds doc interested in neonates and acute care medicine. Currently, an ex-pat in Melbourne living the Australian dream spending my time swimming, brunching, and beating my partner at chess.
An approach to the floppy infant
Tags: floppy baby, floppy infant, hypotonia
Miller, T. An approach to the floppy infant, Don't Forget the Bubbles, 2020. Available at:
http://doi.org/10.31440/DFTB.25882
You are a junior doctor doing a rotation in neonates. Your registrar asks you to assess a 2-day old baby who was found to be hypotonic on their baby check. They ask you your approach to assessing the “floppy infant”. Luckily, you have a stepwise approach to answer this question ready!
Step 1- Definition and terminology
What does the term floppy mean?
The word floppy can be used to mean:
What does the term hypotonia mean?
It is defined as “resistance to passive movement around the joint”
It’s assessed in two ways by clinicians
With that in mind, you go on to start your approach
Step 2 – A focused history
Discuss with mother and review the notes focusing in on specific risk factors that could give you a clue to the diagnosis
Step 3 – Examination and clinical clues
As always, your examination should start with a top to toe assessment of the baby using an A-E approach. Specific to the floppy baby is your neurological examination.
Some clinical clues that may further help you:-
It is important to determine whether the hypotonia is central (upper motor neuron) or peripheral (lower motor neuron).
*open mouth with tented upper lip, poor seal when sucking, lack of facial expressions, ptosis
TIP- Examine the baby with mum in a familiar environment to increase the likelihood of the baby being alert but not unsettled or crying.
Remember that in the neonatal period, central causes account for two-thirds of all cases, with hypoxic ischaemic encephalopathy being the most common.
Now you have narrowed down the likely lesion type let’s think of some aetiologies. Time to think back to the corticospinal tract that you learned all those years ago in medical school to help you.
Step 4 – Investigations
So what next? Let us decide which investigations we think are appropriate according to our central or peripheral causes.
Central hypotonia
1st line to consider
2nd line to consider
Peripheral hypotonia
1st line to consider
2nd line to consider
Step 5 – Formulating a management plan
Management plans will differ from case to case but should include a multi-disciplinary team approach.
Later:
Please note that with advances in treatment of SMA and potential gene therapy in DMD, early diagnosis is important. Initiation of early treatment is recommended for individuals with infantile-onset (Type 1) and pre-symptomatic SMA.
Selected references
Ahmed MI, Iqbal M, Hussain N. A structured approach to the assessment of a floppy neonate. J Pediatr Neurosci. 2016;11(1):2-6. doi:10.4103/1817-1745.181250
Leyenaar J, Camfield P, Camfield C. A schematic approach to hypotonia in infancy. Paediatr Child Health. 2005;10(7):397-400. doi:10.1093/pch/10.7.397
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