Tetralogy of Fallot (TOF) is a congenital heart defect with four parts: a ventricular septal defect, narrowing of the right ventricular outflow tract and pulmonary valve, an aorta that sits over both ventricles, and a thickened right ventricle. Oxygen-poor blood crosses from the right side to the left and goes out to the body, so the baby is cyanotic, especially during “tet spells.” The nursing diagnoses used most often are Impaired Gas Exchange, Inadequate Protein-Energy Nutritional Intake, Risk for Infection, and Anxiety in the parents. Nursing care centers on recognizing and treating tet spells, keeping the infant calm and well hydrated, supporting feeding and growth until surgical repair, and teaching the family.
At a glance
- What it is
- The most common cyanotic congenital heart defect. Four defects together: ventricular septal defect (VSD), right ventricular outflow tract (pulmonary) stenosis, overriding aorta, and right ventricular hypertrophy. Most children have complete surgical repair in the first year of life.
- Common causes and links
- Usually no single cause is found. It is linked with chromosome and genetic conditions such as 22q11.2 deletion syndrome and Down syndrome, and with maternal diabetes, alcohol use, and some medicines in pregnancy.
- Key signs
- Cyanosis that worsens with crying, feeding, or stooling; a harsh systolic murmur at the left upper sternal border; tiring and sweating with feeds; slow weight gain; clubbing after months of cyanosis; and squatting in toddlers whose defect has not been repaired.
- Nursing focus
- Spotting and treating tet spells, pulse oximetry against the target the cardiology team sets, hydration, calm care, feeding support and daily weights, no air in IV lines, infection prevention, and family teaching before and after surgery.
- Act now
- A tet spell that does not settle quickly with calming and knee-chest positioning, limpness, loss of consciousness, a seizure, or oxygen saturation falling well below the infant’s usual range needs the provider or rapid response team right away.
Why tetralogy of Fallot causes cyanosis
In TOF, the wall between the ventricles has a large hole (the VSD), and the path out of the right ventricle to the lungs is narrowed. Because blood takes the easiest path, some oxygen-poor blood from the right ventricle crosses the VSD and leaves through the aorta, which sits over the hole. This right-to-left shunt sends blue blood to the body. The right ventricle thickens because it pumps against the narrowed outflow tract.
How blue the child is depends mainly on how tight the outflow obstruction is. With mild narrowing, more blood reaches the lungs and the infant may look pink at rest (a “pink tet”). With severe narrowing, the newborn may depend on the ductus arteriosus for lung blood flow and need a prostaglandin infusion to keep it open until a procedure can be done.
Over time, the body responds to low oxygen by making more red blood cells (polycythemia). This thickens the blood. Dehydration makes it thicker still, which raises the risk of clots and stroke. Long-standing cyanosis also causes clubbing of the fingers and toes.
What happens in a tet spell?
A hypercyanotic or “tet” spell is a sudden drop in blood flow to the lungs. Crying, feeding, stooling, pain, fever, or dehydration can set it off. The outflow tract narrows further, or the resistance in the body’s vessels falls, so even more blue blood shunts to the body. The infant becomes deeply cyanotic, breathes fast and deep, and is irritable, then may become limp. The murmur gets softer or disappears, because less blood is flowing across the narrowed outflow tract. Without treatment, a spell can lead to seizures, stroke, or death.
Knee-chest positioning, and squatting in an older child, raises resistance in the body’s vessels, which pushes more blood through the lungs. That is why it is the first action in a spell.
How is it treated?
| Treatment | What it does |
|---|---|
| Complete repair (open-heart surgery) | Patch closure of the VSD and relief of the outflow obstruction, sometimes with a patch across the pulmonary valve. Timing is set by the surgical team, most often within the first year of life. |
| Palliative procedure | For a very small or unstable infant, a shunt (such as a modified Blalock-Thomas-Taussig shunt) or a stent in the ductus or outflow tract adds lung blood flow until complete repair. |
| Medicines before repair | Prostaglandin infusion in newborns who depend on the ductus. A beta blocker such as propranolol may be ordered to reduce spells while the infant waits for surgery. |
| Lifelong follow-up | After repair, many people develop a leaky pulmonary valve, rhythm problems, or a stretched right ventricle, and may need a pulmonary valve replacement later. Follow-up with a congenital heart specialist continues into adulthood. |
Nursing assessment
Subjective data
- From the parents: when the baby turns blue, how long it lasts, and what brings it on (crying, feeding, stooling, waking)
- Episodes of fast, deep breathing, limpness, or unusual sleepiness after crying
- How long a feeding takes, how much the baby takes, and whether the baby sweats, stops to rest, or falls asleep during feeds
- Number of wet diapers, vomiting, diarrhea, or fever, since dehydration can trigger spells
- Medicines given at home and missed doses
- In a toddler: squatting after play, tiring quickly, and shortness of breath with activity
- Family history, prenatal history, and any known genetic condition
- How the parents are coping and what they understand about the plan for surgery
Objective data
- Color of lips, tongue, nail beds, and mucous membranes at rest and with crying or feeding
- Oxygen saturation by pulse oximetry, compared with the infant’s usual range and the target the cardiology team sets
- Heart rate, respiratory rate and effort, temperature, and blood pressure
- Heart sounds: a harsh systolic ejection murmur at the left upper sternal border; note if it becomes softer during a spell
- Clubbing, capillary refill, and peripheral pulses
- Weight, length, and head circumference plotted on a growth chart; daily weight on the same scale
- Intake and output, diaper count, fontanelle, and mucous membranes for hydration
- Lab results as ordered: hemoglobin and hematocrit (often high from chronic cyanosis), iron studies, electrolytes, and blood gases during a severe spell
- Diagnostics as ordered: echocardiogram (confirms the diagnosis), ECG, chest X-ray (may show a “boot-shaped” heart), and cardiac MRI or catheterization before surgery
Nursing diagnoses used with tetralogy of Fallot
- Impaired Gas Exchange — oxygen-poor blood shunting to the body, made worse during tet spells
- Inadequate Protein-Energy Nutritional Intake — tiring and cyanosis during feeds and high calorie needs, leading to slow growth
- Risk for Infection — risk of infective endocarditis with an unrepaired cyanotic defect, plus upcoming surgery and lines
- Anxiety (parents) — a frightening diagnosis, spells at home, and upcoming open-heart surgery
- Decreased Activity Tolerance — tiring with feeding, crying, and play
- Risk for Ineffective Cerebral Tissue Perfusion — thick blood from polycythemia, dehydration, and air or clots crossing the shunt to the brain
- Risk for Decreased Cardiac Output — after surgical repair, from rhythm problems and right ventricular strain
- Caregiver Role Strain — feeding demands, frequent appointments, and caring for a child with a heart condition
Worked care plans
Four plans in the same ADPIE shape. The scenario is a 4-month-old girl with tetralogy of Fallot found after birth when a murmur and a low pulse oximetry screen led to an echocardiogram. She is waiting for complete repair. Yesterday at bath time she cried hard, turned very blue, and breathed fast and deep; it eased when her mother held her knees up to her chest. A second spell this morning brought her to the hospital. Now she is calm in her mother’s arms with mild cyanosis of the lips. Oxygen saturation is 82% to 86% on room air at rest; the cardiology team has set her target range and asks to be called for readings below it. Heart rate is 150, respiratory rate 50, and temperature 37.1°C (98.8°F). She has a harsh systolic murmur at the left upper sternal border. Her weight is 5.4 kg; birth weight was 3.3 kg, and her weight gain has slowed so that she has dropped below her growth curve. Feeds take 40 minutes and she sweats and falls asleep after about half a bottle. She has had fewer wet diapers since yesterday. Hemoglobin is 15.8 g/dL, higher than expected for her age. Genetic testing done after birth was normal. The cardiology team moves her surgery date up and orders oral propranolol, IV fluids, and a dietitian consult.
1. Impaired Gas Exchange
Problem-focusedSubjective: Mother: “When she screamed in the bath she went dark blue, almost purple, and breathed so fast. I didn’t know what to do.”
Objective: Mild cyanosis of the lips at rest. Oxygen saturation 82% to 86% on room air at rest. Two hypercyanotic spells in 24 hours, triggered by crying. Harsh systolic murmur at the left upper sternal border. Hemoglobin 15.8 g/dL.
Impaired Gas Exchange related to right-to-left shunting of blood across the ventricular septal defect and reduced blood flow to the lungs, as evidenced by cyanosis, oxygen saturation of 82% to 86% on room air, and hypercyanotic spells with crying.
- Infant keeps oxygen saturation within the target range the cardiology team sets
- Any tet spell is recognized at once and treated, and resolves without loss of consciousness
- Parents show the knee-chest position and describe when to call for help before discharge
- Keep her on continuous pulse oximetry and cardiac monitoring as ordered, and compare readings with her target range
- Cluster care, comfort her quickly when she cries, and have her mother hold her for procedures when possible
- At the first sign of a spell, calm her and place her in the knee-chest position (held against the shoulder with knees tucked to the chest), give oxygen as ordered, and call for help
- If the spell does not settle, give the medicines and fluids the provider orders for a spell and stay with her
- Give IV fluids as ordered and keep her well hydrated, because dehydration thickens the blood and can trigger spells
- Give propranolol as ordered and check heart rate and blood glucose as your facility directs, since beta blockers can slow the heart and hide low blood sugar in infants
- Remove all air from IV tubing and syringes, and use air filters if your facility requires them, because air can cross the shunt to the brain
Over 48 hours her oxygen saturation stayed within her target range. She had one brief spell during a blood draw that settled within minutes in the knee-chest position with oxygen. Her mother showed the position correctly. Goal met; continue monitoring until surgery.
2. Inadequate Protein-Energy Nutritional Intake
Problem-focusedSubjective: Mother: “Every bottle takes forever. She gets sweaty and falls asleep, and then she’s hungry again an hour later.”
Objective: Feeds take 40 minutes; she finishes about half a bottle. Sweating and lip cyanosis during feeds. Weight 5.4 kg, below her growth curve. Fewer wet diapers since yesterday.
Inadequate Protein-Energy Nutritional Intake related to fatigue and low oxygen during feeding and increased calorie needs, as evidenced by taking half of each feeding, sweating and cyanosis with feeds, and weight gain below her growth curve.
- Infant takes the daily volume and calories the dietitian and provider set
- Infant gains weight at the rate the team sets, checked by daily weights
- Parents describe the feeding plan and the signs of tiring
- Weigh her daily on the same scale, at the same time, without clothes, and record intake, output, and diaper count
- Offer smaller, more frequent feedings and feed when she first shows hunger cues, before she cries hard
- Limit each feeding to the length of time the team sets, often around 30 minutes, so she does not burn more calories than she takes in
- Hold her semi-upright, use a soft nipple as advised, and let her rest and burp during the feeding
- Give higher-calorie formula or fortified breast milk as the dietitian orders
- Watch for cyanosis, sweating, or fast breathing during feeds; stop, calm her, and tell the provider if it continues
- Give tube feedings as ordered if she cannot take enough by mouth
By day 3 she was taking her full ordered volume of fortified formula in smaller, more frequent feeds of about 25 minutes, wet diapers were back to her usual number, and she had gained weight. Goal partly met; continue feeding plan and weekly weight checks after discharge.
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3. Risk for Infection
Risk diagnosis- Unrepaired cyanotic heart defect, which raises the risk of infective endocarditis
- IV line and blood draws
- Upcoming open-heart surgery with a surgical wound, chest tubes, and invasive lines
- Poor nutrition and slow growth
No “as evidenced by” — she has no fever and her IV site is clean. The plan prevents infection and catches one early.
Risk for Infection related to an unrepaired cyanotic heart defect, invasive lines, planned cardiac surgery, and inadequate nutrition.
- Infant stays free of fever and of signs of infection at the IV site and, after surgery, at the incision
- Parents state why dental care and endocarditis prevention matter for their child
- Infant’s vaccines stay on schedule as the cardiology team advises
- Perform hand hygiene and use aseptic technique for IV care and blood draws, following your facility’s line care bundle
- Check temperature and the IV site at the ordered frequency and report fever, redness, swelling, or drainage
- Report fever, poor feeding, or lethargy promptly; in a child with a heart defect these can be early signs of endocarditis or another serious infection
- Keep sick visitors away and teach the family to avoid crowds and sick contacts during respiratory virus season
- Review her immunization record and ask the team about RSV protection, which is advised for many infants with significant heart disease
- Teach the parents that antibiotics before certain dental procedures are recommended for children with unrepaired cyanotic defects and for a period after repair with prosthetic material, as the cardiologist directs
She stayed afebrile with a clean IV site. Her parents explained that she will need early dental care and may need antibiotics before some dental work, and they had a record of her vaccines and an RSV plan. Goal met; reassess after surgery.
4. Anxiety (parents)
Problem-focusedSubjective: Mother: “I’m scared to bathe her or let her cry. What if it happens at night and I don’t see it? And now the surgery is sooner.”
Objective: Mother tearful, has not slept, asks the same questions several times, and watches the monitor constantly. Father is quiet and stays in the hallway during procedures.
Anxiety related to the infant’s hypercyanotic spells, uncertainty about surgery, and an unfamiliar hospital setting, as evidenced by the mother’s tearfulness, poor sleep, repeated questions, and stated fear of caring for the infant at home.
- Parents state that their anxiety is easing and name at least two sources of support
- Parents show how to recognize and respond to a tet spell
- Parents describe what to expect before and after surgery
- Give the parents time to talk, listen to their fears, and acknowledge that tet spells are frightening
- Explain the defect simply, using a heart diagram, and repeat information in small amounts; use teach-back
- Coach them through the knee-chest position and the home spell plan until they can show it on their own
- Involve them in her care, such as feeding, holding during procedures, and comfort measures
- Arrange a pre-surgery visit or tour and a meeting with the surgical team as available
- Refer to social work, child life, and congenital heart parent support groups
- Offer infant CPR teaching before discharge, as your facility provides
By discharge both parents showed the knee-chest position and described when to call 911. The mother said, “I know what to do now, and I know who to call.” Both completed infant CPR and joined a parent support group. Goal met; continue support through surgery.
Interventions and rationales
Client and family teaching
- Learn the signs of a tet spell: sudden deeper blue color, fast and deep breathing, fussiness, then sleepiness or limpness
- During a spell, stay calm, hold your baby with knees tucked up to the chest, and soothe; an older child may squat on their own, so let them
- Call 911 if the spell does not get better within a few minutes, or your child becomes limp, will not wake, or has a seizure
- Give heart medicines exactly as prescribed; do not stop propranolol suddenly, and ask what to do if a dose is missed or your baby is not feeding
- Prevent dehydration: call your provider for vomiting, diarrhea, fever, or fewer wet diapers than usual
- Feed small amounts often, use the formula or fortifier your dietitian chose, and stop to rest if your baby tires or turns bluer
- Keep well-child visits, vaccines, and weight checks on schedule, and ask about RSV protection
- Start dental care early and tell every dentist about the heart defect; ask your cardiologist whether antibiotics are needed before dental work
- Learn infant CPR before going home
- After repair, keep every cardiology appointment for life, even when your child feels well
NurseStudyPrep.com
You’ve read the care plan. Now answer one.
A priority item in the NCLEX format. On Prep, every option gets a written rationale — including the three that are wrong.
A 5-month-old infant with unrepaired tetralogy of Fallot begins crying during a heel stick. The infant suddenly becomes deeply cyanotic, breathes fast and deep, and is very irritable. Which action should the nurse take first?
Why A. This is a tet spell. The knee-chest position raises resistance in the body’s vessels and pushes more blood to the lungs, and it can be done at once without an order. Counting respirations delays treatment, continuing the painful procedure worsens the spell, and the nurse should call for help without leaving the infant. Morphine may be ordered if positioning and oxygen do not work. Prep also explains why each wrong option looks reasonable.
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Frequently asked questions
What is the priority nursing diagnosis for tetralogy of Fallot?
Impaired Gas Exchange is the priority, because the defect sends oxygen-poor blood to the body and tet spells can quickly become life-threatening. Nutrition, infection prevention, and family support follow once oxygenation is managed.
What are the four defects in tetralogy of Fallot?
A ventricular septal defect, pulmonary (right ventricular outflow tract) stenosis, an overriding aorta, and right ventricular hypertrophy. The outflow narrowing and the VSD together cause the right-to-left shunt; the thick right ventricle is the result of pumping against the narrowing.
Why does the knee-chest position help during a tet spell?
Bending the knees to the chest squeezes the large leg arteries and raises resistance in the body’s circulation. Blood then takes the path to the lungs more easily, so less oxygen-poor blood shunts across the VSD to the body. Toddlers do the same thing on their own by squatting.
Why does the murmur get quieter during a tet spell?
The murmur comes from blood flowing through the narrowed outflow tract to the lungs. During a spell, less blood takes that path, so the murmur softens or disappears. A quieter murmur in a bluer infant is a warning sign, not an improvement.
Is tetralogy of Fallot cyanotic or acyanotic?
Cyanotic. It is the most common cyanotic congenital heart defect. Some infants with only mild outflow narrowing look pink at rest, but they can still become cyanotic during crying or a spell.
When is tetralogy of Fallot repaired, and is it cured?
Most children have complete repair in the first year of life, with timing set by the surgical team. Survival after repair is high, but it is not a cure; many people later need treatment for a leaky pulmonary valve or rhythm problems, so they need cardiology follow-up for life.
References
- Herdman, T. H., Kamitsuru, S., & Lopes, C. T. (Eds.). NANDA International Nursing Diagnoses: Definitions and Classification, 2024–2026. Thieme.
- Diaz-Frias, J., & Guillaume, M. Tetralogy of Fallot. In StatPearls. StatPearls Publishing; updated regularly.
- van der Ven, J. P. G., van den Bosch, E., Bogers, A. J. J. C., & Helbing, W. A. Current outcomes and treatment of tetralogy of Fallot. F1000Research, 2019;8:F1000 Faculty Rev-1530.
- Wilson, W. R., Gewitz, M., Lockhart, P. B., et al. Prevention of viridans group streptococcal infective endocarditis: a scientific statement from the American Heart Association. Circulation, 2021;143(20):e963–e978.
- Stout, K. K., Daniels, C. J., Aboulhosn, J. A., et al. 2018 AHA/ACC guideline for the management of adults with congenital heart disease. Circulation, 2019;139(14):e698–e800.
- Centers for Disease Control and Prevention. About tetralogy of Fallot. Congenital Heart Defects. cdc.gov.
- Hockenberry, M. J., Duffy, E. A., & Gibbs, K. D. Wong’s Nursing Care of Infants and Children (12th ed.). Elsevier.
- Ackley, B. J., Ladwig, G. B., Makic, M. B. F., Martinez-Kratz, M. R., & Zanotti, M. Nursing Diagnosis Handbook: An Evidence-Based Guide to Planning Care (13th ed.). Elsevier, 2023.
Oxygen saturation targets, vital sign and lab reference ranges, tet spell protocols and the medicines and fluids used, propranolol dosing and monitoring, IV air filter use, feeding volumes, calorie concentration and time limits, endocarditis prophylaxis, RSV protection, and surgical timing vary by child, by provider, and by facility. Follow the provider’s written orders and your own institution’s policies. This page supports study and does not replace course instruction or clinical judgment.
