Neonatal Hypotension & Shock

Lange’s 5th EditionNeonatology: Management,

Procedures, On-Call Problems, Diseases, and Drugs 2004

Are shock and hypotension the same thing? Why or Why not?

Are shock and hypotension the same thing? Why or Why not?

Shock is decreased end organ perfusion

Shock presents before hypotension

Hypotension represents uncompensated shock

Hypotension is >2SD below normal for age

1000-1250g SBP49-61

1251-1500g SBP 46-61

1501-1750 SBP 46-58

1751-2000 SBP-48-61

For infants <30 weeks gestation mean BP should be at least the gestational age

i.e. 29 week GA=MAP 29

Make sure cuff size correct (2/3 of upper arm)

Cuff too small=BP

Cuff too large=BP

Blood Pressure

*But……. Do you have a BP cuff?

What are the signs of shock in a neonate??

Tachycardia

Poor perfusion

Cold extremities with a normal core temperature

Lethargy

Apnea & Bradycardia

Tachypnea

Metabolic acidosis

Weak pulses

Urine Output What is normal?

Normal ~1-2cc/kg/hour

What can make urine output normal or even high even when an infant is in shock???

Is there a history of Birth Asphyxia?

Birth asphyxia may be associated with hypotension

At delivery was there:

• Maternal bleeding– Abrupto placenta– Placenta previa

• Excessively delayed cord clamping

Name the Types of Shock in Neonates

• A• B• C• D• E

• F• G

Types of Shock in a Neonate

• A. Hypovolemic• B. Septic Shock• C. Cardiogenic

Shock• D. Neurogenic• E. Drug-induced

• F. Endocrine • G. Extreme

prematurity

• 3 kg infant presents from outside with extreme pallor, bleeding from umbilical cord and is cold with a HR of 200

• What type of shock• Work-up??• Treatment??

Hypovolemic• Antepartum blood loss (often

associated w/asphyxia)– Abruptio placentae– Placenta previa– Twin-twin transfusion– Fetomaternal hemorrhage

• Postpartum blood loss– Coagulation disorders– Vitamin K deficiency– Iatrogenic causes (loss of catheter– Birth trauma (liver injury, adrenal

hemorrhage, ICH, intraperitoneal hemorrhage

• 1 week old 4 kg infant born to a mother with diabetes. Difficulty with IV therefore UVC placed

• Doing better til this morning when noted to have a systolic BP of 40, HR of 170, temperature of 34°C

• Type of shock• Work-up• Treatment

Septic Shock• Endotoxemia with release of vasodilator

substances• Gram-negative often cause but can

occur with gram-positive

• Infant required bag-mask ventilation at birth presents to nursery noted to be cyanotic, in respiratory distress, cold, clammy without breath sounds of the right

• Type of shock• Work-up• Treatment

Cardiogenic Shock• 1. Birth asphyxia• 2. Metabolic problems (eg

hypoglycemia, hyponatremia, hypocalcemia, acidemia) can decrease cardiac output

• 3. Congenital heart disease (such as hypoplastic left heart or aortic stenosis)

• 4. Arrythmias• 5. Any obstruction of venous return

(tension pneumothorax)

• Term baby with Apgars of 3 at 3 minutes and 5 at5 minutes noted to have poor perfusion on arrival to nursery

• Type of shock• Work-up• Treatment

Neurogenic Shock• Birth asphyxia• Intracranial

hemorrhage

• 2.5 kg infant with status epilepticus and has been loaded with 20mg/kg of phentobarbital initially then given an additional 5mg/kg q 5 minutes X5 for persistent seizures because no other drugs available to control seizures. After 5th dose noted to be very poorly perfused

• Type of shock• Work-up• Treatment

Drug-Induced • Sedatives• Magnesium• Digitalis• Barbituates especially if high dose

• Term infant with ambiguous genitalia present at 3 weeks of age with hypotension

• Type of shock• Work-up (initial)• Treatment

Endocrine Disorders

• Complete 21-hydroxylase deficiency

• Adrenal hemorrhage• (What electrolyte abnormalities do

you expect in adrenogenital syndrome??– A. Low sodium, high potassium– B. Hi sodium, high potassium– C. Low sodium, low potassium

• 27 week infant noted to have a mean arterial blood pressure of 24 on the new automatic BP machine

• Type of shock• Work-up• Treatment

Extreme Prematurity

• Hypotension is very common– 40% in 27-29 weeks– 60-100% in 24-26 weeks– Most likely due to adrenocortical

insufficiency, poor vascular tone, immature catecholamine responses

– Hypotension in ELBW infants is associated w/IVH and needs to be corrected

Work UP

• Look for signs of blood loss, sepsis and clinical signs of shock

• Complete Blood Count– Decreased hematocrit can occur with

bleeding however remember in acute blood loss maybe normal

– Increased or decreased WBC or increase in immature cells may point to sepsis

Work-up continued

• Coagulation studies (if disseminated intravascular coagulation suspected)

• Serum glucose, electrolytes, and calcium levels

• Cultures, CRP• Kleihauer-Betke to rule out fetomaternal

transfusion is suspected• Arterial blood gases to look for hypoxia

and acidosis

Other studies

• CXR • Ultra-sound head• ECG/EKG

Treatment-Determine cause if possible to guide

treatment• 1. Volume expansion• 2. Blood replacement• 3. Empiric antibiotics• 4. Inotropes• 5. Steroids• 6. Blood• 7. Chest aspiration

a. Hypovolemicb. Septicc. Cardiogenicd. Neurogenice. Drug-inducedf. Endocrineg. ELBW

Match the treatments with the causes