What is the management for a neonate in refractory shock with hypoxemia?

Management of Neonate in Refractory Shock with Hypoxemia

For a neonate in refractory shock not maintaining saturation, immediate implementation of ECMO (Extracorporeal Membrane Oxygenation) is indicated when standard therapies fail to restore adequate tissue perfusion and oxygenation. 1

Initial Assessment and Resuscitation (First 5 Minutes)

• Maintain airway and establish access according to NRP guidelines
• Recognize decreased perfusion, cyanosis, and respiratory distress
• Begin high-flow oxygen (initially 100% oxygen)
• Establish IV/IO access immediately
• Administer fluid boluses of 10 cc/kg isotonic saline or colloid up to 60 cc/kg until perfusion improves
• Begin prostaglandin E1 until ductal-dependent lesion is ruled out
• Correct hypoglycemia and hypocalcemia
• Begin broad-spectrum antibiotics

Hemodynamic Support (First 15 Minutes)

Fluid-Refractory Shock Management:

• Titrate dopamine 5-9 mcg/kg/min 1, 2
• Add dobutamine up to 10 mcg/kg/min 1

Fluid-Refractory Dopamine-Resistant Shock (60 Minutes):

• Titrate epinephrine 0.05 to 0.3 mcg/kg/min 1, 3
• For persistent hypotension, consider norepinephrine while maintaining ScvO2 >70% 1

Pulmonary Hypertension Management

• Hyperoxygenate initially with 100% oxygen 1
• Institute metabolic alkalinization (up to pH 7.50) with NaHCO3 or tromethamine 1
• Consider mild hyperventilation to produce respiratory alkalosis until:
  • 100% O2 saturation is achieved
  • <5% difference in preductal and postductal saturations is obtained 1
• Administer inhaled nitric oxide (iNO) as first-line treatment when available (optimal effect at 20 ppm) 1

Refractory Shock Management

• Rule out and correct unrecognized morbidities: 1

  • Pericardial effusion (pericardiocentesis)
  • Pneumothorax (thoracentesis)
  • Ongoing blood loss (blood replacement/hemostasis)
  • Hypoadrenalism (hydrocortisone)
  • Hypothyroidism (triiodothyronine)
  • Inborn errors of metabolism (glucose and insulin infusion)
  • Cyanotic or obstructive heart disease (prostaglandin E)
  • Critically large patent ductus arteriosus (PDA closure)

• For poor left ventricular function with normal blood pressure:

  • Consider adding nitrosovasodilators or type III phosphodiesterase inhibitors to epinephrine 1
  • Volume load based on clinical examination when using systemic vasodilators 1

• For adrenal insufficiency:

  • Add hydrocortisone if peak cortisol after ACTH <18 μg/dL or basal cortisol <18 μg/dL in volume-loaded patient requiring epinephrine 1

• For VLBW (very low birth weight) babies:

  • Consider pentoxifylline (5-day, 6-hr per day course) 1

ECMO Indication and Implementation

• Implement ECMO when the above measures fail to restore adequate tissue perfusion and oxygenation 1, 4
• Indications for ECMO: 1
  • Refractory shock despite maximal therapy
  • PaO2 <40 mm Hg after maximal therapy
• Current ECMO survival rate for newborn sepsis is 80% 1
• Maintain ECMO flows less than 110 mL/kg to avoid hemolysis 1
• For veno-venous ECMO with persistent hypotension/shock, treat with dopamine/dobutamine or epinephrine 1
• Normalize calcium concentration in red blood cell pump prime (300 mg CaCl2 per unit of packed RBCs) 1

Continuous Monitoring

• Pulse oximetry and arterial blood gas analysis
• Continuous intra-arterial blood pressure
• Temperature, glucose, and calcium concentration
• Fluid balance and urine output
• Central venous pressure/O2 saturation
• Cardiac output and SVC flow
• INR, anion gap, and lactate levels

Therapeutic Endpoints 1

• Capillary refill ≤2 seconds
• Normal pulses with no differential between peripheral and central pulses
• Warm extremities
• Urine output >1 mL/kg/h
• Normal mental status
• Normal blood pressure for age

• 95% arterial oxygen saturation

• <5% difference in preductal and postductal arterial oxygen saturation
• ScvO2 >70%
• Absence of right-to-left shunting, tricuspid regurgitation, or right ventricular failure
• Normal glucose and ionized calcium concentrations
• SVC flow >40 mL/kg/min

Common Pitfalls and Caveats

• Delayed recognition of shock can lead to poor outcomes; monitor for altered mental status, decreased urine output, and elevated lactate 4
• Echocardiographic parameters may not reliably differentiate neonates with septic shock from hemodynamically stable neonates, particularly in gram-negative sepsis 5
• Avoid excessive fluid administration leading to fluid overload; consider diuretics or CRRT for newborns who are 10% fluid overloaded 1
• When using epinephrine, monitor for potential complications including pulmonary edema, cardiac arrhythmias, and tissue necrosis with extravasation 3
• For patients on ECMO with inadequate urine output and 10% fluid overload despite diuretics, CRRT is best performed while on the ECMO circuit 1
• Avoid ECMO flows greater than 110 mL/kg to prevent hemolysis 1