Are stress dose steroids helpful in patients with low cardiac output state after pediatric cardiac surgery?

Stress Dose Steroids for Low Cardiac Output Syndrome After Pediatric Cardiac Surgery

Direct Answer

Yes, there is trial evidence demonstrating that stress dose steroids (specifically hydrocortisone) are helpful for low cardiac output syndrome after pediatric cardiac surgery, with the strongest evidence showing reduced prevalence of LCOS and improved hemodynamic parameters in neonates.

Highest Quality Evidence

The most recent and highest quality study is a double-blind randomized controlled trial (2015) that demonstrated prophylactic postoperative hydrocortisone infusion significantly reduced the prevalence of low cardiac output syndrome in neonates after cardiopulmonary bypass 1. In this trial:

• 26% of hydrocortisone-treated patients developed LCOS versus 57% in the placebo group (p = 0.049) 1
• Hydrocortisone patients achieved more negative fluid balance at 48 hours (-114 vs -64 mL/kg; p = 0.01) and greater urine output (2.7 vs 1.2 mL/kg/hr; p = 0.03) 1
• Patients weaned off catecholamines and vasopressin sooner, with significant difference in inotrope-free subjects after 48 hours (p = 0.033) 1
• No hydrocortisone subjects required rescue steroids compared to 24% of placebo subjects (p = 0.02) 1

Dosing Protocol from the Trial

The effective regimen used:

• Initial bolus: 50 mg/m² hydrocortisone after cardiopulmonary bypass separation 1
• Continuous infusion: 50 mg/m²/day tapered over 5 days 1

Supporting Evidence from Earlier Studies

A 2005 retrospective study showed that neonates with resistant LCOS unresponsive to high-dose inotropes responded to hydrocortisone with 2:

• Mean blood pressure increased from 44.0±3.0 to 55.4±2.3 mm Hg (p=0.01) within 3 hours 2
• Systolic blood pressure increased from 64.2±4.7 to 78.3±3.4 mm Hg (p=0.04) 2
• Heart rate decreased from 168.3±4.6 to 148.3±5.6 beats/min (p=0.004) after 24 hours 2
• Epinephrine infusions reduced from 0.16 to 0.06 μg/kg/min (p=0.008) within 24 hours 2
• 83.3% survival rate 2

Important Nuance: Cortisol Levels Don't Predict Response

A critical finding is that baseline cortisol levels do not predict which patients will benefit from hydrocortisone. A 2012 study demonstrated that hemodynamic improvements after hydrocortisone were similar in patients with low baseline cortisol (<100 nmol/L) versus normal cortisol levels (≥100 nmol/L) 3. This means you should not wait for cortisol testing results before initiating therapy in severe LCOS 3.

Guideline Recommendations

The Surviving Sepsis Campaign guidelines (2013) recommend:

• Timely hydrocortisone therapy at stress doses (50 mg/m²/24h) for children with fluid-refractory, catecholamine-resistant shock and suspected or proven absolute adrenal insufficiency (Grade 1A) 4
• Infusions up to 50 mg/kg/day may be required to reverse shock in the short term 4
• Approximately 25% of children with septic shock have absolute adrenal insufficiency 4

The 2010 Pediatric Advanced Life Support guidelines state:

• Stress-dose corticosteroids may be considered in children with septic shock unresponsive to fluids and requiring vasoactive support 4

Contradictory Evidence and Limitations

A 2020 meta-analysis of 17 studies (848 patients) found that perioperative corticosteroids 5:

• Did not significantly reduce all-cause in-hospital mortality (RR = 0.59,95% CI = 0.28-1.25, p = 0.55) 5
• Did reduce vasoactive inotrope score at postoperative day 1 (MD = -2.04, p = 0.04) 5
• Increased blood glucose at postoperative day 1 (MD = 1.38, p = 0.0001) and insulin therapy requirements (RR = 2.69, p = 0.004) 5
• Showed no significant difference in ICU length of stay, duration of mechanical ventilation, or acute kidney injury 5

However, this meta-analysis included heterogeneous studies with varying protocols and patient populations, making it less definitive than the focused 2015 RCT for neonatal LCOS specifically 5.

Clinical Practice Patterns

An international survey (2017) revealed 6:

• 94% of physicians sometimes or always administer corticosteroids for severe LCOS (two or more vasoactive agents with persistent hypotension) 6
• Only 11% prescribe corticosteroids for mild LCOS 6
• Hydrocortisone is the most commonly used agent (88%) 6
• Considerable practice variability exists regarding dosing and cortisol testing 6
• 75% of respondents would randomize patients with severe LCOS into a corticosteroid efficacy trial 6

Practical Algorithm for Use

Consider hydrocortisone when:

1. Patient has severe LCOS requiring ≥2 vasoactive agents with persistent hypotension or poor perfusion 6
2. Patient is unresponsive to fluid resuscitation and escalating inotropic support 2
3. Particularly in neonates within the first 5 days after cardiopulmonary bypass 1

Do not delay treatment for:

• Cortisol level results (levels don't predict response) 3
• ACTH stimulation testing 3

Monitor for:

• Hyperglycemia requiring insulin therapy (occurs in approximately 2.69-fold higher rate) 5
• Blood glucose should be checked at postoperative day 1 and managed accordingly 5

Key Caveat

The strongest mortality and morbidity benefit is demonstrated specifically in neonates with prophylactic use after cardiopulmonary bypass, not necessarily as rescue therapy in all pediatric age groups 1. The evidence for rescue therapy in older children with established severe LCOS is less robust, though hemodynamic improvements are documented 2, 3.