Pediatric CHD Periop Manager

kg

Periop Handoff Summary

Pediatric Cardiac Anesthesia

Patient Weight
--
NPO Deficit (Est. 4-2-1)
--

Risk Profile

Faraoni Risk Score
--
--
Triage Classification
--

Crash Sheet

Epi Bolus (10mcg/kg) --
Atropine (0.02mg/kg) --
Succinylcholine (2mg/kg) --
Rocuronium (1mg/kg) --
Calcium Chloride (20mg/kg) --
PRBC (10ml/kg) --

Notes / Handover Instructions

Faraoni Risk Score Calculator

Based on the 2016 AHA/Faraoni model for predicting in-hospital mortality for pediatric CHD patients undergoing non-cardiac surgery.

Total Risk Score

Select factors above

0

Low Risk

Mortality risk comparable to baseline. Proceed with standard pediatric cardiac precautions.

CHOP Anesthesia Triage

Select all applicable patient criteria to determine the recommended anesthesia team.

Recommendation

Select Criteria Below

Please select all applicable clinical features from the categories below.

1. Congenital Heart Disease
2. Heart Failure / Cardiomyopathy
3. Valvar Disease
4. Pulmonary Hypertension
5. Rhythm Disturbances

Systematic Preoperative Assessment

Based on 2023 AHA Scientific Statement. Ensure all domains are reviewed to define the patient's physiological state.

1. History & Functional Status
2. Physical Exam
3. Testing & Diagnostics
4. Management Plan

Modified Blalock-Taussig (mBT) Shunt

Parallel circulation management. Survival depends on passive flow from high-pressure systemic source to low-pressure pulmonary bed.

Parallel Circulation

Qp is dependent on Systemic BP (Pao). If BP falls, pulmonary flow declines regardless of ventilation.

Qp = (Pao - Ppa) / (Rshunt + PVR)

Diastolic Runoff

Patent shunt = Wide pulse pressure & low diastolic BP.
Danger: A sudden "normalization" (narrowing) of pulse pressure suggests occlusion.

Physiology Primer

1. The Parallel Circulation & Qp:Qs

In shunt physiology, Qp is driven by the pressure gradient between the Aorta (Pao) and PA.
Key Equation: Qp = (Pao - Ppa) / (Rshunt + PVR)
If SVR drops (Induction), Pao drops, and pulmonary flow declines dangerously.
Goal Qp:Qs = 1:1 to 1.5:1 ("The Sweet Spot").

2. Physics of Flow (Poiseuille’s Law)

Resistance is inversely proportional to radius to the 4th power (R ∝ 1/r4).
Implication: Tiny changes in shunt diameter (clot/kink) cause massive flow reduction.
Viscosity: Polycythemia increases viscosity → increases resistance → reduces flow.

3. Coronary Perfusion ("The Double Hit")

Coronary Perfusion Pressure (CPP) = Diastolic BP - VEDP.
Shunt Effect: Runoff lowers Diastolic BP. Volume load raises VEDP.
Result: Extreme risk of ischemia. Narrowing pulse pressure is a danger sign of occlusion (loss of runoff).

Clinical Management

Ventilatory Strategy
Parameter To Increase Qp (Hypoxia) To Decrease Qp (Over-circulation)
FiO2Increase (1.0)Decrease (0.21 or 0.17)
Minute VentHyperventilateHypoventilate
PaCO230-35 mmHg50-60 mmHg
pH> 7.45 (Alkalosis)7.30-7.35 (Acidosis)
Differential Diagnosis: Instability
Feature Shunt Occlusion Over-circulation
SpO2Low (< 60%)High (> 90-95%)
Pulse PressureNarrowing (Diastolic Rise)Widening (Diastolic Drop)
MurmurAbsent / SilentLoud, Continuous
EtCO2Sudden Drop (Dead Space)Rise (Poor washout/Edema)
O2 ResponseMinimal / NoneImproves (Worsens steal)

Pulmonary Hypertension Guide (Maron 2023)

Based on the revised definitions and clinical approach to management.

Revised Hemodynamic Definitions

Mean PAP
> 20 mmHg
(Previously > 25 mmHg)
PVR
> 2.0 WU
(Previously > 3.0 WU)

"Mild PH (mPAP 21-24 mmHg) is pathogenic and associated with increased mortality. Early diagnosis is key."

Clinical Classification (5 Groups)

1. PAH (Pulmonary Arterial Hypertension)
Idiopathic, Heritable, Drug-induced, CTD, HIV, CHD.
2. Left Heart Disease (Most Common)
HFpEF, HFrEF, Valvular disease. (Post-capillary PH: PAWP > 15).
3. Lung Disease / Hypoxia
COPD, ILD, Sleep Apnea, High Altitude.
4. Pulmonary Artery Obstructions
CTEPH (Chronic Thromboembolic PH). Potentially curable.
5. Multifactorial / Unclear
Sickle cell, Sarcoidosis, Metabolic disorders.

PAH Treatment Approach

1
Vasoreactivity Testing (Cath Lab)
Inhaled NO. Positive if mPAP drops ≥ 10 mmHg to ≤ 40 mmHg with stable CO.
If Positive (Reactive):
Treat with Calcium Channel Blockers (Amlodipine, Nifedipine).
If Negative (Non-Reactive):
Assess Risk Profile (WHO-FC, BNP, 6MWD).
  • Low/Int Risk: Oral Combination (ERA + PDE5i). e.g., Ambrisentan + Tadalafil.
  • High Risk: Parenteral Prostacyclin (Epoprostenol/Treprostinil) + ERA + PDE5i.

Drug Dosage Calculator

Calculated based on weight input. Verify all doses before administration.

Medication Standard Dose Calculated Dose
Warning: No weight entered. Doses cannot be calculated.

Tet Spell (Hypercyanotic Episode)

Spasm of RVOT causes R-to-L shunting. Goal: Increase SVR, Decrease PVR.

1
Stop Stimulus & Calm Patient
Pain, agitation, and light anesthesia trigger spells.
2
Knees-to-Chest Position
Mechanically increases SVR by kinking femoral arteries.
3
100% Oxygen
Potent pulmonary vasodilator.
4
Give Phenylephrine ---
Gold Standard. Increases SVR forcefully.
Range: --- - ---
5
Fluid Bolus ---
Increases preload to stent open the RVOT.
6
Esmolol / Beta Blocker ---
Relaxes infundibular spasm (0.5 mg/kg).
Warning: No weight entered. Doses cannot be calculated.

PH Crisis

Acute rise in PVR > SVR causing RV failure and cardiac arrest.

1
FiO2 1.0 (100% Oxygen)
Immediate administration.
2
Hyperventilate
Target pH > 7.45. Alkalosis relaxes pulmonary vessels.
3
Deepen Anesthesia & Paralyze
Eliminate sympathetic surge.
Rocuronium: --- (1 mg/kg)
4
Inhaled Nitric Oxide (iNO)
20-40 ppm. Selective pulmonary vasodilator.
5
Maintain SVR Crucial
SVR must be > PVR to perfuse coronaries.
Norepinephrine: 0.05 - 0.5 mcg/kg/min
Vasopressin: 0.2 - 1.0 milliunits/kg/min
6
Support RV ---
Inotropy for failing RV.
Milrinone: Load 50 mcg/kg (Caution: Hypotension)
Epinephrine: 0.01 - 0.1 mcg/kg/min
Warning: No weight entered. Doses cannot be calculated.

Shunt Occlusion (Acute Thrombosis)

Signs: Refractory Hypoxemia (< 60%), Loss of Murmur, Narrowing Pulse Pressure.

1
CALL FOR HELP & 100% Oxygen
Activate Cardiac Surgery / ECMO immediately. Manual Ventilation.
2
Boost SVR (Phenylephrine) ---
Goal: Force blood through the shunt. Do not fear HTN. Dose: 5-10 mcg/kg.
3
Volume Expansion ---
Hypovolemia exacerbates thrombosis. Keep tank full.
4
Heparin (Early) ---
Prevents propagation. Dose: 50-100 units/kg.
5
Restart PGE1
0.05 - 0.1 mcg/kg/min. Duct may still be responsive.
6
Definitive Intervention
Surgical Exploration (Gold Standard) or ECMO.

Physiologic Manipulation of PVR & SVR

Parameter To Decrease PVR
(Increase Pulmonary Flow)		 To Increase PVR
(Decrease Pulmonary Flow)
FiO2 Increase (Hyperoxia) Decrease (Hypoxia)
PaCO2 Hypocapnia (Hyperventilation) Hypercapnia (Hypoventilation)
pH Alkalosis Acidosis
Lung Vol Normal FRC High PEEP / Atelectasis

Qp:Qs Ratio (Shunt Fraction)

Qp/Qs = (SaO2 - SvO2) / (SpvO2 - SpaO2)

Key Insight: In mixing lesions (Single Ventricle), SaO2 equals SpaO2. Therefore, a saturation of 75-85% typically correlates with a balanced Qp:Qs of 1:1.

Saturations > 90% often indicate Qp:Qs > 1 (Pulmonary Overcirculation).