Effusion

Pericardial Effusion - Tamponade

Pericardial effusion. Measurement should be taken in diastole. Tamponade is a diastolic problem, with restrictive filling. Here, the effusion seems circumferential. Not surprisingly, in a newborns that is lying on his back, the effusion collects posteriorly along the posterior wall of the LV. The fluid can be seen in parasternal short and long axis view in this particular case.

Evaluation of restricted filling - PW of RV and LV inflow. 

• Increased tricuspid valve inflow variability on spectral PW-Doppler (normal <40%)

• Increased mitral inflow variability on spectral PW-Doppler (normal <25%)

A good practice is to compress time in order to observe variation in inflow Doppler velocities. This may be altered in individuals that are not spontaneously breathing.

Ref: https://pedecho.org/library/chd/pericardial-tamponade

Measurements should be done at the end of diastole. Here, as outlined by the ECG tracing, just before the P-wave.

Ultrasound signs of Tamponade

Right atrial collapse during ventricular contraction / systole. 

Swinging Heart (M-mode echocardiography): The heart appears to swing back and forth within the pericardial sac during systole and diastole due to the restricted movement caused by the pericardial effusion.

Respiratory flow variation across the atrio-ventricular valves (mitral or tricuspid). Doppler Surrogate of Pulsus Paradoxus.

Right ventricular collapse during ventricular relaxation (diastole) - tamponade is a diastolic and filling condition. This could be appreciated by M-Mode.

Inferior vena cava distended with minimal respiratory variability

More Information Here and Here.

Long axis subcostal / subxyphyoid view outlining circumferential pericardial effusion with collapse of the right atrium.

Subcostal/subxyphoid short axis view outlining circumferential effusion. The IVC is seen distended and without variation in caliber. This outlines some degree of tamponade physiology.

Apical view outlining the RV and RA collabse. RA collabse during systole and RV collapse during diastole. Large effusion not obliterating during diastole.

Parasternal views (long and short axis). One may appreciate the RV collapse during diastole, as well as the circumferential pericardial fluid. 

Emergency Pericardiocentesis Procedure

Multi-Disciplinary Pediatric Point of care Ultrasound Bootcamp Simulation Scenario 

The crashing neonate

Case shared by Dr Brahim Bensouda from Hôpital Maisonneuve Rosemont 

A newborn presented initially with significant retractions without bradycardia. Dr Bensouda, TnECHO specialist and Neonatologist member of the TnECHO Quebec Collaborative, had done the workshop on pericardiocentesis and had trained through simulation on how to perform this technique at the bedside. A TnECHO was obtained and the images are shared below.

The views above are in the subcostal area showing a large pericardial effusion. There is altered filling and contractility. The heart is moving in the pericardial pocket during contraction. The liquid is anechoic (black appearance). 

Milky pink fluid aspirated by emergency pericardiocentesis. After puncture, it is important to remove the needle from the catheter to avoid puncture of the muscle wall upon re-expansion while draining the pericardial fluid. The fluid should be sent for cytology / cell count (especially for lymphocytes), culture, total protein, LDH albumin level, triglycerides and biochemistry (electrolytes and glucose) - to evaluate if presence of total parenteral nutrition (TPN) fluid and intravenous lipid fluid. In this case, upon fluid drainage, one can see that the heart function is back to normal with adequate filling. A catheter is seen in the right atrium, which has been withdrawn.  The fluid analysis was compatible with extravasated TPN/Lipids. 

Bilateral pleural effusions in the subxyphoid view.