You are here: Home / IBCC / Right Ventricular failure due to pulmonary hypertension Show
CONTENTS
approach to decompensated RV failure âś…correct any precipitating factors (link)
The right ventricle is truly the forgotten ventricle. Most textbooks on critical care cardiology are written almost entirely about left ventricular failure. Likewise, nearly all evidence surrounding heart failure is with regards to the left ventricle. There is nearly no high-quality evidence regarding the management of right ventricular failure in the ICU. In the absence of definitive evidence, there are an infinite number of reasonable ways to treat RV failure in the ICU (e.g., using echocardiography versus using a Swan-Ganz catheter). Presenting every reasonable approach would be confusing and lengthy. Consequently, this chapter focuses on a relatively simple and noninvasive strategy towards RV failure. Of course, the general principles should remain applicable, regardless of your preferred approach. Right ventricular failure in the context of pulmonary hypertension is extremely common, occurring in perhaps about a third of patients with ARDS or septic shock. Our most important task in the ICU is identifying all patients with RV failure and providing them with RV-friendly resuscitation. Simple interventions can go a long way in these patients, if we can merely understand their precarious physiology.
relationship between RV failure & pulmonary hypertension
definition of RV failure in the context of pulmonary hypertension
vicious spirals of RV failure
RV myocardial perfusionRV systolic perfusion pressure = (Systolic Bp) – (Pulmonary Artery Systolic Pressure)
RV failure patients can fall off the Starling curve
occult systemic hypoperfusionSystemic Perfusion Pressure = (MAP – CVP)
Causes of pulmonary hypertension can be classified into roughly three buckets: causes of chronic pulmonary hypertension, severe diseases which can cause acute pulmonary hypertension by themselves, and precipitating factors which can make any situation worse. There is some overlap between these buckets. Patients with RV failure often have a combination of numerous factors. Identifying and treating all causative factors is critical. chronic pulmonary hypertension (WHO classification) (32740380, 32115291)
acute pulmonary hypertension
common exacerbating factors
clinical history is variable
clinical features of RV failure, in rough order of increasing severity:
laboratory findings may include:
RV failure on CT scan
echocardiography – see the next section.
Echocardiography can provide a wealth of information about cardiac structure and hemodynamics. This has largely replaced the Swan-Ganz catheter, due to its ability to be performed safely and immediately, at any location. RV dilation
RV septal flattening (“D” sign)
TAPSE (tricuspid annular plane systolic excursion)
central venous pressure (CVP)
PA systolic pressure (PASP)PASP = CVP + 4(max TR jet in m/s)2
signs of chronic pulmonary hypertension
bedside echo bubble study to evaluate severe hypoxemia
Pulmonary artery catheterization (a.k.a. Swan-Ganz catheterization) is one approach to evaluate and monitor right ventricular function. This technique is deemphasized in this chapter for the following reasons:
Any factors promoting pulmonary hypertension should be treated if possible, these will often include:
(More on triggers of decompensation above.)
Any pulmonary dysfunction will increase the pulmonary vascular resistance, thereby increasing the afterload on the right ventricle and worsening RV failure. (#1) liberal oxygen
(#2) optimize lung function
(#3a) if not intubated: avoid intubation
(#3b) if intubated: optimize ventilator settings
optimizing volume status in PH
central venous pressure (CVP) as a fluid target
“squeeze and diurese” strategy
why maintaining an adequate MAP is important:
optimal target MAP?
choice of agent
inhaled pulmonary vasodilators offer numerous benefits:
indications & contraindications
For further discussion see the chapter on inhaled pulmonary vasodilators.
This might be the least desirable medical therapy. Nonetheless, inotropy may be required for patients with inadequate systemic perfusion, despite the above interventions. benefits, risks, & indications:
two options to add inotropy
sildenafil
intravenous pulmonary vasodilators
ECMO
Intubation is fraught with peril for the patient with substantial RV failure. Patients may respond poorly to hypoxemia, hypercapnia, positive pressure, and sedation. When possible, patients and families should be informed regarding these risks and participate in informed consent. However, in the context of critical illness, this is often not possible. There are a variety of different ways to approach this. The ideal way is arguably a hemodynamically neutral intubation, but this may be difficult to achieve on an emergent basis in many units. A more accessible strategy is roughly as follows:
Follow us on iTunes
To keep this page small and fast, questions & discussion about this post can be found on another page here.
Guide to emoji hyperlinksGoing further
References
What is the treatment for right heart failure?Treating right-sided heart failure usually involves using one or more medications, lifestyle measures, and possibly implanted devices that support the heart's ability to pump. Treating left-sided heart failure is also important.
Can pulmonary hypertension cause rightPotential complications of pulmonary hypertension include: Right-sided heart enlargement and heart failure (cor pulmonale). In cor pulmonale, the heart's right lower chamber (ventricle) becomes enlarged. It has to pump harder than usual to move blood through narrowed or blocked pulmonary arteries.
What is the best treatment for pulmonary hypertension?There's no cure for pulmonary hypertension, but treatment is available to help improve signs and symptoms and slow the progress of the disease.. High-dose calcium channel blockers. ... . Blood thinners (anticoagulants). ... . Digoxin (Lanoxin). ... . Water pills (diuretics). ... . Oxygen therapy.. What is a treatment goal in cardiac induced pulmonary hypertension?Current goals include achieving modified New York Heart Association functional class I or II, 6-min walk distance >380 m, normalization of right ventricular size and function on echocardiograph, a decreasing or normalization of B-type natriuretic peptide (BNP), and hemodynamics with right atrial pressure <8 mm Hg and ...
|