Pericardial Flashcards
What is the pericardium
The pericardium is a sac surrounding the heart.
- Two tissue layers:
- Visceral, a thin tissue-like layer
- Parietal, a more fibrous, rigid layer
- Pericardial cavity
- holds 20 – 50 ml of pericardial fluid.
Pericardial pressure is similar to pleural pressure varying with respiration between –4 mm Hg and +4 mm Hg.
Pericardium function
- Prevents infection
- Lubricates the heart
- Facilitates motion within the sac
- Protects the heart from excessive displacement
- maintains optimum shape of the heart
- Applies a compensatory hydrostatic pressure to the heart
- to compensate for alterations in gravitational force
Acute pericarditis
what is it
what are the causes
Inflammation of the pericardium
Causes:
- infection
- viral
- bacterial
- fungal
- tuberculous
- myocardial infarction
- trauma/cardiotomy
- metastatic disease
- drugs
- mediastinal radiation
- systemic diseases:
- Rheumatoid Artheritis
- Lupus
- Scleroderma
Acute Pericarditis - diagnosis
- Sudden onset of severe chest pain exaggerated by inspiration
- Diffuse ST segment elevation, PR segment depression, T wave inversion
- Pericardial friction rub
Acute Pericarditis - treatment
Treatment:
- Salicylates or NSAIDS
- Analgesics (Indomethacin)
- Corticosteroids
Acute pericarditis in the absence of effusion does not alter cardiac function.
Pericardial Effusion
what is it
causes
diagnosis
- Accumulation of pericardial fluid in the pericardial cavity
- Causes:
- Idiopathic-unknown cause
- Neoplastic
- Diagnosis
- ECHO - the most useful method for clinical detection of effusion – it is very accurate on estimating effusion size
- Signs and symptoms depend on the rate of fluid accumulation
- Acute: with an rapid effusion, the pericardium does not have time to accommodate, so intrapericardial pressures increase significantly and cardiac tamponade results - Even small volumes of fluid (100 – 200 ml) that accumulate rapidly will cause cardiac tamponade
- Gradual: if the effusion develops gradually, the pericardium stretches to accommodate fluid - A large volume of fluid (up to 1000 ml) can accumulate without a significant increase in pressure
Cardiac Tamponade
What is it
- Cardiac tamponade exists when an increase in pericardial pressure impairs diastolic filling of the heart.
- Cardiac filling is related to the diastolic transmural (distending) pressure across each chamber
- Transmural pressure = Pressure within the chamber - extracavity pericardial pressure
- Any increase in pericardial pressure relative to the pressure within the chamber reduces filling
- Medical Emergency
Cardiac Tamponade
Signs and Symptoms
- Increased central venous pressure
- Pulsus paradoxus
- Equalization of cardiac filling pressures
- Hypotension
- Decreased CO, SV
- Decreased voltage on ECG
- Activation of the SNS
- Tachypnea
- JVD
- Muffled heart sounds
Cardiac Tamponade
Treatment
removal of fluid
- Pericardiocentesis
- Subxiphod pericardiostomy
- Thoracic pericardiostomy (open or thoroscopic)
Cardiac Tamponade
Anesthetic Management
- Expand intravascular volume
- Increase myocardial contractility
- Isoproterenol
- Correct metabolic acidosis
- Can do under local, or with Ketamine
Constrictive Pericarditis
What is it
Causes
Fibrous scarring and adhesions of the pericardial cavity that creating a rigid, stiff shell around heart that limits filling of the heart
Causes
- Idiopathic
- Previous cardiac surgery
- Exposure to radiotherapy
- TB
Constrictive Pericarditis sxs
- CVP, RAP, PCWP elevated
- CO decreased
- Fatigue
- Atrial dysrhythmias
- Edema
- Ascites
- Hepatomegaly
- Pulsus paradoxus
- JVD
Constrictive Pericarditis - treatment
Surgical stripping and removal of adherent constricting pericardium (pericardiectomy)
Constrictive Pericarditis - anesthetic management
- Minimize changes to HR, SVR, preload, and contractility
- use: ketamine, etomidate, pancuronium
- Avoid bradycardia
- Maintain intravascular volume to avoid hypotension
- have large bore IV’s, A-line
- Blood transfusions may be necessary to treat blood losses associated with pericardiectomy
