Cardiac Tamponade - Cardiovascular

Snapshot
A 45-year-old woman presents to the emergency room for chest discomfort and shortness of breath for the past few hours. She has a past medical history of systemic lupus erythematosus. Physical exam reveals hypotension, muffled heart sounds, distended jugular veins, and positive pulsus paradoxus. An echocardiogram (ECG) reveals low voltages and electrical alternans. Imaging shows an enlarged cardiac silhouette on radiography. A team is consulted for an emergent pericardiocentesis.
Introduction
Clinical definition accumulation of fluid in the pericardial sac that restricts ventricular filling Epidemiology risk factors pericarditis malignancy uremia systemic lupus erythematosus malignancy tuberculosis penetrating trauma Etiology pericardial effusion hemorrhage into the pericardial sac iatrogenic Pathoanatomy pericardium the pericardium is an elastic sac that can stretch to accommodate normal cardiac volume expansion however, if stretched beyond normal physiological expansion, the pericardium will stiffen Pathogenesis cardiac tamponade increased pericardial pressure from the fluid accumulation causes compression of the cardiac chambers this results in decreased cardiac output and blood pressure pulsus paradoxus normally, inhalation increases venous return → expands the right ventricle in cardiac tamponade, the stiff pericardium will prevent the free wall from expanding the only area for the right ventricle to expand is the interventricular septum, which will compress the left ventricle compression of the left ventricle → decreased filling of the left heart → decreased blood pressure Associated conditions ruptured ascending aortic dissection ventricular free wall rupture from myocardial infarction Prognosis in acute cases, cardiac tamponade can develop rapidly in chronic cases, cardiac tamponade will develop gradually, as the pericardium can adjust slowly to the increased pressure over time
Presentation
Symptoms chest pain fatigability often unresponsive to fluid resuscitation Physical exam Beck triad muffled heart sounds jugular venous distention hypotension cardiac ↑ heart rate pericardial rub if the patient has an inflammatory pericarditis pulsus paradoxus a decrease in blood pressure > 10 mmHg during inhalation pulmonary shortness of breath lung fields are typically clear extremities cold and clammy peripheral cyanosis
Imaging
Echocardiography indications for diagnosis of cardiac tamponade most accurate test for all patients findings diastolic collapse of the right heart fluid in the pericardial space swinging of the heart within the effusion Radiography indication for all patients views chest findings enlarged cardiac silhouette seen only in subacute cardiac tamponade in acute cases, pericardium will not accommodate build up of > 200 cc of fluid, which is required to appear enlarged on radiography
Studies
Electrocardiogram (ECG) indications for all patients findings low voltage electrical alternans variations in the height of the QRS complex from swinging of the heart in the chest Right heart catheterization indication typically not performed as an initial test findings equilibration of pressures in all 4 chambers during diastole Making the diagnosis based on clinical presentation, ECG, echocardiogram, and chest radiography
Differential
Constrictive pericarditis distinguishing factors also has pulsus paradoxus, but also presents with Kussmaul sign increase (or absence of decline) in jugular venous pressure with inhalation pericardial knock Tension pneumothorax distinguishing factors decreased or absent breath sounds hyperresonant percussion
Treatment
Management approach all approaches focus on removal of the fluid in the pericardium Conservative close monitoring and volume expansion indication cardiac tamponade without hemodynamic compromise modalities serial echocardiographs intravenous bolus of fluids Procedural percutaneous pericardiocentesis indication first-line treatment Operative surgical drainage indications patients with coagulopathy or need for biopsy purulent pericarditis traumatic cardiac tamponade surgical drainage with pericardial window placement indication patients with chronic pericardial effusions patients who decompensate
Complications
Death

Blood, Plasma, Serum	Reference Range
ALT	8-20 U/L
Amylase, serum	25-125 U/L
AST	8-20 U/L
Bilirubin, serum (adult) Total // Direct	0.1-1.0 mg/dL // 0.0-0.3 mg/dL
Calcium, serum (Ca²⁺)	8.4-10.2 mg/dL
Cholesterol, serum	Rec: < 200 mg/dL
Cortisol, serum	0800 h: 5-23 μg/dL //1600 h: 3-15 μg/dL 2000 h: ≤ 50% of 0800 h
Creatine kinase, serum	Male: 25-90 U/L Female: 10-70 U/L
Creatinine, serum	0.6-1.2 mg/dL
Electrolytes, serum
Sodium (Na⁺)	136-145 mEq/L
Chloride (Cl^-)	95-105 mEq/L
Potassium (K⁺)	3.5-5.0 mEq/L
Bicarbonate (HCO₃^-)	22-28 mEq/L
Magnesium (Mg²⁺)	1.5-2.0 mEq/L
Estriol, total, serum (in pregnancy)
24-28 wks // 32-36 wks	30-170 ng/mL // 60-280 ng/mL
28-32 wk // 36-40 wks	40-220 ng/mL // 80-350 ng/mL
Ferritin, serum	Male: 15-200 ng/mL Female: 12-150 ng/mL
Follicle-stimulating hormone, serum/plasma	Male: 4-25 mIU/mL Female: premenopause: 4-30 mIU/mL midcycle peak: 10-90 mIU/mL postmenopause: 40-250
pH	7.35-7.45
PCO₂	33-45 mmHg
PO₂	75-105 mmHg
Glucose, serum	Fasting: 70-110 mg/dL 2-h postprandial:<120 mg/dL
Growth hormone - arginine stimulation	Fasting: <5 ng/mL Provocative stimuli: > 7ng/mL
Immunoglobulins, serum
IgA	76-390 mg/dL
IgE	0-380 IU/mL
IgG	650-1500 mg/dL
IgM	40-345 mg/dL
Iron	50-170 μg/dL
Lactate dehydrogenase, serum	45-90 U/L
Luteinizing hormone, serum/plasma	Male: 6-23 mIU/mL Female: follicular phase: 5-30 mIU/mL midcycle: 75-150 mIU/mL postmenopause 30-200 mIU/mL
Osmolality, serum	275-295 mOsmol/kd H₂O
Parathyroid hormone, serume, N-terminal	230-630 pg/mL
Phosphatase (alkaline), serum (p-NPP at 30° C)	20-70 U/L
Phosphorus (inorganic), serum	3.0-4.5 mg/dL
Prolactin, serum (hPRL)	< 20 ng/mL
Proteins, serum

Hematologic	Reference Range
Bleeding time	2-7 minutes
Erythrocyte count	Male: 4.3-5.9 million/mm³ Female: 3.5-5.5 million mm³
Erythrocyte sedimentation rate (Westergren)	Male: 0-15 mm/h Female: 0-20 mm/h
Hematocrit	Male: 41%-53% Female: 36%-46%
Hemoglobin A1c	≤ 6 %
Hemoglobin, blood	Male: 13.5-17.5 g/dL Female: 12.0-16.0 g/dL
Hemoglobin, plasma	1-4 mg/dL
Leukocyte count and differential
Leukocyte count	4,500-11,000/mm³
Segmented neutrophils	54%-62%
Bands	3%-5%
Eosinophils	1%-3%
Basophils	0%-0.75%
Lymphocytes	25%-33%
Monocytes	3%-7%
Mean corpuscular hemoglobin	25.4-34.6 pg/cell
Mean corpuscular hemoglobin concentration	31%-36% Hb/cell
Mean corpuscular volume	80-100 μm³
Partial thromboplastin time (activated)	25-40 seconds
Platelet count	150,000-400,000/mm³
Prothrombin time	11-15 seconds
Reticulocyte count	0.5%-1.5% of red cells
Thrombin time	< 2 seconds deviation from control
Volume
Plasma	Male: 25-43 mL/kg Female: 28-45 mL/kg
Red cell	Male: 20-36 mL/kg Female: 19-31 mL/kg

Cerebrospinal Fluid	Reference Range
Cell count	0-5/mm³
Chloride	118-132 mEq/L
Gamma globulin	3%-12% total proteins
Glucose	40-70 mg/dL
Pressure	70-180 mm H₂O
Proteins, total	< 40 mg/dL

Sweat	Reference Range
Chloride	0-35 mmol/L
Urine
Calcium	100-300 mg/24 h
Chloride	Varies with intake
Creatinine clearance	Male: 97-137 mL/min Female: 88-128 mL/min
Estriol, total (in pregnancy)
30 wks	6-18 mg/24 h
35 wks	9-28 mg/24 h
40 wks	13-42 mg/24 h
17-Hydroxycorticosteroids	Male: 3.0-10.0 mg/24 h Female: 2.0-8.0 mg/24 h
17-Ketosteroids, total	Male: 8-20 mg/24 h Female: 6-15 mg/24 h
Osmolality	50-1400 mOsmol/kg H₂O
Oxalate	8-40 μg/mL
Potassium	Varies with diet
Proteins, total	< 150 mg/24 h
Sodium	Varies with diet
Uric acid	Varies with diet
Body Mass Index (BMI)	Adult: 19-25 kg/m²