Hemothorax

Overview

Definition

A hemothorax is defined as a collection of fluid with a hematocrit Hematocrit The volume of packed red blood cells in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, anemia shows a low value; polycythemia, a high value. Neonatal Polycythemia of at least 50% accumulated in the potential space between the parietal Parietal One of a pair of irregularly shaped quadrilateral bones situated between the frontal bone and occipital bone, which together form the sides of the cranium. Skull: Anatomy and visceral pleura Visceral pleura Pleura: Anatomy of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy.

Epidemiology

• In the United States, an estimated 300,000 cases are reported annually.
• Associated with chest trauma and particularly motor vehicle accidents Motor Vehicle Accidents Spinal Cord Injuries
• Chest trauma seen in 60% of polytrauma Polytrauma Multitrauma occurs when 2 or more traumatic injuries occur in at least 2 areas of the body. A systematic management approach is necessary for individuals who have undergone trauma to maximize outcomes and reduce the risk of undiscovered injuries. Multitrauma

Etiology

The source of blood may be the chest wall Chest wall The chest wall consists of skin, fat, muscles, bones, and cartilage. The bony structure of the chest wall is composed of the ribs, sternum, and thoracic vertebrae. The chest wall serves as armor for the vital intrathoracic organs and provides the stability necessary for the movement of the shoulders and arms. Chest Wall: Anatomy, lung parenchyma, heart, or great vessels from either traumatic or non-traumatic causes.

Traumatic causes:

• Lung parenchymal injury Lung Parenchymal Injury Thoracic Trauma in Children:
  • Most common cause
  • More commonly small (< 10%)
  • Often self-limited
• Arterial injury:
  • Intercostal artery injury (most common)
  • Internal mammary artery injury
  • Great large vessels (rare, but life threatening)
• Iatrogenic Iatrogenic Any adverse condition in a patient occurring as the result of treatment by a physician, surgeon, or other health professional, especially infections acquired by a patient during the course of treatment. Anterior Cord Syndrome:
  • Central venous catheter Central Venous Catheter Central venous catheters are IV lines placed into the large central veins for monitoring of central venous pressure (CVP), prolonged drug administration, or administration of parenteral nutrition. The most common sites of insertion are the internal jugular and subclavian veins. Central Venous Catheter placement
  • Thoracostomy tube placement Tube placement Surgical procedure involving the creation of an opening (stoma) into the chest cavity for drainage; used in the treatment of pleural effusion; pneumothorax; hemothorax; and empyema. Thoracic Surgery

Non-traumatic causes:

• Malignancy
• Anticoagulant medications
• Coagulopathies
• Aortic dissection Aortic dissection Aortic dissection occurs due to shearing stress from pulsatile pressure causing a tear in the tunica intima of the aortic wall. This tear allows blood to flow into the media, creating a “false lumen.” Aortic dissection is most commonly caused by uncontrolled hypertension. Aortic Dissection or aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Thoracic Aortic Aneurysms
• Tuberculosis Tuberculosis Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis and necrotizing infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease

Pathophysiology

Hemodynamic component:

Large volume loss (each hemothorax can contain up to 40% of total circulating blood volume) into the pleura Pleura The pleura is a serous membrane that lines the walls of the thoracic cavity and the surface of the lungs. This structure of mesodermal origin covers both lungs, the mediastinum, the thoracic surface of the diaphragm, and the inner part of the thoracic cage. The pleura is divided into a visceral pleura and parietal pleura. Pleura: Anatomy can lead to decreased cardiac function due to:

• Decreased preload Preload Cardiac Mechanics by constricting the vena cava
• Increased restriction of movement of the cardiac wall
• Increased hydrostatic pressure Hydrostatic pressure The pressure due to the weight of fluid. Edema leading to pulmonary hypertension Pulmonary Hypertension Pulmonary hypertension (PH) or pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary arterial pressure, which can lead to chronic progressive right heart failure. Pulmonary hypertension is grouped into 5 categories based on etiology, which include primary PAH, and PH due to cardiac disease, lung or hypoxic disease, chronic thromboembolic disease, and multifactorial or unclear etiologies. Pulmonary Hypertension

Respiratory component:

Blood collecting in the pleura Pleura The pleura is a serous membrane that lines the walls of the thoracic cavity and the surface of the lungs. This structure of mesodermal origin covers both lungs, the mediastinum, the thoracic surface of the diaphragm, and the inner part of the thoracic cage. The pleura is divided into a visceral pleura and parietal pleura. Pleura: Anatomy decreases the lung’s functional vital capacity Vital capacity The volume of air that is exhaled by a maximal expiration following a maximal inspiration. Ventilation: Mechanics of Breathing by:

• Causing hypoventilation (decreased tidal volume Tidal volume The volume of air inspired or expired during each normal, quiet respiratory cycle. Common abbreviations are tv or V with subscript t. Ventilation: Mechanics of Breathing)
• Creating ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing/perfusion (V/Q) mismatch
• Leading to anatomic shunting

Clinical Presentation

Symptoms

• Shortness of breath Shortness of breath Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea
• Chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways

Signs

• Ipsilateral absent or ↓ breath sounds
• Tracheal deviation Tracheal Deviation Pneumothorax
• Dullness on percussion Percussion Act of striking a part with short, sharp blows as an aid in diagnosing the condition beneath the sound obtained. Pulmonary Examination
• Crepitus Crepitus Osteoarthritis
• Signs of hemorrhagic shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock in large hemothoraces:
  • Hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension
  • Tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children
  • Tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination
  • ↓ Jugular venous pressure Jugular Venous Pressure Portal Hypertension

Diagnosis

Diagnosis is established by utilizing history, physical, and appropriate imaging. In cases of trauma, use of the primary survey Primary Survey Thoracic Trauma in Children is paramount to rapid diagnosis and treatment.

Imaging

• Chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests: best initial diagnostic study
  • Upright imaging shows layering of blood.
  • Supine imaging shows haziness or opacity Opacity Imaging of the Lungs and Pleura (whiteout).
  • May also show free air if a pneumothorax Pneumothorax A pneumothorax is a life-threatening condition in which air collects in the pleural space, causing partial or full collapse of the lung. A pneumothorax can be traumatic or spontaneous. Patients present with a sudden onset of sharp chest pain, dyspnea, and diminished breath sounds on exam. Pneumothorax is present
• Ultrasound of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy (thorax sonography Sonography The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1. 6 to 10 megahertz. Diagnostic Procedures in Gynecology):
  • Part of the Extended Focused Assessment with Sonography Sonography The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1. 6 to 10 megahertz. Diagnostic Procedures in Gynecology for Trauma (eFAST) exam
  • Able to be obtained quickly
  • Can show complex fluid in the pleural cavity Pleural cavity Paired but separate cavity within the thoracic cavity. It consists of the space between the parietal and visceral pleura and normally contains a capillary layer of serous fluid that lubricates the pleural surfaces. Pleura: Anatomy
  • More sensitive than a chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests in detecting a hemothorax, but is technician dependent
• Chest computed tomography(CT)—definitive imaging choice:
  • Should only be obtained if the patient is stable 
  • CT can show other associated pathology.
  • CT angiogram CT angiogram A non-invasive method that uses a ct scanner for capturing images of blood vessels and tissues. A contrast material is injected, which helps produce detailed images that aid in diagnosing vascular diseases. Pulmonary Function Tests can show the source of bleeding.

Management and Complications

Management

• Airway Airway ABCDE Assessment, breathing, and circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment (ABC) assessment → administer 100% oxygen 100% Oxygen Cluster Headaches → establish intravenous (IV) access
• Stabilize the patient (fluid resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome and blood transfusion as necessary).
• Reverse anticoagulants Anticoagulants Anticoagulants are drugs that retard or interrupt the coagulation cascade. The primary classes of available anticoagulants include heparins, vitamin K-dependent antagonists (e.g., warfarin), direct thrombin inhibitors, and factor Xa inhibitors. Anticoagulants, if necessary.
• Provide analgesia Analgesia Methods of pain relief that may be used with or in place of analgesics. Anesthesiology: History and Basic Concepts appropriate to the level of the patient’s pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways.
• Insert a chest tube (thoracostomy) for large hemothoraces or in an unstable patient:
  • Chest tube inserted on the midaxillary line Midaxillary Line Examination of the Breast at the 5th intercostal space
  • Used to drain the hemothorax
  • Monitor output of the hemothorax.
• Surgical intervention ( thoracotomy Thoracotomy Surgical incision into the chest wall. Thoracic Surgery) is indicated when:
  • Evacuating > 1,500 mL of blood directly after inserting a chest tube
  • Continued high output → collecting of > 1 L (1,000 mL) of blood over 4 hours or > 200 mL/hour for 3 consecutive hours

Complications

• Impaired ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing on the affected side:
  • Leads to respiratory distress
  • May require intubation Intubation Peritonsillar Abscess
• Empyema Empyema Presence of pus in a hollow organ or body cavity. Pneumonia:
  • Retained blood collection develops a bacterial infection.
  • 5% of cases
• Fibrothorax:
  • Formation of scar Scar Dermatologic Examination tissues within the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy due to blood irritation
  • 1% of cases

Differential Diagnosis

• Pneumothorax Pneumothorax A pneumothorax is a life-threatening condition in which air collects in the pleural space, causing partial or full collapse of the lung. A pneumothorax can be traumatic or spontaneous. Patients present with a sudden onset of sharp chest pain, dyspnea, and diminished breath sounds on exam. Pneumothorax: abnormal collection of air in the pleural space Pleural space The thin serous membrane enveloping the lungs (lung) and lining the thoracic cavity. Pleura consist of two layers, the inner visceral pleura lying next to the pulmonary parenchyma and the outer parietal pleura. Between the two layers is the pleural cavity which contains a thin film of liquid. Pleuritis due to laceration Laceration Torn, ragged, mangled wounds. Blunt Chest Trauma of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy. Types of pneumothorax Pneumothorax A pneumothorax is a life-threatening condition in which air collects in the pleural space, causing partial or full collapse of the lung. A pneumothorax can be traumatic or spontaneous. Patients present with a sudden onset of sharp chest pain, dyspnea, and diminished breath sounds on exam. Pneumothorax include spontaneous pneumothorax Pneumothorax A pneumothorax is a life-threatening condition in which air collects in the pleural space, causing partial or full collapse of the lung. A pneumothorax can be traumatic or spontaneous. Patients present with a sudden onset of sharp chest pain, dyspnea, and diminished breath sounds on exam. Pneumothorax and traumatic pneumothorax Traumatic Pneumothorax Pneumothorax. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship have dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea, chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, decreased breath sounds, and hyper-resonance Hyper-Resonance Pneumothorax on percussion Percussion Act of striking a part with short, sharp blows as an aid in diagnosing the condition beneath the sound obtained. Pulmonary Examination. Treatment includes needle decompression Needle Decompression Pneumothorax and chest tube placement Tube placement Surgical procedure involving the creation of an opening (stoma) into the chest cavity for drainage; used in the treatment of pleural effusion; pneumothorax; hemothorax; and empyema. Thoracic Surgery.
• Pleural effusion Pleural Effusion Pleural effusion refers to the accumulation of fluid between the layers of the parietal and visceral pleura. Common causes of this condition include infection, malignancy, autoimmune disorders, or volume overload. Clinical manifestations include chest pain, cough, and dyspnea. Pleural Effusion: accumulation of fluid in the pleural cavity Pleural cavity Paired but separate cavity within the thoracic cavity. It consists of the space between the parietal and visceral pleura and normally contains a capillary layer of serous fluid that lubricates the pleural surfaces. Pleura: Anatomy. Can be caused by many conditions, including infection, malignancy, and heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR). Symptoms include chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea, and orthopnea Orthopnea Pulmonary Edema. Diagnosis is by imaging, and pleural fluid analysis helps determine the etiology. Management is dependent on the underlying condition and severity, but may include monitoring, thoracentesis Thoracentesis Aspiration of fluid or air from the thoracic cavity. It is coupled sometimes with the administration of drugs into the pleural cavity. Thoracic Surgery, chest tube placement Tube placement Surgical procedure involving the creation of an opening (stoma) into the chest cavity for drainage; used in the treatment of pleural effusion; pneumothorax; hemothorax; and empyema. Thoracic Surgery, or surgery.
• Atelectasis Atelectasis Atelectasis is the partial or complete collapse of a part of the lung. Atelectasis is almost always a secondary phenomenon from conditions causing bronchial obstruction, external compression, surfactant deficiency, or scarring. Atelectasis: condition characterized by the collapse of alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS), and eventually, lobar lung collapse and complete obstruction. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with respiratory distress ( dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea, tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination, tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children) and hypoxemia Hypoxemia Neonatal Respiratory Distress Syndrome. Physical examination of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy reveals dullness to percussion Percussion Act of striking a part with short, sharp blows as an aid in diagnosing the condition beneath the sound obtained. Pulmonary Examination and decreased breath sounds. Chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests shows lung opacification. Management is aimed at ventilatory support. 
• Pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism (PE): obstruction of pulmonary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology, most often due to thrombus migration from the deep venous system. Signs and symptoms include pleuritic chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea, tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination, and tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children. Severe cases are life threatening. Chest CT with angiography Angiography Radiography of blood vessels after injection of a contrast medium. Cardiac Surgery is the primary method of diagnosis. Management includes oxygenation, anticoagulation Anticoagulation Pulmonary Hypertension Drugs, and thrombolytic therapy for unstable patients Unstable Patients Blunt Chest Trauma.