pleural cavity

Examples of pleural cavity in the following topics:

• Inspiration

  • Inspiration begins with the contraction of the diaphragm, which results in expansion of the thoracic cavity and the pleural cavity.
  • The pleural cavity normally has a lower pressure compared to ambient air (-3 mmHg normally and typically -6 mmHg during inspiration), so when it expands, the pressure inside the lungs drops.
  • As the volume of air inside the lung increases, the lung pushes back against the expanded pleural cavity as a result of the drop in intrapleural pressure (pressure inside the pleural cavity).
  • External intercostal muscles: muscles located in between the ribs that help the thoracic cavity (and thus pleural cavity) to expand during quiet and forced inspiration.
  • However, they expand a much smaller part of the thoracic cavity compared to diaphragm.

• Serous Membranes

  • The pericardial cavity (surrounding the heart), pleural cavity (surrounding the lungs), and peritoneal cavity (surrounding most organs of the abdomen) are the three serous cavities within the human body.
  • The pericardial cavity (surrounding the heart), pleural cavity (surrounding the lungs) , and peritoneal cavity (surrounding most organs of the abdomen) are the three serous cavities within the human body .
  • While serous membranes have a lubricative role to play in all three cavities, in the pleural cavity it plays a greater role in the function of breathing.
  • The pleural and pericardial cavities are exaggerated since normally there is no space between parietal and visceral pleura and between pericardium and heart.
  • Describe the function of the serous membranes in the pericardial, pleural, and peritoneal cavities

• Serosa

  • Serous membranes line and enclose several body cavities, known as serous cavities, where they secrete a lubricating fluid to reduce friction from muscle movements.
  • The pericardial cavity (surrounding the heart), pleural cavity (surrounding the lungs) and peritoneal cavity (surrounding most organs of the abdomen) are the three serous cavities within the human body.
  • While serous membranes have a lubricative role to play in all three cavities, in the pleural cavity it has a greater role to play in the function of breathing.
  • Early in embryonic life, visceral organs develop adjacent to a cavity and invaginate into the bag-like coelom.
  • Therefore each organ becomes surrounded by a serous membrane—they do not lie within the serous cavity.

• Lungs

  • The pleural cavity is the fluid-filled space between the parietal and visceral pleura, and provides room for the lung to expand during inhalation.
  • The fluid inside the pleural cavity protects against irritation during inhalation as well.
  • This is a transverse view of the thoracic cavity, showing the pleural cavity and the major structures around the lungs.
  • The human lungs flank the heart and great vessels in the chest cavity
  • The human lungs flank the heart and great vessels in the chest cavity.

• Expiration

  • Just as the plueral cavity's increased negative pressure leads to air uptake during inhalation, the pleural cavity will contract during the exhalation (due to relaxation of the diaphragm),which exerts pressure on the lungs and causes the pressure inside the cavity to be less negative.
  • The pleural cavity is so important to breathing because it's pressure changes the volume of the lungs, and it provides a friction-less space for the lung to expand and contract against during breathing.
  • Internal Intercostal Muscles: Muscles of the ribcage that help lower the ribcage, which pushes down on the thoracic cavity, causing forced exhalation.
  • Abdominal Muscles: Any number of muscles in the abdomen that exert pressure on the diaphragm from below to expand it, which in turn contracts the thoracic cavity, causing forced exhalation.
  • As the diaphragm relaxes, the pleural cavity contracts, which exerts pressure on the lungs, which reduces the volume of the lungs as air is passively pushed out of the lungs.

• Body Cavities

  • Blood vessels are not considered cavities but may be held within cavities.
  • The dorsal cavity is a continuous cavity located on the dorsal side of the body.
  • The abdominoplevic cavity is the posterior ventral body cavity found beneath the thoracic cavity and diaphragm.
  • Humans have multiple body cavities, including the cranial cavity, the vertebral cavity, the thoracic cavity (containing the pericardial cavity and the pleural cavity), the abdominal cavity, and the pelvic cavity.
  • In mammals, the diaphragm separates the thoracic cavity from the abdominal cavity.

• Factors Affecting Pulmonary Ventilation: Compliance of the Lungs

  • Compliance is the ability of lungs and pleural cavity to expand and contract based on changes in pressure.
  • A stiff lung would need a greater-than-average change in pleural pressure to change the volume of the lungs, and breathing becomes more difficult as a result.
  • This indicates that little pressure difference in pleural pressure is needed to change the volume of the lungs.

• Pneumothorax and Hemothorax

  • Pneumothorax, or collapsed lung, is an abnormal collection of air or gas in the pleural space of the lung that interferes with breathing.
  • A hemothorax is a condition that results from blood accumulating in the pleural cavity.
  • This rupture allows blood to spill into the pleural space, equalizing the pressures between it and the lungs.
  • A hemothorax is managed by removing the source of bleeding and by draining the blood already in the thoracic cavity.
  • Blood in the cavity can be drained using a chest tube.

• Pericardium

  • The pericardium is one of the mesothelium tissues of the thoracic cavity, along with the pleura which cover the lungs.
  • It prevents the heart from overfilling with blood and protects it from nearby infections by completely separating it from the rest of the thoracic cavity.
  • The space between the parietal and visceral layers is called the pericardial cavity.
  • The space between these two serous layers, the parietal and the visceral, is the pericardial cavity, which contains pericardial fluid.
  • The pleural and pericardial cavities are exaggerated since normally there is no space between parietal and visceral pleura and between pericardium and heart.

• Edema

  • Edema is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling.
  • For example, severe heart failure can cause pulmonary edema, pleural effusions, ascites, and peripheral edema.
  • Edema is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling.
  • For example, severe heart failure can cause pulmonary edema, pleural effusions, ascites, and peripheral edema.