What stimulates the production of surfactant?

Purines, such as adenosine triphosphate are potent stimulators of surfactant secretion and may be important for its secretion at birth. Mechanical stretch such as lung distension and hyperventilation, have also been found to be involved in stimulating surfactant secretion.

What factors influence surfactant production?

The influence of the following hormones and other factors on lung maturation and surfactant production is discussed: glucocorticoids, thyroid hormone, estrogen, prolactin, cyclic AMP, beta-adrenergic and cholinergic agonists, prostaglandins and growth factors.

What increases pulmonary surfactant?

Surfactant protein C (SP-C) is a highly hydrophobic protein that enhances the surface tension-lowering properties of pulmonary surfactant.

Which genes influence the formation of pulmonary surfactant?

The SFTPB and SFTPC genes provide instructions for making surfactant protein-B (SP-B) and surfactant protein-C (SP-C), respectively, two of the four proteins in surfactant. These two proteins help spread the surfactant across the surface of the lung tissue, aiding in the surface tension-lowering property of surfactant.

Which cells produce surfactant quizlet?

Surfactant is a complex substance containing phospholipids and a number of apoproteins. This fluid is produced by the Type II alveolar cells, and lines the alveoli and smallest bronchioles.

Surfactant

What is the source of surfactant?

Surfactant is produced exclusively by alveolar type II epithelial cells and stored in specialized organelles called lamellar bodies (LBs) until it is secreted into the lumen of the alveolus. Secreted surfactant is recycled by type II cells to be repackaged and secreted again.

Does peep increase surfactant?

Abstract. Positive end expiratory pressure (PEEP) is routinely used when ventilating preterm infants, and high levels are recommended in those with severe respiratory distress syndrome (RDS). Elevation of PEEP increases lung volume, as does surfactant administration.

What are factors affecting surface tension?

Surface tension is caused by the effects of intermolecular forces at the interface. Surface tension depends on the nature of the liquid, the surrounding environment and temperature. Liquids where molecules have large attractive intermolecular force will have a large surface tension.

Which substances increase surface tension?

The surface tension of water, for example, will increase when highly soluble impurities are added to it. When detergent is added to water, it decreases the surface tension of the water. Compounds that lower water's surface tension are called surfactants, which work by separating the water molecules from one another.

Which of the following factors affect surface tension of liquid?

Notes: The Surface tension depends only on the nature of liquid and is independent of the area of surface or length of line considered. Surface tension of a liquid is measured by the force acting per unit length on either side of an imaginary line drawn on the free surface of liquid.

What is the cause of surface tension of a liquid?

The cohesive forces between liquid molecules are responsible for the phenomenon known as surface tension.

What is the purpose of PEEP?

The use of PEEP mainly has been reserved to recruit or stabilize lung units and improve oxygenation in patients who have hypoxemic respiratory failure. It has been shown that this helps the respiratory muscles to decrease the work of breathing and the amount of infiltrated-atelectatic tissues.

What happens if PEEP is too high?

Increasing PEEP to 10 and higher resulted in significant declines in cardiac output. A PEEP of 15 and higher resulted in significant declines in oxygen delivery.

What does a PEEP valve do?

A PEEP valve is simply a spring loaded valve that the patient exhales against. PEEP prevents ventilator induced lung injury – The loss of lung units taking part in gas exchange as a result of collapse at end expiration impairs oxygenation.

How is surfactant secreted?

Lung surfactant is synthesized in the alveolar type II cell. Its lipids and hydrophobic proteins (SP-B and SP-C) are stored in lamellar bodies and secreted by regulated exocytosis. In contrast, the hydrophilic proteins (SP-A and SP-D) appear to be secreted independently of lamellar bodies.

What cells produce surfactant in the respiratory tract?

Surfactant components are synthesized primarily by the alveolar type II cell, which produces surfactant lipids and surfactant proteins (5, 18), and the airway club cell, which synthesizes surfactant proteins SP-A, SP-B, and SP-D (19–21) (Figure 2).

Which lipid acts as lungs surfactant?

Phospholipids are the major lipid component of surfactant, especially dipalmitoylphosphatidylcholine (DPPC) (19, 20).

Why does BP drop after intubation?

Answer. Hypotension after intubation is usually attributable to diminished central venous blood return to the heart secondary to elevated intrathoracic pressures.

What is PEEP and PIP?

PEEP improves gas exchange by increasing the functional residual capacity, reduces the respiratory effort, lowers requirements for respiratory mixture oxygen, and enables to decrease the peak inspiratory pressure (PIP) without decreasing the mean airway pressure.

Does PEEP decrease preload?

While PEEP decreases RV preload by impairing systemic venous return, it will also increase RV afterload.

Does PEEP increase tidal volume?

Upper panel: An increase in tidal volume (V_T) at a given constant positive end-expiratory pressure (PEEP) increases the ventilation in the dependent parts of the lung by recruiting atelectatic lung regions (reduction of the dark grey oval symbols).

Does PEEP increase or decrease blood pressure?

Our study found that when PEEP was below 4 cm H₂O in the both control and hypertension groups, blood pressure was unaffected by PEEP. However, when PEEP was above 4 cm H₂O, the increase in PEEP led to decreased blood pressure and PEEP was negatively correlated with blood pressure in the hypertension group.

How does PEEP affect co2?

Introduction: In a previous study of anesthetized dogs, positive end-expiratory pressure (PEEP) decreased CO ₂ volume exhaled per breath (V _{CO 2},br) by increasing physiological dead space (VD _phy) and by decreasing cardiac output (QT, decreased CO ₂ delivery to the lung).

Which of the following is the reason for the property of surface tension?

Surface tension is the property of a liquid by virtue of which, the surface of a liquid acts like a stretched membrane thereby acquiring the least possible surface area. This property is attributed to the cohesive forces between the molecules of the liquid.

How do you increase surface tension?

By adding something more polar than water to water, the surface tension would increase (just as doing the opposite decreases surface tension).