February 23, 2024

Determination of tidal volume and vital capacity: Human Anatomy Physiology Practical

Determination of tidal volume and vital capacity: Human Anatomy Physiology Practical

Aim:

To determine the tidal volume and vital capacity.

Requirements:

Spirometer; potassium permanganate solution.

Theory:

The spirometer consists of a double-walled metal cylindrical chamber, with a light metal gas bell of 6 litres capacity floating in an outer container filled with water. The water acts as an airtight seal. The bell is attached to a chain on its upper end which passes over a graduated frictionless pulley. The pulley has a spring-mounted indicator needle that indicates the volume of air present in the bell. The gas bell is counterbalanced by a weight attached to the other end of the chain for a smooth up and down movement of the bell. The inlet tube is a corrugated canvas-rubber tube with a mouthpiece through which air moves into or out of the bell. This tube is attached to a metal pipe at the bottom of the spirometer. When air is blown into the inlet tube, it raises the bell in the container.

Vital Capacity (VC) is the largest volume of air that a person can expel from the lungs by forceful expiration after forceful inspiration. It can be measured using a breath measuring device called a spirometer (simple or recording). A simple spirometer is a low-cost and conventional instrument commonly used on the laboratory scale whereas a recording spirometer is a sophisticated, electrically-driven instrument with a recording system and widely used in respiratory physiology laboratories and hospitals.

The graphical recording of the spirometer is called a spirogram in which inspiration is recorded as an upward deflection and expiration as a downward deflection.

Calibrated pulley

The volume of air in the lungs changes considerably during a respiratory cycle which can be distinguished as four different lung volumes:

  1. Tidal Volume (TV): It is the amount of air that moves into the lungs with each inspiration (or the amount that moves out with each expiration) during normal breathing (tidal respiration). Normal TV is about 500 ml
  2. Inspiratory Reserve Volume (IRV): It is the volume of additional inhaled air during deep breathing. It is about 3100 ml above the TV.
  3. Expiratory Reserve Volume (ERV): It is the extra volume of exhaled air during forced expiration. It is about 1200 ml in addition to the TV.
  4. Residual Volume (RV): It is the volume of air remaining in the lungs after the expulsion of ERV. It amounts to about 1200 ml. The combination of specific lung volumes gives lung capacities. The vital capacity (VC) is the total amount of air that can be exchanged between the atmosphere and lungs during normal and forced respiration. It is calculated as:

Vital capacity (VC) (4800 ml) = IRV (3100 ml) + TV (500 ml) + ERV (1200 ml)

Normal vital capacity ranges between 3.5 and 6 litres. It is used clinically as an index of lung function and gives information about abnormal ventilation due to respiratory diseases.

Procedure:

  1. Select one healthy subject for the demonstration.
  2. Bring the bell to its lowest position by gently pushing it down. Adjust the pointer needle to zero, which indicates that the bell is completely empty.
  3. Make the subject stand comfortably, facing the spirometer to see the movement of the bell

Measurement of Vital Capacity:

  1. After normal breathing for one minute, ask the subject to breathe as deeply and forcibly as possible to fill the lungs.
  2. Ask him/her to close both the nostrils with a thumb and fingers, and hold the mouthpiece firmly between the lips.
  3. In this position, ask to expel all the air with maximum effort into the spirometer. The bell moves up and the pointer on the pulley indicates the volume of expired air (The forced expiration should be deep and quick but without excessive speed).
  4. Take two more readings at intervals of 5 minutes.
  5. Repeat this procedure in a sitting position.

Measurement of Tidal Volume:

  1. Ask the subject to breathe normally (quiet breathing) for the period of one minute.
  2. Ask him/her to close both the nostrils with a thumb and fingers, and hold the mouthpiece firmly between the lips.
  3. In this position, ask him/hers to expel the air with normal expiration. The bell moves up and the pointer on the pulley indicates the volume of expired.
  4. Take two more readings at intervals of 5 minutes.
  5. Repeat this procedure in a sitting position.
Sl. No.ParametersVital CapacityTidal volume
 StandingSitting/StandingSitting/Standing
11st  reading  
22nd    reading  
33rd    reading  
4Mean  
What is the difference between tidal volume and vital capacity

Tidal volume and vital capacity are both measurements related to lung function, but they represent different aspects of respiratory physiology. Here’s a breakdown of the difference between tidal volume and vital capacity:

Tidal Volume:
Tidal volume (TV) refers to the volume of air that is inhaled or exhaled during normal breathing, typically in a single breath. It represents the amount of air that moves in and out of the lungs during each respiratory cycle without any additional effort. Tidal volume is relatively constant during quiet, resting breathing and is typically measured in milliliters (mL) or liters (L).

Vital Capacity:
Vital capacity (VC) is a measure of the maximum amount of air a person can exhale after taking the deepest possible inhalation. It represents the total volume of air that can be moved in and out of the lungs during a complete respiratory cycle, including both the tidal volume and additional volumes achieved with forced inspiration and forced expiration. Vital capacity is used as an indicator of lung function and respiratory muscle strength. It is typically measured in liters (L).

Vital capacity can be subdivided into three primary components:

Tidal Volume: As mentioned earlier, it is the volume of air moved during normal breathing.
Inspiratory Reserve Volume (IRV): This represents the additional volume of air that can be inhaled after a normal inhalation.
Expiratory Reserve Volume (ERV): This refers to the additional volume of air that can be exhaled forcefully after a normal exhalation.

To calculate vital capacity, you add together the tidal volume, inspiratory reserve volume, and expiratory reserve volume:
Vital Capacity = Tidal Volume + Inspiratory Reserve Volume + Expiratory Reserve Volume
It’s worth noting that tidal volume and vital capacity can vary among individuals based on factors such as age, sex, body size, and overall lung health. These measurements are commonly used in pulmonary function tests to assess lung function, diagnose respiratory conditions, and monitor respiratory health.

What is normal vital capacity in Ml

The normal vital capacity (VC) can vary depending on factors such as age, sex, height, and overall lung health. However, as a general guideline, the average vital capacity for adult males is typically around 4,000-5,000 milliliters (ml) or 4-5 liters (L), while for adult females, it is usually around 3,000-4,000 ml or 3-4 liters.


BP207P Human Anatomy and Physiology II Practical

To study the integumentary and special senses using specimens, models, etc.,
To study the nervous system using specimens, models, etc.,
To study the endocrine system using specimens, models, etc
To demonstrate the general neurological examination
To demonstrate the function of olfactory nerve
To examine the different types of taste.
To demonstrate the visual acuity
To demonstrate the reflex activity
Recording of body temperature
Determination of tidal volume and vital capacity.
Study of digestive, respiratory, cardiovascular systems, urinary and reproductive systems with the help of models, charts and specimens.
Recording of the basal mass index.
Study of family planning devices and pregnancy diagnosis test.
Demonstration of total blood count by cell analyzer
Permanent slides of vital organs and gonads


First Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise

F Y B Pharm Sem-IF Y B Pharm Sem-II
BP101T Human Anatomy and Physiology I TheoryBP201T Human Anatomy and Physiology II – Theory
BP102T Pharmaceutical Analysis I TheoryBP202T Pharmaceutical Organic Chemistry I Theory
BP103T Pharmaceutics I TheoryBP203T Biochemistry – Theory
BP104T Pharmaceutical Inorganic Chemistry TheoryBP204T Pathophysiology – Theory
BP105T Communication skills TheoryBP205T Computer Applications in Pharmacy Theory
BP106RBT Remedial BiologyBP206T Environmental sciences – Theory
BP106RMT Remedial Mathematics TheoryBP207P Human Anatomy and Physiology II Practical
BP107P Human Anatomy and Physiology PracticalBP208P Pharmaceutical Organic Chemistry I Practical
BP108P Pharmaceutical Analysis I PracticalBP209P Biochemistry Practical
BP109P Pharmaceutics I PracticalBP210P Computer Applications in Pharmacy Practical
BP110P Pharmaceutical Inorganic Chemistry Practical
BP111P Communication skills Practical
BP112RBP Remedial Biology Practical

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