Respiratory system laboratory.pptx

MEDICAL

1. ADVANCED AHN 1 CARE OF PATIENT WITH ACUTE CONDITIONS OF RESPIRATORY SYSTEM DISORDERS PRESENTATION ON “ PULMONARY FUNCTION TEST & RESPIRATORY LAB STUDIES” By Demiso G . (BSc , MSc in AHN student) 27-Jul-22 PFT & Its lab studies 1

2. Objectives 27-Jul-22 PFT & Its lab studies 2 Define pulmonary function test Interpret each types of pulmonary function test Interpret and collecting sputum Evaluating and collecting plural effusion Collecting and interpret arterial blood gas analysis

3. Outline 27-Jul-22 PFT & Its lab studies 3 Pulmonary function test Lab studies (respiratory): Sputum test Thoracentesis ABG analysis

4. Brainstorming 27-Jul-22 PFT & Its lab studies 4 What are lung function tests ?

5. Pulmonary function test Lung function tests, also known as pulmonary function tests ( PFTs), are a group of tests that check to see if your lungs are working right. The tests look for: How much air your lungs can hold How well you move air in and out of your lungs How well the lungs move oxygen into your bloodstream. Your blood cells need oxygen to grow and stay healthy. 27-Jul-22 PFT & Its lab studies 5

6. Indications of PFT 27-Jul-22 PFT & Its lab studies 6 Pulmonary Evaluation: ƒ Presence of impairment ƒ Type of Pulmonary dysfunction ƒ Monitor the progression of known disease ƒ Monitor the treatment response of known disease Preoperative Assessment: ƒ Estimate the risk for postoperative complications ƒ Tolerance for lung resection ( resectability ) Disability Evaluation

7. PFT is recommend for patient having symptom 27-Jul-22 PFT & Its lab studies 7 Shortness of breath Coughing Coughing up mucus or phlegm Wheezing Difficulty breathing Fatigue History of smoking

8. Pulmonary Function Tests includes : 27-Jul-22 PFT & Its lab studies 8 ‰ Spirometry ‰ Lung Volumes ‰ Diffusion Capacity ‰ Maximal Voluntary Ventilation (MVV) ‰ Maximal Inspiratory Pressure (Pi max) ‰ Maximal Expiratory Pressure ( Pe max) ‰ Arterial Blood Gas (ABG) ‰ Walking Oxymetry ‰ Broncho challenge Tests

9. An approach to PFT interpretation 27-Jul-22 PFT & Its lab studies 9 C onfirm patient demographic data Interpretation involves comparison of the patient’s values with reference values:- Depend on age, sex, race and ethnicity, height African Americans have values that are 12% lower than Caucasians Threshold for Normal FEV1/FVC 80-120% predicted Age-adjusted lower limits of normal

10. An approach to PFT interpretation…. 27-Jul-22 PFT & Its lab studies 10 Measures the lung volume change during forced breathing maneuvers: Forced vital capacity (FVC) – amount of air that can be exhaled in 1breath with maximum force Forced expiratory volume in 1sec (FEV1 ) Measure of airflow = FEV1/FVC ratio Peak flow rate (PEF, PEFR) – highest flow rate achieved during expiration

11. Flow volume loops 27-Jul-22 PFT & Its lab studies 11 The FEV1/FVC ratio changes with age The FEV1/FVC ratio declines in normal people as they get older ‒ An average FEV1/FVC in a 20 year old is 87% ‒ An average FEV1/FVC in an 84 year old is 71% The lower limit of normal in an 84 year old is 59%!

12. Flow volume loops…. 27-Jul-22 PFT & Its lab studies 12 If the FEV1/FVC ratio is normal, then the patient is NOT obstructed. Obstruction is present if the FEV1/FVC ratio is reduced . Reversible obstruction‒ 12% increase and 200 mL increase in FVC or FEV1with bronchodilator

13. 1, Lung volume test This test measures the amount of air you can hold in your lungs and the amount of air that remains after you exhale (breathe out) You will be asked to wear a nose clip and you will be given instruction on how to breathe through a mouthpiece. The test takes about 15 minutes. 27-Jul-22 PFT & Its lab studies 13

14. 2. Lung volumes and capacities 27-Jul-22 PFT & Its lab studies 14

15. Lung volumes & capacities…. 27-Jul-22 PFT & Its lab studies 15 Tidal Volume (VT):The volume of air entering the nose or mouth per breath (500 ml ) Residual Volume (RV): The volume of air left in the lungs after a maximal forced expiration(1.5L) Expiratory Reserve Volume (ERV): The volume of air that is expelled from the lung during a maximal forced expiration that starts at the end of normal tidal expiration (1.5L ) Inspiratory Reserve Volume (IRV ): The volume of air that is inhaled into the lung during a maximal forced inspiration starting at the end of a normal tidal inspiration (2.5L )

16. Lung volumes & capacities…. 27-Jul-22 PFT & Its lab studies 16 Functional Residual Capacity (FRC): the volume of air remaining in the lungs at the end of a normal tidal expiration ( 3L) Vital Capacity (VC): The volume of air that is expelled from the lung during a maximal forced expiration effort starting after a maximal forced inspiration (4.5L ) Total Lung Capacity (TLC): The volume of air that is inhaled into the lung after a maximal inspiration effort (5-6 L ) Inspiratory Capacity (IC): The volume of air that is inhaled into the lung during a maximal forced inspiration effort that begins at the end of a normal tidal expiration (VT+IRV=3L )

17. 3. Spirometry T he most common type of lung function test. It measures how much and how quickly you can move air in and out of your lungs So called measure of airflow During this test, you forcefully exhale and then inhale into a tube connected to a machine called a spirometer . The spirometer measures the amount of air you blew out of your lungs and then inhaled back into your lungs. 27-Jul-22 PFT & Its lab studies 17

18. Spirometry….. You will be asked to repeat this test two or three times to get an accurate measure of your lung function. It takes approximately 30 minutes to complete this test . 27-Jul-22 PFT & Its lab studies 18

19. Indications For Spirometry Evaluation of unexplained dyspnea, cough, or wheezing Suspected COPD or asthma with no previous spirometry Known asthma or COPD with uncertain control Known asthma or COPD when assessing response to treat. Periodic assessment (every 1-2 years) of asthma to assess for changes in therapy Assessment of vital capacity in patients with known NMD. Pre-operative assessment in patients with known or suspected lung disease 27-Jul-22 PFT & Its lab studies 19

20. Interpret the PFTS with a systematic approach 27-Jul-22 PFT & Its lab studies 20 Patterns of disease with LFT is divided into three:- Obstructive FEV1/FVC < 0.7 ( or <LLN ):- These diseases cause airways to become narrow, making it hard for air to flow out of the lungs. Restrictive FEV1/FVC reduced with low lung volumes B ecause of the lungs or chest muscles aren't able to expand enough. This reduces air flow and the ability to send oxygen into the bloodstream. Mixed are both obstructive and restrictive

21. ….. 27-Jul-22 PFT & Its lab studies 21

22. Obstructive Lung Diseases: ‰ Emphysema & Chronic Bronchitis ( COPD ) ‰Cystic Fibrosis ‰ Asthma ‰ Bronchiectasis ‰ Some Interstitial Lung Disease: (combined ) 27-Jul-22 PFT & Its lab studies 22

23. ™ Restrictive Lung Diseases: CHF Atelectasis Fibrosis Tumor Pregnancy and obesity Kyphosis Ascites and infusion Goal : to evaluate the reversibility of the airway obstruction. 27-Jul-22 PFT & Its lab studies 23

24. Spirometry Interpretation The normal value of FEV1 and FVC vary depending on: 1. Age 2. Gender 3. Race 4. Height The FEV1/FVC is within a normal range 74%). 28-Jul-22 PFT & Its lab studies 24

25. 4. Gas diffusion capacity test: This test measures how oxygen and other gases move from the lungs to the bloodstream. Measure of gas exchange across the alveolar/capillary membrane Affected by age, body size, gender, hemoglobin, and lung volume Measured by carbon monoxide uptake You'll wear a mouthpiece connected to a machine 27-Jul-22 PFT & Its lab studies 25

26. Gas diffusion capacity test…. 27-Jul-22 PFT & Its lab studies 26 Measurements will either be taken as you breathe in or as you breathe out You will be asked to inhale (breathe in) a very small, non-dangerous amount of CO2 or other type of gas.

27. Gas diffusion capacity test…. 27-Jul-22 PFT & Its lab studies 27 Decreased Diffusing Capacity Anemia Right-left intracardiac shunt Poor inspiration Interstitial lung disease Emphysema Pulmonary vascular disease

28. 5. Exercise stress test. 27-Jul-22 PFT & Its lab studies 28 This test looks at how exercise affects lung function. These tests may be used together or by themselves, depending on your specific symptoms or condition You'll be attached to monitors and machines that will measure blood oxygen, blood pressure, and heartbeat. This helps show how well your lungs perform during exercise Goal : detects the hidden diffusion defect.

29. Exercise stress test…. 27-Jul-22 PFT & Its lab studies 29 Technique : check O2 saturation at rest, 4 min and 6 min walk. Walking oxygen desaturation: - Diffusion defect and -V/Q mismatch Criteria for Oxygen Supplementation (Home Oxygen): 1 . PO2 <55 or oxygen saturation <88% 2 . PO2 <59 with pulmonary hypertension

30. General direction for LFT To ensure breathing is normal and unrestricted Patient preparation and education on:- Don't eat a heavy meal before the test. Avoid food or drinks with caffeine. Don't smoke or do heavy exercise for 6hr before the test Wear loose, comfortable clothing . 27-Jul-22 PFT & Its lab studies 30

31. 2. Lab studies (respiratory ) Sputum test Thoracentesis ABG analysis 27-Jul-22 PFT & Its lab studies 31

32. Sputum test A sputum test, also known as a sputum culture . I s a test that may order when you have a RTI or other lung-related disorder to determine what is growing in the lungs . Sputum is a thick substance that accumulates when bacteria or fungi grows and multiples in the lungs or bronchi. As it accumulates, the growing substance can make breathing more difficult and cause coughing 27-Jul-22 PFT & Its lab studies 32

33. SPUTUM TEST CON’T… A sputum test can diagnose: Bronchitis Lung abscess Pneumonia Tuberculosis COPD Cystic fibrosis 27-Jul-22 PFT & Its lab studies 33

34. SPUTUM TEST CON’T… Person having any of the following symptoms, you may need a sputum test: Cough Fever Chills Fatigue Muscle aches Breathing problems Chest pain Confusion 27-Jul-22 PFT & Its lab studies 34

35. What to expect during a sputum test ? During a sputum test, you will be asked to cough deeply enough to bring up a large quantity of sputum so your can evaluate it. The most challenging part of the test is to produce a sample size large enough for it to be tested. Saliva that lives in the upper airways is not useful for this test . 27-Jul-22 PFT & Its lab studies 35

36. E valuate the color of the sample. Off-white , yellow or green sputum can indicate you have pneumonia or bronchitis Red or rusty can indicate you have a more serious condition that needs more testing Grey or black can indicate that you are a smoker or someone who works in a sooty place (like a coal mine) 27-Jul-22 PFT & Its lab studies 36

37. How much sputum is normal? The normal lung produces approximately 20 – 30 ml of mucus per day to assist with the functioning of the muco-ciliary escalator. Mucus is called sputum when an excess amount is produced within the airways and needs to be expectorated. 27-Jul-22 PFT & Its lab studies 37

38. SPUTUM TEST CON’T…………… Sputum from your lungs is usually thick and sticky. Saliva comes from your mouth and is watery and thin. Do not collect saliva Keep doing this until the sputum reaches the 5 ml line or more on the plastic cup. Take a very deep breath and hold the air for 5 seconds. Slowly breathe out. Write on the cup the date you collected the sputum. 27-Jul-22 PFT & Its lab studies 38

39. Results from a sputum test Patient sputum sample will be sent to a laboratory within 1-2hrs of production. A pathologist will run tests to determine if the growth is a bacterium, virus or fungus. Pathologist will send a report to your doctor as soon as possible. Typically, within a few days. Rapid TB tests can be ready in as little as 24 hours, but results for other lung diseases can take as long as eight weeks. 27-Jul-22 PFT & Its lab studies 39

40. What is the role of nurse in sputum test? 27-Jul-22 PFT & Its lab studies 40 Health education about sputum dispose How to coughing and sneezing About breathing exercise Using PPE while patient serving Family’s counseling about TB,Corona and etc. Isolation and quarantine until underlying cause is identified

41. ii. Thoracentesis Thoracentesis is a invasive procedure that is performed to remove fluid from around the lung. The lung is covered with a tissue called the pleura. The inside of the chest is also lined with pleura. The space between these two areas is called the pleural space. This space normally contains just a thin layer of fluid(15-20 ml) H owever, some conditions such as pneumonia, cancer , CHF, liver failure and respiratory infection may cause excessive fluid to develop (pleural effusion) 27-Jul-22 PFT & Its lab studies 41

42. Site and position of needle insertion 27-Jul-22 PFT & Its lab studies 42

43. Thoracentesis………… To remove this fluid for evaluation (testing) or improve a patient’s breathing, a procedure called a thoracentesis Thoracentesis involves placing a thin needle or tube into the pleural space to remove some of the fluid. The needle or tube is inserted through the skin, between the ribs and into the chest. The needle or tube is removed when the procedure is completed . 27-Jul-22 PFT & Its lab studies 43

44. Thoracentesis………… If a person needs more fluid drained, sometimes the tube is left in place for a longer time The procedure takes about 30 minutes but expect your visit to last 1-2 hours to include preparation, and observation in recovery . The fluid is then sent to a laboratory for pleural fluid analysis. 27-Jul-22 PFT & Its lab studies 44

45. Thoracentesis………… The American Thoracic Society says that the most common reasons to perform thoracentesis are: To diagnose the cause of new pleural effusion To improve comfort To diagnose cancer or improve cancer symptoms To diagnose a suspected infection 27-Jul-22 PFT & Its lab studies 45

46. What are the Risks of a Thoracentesis ? P ain during placement Bleeding Collapsed lung Bruise 27-Jul-22 PFT & Its lab studies 46

47. Preparation for a Thoracentesis I nstructions about need to prepare for the procedure;- N ot taking medications prior to or the day of the procedure T o hold eating or drinking for some time period before it. Position :- sitting in a chair or lying on a table U se an ultrasound to confirm the correct area where the needle will go. They may also use CT guidance . Usually an adult or older child remains awake when a thoracentesis is done . The skin is cleaned with a disinfectant before the needle is inserted. 27-Jul-22 PFT & Its lab studies 47

48. Preparation for a Thoracentesis….. Local numbing medicine is injected into the skin first. The fluid may drain through the needle by doctor. When the fluid is removed, the needle and tube are removed and a bandage is placed over the insertion site wound. The wound closes on its own without the need for stitches . Perform a follow-up X-ray right after the thoracentesis. 27-Jul-22 PFT & Its lab studies 48

49. Rx Action Steps Call your healthcare provider if you have: Bleeding from the needle site New , sudden difficulty breathing Pain taking a deep breath A cough that produces blood 27-Jul-22 PFT & Its lab studies 49

50. Rx Action Steps…. After thoracentesis, a lab test called a pleural fluid analysis may be performed to figure out the cause of fluid accumulation around one or both of your lungs. 27-Jul-22 PFT & Its lab studies 50

51. Understanding the results The lab classifies your fluid buildup as either exudate or transudate. Exudate is cloudy in appearance, and it normally contains high levels of protein and a compound known as lactate dehydrogenase (LDH ). It’s most commonly the result of inflammation caused by an infection of the lungs, such as pneumonia or TB. An exudate can also be related to cancer. 27-Jul-22 PFT & Its lab studies 51

52. Understanding the results…. Transudate is a clear fluid that contains little or no protein and low levels of LDH. It usually signifies the failure of an organ such as the liver or heart. If the pleural fluid analysis suggests cancer , further tests including a closer evaluation of the lungs and other organs. Your treatment will depend on the underlying cause of the pleural effusion. 27-Jul-22 PFT & Its lab studies 52

53. C. ABG ( Arterial blood gas) analysis A vital role in monitoring of Postoperative patients, Patients receiving oxygen therapy, Those on intensive support, Patients with significant blood loss, sepsis, and comorbid conditions like diabetes, kidney disorders, Cardiovascular system (CVS) conditions 27-Jul-22 PFT & Its lab studies 53

54. Why do we order a blood gas analysis ? Aids in establishing diagnosis Guides treatment plan Improvement in the management of acid/base Acid/base status may alter levels of electrolytes critical to the status of a patient Effectiveness of gas exchange 27-Jul-22 PFT & Its lab studies 54

55. Limitations of blood gas analysis Can not yield a specific diagnosis. E .g . A patient with asthma may have similar values to another patient with pneumonia Does not reflect the degree to which an abnormality actually affects a patient. Cannot be used as a screening test for early pulmonary disease. 27-Jul-22 PFT & Its lab studies 55

56. Obtaining an arterial sample Order of preference: Radial > brachial >femoral artery Radial artery is preferred: E ase of palpation and access G ood collateral supply. Collateral supply to the hand : Confirmed by the modified Allen's test 27-Jul-22 PFT & Its lab studies 56

57. Modified Allen's test Ask the patient to make a tight fist. Apply pressure to the wrist: Using the middle and index fingers of both hands Compress the radial and ulnar arteries at the same time While maintaining pressure: Ask the patient to open the hand slowly. Lower the hand and release pressure on the ulnar artery only. 27-Jul-22 PFT & Its lab studies 57

58. Modified Allen's test…. Positive test: The hand flushes pink or returns to normal color within 15seconds Negative test: The hand does not flush pink or return to normal color within 15 seconds Indicating a disruption of blood flow from the ulnar artery to the hand Radial artery should not be used 27-Jul-22 PFT & Its lab studies 58

59. Sampling Arm of the patient Palm up on a flat surface Wrist dorsiflexed at 45 °. Puncture site : Cleaned with alcohol or iodine Allow the alcohol to dry Local anesthetic 27-Jul-22 PFT & Its lab studies 59

60. Sampling…….. Radial artery should be palpated for a pulse S yringe with a 23/25 gauge needle should be inserted at an angle just distal to the palpated pulse. After the puncture, sterile gauze should be placed firmly over the site and direct pressure applied for several minutes to obtain hemostasis 27-Jul-22 PFT & Its lab studies 60

61. Errors Always note the percentage of inspired air (FiO2 ) Avoid air bubbles in syringe. Avoid delay in sample processing. Accidental venous sampling. Do not use excess heparin as I t causes sample dilution Excess of heparin may affect the pH 27-Jul-22 PFT & Its lab studies 61

62. The 6 easy s teps to ABG Analysis Is the PH normal? is the O2 is normal? Is the CO3 is normal? Match the CO2 or the HCO3 with the PH? Does the CO2 or the HCO3 go to opposite direction of PH? Are the PO2 or the O2 is normal? 27-Jul-22 PFT & Its lab studies 62

63. Normal & abnormal values of ABG analysis 27-Jul-22 PFT & Its lab studies 63

64. Acid-base in balance 27-Jul-22 PFT & Its lab studies 64

65. Steps of interpretation Step 1: Anticipate the disorder keeping in mind the clinical settings and the condition of the patient E.g ., the patient may present with a history of insulin-dependent diabetes mellitus (IDDM), which may contribute to a metabolic acidosis 27-Jul-22 PFT & Its lab studies 65

66. Step 2: Check the pH pH < 7.35: Acidosis pH > 7.45: Alkalosis pH = 7.35-7.45: Normal/mixed disorder/fully compensated disorder Note : If mixed disorder , pH indicates stronger component If PH is < 6.8 or > 8.0 death occurs. 27-Jul-22 PFT & Its lab studies 66

67. Clues to a mixed disorder : Normal pH with abnormal HCO3 or pCO2 pCO2 and HCO3 move in opposite directions pH changes in an opposite direction for a known primary disorder 27-Jul-22 PFT & Its lab studies 67

68. Step 3: Check SaO2 / paO2 SaO2 is a more reliable indicator as it depicts the saturation of hemoglobin in arterial blood . 27-Jul-22 PFT & Its lab studies 68

69. Step 4: Check CO2 and HCO3(bicarbonate ) levels Identify the culprit Is it a respiratory/metabolic/mixed disorder? 27-Jul-22 PFT & Its lab studies 69

70. Step 5: Check base excess (BE ). Defined as amount of base required to return the pH to a normal range. If it is positive, the metabolic picture is alkalosis . If it is negative, the metabolic picture is acidosis . Either of bicarbonate ions/base excess can be used to interpret metabolic acidosis/alkalosis . Normal BE in blood is -2 to + 2 mmol/L. 27-Jul-22 PFT & Its lab studies 70

71. Step 6: Check for compensation. Is there a compensatory response with respect to the primary change? If yes: compensated If no : Uncompensated . In case of compensation, does it bring the pH to a normal range? If yes: fully compensated If no: Partially compensated 27-Jul-22 PFT & Its lab studies 71

72. Summary of acid base 27-Jul-22 PFT & Its lab studies 72

73. Exercise (Example : 1) If pH is 7.21, HCO3- is 14, and CO2 is 40. Interpretation CO2 is normal HCO3- is decreased A case of metabolic acidosis. Expected compensation would be a decrease in CO2 causing respiratory alkalosis. Now consider this table --- 27-Jul-22 PFT & Its lab studies 73

74. Example-2 P H : 7.55 , paCO2 : 49.0 , HCO3 : 48.2 Interpretation PH : 7.55 ( alkalosis and increased ) P aCO2 : 49.0 (increased) HCO3 : 48.2 (increased) paCO2 is increased - retention of CO2 causes acidosis HCO3 is increased - increased base causes alkalosis So , the primary disorder is metabolic alkalosis . 27-Jul-22 PFT & Its lab studies 74

75. Example -3 A patient is in intensive care because he suffered a severe myocardial infarction 3 days ago. The laboratory reports the following values from an arterial blood sample: What is the possible diagnosis of this patient? PH = 7.3 HCO3- = 20 mEq / L ( 22 - 26) PCO2 = 32 mm Hg (35 - 45) Metabolic acidosis 27-Jul-22 PFT & Its lab studies 75

76. Examples 4 ………… 27-Jul-22 PFT & Its lab studies 76 Chaltu is a 45-year-old female admitted to the nursing unit with a severe asthma attack. She has been experiencing increasing shortness of breath since admission three hours ago. Clinical Laboratory: PH = 7.22 PaCO2 = 55 HCO3 = 25 Respiratory acidosis .

77. … Treat the patient not the ABG!!! Thank you 27-Jul-22 PFT & Its lab studies 77