This document provides an overview of arterial blood gas (ABG) interpretation. It defines key terms like pH, acidosis, alkalosis and discusses the body's buffering systems. The document outlines the steps to interpret an ABG, including identifying the acid-base disorder, looking for compensations, and calculating the anion gap. It also covers techniques for proper blood sampling and discusses factors that can affect ABG results like air bubbles or excess heparin in the syringe.
This document provides information on arterial blood gas (ABG) analysis for neonates, including indications, sample collection and processing, components analyzed, and interpretation. Key points discussed include:
1) ABG analysis is an important tool for assessing cardio-respiratory status in neonates and interpreting diagnosis, treatment, and prognosis.
2) Indications for ABG analysis include respiratory or metabolic disorders, signs of hypoxia or hypercarbia, shock, sepsis, and decreased cardiac output.
3) Components analyzed in an ABG include pH, pCO2, HCO3, pO2, oxygen saturation, and electrolytes. Precise collection and rapid processing are important for accurate results.
This document provides information about arterial blood gas (ABG) analysis. It defines an ABG as a blood sample drawn from an artery to assess acid-base balance, oxygenation, and ventilation. ABGs are ordered to diagnose and monitor respiratory failure and changes in acid-base homeostasis. The components of an ABG include pH, PaCO2, PaO2, HCO3, O2 saturation, and base excess. Normal values for these components are provided. The document discusses how to properly collect an ABG sample and handle it to avoid inaccurate results. It also covers acid-base physiology and the four primary acid-base disorders: metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alk
Arterial Blood Gas (ABG)Procedure and Interpretation \Mohammad Al-me`ani. ,...almaani
Arterial Blood Gas (ABG)Procedure and Interpretation
Understand ABG and its terms.
Know some of the indication and contraindications for performing an arterial puncture.
Be able to demonstrate the technique for performing an arterial puncture.
Understand the interpretation of ABG.
An arterial blood gas (ABG) analysis measures pH, oxygen, and carbon dioxide levels in arterial blood. It is used to assess respiratory and metabolic function. The document outlines how to perform an ABG, including using a syringe to draw blood from the radial, brachial, or femoral artery. It discusses components measured in an ABG and their normal ranges, as well as factors that can affect results. Common acid-base imbalances like respiratory acidosis and metabolic alkalosis are also summarized, along with their primary and compensatory responses.
This document provides information about arterial blood gas (ABG) analysis, including:
1. An ABG test measures pH, partial pressures of oxygen and carbon dioxide, bicarbonate, and base excess from an arterial blood sample. It is used to diagnose and manage oxygenation, ventilation, and acid-base balance issues.
2. The pH, PCO2, HCO3, and other values are involved in acid-base balance and are affected by respiratory and renal buffer systems. Respiratory acidosis, alkalosis, and other acid-base disorders have distinct causes, signs, and management approaches.
3. Interpreting an ABG involves following steps to determine if the primary disturbance
An arterial-blood gas test measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe and a thin needle, but sometimes the femoral artery in the groin or another site is used.
The common indications for ABGs are:
Respiratory compromise, which leads to hypoxia or diminished ventilation.
Peri- or postcardiopulmonary arrest or collapse.
Medical conditions that cause significant metabolic derangement, such as sepsis, diabetic ketoacidosis, renal failure, heart failure, toxic substance ingestion, drug overdose, trauma, or burns.
Evaluating the effectiveness of therapies, monitoring the patient's clinical status, and determining treatment needs. For instance, clinicians often titrate oxygenation therapy, adjust the level of ventilator support, and make decisions about fluid and electrolyte therapy based on ABG results.
During the perioperative phase of major surgeries, which includes the preoperative, intraoperative, and postoperative care of the patient.
The components of an ABG analysis are PaO2, SaO2, hydrogen ion concentration (pH), PaCO2, HCO3-, base excess, and serum levels of hemoglobin, lactate, glucose, and electrolytes (sodium, potassium, calcium, and chloride).
This document provides information on interpreting arterial blood gas results to diagnose acid-base disorders. It discusses the four primary acid-base disorders: respiratory acidosis, metabolic acidosis, respiratory alkalosis, and metabolic alkalosis. Compensatory changes in response to these disorders are explained. The mechanisms by which the body controls acid-base balance through buffers, kidneys, and lungs are outlined. A stepwise approach to interpreting ABG results is provided to determine if there is acidemia/alkalemia, the primary disturbance, compensation, and high anion gap. Causes and characteristics of different acid-base disorders are described.
1. Acid-base disorders are caused by either respiratory or metabolic mechanisms that decrease or increase pH through changes in PCO2 or HCO3 concentrations.
2. Respiratory acidosis occurs when increased PCO2 decreases pH, while respiratory alkalosis is caused by decreased PCO2 and higher pH.
3. Metabolic acidosis results from low extracellular HCO3 levels decreasing pH, and metabolic alkalosis occurs when high HCO3 increases pH.
4. The kidneys work to correct acid-base imbalances by secreting or reabsorbing H+ and HCO3 ions to partially counteract the primary disorder.
This document provides information on arterial blood gas (ABG) analysis for neonates, including indications, sample collection and processing, components analyzed, and interpretation. Key points discussed include:
1) ABG analysis is an important tool for assessing cardio-respiratory status in neonates and interpreting diagnosis, treatment, and prognosis.
2) Indications for ABG analysis include respiratory or metabolic disorders, signs of hypoxia or hypercarbia, shock, sepsis, and decreased cardiac output.
3) Components analyzed in an ABG include pH, pCO2, HCO3, pO2, oxygen saturation, and electrolytes. Precise collection and rapid processing are important for accurate results.
This document provides information about arterial blood gas (ABG) analysis. It defines an ABG as a blood sample drawn from an artery to assess acid-base balance, oxygenation, and ventilation. ABGs are ordered to diagnose and monitor respiratory failure and changes in acid-base homeostasis. The components of an ABG include pH, PaCO2, PaO2, HCO3, O2 saturation, and base excess. Normal values for these components are provided. The document discusses how to properly collect an ABG sample and handle it to avoid inaccurate results. It also covers acid-base physiology and the four primary acid-base disorders: metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alk
Arterial Blood Gas (ABG)Procedure and Interpretation \Mohammad Al-me`ani. ,...almaani
Arterial Blood Gas (ABG)Procedure and Interpretation
Understand ABG and its terms.
Know some of the indication and contraindications for performing an arterial puncture.
Be able to demonstrate the technique for performing an arterial puncture.
Understand the interpretation of ABG.
An arterial blood gas (ABG) analysis measures pH, oxygen, and carbon dioxide levels in arterial blood. It is used to assess respiratory and metabolic function. The document outlines how to perform an ABG, including using a syringe to draw blood from the radial, brachial, or femoral artery. It discusses components measured in an ABG and their normal ranges, as well as factors that can affect results. Common acid-base imbalances like respiratory acidosis and metabolic alkalosis are also summarized, along with their primary and compensatory responses.
This document provides information about arterial blood gas (ABG) analysis, including:
1. An ABG test measures pH, partial pressures of oxygen and carbon dioxide, bicarbonate, and base excess from an arterial blood sample. It is used to diagnose and manage oxygenation, ventilation, and acid-base balance issues.
2. The pH, PCO2, HCO3, and other values are involved in acid-base balance and are affected by respiratory and renal buffer systems. Respiratory acidosis, alkalosis, and other acid-base disorders have distinct causes, signs, and management approaches.
3. Interpreting an ABG involves following steps to determine if the primary disturbance
An arterial-blood gas test measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe and a thin needle, but sometimes the femoral artery in the groin or another site is used.
The common indications for ABGs are:
Respiratory compromise, which leads to hypoxia or diminished ventilation.
Peri- or postcardiopulmonary arrest or collapse.
Medical conditions that cause significant metabolic derangement, such as sepsis, diabetic ketoacidosis, renal failure, heart failure, toxic substance ingestion, drug overdose, trauma, or burns.
Evaluating the effectiveness of therapies, monitoring the patient's clinical status, and determining treatment needs. For instance, clinicians often titrate oxygenation therapy, adjust the level of ventilator support, and make decisions about fluid and electrolyte therapy based on ABG results.
During the perioperative phase of major surgeries, which includes the preoperative, intraoperative, and postoperative care of the patient.
The components of an ABG analysis are PaO2, SaO2, hydrogen ion concentration (pH), PaCO2, HCO3-, base excess, and serum levels of hemoglobin, lactate, glucose, and electrolytes (sodium, potassium, calcium, and chloride).
This document provides information on interpreting arterial blood gas results to diagnose acid-base disorders. It discusses the four primary acid-base disorders: respiratory acidosis, metabolic acidosis, respiratory alkalosis, and metabolic alkalosis. Compensatory changes in response to these disorders are explained. The mechanisms by which the body controls acid-base balance through buffers, kidneys, and lungs are outlined. A stepwise approach to interpreting ABG results is provided to determine if there is acidemia/alkalemia, the primary disturbance, compensation, and high anion gap. Causes and characteristics of different acid-base disorders are described.
1. Acid-base disorders are caused by either respiratory or metabolic mechanisms that decrease or increase pH through changes in PCO2 or HCO3 concentrations.
2. Respiratory acidosis occurs when increased PCO2 decreases pH, while respiratory alkalosis is caused by decreased PCO2 and higher pH.
3. Metabolic acidosis results from low extracellular HCO3 levels decreasing pH, and metabolic alkalosis occurs when high HCO3 increases pH.
4. The kidneys work to correct acid-base imbalances by secreting or reabsorbing H+ and HCO3 ions to partially counteract the primary disorder.
This document provides information about arterial blood gas (ABG) analysis for nursing education. It begins with an introduction on the importance of ABG analysis for diagnosing acid-base balance and oxygenation status. It then covers topics like the basic definitions of acid and base, the buffer system, mechanisms of acid-base regulation, types of acid-base disorders, arterial blood gas components, procedures for ABG sample collection and interpretation, and the nurse's role in ABG analysis. Examples are provided to demonstrate how to interpret ABG results and assess a patient's oxygenation and ventilation status.
1) Arterial blood gas analysis measures gases in arterial blood and helps diagnose acid-base disorders.
2) It involves puncturing an artery with a needle to draw a small volume of blood, which is then analyzed to determine pH, oxygen and carbon dioxide levels.
3) This provides information about a patient's acid-base and respiratory status, and can help monitor conditions and treatment effectiveness.
This document provides an outline for a seminar on arterial blood gas analysis (ABG). The seminar will include an introduction to ABGs, indications for ordering ABGs, the procedure for arterial blood sampling, pulmonary gas exchange, acid-base disorders, and how to approach analyzing an ABG. Resident doctors from pediatrics and cardiology will present on these topics and discuss ABGs versus venous blood gases.
This document discusses acid-base disorders and interpretation of arterial blood gases (ABGs) and spirometry. It provides:
1. An overview of acid-base homeostasis and the three major methods to quantify acid-base disorders - the physiological approach, base-excess approach, and physicochemical approach.
2. The normal ranges for parameters in an ABG report like pH, PaCO2, PaO2, HCO3, and SaO2.
3. A step-wise approach to solving acid-base disorders, including assessing validity, determining if there is acidemia or alkalemia, identifying the primary disorder, assessing compensation, calculating anion gap, and calculating delta gap to
1. The document discusses acid-base balance and interpretation of arterial blood gases (ABGs). It covers definitions of pH, PCO2, and PO2 and their normal ranges.
2. Procedures for obtaining ABGs are outlined along with potential errors and complications.
3. A stepwise approach is provided for interpreting ABGs, identifying respiratory or metabolic acidosis or alkalosis and their underlying causes. Compensatory mechanisms are also addressed.
This document discusses arterial blood gas analysis, including the physiology of oxygenation and factors that influence hemoglobin's affinity for oxygen. It provides reference ranges for blood gas values and guidelines for interpreting results. Techniques for obtaining blood samples and potential complications are outlined. Blood gas analyzers and quality assurance procedures are also reviewed.
The document provides information on arterial blood gas (ABG) sampling and interpretation. It discusses:
- The ideal sites for ABG sampling are the radial, brachial, and femoral arteries. Syringes should be pre-heparinized and air bubbles avoided.
- ABG values like pH, pCO2, pO2, HCO3 help assess a patient's ventilation, oxygenation, and acid-base status. Normal and abnormal ranges are provided.
- Respiratory and metabolic acid-base disturbances can be identified by looking at whether pH, pCO2, and HCO3 are normal or abnormal and if they correlate. Compensation patterns are explained.
An arterial blood gas test involves puncturing an artery, usually the radial artery, to draw blood and measure acidity, oxygen and carbon dioxide levels. It can help diagnose conditions, guide treatment, and monitor ventilator management. The test measures pH, pO2, pCO2, HCO3, SaO2 and base excess. Abnormal results can indicate respiratory or metabolic acidosis or alkalosis which have distinct causes, signs, and treatments. Interpreting blood gases involves assessing oxygenation, acid-base status, and whether the disturbance is primarily respiratory or metabolic in nature.
This document provides information about arterial blood gas (ABG) testing, including how to perform the test, interpret results, and assess acid-base balance and respiratory function. ABG testing measures pH, partial pressures of oxygen and carbon dioxide, and bicarbonate levels in arterial blood to help diagnose conditions affecting ventilation, oxygenation, and acid-base balance. The radial artery is most commonly used for sampling. Results are analyzed to determine if a patient has hypoxemia, respiratory acidosis or alkalosis, or a metabolic imbalance. Compensation by the respiratory or renal systems in response to acid-base disturbances is also assessed.
1. The document provides normal values for arterial blood gases and discusses the interpretation and significance of various blood gas measurements. It covers topics like respiratory and metabolic acidosis/alkalosis, oxygen content, carbon monoxide poisoning, and ventilation/perfusion imbalance.
2. Causes, treatments, and compensatory mechanisms for different acid-base imbalances are explained. Various equations used in blood gas analysis are also presented, such as the Henderson-Hasselbalch and alveolar gas equations.
3. The role of the kidneys, lungs, and hemoglobin in maintaining acid-base balance is described. Factors that can cause hypoxemia and how to determine oxygen adequacy from blood gases are discussed.
An arterial blood gas test measures pH, oxygen, and carbon dioxide levels in blood from an artery. It provides information about oxygenation, ventilation, and acid-base levels. ABGs are useful for evaluating respiratory failure, severe illnesses that can cause metabolic acidosis like cardiac or liver failure, and conditions in ventilated patients or those undergoing sleep studies. Interpretation of ABG results involves considering pH, carbon dioxide, bicarbonate, and oxygen levels to determine if any acid-base imbalances exist and their underlying cause.
The document discusses acid-base imbalance and provides definitions and normal ranges for various related terms and measurements. It covers the body's mechanisms for regulating pH and describes different types of acid-base disorders and mixed disorders. Arterial blood gas analysis is an important tool for assessing acid-base status and pulmonary function.
The document discusses techniques for arterial blood gas (ABG) sampling and interpretation of ABG results. It covers topics like Allen's test to check collateral circulation before radial or ulnar artery puncture, nursing responsibilities for arterial lines, how to obtain ABG samples from lines, and interpretation of pH, PaO2, PaCO2, and HCO3 levels to determine if acidosis or alkalosis is present and whether it is respiratory or metabolic in nature. Compensatory mechanisms, clinical presentations, and nursing priorities for different acid-base imbalances are also outlined.
The normal ranges for arterial blood gas values
Approach to arterial blood gas interpretation
Arterial blood gas abnormalities in special circumstances
Here are the key steps to analyze this mixed acid-base case:
1. Identify the primary disturbances:
- Respiratory alkalosis due to hyperventilation (PaCO2 28-30)
- Metabolic acidosis likely due to lasix use (daily high dose diuretic)
2. Determine the compensatory responses:
- Respiratory compensation for metabolic acidosis (lower than normal PaCO2)
- Renal compensation not yet fully compensated the metabolic acidosis
3. Analyze the ABG values in the context of the primary disturbances and degree of compensation.
- The ABG values reflect both an ongoing metabolic acidosis and respiratory alkalosis.
4.
This document provides an overview of arterial blood gases (ABGs), including:
- What ABGs measure (oxygenation levels, acid-base disturbances, pH, pO2, pCO2, and other electrolytes)
- When ABGs are indicated (respiratory monitoring, unstable patients, post cardiac arrest, intra-operatively)
- How the body maintains acid-base balance through respiratory, renal, and chemical buffers that keep pH between 7.35-7.45.
- Common acid-base disturbances include respiratory or metabolic acidosis/alkalosis caused by changes in pCO2, bicarbonate, or other factors. Interpreting ABG values can help
This document provides an overview of arterial blood gas analysis. It discusses the physiology of acid-base status including the basics of pH, acids, bases and buffers. The key buffers that help regulate acid-base balance are the bicarbonate buffer system and protein buffers. Respiratory regulation is also important as carbon dioxide production is a major factor influencing hydrogen ion concentration and pH. The kidneys play an important role in excretion of acids and bases to help maintain homeostasis.
Here are the key points about assessing ventilation from an ABG:
- PaCO2 is used to assess ventilation. The normal range is 35-45 mmHg.
- A PaCO2 higher than 45 mmHg indicates respiratory acidosis from hypoventilation or obstruction.
- A PaCO2 lower than 35 mmHg indicates respiratory alkalosis from hyperventilation.
- The pH and HCO3- will be affected by changes in PaCO2 based on the type of respiratory problem (acidosis vs alkalosis). They move in opposite directions for respiratory issues.
- Compensation by the kidneys will cause the HCO3- to rise or fall in the same direction as PaCO
This document provides an overview of arterial blood gas (ABG) analysis, including how to interpret an ABG test result. It discusses how an ABG measures oxygen, carbon dioxide, acidity levels and other values in arterial blood. The document outlines the technique for arterial blood sampling, including common sites and proper technique. It also discusses specimen care and transport. Finally, it provides guidance on how to interpret ABG results, including how to assess oxygenation/hypoxemia, acid-base disorders, and the compensatory responses of the body. Key areas like normal values, mechanisms of acid-base imbalances, and the steps to analyze an ABG result are summarized.
Diagnosis and treatment of acid base disorders(1)aparna jayara
This document discusses the diagnosis and treatment of acid-base disorders. It begins by explaining the importance of precise pH regulation between 7.35-7.45 for cellular functions. Buffers help control free hydrogen ion concentration. Respiratory regulation controls PaCO2 through lung excretion of volatile acids, while renal regulation maintains plasma HCO3- concentration through kidney processes. Primary acid-base disorders are either metabolic, affecting HCO3-, or respiratory, affecting PaCO2. Expected compensatory responses occur but do not fully correct the primary disorder. Evaluation involves history, exam, basic labs, and arterial blood gas analysis to determine the primary disorder and characterize as acute or chronic.
PRESENT: Acid base balance hossam (1).pptMbabazi Theos
This document discusses acid-base balance and interpreting arterial blood gas results. It begins by outlining the objectives of understanding acid-base physiology and the roles of pH, PaCO2, and bicarbonate. Normal values for arterial blood gases are defined. Causes, signs, and treatments of respiratory acidosis, respiratory alkalosis, metabolic acidosis, and metabolic alkalosis are reviewed. The document explains how to interpret an arterial blood gas report using a multi-step process of analyzing pH, PaCO2, and bicarbonate levels to determine if an acid-base imbalance is respiratory or metabolically-driven. Two case examples are provided and interpreted using the outlined steps.
This document provides information about arterial blood gas (ABG) analysis for nursing education. It begins with an introduction on the importance of ABG analysis for diagnosing acid-base balance and oxygenation status. It then covers topics like the basic definitions of acid and base, the buffer system, mechanisms of acid-base regulation, types of acid-base disorders, arterial blood gas components, procedures for ABG sample collection and interpretation, and the nurse's role in ABG analysis. Examples are provided to demonstrate how to interpret ABG results and assess a patient's oxygenation and ventilation status.
1) Arterial blood gas analysis measures gases in arterial blood and helps diagnose acid-base disorders.
2) It involves puncturing an artery with a needle to draw a small volume of blood, which is then analyzed to determine pH, oxygen and carbon dioxide levels.
3) This provides information about a patient's acid-base and respiratory status, and can help monitor conditions and treatment effectiveness.
This document provides an outline for a seminar on arterial blood gas analysis (ABG). The seminar will include an introduction to ABGs, indications for ordering ABGs, the procedure for arterial blood sampling, pulmonary gas exchange, acid-base disorders, and how to approach analyzing an ABG. Resident doctors from pediatrics and cardiology will present on these topics and discuss ABGs versus venous blood gases.
This document discusses acid-base disorders and interpretation of arterial blood gases (ABGs) and spirometry. It provides:
1. An overview of acid-base homeostasis and the three major methods to quantify acid-base disorders - the physiological approach, base-excess approach, and physicochemical approach.
2. The normal ranges for parameters in an ABG report like pH, PaCO2, PaO2, HCO3, and SaO2.
3. A step-wise approach to solving acid-base disorders, including assessing validity, determining if there is acidemia or alkalemia, identifying the primary disorder, assessing compensation, calculating anion gap, and calculating delta gap to
1. The document discusses acid-base balance and interpretation of arterial blood gases (ABGs). It covers definitions of pH, PCO2, and PO2 and their normal ranges.
2. Procedures for obtaining ABGs are outlined along with potential errors and complications.
3. A stepwise approach is provided for interpreting ABGs, identifying respiratory or metabolic acidosis or alkalosis and their underlying causes. Compensatory mechanisms are also addressed.
This document discusses arterial blood gas analysis, including the physiology of oxygenation and factors that influence hemoglobin's affinity for oxygen. It provides reference ranges for blood gas values and guidelines for interpreting results. Techniques for obtaining blood samples and potential complications are outlined. Blood gas analyzers and quality assurance procedures are also reviewed.
The document provides information on arterial blood gas (ABG) sampling and interpretation. It discusses:
- The ideal sites for ABG sampling are the radial, brachial, and femoral arteries. Syringes should be pre-heparinized and air bubbles avoided.
- ABG values like pH, pCO2, pO2, HCO3 help assess a patient's ventilation, oxygenation, and acid-base status. Normal and abnormal ranges are provided.
- Respiratory and metabolic acid-base disturbances can be identified by looking at whether pH, pCO2, and HCO3 are normal or abnormal and if they correlate. Compensation patterns are explained.
An arterial blood gas test involves puncturing an artery, usually the radial artery, to draw blood and measure acidity, oxygen and carbon dioxide levels. It can help diagnose conditions, guide treatment, and monitor ventilator management. The test measures pH, pO2, pCO2, HCO3, SaO2 and base excess. Abnormal results can indicate respiratory or metabolic acidosis or alkalosis which have distinct causes, signs, and treatments. Interpreting blood gases involves assessing oxygenation, acid-base status, and whether the disturbance is primarily respiratory or metabolic in nature.
This document provides information about arterial blood gas (ABG) testing, including how to perform the test, interpret results, and assess acid-base balance and respiratory function. ABG testing measures pH, partial pressures of oxygen and carbon dioxide, and bicarbonate levels in arterial blood to help diagnose conditions affecting ventilation, oxygenation, and acid-base balance. The radial artery is most commonly used for sampling. Results are analyzed to determine if a patient has hypoxemia, respiratory acidosis or alkalosis, or a metabolic imbalance. Compensation by the respiratory or renal systems in response to acid-base disturbances is also assessed.
1. The document provides normal values for arterial blood gases and discusses the interpretation and significance of various blood gas measurements. It covers topics like respiratory and metabolic acidosis/alkalosis, oxygen content, carbon monoxide poisoning, and ventilation/perfusion imbalance.
2. Causes, treatments, and compensatory mechanisms for different acid-base imbalances are explained. Various equations used in blood gas analysis are also presented, such as the Henderson-Hasselbalch and alveolar gas equations.
3. The role of the kidneys, lungs, and hemoglobin in maintaining acid-base balance is described. Factors that can cause hypoxemia and how to determine oxygen adequacy from blood gases are discussed.
An arterial blood gas test measures pH, oxygen, and carbon dioxide levels in blood from an artery. It provides information about oxygenation, ventilation, and acid-base levels. ABGs are useful for evaluating respiratory failure, severe illnesses that can cause metabolic acidosis like cardiac or liver failure, and conditions in ventilated patients or those undergoing sleep studies. Interpretation of ABG results involves considering pH, carbon dioxide, bicarbonate, and oxygen levels to determine if any acid-base imbalances exist and their underlying cause.
The document discusses acid-base imbalance and provides definitions and normal ranges for various related terms and measurements. It covers the body's mechanisms for regulating pH and describes different types of acid-base disorders and mixed disorders. Arterial blood gas analysis is an important tool for assessing acid-base status and pulmonary function.
The document discusses techniques for arterial blood gas (ABG) sampling and interpretation of ABG results. It covers topics like Allen's test to check collateral circulation before radial or ulnar artery puncture, nursing responsibilities for arterial lines, how to obtain ABG samples from lines, and interpretation of pH, PaO2, PaCO2, and HCO3 levels to determine if acidosis or alkalosis is present and whether it is respiratory or metabolic in nature. Compensatory mechanisms, clinical presentations, and nursing priorities for different acid-base imbalances are also outlined.
The normal ranges for arterial blood gas values
Approach to arterial blood gas interpretation
Arterial blood gas abnormalities in special circumstances
Here are the key steps to analyze this mixed acid-base case:
1. Identify the primary disturbances:
- Respiratory alkalosis due to hyperventilation (PaCO2 28-30)
- Metabolic acidosis likely due to lasix use (daily high dose diuretic)
2. Determine the compensatory responses:
- Respiratory compensation for metabolic acidosis (lower than normal PaCO2)
- Renal compensation not yet fully compensated the metabolic acidosis
3. Analyze the ABG values in the context of the primary disturbances and degree of compensation.
- The ABG values reflect both an ongoing metabolic acidosis and respiratory alkalosis.
4.
This document provides an overview of arterial blood gases (ABGs), including:
- What ABGs measure (oxygenation levels, acid-base disturbances, pH, pO2, pCO2, and other electrolytes)
- When ABGs are indicated (respiratory monitoring, unstable patients, post cardiac arrest, intra-operatively)
- How the body maintains acid-base balance through respiratory, renal, and chemical buffers that keep pH between 7.35-7.45.
- Common acid-base disturbances include respiratory or metabolic acidosis/alkalosis caused by changes in pCO2, bicarbonate, or other factors. Interpreting ABG values can help
This document provides an overview of arterial blood gas analysis. It discusses the physiology of acid-base status including the basics of pH, acids, bases and buffers. The key buffers that help regulate acid-base balance are the bicarbonate buffer system and protein buffers. Respiratory regulation is also important as carbon dioxide production is a major factor influencing hydrogen ion concentration and pH. The kidneys play an important role in excretion of acids and bases to help maintain homeostasis.
Here are the key points about assessing ventilation from an ABG:
- PaCO2 is used to assess ventilation. The normal range is 35-45 mmHg.
- A PaCO2 higher than 45 mmHg indicates respiratory acidosis from hypoventilation or obstruction.
- A PaCO2 lower than 35 mmHg indicates respiratory alkalosis from hyperventilation.
- The pH and HCO3- will be affected by changes in PaCO2 based on the type of respiratory problem (acidosis vs alkalosis). They move in opposite directions for respiratory issues.
- Compensation by the kidneys will cause the HCO3- to rise or fall in the same direction as PaCO
This document provides an overview of arterial blood gas (ABG) analysis, including how to interpret an ABG test result. It discusses how an ABG measures oxygen, carbon dioxide, acidity levels and other values in arterial blood. The document outlines the technique for arterial blood sampling, including common sites and proper technique. It also discusses specimen care and transport. Finally, it provides guidance on how to interpret ABG results, including how to assess oxygenation/hypoxemia, acid-base disorders, and the compensatory responses of the body. Key areas like normal values, mechanisms of acid-base imbalances, and the steps to analyze an ABG result are summarized.
Diagnosis and treatment of acid base disorders(1)aparna jayara
This document discusses the diagnosis and treatment of acid-base disorders. It begins by explaining the importance of precise pH regulation between 7.35-7.45 for cellular functions. Buffers help control free hydrogen ion concentration. Respiratory regulation controls PaCO2 through lung excretion of volatile acids, while renal regulation maintains plasma HCO3- concentration through kidney processes. Primary acid-base disorders are either metabolic, affecting HCO3-, or respiratory, affecting PaCO2. Expected compensatory responses occur but do not fully correct the primary disorder. Evaluation involves history, exam, basic labs, and arterial blood gas analysis to determine the primary disorder and characterize as acute or chronic.
PRESENT: Acid base balance hossam (1).pptMbabazi Theos
This document discusses acid-base balance and interpreting arterial blood gas results. It begins by outlining the objectives of understanding acid-base physiology and the roles of pH, PaCO2, and bicarbonate. Normal values for arterial blood gases are defined. Causes, signs, and treatments of respiratory acidosis, respiratory alkalosis, metabolic acidosis, and metabolic alkalosis are reviewed. The document explains how to interpret an arterial blood gas report using a multi-step process of analyzing pH, PaCO2, and bicarbonate levels to determine if an acid-base imbalance is respiratory or metabolically-driven. Two case examples are provided and interpreted using the outlined steps.
Arterial blood gas analysis in clinical practice (2)Mohit Aggarwal
This document provides information about arterial blood gases (ABGs), including what an ABG is, the components that are measured, normal ranges, reasons for ordering an ABG, how to interpret ABG results, and types of acid-base imbalances. An ABG is a blood test that measures pH, oxygen, and carbon dioxide levels to help diagnose respiratory and metabolic conditions. The document outlines the steps to interpret an ABG and explains various acid-base disorders like respiratory acidosis, metabolic alkalosis, and mixed disorders. Compensation mechanisms of the lungs and kidneys in response to acid-base imbalances are also discussed.
The document provides information on interpreting arterial blood gases (ABGs). It discusses:
- How the lungs and kidneys work to maintain acid-base balance by regulating carbon dioxide and bicarbonate levels.
- Key terms like pH, acidosis, alkalosis and how changes in pCO2 and HCO3 impact acid-base status.
- The process for drawing an ABG sample and analyzing the results, including calculating values like oxygen saturation and alveolar-arterial gradient.
- How to assess for primary acid-base disorders by looking at pH, pCO2 and HCO3 levels and whether compensation is appropriate.
- Formulas like Winter's equation and those for calculating
This document provides an overview of the pathophysiology of pH and acid-base homeostasis. It discusses:
1. The definition of pH and normal pH levels in the body. Acids donate hydrogen ions while bases accept them.
2. The two main buffer systems that help regulate pH - the bicarbonate buffer system and protein buffers. The Henderson-Hasselbalch equation describes the relationship between bicarbonate, carbonic acid and pH.
3. The mechanisms that generate and regulate acids and bases in the body, including the roles of respiration, the kidneys, and various buffer systems.
4. The classifications of acid-base disturbances including respiratory and metabolic acidosis/alk
ABG test measures the blood gas tension values of the arterial partial pressure of oxygen, and the arterial partial pressure of carbon dioxide, and the blood's pH
The document discusses acid-base balance and acid-base disorders. It describes three main systems that help maintain pH balance - buffers, the respiratory system, and the renal system. It explains how to interpret arterial blood gases by evaluating the pH, pCO2, HCO3, and other values to determine if a patient has respiratory or metabolic acidosis or alkalosis. Compensation by other systems is discussed when one system is imbalanced. Interpreting values and identifying primary vs compensated disorders is key to proper nursing care.
This presentation discuss about acid-base-gas normal ratio and its indication in relation to varying abnormal level and how to manage it. This includes clinical analysis practice.
Metabolic acidosis is caused by an excess production of acids or loss of bicarbonate in the body. It results in a primary decrease in blood pH (acidemia) with low bicarbonate levels. The kidneys compensate by retaining bicarbonate to raise the pH. Causes include diabetic ketoacidosis, lactic acidosis, renal tubular acidosis, diarrhea, and uremia. An increased anion gap metabolic acidosis occurs when unmeasured anions like ketones and lactate are produced in excess. The clinical features include respiratory changes like Kussmaul breathing, as well as neurological symptoms. Arterial blood gas analysis is used to diagnose and classify the type and
Abg analysis in emergency medicine departmentDrRahulyadav7
This document provides an outline and overview of arterial blood gas (ABG) analysis. It begins with an introduction to the lung and kidney functions related to gas exchange and acid-base balance. It then defines an ABG test and lists common indications. The document outlines the components of an ABG, normal values, procedure steps, complications, and approaches to interpreting results including identifying acid-base disorders and assessing respiratory and renal compensation. It provides detail on sampling sites, transport considerations, and approaches to troubleshooting and solving acid-base disturbances based on ABG parameters.
This document provides information on arterial blood gas analysis including acid-base terminology, clinical terminology criteria, the anion gap, prediction of compensatory changes, primary acid-base disorders, mixed acid-base disorders, examples of acid-base disorders, and causes of various disorders. Key points include definitions of acidemia, acidosis, alkalemia, and alkalosis. Normal values for pH, PaCO2, and HCO3 are provided. Respiratory and metabolic acidosis and alkalosis are described along with expected compensatory changes.
This document provides an overview of arterial blood gas analysis. It discusses how ABG provides information about ventilation, oxygenation, and acid-base balance. The key points covered include indications for ABG, contraindications, sample collection sites and techniques, complications, acid-base physiology including buffer systems and compensation mechanisms, and a stepwise approach to ABG interpretation.
This document provides an overview of acid-base disorders. It discusses the history of acid-base balance, definitions, buffers, and the different types of acid-base disorders including respiratory acidosis, metabolic acidosis, respiratory alkalosis, and metabolic alkalosis. It also covers analyzing arterial blood gases, interpreting values, compensatory responses, and treatment approaches for acid-base imbalances. Case examples are presented to demonstrate interpreting acid-base disorders from blood tests.
This document provides information about arterial blood gas (ABG) analysis, including defining ABG, listing its components and normal values, discussing indications for the test, and interpreting abnormal values. It describes how ABG analysis can be used to evaluate respiratory and acid-base conditions and effectiveness of oxygen therapy. The document also outlines acid-base imbalances like respiratory acidosis and alkalosis and metabolic acidosis and alkalosis, and how the body compensates for these imbalances through respiratory and renal systems.
1. The pH is normal but HCO3 is high and PaCO2 is high, indicating a mixed picture.
2. The high PaCO2 suggests respiratory acidosis as the primary process (from COPD).
3. The high HCO3 indicates metabolic alkalosis as the secondary process (from vomiting losing hydrochloric acid).
3. This patient has a mixed acid-base disorder of respiratory acidosis combined with metabolic alkalosis.
1. The pH is normal but HCO3 is high and PaCO2 is high, indicating a mixed picture.
2. The high PaCO2 suggests respiratory acidosis as the primary process (from COPD).
3. The high HCO3 indicates metabolic alkalosis as the secondary process (from vomiting).
3. This patient has a mixed acid-base disorder of respiratory acidosis combined with metabolic alkalosis.
Arterial blood gas presentation in ICU/OTDrVANDANA17
This document discusses arterial blood gas (ABG) sampling and analysis. Some key points:
- ABG provides important information about respiratory, metabolic and mixed acid-base disorders through measurement of pH, pCO2 and HCO3 levels.
- It can help guide treatment, especially for critically ill patients, as results are rapidly available at the bedside.
- Samples must be taken and analyzed properly to avoid inaccuracies from factors like delayed analysis, air bubbles, excessive heparin or temperature changes.
- ABG interpretation involves classifying the primary acid-base disorder based on directional changes in pH and pCO2, and evaluating any secondary responses. This helps identify conditions like respiratory acid
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
Histololgy of Female Reproductive System.pptxAyeshaZaid1
Dive into an in-depth exploration of the histological structure of female reproductive system with this comprehensive lecture. Presented by Dr. Ayesha Irfan, Assistant Professor of Anatomy, this presentation covers the Gross anatomy and functional histology of the female reproductive organs. Ideal for students, educators, and anyone interested in medical science, this lecture provides clear explanations, detailed diagrams, and valuable insights into female reproductive system. Enhance your knowledge and understanding of this essential aspect of human biology.
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Kat...rightmanforbloodline
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
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2. INTRODUCTION
➤ Arterial blood gas analysis refers to measurement of pH and
partial pressure of oxygen and carbon dioxide in arterial blood.
➤ Chronic, mild derangements in acid–base status may interfere
with normal growth and development, whereas acute, severe
changes in pH can be fatal.
➤ Acid-base homeostasis exerts a major influence on protein
function, thereby critically affecting tissue and organ
performance.
3. TERMINOLOGIES
➤ pH is negative logarithm of h+ ion activity there is inverse
relationship between pH and hydrogen ion concentration
➤ Maintaining a normal pH is necessary because hydrogen ions
are highly reactive and especially likely to combine with
proteins, altering function.
➤ Acidaemia is defined as increase in H+ and decrease in
arterial pH
➤ Acidosis is process that acidifies body fluids , lowers plasma
HCO3 and if unopposed, will lead too fall in pH
➤ Alkalosis is a process than alkalinizes body fluid and if
unopposed lead to rise in pH
4. ➤ Buffers a solution containing a substances that have the
ability to maintain changes in pH when added to it.
➤ 4 major buffers are bicarbonate, plasma protein, hemoglobin,
phosphates.
➤ pKa is negative logarithm of the dissociation constant. If it
describes a buffer system, then it is numerically equal to the
pH of the system when acid and anion are present in equal
concentration.
➤ Base excess is an index of magnitude of the metabolic
contribution to acid base disturbance.
➤ The normal base excess range of +/-2mEq/L
5. ➤ A BE less than -2 signifies the presence of metabolic acidosis,
whereas BE more than +2signifies the presence of metabolic
alkalosis.
6. Under standard conditions
BASE EXCESS
Positive base excess: metabolic
alkalosis
The amount of acid that returns the
pH of blood sample to normal
Negative base excess: metabolic
acidosis
The amount of alkali that returns
the pH of blood sample to normal
7. BUFFERING MECHANISM
➤ Buffers are first line of defense blunting changes in h+
➤ Extracellular buffers are
A buffer pair consists of :
A base {H+ acceptor} & an
acid {H+ donor}
HCO3-
HPO4
Proteins
8. Different buffer systems assume dominant roles
in different parts of the body
Extracelluar fluid
Major buffer
-bicarbonate buffer
system
Minor buffers
-intracellular protein
-phosphate buffer
sytem
Intracellular
fluid
Major buffers
-Proteins
-phosphate
Blood
Major buffers
-bicarbonate
buffer system
-hemoglobin
Minor buffers
-plasma
proteins
-phosphate
Urine
Major buffers
-ammonia
-phosphate
9. Is the carbonic acid system an ideal buffer
system?
Normal blood levels of HCO3 and CO2
HCO3:22-26 mEq/L
CO2 : 40mmHg
i.e.;0.03✕40=1.2mEq/L
(0.03 being the solubility
coefficient of co2)
At the normal body pH of 7.4 the rate of HCO3 : CO2 =24:1.2 =20
An ideal buffer should have a ratio of 1:1.
A HCO3:CO2 ratio of 20:1 would normally make for a poor buffer system if it
were not possible to regulate HCO3 or CO2 concentrations.
10. RESPIRATORY REGULATION
➤ 2nd line of defense
➤ 10-12 mol/day CO2 is accumulated and is transported to
lungs as HB-generated HCO3 and HB-bound carbamino
compounds where it is freely excreted.
➤ accumulation/ loss of co2 changes in pH within minutes
H2O + CO2 = H2CO3
= H+ + HCO3-
11. ➤ Balance affected by neurorespiratory control of ventilation.
➤ During acidosis, chemoreceptors sense decrease in pH and
trigger ventilation decreasing PaCO2.
➤ Response to alkalosis is biphasic. Initial hyperventilation to
remove excess PaCO2 followed by suppression to increase
PaCO2 to return pH to normal
12. RENAL REGULATION
➤ Kidneys are the ultimate defense against the addition of non-
volatile acid/alkali.
➤ Kidneys play a role in the maintenance of HCO3 by
-Conservation of filtered HCO3
-Regeneration of HCO3
➤ Net acid excretion {NAE} :
-Kidney balance nonvolatile acid generation during metabolism
by excreting acid.
-Each mEq of NAE corresponds to 1 mEq of HCO3 returned to
ECF
13. ➤ NAE has three components:
1. NH4+
2. TITRABLE ACIDS
3. BICARBONATE
14. RENAL COMPENSATIONS FOR ACID BASE DISTURBANCES
➤ Glutamine metabolism and NH4+ excretion are increased
during acidosis and decreased during alkalosis, the signal is
unknown
➤ Tubular hydrogen ion secretion is
1. Increased by the increased blood Pco2 of respiratory acidosis
and decreased Pco2 of respiratory alkalosis.
2. Increased independently of changes in Pco2 by the local
effects of decreased extracellular pH on the tubules.
15. INDICATIONS & CONTRAINDICATIONS
➤ Indications :
1. Suspected hypercapnia
2. Suspected severe hypoxemia
3. Severe, prolonged and worsening respiratory distress
4. Any severely unwell patient
5. Acute deterioration of consciousness
6. Mechanically ventilated patients
7. Patients with respiratory failure
8. Candidates for long-term oxygen therapy
9. Inborn errors of metabolism
16. ➤ Contraindications:
1. Inadequate collateral circulation at the puncture site
2. Should not be performed through a lesion or a surgical shunt
3. Evidence of peripheral vascular disease distant to the
puncture site
4. A coagulopathy or medium to high dose anticoagulation
therapy
17. TECHNIQUE OF SAMPLING
➤ Sites of puncture: the site chooses for taking arterial blood depends on
factors such as your own preference and skill, access, and patient
clinical condition.
➤ Ideal artery for sampling in newborn is radial or umbilical artery
➤ If sample from umbilical catheter taken, one should assure free flow of
blood and remove three or four times dead space volume before
sample taken
➤ Allen test is performed to ensure collateral blood supply by ulnar
artery
18.
19.
20. ➤ Equipment required for obtaining an arterial sample
1. Skin preparation fluid alcohol or iodine based
2. Syringe size 2ml containing 0.5% or 1% plain lignocaine with
22G needle attached to it
3. Use 0.25ml heparin of lower strength 1000 units per ml
instead of 5000 units per ml
4. Gauze swabs or cotton wool for applying pressure on
puncture site after sample has been taken
5. Slushed ice for transportation
21.
22. ➤ Precautions for collection
1. Heparin is acidic and lowers pH. Use small volume of heparin
just for lubricating syringe and plunger
2. Avoid air bubble and let syringe fill spontaneously. Sluggish
filling of syringe indicates that you have accidentally entered
vein rather than artery.
3. It is desirable to use glass syringe as plastic syringe are
permeable to air
4. Vigorous rotation of syringe between palms of hands for
about 20 sec ensures thorough mixing of blood with heparin
5. Always note whether an ABG was drawn while the patient
was receiving oxygen therapy
23. THE EFFECT OF AN AIR BUBBLE IN THE SYRINGE
The effect of an air bubble on the arterial blood in a syringe can have a variable
effect on the PaO2, and a predictable effect on the pH and the PaCO2. The gases in
the blood sample and in trapped air bubble will, tend to equilibrate with each other
The PaO2 of ambient air at
sea level is approximately
160mmHg, so this PaO2 of air
bubble trapped within syringe
If the PaO2 of
arterial blood
is
<160mmHg it
will rise
If the PaO2 of
the arterial
blood
>160mmHg it
will fall
CO2 is present in
minuscule levels in
ambient air. In other
words the PaCO2 in
trapped air is
virtually zero
The PaCO2 of the
arterial blood will
trend towards zero.
pH
The effect of trapped air
bubble on the pH is
related to its effect on
PaCO2
At the PaCO2 of the
blood falls due to the
effect of the air bubble,
pH will rise i.e, the blood
becomes alkalemic
24. EFFECT OF THE OVER-HEPARINIZATION OF THE SYRINGE
Heparin is a sulfated mucopolysaccharide with acidic properties. An excess of
heparin in syringe can have following effects:
Effect on pH
If the pH is normal
or alkaline to begin
with:
If the pH is very
acidic to begin
with:
Acidemia increases
pH will fall on
contact with acidic
heparin
Acidemia
decreases
pH will rise as the
mildly acidic
heparin reduces
the greater acidity
of blood
Dilutional effect
The PaO2 and PaCO2 can also
be spuriously lowered by
dilution.
25. pH 7.35-7.45
pCO2 35-45mmHg
pO2 80-100mmHg
O2 saturation 95-100%
HCO3 22-26mEq/L
Base Excess + or - 2
Anion gap 10-15mEq/L
Normal values (at sea level) range:
26. 37deg 4deg
pH 0.01 0.001
pCO2 0.1mm Hg 0.01Hg
pO2 0.1mm Hg 0.01Hg
Changes in ABG every 10minutes in vitro
29. STEP 2: CHECKING THE ACCURACY OF ABG
➤ (H+) = 24 ✕ PaCO2 / HCO3
➤ pH 7.40 = 40 nEq/L (H+)
➤ 0.01 Change in pH within range of 7.20 to 7.50 there is 1nEq/L
inverse change in h+
30. pH (H+) in nm/L
7.00 100
7.10 80
7.20 63
7.30 50
7.40 40
7.50 30
7.60 25
7.70 20
7.80 15
8.00 10
pH is inversely related to (H+). A pH change of
1.00 represents 10 fold change in (H+)
31. STEP 4 : IDENTIFY THE DISORDER
The normal ph is 7.4(7.36-7.45)
Acidosis or alkalosis?
pH<7.36 : acidosis pH>7.44 : alkalosis
What type of acidosis?
If HCO3 low, the
disorder is
metabolic
acidosis
If CO2 is high
the disorder is
respiratory
acidosis
What type of alkalosis?
If the PCO2 low,
the disorder is
respiratory
alkalosis
If the HCO3 is
high, the
disorder is
metabolic
alkalosis
32. TEST NORMAL ↓VALUE ↑ VALUE
pH 7.35-7.45 ACIDOSIS ALKALOSIS
pCO2 35-45 ALKALOSIS ACIDOSIS
HCO3 22-26 ACIDOSIS ALKALOSIS
pO2 80-100 HYPOXEMIA O2 therapy
SaO2 95-100% HYPOXEMIA
Evaluation of abnormal values:
33. pH HCO3 PaCO2
METABOLIC
ACIDOSIS
LOW LOW LOW
METABOLIC
ALKALOSIS
HIGH HIGH HIGH
RESPIRATORY
ALKALOSIS
HIGH LOW LOW
RESPIRATORY
ACIDOSIS
LOW HIGH HIGH
Simple acid base disturbances and pattern of
change
34. ➤ One way to remember this relationship is to use the acronym
ROME
RESPIRATORY OPPOSITE
METABOLIC EQUAL
➤ The CO2 is the respiratory component of the ABG and if it
is low and the pH is high the patient would have a
respiratory alkalosis. They move is opposite direction to
match
➤ The HCO3 is the metabolic component of the ABG. If the
HCO3 is low and the pH is low the patient would have
metabolic acidosis. They move in same direction to match
35. STEP 5 :LOOK FOR COMPENSATION
METABOLIC ACIDOSIS
PaCO2=(1.5✕HCO3)+8 +/- 2
Or
PaCO2 will ↓1.25mmHg per mmol/
L↓ in HCO3
Or
PaCO2=HCO3 + 15
METABOLIC ALKALOSIS
PaCO2 will ↑0.75mmHg per
mmol/L ↑ in HCO3
Or
PaCO2 will ↑6mmHg per 10mmol/L
↑ in HCO3
Or
PaCO2=HCO3+15
36. RESPIRATORY ALKALOSIS
ACUTE: HCO3 will ↓0.2mmol/L
per mmHg ↓ in PaCO2
CHRONIC: HCO3 will ↓ 0.4mmol/L
per mmHg ↓ in PaCO2
RESPIRATORY ACIDOSIS
ACUTE: HCO3 will ↑ 0.1mmol/L
per mmHg ↑ in PaCO2
CHRONIC: HCO3 will ↑ 0.4 mmol/L
per mmHg ↑ in PaCO2
37. RESPIRATORY COMPENSATION IS
ALWAYS FAST …12-24 hrs
METABOLIC COMPENSATION IS ALWAYS
SLOW ….5-7 DAYS
➤ Body’s physiologic response to primary disorder in order to
bring pH towards normal limit
➤ There can be full compensation, partial compensation, no
compensation( uncompensated )
➤ But never overshoot , if overshoot pH is there it is a mixed
disorder
38. STEP 6 :ANION GAP
➤ Anion gap= Na - (Cl + HCO3)
➤ Normal range is 10+/-2 mEq/L
➤ It represents unmeasured anions. These unmeasured anions
can be;
1. Anionic proteins
2. SO4, PO4, Organic anions
3. Acid anions(acetoacetate, lactate, uremic anions)
39. ➤ Anion gap can increase either due to:
1. Increase in the unmeasured anions.
2. Decrease in the unmeasured cations(hypocalcemia,
hypomagnesemia)
➤ Anion gap may decrease due to
A. Increase in unmeasured cations( Ca, Mg, K)
B. Addition of abnormal cations (Li)
C. Decrease in albumin (each 1g/dl decrease of albumin AG by
2.5 mEq/L
40. Bicarbonate gap(the delta gap/ratio)
➤ The difference between the increase in the anion gap and decrease in
bicarbonate is termed the bicarbonate gap
Normally, increase in anion gap=decrease in the serum bicarbonate
For ex if the anion gap has increased by 8mEq/L the serum bicarbonate is also
expected to fall by 8mEq/L
The increase in the anion gap
significantly exceeds decrease in the
bicarbonate
If the bicarbonate has not fallen
proportionately ,a process that is
contributing to a relative increase in
bicarbonate anticipated
Positve bicarbonate gap >6mEq/L
An associated metabolic alkalosis is
present
The decrease in the bicarbonate
significantly exceeds the increase in
the anion gap
Negative bicarbonate ion gap
<6mEq/L
An associated narrow anion gap
metabolic acidosis is present
41. STEP 7: DETECTING MIXED DISORDERS
➤ Clues to the presence of a mixed disorder
1. Clinical history
2. pH normal, abnormal PCO2 and HCO3
3. PCO2 and HCO3 moving opposite directions
4. Acid base map (flenley nomogram)
5. Degree of compensation for primary disorder is inappropriate
6. Delta gap
42. ➤ Example : in a case of primary metabolic acidosis, HCO3=12
Expected compensated PCO3 will be 24-28
(PCO2=1.5HCO3+8 +/-2) (winter’s formula)
If PCO2 is <24, metabolic acidosis +respiratory alkalosis
If PCO2 is >28, metabolic acidosis + respiratory acidosis
43. Coexistence of acid-base disorders
➤ Frequently two(sometimes three) acid-base disorders occur simultaneously
Two respiratory
disorders cannot
coexist
The lungs cannot
simultaneously
retain and excrete
CO2
Other combinations four acid base disorders are
possible
One metabolic can
occur together
with a respiratory
disturbance
Two metabolic
disorders can
occur together
Two metabolic
disorders can
occur with single
respiratory
disturbance
44. REFERENCES :
1. Handbook of blood gas/ acid-base interpretation, springer
monograph by ashfaq hasan
2. Blood gas analysis by t.shyam sunder
3. newbornwhocc.org
4. Harrison’s internal medicine 19th edition
5. Arterial blood gases made easy 2edition
Thank you