- •ICU Protocols
- •Preface
- •Acknowledgments
- •Contents
- •Contributors
- •1: Airway Management
- •Suggested Reading
- •2: Acute Respiratory Failure
- •Suggested Reading
- •Suggested Reading
- •Website
- •4: Basic Mechanical Ventilation
- •Suggested Reading
- •Suggested Reading
- •Websites
- •Suggested Reading
- •Websites
- •7: Weaning
- •Suggested Reading
- •8: Massive Hemoptysis
- •Suggested Reading
- •9: Pulmonary Thromboembolism
- •Suggested Reading
- •Suggested Reading
- •Websites
- •11: Ventilator-Associated Pneumonia
- •Suggested Readings
- •12: Pleural Diseases
- •Suggested Reading
- •Websites
- •13: Sleep-Disordered Breathing
- •Suggested Reading
- •Websites
- •14: Oxygen Therapy
- •Suggested Reading
- •15: Pulse Oximetry and Capnography
- •Conclusion
- •Suggested Reading
- •Websites
- •16: Hemodynamic Monitoring
- •Suggested Reading
- •Websites
- •17: Echocardiography
- •Suggested Readings
- •Websites
- •Suggested Reading
- •Websites
- •19: Cardiorespiratory Arrest
- •Suggested Reading
- •Websites
- •20: Cardiogenic Shock
- •Suggested Reading
- •21: Acute Heart Failure
- •Suggested Reading
- •22: Cardiac Arrhythmias
- •Suggested Reading
- •Website
- •23: Acute Coronary Syndromes
- •Suggested Reading
- •Website
- •Suggested Reading
- •25: Aortic Dissection
- •Suggested Reading
- •26: Cerebrovascular Accident
- •Suggested Reading
- •Websites
- •27: Subarachnoid Hemorrhage
- •Suggested Reading
- •Websites
- •28: Status Epilepticus
- •Suggested Reading
- •29: Acute Flaccid Paralysis
- •Suggested Readings
- •30: Coma
- •Suggested Reading
- •Suggested Reading
- •Websites
- •32: Acute Febrile Encephalopathy
- •Suggested Reading
- •33: Sedation and Analgesia
- •Suggested Reading
- •Websites
- •34: Brain Death
- •Suggested Reading
- •Websites
- •35: Upper Gastrointestinal Bleeding
- •Suggested Reading
- •36: Lower Gastrointestinal Bleeding
- •Suggested Reading
- •37: Acute Diarrhea
- •Suggested Reading
- •38: Acute Abdominal Distension
- •Suggested Reading
- •39: Intra-abdominal Hypertension
- •Suggested Reading
- •Website
- •40: Acute Pancreatitis
- •Suggested Reading
- •Website
- •41: Acute Liver Failure
- •Suggested Reading
- •Suggested Reading
- •Websites
- •43: Nutrition Support
- •Suggested Reading
- •44: Acute Renal Failure
- •Suggested Reading
- •Websites
- •45: Renal Replacement Therapy
- •Suggested Reading
- •Website
- •46: Managing a Patient on Dialysis
- •Suggested Reading
- •Websites
- •47: Drug Dosing
- •Suggested Reading
- •Websites
- •48: General Measures of Infection Control
- •Suggested Reading
- •Websites
- •49: Antibiotic Stewardship
- •Suggested Reading
- •Website
- •50: Septic Shock
- •Suggested Reading
- •51: Severe Tropical Infections
- •Suggested Reading
- •Websites
- •52: New-Onset Fever
- •Suggested Reading
- •Websites
- •53: Fungal Infections
- •Suggested Reading
- •Suggested Reading
- •Website
- •55: Hyponatremia
- •Suggested Reading
- •56: Hypernatremia
- •Suggested Reading
- •57: Hypokalemia and Hyperkalemia
- •57.1 Hyperkalemia
- •Suggested Reading
- •Website
- •58: Arterial Blood Gases
- •Suggested Reading
- •Websites
- •59: Diabetic Emergencies
- •59.1 Hyperglycemic Emergencies
- •59.2 Hypoglycemia
- •Suggested Reading
- •60: Glycemic Control in the ICU
- •Suggested Reading
- •61: Transfusion Practices and Complications
- •Suggested Reading
- •Websites
- •Suggested Reading
- •Website
- •63: Onco-emergencies
- •63.1 Hypercalcemia
- •63.2 ECG Changes in Hypercalcemia
- •63.3 Superior Vena Cava Syndrome
- •63.4 Malignant Spinal Cord Compression
- •Suggested Reading
- •64: General Management of Trauma
- •Suggested Reading
- •65: Severe Head and Spinal Cord Injury
- •Suggested Reading
- •Websites
- •66: Torso Trauma
- •Suggested Reading
- •Websites
- •67: Burn Management
- •Suggested Reading
- •68: General Poisoning Management
- •Suggested Reading
- •69: Syndromic Approach to Poisoning
- •Suggested Reading
- •Websites
- •70: Drug Abuse
- •Suggested Reading
- •71: Snakebite
- •Suggested Reading
- •72: Heat Stroke and Hypothermia
- •72.1 Heat Stroke
- •72.2 Hypothermia
- •Suggested Reading
- •73: Jaundice in Pregnancy
- •Suggested Reading
- •Suggested Reading
- •75: Severe Preeclampsia
- •Suggested Reading
- •76: General Issues in Perioperative Care
- •Suggested Reading
- •Web Site
- •77.1 Cardiac Surgery
- •77.2 Thoracic Surgery
- •77.3 Neurosurgery
- •Suggested Reading
- •78: Initial Assessment and Resuscitation
- •Suggested Reading
- •79: Comprehensive ICU Care
- •Suggested Reading
- •Website
- •80: Quality Control
- •Suggested Reading
- •Websites
- •81: Ethical Principles in End-of-Life Care
- •Suggested Reading
- •82: ICU Organization and Training
- •Suggested Reading
- •Website
- •83: Transportation of Critically Ill Patients
- •83.1 Intrahospital Transport
- •83.2 Interhospital Transport
- •Suggested Reading
- •84: Scoring Systems
- •Suggested Reading
- •Websites
- •85: Mechanical Ventilation
- •Suggested Reading
- •86: Acute Severe Asthma
- •Suggested Reading
- •87: Status Epilepticus
- •Suggested Reading
- •88: Severe Sepsis and Septic Shock
- •Suggested Reading
- •89: Acute Intracranial Hypertension
- •Suggested Reading
- •90: Multiorgan Failure
- •90.1 Concurrent Management of Hepatic Dysfunction
- •Suggested Readings
- •91: Central Line Placement
- •Suggested Reading
- •92: Arterial Catheterization
- •Suggested Reading
- •93: Pulmonary Artery Catheterization
- •Suggested Reading
- •Website
- •Suggested Reading
- •95: Temporary Pacemaker Insertion
- •Suggested Reading
- •96: Percutaneous Tracheostomy
- •Suggested Reading
- •97: Thoracentesis
- •Suggested Reading
- •98: Chest Tube Placement
- •Suggested Reading
- •99: Pericardiocentesis
- •Suggested Reading
- •100: Lumbar Puncture
- •Suggested Reading
- •Website
- •101: Intra-aortic Balloon Pump
- •Suggested Reading
- •Appendices
- •Appendix A
- •Appendix B
- •Common ICU Formulae
- •Appendix C
- •Appendix D: Syllabus for ICU Training
- •Index
Oxygen Therapy |
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Surinder K. Jindal and Ashutosh Nath Aggarwal |
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A young female patient presented to the emergency department with history of sore throat, high-grade fever, and cough with minimal hemoptysis for the past 5 days. On examination, she was found to be in respiratory distress. Her chest examination report was normal. The chest skiagram showed bilateral infiltrates and SpO2 was 80%.
Oxygen is the commonest drug used in patients admitted in Intensive Care Unit. There are various methods available for delivering oxygen. Overzealous treatment with oxygen should be avoided due to the risk of oxygen toxicity.
Step 1: Assess the need for oxygen therapy
•The need for oxygen therapy in the intensive care unit (ICU) depends on the presence of documented hypoxia and/or inadequate oxygenation.
•Presence of nonspecific symptoms and signs suggestive of hypoxia should be evaluated with objective measurements of oxygenation.
•Arterial blood gas analysis with measurement of oxygen (PaO2) and carbon dioxide (PaCO2) partial pressures remains the gold standard for hypoxia demonstration.
•Pulse oximetry is a noninvasive method, which provides arterial oxygen satura-
tion (SpO2) as a substitute for PaO2 for routine monitoring. The reading of pulse oximetry could be inconsistent (see Chap. 15).
Oxygen is applied if any of the following is present:
• Hypoxia (i.e., PaO2 <60 mmHg) due to any cause.
S.K. Jindal, M.D. (*) • A.N. Aggarwal, M.D., D.M.
Department of Pulmonary Medicine, Postgraduate Institute of Medical Education & Research, Chandigarh, India
e-mail: drskjindal@gmail.com
R. Chawla and S. Todi (eds.), ICU Protocols: A stepwise approach, |
107 |
DOI 10.1007/978-81-322-0535-7_14, © Springer India 2012 |
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S.K. Jindal and A.N. Aggarwal |
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•Respiratory failure due to
–Acute respiratory distress syndrome
–Acute exacerbation of chronic obstructive pulmonary disease (COPD) or asthma
–Pneumonia
•In emergency situations (e.g., cardiorespiratory arrest, acute cardiogenic pulmonary edema, or stroke), oxygen administration may be initiated empirically, pending detailed clinical and laboratory evaluation. Blood gas analysis should be made available as early as possible.
•Normoxemic hypoxia (i.e., normal PaO2) but presence of tissue hypoxia in the following conditions:
–Severe anemia
–Low cardiac output state
–Hypotension
–Severe sepsis
–Vascular (arterial) occlusion
•Failure of tissues to utilize oxygen (e.g., poisoning)—histotoxic hypoxia.
Step 2: Initiate oxygen administration
•Before giving oxygen, one needs to ensure patency of the airways. This might require endotracheal intubation or tracheostomy.
•It is generally customary to start with a high FiO2—100% for cardiorespiratory arrest and 50–100% for acute hypoxemic respiratory failure.
•The FiO2 can be increased or decreased after the assessment of clinical and laboratory response to the initial administration.
•Relatively lower concentrations are used in patients with hypercapnic respiratory failure (such as COPD) with the preexisting chronic hypoventilation.
•High concentration of oxygen may worsen CO2 retention and cause CO2 narcosis by abolishing the hypoxic respiratory stimulation. However, optimum FiO2 must be ensured since hypoxia is always more deleterious than hypercapnia. Various devices can be used for applying oxygen.
Administration Devices
1.Source: Most well-equipped ICUs have continuous pressurized oxygen and air supply available at each bed. In this fashion, both oxygen and air can be simulta-
neously fed into an oxygen blender to control the output FiO2. Oxygen cylinders and concentrators are required as a backup source in case of failure of central supply.
2.Oxygen delivery: Oxygen is delivered either alone noninvasively or along with assisted respiratory support.
A. Stand-alone oxygen
•The ICU patients are sicker with high ventilatory requirements than the general ward patients. Higher concentrations of oxygen are required, which are provided with high-flow systems.
14 Oxygen Therapy |
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Fig. 14.1 Simple face mask
Nasal cannulation is usually insufficient in severe hypoxemic respiratory failure. The nasal cannula is a low-flow, low-oxygen device and cannot deliver tracheal FiO2 more than 0.4–0.5. High flow rates do not result in high FiO2 and have a drying and irritating effect on nasal mucosa.
Simple face mask is a low-flow delivery system which provides FiO2 from 0.4 to 0.6 at flow rate of 5–8 L/min. This mask does not need tight seal (Fig. 14.1).
Venturi masks are preferred for precise titration of oxygen being administered. FiO2 can be more precisely controlled from 0.24 to 0.5 at high flow rates simply by changing the jet nozzle and adjusting oxygen flow rates. This is particularly helpful in patients with acute exacerbation of COPD where controlled oxygen supplementation is quite critical (Fig. 14.2).
•Oxygen delivery is also provided through a mask with a reservoir, which
is a high-oxygen, high-flow device. A high FiO2 of up to 0.6–0.9 can be delivered through these masks (Figs. 14.3 and 14.4).
B.O2 supplementation during noninvasive positive-pressure ventilation (NIPPV)
•NIPPV in ICUs is administered either through conventional mechanical ventilation or through a portable system.
•Supplemental oxygen is delivered by simply adding it to the mask or the circuit.
•Oxygen should be added into the circuit distal to the exhalation port.
•The highest concentration is achieved with O2 added to the mask, with the leak port in the circuit, and with the lowest setting of inspiratory and expi-
ratory pressures. Unfortunately, the delivered FiO2 with NIPPV portable systems remains unpredictable.
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S.K. Jindal and A.N. Aggarwal |
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Fig. 14.2 Schematic diagram showing the principle involved in the venturi mask
Fig. 14.3 Schematic diagram showing the principle of partial non-rebreather mask
Fig. 14.4 Schematic diagram showing the principle of non-rebreather face mask