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  1. <Medical Topics
    Critical Care Medicine
    Approach to the Critically Ill Patient
    • Introduction to the Approach to the Critically Ill Patient
    • Monitoring and Testing the Critical Care Patient
      • General references
      • Blood Tests
        • Blood tests references
      • Cardiac Monitoring
      • Pulmonary Artery Catheter (PAC) Monitoring
        • Procedure
        • Pulmonary artery occlusion pressure (pulmonary artery wedge pressure)
        • Mixed venous oxygenation
        • Cardiac output (CO)
        • Complications
        • Pulmonary artery catheter monitoring references
      • Noninvasive Cardiac Output Assessment
        • Point-of-care ultrasound
        • Esophageal Doppler monitor (EDM)
        • Thoracic bioimpedance
        • Noninvasive cardiac output assessment references
      • Intracranial Pressure (ICP) Monitoring
      • Near Infrared Spectroscopy (NIRS)
        • Near infrared spectroscopy references
    • Critical Care Scoring Systems
    • Vascular Access
      • Peripheral Vein Catheterization
      • Central Venous Catheterization
        • Complications of central venous catheterization
        • Central venous catheterization references
      • Midline Peripheral Catheterization
        • Midline peripheral catheterization references
      • Arterial Catheterization
        • Complications of arterial catheterization
      • Intraosseous Infusion
    • Hypoxia in Hospitalized Patients
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Testing
      • Treatment
        • Oxygen therapy
      • Key Points
    • Oliguria
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Testing
      • Treatment
      • Key Points
    • Agitation, Confusion, and Neuromuscular Blockade in Critically Ill Patients
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Testing
      • Treatment
        • Analgesia
        • Sedation
        • Neuromuscular blockade
        • Treatment references
      • Key Points
    Cardiac Arrest and Cardiopulmonary Resuscitation (CPR)
    • Cardiopulmonary Resuscitation (CPR) in Infants and Children
      • General reference
      • Major Differences Between Pediatric and Adult CPR
        • Prearrest
        • Chest compressions
        • Medications
        • Blood pressure
        • Equipment and environment
        • Temperature management
        • Airway and ventilation
        • Defibrillation
        • Treatment references
      • More Information
    • Cardiac Arrest
      • General references
      • Etiology
        • Etiology references
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis references
      • Treatment
        • Treatment references
      • Prognosis
        • Prognosis references
    • Cardiopulmonary Resuscitation (CPR) in Adults
      • Overview of CPR
      • General references
      • CPR: Airway and Breathing
        • Airway and breathing references
      • CPR: Circulation
        • Chest compressions
        • Complications of chest compression
        • Circulation reference
      • CPR: Defibrillation
      • CPR: Monitoring and IV Access
      • CPR: Special Circumstances
      • CPR: Medications for ACLS
        • First-line medications
        • Other medications
        • Medications for ACLS references
      • Arrhythmia Treatment in CPR
      • CPR: Termination of Resuscitation
        • Termination of resuscitation references
      • CPR: Postresuscitative Care
        • Coronary angiography
        • Neurologic support
        • Blood pressure support
        • Post-return of spontaneous circulation arrhythmia treatment
        • Postresuscitative care references
      • More Information
    How To Do Basic Airway Procedures
    • How To Insert a Nasopharyngeal Airway
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
      • Reference
    • How To Insert an Oropharyngeal Airway
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
    • How To Do Abdominal Thrusts and Back Blows in the Conscious Adult or Child Who Is Choking
      • Indications
      • Contraindications
      • Complications
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    • How To Do Head Tilt–Chin Lift and Jaw-Thrust Maneuvers
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Reference
    • How To Treat the Choking Conscious Infant
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    • How To Do Bag-Valve-Mask (BVM) Ventilation
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • References
    How To Do Other Airway Procedures
    • How To Do a Percutaneous Needle Cricothyrotomy
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Reference
    • How To Insert an Esophageal-Tracheal Double Lumen Tube or a Laryngeal Tube
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
      • Reference
    • How To Do Noninvasive Positive Pressure Ventilation
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Tips and Tricks
    • How To Do a Percutaneous Cricothyrotomy
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Tips and Tricks
      • Reference
    • How To Do Orotracheal Intubation Using Video Laryngoscopy
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    • How To Insert a Laryngeal Mask Airway
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    How To Do Central Vascular Procedures
    • How To Do Infraclavicular Subclavian Vein Cannulation
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Seldinger (catheter-over-guidewire) technique
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment
        • Prepare the sterile field
        • Establish the needle insertion path (subclavian vein, infraclavicular approach)
        • Anesthetize the cannulation site
        • Insert the introducer needle (or finder needle, optional)
        • Assess the blood return
        • Optional: Use the finder needle to guide insertion of the introducer needle
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Widen the insertion tract
        • Place the catheter
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
    • How To Do Internal Jugular Vein Cannulation
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Seldinger (catheter-over-guidewire) technique
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment
        • Prepare the sterile field
        • Establish the needle insertion path (internal jugular vein, central approach)
        • Anesthetize the cannulation site
        • Insert the finder needle
        • Assess the blood return
        • Insert the introducer needle, using the finder needle as a guide
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Widen the insertion tract
        • Place the catheter
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
    • How To Do Internal Jugular Vein Cannulation, Ultrasound-Guided
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Ultrasound guidance
        • Seldinger (catheter-over-guidewire) technique
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Preliminary preparation (nonsterile)
        • Prepare the equipment
        • Prepare the sterile field
        • Place a sterile cover over the ultrasound probe
        • Anesthetize the cannulation site
        • Insert the introducer needle
        • Assess the blood return
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Widen the insertion tract
        • Place the catheter
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
    • How To Do Femoral Vein Cannulation (Without Ultrasound Guidance)
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Seldinger (catheter-over-guidewire) technique
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment
        • Prepare the sterile field
        • Establish the needle insertion path
        • Anesthetize the cannulation site
        • Insert the introducer needle (or finder needle, optional)
        • Assess the blood return
        • Optional: Use the finder needle to guide insertion of the introducer needle
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Widen the insertion tract
        • Place the catheter
        • Dress the site
      • Warnings and Common Errors
      • Tips and Tricks
    • How To Do Infraclavicular Subclavian Vein Cannulation, Ultrasound-Guided
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Ultrasound guidance
        • Seldinger (catheter-over-guidewire) technique
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment
        • Prepare the sterile field
        • Place a sterile cover over the ultrasound probe
        • Anesthetize the cannulation site
        • Insert the introducer needle using ultrasound guidance
        • Assess the blood return
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Widen the insertion tract
        • Place the catheter
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
    • How To Do Femoral Vein Cannulation, Ultrasound-Guided
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Ultrasound guidance
        • Seldinger (catheter-over-guidewire) technique
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Preliminary preparation (nonsterile)
        • Prepare the equipment
        • Prepare the sterile field
        • Place a sterile cover over the ultrasound probe
        • Anesthetize the cannulation site
        • Insert the introducer needle
        • Assess the blood return
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Widen the insertion tract
        • Place the catheter
        • Dress the site
      • Warnings and Common Errors
      • Tips and Tricks
    • How To Do Femoral Artery Cannulation, Ultrasound-Guided
      • Indications
      • Contraindications
      • Complications
      • Equipment
        • Sterile procedure, barrier protection
        • Ultrasound guidance
        • Seldinger (catheter-over-guidewire) technique
        • Arterial pressure monitoring
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment
        • Prepare the sterile field
        • Place a sterile cover over the ultrasound probe
        • Anesthetize the cannulation site
        • Insert the femoral artery introducer needle using ultrasound guidance
        • Insert the guidewire
        • Remove the introducer needle (after successful guidewire insertion)
        • Extend the skin insertion site
        • Place the catheter
        • Dress the site
      • Warnings and Common Errors
    How To Do Peripheral Vascular Procedures
    • How To Insert a Peripheral Intravenous Catheter
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Identify and prepare the site
        • Insert the peripheral venous catheter
        • Begin the IV infusion/establish the saline lock
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
    • How To Do Ultrasound-Guided Peripheral Intravenous Catheter Insertion
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the ultrasound device and identify a candidate vein
        • Insert the peripheral venous catheter using ultrasound guidance
        • Begin the IV infusion/establish the saline lock
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    • How To Insert a Radial Artery Catheter
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment and the sterile field
        • Anesthetize the cannulation site
        • Insert the needle into the artery
        • Assess the blood return
        • Thread the arterial catheter
        • Connect the arterial line
        • Dress the site
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    • How To Do Ultrasound-Guided Radial Artery Catheter Insertion
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the ultrasound device and identify the radial artery
        • Prepare the equipment and the sterile field
        • Place a sterile cover over the ultrasound probe
        • Anesthetize the cannulation site
        • Insert the needle into the radial artery using ultrasound guidance
        • Assess the blood return
        • Thread the arterial catheter
        • Connect the arterial line
        • Dress the site
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    • How To Place an Intraosseous Catheter, Manually and With a Power Drill
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Prepare the equipment and the insertion site
        • Anesthetize the needle insertion site
        • Insert the intraosseous needle
        • Confirm intramedullary needle placement
        • Begin intramedullary infusion
        • Dress the site
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • References
    • How To Do Venous Blood Sampling
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Identify and prepare the site
        • Obtain the blood sample
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • Reference
    How To Do Other Emergency Medicine Procedures
    • How To Do Diagnostic Peritoneal Lavage (DPL)
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Positioning
      • Relevant Anatomy
      • Step-by-Step Description of Procedure
        • Prepare the patient
        • Access the peritoneal cavity
        • Do the peritoneal lavage
      • Aftercare
      • Warnings and Common Errors
      • Tips and Tricks
      • References
    • How To Do E-FAST Examination
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Positioning
      • Relevant Anatomy
      • Step-by-Step Description of Procedure
        • Pericardial view (cardiac)
        • Perihepatic view (right upper quadrant)
        • Perisplenic view (left upper quadrant)
        • Pelvic view (suprapubic)
        • Thoracic view
      • Warnings and Common Errors
      • Tips and Tricks
      • References
    • How To Do Ultrasound
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Step-by-Step Description of Procedure
        • Choose a probe
        • Operate the ultrasound console
        • Maneuver the probe do ultrasound imaging
      • Warnings and Common Errors
      • Tips and Tricks
    Respiratory Arrest
    • Airway and Respiratory Devices
      • Bag-Valve-Mask Devices
      • Laryngeal Mask Airways (LMA)
      • Endotracheal Tubes
      • Other Devices
    • Tracheal Intubation
      • Before Intubation
        • Evaluation of the airway
        • Preparing for intubation
        • Before intubation references
      • Tube Selection and Preparation for Intubation
        • Tube selection reference
      • Insertion Technique for Intubation
        • Insertion technique references
      • Alternative Intubation Devices
        • Alternative intubation devices references
      • Confirming Tube Placement
      • Nasotracheal Intubation
      • Complications of Tracheal Intubation
        • Complications of intubation reference
    • Surgical Airway
      • Cricothyrotomy
      • Tracheostomy
    • Medications to Aid Intubation
      • Sedation and analgesia for intubation
      • Medications to cause paralysis for intubation
      • Topical anesthesia for intubation
      • Post-intubation sedation and analgesia
      • References
    • Overview of Respiratory Arrest
      • Etiology
        • Airway obstruction
        • Decreased respiratory effort
        • Respiratory muscle weakness
        • Etiology references
      • Symptoms and Signs
        • Impending respiratory arrest
        • Symptoms and signs references
      • Diagnosis
        • Diagnosis references
      • Treatment
        • Treatment reference
    • Airway Establishment and Control
      • General references
      • Clearing and Opening the Upper Airway
        • Heimlich maneuver (subdiaphragmatic abdominal thrusts)
    Respiratory Failure and Mechanical Ventilation
    • Noninvasive Positive Pressure Ventilation (NIPPV)
    • Overview of Respiratory Failure
    • Overview of Mechanical Ventilation
      • Indications
      • Respiratory Mechanics
      • Means and Modes of Mechanical Ventilation
        • Volume-cycled ventilation
        • Pressure-cycled ventilation
        • Ventilator settings
        • Patient positioning
        • Means and modes references
      • Sedation and Comfort for Mechanical Ventilation
        • Sedation and comfort references
      • Complications of Mechanical Ventilation and Safeguards
        • Complications of endotracheal intubation
        • Complications of mechanical ventilation itself
        • Complications of immobility
        • Safeguards to reduce complications of mechanical ventilation
    • Acute Hypoxemic Respiratory Failure (AHRF, ARDS)
      • Etiology
      • Pathophysiology
        • ARDS
        • Refractory hypoxemia
        • Pathophysiology references
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Mechanical ventilation in cardiogenic pulmonary edema
        • Mechanical ventilation in ARDS
        • Treatment references
      • Prognosis
        • Prognosis reference
    • Ventilatory Failure
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
        • Determination of cause
      • Treatment
        • Status asthmaticus
        • Acute-on-chronic respiratory failure
    • Other Types of Respiratory Failure
    • Liberation from Mechanical Ventilation
      • References
    Sepsis and Septic Shock
    • Sepsis and Septic Shock
      • General references
      • Etiology and Risk Factors
        • Etiology references
      • Pathophysiology
        • Pathophysiology references
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis references
      • Treatment
        • Perfusion restoration
        • Oxygen support
        • Antibiotics
        • Infection source control
        • Other supportive measures
        • Treatment references
      • Prognosis
        • Prognosis references
      • Key Points
    Shock and Fluid Resuscitation
    • Shock
      • Pathophysiology
        • Compensation for shock
        • Reperfusion following shock
        • Multiple organ dysfunction syndrome (MODS)
      • Etiology and Classification
        • Hypovolemic shock
        • Distributive shock
        • Cardiogenic and obstructive shock
        • Etiology and classification references
      • Symptoms and Signs
      • Diagnosis
        • Identifying etiology
        • Additional testing
        • Diagnosis references
      • Treatment
        • General management of shock
        • Treatment of hemorrhagic shock
        • Treatment of distributive shock
        • Treatment of cardiogenic shock
        • Treatment references
      • Prognosis
    • Intravenous Fluid Resuscitation
      • Fluids
        • Hemorrhage
        • Nonhemorrhagic hypovolemia
        • Fluids references
      • Route and Rate of Fluid Administration
      • End Point and Monitoring of Fluid Resuscitation
        • Central venous pressure
        • Traumatic hemorrhagic shock
      • Complications
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