NCM 118: RLE Module 6F: Mechanical Ventilation, Pace Making and ECG Interpretation

a positive or negative pressure breathing device that can maintain ventilation and oxygen delivery for a prolonged period

Mechanical Ventilation

Exerts positive pressure on the airway, pushing air in, similar to a bellows mechanism, and forcing the alveoli to expand during inspiration

Positive Pressure

generated on the outside of the chest and transmitted to the interior to expand the lungs and allow air to flow in

Negative Pressure

The ventilator forces a breath into the lungs whether or not the patient tries to breathe

Mandatory Breath

• The patient breathes on their own using their muscles.

• Air moves in and out naturally, without help from a machine.

Spontaneous Breath

A small device that sends electrical signals to make the heart beat if it’s too slow or irregular

Pacemaker

The wire that carries the signal from the pacemaker to the heart.

Pacemaker Lead

When the pacemaker’s signal successfully makes the heart beat.

Capture

The spike on ECG showing the pacemaker sent a signal

Pacing Artifact

Tiny amount of electric current; 1 mA = 1/1000 of an ampere.

Milliampere (mA)

Pacemaker can detect the heart’s natural beats

Sense

How strong a signal the pacemaker needs to notice a heartbeat

Sensitivity

The minimum signal level needed to make the pacemaker fire a beat. Think: the “trigger point.”

Threshold

The test that records heart’s rhythm and electrical activity.

Electrocardiography (ECG)

• the instrument used to record the heart's electrical activity, while an

• the recording or tracing produced by that instrument

• Electrocardiograph

• Electrocardiogram (ECG/EKG)

A procedure to study and treat serious heart rhythm problems.

Electrophysiology

Sensors that pick up the heart’s electrical signals

Electrodes

Wires that connect devices like pacemakers or ECGs to the heart.

Lead

Ability of cardiac cells to initiate electrical impulses on their own.

Automaticity

Ability of a cell to respond to stimulation by rapid changes in membrane potential via ion fluxes

Excitability

give 2 purposes, indications and contraindications of mechanical ventilation

• Helps the patient to have adequate oxygen

• To prevent injury from aspiration

• Cardiac arrest/ Sepsis

• Asthma

• Tension Pneumothorax

• Hypovolemic shock

give 2 purposes, indications and contraindications of pace making

• To deliver electrical impulses to the cardiac muscle

• Aids in managing heart failure

• Slower-than-normal

• impulse formation

• Asymptomatic atrioventricular block

• Severe bleeding

• Active anticoagulation therapy

give 2 purposes, indications and contraindications of ECG analysis and interpretation

• Evaluate how the heart is functioning

• Diagnose heart illnesses

• Palpitations

• Cyanosis

• Allergic to adhesive used to affix leads

• Patient’s refusal

practice of gradually lowering and eventually discontinuing a patient's mechanical ventilation support

Weaning procedure

Methods of Weaning

• Synchronized Intermittent Mandatory Ventilation (SIMV)

• Pressure-Support Ventilation (PSV)

• Unsupported Spontaneous Breathing Trial

Methods of Weaning

• Patient’s own breaths are synchronized with the decreasing machine breaths

• Think: “Machine and patient breathe together, but machine slowly backs off.”

Synchronized Intermittent Mandatory Ventilation (SIMV)

Methods of Weaning

• All breaths are initiated by the patient.

• Ventilator gives just enough pressure support to assist.

• Think: “Patient leads, machine helps a little.”

Pressure-Support Ventilation (PSV)

Methods of Weaning

• Patient breathes on their own.

• Ventilator support is removed intermittently; a T-Piece or CPAP is used for short rest periods.

Unsupported Spontaneous Breathing Trial

Common PPV Modes

• Continuous Positive Airway Pressure (CPAP)

• BiLevel Positive Airway Pressure (BiPAP)

• High-Frequency Oscillatory Ventilation (HFOV)

• Intermittent Mandatory Ventilation (IMV)

Common NPV Devices

• Iron Lung

• Chest Cuirass