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Vital Signs and the Monitor

You will hear about vital signs several times a day when you are in the hospital.  You may be woken up to have vital signs taken.  In the ER, patients are often placed on a continuous monitor to automatically check vital signs.   In the ICU, patients are on continuous monitoring.   On heart units, or telemetry, the heart rate and rhythm are monitored continuously.  So what are they and how do they look on the monitor?
 










Heart Rate and Rhythm  ❤
Usually it is listed on the top of the monitor.  Normal heart rate is between 60-100 beats per minute for adults. The range is different in children depending on age.  We also look at the rhythm on the monitor.  Is the rhythm regular?  All of the vertical lines will come in a regular pattern.  If the rhythm is irregular, such as an atrial fibrillation, the vertical lines will come in no pattern.  There are rhythms that we need to fix immediately such as ventricular tachycardia, and there are rhythms that we can fix over time.  Usually if the blood pressure is okay and the patient is doing well, we have time to fix the rhythm.

Blood Pressure
Most of us familiar with this, taken by a blood pressure cuff, measured in mmHg – millimeters of mercury.  It is the systolic over the diastolic pressure.  There is a range for normal blood pressure for every age. Normal blood pressure for adults is less than 120 systolic and less than 80 diastolic.  When blood pressure goes low, we rely on the MAP, the mean arterial pressure.  It is reported in brackets after the blood pressure.   For all of the organs of the body to have adequate blood flow the MAP needs to be 65 mmHg or greater.  Sepsis can make the blood pressure go low.  Sometimes continuous intravenous drips are needed to keep the blood pressure up.  This group of medications is called vasopressors.  The most common one used is Levophed.
There are reasons to have the blood pressure run high.  For example, after an “ischemic” stroke (the brain lost blood flow from a clot), research has shown us that the blood pressure must remain higher to help get the blood flow back to the damaged area of brain.

Respiratory Rate
A measure of how fast her breathing.  Normal rate for adults is 12-16 breaths per minute.  Usually you have a little monitor on your finger.  This can also detect your heart rate.  In that case it is called a pulse ox - a pulse oximeter.  When it is on a monitor there is a wave form seen.  To know that the rate is accurate, that wave form will be a nice even, repeating, predictable pattern.

Temperature
Measured by a thermometer or a probe.  A probe can be stuck to the forehead.  A normal body temperature for an adult is usually between 97-99 degrees F or approximately 37° C. It can change according to the time of day.  A fever is defined as greater than or equal to 100.4° F or 38° C. It is common knowledge that an infection can lead to a fever.  Other causes of fever include blood clots, medications, heat exhaustion, cancers, autoimmune disease such as rheumatoid arthritis, after vaccinations, thyroid storm, adrenal insufficiency or even from a transfusion of blood cells.
Low fevers can happen in the elderly as a response to an infection or any stressor to the body.  It is usually not a good sign.  After an out-of-hospital heart attack often times we make a person have low temperature called therapeutic hypothermia.  Other causes of low temperature include a near-drowning, malnutrition, hypothyroidism or exposure to the cold.

Other lines on the monitor:

Intra-arterial catheter (A-Line)
This is placed in patients in the intensive care unit to have a better look at what the blood pressure actually is doing.  Blood pressure monitoring by the cuff is not a perfect measure.  If very close blood pressure monitoring is required, the intensive care unit physician will place an arterial line.  This is also helpful when arterial blood as needed for monitoring of the ventilator (life support).  We monitor are ventilator settings and how the patient is tolerating them through arterial blood gases.  It lets us know our oxygenation (amount of oxygen getting into the blood) and ventilation (the amount of carbon dioxide CO2 coming out of the lungs). More recently we have moved to venous blood gases as they are safer and easier to draw.

Continuous End Tidal CO2 monitoring
This might be a line with a wave form on the monitor in the intensive care unit on a patient who is on the ventilator (life support).  It measures a carbon dioxide coming out of the lung.  Not all ventilated patients need to have this monitored.  It is always checked after the tube is inserted to ensure that there is carbon dioxide coming out of the tube.  This quickly lets us know that the tube is in the correct position in the lung.  Normal levels range from the 30s to 40s, but is specific to patient factors.  If it goes up to 50 that means there is a lot of carbon dioxide being generated and maybe the patient is hypoventilation.  Meaning, the respiratory rate is too slow.
 
When in the intensive care unit the physician and nurses are monitoring other things as well.  Particularly, the volume of fluids going in and the amount of urine that is coming out during a 24 hour period and a running tally for the entire stay.  While this is not a vital sign, it is very important to the health of the patient.

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