Advanced Trauma Life Support ATLS Student Course Manual 2018
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
ADJUNCTS TO THE PRIMARY SURVEY WITH RESUSCITATION 11<br />
indicate blunt cardiac injury. Pulseless electrical<br />
activity (PEA) can indicate cardiac tamponade, tension<br />
pneumothorax, and/or profound hypovolemia. When<br />
bradycardia, aberrant conduction, and premature beats<br />
are present, hypoxia and hypoperfusion should be<br />
suspected immediately. Extreme hypothermia also<br />
produces dysrhythmias.<br />
Pulse Oximetry<br />
Pulse oximetry is a valuable adjunct for monitoring<br />
oxygenation in injured patients. A small sensor is<br />
placed on the finger, toe, earlobe, or another convenient<br />
place. Most devices display pulse rate and oxygen<br />
saturation continuously. The relative absorption of<br />
light by oxyhemoglobin (HbO) and deoxyhemoglobin is<br />
assessed by measuring the amount of red and infrared<br />
light emerging from tissues traversed by light rays<br />
and processed by the device, producing an oxygen<br />
saturation level. Pulse oximetry does not measure<br />
the partial pressure of oxygen or carbon dioxide.<br />
Quantitative measurement of these parameters occurs<br />
as soon as is practical and is repeated periodically to<br />
establish trends.<br />
In addition, hemoglobin saturation from the pulse<br />
oximeter should be compared with the value obtained<br />
from the ABG analysis. Inconsistency indicates that<br />
one of the two determinations is in error.<br />
Ventilatory Rate, Capnography, and<br />
Arterial Blood Gases<br />
Ventilatory rate, capnography, and ABG measurements<br />
are used to monitor the adequacy of the<br />
patient’s respirations. Ventilation can be monitored<br />
using end tidal carbon dioxide levels. End tidal CO 2<br />
can be detected using colorimetry, capnometry, or<br />
capnography—a noninvasive monitoring technique<br />
that provides insight into the patient’s ventilation,<br />
circulation, and metabolism. Because endotracheal<br />
tubes can be dislodged whenever a patient is moved,<br />
capnography can be used to confirm intubation of the<br />
airway (vs the esophagus). However, capnography<br />
does not confirm proper position of the tube within<br />
the trachea (see Chapter 2: Airway and Ventilatory<br />
Management). End tidal CO 2<br />
can also be used for tight<br />
control of ventilation to avoid hypoventilation and<br />
hyperventilation. It reflects cardiac output and is used<br />
to predict return of spontaneous circulation(ROSC)<br />
during CPR.<br />
In addition to providing information concerning<br />
the adequacy of oxygenation and ventilation, ABG<br />
values provide acid base information. In the trauma<br />
setting, low pH and base excess levels indicate<br />
shock; therefore, trending these values can reflect<br />
improvements with resuscitation.<br />
Urinary and Gastric Catheters<br />
The placement of urinary and gastric catheters occurs<br />
during or following the primary survey.<br />
Urinary Catheters<br />
Urinary output is a sensitive indicator of the<br />
patient’s volume status and reflects renal perfusion.<br />
Monitoring of urinary output is best accomplished<br />
by insertion of an indwelling bladder catheter. In<br />
addition, a urine specimen should be submitted for<br />
routine laboratory analysis. Transurethral bladder<br />
catheterization is contraindicated for patients who<br />
may have urethral injury. Suspect a urethral injury in<br />
the presence of either blood at the urethral meatus or<br />
perineal ecchymosis.<br />
Accordingly, do not insert a urinary catheter before<br />
examining the perineum and genitalia. When urethral<br />
injury is suspected, confirm urethral integrity by<br />
performing a retrograde urethrogram before the<br />
catheter is inserted.<br />
At times anatomic abnormalities (e.g., urethral<br />
stricture or prostatic hypertrophy) preclude placement<br />
of indwelling bladder catheters, despite appropriate<br />
technique. Nonspecialists should avoid excessive<br />
manipulation of the urethra and the use of specialized<br />
instrumentation. Consult a urologist early.<br />
Gastric Catheters<br />
A gastric tube is indicated to decompress stomach<br />
distention, decrease the risk of aspiration, and check<br />
for upper gastrointestinal hemorrhage from trauma.<br />
Decompression of the stomach reduces the risk of<br />
aspiration, but does not prevent it entirely. Thick and<br />
semisolid gastric contents will not return through the<br />
tube, and placing the tube can induce vomiting. The<br />
tube is effective only if it is properly positioned and<br />
attached to appropriate suction.<br />
Blood in the gastric aspirate may indicate oropharyngeal<br />
(i.e., swallowed) blood, traumatic insertion, or<br />
actual injury to the upper digestive tract. If a fracture<br />
of the cribriform plate is known or suspected, insert<br />
the gastric tube orally to prevent intracranial passage.<br />
In this situation, any nasopharyngeal instrumentation<br />
is potentially dangerous, and an oral route<br />
is recommended.<br />
n BACK TO TABLE OF CONTENTS
Change language