med 18

 

 Patients may fall or j urnp into a

body of water and their distress is immediately noted or

alternatively may be found floating or at the bottom of a

lake or pool after a period of t ime without being seen.

Symptoms also vary. Patients may be asymptomatic or

may present with severe illness. Clinical effects of the s ubmersion/immersion event itself most often manifest as

respiratory abnormalities including hypoxia, tachypnea, or

abnormal lung sounds. Depending on the season, patients

may be hypothermic. At severe levels of illness, cardiac

dysrhythmias may occur, and mental status can change.

Most, if not all, drownings involve aspiration. "Dry drowning" (hypoxia from laryngospasm without aspiration) is

thought to be extremely rare and physiologically difficult

to explain.

� History

Drowned patients should be initially evaluated like major

trauma patients, with attention to the airway, breathing,

and circulation (ABCs) and rapid assessment of an AMPLE

history. When evaluating a patient who has experienced a

drowning incident, the following information must be

obtained:

• Events surrounding the incident (How did they end

up in the water? Did they sustain any trauma?)

• Temperature of the water and air

270

DROWNING INCIDENTS

• Length of time in the water, length of time

underwater

• Status on retrieval from the water (respiratory, mental status, cardiovascular, color)

• Was any immediate treatment needed?

• Current symptoms?

It will also be important to consider the potential of

suicide; the medical status of the patient will dictate how

urgently this assessment is needed .

..... Physical Examination

The order of the physical exam will depend on patient

stability. Assess the unstable patient like a trauma patient,

with a primary survey and management as necessary, followed by a thorough secondary survey. In the stable

patient, an examination can be conducted in a head-to-toe

fashion. Areas of focus include signs of external trauma,

especially the head and neck, lung sounds to evaluate for

water or emesis aspiration, skin color (cyanosis), core body

temperature (rectal), and a neurologic exam.

DIAGNOSTIC STUDIES

..... Laboratory

No specific laboratory testing is universally recommended

for drowned patients. If the provider feels that significant

aspiration occurred, or if the patient is unstable, useful labo ­

ratory tests to determine the severity of injury include a

blood count, serum electrolytes, and blood gases. To assess

the pH, a venous gas is sufficient. Electrolyte changes may

occur if large volumes of water are aspirated. Animal studies

have shown that 11 mL/kg of aspirated hypotonic fluid are

necessary before any effect is seen on hemoglobin, volume

status, or electrolytes. Most drowning victims aspirate less

than 4 mL/kg. In the majority of cases, hypoxia and metabolic acidosis cause the resultant morbidity and mortality.

Other laboratory studies may be indicated in certain

patients. Assessment of blood alcohol level, drug ingestions,

and medical causes for the patient's submersion (myocardial

infarction, syncope, stroke) should be considered.

..... Imaging

Patients in whom significant aspiration is suspected should

undergo chest radiography. The most common finding is

an aspiration pneumonitis (Figure 64- l). Head and cervi ­

cal spine imaging should be considered if the patient dived

into the water. Any other traumatic injuries noted on exam

or suspected by history should be imaged and evaluated as

appropriate.

MEDICAL DECISION MAKING

When a patient presents after a drowning incident, stabilization is the first priority. Once the patient is stabilized,

a detailed history of events and a thorough physical

..&. Figure 64-1. Aspiration pneumonitis. Reprinted

with permission from Heitz CR. "Drown ing Incidents."

CDEM Curricu lum, 2009. Available at: http:/ jwww

.cdemcurricu lum.orgji ndex.phpjssmjshow_ssm/

envirojdrowning.php.

exam should be obtained. The focus of the evaluation is

2-fold:

1. To determine types and extent of injury (aspiration,

exposure, trauma)

2. To determine whether this is a primary or secondary

drowning incident

Secondary drowning refers to a drowning incident that

occurred as a result of a medical event, drug or alcohol

ingestion, or preceding trauma. For instance, a boater who

drowns in a lake may have ingested a large amount of alco ­

hol, causing him to fall into the water. A diver may strike

her head on the bottom of the pool, causing prolonged

submersion. Figure 64-2 delineates a suggested algorithm

for management of the drowned patient.

TREATMENT

Initial stabilization and supportive care are the mainstays

of emergency department (ED) treatment for drowned

patients. Airway protection, management of hypoxia and

hypothermia, and urgent/emergent treatment of traumatic

injuries or medical emergencies take first priority. This

may include placement of an endotracheal t ube, high-flow

oxygen, active rewarming, and volume resuscitation.

Patients who have aspirated large volumes may require

positive pressure ventilation to recruit collapsed alveoli. If

intubated and large-volume aspiration occurred, consider

suctioning. Manage any cardiac dysrhythmias as recommended by Advanced Cardiac Life Support protocols.

Treatments once suggested but not currently recommended are prophylactic antibiotics or steroids. In addition,

hyperbaric chamber use has not been shown to be beneficial

unless decompression illness complicates the drowning.

CHAPTER 64