New Guidelines Issued on Treating Drowning in ED
October 4th, 2016
JACKSONVILLE, FL – As the weather warms up, emergency departments see more patients suffering the effects of drowning. More than 3,800 drowning deaths occur in the United States each year, with children 1 to 4 years old who die in residential pools the highest risk group.
The Wilderness Medical Society (WMS) recently issued new guidelines on the treatment of drowning, published in the society's official journal, Wilderness and Environmental Medicine. A team of researchers graded available evidence according to the American College of Chest Physicians criteria.
"Drowning is a process defined by hypoxemia, with outcomes ranging from no morbidity to severe morbidity, and eventually death," explained lead author Andrew C. Schmidt, DO, MPH, assistant professor of Emergency Medicine at the University of Florida College of Medicine in Jacksonville, and director of Lifeguards Without Borders.
Clinical deterioration tends to occur within the first four to eight hours for patients presenting with mild symptoms after drowning, requiring the monitoring of lung sounds, oxygen saturation, and blood pressure, according to the report. For events occurring in the wilderness, the guidelines recommend emergency care if patients exhibit hypoxemia; abnormal lung sounds; severe cough; frothy sputum or foamy material in the airway; depressed mentation; or hypotension.
In terms of post-resuscitation management, the guidelines recommend that mechanical ventilation should follow acute respiratory distress syndrome (ARDS) protocols. The document also suggests that initial chest radiographs could be useful in tracking changes in patient condition but not for determining prognosis.
The document does not call for routine use of neuroimaging in awake and alert drowning patients, however, unless a change in clinical status occurs. Also not recommended is routine complete blood count or electrolyte testing, although arterial blood gas testing might be used for patients who show signs of hypoxemia or respiratory distress in order to guide respiratory interventions.
The guidelines cite a lack of data and evidence on the use of routine antibiotics and corticosteroids, suggesting those might be employed in extenuating clinical circumstances that demand their use.
While current literature indicates that therapeutic hypothermia could offer some benefits to drowning patients, the researchers failed to find enough evidence to either support or discourage its use.
The article points to research suggesting that patients who experience a drowning event but have no symptoms other than a mild cough (and do not have abnormal lung sounds) are almost certain to survive. On the other hand, if a patient is submerged for more than 30 minutes in water warmer than 6°C (43°F) or more than 90 minutes in water colder than 6°C (43°F), the guidelines suggest there is minimal chance of the patient surviving the event neurologically intact.
Patients can be safely discharged from the ED after stabilization if there was no deterioration in respiratory function after four to eight hours of observation on room air, according to the recommendations.
"When prevention fails, or circumstance leads to the drowning process,” Schmidt emphasized, “then the most important aspect of treatment is to reverse cerebral hypoxia by providing oxygen to the brain by whatever means available."