Near Drowning

Near drowning refers to surviving­temporarily, at least-the physiologic effects of hypoxemia and acidosis that result from submersion in fluid. Hypoxemia and acidosis are the primary problems in victims of near drowning.

Near drowning occurs in three forms:

• "dry"-the victim doesn't aspirate fluid but suffers respiratory obstruction or asphyxia (10% to 15% of patients)
• "wet" - the victim aspirates fluid and suffers from asphyxia or secondary changes due to fluid aspiration (about 85% of patients)
• secondary - the victim suffers recurrence of respiratory distress (usually aspiration pneumonia or pulmonary edema) within minutes or 1 to 2 days after a near-drowning incident.

Causes

Near drowning can occur in deep or shallow water. Infants who are old enough to sit up on their own may not be able to pull themselves up if they slip under the water even in something as shallow as a bathtub. Near drowning can also occur if the child is hurt in the water, such as by a head or spinal injury caused by diving into shallow water. When anyone remains under water for too long, the larynx relaxes and lets water enter the lungs, which means the lungs can't function normally and transfer oxygen to the blood. The person loses consciousness and, eventually, the lungs collapse. Being deprived of oxygen for too long damages the body's major organs. However, if a child is submerged in cold water, a natural reflex slows the heartbeat and redirects blood flow to the heart and brain, where it is needed most. As body temperature goes down, the body tissues need less oxygen. This is a key factor in survival.

Signs and symptoms

• pale, cool skin
• absent, rapid or laboured respirations
• decreased level of consciousness
• coughing
• abdominal distention
• restlessness
• cyanosis (bluish color)
• vomiting

Diagnosis

Diagnosis relies on a physical examination of the victim and on a wide range of tests and other procedures. Blood is taken to measure oxygen levels and for many other purposes. Pulse oximetry, another way of assessing oxygen levels, involves attaching a device called a pulse oximeter to the patient's finger. An electrocardiograph is used to monitor heart activity. X rays can detect head and neck injuries and excess tissue fluid ( edema ) in the lungs.

Treatment

• Begin emergency treatment with cardiopulmonary resuscitation (CPR) and administration of 100% oxygen.
• Stabilize the patient's neck in case he has a cervical injury.
• When the patient arrives at the facility, assess for a patent airway. Establish one if necessary.
• Continue CPR, intubate the patient, and provide respiratory assistance such as mechanical ventilation with positive end-expiratory pressure if needed.
• Assess ABG and pulse oximetry values.
• If the patient's abdomen is distended, insert a nasogastric tube. (Intubate the patient first if he's unconscious.)
• Start I.V. lines; insert an indwelling urinary catheter.
• Give medications as necessary. Much controversy exists about the benefits of drug treatment of near-drowning victims. However, such treatment may include sodium bicarbonate for acidosis, corticosteroids for cerebral edema, antibiotics to prevent infections, and bronchodilators to ease bronchospasms.

Prevention

• Avoid drinking alcohol whenever swimming or boating.
• Observe water safety rules.
• Take a water safety course.
• Drowning can occur in any container of water. Do not leave any standing water (in empty basins, buckets, ice chests, kiddy pools, or bathtubs). Secure the toilet seat cover with a child safety device.
• Fence all pools and spas. Secure all the doors to the outside, and install pool and door alarms.
• If your child is missing, check the pool immediately.