1. DROWNING

2. INTRODUCTION
Primary respiratory impairment due to submersion in liquid medium
Outcome may be immediate death, delayed death or morbidity or life without morbidity

3. DEFINITIONS Drowning : Death by suffocation in a liquid medium.
Near drowning: Immersion seeking medical attention in which the patient survives for atleast 24 hours.
Wet drowning: Water in the lung due to aspiration
Dry drowning: Dry lungs due to laryngospasm

4. PATHOPHYSIOLOGY Laryngospasm Increased Left ventricular afterload
Systemic hypoxemia & acidosis
Cardiac depression
Apnoea
Alveolar hypoxia and hypercapnia
Laryngospasm
Increased Left ventricular afterload
Aspiration of water
ARDS & altered surfactant
Pulmonary edema

5. ASPIRATION Aspiration of 1-3ml/kg liquid causes deleterious effects
Fresh water enters microcirculation and destroys surfactant.
Atelectasis, decreased compliance and V/Q mismatching
Salt water causes exudation of protein rich fluid in the alveoli, alveolocapillary memb. damage and shunting
Aspirated fluid can cause pulmonary vasoconstriction and hypertension.

6. MULTI ORGAN FAILURE Hypoxemia and acidosis will depress the myocardium
VF can occur in near drowning in very cold water.
Hepatic and renal failure can occur.
DIC also can develop.

7. OTHER SEQUELAE
Direct injury to the head and neck can also cause brain damage.
Sometimes, aspiration of sand, silt, vomitus can obstruct bronchi causing bronchospasm, pneumonia and abscess
Rhabdomyolysis and acute tubular necrosis

8. COMORBID CONDITIONS Seizures Myocardial infarction Diabetes
Hypoglycemia
Suicidal tendencies
Neurological illness

9. INVESTIGATIONS CBC, RFT, ABG, pulse oximetry ECG
X ray chest, CT brain, X ray or CT cervical spine
Blood alcohol
Urine toxicology screen for the drugs

10. PREHOSPITAL CARE
Remove the victim from the water in prone position after ruling out the neck injury
No need to give compressions for the removal of water, as they are not proven to remove the fluid and delay the CPR.
Start CPR, if needed.
Begin rewarming. Remove the cloth immediately.
Shift the patient to the hospital as early as possible
Give adequate support to the neck

11. IN HOSPITAL CARE
Put NG tube to aspirate the gastric contents before intubation.
Endotracheal intubation.
Rewarming
Correction of acid base disturbances and electrolytes
Treating the underlying medical illness.

12. ENDOTRACHEAL INTUBATION
Intubation and mechanical ventilatory support :
Failure of trial with non invasive ventilation with Bilevel positive airway pressure ventilation in conscious victims
A-a gradient of > 60-80mmHg
PaCo2 > 45mmHg
Altered level of consciousness and not able to maintain the airway
High PEEP will help to remove the water from the lungs ( 4 cmH2O to 14 cmH2O)

13. REWARMING Wrap the patient with warm blankets.
Give warm fluids through nasogastric tube.
We can give warm(40 C) fluids through IV and bladder lavage to increase the core temperature.
Other measures like extracorporeal blood warming and open heart massage also have been tried.

14. OTHER MEASURES Treat the underlying medical illness
Treat other conditions like pneumonia and multiorgan dysfunction
Do not abandon the resuscitation until the body temperature reaches 30C
Attempt central venous access cautiously as it may stimulate the hypothermic atrium causing dysrhythmias.