Gold standard surgical procedure for prevention of aspiration is -
Aspiration is the passage of foreign material beyond the vocal cords:

The larynx has 3 distinct functions – respiration, phonation and airway protection. Dysfunction of larynx can lead to aspiration.
The primary goal of treatment of aspiration is to separate the upper digestive tract from the upper respiratory tract for a short period of time or in some cases, permanently.
There are 3 broad categories of treatment.

Temporary/Adjunct Treatments

Medical Therapy – in the form of antibiotics is important to prevent aspiration pneumonia.
It is important to make the patient NPO, to avoid further aspiration and to find an alternate feeding route to maintain the patients nutritional status. A nasogastric tube (feeding gastostomy/jejunostomy) is commonly placed, but this may actually increase the aspiration reflux by making the lower esophageal and upper esophageal sphincters incompetent.

But Still
“Tubal feeding (either by nasogastric tube or gastrostomy) however is often unavoidable.” – Scotts Brown 7/e, vol 1 p 1278

Here it is important to note that feeding Gastrostotomy / jejunostomy are not the gold standard methods of preventing aspiration but rather are done to maintain the nutritional status of patient and prevent further aspiration. In fact according to most texts

– they are a common cause of aspiration.

Vocal cord medialization (by injecting Gel foam) is useful in unilateral paralysis.This is helpful but is rarely curative, if there is a serious aspiration problem.
Tracheostomy will often make aspiration worse by preventing laryngeal elevation on swallowing. It does however, allow easy access to the chest for suctioning. Even a cuffed tube doesn’t prevent aspiration as secretions pool above the cuff and the seal is never perfect” 

Scotts Brown 7/e, vol 1 p 1278
Definite – Reversible Procedures

Endolaryngeal stents: They function like a cork in the bottle. There job is to seal the glottis and therefore thay need to be used in conjunction with a tracheostomy tube. But they are not often used as they are effective only as a short term solution, plus there is risk of glottic stenosis.
Laryngotracheal separation: The procedure involves transecting the cervical trachea and bringing out the lower end as a permanent end stoma
According to Scotts Brown and Internet sites: It is the procedure of choice as it is reversible. But it has disadvantage of sacrificing voice.
Alternative procedure is Tracheoesophageal diversion but has higher complication rates.
Thyroplasty
Tracheostomy
Tracheal division and permanent tracheostomy
Feeding gastrostomy jejunostomy