Thank you for the query.
Bile sludge if gives no symptoms is not and indication for surgery. So if your husband does not suffer from stomach aches, especially after a meal, nausea
removal is not necessary. However it is advisable to have abdominal ultrasound
repeated from time to time (every year) as such sludge can lead to gallstones.
Bile sludge is mostly composed of cholesterol
crystals and calcium salts. The cause of it can be fatty diet. So it is advisable to reduce fatty foods.
Hope this will help.