i think it`s safer to do endoscopy once a jear to check out the mucosa of the distal esophagus, and, in case of Barrett, to do a mucosectomy...i personally try to avoid to do a sleeve gastrcetomy in case of symptomatic esophagitis

In my opinion any organ that is going to be surgically treated should be previously examined. So, it makes necessary to perform an upper endoscopy to rule out conditions not only of the esophagus, but of the stomach. On the other hand, sleeve gastrectomy by reducing gastric volume allows rapid  filling  the stomach, increasing its intraluminal pressure and if the mechanisms of the lower esophageal sphincter are not adequate, reflux occurs with the possibility that complications could occur after a while. I will try to avoid sleeve gastrectomy if there is any esophageal disease.

I agree with the above researchers.All Bariatrc proceedures ideally should have preop upper Gi endoscopy.If esophagitis is present better go for an alternative to sleeve.If already sleeve was done, i would consider yearly if no symptoms.If symptomatic needs Impedence manometry and endoscopic sretta or Lap cruroplasty.

Recent Gagner's study showed 31% symptomatic reflux in sleeve patients after 8 years.

Surg Obes relat disease;2017:13(7):1110-1115,.This study is authored by Gagner.

as such and from other studies, sleeve can be dangerous operation associated with 

repeated lower oesophageal injury by acid reflux on long term and that could predispose to cancer. 

So gastroscopy is indicated as preop test and patient should be consulted for the effect of reflux and long term findings and outcome after sleeve gadtrectomy to make an informed consent.

YES, IT´S MANDATORY, WITHOUT ANY dude make  gastroscopy.

The intraluminal pression in sleeve gastrectomy is too hight and this would be dangerorus for reflux

Yes indeed. You must do a complete upper endoscopy with several biopsies from the esophagus and the stomach and also to see the status of H. Pylori infection