Naogastric tube

Is there a possiblity that a nasogastric tube is inserted into the esophagus without reaching the stomach, yet aspirate less than pH5 can still be obtained, such as in a patient with GERD?
I recently wrote a paper related to enteral feeding tubes so I had a reference handy...This is from the Journal of Parenteral and Enteral Nutrition: Enteral Nutrition Practice Recommendationsquotes are from p. 23"The appearance and pH of aspirates from a feeding tube mayprovide useful clues to an enteral access device location.For example, fluid withdrawn from a tube that has perforatedinto the pleural space typically has a pale yellowserous appearance and a pH of 7 or higher, while fastinggastric fluid typically is clear and colorless or grassy greenwith a pH of 5 or less.12-16 However, appearance and pH ofaspirates are not sufficiently accurate to distinguishbetween gastric and bronchopulmonary placement.""It is difficult to obtain an aspirate from an enteralaccess device when the tip lies in the esophagus. On theoccasions when an aspirate can be obtained, it is likelyrefluxed gastric juice or swallowed saliva. Thus, observingthe aspirate's pH and appearance is of little or nobenefit in this situation. The auscultatory method alsocannot differentiate between the esophagus and stomach."Sorry for bad formatting but I have to get ready for work!link to document: http://pen.sagepub.com/content/early....full.pdf+html