Sara, if your mom is not going to be able to eat, there is the option of total parenteral nutrition.https://en.wikipedia.org/wiki/Parenteral_nutrition
This may or may not be advantageous depending on other factors, but if she has good performance status and decent vital signs it may be worth a try. People can live months or longer on TPN in some cases. Though there is a risk of infection or other serious issues, the certainty of starvation without eating would definitely make me want my wife to try this option if her SBO does not clear up.
From what I gather, TPN is not recommended if the patient is near end of life anyway, and often SBO if it is caused by malignancy (as opposed to adhesion) is an indicator of that.
DW Dx 7/15, 41 yo, st IV, 3+ liver mets: 11.3 cm, 7cm, 3cm. MSS.
KRAS, APC, SMAD4, TP53 mut.
7/15-10/15: FOLFOX+bev. x8
11/15-12/15: SIRT (Y90)
1/16: Toxic Hepatitis, chemo break
4/16: Liver resec. fail
5/16-7/16: FOLFIRI x6
8/16: Liver resec.
8/16-11/16: FOLFIRI x6
2/17: IMRT/Xeloda x25
6/17: CT: Progression. Peri, Lung, Liver mets. FOLFIRI x6
9/17: FOLFIRI+Bev x5.
11/17: CT: Stable. 5FU+bev. maintenance x5
1/18: Surgery for SBO due to internal hernia. 37 days in hospital.