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One of the many resource shortfalls of Galactica's ongoing logistical nightmare is a shortage of medical personnel. Doctor Sherman Cottle is the only trained physician on board, supplemented by a handful of medics. As a result, Ishay has been required to step up to perform medical procedures she wouldn't normally be expected to perform.
Immediately after the attempted assassination of commanding officer William Adama by Sharon "Boomer" Valerii, and with the absence of Doctor Cottle from Galactica during her isolation from the rest of the Fleet, Commander Adama's life is left in the hands of Galactica's paramedics.
Despite never having performed an operation in her life, Ishay's emergency thoracic surgery stabilizes Adama's condition until Doctor Cottle returns, who, with Ishay's assistance, stops the commander's internal bleeding (TRS: "Fragged").
Ishay assists Cottle with a sonagram to show Caprica-Six and Colonel Tigh their unborn child, pointing out the elements of the sonagram to Tigh. When Tigh realizes what he is looking at is the small form of his own baby, he feels overwhelmed a little at the sight, and asks for a drink. Cottle offers a cigarette instead to Tigh as he lights one for himself, to Ishay's chagrin. While she is going to get a fetal monitor for the child, She passes Felix Gaeta, in to get his prosthetic leg cared for. Gaeta is annoyed at all the attention that the Cylons are getting, and Ishay offers her support, which further annoyed the lieutenant.
Ishay is present when Dr. Cottle informs Galen Tyrol that his son is suffering early renal failure but treatment should prevent a damaged kidney. The problems complicate when Tyrol reminds the medical team that his child is half-Cylon, but Ishay tries to tell Cottle to inform Tyrol of something important. Cottle dismisses Ishay and speaks with Tyrol privately, telling him that Nicholas is not actually his son (TRS: "A Disquiet Follows My Soul").
Following the Gaeta's Mutiny, Ishay is present assisting Cottle to perform surgery on Samuel T. Anders, who was badly injured in the mutiny. Following his brain surgery, Kara Thrace, Anders' wife, tried to talk to him, but Ishay said quite blantly that Anders was more or less comatose (TRS: "No Exit").
When Adama starts planning a rescue mission for Hera Agathon, Ishay discusses it with Cottle. Later she and Cottle are both among the volunteers, but while Cottle is sent back due to being too valuable, Ishay remains and became one of the people crewing Galactica on her final mission. (TRS: "Daybreak, Part I")
She is the chief medical adviser for the mission to The Colony to rescue Hera, and heads a group of volunteers as they tend to the wounded and the dead. Ishay tells Roslin to mark the dead with a black 'X' on their forehead in permanent marker. She is later seen giving out orders during the battle, tending to several dead and dying Marines. (TRS: "Daybreak, Part II")