"The wall of her house fell on her during the earthquake," says Dr. Bikesh Khambu, a resident neurosurgeon at the hospital.
An hour later, she receives a craniotomy in a makeshift operating room. Dr. Sanjay Gupta, a practicing neurosurgeon and CNN's chief medical correspondent, has scrubbed in at the request of a Nepalese medical team to help with the operation.
The conditions are less than ideal. Gupta washes up using sterile water and iodine poured from a bottle rather than hot water from a scrub sink. Instead of electric drills, he relies on saws of the variety usually only used in war zones and natural disasters due to the lack of electricity.
Despite the suboptimal conditions, the operation is a success, and her prognosis is good, Gupta says. It might not look it, but Sandhya is one of the lucky ones.
Thousands were killed when a devastating earthquake rocked Nepal
on Saturday. More thousands were injured, many of whom have flooded the capital's overstretched hospitals.
"I've seen a lot of situations around the world, and this is as bad as I've ever seen it," Gupta says.
"They need more resources, they need more personnel here right now, and they're expecting many more patients as these rescue operations go on.
"They're barely able to keep up right now. It's part of the reason they asked me (to help); I think they're asking anybody to try to pitch in."
'Everyone is scared to be here'
Bir Hospital, a government facility, is one of the busiest in Kathmandu.
Its inpatient wing, now scarred with cracks, was abandoned after big aftershocks Sunday, and doctors have scrambled to accommodate the influx of victims.
More than 4,300 were killed in Nepal by the 7.8-magnitude
quake, the strongest to hit the region in more than 80 years. More than 8,000 were reported to have been injured, but officials fear that number will be much higher once information emerges from remote areas.
Many of the wounded are now across the road from the hospital at the Nepal Army Pavilion, a huge open space in central Kathmandu, and tarps have been erected at the front of the hospital for people to have shelter.
Patients are housed here alongside other local residents who have fled their homes, finding shelter under tents.
"You should have been here yesterday. The building was shaking, and we all had to run out across the road," neurosurgeon Paresh Mani Shrestha says.
"Everyone is scared to be there. We evacuated the patients; no one wants to go there to work."
Hospital's early triage: 'Dead or alive'
Bir Hospital is a chaotic scene Monday as ambulances race in discharging new admissions, patients wail on stretchers in the lobby and distraught family members mill about.
"We have about 150 patients, but more are pouring in because the rescue is just happening," Shrestha says.
"When it happened on Saturday, all we could do was go 'dead or alive' -- that was the only triage we could do."
He says they received about 80 patients from Dharahara, the historic nine-story tower destroyed in the quake.
"There was nothing coming in yesterday," Shrestha says. But now the rescue is underway, and patients are arriving at Bir from less-equipped satellite hospitals.
Among them is a Western woman in a wheelchair, her arm in an improvised splint of branches. She comes from Langtang, north of Kathmandu, where reports are arriving of immense devastation.
Doctors are seeing patients with head injuries, pelvic and lower and upper limb fractures, Shrestha says.
Aid is on the way, but will it be enough?
Hospitals were running short on supplies despite international efforts to rush in aid
. Numerous aid groups and at least 16 nations rushed aid and workers to Nepal, with more on the way.
And although the surgeons at Bir Hospital were able to save the life of young Sandhya, international aid agencies have warned that other children may not be so lucky.
UNICEF, the U.N. children's agency, said Sunday that nearly 1 million Nepalese children urgently need assistance.
But some aid flights were delayed over the weekend due to aftershocks, leading to fears that many more may die before they get the help they desperately need.