Texas Mom Sues After Insurance Denies Claim and Daughter Dies of Appendicitis Isabella Tolentino, 6, died after appendix surgery on vacation in Caribbean.

Dec. 31, 2013 -- A Texas nurse and mother has sued her insurance company after her 6-year-old daughter died of a brain injury when appendicitis surgery allegedly went wrong while the family was on vacation in the Dominican Republic in 2012.

Marissett Tolentino alleges in a lawsuit filed Dec. 17 in Galveston County Court that Blue Cross Blue Shield of Texas denied her sick daughter Isabella a medical jet that they were entitled to under their policy, which led to surgery "being performed in substandard conditions" at a local hospital.

Isabella had her appendix surgically removed at a BCBSTX-authorized facility, Hospiten Bavaro in Punta Cana, but she never came out of the anesthesia and suffered a fatal brain injury, the lawsuit alleges.

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Eventually, the insurance company approved the medical jet and airlifted the little girl to Miami, but it was too late to save her, according to the lawsuit.

"They gave her the dosage equivalent of a 6-foot, 200-pound man. And she was intubated with an infant-sized tube instead of a toddler one. Not only was she drugged up on so much anesthesia, she wasn't breathing the right amount of oxygen," explained the lawyer for the Tolentinos, Mason Herring of Houston.

The wrong-sized breathing tube was discovered when Isabella was airlifted to Miami and the medical team aboard the jet found mucus clogging the tube, according to Herring.

Tolentino and her husband Francisco allege in their lawsuit that the insurance company was too cheap to initially approve the flight.

"I just thought, I've been paying all these premiums all these years and then when I really needed them, they wouldn't pay for an $18,000 flight," Tolentino told the Houston Chronicle, which first reported the story. "I have to deal with the daily struggles of losing my child over something so stupid -- them flying her home."

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The lawsuit alleges "lack of ordinary care proximately caused injury, which resulted in plaintiff's death."

The Tolentino family has charged BCBSTX with "gross negligence" and violation of the state's Deceptive Trade Practices Act. They are seeking unspecified damages for Isabella's physical pain and their own mental anguish.

When contacted by ABCNews.com, Louis Adams, a spokesman for Blue Cross-Blue Shield of Texas, would not discuss the case because it was "a matter of pending litigation."

The company has not yet filed a response to the court.

Hospiten Bavaro was not named in the lawsuit, but Tolentino "absolutely has not absolved the hospital," said her lawyer Herring.

"She can't sue in the U.S.," he said. "The Dominican Republic's civil system is very antiquated and very harsh to foreigners."

When asked for comment, hospital spokeswoman Jacki Mendes told ABCNews.com, "Unfortunately we do not provide medical information about our patients without their authorization."

The lawsuit alleges that the insurance company and Hospiten Bavaro didn't share with the family the complications of surgery and didn't get her help in time.

"I feel very guilty, like I made the wrong decision," Tolentino told the Chronicle. "I should have fought the insurance company harder. They don't care about what happens afterward. It's not their child."

"Blue Cross Blue Shield was aware of the severity of Isabella's condition, yet they knowingly delayed the process and placed administrative prerequisites above the urgency required to save Isabella's life," according to the lawsuit.

According to court papers, Isabella complained of sharp stomach pains on July 5, 2012. When she developed chills and a fever, the family asked for help a medical clinic at Dreams Palm Beach Resort, where they were staying.

Doctors there diagnosed appendicitis and sent her to Hospiten Bavaro, where immediate surgery was recommended, according to the lawsuit.

"Plaintiffs were not comfortable with the idea of subjecting their daughter to a procedure in a foreign hospital that may not meet the standards of professionalism and care of an American hospital," alleges the lawsuit, and asked that she be transferred to the United States.

Local doctors and the girl's own pediatrician advised that putting Isabella on a commercial flight would be too dangerous and recommended she be flown to the U.S. on a medical jet, according to the lawsuit.

Their claim was denied by BCBSTX, according to the family.

"...[I]n their opinion, the medical condition was not severe enough," alleges the lawsuit, and the insurance company "trusted [the] expertise" of its local in-network hospital.

"The denial of this service forced plaintiffs to have Isabella's surgery performed at Hospiten Bavaro," the lawsuit alleges.

The family says that Isabella did not wake up after surgery and was told she was "very unstable," according to the lawsuit. Doctors told them their daughter had vomited while unconscious and blood had come through the intubation.

Hospital staff told them the girl's oxygen levels were low but "not to worry," according to the lawsuit. The next morning Isabella's condition was critical, but the family said BCBSTX, which was aware of her state, made no effort to contact them or approve a jet until the end of the day.

"They insisted on delaying the transfer until a Hospiten doctor sent a report to the doctors in Miami, where Isabella's transfer would be," alleges the lawsuit. "Hospiten staff unreasonably delayed in sending this report and claimed to have difficulties communicating with Miami."

"BCBS was fully aware of the severity of Isabella's condition but still had not authorized the medical jet," the lawsuit alleges. The family also says "precious time was wasted" with delayed paperwork to the Miami hospital where Isabella was to be transferred.

They also allege that both Hospiten Bavaro and BCBSTX refused to authorize the transfer of their daughter until payment was made. Then a medical jet scheduled for 10 a.m. did not arrive until 2 p.m., according to the lawsuit.

Doctors in Miami discovered "brain damage resulting from the oxygen deprivation," according to the lawsuit. Isabella later went into seizures and died.

Tolentino's lawyer said that medical records sent to Miami revealed hospital errors.

"But parts of the story don't add up and don't make sense," said Herring. "We are trying to get to the bottom of that. ... Now, insurance companies are making the decisions about what is a life-threatening sickness or injury -- they are making medical decisions for people."

The family has set up a web page, the Prinsabella Mia Foundation, in memory of their daughter to help other children with brain injuries.