Shawn Todd, who lives just outside of Mobile, Ala., thought she was having a routine partial hysterectomy.
For Sonya Melton of Birmingham, it was routine same-day gynecological surgery to treat uterine fibroids.
And for Kimberly McCalla, just 24, it was supposed to be a routine hysterectomy.
But none of the procedures turned out to be routine.
Todd and Melton wound up at what they believe was death's door, hospitalized for weeks from complications from their surgery involving the high-tech da Vinci robot.
McCalla suffered bleeding into her pelvis from a laceration to a main artery during a robotic-assisted hysterectomy, her father claims. She died 13 days after the initial surgery. Her father, who is suing Intuitive Surgical, claims she died "as the result of, among other things, injuries sustained by the use of the da Vinci surgical robot."
"Blood was flowing from her leg, from between her legs," her father, Gilmore McCalla, told CNBC. "And two nurses were there around her, catching the blood with a bottle."
Intuitive Surgical, which makes the da Vinci, declined to discuss their cases because of pending litigation.
Most robotic procedures take place without a hitch, but there are a growing number of complaints and lawsuits that allege complications and even deaths from the da Vinci surgery.
"The robot has a place in surgery," said Dr. Francois Blaudeau, a lawyer and practicing Alabama gynecologist who is serving as the lead plaintiffs' attorney on a slew of cases focused on da Vinci-related injuries.
CNBC.com's Da Vinci Debate series:
Part 1: Controversy Over Surgical Robotics Heats Up
Part 2: Patients Scarred After Robotic Surgery
Part 3: Counting the Problems of Robot-Assisted Surgery
Part 4: Marketing Is Key to Surgical Robot's Success
According to lawsuits, complaints, interviews with alleged victims, plaintiff attorneys and an FDA database, many of the reported injuries during robotic surgery appear to be burns and other heat-related damage to intestines, ureter, bowels and other organs.
The injuries, claims Blaudeau—who represents Todd and Melton—are sometimes not apparent for days after the initial procedure.
Blaudeau attributes many of the burns to the company's use of monopolar energy, which he says can cause sparks that leave residual damage.
Intuitive told CNBC that monopolar energy instruments "are not unique to robotic surgery," adding that it "is confident that the da Vinci surgical system deploys monopolar energy in a safe and effective way when used as indicated."
It appears Intuitive has attempted to allay the situation by introducing new tip covers. CNBC has obtained internal documents that show in May 2012, without explanation, Intuitive introduced a replacement to its "tip cover accessory" for da Vinci's monopolar instruments. The "important product notification" asks hospitals "to begin using" the new tip cover "immediately." The company also requested hospitals acknowledge receipt of the letter and return the older model for credit.
In an emailed response, Intuitive said: "In any type of surgery, there are rare instances in which insulation may be damaged during use. Intuitive Surgical invented a new bonding process that allowed production of a more robust tip cover. The original tip cover was not deemed defective; however, the company replaced existing customer stock with the new tip covers when they became available. The new tip covers were cleared by the FDA in 2011. Tip covers are replaced after every procedure."
However, the replacement tip cover does not appear to be entirely effective at stopping possible problems with sparks or electrical arcing from its monopolar energy. A video of da Vinci machine by Dr. Younes Bakri, director of gynecologic oncology at West Virginia University and a robotic surgeon, explicitly shows electrical arcing from the new cover. Contacted by CNBC, the surgeon asserted that the new tip still produces arcing, which he and other critics say can burn tissue.
Watch video: Da Vinci Surgical Robot in Action (Warning: Note graphic contents.)
In response, Intuitive told CNBC:
"Based on extensive review of the video, we are certain that what is being observed is not an instrument or tip cover failure. The electrocautery energy is coming from the scissor blade as designed. The arcing seen in this video would occur in a laparoscopic instrument the same way if operated in this manner."
With the number of procedures nearing a half a million last year, da Vinci remains a popular surgical option—an option Gillmore Micalla wished his daughter had not taken. "I try to put it behind me," he said. "But I can't get past it. This is a child. She had a bright future ahead of her."
(Related Article: Robotic Surgery: Growing Sales, but Growing Concerns)
—By CNBC's Herb Greenberg; Follow him on Twitter:@herbgreenberg and Google
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