Surgeon re-engineers way to rebuild babies' skulls

Most medical breakthroughs come after years, or even decades, of experiments in high-tech laboratories or academic research centers. But every so often, they are born at the hands of experienced physicians simply rethinking how they do things.

That's what happened last fall when Dr. Robert Wood, a pediatric craniofacial and plastic surgeon at Gillette Children's Specialty Healthcare in St. Paul, decided that something had to be done to reduce the rate of blood transfusions in babies undergoing surgery to correct a birth defect known as craniosynostosis.

The condition, in which the bones of the skull fuse together prematurely, is found in about one of every 2,000 live births. Left alone, it results in misshapen skulls, developmental delays and, sometimes, death. Surgery is the only way to correct it. In some cases, ones done early enough, surgeons can use a procedure known as minimally invasive surgery. But more commonly it requires making a wavy cut into the scalp and peeling back the skin so the bones of the skull can be excised and reshaped.

Wood is one of the most experienced physicians in the United States who perform the complicated procedure known as cranial vault expansion surgery. He said he decided to rethink how it's done after he and his colleagues were discussing blood conservation techniques at a professional meeting in September.

Transfusions are required in more than nine out of 10 craniosynostosis surgeries, according to the medical literature — a rate that matched his own experience, Wood said.

But transfusions themselves can cause problems.

Although the nation's blood supply is very safe from most infectious diseases, transfusion can introduce the possibility of post-surgery infections, fevers or even allergic reactions to the blood — to say nothing of the emotional toll transfusions exact on family members. They can also add to the cost of a procedure — an expense that sometimes falls partly to families with the expansion of high-deductible insurance policies.

Last fall, Wood decided to re-engineer the procedure to implement every reasonable method for conserving blood. He and his team gave the babies erythropoietin and iron for several weeks before surgery to control red blood cell production. Immediately before surgery they gave the babies tranexamic acid, which is commonly used to control blood loss during operations. They gave them a saline solution so that when they bleed, they lose diluted blood. They infiltrated their scalp with lidocaine, an anesthetic, and epinephrine, a hormone commonly called adrenaline, to constrict the blood vessels in the scalp. And they used a $400 disposable PEAK PlasmaBlade, made by Medtronic, which uses radiofrequencies to cauterize the blood as it cuts.

In the first group of 20 cases, the infusion rate dropped to 50 percent from 90 percent, Wood said. Half of the babies required no blood at all. "Going forward it looks like it's going to be about 75 percent," he said.

A crucial factor, Wood said, is the speed with which his team can complete the procedure. "The biggest operation we do … takes me under two hours. Elsewhere it would be four or six hours. That makes a huge difference because if you have a child's head open, even if you're not doing anything, there's passive blood loss."

About half of all craniosynostosis cases occur when bones fuse along the sagittal suture that runs from the forehead to the back of the skull. Wood says he's got those surgeries down to about 45 minutes.

Wood credits "resorbable materials" for increasing the speed of the surgeries. The reshaped bones are riveted in place using materials that dissolve over time, a major advance over the titanium plates and screws used until about a decade ago, he said. The rivets can be set quickly with an ultrasonic device.

Dr. Edward Ahn, a pediatric neurosurgeon at Johns Hopkins Hospital in Baltimore, said the longer a baby is on the operating table, the greater the risk of bleeding and contamination. After a reporter described Wood's revised methods, he said, "I think it sounds like a valiant effort" to solve an intractable problem with transfusions.

In addition to the health benefits, Ahn said, avoiding transfusions "absolutely" would save money.

Johns Hopkins offers minimally invasive surgery for craniosynostosis, which also avoids transfusions. But it must be done before the child is 3 months old and then the babies must wear a "molding helmet'' for a year. Wood said he fears that wearing a molding helmet may harm a child's cognitive development. In addition, he said, the procedure can be risky: If an artery is nicked during the surgery, "the child is dead,'' because there's no way to repair the damage quickly enough.

"I've never had a death in my career — ever,'' Wood said.

Dr. Suzanne Pauly, a family practitioner at North Memorial Health Care, opted for cranial vault expansion surgery for her son Michael after speaking with Wood. She said she'd never had a patient with craniosynostosis and had no family experience with the disorder until her son was born in August.

"When you know the gist of what they're going to do, it's kind of scary," she added.

Pauly said that before the procedure, Wood cautioned her that Michael likely would need a transfusion and drainage tubes in his head for a couple of days after the surgery.

"And then he came out of the OR [operating room] and hadn't needed a transfusion and he didn't have drainage tubes and we're like, 'It's amazing!' " she said. "He had his surgery on a Wednesday and went home on Saturday morning."

Dan Browning • 612-673-4493