April 2009 marked the opening of the new 20-bed Cardiovascular Intensive Care Unit (CVICU) at Packard Children’s Hospital—one of the largest facilities in the western United States dedicated to the care of critically ill pediatric heart patients.
“We’re often at 100-percent capacity,” says Stephen J. Roth, MD, MPH, the James Baxter and Yvonne Craig Wood Director of the CVICU. “Right now, we’re on pace to admit more than 650 patients this year.”
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Stephen J. Roth, MD, MPH
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The unit has been carefully designed to provide a welcoming environment for anxious patients and families. The expanded facility is spacious and flooded with natural light. An outdoor patio is accessible around the clock, as are sleeping rooms and a kitchen and bathroom for family members who wish to remain close to their child.
Social workers are available to help relatives find local hotels, food, and transportation. And family members are encouraged to work closely with the CVICU medical team, which includes eight attending physicians trained in pediatric cardiology and/or critical care medicine and 110 nurses.
“The majority of our patients have a nurse at their bedside every minute,” says Roth, associate professor of pediatrics at Stanford. “That is the very essence of intensive care.”
Studies show that critically ill children with heart disease often have better outcomes when cared for in a pediatric CVICU. “There are many children with cardiac problems who need intensive care, but in the past we didn’t have the capacity to bring them into our unit,” Roth says. “A tremendous advantage of having 20 beds is that we now have room to admit both medical and surgical patients.”
One example is heart transplantation. Patients who receive a new heart are cared for early after surgery in the CVICU. But some children with severe heart failure now come to the CVICU to prepare for a procedure known as a “bridge to transplantation,” in which a mechanical pump—usually a left ventricular assist device, or LVAD—is surgically implanted until a donor heart can be obtained.
“We implanted eight LVADs last year—by far the most we’ve ever done,” says David N. Rosenthal, MD, director of the Center’s Pediatric Heart Failure Program. “All eight went on to have successful transplants.”
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David N. Rosenthal, MD, directs the Pediatric Heart Failure Program.
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LVADs were actually designed for adults with heart failure, and not for small children. “In adults, the left ventricle tends to fail,” points out Rosenthal, associate professor of pediatrics. “But in children, it’s often the right ventricle, so the LVAD has to be adapted for a ventricle it wasn’t built for.”
In the 1990s, a German company developed the Berlin Heart, one of the first ventricular assist devices designed specifically for small children with heart failure. In 2004, 5-month-old Miles Coulson of Dixon, Calif., became the youngest child in the United States to be successfully bridged on the Berlin Heart. Since then, other Packard patients have received similar implants, and several are now participating in the first nationwide clinical trial of the device.
“Bridge to transplantation is the best we can do today,” Rosenthal says. “But when the technology improves, we may be able to use this kind of device to keep our patients stable for 20 years instead of just keeping them alive long enough to get a transplant.”
“We touch the lives of many of these children, not only the surgical ones,” says Chandra Ramamoorthy, MD, director of pediatric cardiac anesthesia at Packard. “Each year, we do about 500 operations and another 1,200 procedures, such as catheterizations, MRIs, and CT scans, where the child must remain still for a long time. Without anesthesia those would be impossible to achieve.”
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Chandra Ramamoorthy, MD
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LVAD implants, heart transplantations, and other cardiac procedures in children also require anesthesia. But anesthetizing or sedating a child, particularly one with heart disease, carries an increased risk of cardiac arrest that could lead to neurological damage, says Ramamoorthy, professor of anesthesia at Stanford.
Open-heart surgeries are particularly challenging. During the operation, the heart is stopped, and the child is placed on a heart-lung bypass machine that pumps oxygenated blood into the body until the surgery is complete. Brain injury can occur if oxygen levels are too low or from prolonged exposure to anesthesia medications.
Under Ramamoorthy’s leadership, the Children’s Heart Center has adopted novel techniques to reduce the risk of brain damage. “We monitor the brain during surgery to ensure that adequate amounts of oxygen are being delivered,” she explains. To further minimize risk, the patient’s body temperature is reduced while on the heart-lung machine by as much as 16 degrees Fahrenheit. This lowers the child’s metabolism rate, allowing the brain to function with less oxygen during surgery.
The post-operative period poses additional challenges. Prolonged administration of sedation and pain medications can lead to addiction, with profound effects on a child’s brain. So Ramamoorthy and her colleagues offer acupuncture, massage, and other holistic therapies to control pain and reduce anxiety, reducing the amount of pain medications a child may need.
The consequences of prolonged anesthetic exposure on the developing brain are also of concern. Recent studies conducted by Lisa Wise-Faberowski, MD, assistant professor of pediatric cardiac anesthesia, suggest that all anesthetics are not equal in their effects on a child’s brain. Her ongoing research focuses on using nuclear magnetic resonance spectroscopy to detect “good” versus “bad” proteins in the blood and brain after exposure to anesthesia medications.
“We don’t yet fully understand the long-term effects of sedation and anesthesia on the developing brain,” Ramamoorthy points out. “We want the best outcomes for the hearts and minds of the children we take care of, and are focusing our research in this area.”