Bandwidth: How much is enough?

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So, how much bandwidth does it take to ensure adequate capacity along a network line throughout a facility so that voluminous medical images and files have enough room to travel at near blink-speed with other non-patient-related data?

Ask healthcare IT people and their response more of than likely will be: How much can I get? And how much will it cost?

Right now, healthcare providers talk in gigabytes when they discuss bandwidth requirements.



CALCULATING BANDWIDTH

There are many factors to take into consideration when determining adequate bandwidth, given the amount of data traffic on a healthcare provider's network.

"It's not a question of taking the number of images [facilities] plan to transmit and the size of the images, multiply those out, divide by the time in a day and figure out the size of pipe needed," says Janet Rogers, COO of bandwidth and managed services provider ANET Internet Solutions. "That would assume that utilization is spread evenly throughout the day."

Demand, of course, does not occur at a constant rate. The network will have greater traffic flow during the work day than in the evening or overnight. The question then becomes how to handle the peaks as efficiently as possible?

"One way to handle the peaks is to build a pipe that is big enough to absorb the biggest possible peak," Rogers adds. "Then you have to decide if you have the budget to do that, knowing that the rest of the time the pipe is 95 percent unused."


PEAKS AND VALLEYS

Health First has three main hospitals in Florida - Cape Canaveral Hospital in Cocoa Beach; Holmes Regional Medical Center in Melbourne; and Palm Bay Community Hospital - as well as some 40 outlying clinics and medical imaging centers.

"The challenge we have run into with PACS and imaging is that, because we have multiple hospitals, bandwidth could be an issue," says Health First PACS Administrator Frank Waszmer.

Health First also plans to break ground on a new facility in 2005 and build a state-of-the-art heart institute attached to the main trauma center at Holmes.

With the help of PACS vendors, Health First used a formula to estimate the workload per modality, as well as the historical image and file volume at each facility for each modality. IT personnel also anticipated how much storage space the facilities would need per year and how that amount would increase over time. (See chart on page 68.)

"Once we figured out each facility and what the load and daily demand would be on the network and scaled that to future use, we went back and addressed the infrastructure," adds Waszmer.

Health First chose Heartlab as its cardiology PACS provider and McKesson Corp. for its radiology PACS. The radiology PACS installation currently is underway. Starting this October, HealthFirst will begin to upgrade the channel to 2.5 gigabytes.

"When we bring in our PACS and roll out the equipment in June, our image volume with the new [multislice] CTs will skyrocket," says Waszmer. "Do we need gigabytes to the desktop? No, but from the CTs, if we have a one-gigabyte uplink switch, we can move these images around the network fairly rapidly."

Over the last two years, Health First has invested approximately $2 million in network infrastructure projects.

"Next year, I am sure we'll spend at least another $500,000 to $750,000 on the same type of costs," Waszmer says. "This initiative was to bring a 100-megabyte minimum [capacity] to the desktop of every user within Health First, as well as taking our core infrastructure away from ATM (asynchronous transfer mode) switches to Ethernet switches. It benefited our whole environment by upgrading our infrastructure."


'BLINK SPEED'

North Bronx Healthcare Network is part of the New York City Health and Hospital Corp., one of the largest municipal health systems in the United States. North Bronx - through its two facilities, Jacobi Medical Center and North Central Bronx Hospital - and serves some 1.2 million people in its coverage area. With that amount of current volume and expected growth, North Bronx was concerned about its current and future bandwidth needs.

The system made the leap last year from a 10-megabyte network to a 10-gigabyte core. The upgrade was not inexpensive - requiring an investment of $3.5 million for the necessary IT equipment, plus additional money for installation and redundant fiber optic cable. The system started its upgrade in July 2003 and rolled out all the equipment by last October.

The gain in efficiency with the enhanced capacity was dramatic, as providers' access to images and other patient information became almost instantaneous.

"Throughout the organization, we were facing delays of up to five or six seconds in bringing up images and accessing other pieces of information from various systems, because we gave our PACS a very high level of service on the imaging side," says North Bronx CIO Daniel Morreale. "We saw that delay drop to blink-speed, so we are very happy with that."

North Bronx also went from 92 percent capacity on its previous network to less than 3 percent capacity on its current configuration. Included on the IT network are functions such as order entry, results reporting, speech recognition and dictating, and security systems. Everything, Morreale adds, is "network-driven."

"There is plenty of room for growth and we'll need it," he continues. "The images that are coming with cardiac and ultrasound start getting into the range of one gigabyte or 1.5 gigabyte per study. We'll need the elbow space."

With its current capacity, North Bronx expects to get five years of use out of its 10-gigabyte network. "In five years, we will probably see a whole new generation of network connectivity that we'll have to look at."


RADIOLOGY'S IMPACT

Wyoming Valley Health System is a 416-bed facility in Kingston, Pa., which performs some 150,000 procedures per year, excluding mammography. That volume translates into 275 million images, says CIO Chris Galenda.

"There is no other area of our business that consumes the bandwidth that radiology does," says Jim Rakshys, Wyoming's director of advanced technology.

The hospital upgraded its network about three years ago, installing an Ethernet over fiber optic cable. The full gigabyte network also provides a minimum of 100 megabytes of capacity to desktop workstations. Even at peak-demand times during the day, Wyoming is using less than 20 percent of the system's capacity with its gigabyte network.

"We are not losing any information; we are not getting any complaints from our radiologists or other referring physicians pulling up images remotely or on-site," says Galenda. "No one is complaining that the system is slow."

Galenda recommends at least a gigabyte of bandwidth to support traffic on a network. That amount also is expected to accommodate the facility's coming addition of digital mammography images to the information pipeline.

"If we were at 100 megs as we were three years ago," she adds, "it would have been a total disaster."

The next step for Wyoming would be a 10-gigabyte network, but Galenda says that "is years off." Still, she expects Wyoming to make the leap without "a major change to add a gigabyte infrastructure to the modalities. We can do it without any great investment."

Wyoming made a $3.5 million investment over several years to install its PACS and acquire and implement related IT infrastructure to get its network to its current configuration.


COSTS AND CHALLENGES

T1 lines have been the connection of choice for healthcare providers for several years now; and T3 lines offer 28 times the bandwidth available on a T1 line.

On a per unit basis, ANET's Rogers says the cost of bandwidth has been "in a freefall over the last couple of years - which is really good news for anybody who is consuming bandwidth in a big way." The recession in the telecommunications industry has been the prime reason for the decline.

While a healthcare facility can connect to a T1 line for $500 to $700 a month or a DSL line for less than $100 a month, if the provider needs a 10 megabyte T3 or 10-megabyte fiber optic Ethernet connection, location may become an issue.

"In today's market, you fall off the cliff after T1 speed. In most environments, there is no affordable way to obtain that," Rogers says. "Our challenge is how to serve what I think is the next huge growth segment in the medical community."

In addition, a T1 line may be adequate for a small practice, where the information is largely text-based, but Rogers believes that eventually T1 lines will become obsolete as the demand for more advanced medical imaging technology advances.

"As this telemedicine initiative continues, grows and matures, we will see that the T1 line in these satellite organizations isn't good enough, because you're not going to see the full motion and animation of a patient's MR image - especially if someone else is using the line at the same time," she says. "You will not be able to quickly download a variety of high-resolution images, especially if other information is being uploaded at the same time."

ANET currently is working with Perry Medical Center in Princeton, Ill., which serves a rural community of approximately 8,000 people. Perry requested a 100-megabyte line to exchange data with larger hospitals in the Chicago area, around the country and around the world. Perry also serves as the hub for other smaller hospitals and clinics in the Princeton area.