Whoosh!

A pneumatic tube carrier set off one recent Saturday from station 851, an inpatient unit at St. Jude Children’s Research Hospital. The carrier’s destination was the Pathology main lab. 

Tiffany Everett, a pediatric oncology nurse, sent the carrier. She didn’t know the routine specimen transfer was the 5 millionth transaction since the system’s 1997 installation.

In roughly two minutes, the carrier zipped 1,760 feet through a 6-inch metal conduit, reaching speeds of 25 feet per second (17 mph).

“It’s such a vital system,” said Donna Patterson, director of Laboratory Operations in the Department of Pathology. “When it goes down, everybody’s walking specimens.”

The tube system is vital because it can efficiently and safely deliver specimens, blood products and medications to their destinations.

Downtime might affect care for St. Jude children facing life-threatening diseases.

“Downtime takes nurses away from the patients,” Patterson explained.

She works closely with the Department of Nursing, the system’s primary user, and Pharmaceutical Services, which is a close second.

Jerry McGovern, a supervisor in the Department of Facilities Operations and Maintenance with a special connection to St. Jude, works diligently to keep the system in good repair. He gets a lot of help from mechanics, including Dustin Chipman, Harold Carter and Aaron Shrives.

St. Jude’s pneumatic tube system sends its 5-millionth transaction.

Tube carrier: Press send

That Saturday, Everett followed the usual process to send the carrier. She swiped her ID badge, secured the specimen in a red, leak-resistant carrier (medications from Pharmacy go in green carriers; blood products from the Blood Bank in blue carriers). She placed the carrier in the dispatcher, chose the destination and pressed “send.”

“The system does the rest,” said Chipman, the lead tube system mechanic.

The use of air to move the carriers is a simple concept to grasp.

“It’s either blowing the carrier to you or vacuuming it from you,” McGovern said.

 At launch, the vacuum force sucks the carrier through the shoot to a transfer unit, “a rectangle metal box with a pipe that rotates around in a circle,” Chipman said.

When the carrier enters the transfer unit, it’s routed to one of the four or six other pipes available for transit. McGovern compares this part of the transfer unit to a railway switch diverting cars from one track to another.

The entire tube system consists of stations and zones.

“In a zone, the system can only move one tube at a time,” McGovern said. Users, however, don’t have to wait long for a transaction to be complete. “It keeps things moving quickly,” he added.

According to Patterson, it’s possible that a technician sitting in the specimen receipt area could hear Everett’s carrier approach the Pathology lab. In fact, many tubes converge on this area. “Our women’s restroom is next to the specimen receipt area,” she said. “You can hear the carriers through the ceiling.”

At the end of the line, Everett’s carrier dropped into a bin at the main clinical lab, station 251.

The art of tube system maintenance

McGovern and Chipman are more than familiar with the 2.5 miles of piping that wind through the interstitial and ceiling spaces of six St. Jude buildings (not to mention the brief underground stint to a building on the periphery of campus).

Nearly 250 carriers, tracked with radio-frequency identification or RFID sensors, move through the system. About 1,400 carriers are dispatched on an average day.

Of course, the system has to be kept in good working order. Transfer units, for example, require routine maintenance.

“You have to keep the chains greased and lubed,” Chipman said. “The chain is connected to that piece of pipe that rotates, and it’s connected to a motor.”

Shift engineers at the Central Energy Plant use software to monitor the tube system 24/7. They can see carriers in transit in real time on a grid. If a problem arises and an alarm sounds, they can radio Chipman or one of the other mechanics.

 “The main thing is to keep the system up and running with users unaware there’s a problem,” Chipman said.

Tube system uptime: A little better each day

McGovern is proud of the tube system’s 98% uptime. Yet, aiming for 100%, all the mechanics strive to do a little better each day.

As the father of a St. Jude Wilms tumor survivor, McGovern has a personal stake in this lofty goal.

“We’ll get up at 2 o’clock in the morning,” he said, referring to the relatively infrequent emergency calls the team receives to repair the tube system. He echoed Patterson’s concern about tube system downtime.

“It takes away from the patients,” he said.

Every day, McGovern and his team climb ladders, inspect parts and make needed repairs to contribute to the hospital’s mission of saving children. They help keep nurses near their patients and other clinical care staff at their posts.