Extremely premature babies whose lungs aren’t fully developed can be treated with lung surfactant harvested from cattle
Little Avery Hopp of Birtle, Man., recently celebrated her second birthday. Like most two-year olds, the occasion was marked with much love and celebration from her family and friends as another milestone in her young life was reached.
But unlike most other two-year-olds, for her parents, Haley Johnston and Tyrell Hopp, the celebration was a little sweeter and cherished just a little bit more. For this birthday, and all of her birthdays to follow, the day is a vivid reminder of the pure miracle of her life itself.
Avery was born prematurely on March 1, 2019, at just 27 weeks, two days.
What makes this story even more significant from an agricultural perspective is that a little-known contribution by the livestock sector played a vital role in saving Avery, and babies like her.
Despite the fact that it is now so commonly used in neonatal intensive care units (NICUs) across North America, yet is so unrecognized by the public at large, Avery’s parents were not even initially aware of its existence.
Avery, like most premature babies, received a treatment shortly after birth called bovine lipid extract surfactant (BLES), a unique substance made up of fats and proteins, which is found in the lungs. In other words, she was treated with lung surfactant harvested from a cow.
With a normal-term baby being born at about 40 weeks, 27 weeks gestation is considered very preterm. The good news is that according to statistics, fewer than one percent of babies are born this early. The even better news is that most babies (90 percent) who reach this stage of gestation do survive with no neurological problems, of which Avery is living proof.
Since the lungs are the last major organ to finish developing in an unborn fetus, a good majority of premature babies are born without sufficient surfactant in their lung tissues, which is crucial for breathing. Surfactant works as a lubricant in our lungs, which keeps the tiny alveoli (air sacs) from collapsing upon exhalation.
When a baby is born without this surfactant, it exacerbates their breathing process as they struggle to reinflate collapsed airways. This is called respiratory distress syndrome (RDS).
“Surfactant is a phospholipid produced by specialized cells in our lungs,” said Deb Fraser, a neonatal nurse practitioner working in the NICU at St. Boniface Hospital.
“The analogy that I like to use is that surfactant is like Teflon on a frying pan; it keeps things from sticking together. Alveoli are like balloons; they take effort to inflate the first time and, if they are wet inside, the walls stick together and it’s very difficult to inflate them.”
Enter the livestock industry.
Vigorous research into RDS was initiated as early as 1963 when the son of then U.S. president John F. Kennedy, was delivered at 35 weeks gestation and subsequently died at two days of age due to RDS. Trials began the very next year without much success. Then, in 1972, it was discovered by a researcher at the University of Western Ontario in London, Ont., Dr. Fred Possmayer, that lung surfactant could be successfully harvested from animals, including cattle and pigs.
He later teamed up with Dr. David Bjarneson and Dr. Harold Nigh to further investigate the potential for this product. They founded a company by the name of BLES Biochemicals Inc. and made it their life’s mission to manufacture and supply surfactant to save premature babies across Canada and eventually the world. The first infant treated with BLES in a trial back in 1983 proved to be a monumental breakthrough for the medical community.
Widespread use of animal-derived surfactant began in earnest following this discovery. Although BLES is one of many surfactants available, it is unique in that there is no generic form of this product; it is harvested solely from the lungs of cattle.
“There are now a number of animal-derived surfactants used to treat newborns and (they) come from both cow and pig lungs,” reported Fraser, who attends deliveries of high-risk newborn infants to determine the babies that would benefit from receiving the surfactant, and then administering it.
“In premature infants with RDS, animal-derived surfactant is given through a tube inserted into the trachea soon after birth to improve gas exchange and reduce the need for mechanical ventilation.”
Fraser definitely knows what she is talking about. She was raised on a farm near the community of Franklin, Man., and sees the value and importance of BLES and the contributions of the cattle industry for this special population of babies, first-hand, every day of her life.
She has been a neonatal nurse and nurse practitioner for 40 years and has written three textbooks, including one on respiratory care in premature infants.
“I have worked in the NICU for 40 years — both pre- and post-surfactant introduction,” said Fraser. “I have seen many changes over the years but can truly say that surfactant therapy is one of the most beneficial innovations that I have seen. The difference in the severity of lung disease is nothing short of miraculous. In premature infants, severe lung disease and the need for oxygen therapy and ventilation increases the risk of infections, damage to the developing brain and eyes and can greatly increase the length of stay in the hospital. The ability to give a therapy that so dramatically reduces the number of complications of prematurity greatly improves the lives of premature babies and their families.”
The company, BLES Biochemicals Inc., which harvests the white foam from cattle lungs, is based in London, Ont., and gets most of its supply from an abattoir owned by Cargill in Guelph, Ont.
The story of how they began this unique relationship is a story in and of itself. After a chance phone call in an attempt to locate a larger abattoir with access to a bigger source of raw product to satisfy the demand for their surfactant, Nigh stumbled upon a producer who himself had been a preemie, and the rest, as they say, is history.
“I harvest cow loogies for a living” is a strange thing to have on one’s resume, but such is the case for the team of foam extractors from BLES that frequent the slaughterhouse one day every week. They operate like a well-oiled machine; their presence approved by the Canadian Food Inspection Agency, they harvest straight from the source, which they have found to be the most efficient and effective. They arrive ahead of the day’s shift to unload their extraction equipment, and are the last ones to leave at the end of the day. They must perform their task quickly and methodically, having only 28 seconds per animal to collect the precious foam. The foam derived from one set of lungs can be used to treat two preemies. The BLES team is usually able to capture the foam from around 700 cattle of the approximate 1,500 head that are processed daily at the facility.
The foam is both hydrophilic and hydrophobic. It is harvested by washing the animal’s lungs at the time of slaughter. About 20 litres of salt water is injected into the lungs and the run off is captured; firstly, the water, capped off with the precious lung foam which sits on top of the water making it easy to extract. The foam is then broken down with solvents and machines to condense it and make it transportable. Back at the lab, it is then purified and processed into a safe state to be administered to preemies worldwide.
Science wouldn’t be science if it weren’t trying to come up with new and better ways to replicate nature to replace the surfactant with synthetic versions. None have been overly successful. One of the most recent attempts was a product called Surfaxin, which was developed in 2012, but was discontinued in 2015 because it was unable to compete with the animal-derived product.
“There have been a number of synthetic surfactants that have been used but, to date, none of them have produced the success that bovine surfactant has,” Fraser stated. “It seems that the ability to mimic the complex mixture of proteins and fats (found) in natural surfactant has so far eluded scientists.”
As reported by Nigh back at BLES, they face an increasing problem, in that they are unable to produce enough surfactant for the growing market demand, so much so that they have begun collecting foam at another smaller abattoir in Prince Edward Island.
“BLES is one of the most widely used products in Canada,” said Fraser.
Although premature birth is one of the main causes of insufficient lung surfactant in newborns, there are other causes. Surfactant-producing cells in the lungs can also be damaged at or shortly after birth in term infants. Things like aspiration pneumonia caused by the ingestion of meconium in the amniotic fluid by the fetus at time of birth, as well as some infants of diabetic mothers for which the diabetes has interfered with the baby’s natural occurring production of lung surfactant, are culprits as well.
“Meconium denatures the surfactant that babies produce, and too much insulin in babies of diabetic mothers inhibits the production of surfactant,” said Lisa MacMain, a NICU nurse working in the B.C. Women’s and Children’s Hospital in Vancouver.
“I have personally cared for babies in both of these scenarios that have received BLES in the course of their treatments. In these situations, you would say they were given BLES for ‘off label’ use.”
Fraser added: “Critically ill adults can also suffer from damage to their surfactant-producing cells. Surfactant therapy has been studied in adults but, so far, has not been as successful as it is in newborns.”
Just last summer, Lawson Health Research Institute in London released a statement saying it had launched a study to investigate the use of BLES in the treatment of COVID-19 patients that were severely respiratory compromised.
It stated that “lung analyses from patients with severe COVID-19-induced respiratory failure indicate there is a change in their alveolar type-II cells; the cells which secrete surfactant. This suggests a change to the surfactant being produced, and a decrease in its functional efficacy.”
The study suggested that if BLES were given at time of intubation, it could reduce the risk of mechanical ventilation, and improve the systemic inflammatory response, gas exchange and length of hospital stay.
“BLES has been studied in pediatric and adult populations with (acute respiratory distress syndrome) ARDS, and we have found that it improves outcomes in patients with direct lung injury when compared to patients receiving standard treatment,” Dr. Jim Lewis, Lawson scientist and respirologist at St. Joseph’s Health Care London, was quoted as saying in the press release. “We have proven this treatment effective in the past, and COVID-19 seems to be another prototypic case that we think will respond well.”
Lawson Health Research Institute was contacted prior to publishing for an update on this status, but it did not respond.