Authors: Richard Hollingham
Back in Minneapolis, Walter Lillehei was also working on a heartlung
machine, only his was a good deal simpler. Lillehei decided to
try just the sort of system that everyone else had warned against – one
that bubbled oxygen into the blood. He assigned the task of designing
the new machine to Dick DeWall, a young doctor who had come
to Lillehei with a design for an artificial heart valve – something
DeWall had been working on in the evenings at home (as you do).
Lillehei decided not to mention to DeWall that everyone else
believed that a 'bubble oxygenator' was impossible, if not downright
dangerous. But then they had said the same about cross-circulation.
Bubbling oxygen into the blood is relatively easy. The problem
comes with getting the bubbles out again. DeWall set to work with a
couple of pumps (the same sort of dairy pumps that were being
used for cross-circulation) and some plastic tubing, all held together
with a few bits of tape and some metal hose-clips. The resulting
machine looked too simple to be effective, but that simplicity was
the beauty of the system. The blood from the patient's veins was
pumped into a mixing chamber, where oxygen was bubbled through
a large rubber stopper with hypodermic needles sticking out of it.
The newly oxygenated bright red blood then passed through what
DeWall termed a 'de-bubbler tube' – a diagonal piece of pipe filled
with an anti-foam chemical to break up the surface of any bubbles.
It was the same chemical used in factories to make mayonnaise.
Finally, the blood flowed down a helical spiral. This was probably the
cleverest bit and was designed to defeat any lingering bubbles. The
heavier blood that was free of bubbles rolled downwards with gravity,
while the lighter blood, containing bubbles of air, was forced
back to the top. Finally, the blood flowed out of the helix through
another dairy pump and back into the patient's arteries. The whole
arrangement of pumps, bottles and tubes sat on a trolley beside the
operating table. When the operation was finished the plastic tubes
could be thrown away – no need for the complicated cleaning or
difficult preparation of the Gibbon machine.
The Lillehei-DeWall bubble oxygenator was first put to the test
on 13 May 1955. Unfortunately, the patient later died, but this did
not appear to be down to any fault in the machine. There were so
many other things that could go wrong with this pioneering surgery.
By December one hundred operations had been performed using
the machine. Most of the patients survived. The odds of open-heart
surgery were improving. The machine was refined, improved and
commercialized. Soon any hospital in the world could purchase one.
With the heart-lung machine, surgeons were able to operate on
an open heart free of blood. They could take their time and see
exactly what they were doing. However, one last problem remained:
even with the heart-lung machine connected, the patient's heart
kept beating. Placing precise stitches into a beating heart was difficult,
and the slightest slip could end in disaster. What surgeons
needed was some way to stop the heart beating altogether. Of course,
the other thing surgeons had to be able to do was start it up again.
The answer came from a British surgeon, Denis Melrose,
*
who published his research in the
Lancet
in 1955. He devised an
injection of potassium citrate. He later changed this to potassium
chloride, a compound that disrupts the electrical signals in the
heart. It's the same chemical that forms the basis of the 'lethal
injection' used to administer the death penalty in some US states.
When it was first tried out in Britain on a patient at Hammersmith
Hospital in London, they had to consult a coroner and church
leaders because technically, for the duration of the operation, the
patient was dead. As for starting the heart again, this was done
with electricity applied directly to the heart muscle.
*
Melrose was a remarkable surgeon. As well as his work on stopping the heart,
he also developed a heart-lung machine, which was adopted by hospitals all over the world.
Within the space of a few years, cardiac surgery had been transformed.
From Harken's first quick incision into a beating human
heart to remove a bullet, surgeons such as Melrose and Lillehei were
stopping hearts altogether to open them up and correct major
defects. With the ability to stop the heart came even more daring and
intricate procedures. Patches were stitched across large holes; artificial
heart valves were grafted on; arteries were replaced with synthetic
tubing. Every year more and more patients were undergoing openheart
surgery, and every year more and more were surviving.
In 1958 the personable young Melrose made history by conducting
open-heart surgery live on Californian television. The broadcast
started at 7 p.m. when Melrose began operating on 'Tommy', the
seven-year-old son of an American war veteran. For over four hours
viewers were glued to their small black and white TVs as Melrose cut
open the boy's heart. It was the highest-rated programme that night
– real life drama with the genuine risk that the boy might die on live
television. Tommy survived, but
his
heart was repairable. What about
those hearts that were so badly damaged that no amount of surgery
could fix them? Could the heart – the centre of the soul, the very
core of the body – be replaced with another one?
National Heart Hospital, London, 1969
It was a desperate, last-ditch attempt to save a life. An experimental
procedure to keep a dying patient alive.
One of the UK's leading cardiac surgeons, Donald Longmore,
had put in the call. The farmer assured him that the pigs were on
their way. He would deliver them himself in his Land Rover. It
wouldn't take long. Everything else was ready.
In the operating theatre the male patient lay on the operating
table, his chest open and tubes snaking across to the bulky heartlung
machine. Dark red blood flowed one way, bright crimson
blood flowed back. The machine's regular beating rhythm was keeping
the man alive. The anaesthetist, sitting beside a complex rack
of gas canisters, calmly monitored the patient. A nurse placed some
freshly sterilized instruments on the trolley; another kept an eye
on the machine. All the lights and dials seemed to be indicating
everything was OK. There was little else for the surgeons to do than
wait. For the pigs.
They had decided to call this the 'piggyback' operation. The
surgeons' plan was to graft a pig's heart and lungs into a patient so
that the animal's organs would help keep the man alive. The operation
had been conceived to help someone with serious heart
disease. The pig's heart and lungs would work – or piggyback –
alongside the patient's own heart and lungs to relieve some of the
strain. At the very least it might keep this seriously ill man going for
a few more months before the heart transplants pioneered in 1967
and 1968 were perfected and a suitable donor found. It might last
even longer. It could even be another 'miracle breakthrough' the
newspapers were so fond of reporting. As usual, the procedure had
been tried on other animals and it seemed to work. The patient was
seriously ill, his heart ailing. This experimental operation offered
the only chance of survival.
Everyone waited for the pigs.
The farmer pulled up to the mews at the back of the hospital.
The first inkling Longmore had that it was going to be a long night
was when Thompson, the head porter, called him. 'Mr Longmore,
is that pig in a Land Rover in the mews anything to do with you?'
'Yes, it is.'
'Well, it has just got out and turned left along Wimpole Street.'
Reluctant to make its own valuable contribution to medical
progress, the pig had escaped. It is surprising how fast a pig
can run, especially when its life is at stake. Still dressed in their
operating theatre gowns, caps, masks and boots, the entire surgical
team gave chase.
The pig ran as fast as its little legs could carry it, but was no
match for London's finest heart surgeons, who eventually caught it
halfway up the road. The pig squealed in protest, but Longmore
herded it back towards the hospital. It was five o'clock in the
evening and people were heading home from work, so the street was
relatively busy. Most passers-by paid little attention to the odd group
in the road. Only one gentleman seemed a little perturbed. Raising
his bowler hat, he said, 'Excuse me, sir. You are going the wrong way
along a one-way street.'
Back in the operating theatre, the anaesthetized patient lay on
the table. The heart-lung machine pumped and breathed on his
behalf. The nurses and surgeons stood around. The clock ticked.
Where was the pig?
The pig was with Longmore in the lift. He wasn't going to let it
get away this time. There were also a few hospital visitors in the lift,
but no, they didn't mind if the lift went straight to the top floor
marked 'mortuary'. What business was it of theirs if the surgeon
fancied having pork for his supper?
Arriving at the mortuary, Longmore had arranged for an anaesthetist
to put the pig to sleep so that it could be killed and its organs
removed. When the anaesthetist assigned to the task showed up, he
turned out to be Jewish. He refused to kill the pig. Another anaesthetist
was found, but by now Longmore was beginning to wonder if
all this grief was going to be worth it.
In the operating theatre, the heart-lung machine continued to
pump. The surgeons and nurses waited.
The heart and lungs were eventually removed from the pig,
but now there was another problem: the patient was also Jewish.
What were the chances? The patient himself was in no position to
reassess the merits of the operation, so rather than panic (or pray),
Longmore did the next best thing – he rang a rabbi.
When Longmore explained what they were trying to do, the
rabbi went very quiet. The surgeon apologized for putting him in
such a difficult position and understood if he didn't want to get
involved. There was another long, somewhat muffled silence.
Finally, the rabbi could hold back no longer. 'Sorry,' he said. 'I was
trying to stop laughing.' The rabbi told Longmore that if this was
a genuine attempt to save the man's life, then certainly he should
go ahead. First the escaping pig, then the Jewish anaesthetist,
now this. Another obstacle overcome. At last the surgeons could
get on with the operation.
It was a relief to return to the operating theatre. Once he had
changed and scrubbed, Longmore was ready to begin. The heartlung
machine continued to pump. The dark red blood flowed in;
the bright red blood flowed out. The patient was still alive, the pig
heart was ready. The operation could get under way.
The operation itself seems to be going surprisingly well. The
heart is stitched into the patient's circulation ready to help keep
him alive. The final part of the procedure involves a simple injection
of calcium to the pig's heart. In humans calcium is used to increase
muscle strength. However, as Longmore now discovers, it has a
different effect altogether in pigs. The pig's heart sets like a stone.
It is useless, and after all that effort the operation fails and the
patient dies. It is little consolation to the surgeons that he would
have died anyway, but at least they have learnt from the experience.
The story became known as the 'night of the pigs', and to cap it
all, the feared hospital matron had been woken up by pig squeals
and was furious. A member of the surgical team sent her pork chops
for breakfast, which hardly helped.
Groote Schuur Hospital, Cape Town, 3 December 1967
Compared to bullet wounds, hibernating groundhogs, crosscirculation
and porcine predicaments, heart transplantation itself is
a relative anticlimax. In 1967 the race was on to be the first surgeon
to transplant a human heart. There was no knowing who would get
there first, and although many surgeons talked of sharing their
results and cooperating with their rivals, secretly most of them
would admit that they wanted to be the one to get the credit and
possibly a little bit of glory.
Many believed the first would be Norman Shumway, a surgeon
at Stanford in California, who had been working for almost ten years
on perfecting the heart transplant technique in animals. Shumway
had presented his first heart transplant results on dogs in 1961, and
was now ready to try it on humans. He had developed new combinations
of drugs to prevent the heart from being rejected by the body
(see Chapter 3). He even went on to suggest that transplanting a
heart should be a relatively straightforward surgical procedure, and
less likely to end in rejection than, say, a skin or kidney transplant.
Elsewhere in the United States, down in Mississippi, James
Hardy was waiting for a human donor for a terminally ill heart
patient. With no suitable transplant available, he tried transplanting
the heart of a chimpanzee, but this proved unsuccessful.
Meanwhile, many European surgeons were keen to steal a march on
the Americans – there was national, as well as personal, pride at
stake. So far, most of the cardiac 'firsts' had been by Americans. In
France, hospitals were said to be ready, and in London Donald
Longmore at the National Heart Hospital was waiting for the right
combination of patient and donor, having spent the previous
few months battling with a bunch of 'oily' bureaucrats from the
Department of Health.
They were all beaten to it by a relatively unknown, although
hardly unqualified, South African surgeon. Christiaan Barnard had
been trained by Walter Lillehei in Minneapolis and had a good, if
inconspicuous, surgical pedigree. His record for complicated openheart
surgery was remarkable. The chances of surviving a Barnard
operation were extremely good. Like many of the most successful
heart surgeons, he thought of the organ as merely a 'primitive
pump' – one that demanded respect, but commanded no great
mystical power, no soul.