Treating heart failure and sepsis with bloodletting and leeches.
The Barber-Surgeons assumed the title of Mr to dissociate themselves
from the Apothacaries because they had been derogatory about their medical
knowledge and therapeutic skills. The prejudices remain today. One effect
of this turf war has been the disappearance of the Barber-surgeons'
treatment for heart failure. Blood letting and leeches had been used for
centuries to treat heart failure before the advent of modern medical
therapy. These surgical treatments rarely get more than a passing mention
in modern discussions of the management of heart failure such as the ABC
of heart failure(1).
Although there have been dramatic advances in the surgical management
of heart failure caused by mechanical problems, such as valvular disease,
medications remain the principle form of treatment for heart failure in
which there are no clearly defined mechanical causes. William Withering
published his account of the benefits of digitalis in heart failure in
1785. In the 19th and early 20th centuries, heart failure associated with
fluid retention was treated with Southey's tubes, which were inserted into
oedematous peripheries, allowing some drainage of fluid. It was not until
the 20th century that diuretics were developed. Vasodilators were not
widely used until the development of angiotensin converting enzyme
inhibitors in the 1970s.
The practice of bloodletting is attributed to Galen who was born in
AD 129. He believed that fevers, apoplexy and headache were caused by an
excess of blood or plethora. In treating fevers he advised two
bloodlettings a day. The first was stopped before the patient fainted and
the second before the patient lost unconsciousness. Galen was very
specific in his instructions about when to draw blood, how much to draw,
the age of the patient, and external influences such as the season,
weather and geographic location (2). The practice continued almost
unchanged for about two thousand years but the indications changed, blood
donation and haemochromatosis being the commonest indications today.
In England therapeutic bloodletting evolved into a practice carried
out along with tooth extractions and other minor procedures by barbers.
After joining forces with the surgeons in an effort to avoid turf battles
it was carried out by the Barber-Surgeons. But by mutual agreement the
boodletting and tooth extractions were left to the barbers and larger
operations to the surgeons. With the advent of apparently effective
medications bloodletting was abandoned and knowledge of its traditional
indications and practices largely lost.
In a recent study 6 healthy subjects were "progressively bled 25%
(range = 21-31%) of their blood volume over a period of 1 h in two
approximately equal aliquots. Equilibration was allowed for 30 min
following the bleed, after which further measurements were made and the
blood was then retransfused over 30 min. There was no consistent change in
any of the haemodynamic variables other than gastric intramucosal
CO2:arterial CO2 gap (PiCO2-PaCO2) after removal of the first aliquot of
blood, although five of the six subjects also demonstrated a fall in pHi.
After removal of the second aliquot of blood, PiCO2-PaCO2 gap and pHi
continued to indicate a worsening gastric intramucosal acidosis; stroke
volume, as measured by suprasternal Doppler, demonstrated a marked fall,
while all other variables measured had not altered consistently or to such
a degree as to elicit a clinical response or cause suspicion of a
hypovolaemic state"(3). As the subjects were supine in these studies they
did not faint or lose consciousness.
Subjects will, however, sometimes faint after donating a unit of
blood if they are not given a cup of tea and time to recuperate. One would
presume, therefore, that as much as 25% or even more of the blood volume
may have been removed in bloodletting and that a gastric intramucosal
acidosis must have been induced. The development of a gastric
intramucosal acidosis of limited magnitude and duration can be well
tolerated notably in marathon runners (4,5).
Bloodletting was done by the barbers in England at the request of
patients and must, therefore, have had some beneficial effect even if it
was just a placebo effect. It is very possible, however, that there were
very real benefits in selected patients especially those in left
ventricular or congestive cardiac failure. In withdrawing blood the
venular outflow pressure from capillaries and cardiac filling pressures
would have been immediately reduced. The pressure gradient between
capillary and interstitial fluid may have been decreased or even reversed
if it was elevated(6,7). A reversal of the pressure gradient in oedematous
patients would have promoted the mobilisation of oedema fluid and
excretion in urine provided renal function was normal. Bloodletting would
also have improved capillary blood flow, which can be severely disturbed
in septic patients, by decreasing viscosity and improving the rheological
Repeated epsiodes of bloodletting will cause anaemia which is an
independent risk factor for adverse outcome in patients with heart failure
(8). As heart failure may cause anaemia by compromising the synthesis in
the Krebs cycle of substrate needed for haemoglobin synthesis and blood
formation in the bone marrow this risk might be a consequence of the
heart failure rather than the cause. In adequately nourished and
oxygenated bone marrow haemoglobin pools should be replenished by
resynthesis unless the bloodletting was repeated too often.
In the short term bloodletting achieves what the venodilators
glyceryl trinitrate and isosorbide mononitrate achieve, a reduction in
venular outflow pressure in capillary beds. In patients with heart failure
venodilators improve exercise performance and reduce mortality (9). Whilst
ACE inhibitors, angiotensin II receptor agonists and beta blockers may
also decrease mortality in patients in heart failure, partly or wholly
by similar mechanisms, inotropes and beta agonists may increase mortality
from heart failure. These medications have not been established to
improve disability-adjusted or un-adjusted longevity.
Bloodletting might have been much more effective than venodilators
and as effective as diuretics for in increasing th tone of the
precapillary sphincters and establishing a pressure gradient between
interstitium and capillary the excretion of oedema fluid would have been
promoted. If in inducing a gastric intramucosal acidosis bloodletting were
also to induce preconditioning by, for example, activating anf K(atp)
channel, bloodletting might even have had extended benefits not seen with
Leeches have also been used in the practice pof medicine for
thousands of years (10) and were often applied to patients in the days of
the Barber-Surgeons. They removed small amounts of blood and might in
addition have given patients a dose of hirudin, an anticoagulant. They
are still used today, in the field of reconstructive or microsurgery, to
salvage tissue flaps and skin grafts whose viability is threatened by
venous congestion. The anticoagulant properties of hirudin, contained in
leech saliva, may yet lead to wider therapeutic applications in the
prevention and treatment of thromboembolic disease. I have not found any
data on their use in the management of heart failure other than the
passing mention of the practice in the ABC of heart failure (1).
When a final year student I did a locum HP job for the late Dr
Carmichael Young as St Mary's hospital in Paddington. I have never
forgotten the comment made whilst seeing a patient with a very painful
acute pericarditis on one of his ward rounds. "The most effective
treatment for pericarditis I have ever seen", he told us,"was three
leeches applied to the paecordium".
Galen avdised bloodletting principally for fevers. As flow through
the microciculaation is seriously disturbed in sepsis by sludging and
rheology is improved by decreasing viscosity, it may indeed have been
effective treatment even in these circumstances.
1. ABC of heart failure: History and epidemiology
R C Davis, F D R Hobbs, and G Y H Lip
BMJ 2000; 320: 39-42.
2. Roy Porter. The greatest benefit to makind. Harper-Collins,
3. Hamilton-Davies C, Mythen MG, Salmon JB, Jacobson D, Shukla A, Webb AR.
Comparison of commonly used clinical indicators of hypovolaemia with
Intensive Care Med. 1997 Mar;23(3):276-81.
4. Otte JA, Oostveen E, Geelkerken RH, Groeneveld AB, Kolkman JJ. Exercise
induces gastric ischemia in healthy volunteers: a tonometry study.
J Appl Physiol. 2001 Aug;91(2):866-71.
5. Rokyta R Jr, Matejovic M, Novak I, Zeman V, Krouzecky A, Novak J,
Trefil L, Linhartova K, Sramek V. Submaximal exercise in healthy
volunteers: the relationship between gastric mucosal and systemic energy
Pflugers Arch. 2002 Mar;443(5-6):852-7. Epub 2001 Dec 11.
6. Boulpaep EL. The microcirculation In: Boron WF, Boulpaep EL.
Medical Physiology. Saunders, Elsevier Science (USA), Philadelphia, 2003.
Chapter 19, pp 463-482
7. Boulpaep EL. Integrated control of the cardiovascular system. In: Boron
WF, Boulpaep EL. Medical Physiology. Saunders, Elsevier Science (USA),
Philadelphia, 2003. Chapter 24 pp 574-590, figure 24-9.
8. D, Nye R, Levy WC. Anemia predicts mortality in severe heart failure:
the prospective randomized amlodipine survival evaluation (PRAISE).
J Am Coll Cardiol. 2003 Jun 4;41(11):1933-9.
9. Kumar P, Clark M. Clinical Medicine. Fifth edition. WQB Saunders,
10. Abdelgabar AM, Bhowmick BK. The return of the leech.
Int J Clin Pract. 2003 Mar;57(2):103-5. Review
Competing interests: No competing interests