To The Editor:
We would like to congratulate Willy et al. for their paper on
compartment pressure monitoring technique ("Measurement of Intracompartmental
Pressure with Use of a New Electronic Transducer-Tipped Catheter
System," 81-A: 158-168, Feb. 1999). Many of the difficulties of
earlier methods appear to have been overcome. No case of compartment
syndrome was missed, and all patients receiving a fasciotomy had
operative findings consistent with an acute compartment syndrome.
We would, however, welcome some further clarification of the
results in Table III detailing the pressures in the monitored patients.
As may be expected, the median pressure values were higher in those
with compartment syndrome, but there was an overlap of pressure
ranges between the two groups. In particular, one patient with an intracompartmental
pressure of thirty-two millimeters of mercury required fasciotomy
but another with a pressure of thirty-three millimeters of mercury
did not. Mention is made of the value of objective data as an adjunct
to clinical examination. If the two patients had been unconscious and
unable to cooperate with clinical assessment, pressure measurements
would not have been able to differentiate between them at that point
in time. We would be interested in the authors' comments on the
specificity of compartmental pressure for the diagnosis of acute compartment
syndrome.
C. T. Gibbons, F.R.C.S.
P. F. Partington, F.R.C.S.(Orth)
Corresponding author: C. T. Gibbons, F.R.C.S.
7 Oakland
Gosforths Newcastle upon Tyne NE3 4YQ, England
E-mail address: chrisgibbons70@hotmail.com
C. Willy, H. Gerngross, and J. Sterk reply:
We thank C. T. Gibbons and P. F. Partington for their comment.
We agree that appropriate clinical assessment is an important component
when diagnosing acute compartment syndromes. Measurement of tissue
pressures, however, provides useful additional information, especially when
clinical signs are lacking or are difficult to obtain (such as in
the case of unconscious or uncooperative patients).
Gibbons and Partington touched on a very important point not
discussed in our paper: intracompartmental pressure thresholds for fasciotomy
of the anterior tibial compartment. Generally, there are two approaches
to this problem. Some investigators have tried to identify an absolute
tissue pressure above which a fasciotomy should be performed2-4,8.
This value has been determined as thirty millimeters of mercury
according to the arterial pressure in the capillary loop. Others
have suggested that a critical pressure value must reflect the decrease
in tissue perfusion, which occurs when the intracompartmental pressure
approaches the perfusion pressure5-7,9. The critical difference
between diastolic blood pressure and intracompartmental pressure
has been estimated as thirty millimeters of mercury. For several
reasons, which are beyond the scope of this reply, we recommend
decompressive fasciotomy when the intracompartmental pressure reaches
thirty millimeters of mercury - at least in severely injured patients.
There are, however, situations in which we do not perform fasciotomy
even in patients with higher intracompartmental pressures. If a
patient suffering from tibial fracture is conscious, if his or her
anterior tibial muscle is not severely injured, if he or she shows
no clinical signs of an acute compartment syndrome, and, finally,
if his or her cardiocirculatory status is stable, emergency fasciotomy
is not imperative. Likewise, a single pressure value as an indicator for
fasciotomy would be very risky in this case. Multiple measurements
should be performed at the level of the fracture, and if the pressure
rises above thirty millimeters of mercury long-term measurements
are necessary.
Indeed, one patient described in our article was suffering from
a tibial fracture (AO classification, type B2) and showed an intracompartmental
pressure of thirty-three millimeters of mercury. We noted a marked swelling
of the muscle and a tense compartment but no intense pain, even
when stretching the anterior tibial muscle. These clinical findings
were the basis for our decision not to perform fasciotomy in spite
of a pressure level of thirty-three millimeters of mercury. Four
hours later, a second check revealed a marked decrease of pressure
to twenty-one millimeters of mercury.
In the other case, the injured patient was unconscious and had
a severe hemorrhagic shock. His open tibial fracture was complicated
by an extensive tissue injury (type IIIB according to the system
of Gustilo et al.1). Here we had to assume that the oxygenation
of the lower leg was impaired and that the microarchitecture of
the nutritive perfusion had been damaged. We decided in this case
to perform fasciotomy.
Christian Willy, M.D.
Heinz Gerngross, M.D.
J�Sterk, M.D.
Corresponding author: Christian Willy, M.D.
Department of Surgery
Military Hospital Ulm
Oberer Eselsberg 40
D-89081 Ulm, Germany