Cardiac Output Estimation from Arterial Blood Pressure Waveforms 1.0.0

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<div class="notice">
At the time of the <a href="../doc/s54-5.pdf">2005 study by Sun et al.</a>,
the <a href="/physiobank/database/mimic2wdb/">MIMIC II Waveform Database</a>
included 120 pairs of records (the "study records") that included both ABP
waveforms and TCO measurements, and all of these were used in the study.  The
ABP signals, sampled at 125 Hz, can be found in the waveform records, and the
reference TCO measurements, occurring at irregular intervals, can be found in
the companion "numerics" records (identified by the same record names, but with
an appended "n").  Demographic and clinical information, including age, gender,
ICD9 codes, and medications, was available in the
<a href="/mimic2/mimic2_clinical_overview.shtml">MIMIC II Clinical Database</a>
for 117 of the study records.

The file <a href="RECORDS">RECORDS</a> lists the study records, identifying
them by their names within the now-obsolete version 2 of the MIMIC II Waveform
Database, as was used in the study.  If you wish to do anything other than
exact replication of the 2005 study, we recommend using the corrected and
expanded <a href="/physiobank/database/mimic2wdb/matched/">MIMIC II Waveform
Database Matched Subset</a> (for which age, gender, and detailed clinical
information are available) or the much larger MIMIC II Waveform Database,
version 3 (which includes many additional records for which age, gender, and
clinical information are not available).

File <a href="RECORDS-2005">RECORDS-2005</a> also contains the names of the
corrected copies of the study records within the current MIMIC II Waveform
Database, version 3, as well as their version 2 record names, and the subject
IDs for the associated patients' records in the MIMIC II Clinical Database.

File <a href="RECORDS-2014">RECORDS-2014</a> contains an updated list of 535
records from 350 subjects with ABP signals, TCO measurements, age, and gender
in the MIMIC II Waveform Database Matched Subset, and clinical data in the
MIMIC II Clinical Database, including the 117 study records for which
demographic and clinical data are available.

The first column of RECORDS-2005 contains MIMIC II subject IDs for each record,
which can be used to associate waveform and numerics data with demographic and
clinical data.  For example, in the MIMIC II Waveform Database Matched Subset,
the ABP signals and TCO measurements for subject ID "s00020" can be found within
<a href="/physiobank/database/mimic2wdb/matched/s00020/"
></a>.  The
ABP and other signals are in waveform record s00020-2567-03-30-17-47 (as can be
determined at the link above), and the TCO measurements are the non-zero values
of the CO variable in numerics record s00020-2567-03-30-17-47n.  The fields
appended to the subject ID in these record name are the surrogate date (2567
March 30) and the actual starting time of the record (17:47 in the local time
zone where the recording was made).

In the MIMIC II Clinical Database, the initial "s" and any leading zeros are
omitted from the subject ID.  For example, demographic and clinical data for
"s00020" appears in the MIMIC II Clinical Database as subject ID "20".  The
last three cases in RECORDS-2005 are shown as subject ID "sxxxxx"; in these
cases, there are no corresponding records in the MIMIC II Clinical Database,
and age, gender, ICD9 codes, and medications are unknown for these three

The second column of RECORDS-2005 contains the record names from the (obsolete)
MIMIC II Waveform Database, version 2.

For studies that require using the uncorrected data used in the 2005 study,
within <a href="/physiobank/database/mimic2db/"
><tt></tt></a> are
subdirectories for each record, containing WFDB-compatible waveform and
numerics records.  For example, the first entry in RECORDS is a40006; find the
ABP signal in record mimic2db/a40006/a40006
<a href=/physiobank/database/mimic2db/a40006/a40006_layout.hea>[layout
header]</a>, and the TCO measurements in record mimic2db/a40006/a40006n
<a href=/physiobank/database/mimic2db/a40006/a40006n.hea>[header]</a>.

The third column of RECORDS-2005, and any additional columns, contain the
record names from the MIMIC II Waveform Database, version 3.  The contents of
these records are identical to those in the MIMIC II Waveform Database Matched
Subset, except that their .hea files are undated (they contain the starting
times but neither the actual nor the surrogate dates, and they do not contain
the subjects' age and gender).  Note that if there is a gap of an hour or more
in a subject's waveform and numerics recordings, there will be more than one
MIMIC II Waveform Database version 3 record for that subject; although TCO
measurements will be available in at least one of the records for each subject,
they may not be present in all of a given subject's records.  See the
<a href="/physiobank/database/mimic2wdb/">main page</a> for the MIMIC II
Waveform Database, version 3, for details on locating these records.

The other files here contain additional clinical information extracted from the
MIMIC II Clinical Database for 117 of the study records:

<table cellpadding=10>
<tr><td><a href=demographics.txt>demographics.txt</a></td>
<td><p>sex, age*, and mean and standard deviation of hematocrit<br>
* age over 89 is given as >=90</td></tr>
<tr><td><a href=icd9.txt>icd9.txt</td>
<td>ICD9 codes and brief descriptions during the ICU stay</td></tr>
<tr><td><a href=medications.txt>medications.txt</a>
<td><p>intravenous medications administered during the ICU stay<br>
(not necessarily while ABP was being monitored)</td></tr>

The software in <a href=../code/1extract/>../code/1extract/</a> can use the
waveform and numerics records to generate input files for the remaining
software in <a href=../code/>../code/</a>.