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<p>
This directory contains 121 records (one for each recording in the <a
href="../">MIMIC Database</a>) that contain periodic measurements of
physiologic variables obtained from bedside ICU monitors. This section of the
MIMIC Database is called <em>Numerics</em> because these measurements are those
that typically appear in numeric form on the ICU monitors' screens: heart rate,
blood pressure (mean, systolic, diastolic), respiration rate, oxygen
saturation, etc. Since the data-gathering protocol was designed to have
minimal impact on patient monitoring or care, the selection of measured
variables varies among these records, according to the requirements of the ICU
staff for appropriate care of the patients in each case.
<p>
If you wish to download all of the files in this directory without selecting
each one individually, try using a utility for batch HTTP transfers such as
<a href="/physiotools/utilities/wget/">
<tt>wget</tt></a>, available here in source form for all versions of UNIX and
as a precompiled binary for MS-Windows. Most Linux distributions include
<tt>wget</tt>. Once you have installed <tt>wget</tt>, retrieve these files
using
<pre>
wget -r -np http://www.physionet.org/physiobank/database/mimicdb/numerics/
</pre>
(or substitute the name of a nearby <a href="/mirrors/">PhysioNet
mirror</a> for <tt>www.physionet.org</tt> above). The files in this directory
occupy 548 megabytes.
<p>
These records vary in length from about an hour to more than 77 hours; most are
about 35-40 hours in length. About one-third of the patients in the MIMIC
Database are represented by two (in a few cases, three) recordings. The total
length of these records is approximately 4658 hours.
<p>
The measurements in these records, sampled at intervals of 1.024
seconds (0.976563 Hz), have been derived from the raw signals in the
directories reached from like-numbered links on the <a
href="../">MIMIC Database home page</a>. (At this time, 72 of these
directories have been posted here; the remaining 49 are not yet
available. If you have a particular interest in one or more records
that are not yet on-line, please <a
href="mailto:webmaster@physionet.org">send us a note</a> and we will
attempt to accommodate your request.) The complete MIMIC Database
will include these records, the raw signals, and accompanying clinical
data for each case, extracted from medical records.
<p>
Each of the 121 records consists of a (text) header file, a (binary) signal
file, and 2 (binary) annotation files, identified by suffix:
<p>
<center>
<table>
<tr><td width=10%><em>Suffix</em></td>
<td><em>Meaning</em></td></tr>
<tr><td><tt>.hea</tt></td>
<td>header file, describing signal file contents and format</td></tr>
<tr><td><tt>.dat</tt></td>
<td>signal file</td></tr>
<tr><td><tt>.al</tt></td>
<td>annotations corresponding to patient status alarms</td></tr>
<tr><td><tt>.in</tt></td>
<td>annotations corresponding to monitoring condition alarms</td></tr>
</table>
</center>
<p>
In addition, a fifth (text) file, with suffix <tt>.xws</tt>, is provided for
viewing each record using WAVE. If you are running Linux and have installed
WAVE, you may click on the <tt>.xws</tt> file associated with each record to
view that record without downloading it first. WAVE and the related <a
href="/physiotools/wfdb.shtml"> WFDB software package</a> may be downloaded
from this site.
<p>
<em>Patient status alarms</em> refer to events that (as determined by the ICU
monitor) require medical intervention (for example, observation of heart rate
or blood pressure outside of preset limits). <em>Monitoring condition
alarms</em> refer to events that interfere with the function of the monitor
(for example, transducer malfunction or signal saturation). Note that these
alarms are as reported by the ICU monitors, including all false alarms. Once
an alarm condition is detected, the monitors produce alarms at intervals of
1.024 seconds until reset by the ICU staff, or until the variable that
triggered the alarm returns to its nominal range. There are also significant
events in some cases that did not trigger alarms (and are therefore not
annotated in the <tt>.al</tt> or <tt>.in</tt> files).
<p>
Patient status and monitoring condition alarms were not recorded for the first
5 cases (032, 033, 037, 039, and 041), so the <tt>.al</tt> and <tt>.in</tt>
files for these 5 records are empty.