Software for Detecting Acute Hypotensive Episodes

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To build and install the software in this directory, download it, install wfdbmap (included in the WFDB software package) first, then return to this directory and type


This directory contains two AHE detectors (findahe and ahelabel). They identify AHEs as defined for the PhysioNet/CinC Challenge 2009. Both detectors use the same algorithm, but findahe reads text-format input and produces text-format output, and ahelabel reads a WFDB-format record and produces a WFDB-format annotation file as output.

Also in this directory are two shell scripts (printahe and ahemap), which provide simple command-line interfaces for findahe and ahelabel respectively with inputs from the MIMIC II Waveform Database.

printahe uses rdsamp (from the WFDB software package) to extract ABP mean measurements from a MIMIC II record and to convert them to the text form needed by findahe, which then processes them to produce its output. To find AHEs in mimic2db/a44005/a44005n, for example, run the command:

printahe a44005
The output is written to the standard output; to capture it in a file, run:
printahe a44005 >a44005-AHEs.txt
(for example).

ahemap uses ahelabel to create an annotation file containing the locations of any AHEs in the input record, then uses map-record (from the wfdbmap package) to create PostScript and PNG maps of the input record. To map AHEs in mimic2db/a44005/a44005, for example, run the command:

ahemap a44005
The output is written to four files; in this case, they are, a44005.png,, and a44005.png.

Icon  Name                    Last modified      Size  Description
[PARENTDIR] Parent Directory - [   ] Makefile 2010-07-30 13:18 570 [TXT] ahelabel.c 2009-04-09 14:54 2.8K [   ] ahemap 2012-04-03 11:37 440 [TXT] findahe.c 2012-04-03 11:52 2.5K [   ] printahe 2012-04-03 11:38 282

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Updated Friday, 28 October 2016 at 16:58 EDT

PhysioNet is supported by the National Institute of General Medical Sciences (NIGMS) and the National Institute of Biomedical Imaging and Bioengineering (NIBIB) under NIH grant number 2R01GM104987-09.