use strict;
use warnings;

while (<DATA>) {
    s/\|(.*?)\|(.*?)\^/"|$1|".case($2)."^"/e
        if !index $_, 'OBX';
    print;
}

sub case {
    my $s = $_[0];
    $s =~ s/[A-Z]/U$&/g;
    $s =~ s/[a-z]/L$&/g;
    return $s;
}

__DATA__
NTE||L|obr note
OBX|NM|aaA..^Haem^RD2|7.5|g/dL|13.0-18.0|OR|
NTE||L|obx note 1/1 for 3058
OBX|NM|dBf..^TWC^RD2|8.9|10*9/L|4.0-11.0||