The latest ehealth CPU patch fails to install due to conflicts with patch 25590993 (The OJVM patch).
The following messages occurs during the installation 

D:\update_dir_CPU_2018_Q1\27162953>%NH_ORACLE_HOME_OS%\OPatch\opatch apply -silent -ocmrf %UPDATE_DIR%\OPatch\ocm.rsp 
Oracle Interim Patch Installer version 12.2.0.1.5 
Copyright (c) 2018, Oracle Corporation. All rights reserved. 

Oracle Home : D:\oracle\Oracle.12.1 
Central Inventory : C:\Program Files\Oracle\Inventory 
from : 
OPatch version : 12.2.0.1.5 
OUI version : 12.1.0.2.0 
Log file location : D:\oracle\Oracle.12.1\cfgtoollogs\opatch\opatch2018-04-25_12-52-18PM_1.log 

Verifying environment and performing prerequisite checks... 

Conflicts/Supersets for each patch are: 

Patch : 27162953 
Conflict with 25590993 
Conflict details: 
D:\oracle\Oracle.12.1\javavm\jdk\jdk7\admin\oracle.exe 
D:\oracle\Oracle.12.1\bin\oracle.exe 
D:\oracle\Oracle.12.1\javavm\jdk\jdk6\admin\oracle.exe 
D:\oracle\Oracle.12.1\javavm\jdk\jdk7\admin\oracle.sym 
D:\oracle\Oracle.12.1\rdbms\admin\oracle.sym 

Release:
Component: EHINST

- Create a UPDATE_DIR folder from "C:\" and place the downloaded CPU patch: ORA_WIN_12102_Q1_2018.zip 
- go into the C:\UPDATE_DIR (cd C:\UPDATE_DIR) 
- Uncompress the CPU patch : ORA_WIN_12102_Q1_2018.zip into C:\UPDATE_DIR 
- Go to the folder C:\UPDATE_DIR\27162953 
- set ORACLE_HOME=%NH_ORACLE_HOME_OS% 
- %NH_ORACLE_HOME_OS%\OPatch\opatch apply -silent -ocmrf C:\UPDATE_DIR\OPatch\ocm.rsp 

=> Normaly you get the conflic message : 
.... 
Conflicts/Supersets for each patch are: 

Patch : 27162953 

Conflict with 25590993 
Conflict details: 
E:\oracle\Oracle.12.1\javavm\jdk\jdk6\admin\oracle.exe 
E:\oracle\Oracle.12.1\javavm\jdk\jdk7\admin\oracle.sym 
E:\oracle\Oracle.12.1\javavm\jdk\jdk7\admin\oracle.exe 
E:\oracle\Oracle.12.1\bin\oracle.exe 
E:\oracle\Oracle.12.1\rdbms\admin\oracle.sym 
.... 

To fix the problem we can suggest the following step 

a) Remove the conflict patch for Oracle JVM ( Patch 25590993 ) 
- C:\UPDATE_DIR\27162953>E:\oracle\Oracle.12.1\OPatch\opatch rollback -id 25590993 

b) Apply Jan 2018 CPU patch (27162953) 
- C:\UPDATE_DIR\27162953>%NH_ORACLE_HOME_OS%\OPatch\opatch apply -silent -ocmrf C:\UPDATE_DIR\OPatch\ocm.rsp 
- C:\UPDATE_DIR\27162953>nhStartDb 
- C:\sqlplus sys/[email protected]%NH_DB_CONNECT_STRING% as sysdba 
- SQL> shutdown abort 
- SQL> startup upgrade 
- SQL> exit; 
- C:\UPDATE_DIR>nhExecDatapatch.sh 

c) Download OJVM patches 27440294 and 27650403 from Oracle into C:\Update and uncompress them. 
https://updates.oracle.com/Orion/Services/download/p27650403_121020_MSWIN-x86-64.zip?aru=22083811&patch_file=p27650403_121020_MSWIN-x86-64.zip 
https://updates.oracle.com/Orion/Services/download/p27440294_121020_MSWIN-x86-64.zip?aru=22083809&patch_file=p27440294_121020_MSWIN-x86-64.zip 


c) Apply 27440294 - OJVM pre-req 
- Download OJVM patches 27440294 from Oracle web Site into C:\UPDATE_DIR and uncompress 
https://updates.oracle.com/Orion/Services/download/p27440294_121020_MSWIN-x86-64.zip?aru=22083809&patch_file=p27440294_121020_MSWIN-x86-64.zip 
- cd C:\UPDATE_DIR\27440294 
- E:\oracle\Oracle.12.1\OPatch\opatch apply 


d) Apply April 2018 OJVM patch 27650403 
- Download OJVM patches 27650403 from Oracle web Site into C:\UPDATE_DIR and uncompress 
https://updates.oracle.com/Orion/Services/download/p27650403_121020_MSWIN-x86-64.zip?aru=22083811&patch_file=p27650403_121020_MSWIN-x86-64.zip 
- cd C:\UPDATE_DIR\27650403 
- E:\oracle\Oracle.12.1\OPatch\opatch apply 

e)open a new command prompt 
nhStartDb 
sqlplus sys/[email protected]%NH_DB_CONNECT_STRING% as sysdba 
shutdown immediate 
startup upgrade 
exit 

Please shutdown Oracle instances running out of this ORACLE_HOME on the local system. 
Note - test done by support and not validated by QA but steps above should work.