Understanding Coding of Hypertension in Pregnancy

Understanding Coding of Hypertension in Pregnancy

Saturday, June 23, 2018

Hypertension in pregnancy still remains as one of the most misunderstood complications of pregnancy, in addition to the incorrect usage of the ICD-10 diagnosis codes that go with it.   ICD-10cm has a specific block of codes allocated to Pregnancy and hypertension, that should be used with all pregnancy coding.  These codes denote a pre-existing hypertention and then the gestational or pregnancy-induced hypertension.

ICD-10cm Code block Group

·         O10  Pre-existing hypertension complicating pregnancy, childbirth and the puerperium

·         O11  Pre-existing hypertension with pre-eclampsia

·         O12  Gestational [pregnancy-induced] edema and proteinuria without hypertension

·         O13  Gestational [pregnancy-induced] hypertension without significant proteinuria

·         O14  Pre-eclampsia

·         O15  Eclampsia

·         O16  Unspecified maternal hypertension

As you can see from the list above, there are numerous codes to choose from.  As coders, we rely on our physicians to give us good clinical documentation within the pregnancy record, so we can code and bill appropriately for their services.  As in the case of a pregnancy that the OB is supervising, the added diagnosis of Hypertension in pregnancy brings added risk factors to that pregnancy oversight.  We also need to add ICD-10cm code for a high risk pregnancy due to hypertension.  The pregnancy supervision code for high risk pregnancy will be coded as the primary code based upon the ICD-10cm guidelines.   ICD-10cm coding guidelines for high-risk pregnancy changed in 2017. The current rule from the 2018 ICD-10-CM Official Guidelines for Coding and Reporting (effective Oct 1, 2017 – Sept 30, 2018) is below:

Supervision of High-Risk Pregnancy (ICD-10-CM Official Guidelines for Coding and Reporting FY 2018 Page 58 of 117) Codes from category O09, Supervision of high-risk pregnancy, are intended for use only during the prenatal period. For complications during the labor or delivery episode as a result of a high-risk pregnancy, assign the applicable complication codes from Chapter 15. If there are no complications during the labor or delivery episode, assign code O80, Encounter for full-term uncomplicated delivery.  

For routine prenatal outpatient visits for patients with high-risk pregnancies, a code from category O09, Supervision of high-risk pregnancy, should be used as the first-listed diagnosis..  

The high risk supervision codes noted below, do not have a category specifically for oversight of hypertension in pregnancy, however this is something that we need to have coded for our diagnoses.  If we are going to add a high risk pregnancy diagnosis to our record, the code choice of O09.89 would the best choice, as the hypertension in pregnancy is in the “other high risk” category and our provided has specified it as such. 

 O09 Supervision of high risk pregnancy

·          O09.0 Supervision of pregnancy with history of infertility

·          O09.1 Supervision of pregnancy with history of ectopic pregnancy

·          O09.A Supervision of pregnancy with history of molar pregnancy

·          O09.2 Supervision of pregnancy with other poor reproductive or obstetric history

o    O09.21 Supervision of pregnancy with history of pre-term labor

o    O09.29 Supervision of pregnancy with other poor reproductive or obstetric history 

·          O09.3 Supervision of pregnancy with insufficient antenatal care

·          O09.4 Supervision of pregnancy with grand multiparity 

·          O09.5 Supervision of elderly primigravida and multigravida

o    O09.51 Supervision of elderly primigravida 

o    O09.52 Supervision of elderly multigravida 

·          O09.6 Supervision of young primigravida and multigravida

o    O09.61 Supervision of young primigravida

o    O09.62 Supervision of young multigravida

·          O09.7 Supervision of high risk pregnancy due to social problems

·          O09.8 Supervision of other high risk pregnancies

o    O09.81 Supervision of pregnancy resulting from assisted reproductive technology

o    O09.82 Supervision of pregnancy with history of in utero procedure during previous pregnancy

o    O09.89 Supervision of other high risk pregnancies

·          O09.9 Supervision of high risk pregnancy, unspecified

In some cases, the high blood pressure diagnosis is present prior to the pregnancy,  however, the patient can develop high blood pressure during pregnancy, which would then be noted as gestational hypertension.   

Ø  Chronic hypertension is high blood pressure that was present before pregnancy or that occurs before 20 weeks of pregnancy. But because high blood pressure usually doesn't have symptoms, the provider may be reluctant to state this as a chronic condition, as this may or may not have been noted as a diagnosis for the patient by a previous provider or prior to the pregnancy.

Ø  Chronic hypertension with superimposed preeclampsia is condition that can also occur in women with chronic hypertension before pregnancy who develop worsening high blood pressure and protein in the urine or other blood pressure related complications during pregnancy.

Ø  Gestational hypertension is the patient noted in the record to have high blood pressure that develops after 20 weeks of pregnancy. Normally there is no excess protein noted in the urine or other signs of organ damage however, some women with gestational hypertension may develop preeclampsia.

Ø  Preeclampsia occurs when hypertension develops after 20 weeks of pregnancy, and is associated with signs of damage to other organ systems, including the kidneys, liver, blood and/or brain. Untreated preeclampsia can lead to serious complications for mother and baby, including development of seizures which then the diagnosis becomes eclampsia.

o   Previously, preeclampsia was clinically diagnosed only if a pregnant woman had high blood pressure and protein in her urine. However, it has been noted that it's possible for the patient to have preeclampsia without having protein in the urine.

Ø  Eclampsia is the onset of seizures (convulsions) in a woman with pre-eclampsia.  The onset may be before, during, or after delivery, but it can be diagnosed and treated  during the second trimester in the  pregnancy.

o   The seizures are usually the  tonic–clonic type and typically last between 30 and 60 seconds.  Complications of eclampsia include aspiration pneumonia, cerebral hemorrhage, kidney failure, and cardiac arrest

Ø  HELLP Syndrome is another variant of pre-eclampsia and/or eclampsia  as a known pregnancy complication. HELLP syndrome is characterized as hemolysis, elevated liver enzymes, and  low platelet count.  HELLP syndrome can be fatal to both the mother and the fetus. 

The clinical documentation of consistent pregnancy blood pressure is an important part of the patients’ prenatal care. The list below designates the levels at which the blood pressures should be noted.  As a coder, if you are not seeing these designations, you will want to query the provider and ensure if the patient has a true “hypertension” or simply an elevated blood pressure.  This will make a difference in your code choice.  This will also determine if the ob visit should be considered part of the prenatal care/OB package, or if it should be billed as a separately identifiable visit outside of the prenatal care/OB package.

o   Elevated blood pressure:  Elevated blood pressure is a systolic pressure ranging from 120 to 129 millimeters of mercury (mm Hg) and a diastolic pressure below 80 mm Hg. Elevated blood pressure tends to get worse over time unless steps are taken to control blood pressure.

o   Stage 1 hypertension: Stage 1 hypertension is a systolic pressure ranging from 130 to 139 mm Hg or a diastolic pressure ranging from 80 to 89 mm Hg.

o   Stage 2 hypertension: More severe hypertension, stage 2 hypertension is a systolic pressure of 140 mm Hg or higher or a diastolic pressure of 90 mm Hg or higher.

NOTE:  After 20 weeks of pregnancy, blood pressures that exceeds 140/90 mm HG — documented on two or more occasions within the prenatal record, that are at least four hours apart, without any other organ damage — is considered to be gestational hypertension. 

As we look to the ICD-10cm coding guidelines, the pre-existing condition (such as hypertension) should be considered carefully. 

Pre-existing conditions versus conditions due to the pregnancy (ICD-10-CM Official Guidelines for Coding and Reporting FY 2018 Page 59 of 117)

Certain categories in Chapter 15 distinguish between conditions of the mother that existed prior to pregnancy (pre-existing) and those that are a direct result of pregnancy. When assigning codes from Chapter 15, it is important to assess if a condition was pre-existing prior to pregnancy or developed during or due to the pregnancy in order to assign the correct code.

Categories that do not distinguish between pre-existing and pregnancy-related conditions may be used for either. It is acceptable to use codes specifically for the puerperium with codes complicating pregnancy and childbirth if a condition arises postpartum during the delivery encounter. 

The ICD-10cm guidelines also go on to say that the “O” codes that have been set forth for hypertension in pregnancy also include the codes for hypertensive chronic kidney disease.  If this is the case we are then to assign not only the appropriate O10 code, but also add an additional code from the appropriate hypertension category from ICD_10cm Chapter 9: Diseases of the Circulatory System (I00-I99) and specify the type of heart failure or CKD.

Pre-existing hypertension in pregnancy (ICD-10-CM Official Guidelines for Coding and Reporting FY 2018 Page 60 of 117)

Category O10, Pre-existing hypertension complicating pregnancy, childbirth and the puerperium, includes codes for hypertensive heart and hypertensive chronic kidney disease. When assigning one of the O10 codes that includes hypertensive heart disease or hypertensive chronic kidney disease, it is necessary to add a secondary code from the appropriate hypertension category to specify the type of heart failure or chronic kidney disease. See Section I.C.9. Hypertension

Office Coding Scenario – Admission to L&D:

Patient is a 32 year old who has come in at the request of our Triage RN status post patient call 1 hr ago. Pt is G2 and P1 at 35 and 3/7 weeks with gestational hypertension stable on labeletol. Pt arrived 20 minutes ago and is now complaining of a severe headache, leg swelling, blurred vision, abdominal pains, and a BP of 170/102.   She notes baby is moving well, but is having contractions.  Her husband is present with her and is very supportive, but concerned.  Sarah has a history of mild pre-eclampsia with her first child who delivered vaginally 2 years ago. She is allergic to PCN with a bad rash noted 4 years ago. Her Blood pressure in the clinic 2 days ago was 140/85.. She was not started on any new medications, nor any changes to her current Labeletal dose,  but was put on bedrest.   She continues to complain of a severe headache.  She is oriented x3, but somewhat sleepy. She has pitting edema bilaterally at a 3+  She has also complained of some mild nausea with no vomiting at this point. No complaints of shortness of breath. Lungs are still clear. She continues to complain of upper abdominal pain. Her urine dip indicated some mild 2+ proteinuria.  Her most recent vital signs are BP158/98, P98 R14, T98.6 .   She has current symptoms of severe pre-eclampsia, with pre-term labor and trending toward eclampsia.  At this time, I will send orders for direct admission to L&D Observation for continued surveillance of severe pre-eclampsia.  Patient directed to L&D.  I will follow with patient at evening rounds.

Coding Considerations:

ICD-10 cm Diagnosis:

O09.89 Supervision of other high risk pregnancies

O14.13 Severe pre-eclampsia third trimester
O60.03 Preterm labor without delivery
Z3A.37 37 weeks gestation of pregnancy

According to the CPT Maternity Care and Delivery guidelines that are noted at the beginning of the maternity care section within the CPT book it clearly states

“Medical complications of pregnancy; (eg cardiac problems, neurological problems, diabetes, hypertension, toxemia, hyperemesis, preterm labor, premature rupture of membranes,trauma) and medical problems complicating labor and delivery management may require additional resources and may be reported separately.” 

Billing/Reimbursement Issues

Some 3^rd party payers may consider the above scenario of care as part of the OB package of care, and not reimburse for the admission to observation as a separately identifiable service outside of the OB package.  If that is the case, CPT does allow for this and you should code, bill and subsequently appeal for your appropriate payment of such. 

Lori-Lynne A. Webb, CPC, CCS-P, CCP, CHDA, CDIP, COBGC and ICD10 cm/pcs Ambassador/trainer is an E&M, and Procedure based Coding, Compliance, Data Charge entry and HIPAA Privacy specialist, with over 20 years of experience.  Lori-Lynne’s coding specialty is OB/GYN office & Hospitalist Services, Maternal Fetal Medicine, OB/GYN Oncology, Urology, and general surgical coding.  She can be reached via e-mail at webbservices.lori@gmail.com or you can also find current coding information on her blog site: http://lori-lynnescodingcoachblog.blogspot.com/.