Benchmarking with National ICD-9-CM
by Carol E. Osborn, PhD, RRA
As HIM professionals, we want to be
assured that we are providing the highest quality data for reimbursement
and research purposes. We can review coded data internally, but this does
not give us a clear picture of the total information that is being submitted
to the Health Care Financing Administration (HCFA). Recently a new tool
has come out that helps HIM professionals evaluate the quality of coded
data. This tool, DRG Resource Book: Data for Benchmarking and Analysis,1
is published by the Center for Healthcare Industry Performance Studies
in Columbus, OH. The book contains comparative information for the top
50 medical and the top 25 surgical DRGs for the Medicare population, so
HIM professionals can compare their coded data to a national database.
The source of this information is the HCFA Medicare Provider and Review
File (MedPAR file) for the federal fiscal year 1995, which consists of
data compiled from UB-92 data submitted by hospitals for inpatient Medicare
This resource reports DRG summary
information, cost analysis information, state specific profiles of charges
per discharge and by department, utilization and quality indicators, and
clinical coding analysis-all by DRG. This article will analyze the ICD-9-CM
codes reported for the 75 medical and surgical DRGs. The clinical coding
analysis section presents information on ICD-9-CM principal and related
secondary diagnoses for each DRG, as well as procedural codes. As an example,
refer to the clinical data reported for DRG 462 in Table 1, below.
The DRG tables that appear in this
article display the most common secondary diagnoses that appear, combined
with the top principal diagnoses listed for a specific DRG. For example,
Table 1 lists the principal and secondary diagnoses codes for DRG 462,
Rehabilitation. For the principal diagnosis code of V57.89, approximately
36 percent of the patients have a secondary diagnosis of hypertension
(401.9), and approximately 17 percent have a secondary diagnosis of late
effect of CVA (438). The last column, percent of DRG total, indicates
the total percentage of cases falling into DRG 462 that have a particular
principal diagnosis, and is interpreted as follows: 65.5 percent of the
cases falling into DRG 462 have a principal diagnosis code of V57.89.
In analyzing these data for benchmarking
purposes we can identify areas for quality reviews in our own facilities.
The information in this resource book should be used only as indicators
for possible quality reviews, as it is impossible to determine the actual
combinations of principal and secondary codes for any case or facility.
The information is presented as summary data and should be viewed as indicators
only. The results of analysis will be discussed only in terms of quality
of the coded data. ICD-9-CM coding quality problems most commonly encountered
were related to:
incorrect combination of codes or failure to assign multiple codes when available
nonspecific DRGs/signs and symptoms
use of complication codes
- lack of coding specificity
Each of these will be discussed in
the order identified.
Lack of Coding Specificity
Use of Subclassification 414.00
One of the most common errors revealed
was lack of coding specificity. ICD-9-CM coding principles require that
"codes must be assigned to the highest level of specificity."2
An example of lack of specificity is the use of the following code from
category 414, other forms of chronic ischemic heart disease:
414.00, coronary atherosclerosis,
unspecified type of vessel, native or graft
In this category, the fifth digit
indicates the nature of the coronary artery involved: native vessel or
Although the physician may not directly
state whether the vessel is native or grafted, the information can be
obtained from review of the medical record. Reviewing the history and
physical exam or reading the reports of cardiac catheterization if the
condition was treated during the current hospitalization may provide the
required information. The diagnostic code 414.00 appeared in combination
with procedure codes for cardiac catheterization. This may be an indication
that coders are not reading the entire record when coding, or that coding
takes place before all reports are available. The ICD-9-CM Coding Handbook
states that "If the medical record makes it clear that there has
been no previous bypass surgery, code 414.01, coronary atherosclerosis
of native coronary vessels can be assigned."3,4
Even though a change in the fifth-digit
assignment may not cause a change in the DRG assignment, it is important
to remember that one of the original purposes of coding and classification
systems was to serve as a research database. The ability to distinguish
between arteriosclerosis in native and grafted arteries is important in
both cardiovascular and outcomes research.
Use of Subclassification 342.90
Another commonly used unspecified
code was 342.90, unspecified hemiplegia. Use of 342.90 appears in DRGs
12, 14, and 462. The unspecified refers to side affected by hemiplegia-the
patient's dominant or nondominant side. This may be, in part, due to problems
with documentation. In general, physicians usually indicate side affected
as either right or left rather than dominant or nondominant. If this is
the case in your facility, a medical staff in-service may be appropriate.
In DRG 12, Degenerative nervous system
disorders, code 342.90 appears as the principal diagnosis for approximately
15 percent of the cases, and code 342.91, hemiplegia, dominant side, appears
as the principal diagnosis for approximately 5 percent of the cases. When
evaluating the cases assigned to DRG 12, it is difficult to determine
the reason for an inpatient admission to an acute care facility for hemiplegia.
Both urinary tract infection (599.0) and dehydration (276.5) appear as
secondary diagnoses but not in sufficiently high numbers to account for
most of these admissions. And, since these conditions were not identified
as the principal diagnosis, the medical necessity for these admissions
could be in question. We could also question whether these patients were
actually admitted for rehabilitation instead of the hemiplegia. If this
turns out to be the case, a principal diagnosis code from category V57
should be selected; the cases would then group to DRG 462.
For DRG 14, Specific cerebrovascular
disorder except TIA, code 342.90 appears as a secondary diagnosis in a
range from 15.7 percent to 22.1 percent of the time depending on the principal
In DRG 462, Rehabilitation, code 342.90
appears as a secondary code ranging from 14.3 percent to 18.1 percent
of the time (see Table 1). Since these patients were admitted for rehabilitation,
there should be documentation in the record indicating the side affected.
In order to identify these types of documentation problems, clinical pertinence
reviews should be conducted.
Respiratory Failure and Congestive Heart Failure
Respiratory failure, code 518.81,
is a diagnosis that appears in combination with chronic conditions in
several DRGs. There are several guidelines that address the sequencing
of respiratory failure under certain circumstances, depending on whether
the underlying condition is respiratory or nonrespiratory. When the condition
that occasioned the admission to the hospital is respiratory failure due
to an underlying respiratory condition, the respiratory failure is sequenced
first, with an additional code for the underlying respiratory condition.
However, when the underlying condition is nonrespiratory in nature, the
following guidelines apply:5
These guidelines impact several DRGs,
particularly DRG 87, pulmonary edema and respiratory failure (see Table
2). For 84.5 percent of the cases assigned to this DRG, the principal
diagnosis was 518.81 respiratory failure. Of these, 33.95 percent of the
cases designated congestive heart failure (CHF), code 428.0, as a secondary
diagnosis. Congestive heart failure appeared as a secondary diagnosis
in DRG 87 more often than any other condition. Acute exacerbations of
CHF may be manifested by nocturnal dyspnea, orthopnea and/or pedal edema,
conditions that may lead to respiratory failure. In these situations,
the CHF is an acute exacerbation of chronic nonrespiratory condition,
and it should be sequenced as the principal diagnosis per guideline two.
- If the patient is admitted in respiratory failure due to or associated with an acute nonrespiratory
condition, the acute condition is sequenced as the principal diagnosis
- If the patient is admitted with respiratory failure due to or associated with an acute exacerbation of
a chronic nonrespiratory condition, that condition is sequenced as the
- When the patient is admitted
in respiratory failure due to or associated with a chronic nonrespiratory
condition, the respiratory failure is sequenced first
This change does have an impact on
DRG assignment and reimbursement. When CHF is designated as the principal
diagnosis, the cases group to DRG 127, Heart failure and shock. The 1995
HCFA weight for DRG 87 is 1.3306; the corresponding weight for DRG 127
is 1.0239, a net change of -.0367. This may be another example of inadequate
documentation. The physician may have been unclear in documenting the
conditions as acute exacerbations of CHF. In view of the rules and regulations
regarding compliance, it becomes essential that we educate physicians
on the importance of documentation in the correct assignment of ICD-9-CM
If the respiratory failure were a
manifestation of chronic obstructive pulmonary disease (COPD), it would
be correct to designate it as the principal diagnosis. A similar situation
also exists in surgical DRG 483, Tracheostomy except for face, mouth and
neck diagnoses. But since the DRG's partitioning is based on the performance
of a tracheostomy, the DRG assignment is not affected.
Upon further examination of the coded
data in DRG 87, other quality problems emerge. In DRG 87 there are cases
where COPD, code 496, appears in combination with code 491.21, obstructive
chronic bronchitis with acute exacerbation. This latter condition is considered
an acute exacerbation of COPD, and only one code is required-491.21.6,7
Also in DRG 87, the principal diagnoses of acute pulmonary edema, code
518.4, and pulmonary congestion, code 514, are manifestations of CHF,
and are included in the code for CHF, 428.0.8 These coding combinations
represent cases that should be regrouped to DRG 127.
Similar sequencing errors appear in
DRG 475, Respiratory system diagnosis with ventilator support. Approximately
41 percent of the cases in this DRG had respiratory failure, code 518.81.
Of these, approximately 42 percent had CHF designated as a secondary diagnosis,
and 32 percent had COPD listed as a secondary diagnosis. In these cases
it cannot be determined whether the respiratory failure is a manifestation
of the CHF or COPD. If it is the former, CHF should be sequenced as the
principal diagnosis, which would result in regrouping the cases to DRG
Another example of questionable sequencing
of codes appears in DRG 429, Mental diseases and disorders. In this DRG,
there are a number of cases of the various types of dementia that appear
as the principal diagnosis when these conditions are associated with Alzheimer's
disease (see Table 3). "Alzheimer's is a progressive atrophic process
involving degeneration of nerve cells [which] leads to mental changes
that range from subtle intellectual impairment to dementia with loss of
cognitive functions and failure of memory. Alzheimer's disease is coded
to 331.0; when there is associated dementia, 294.1 is assigned as an additional
code."9 Also, per coding guideline 2.2, "... codes in slanted
brackets in the alphabetic index can never be sequenced as the principal
diagnosis (331.0 [294.1]).10 Examination of the data in Table 3 indicates
that the codes for dementia were incorrectly assigned when associated
with Alzheimer's disease. When Alzheimer's is sequenced as the principal
diagnosis, the cases group to DRG 12, Degenerative nervous system disorders,
which has a weight of .9574 as compared to a weight of .9269 for DRG 429,
a difference of +.0305.
Incorrect Combination of Codes
Intermediate Coronary Syndrome
There are many cases of possible inappropriate
combination of codes throughout the various DRGs. We have already discussed
some examples-496 (COPD) with 491.21 (obstructive chronic bronchitis with
acute exacerbation). Other examples appear in DRG 106, Coronary bypass
with cardiac catheterization, DRG 107, Coronary bypass without cardiac
catheterization, and DRG 124, Circulatory disorders except acute MI with
cardiac catheterization and complex diagnosis. In these DRGs, code 411.1,
intermediate coronary syndrome, appears in combination with codes from
category 410, acute myocardial infarction. According to ICD-9-CM guidelines,
except for conditions described as post-myocardial infarction syndrome
(411.0) and/or post-infarction angina, "no code from category 411
is assigned with a code from category 410."11 Code 411.1 should not
be assigned as a principal diagnosis (DRG 124), when the underlying cause,
such as coronary arteriosclerosis (414.0x), has been identified. However,
code 411.1 would be assigned as an additional diagnosis.12 If these combinations
of codes appear in your own facility's databases, an in-service program
for the coding staff may be appropriate.
Atherosclerosis of the Extremities
A second example of incorrect combination
of codes, or more specifically, the failure to use combination codes when
available, appears in DRG 113, Amputation for circulatory system disorders
except upper limb and toe. For example, the code 440.24, Atherosclerosis
of native arteries of the extremities with presence of gangrene, may appear
in combination with the code for gangrene, 785.4. Since gangrene is included
in 440.24, the assignment of a separate code for gangrene is redundant.
"Ulceration associated with arteriosclerosis of the extremities is
classified to code 440.23 or to 440.24 when gangrene is present."13
Hypertensive Heart Disease, Hypertensive
Renal Disease, and Congestive Heart Failure
The coding of renal failure, hypertension,
and congestive heart failure can be problematic as they require the use
of combination codes. The categories for classifying hypertensive heart
- 401-Essential hypertension
- 402-Hypertensive heart disease
- 403-Hypertensive renal disease
- 404-Hypertensive heart and renal disease
Assigning codes for renal failure
when it appears with hypertension and congestive heart failure can be
very complex, as there are many rules that must be followed. When chronic
renal failure and hypertension appear together in the diagnostic statement,
it should be assumed that there is a relationship between the two conditions
even when it is not specifically stated by the physician.14 A code from
category 403, Hypertensive renal disease, is assigned with a fifth digit
to indicate the presence of chronic renal failure. Thus, only one code
is needed to describe the two conditions-hypertension and chronic renal
failure-403.91. In DRG 120, Other circulatory system OR procedures, the
following redundant combination of secondary diagnosis codes appears:
403.91, Hypertensive renal Dx with chronic renal failure, 585, Renal failure,
and 401.9, Hypertension, unspecified.
The second most frequently occurring
principal diagnosis in DRG 120 is congestive heart failure (428.0), accounting
for 11.5 percent of the DRG total. When the diagnostic statement indicates
that the CHF is due to hypertension, a code from category 402 should be
assigned, with a fifth digit to indicate the presence of CHF. If the CHF
is hypertensive, and chronic renal failure is also present, a code from
category 404, Hypertensive heart and renal disease, should be assigned.
A fifth digit is assigned to indicate the presence of CHF, renal failure,
or both. These data indicate that DRG 120 would be an ideal choice for
quality reviews in healthcare facilities.
As an added note, the combination
code for hypertensive heart disease with CHF, category 402, is rarely
seen in the DRG Resource Book. Codes 428.0 and 401.9 often appear in combination
with each other. Records should be reviewed to determine whether the more
appropriate code assignment is from category 402, Hypertensive heart disease,
with the fifth digit indicating the presence of CHF. DRGs to be reviewed
are: 88, 89, 96, 110, 116, 121, 124, 127, 132, 138, 140, 141, 296, 320,
331, 395, 416, and 477. Since space for reporting diagnoses is limited,
using combination codes where appropriate allows for reporting of more
conditions relevant to the patient stay. For example, there are several
DRGs where hemodialysis is reportedly performed with no corresponding
diagnosis for chronic renal failure, code 585.
Questionable/Incorrect Code Assignments
The code for cardiac arrest (427.5)
should only be assigned under certain circumstances for hospital inpatients.
The code for cardiac arrest is assigned as a secondary diagnosis only
when the patient is resuscitated or resuscitation has been attempted.15
The code for cardiac arrest is never assigned merely to indicate that
a patient has died. The cardiac arrest code is assigned as a secondary
diagnosis for many cases in DRG 123, Circulatory disorders with acute
myocardial infarction, expired. Since only cases of patients who have
expired can be grouped to this DRG, it is unnecessary to code cardiac
arrest to indicate that death occurred. It would be appropriate to review
this DRG because the procedure code for cardiopulmonary resuscitation,
although not mandatory, does not appear more than 5 percent of the time
in combination with the code for cardiac arrest.
Another DRG that should be examined
is 130, Peripheral vascular disorders with CC. Cellulitis, code 682.6,
appears as a secondary diagnosis with a number of cases grouped to this
DRG. Cellulitis may appear as a complication of chronic skin ulcers. When
this situation occurs, a code from categories 707.0-707.9, chronic ulcers
of the skin, is assigned. Since these codes do not include cellulitis,
two codes are required to describe the condition.16 For the cases indicated,
one would expect that the cellulitis, if it exists, would be a complication
of a skin ulcer of the lower extremity. With the exception of principal
diagnosis code 454.2, varicose vein ulcer, inflamed, there is no indication
that an ulcer exists. When the cellulitis is described as gangrenous,
it should be reclassified to category 785.4, gangrene, rather than to
categories 681 and 682.17
Other DRGs in which the code for cellulitis
appears are 263, Skin graft and/or debridement for skin ulcer or cellulitis
with CC, and 277, Cellulitis, age greater than 17 with CC. For DRG 263,
the average length of stay was 14.0 days, and 58.3 percent were transferred
to "other facilities" upon discharge. Given this information,
one might consider whether the cases in which cellulitis is identified
as the principal diagnosis are actually cases of decubitus or other types
of chronic ulcers complicated by cellulitis. For DRG 263, 64.9 percent
of the cases have either decubitus or chronic ulcers indicated as the
principal diagnosis. Cellulitis appears as the principal diagnosis for
approximately 25 percent of the cases in DRG 263. In these cases, cellulitis
described as gangrenous is classified to gangrene, 785.4, rather than
to categories 681 and 682, cellulitis, with an additional code from categories
707.0-707.9 to indicate the type of ulcer.18
The cases in DRG 277 are very similar
to those in DRG 263. The average length of stay for this group of patients
is 6.8 days, with 35.4 percent of the cases transferred to "other
facilities" following discharge. The length of stay is shorter because
DRG 277 is a medical DRG. Since cellulitis usually occurs as a complication
of an ulcer or other type of open wound, one would expect to see codes
for these conditions. For approximately 71 percent of the cases in DRG
277, the site of the cellulitis is either the foot or the leg. Are these
actually manifestations of peripheral vascular disease? For approximately
4 percent of the cases the site of the cellulitis is the trunk. In this
case, is the cellulitis actually a complication of a decubitus ulcer?
If skin ulcer or decubitus ulcer could be documented as the principal
diagnosis, the cases would regroup to a DRG 271, Skin ulcer, a DRG with
a higher weight.
Pathological Fractures vs. Traumatic
Correct coding of fractures also appears
to be problematic. Pathologic fractures are not an uncommon occurrence
in the elderly, especially among women. Pathologic fractures may be the
result of osteoporosis, metastatic tumor of the bone, osteomyelitis, Paget's
disease, disuse atrophy, hyperparathyroidism, and nutritional or congenital
disorders. Fractures described as spontaneous should always be considered
as pathological in nature. When an injury is described as a compression
fracture, the record should be reviewed to determine whether any significant
trauma has occurred. A compression fracture in an older patient that resulted
from a slight stumble or other minor injury should be considered a pathological
fracture, especially when the patient suffers from a disease that frequently
causes this condition.19 But it is important to remember that only the
physician can make the determination that the fracture is out of proportion
to the degree of trauma.20 This may be another area in which clinical
pertinence reviews would assist in identifying quality documentation problems.
In examining the codes for fractures,
it appears that a fracture in the Medicare population was coded as a traumatic
fracture more often than a pathological fracture. The data in Table 4,
below, reveals that most individuals treated for fractures are women
whose average age ranges from 75-81. And 100 percent of the principal
diagnoses codes for DRGs 210, Hip and femur procedures except major joint
procedures, age greater than 17 with CC, and DRG 236, Fractures of the
hip and pelvis, are traumatic. One would have to suspect that perhaps
pathological fractures should be the more common problem, rather than
fractures due to trauma-especially when the average age for these DRGs
is 80, and a high proportion of the patients are female.
Cases that are grouped to DRG 210
would not be affected by a change from traumatic to pathological fracture
code since it is a surgical DRG. However, if any of the principal diagnoses
coded as trauma fractures in DRG 236 are actually pathological fractures,
the cases would be regrouped to DRG 239. The weight for DRG 239 is 1.0388
versus a weight of 0.7772 for DRG 236, a difference of +0.2616.
In DRG 243, principal diagnosis codes
for traumatic fractures of the vertebrae appear in combination with osteoporosis
(733.00). If these were actually pathological fractures, the cases would
regroup to DRG 239. This change would result in a weight change of +0.314.
Nonspecific DRGs/Signs and Symptoms
Chest Pain and Angina Pectoris
In evaluating the coded data throughout
the various DRGs, it appears that there is not a clear understanding of
appropriate use of codes as principal diagnoses for signs and symptoms.
As an example, 30 percent of the cases in DRG 125, Circulatory disorders
except acute myocardial infarction with cardiac catheterization without
complex diagnosis, designate code 786.50, Chest pain, as the principal
diagnosis, while 26 percent of these cases designate code 414.01, Coronary
atherosclerosis, as a secondary diagnosis (see Table 5, below). Coding
guideline 2.1 states that when a related definitive diagnosis has been
established, codes for signs, symptoms, and ill-defined conditions (from
Chapter 16 of ICD-9-CM) are not to be designated as principal diagnoses.21
This is further supported by the fact that cardiac catheterizations were
performed, as indicated by the DRG title, thus atherosclerosis should
have been designated as the principal diagnosis.
In 5 percent of the cases assigned
to DRG 125, code 413.9, Angina pectoris, is assigned as the principal
diagnosis, and 26 percent of these cases assign code 414.01, Coronary
atherosclerosis, as a secondary diagnosis. Angina pectoris is a manifestation
of ischemic heart disease. When the underlying cause is known, i.e., the
atherosclerosis, it should be sequenced as the principal diagnosis. The
performance of cardiac catheterizations lends support to the designation
of atherosclerosis as the principal diagnosis. Chest pain NOS, 786.50,
is the principal diagnosis for 30 percent of the cases in this DRG; angina
pectoris and coronary atherosclerosis appear as secondary diagnoses. These
cases should be evaluated to determine whether atherosclerosis should
be sequenced as the principal diagnosis.
Similar use of code 413.9, Angina
pectoris, as a principal diagnosis appears in DRG 140, Angina pectoris.
Approximately 25 percent of the cases in this DRG have angina pectoris
designated as the principal diagnosis in combination with the codes for
atherosclerosis, 414.00 and 414.01, as secondary diagnoses. According
to coding guideline 2.1, atherosclerosis should be identified as the principal
diagnosis. If the same combination of codes that appear in DRG 140 were
resequenced with 414.00 or 414.01 as the principal diagnosis, the cases
would regroup to DRG 132, Atherosclerosis with CC, resulting in a positive
weight change of +.1038 (from DRG 140, weight 6257 to DRG 132, weight
In DRG 143, Chest pain, a combined
total of 97.9 percent of the cases have one of the following designated
as the principal diagnosis: 786.50, Chest pain NOS; 786.59, Chest pain
NEC; and, 786.51, Precordial pain (see Table 5). Coronary atherosclerosis,
414.00 and 414.01, appear as secondary diagnoses in 68 percent of these
cases. Resequencing these cases with coronary atherosclerosis as the principal
diagnosis would regroup the cases to DRG 133, Atherosclerosis without
CC-a DRG with a higher weight.
Although the principal diagnosis code
V71.7, Observation for suspected cardiovascular conditions, accounts for
less than 1 percent of the cases that are grouped in DRG 143, it is important
to point out that when a related diagnosis is established, or these are
related signs or symptoms, the code for that condition or symptom is assigned
as the principal diagnosis rather than a code from category V71. According
to coding guideline 2.8, codes from category V71 are ordinarily assigned
as solo codes except when a chronic condition requires care and monitoring
during the stay.22
Syncope and Collapse
In DRG 141, Syncope and collapse with
CC, and DRG 142, Syncope and collapse, the code for syncope and collapse,
780.2, appears as the principal diagnosis in 82 percent and 89 percent
of the cases respectively. Syncope is often due to cardiac problems such
as ventricular asystole, bradycardia, or ventricular fibrillation. If
the syncope is related to any of the heart conditions that appear as the
secondary diagnoses (hypertension, atrial fibrillation, congestive heart
failure, and/or cardiac dysrhythmias), the cases should be re-sequenced
with the related cardiac condition sequenced as the principal diagnosis.
Use of Complication Codes-Categories
Use of codes from categories 996-999,
Complications of surgery and medical care, is not always clear. Coders
should be aware that conditions that occur following medical or surgical
care are not always classified as complications. A routinely expected
occurrence that follows medical or surgical treatment is not considered
a complication. For a condition to be classified as a complication:
- there must be a cause and effect
relationship between the treatment and the condition
- there must be an indication that
the condition is a complication, not a postoperative condition in which
no complication is present
- complications due to procedures
must be documented by the physician23
Before assigning codes from categories
996-999, the coders should carefully review all include and exclude notes.
Categories 996-999 have different levels of specificity-some requiring
additional codes to provide more information about the specific complication.
The varying levels of specificity are summarized for each category as
- Category 996 classifies conditions
that result from the presence of an internal device, implant, or graft
and an additional code is usually not required24
- Category 997, complications affecting
specified body systems not elsewhere classified, "are general in
nature and offer little specificity...These codes are not assigned when
the alphabetic Index provides another code...When a code from category
997 is assigned, an additional code for the condition is ordinarily
assigned to provide specificity25
- Category 998, other complications
of surgery, not elsewhere classified, is used to classify a miscellaneous
group of postoperative complications. For the most part, these codes
do not require additional codes because the complication itself provides
- Category 999, complications of
medical care not elsewhere classified, classifies a number of specific
conditions that may follow procedures or conditions that may result
from medical care27
As an example, in DRG 130, 3.2 percent
of the cases have a principal diagnosis of 997.2, surgical complication,
peripheral vascular system. Codes from category 997 "are general
in nature and provide little specificity."28 When a code from category
997 is selected, an additional code for the specific complication is ordinarily
assigned to provide more specificity.29 In this DRG, less than one percent
of the cases for the principal diagnosis code, 997.2, have the peripheral
vascular complication identified. It could be assumed that cellulitis
is the secondary diagnosis that is considered to be the peripheral vascular
complication. This could be questioned however. If this is actually a
postoperative wound infection, the codes should be 998.59, Other post-operative
infection, and 686.2, Cellulitis.
Codes from category 997 appear as
a principal diagnosis in a number of DRGs; in many cases, without an additional
code to identify the specific complication. These codes are listed in
Table 6, below.
One must use caution when assigning
codes to indicate complications of medical and/or surgical care. The coder
should be careful to differentiate complications from routinely anticipated
occurrences. Code 285.1, Acute hemorrhagic anemia is sometimes assigned
following surgery-the coder should recognize that bleeding following surgery
is anticipated. Also, a major amount of bleeding is expected with bone
replacement surgery and should not be considered as hemorrhage unless
bleeding is particularly excessive.30,31 This bleeding may or may not
be anemia; a code for anemia should be assigned only when the anemia is
documented by the physician.32 Mention of blood loss following surgery
or administration of a blood transfusion during or after surgery are not
necessarily indications that anemia is present. The DRGs identified in
Table 7, below, should be reviewed for documentation supporting the
presence of code 285.1, Acute hemorrhagic anemia.
Summary and Recommendations
As can be seen, ICD-9-CM coding is
a complex process. In order to code accurately, coders must be able to
remember and apply ICD-9 coding principles, and possess a good understanding
of disease processes and medical terminology. Coders must be able to synthesize
documented information about an entire case in order to code accurately.
The documentation related to the inpatient stay should be complete before
the record is coded. That is, coders should have access to the discharge
summary, operative records and pathology reports, and other relevant data
prior to the coding process. Quality of coded data is jeopardized when
coding takes place in the absence of these documents. The coders must
also know when it is appropriate to query physicians if there is doubt
about code assignment.
Continuing education of both the coding
staff and the medical staff cannot be overemphasized. Make physicians
aware of how their documentation of the patients' illnesses affects coding,
especially in view of the recent compliance initiatives. They can improve
their documentation practices by:
- clearly stating manifestations
of Diabetes Mellitus
- differentiating between Diabetes
Mellitus Type I and Diabetes Mellitus Type II. If the latter condition
requires insulin, it should be noted as Diabetes Mellitus, Type II,
insulin requiring (as opposed to insulin dependent)
- showing any existing relationships
between hypertensive disease, congestive heart failure, and renal failure
- fully documenting exacerbations
- identifying the vessel affected
as either native or grafted, autogolous or non-autogolous, and/or vein
or artery graft material used, when a diagnosis of coronary atherosclerosis
- indicating the side affected-dominant
or non-dominant-when hemiplegia occurs following a stroke
- clearly distinguishing between
traumatic and pathological fractures when diagnosing hip fractures,
especially in the elderly
- clearly documenting complications
of medical and surgical care
From review of the 1995 Medicare data,
an in-service should be provided to coders in the following areas:
- sequencing rules for coding signs
- coding to the highest level of
specificity as reflected by physician documentation
- understanding the difference between
Types I and II Diabetes Mellitus
- assigning correct codes for CHF
due to hypertension and CHF and chronic renal failure due to hypertension
- knowing when to code 427.5, Cardiac
- differentiating between traumatic
and pathologic fractures, especially in the elderly
- knowing when to assign complication
In today's pressure-filled healthcare
environment, we sometimes find ourselves coding "for the moment"-that
is, getting the record coded and billed as quickly as possible. But it
is important to keep in mind that the codes submitted will affect future
payment schedules, research databases, and reporting the incidence of
disease to the public, to name a few. As health information managers,
it should be our priority to submit the highest-quality data possible.
- Center for Healthcare Industry
Performance Studies. DRG Resource Book: Data for Benchmarking and Analysis.
Reston, VA: St. Anthony Publications, Inc., 1997.
- American Hospital Association.
Guideline 1.2. AHA Coding Clinic for ICD-9-CM 3, no. 1 (1986): 5.
- Brown, Faye. ICD-9-CM Coding Handbook, revised ed. Chicago, IL: American Hospital Association, 1997,
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 15, no. 3 (1997): 15.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 8, no. 2 (1991): 3.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 13, no. 2 (1996): 10.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 5, no. 3 (1988): 5.
- Ibid, p. 3-4.
- Brown, p. 110.
- American Hospital Association. Guideline 2.2. AHA Coding Clinic for ICD-9-CM 7, no. 2 (1990): 3-4.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 8, no. 1 (1991): 14.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 13, no. 2 (1996): 10.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 13, no. 4 (1996): 36.
- American Hospital Association. Guidelines 4.3 and 4.4. AHA Coding Clinic for ICD-9-CM 7, no. 3 (1990):
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 12, no. 3 (1995): 8-9.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 8, no. 2 (1991): 6
- Brown, p. 203.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 10, no. 4 (1993): 25-26.
- American Hospital Association. Guideline 2.1. AHA Coding Clinic for ICD-9-CM 7, no. 2 (1990): 3-4.
- American Hospital Association. Guideline 2.8. AHA Coding Clinic for ICD-9-CM 7, no. 2 (1990): 5-7.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 10, no. 5 (1993): 7.
- Brown, p. 356.
- Brown, p. 358.
- Brown, p. 359.
- Brown, p. 358.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 9, no. 2 (1992): 15-16.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 10, no. 4 (1993): 34.
- American Hospital Association. AHA Coding Clinic for ICD-9-CM 9, no. 2 (1992): 15-16.
Table 1*—DRG 462, principal diagnosis code assignment with 342.90, Hemiplegia,
*Source: DRG Resource Book, p. 280.
Late Effect of CVA
|Percent of DRG Total
V57.89—Rehab procedure NEC
V57.1—Physical therapy NEC
V57.9—Rehab procedure NOS
V57.21—Encounter for occupational therapy
V57.22—Encounter for vocational therapy
Table 2*—DRG 87, Pulmonary edema and respiratory failure
*Source: DRG Resource Book, p. 44.
Obstructive Chronic Bronchitis with Acute Exacerbation
|401.9 Hypertension NOS
||Percent of DRG Total
|518.4—Acute lung edema NOS
|518.4—Post-traumatic pulmonary insufficiency
|506.1—Fumes/vapor acute pulmonary edema
Table 3*—DRG 429, Mental disease and disorders
*Source: DRG Resource Book, p. 272.
331.0 Alzheimer’s Disease
Percent of DRG Total
|290.0—Senile dementia, uncomplicated
|294.8—Organic brain syndrome, NEC
|293.83—Organic affective syndrome
Table 4*—selected DRGs for pathological/traumatic fractures
*Source: DRG Resource Book, pp. 185, 189, 201, 205.
||Principal DX Codes
||Type of DRG
|209—Major joint and limb reattachment procedures of lower extremity
715.96, 820.09, 715.36, 715.95, 820.8
|210—Hip and femur procedures except major joint procedures, age greater
than 17 with CC
820.21, 820.09, 820.8, 820.22, 821.33
|236—Fractures of the hip and pelvis
808.2, 820.8, 820.21, 820.09, 808.0
|239—Pathological fractures and musculoskeletal and connective tissue malignancy
733.13, 198.5, 733.19, 733.14, 733.15
|243—Medical back problems
805.4, 805.2, 724.2, 722.10, 724.02
Table 5*—Chest pain, 786.xx, in DRGs 125 and 143
*Source: DRG Resource Book, pp. 108, 144.
||Percent of DRG Total
||Percent of DRG Total
Table 6*—use of codes from category 997 as principal diagnosis
*Source: DRG Resource Book, pp. 176, 240, 288
|997.1—Surgical complication, heart (3.6% of cases in DRG)
||477—Nonextensive OR procedure unrelated to principal diagnosis
||428.0, CHF (?) - 13.6%
427.31, Atrial Fibrillation—19.8%
|997.2—Surgical complication, peripheral vascular complication (3.2% of
cases in DRG)
||130—Peripheral vascular disorders with CC
||686.2, cellulitis (?)—0.9%
|997.4—Surgical complication, digestive system (14.8% of cases in DRG)
||188—Other digestive diagnoses, age > 17, with CC
|997.5—Surgical complication, urinary tract (2.7% of cases in DRG)
||477—Nonextensive OR procedure unrelated to principal diagnosis
|997.5—Surgical complication, urinary tract (6.5% of cases in DRG)
||331—Other kidney and urinary tract diagnoses, age > 17, with CC
Table 7*—use of Code 285.1, Acute hemorrhagic anemia, in surgical DRGs
||Principal Diagnosis Codes within DRG
||Percent Cases with Code 285.1
|107—Coronary bypass without CC
|110—Major cardiovascular procedures with CC
|148—Major small and large bowel procedures with CC
|154—Stomach, esophageal, and duodenal procedures, age >
17, with CC
|209—Major joint and reattachment procedures of lower extremity
|210—Hip and femur procedures except major joint procedures,
age > 17, with CC
|214—Back and neck procedures with CC
Carol E. Osborn, PhD, RRA, is an assistant professor, Health Information Management and Systems Division,
at the Ohio State University in Columbus, OH. Within AHIMA, she is the
past chair for the Assembly on Education and a member of the Joint Committee
on Education and the panel of accreditation site visitors.
*Source: DRG Resource Book, pp.
68, 72, 152, 156, 188, 192, 196.
Osborn, Carol E. "Benchmarking with National ICD-9-CM Coded Data." Journal of AHIMA 70, no.3 (1999): 59-69.