Improving the Measurement of Surgical Site Infection Risk Stratification/Outcome Detection

Background

Administrative coding is different in the VA than at some other institutions. CPT codes are relied on more frequently. NSQIP, a program that started in the VA relies on CPT codes. Sampling surgeries based on ICD9 alone in the VA may lead to unrepresentative samples. Good mappings between ICD9 and CPT codes are still incomplete, so we made our independent attempt.

Method

We used the UMLS (Unified Medical Language System) metathesaurus concepts to bridge between ICD9 and CPT vocabularies at the level of coronary artery bypass grafting (CABG), herniorrhaphies, procedures of the hip, and procedures of the distal femur and knee. We then reviewed the children of these concepts and identified codes which described the types of procedures which were included in the ICD9 list. We felt that this procedure was more reproducible and updatable than a bottom-up approach.

Results

The following graph shows the number of procedures per month identified by type.

CABG = coronary artery bypass graft, HPRO = hip arthroplasty, KPRO = knee arthroplasty, HER = herniorrhaphy.

Text Description:

Graph detailing Salt Lake City Veterans Administration surgical procedures by type, reported quarterly for Federal fiscal years 2005 – 2009. Procedures include: coronary artery bypass graft (CABG), hip arthroplasty (HPRO), knee arthroplasty (KPRO), and herniorrhaphy (HER). 1Q–4Q = first through fourth quarters of the noted fiscal year.
1Q 2005: CABG 42, HPRO 14, KPRO 38, HER 54.
2Q 2005: CABG 90, HPRO 25, KPRO 25, HER 47.
3Q 2005: CABG 53, HPRO 22, KPRO 35, HER 48.
4Q 2005: CABG 64, HPRO 20, KPRO 22, HER 62.
1Q 2006: CABG 49, HPRO 16, KPRO 52, HER 43.
2Q 2006: CABG 50, HPRO 21, KPRO 60, HER 63.
3Q 2006: CABG 41, HPRO 24, KPRO 39, HER 58.
4Q 2006: CABG 33, HPRO 25, KPRO 59, HER 71.
1Q 2007: CABG 16, HPRO 39, KPRO 27, HER 48.
2Q 2007: CABG 26, HPRO 30, KPRO 32, HER 53.
3Q 2007: CABG 74, HPRO 36, KPRO 41, HER 45.
4Q 2007: CABG 48, HPRO 34, KPRO 66, HER 67.
1Q 2008: CABG 30, HPRO 34, KPRO 60, HER 39.
2Q 2008: CABG 41, HPRO 25, KPRO 80, HER 43.
3Q 2008: CABG 54, HPRO 33, KPRO 89, HER 31.
4Q 2008: CABG 22, HPRO 37, KPRO 72, HER 48.
1Q 2009: CABG 23, HPRO 36, KPRO 91, HER 49.
2Q 2009: CABG 40, HPRO 27, KPRO 81, HER 38.
3Q 2009: CABG 21, HPRO 25, KPRO 45, HER 58.
4Q 2009: CABG 31, HPRO 21, KPRO 44, HER 30.

We also examined the VA database to determine how well ICD9 and CPT codes match each other for these procedures during this time period. For simplification, the numbers in the tables below identified unique patients — assuming that reoperation was rare. ICD9 and CPT for the same surgery type intersected or coincided if they were documented within a week of each other. They were listed in disagreement if the time between them was greater. As can be seen in the tables below, ICD-9 alone identified >95% of CABG, hip and knee arthroplasties. Herniorrhaphies did not fare as well with 77.7% being identified by CPT only.

Coronary Artery Bypass Grafting (CABG)

Scripts containing ICD9 procedural and CPT codes that we used to identify CABG are listed below. We queried by ICD9 alone, by CPT alone and on the intersection of the two. Results are shown in the following table.

CABG with veinous grafts or arterial and venous grafts

WHERE ICD9P IN (36.10,36.11,36.12,36.13,36.14,36.19)
36.10 Aortocoronary bypass for heart revascularization, not otherwise specified
36.11 (Aorto)coronary bypass of one coronary artery
36.12 (Aorto)coronary bypass of two coronary arteries
36.13 (Aorto)coronary bypass of three coronary arteries
36.14 Aorto)coronary bypass of four or more coronary arteries
36.19 Other bypass anastomosis for heart revascularization

OR (CPT BETWEEN '33510' AND '33514')
33510 coronary artery bypass, vein only; single coronary venous graft
33511 2 coronary venous grafts
33512 3 coronary venous grafts
33513 4 coronary venous grafts
33514 5 coronary venous grafts

OR (CPT BETWEEN '33516' AND '33519')
33516 Coronary artery bypass, vein only; 6 or more coronary venous grafts
33517 Coronary artery bypass, using venous graft(s) and arterial graft(s); single vein graft
33518 Coronary artery bypass, using venous graft(s) and arterial graft(s); 2 venous grafts
33519 Coronary artery bypass, using venous graft(s) and arterial graft(s); 3 venous grafts

OR (CPT IN (33521,33522,33523))
33521 4 venous grafts
33522 5 venous grafts
33523 6 or more venous grafts

CABG with only arterial grafts

WHERE ICD9P IN (36.15,36.16,36.17,36.20)
36.15 Single internal mammary-coronary artery bypass
36.16 Double internal mammary-coronary artery bypass
36.17 Abdominal - coronary artery bypass
36.19 Other bypass anastomosis for heart revascularization
36.20 Heart revascularization by arterial implant

OR (CPT BETWEEN '33533' AND '33536')
33533 Coronary artery bypass, using arterial graft(s); single arterial graft
33534 2 coronary arterial grafts
33535 3 coronary arterial grafts
33536 4 or more coronary arterial grafts

Herniorrhaphies

Scripts containing ICD9 procedural and CPT codes that we used to identify herniorrhaphies are listed below. We queried by ICD9 alone, by CPT alone and on the intersection of the two. Results are shown in the following table.

WHERE ICD9P IN (17.11,17.12,17.13,17.21,17.22,17.23,17.24,53.00,53.01,53.02,53.03,53.04,53.05,53.10,53.11,53.12,53.13,53.14,53.15,53.16,53.17,
53.21,53.29,53.31,53.39,53.41,53.42,53.43,53.49,53.51,53.59,53.61,53.62,53.63,53.69)
17.11 Laparoscopic repair of direct inguinal hernia with graft or prosthesis Laparoscopic repair of direct and indirect inguinal hernia with graft or prosthesis
17.12 Laparoscopic repair of indirect inguinal hernia with graft or prosthesis
17.13 Laparoscopic repair of inguinal hernia with graft or prosthesis, not otherwise specified
17.21 Laparoscopic bilateral repair of direct inguinal hernia with graft or prosthesis
17.22 Laparoscopic bilateral repair of indirect inguinal hernia with graft or prosthesis
17.23 Laparoscopic bilateral repair of inguinal hernia, one direct and one indirect, with graft or prosthesis
17.24 Laparoscopic bilateral repair of inguinal hernia with graft or prosthesis, not otherwise specified
53.00 Unilateral repair of inguinal hernia, not otherwise specified Inguinal herniorrhaphy NOS
53.01 Other and open repair of direct inguinal hernia Direct and indirect inguinal hernia
53.02 Other and open repair of indirect inguinal hernia
53.03 Other and open repair of direct inguinal hernia with graft or prosthesis
53.04 Other and open repair of indirect inguinal hernia with graft or prosthesis
53.05 Repair of inguinal hernia with graft or prosthesis, not otherwise specified
53.10 Bilateral repair of inguinal hernia, not otherwise specified
53.11 Other and open bilateral repair of direct inguinal hernia
53.12 Other and open bilateral repair of indirect inguinal hernia
53.13 Other and open bilateral repair of inguinal hernia, one direct and one indirect
53.14 Other and open bilateral repair of direct inguinal hernia with graft or prosthesis
53.15 Other and open bilateral repair of indirect inguinal hernia with graft or prosthesis
53.16 Other and open bilateral repair of inguinal hernia, one direct and one indirect, with graft or prosthesis
53.17 Bilateral inguinal hernia repair with graft or prosthesis, not otherwise specified
53.21 Unilateral repair of femoral hernia with graft or prosthesis
53.29 Other unilateral femoral herniorrhaphy
53.31 Bilateral repair of femoral hernia with graft or prosthesis
53.39 Other bilateral femoral herniorrhaphy
53.41 Other and open repair of umbilical hernia with graft or prosthesis
53.42 Laparoscopic repair of umbilical hernia with graft or prosthesis
53.43 Other laparoscopic umbilical herniorrhaphy
53.49 Other open umbilical herniorrhaphy
53.51 Incisional hernia repair
53.59 Repair of other hernia of anterior abdominal wall
53.61 Other open incisional hernia repair with graft or prosthesis
53.62 Laparoscopic incisional hernia repair with graft or prosthesis
53.63 Other laparoscopic repair of other hernia of anterior abdominal wall with graft or prosthesis
53.69 Other and open repair of other hernia of anterior abdominal wall with graft or prosthesis

OR CPT IN (49505, 49507, 49520, 49521, 49525, 49550, 49553, 49555, 49560, 49561, 49565, 49566, 49568, 49580, 49582, 49585, 49587)
49505 Repair initial inguinal hernia, age 5 years or over; reducible
49507 Repair initial inguinal hernia, age 5 years or older;incarcerated or strangulated
49521 Repair recurrent inguinal hernia, any age;incarcerated or strangulated
49525 Repair inguinal hernia, sliding, any age
49550 Repair initial femoral hernia, any age; reducible
49553 Repair initial femoral hernia, any age;incarcerated or strangulated
49555 Repair recurrent femoral hernia; reducible
49560 Repair initial incisional or ventral hernia; reducible
49561 Repair initial incisional or ventral hernia;incarcerated or strangulated
49565 Repair recurrent incisional or ventral hernia; reducible
49566 Repair recurrent incisional or ventral hernia; incarcerated or strangulated
49568 Implantation of mesh or other prosthesis for open incisional or ventral hernia repair or mesh for closure of debridement for necrotizing soft tissue infection
49580 Repair umbilical hernia, under age 5 years; reducible
49582 Repair umbilical hernia, younger than age 5 years; incarcerated or strangulated
49585 Repair umbilical hernia, age 5 years or over; reducible
49587 Repair umbilical hernia, age 5 years or older; incarcerated or strangulated

OR (CPT BETWEEN '49650' AND '49657')
49650 Laparoscopy, surgical; repair initial inguinal hernia
49651 Laparoscopy, surgical;repair recurrent inguinal hernia
49652 Laparoscopy, surgical, repair, ventral, umbilical, spigelian or epigastric hernia (includes mesh insertion, when performed); reducible
49653 Laparoscopy, surgical, repair, ventral, umbilical, spigelian or epigastric hernia (includes mesh insertion, when performed); Incarcerated or strangulated
49654 Laparoscopy, surgical, repair, incisional hernia (includes mesh insertion, when performed); reducible
49655 Laparoscopy, surgical, repair, incisional hernia (includes mesh insertion, when performed); incarcerated or strangulated
49656 Laparoscopy, surgical, repair, recurrent incisional hernia (includes mesh insertion, when performed); reducible
49657 Laparoscopy, surgical, repair, recurrent incisional hernia (includes mesh insertion, when performed) ;incarcerated or strangulated

Hip Arthroplasties

Scripts containing ICD9 procedural and CPT codes that we used to identify hip arthroplasties are listed below. We queried by ICD9 alone, by CPT alone and on the intersection of the two. Results are shown in the following table.

WHERE ICD9P IN (00.70,00.71,00.72,00.73,00.85,00.86,00.87,81.51,81.52,81.53)
00.70 Other hip procedures
00.71 Revision of hip replacement, acetabular component
00.72 Revision of hip replacement, femoral component
00.73 Revision of hip replacement, acetabular liner and/or femoral head only
00.85 Resurfacing hip, total, acetabulum and femoral head
00.86 Resurfacing hip, partial, femoral head
00.87 Resurfacing hip, partial, acetabulum
81.51 Total hip replacement
81.52 Partial hip replacement
81.53 Revision of hip replacement, not otherwise specified

OR (CPT IN (27130,27132,27134,27137,27138))
27130 Arthroplasty, acetabular and proximal femoral prosthetic replacement (total hip arthroplasty), with or without autograft or allograft
27132 Conversion of previous hip surgery to total hip arthroplasty, with or without autograft or allograft
27134 Revision of total hip arthroplasty; both components, with or without autograft or allograft
27137 Revision of total hip arthroplasty; acetabular component only, with or without autograft or allograft
27138 Revision of total hip arthroplasty; femoral component only, with or without allograft

Knee Arthroplasties

Scripts containing ICD9 procedural and CPT codes that we used to identify knee arthroplasties are listed below. We queried by ICD9 alone, by CPT alone and on the intersection of the two. Results are shown in the following table.

WHERE ICD9P IN (00.80,00.81,00.82,00.83,00.84,81.54,81.55)
00.80 Revision of knee replacement, total (all components)
00.81 Revision of knee replacement, tibial component
00.82 Revision of knee replacement, femoral component
00.83 Revision of knee replacement, patellar component
00.84 Revision of total knee replacement, tibial insert (liner)
81.54 Total knee replacement
81.55 Revision of knee replacement, not otherwise specified

OR (CPT BETWEEN '27440' AND '27447')
27440 Arthroplasty, knee, tibial plateau;
27441 Arthroplasty, knee, tibial plateau;with debridement and partial synovectomy
27442 Arthroplasty, femoral condyles or tibial plateau(s), knee;
27443 Arthroplasty, femoral condyles or tibial plateau(s), knee;with debridement and partial synovectomy
27445 Arthroplasty, knee, hinge prosthesis (eg, Walldius type)
27446 Arthroplasty, knee, condyle and plateau; medial OR lateral compartment
27447 Arthroplasty, knee, condyle and plateau; medial AND lateral compartments with or without patella resurfacing

OR (CPT IN (27486,27487))
27486 Revision of total knee arthroplasty, with or without allograft; 1 component
27487 Revision of total knee arthroplasty, with or without allograft; femoral and entire tibial component

Conclusion

Herniorrhaphies cannot be identified by ICD9 procedure codes alone in the VA. For the other surgeries, this may give an acceptable result. However, we recommend that the combined set of ICD9 and CPT codes be used for all procedures in the VA to identify surgeries of interest.