Feature / HRG4 continued: chapters K-M

K Endocrine and metabolic system

This chapter covers the endocrine and the metabolic systems. The endocrine system incorporates glands that produce and release hormones (such as insulin, growth hormone and adrenaline) that evoke responses in other cells within the body, helping to regulate metabolism, growth, tissue function and mood. The major glands include the pineal gland, pituitary gland, thyroid gland, thymus, adrenal gland, pancreas, ovary and testes. One of the key areas covered in the chapter is the treatment of diabetes. The metabolic system is responsible for the metabolism of carbohydrates, lipids, proteins, water and nucleic acids, with imbalances leading to various syndromes and diseases.

The chapter is divided into three sub-chapters covering: KA (endocrine system disorders), KB (diabetic medicine) and KC (metabolic disorders). As with other chapters, the number of HRGs has increased compared with version 3.5. There are now 35 different HRGs compared with just 23 in version 3.5, with the HRGs evenly split among the three sub-chapters (12 to cover endocrine disorders, 10 for diabetes and 13 for metabolic disorders).

The endocrine disorder HRGs are structured by gland, with different HRGs for major and minor thyroid procedures and separate groupings for parathyroid and adrenal procedures and for anterior pituitary disorders. The diabetes sub-chapter is effectively grouped by HRGs for diabetes, with hyperglycaemic (high blood glucose) disorders and hypoglycaemic disorders (low blood glucose) and diabetes with lower limb complications. The metabolic disorders group into disorders concerned with electrolyte, fluid and nutrition, with separate groups for inborn errors of metabolism.

The growth in HRGs is a result of improved complication and comorbidity (CC) splits and better splits based on patient age. For the endocrine system disorders, a number of HRGs are split by either with or without CCs. The diabetes HRGs covering hypoglycaemic disorders are split by age (69 and below and 70 and above). The hyperglycaemic HRGs are additionally split by CC, with a three-way split for each age group by major, intermediate and without CC. The metabolic disorders are also subject to three-way CC splits.

The addition of a diagnosis code can help the accuracy of the HRG assignment. For instance, a total thyroidectomy (OPCS B081) would generally group to the HRG root KA01 (major thyroid procedures). But the inclusion of a diagnosis code A490 (staphylococcal infection, unspecified) more accurately defines the case as KA01A (major thyroid procedures with CC).

There were nearly 76,000 finished consultant episodes carried out in this chapter in the first half of 2006, according to analysis by the NHS Information Centre. The main contributors to this total were: KC04Z (inborn errors of metabolism), which accounted for 13,500 and KB02E (diabetes with hyperglycaemic disorders 69 years and under with intermediate CC) at nearly 6,000. KC02B (fluid disorders 70 years and over with intermediate CC) is also one of the higher volume HRGs at 5,400 FCEs over six months.

L Urinary tract and male reproductive system

This chapter covers the urinary tract, which includes the organs of the body that produce and discharge urine (kidneys, ureters, bladder and urethra), and the male reproductive system. The chapter is arranged into three sub-chapters: LA (renal procedures and disorders), LB (urological and male reproductive system procedures and disorders) and LC (renal dialysis unbundled HRGs).

With 122 different HRGs in the chapter, the numbers have doubled compared with the corresponding chapter in version 3.5. And in terms of activity it is the second-biggest chapter within HRG4. Between April and September 2006, nearly 890,000 FCEs were undertaken that would have been assigned an HRG within sub-chapters LA and LB. Only chapter F, covering the digestive system, has more activity. (In addition, IC analysis shows that there were an additional 350,000 reported occurrences of renal dialysis during the same monitored period, with almost 98% of them grouping to LC02A (haemodialysis/ filtration 19 years and over).

The chapter captures far more detail with additional HRGs, improved complication and comorbidity (CC) splits, paediatric age splits plus the unbundled HRGs for renal dialysis. For instance, there are six HRGs for a kidney transplant instead of one. This recognises that patients receiving a kidney from a cadaver generally experience more complications than those that receive from a live donor and so consume more resources. There are also separate groups to recognise the further complications of transplanting from a cadaver whose heart is no longer beating. There are additional splits for the patient’s age.

There are three levels of CC splits within the LA and LB sub-chapters (without CC, intermediate CC and major CC) with particular use made of them to distinguish severity level of medical patients with the same primary diagnosis. Paediatric age splits also help the granularity. Within the renal sub-chapter, a length of stay split has been added to the chronic renal failure HRG to separate those who stay in for fewer than two days from those who stay longer.

New OPCS codes covering the specialised work-up and follow-up activities for kidney donors and recipients, if used, can help map to a more specific HRG (LA11Z to LA14Z). Within the urological and male reproductive system sub-chapter, there is a new HRG for unspecified haematuria (blood in urine). Previously, the relevant ICD-10 code for this diagnosis mapped to the old HRG L55 for urinary tract findings. But because of the volumes involved this was distorting the costs of that HRG. Some 80 new codes within OPCS-4.3, covering urological procedures, have also helped improve the accuracy of grouping.

There are new HRGs for laparoscopic operations and two new HRGs for activity that under version 3.5 would have been assigned to a non-specific chapter S HRG. In addition, rigid cystoscopy has now been separated from flexible cystoscopy, with the rigid cystoscopy mapping to an intermediate bladder procedure rather than a minor one.

There are eight HRGs within the renal dialysis sub-chapter. This is a fourfold increase on HRGs within version 3.5, which simply covered renal replacement therapy with and without CC. This greater specificity in particular means that a distinction can be made between peritoneal dialysis (given daily) and haemodialysis (two to four times a week). The HRGs are also unbundled, meaning that a renal dialysis HRG is assigned in addition to a core or main HRG.

Across the LA and LB sub-chapter, one HRG accounts for more than 40% of all finished consultant episodes activity (383,250 procedures over half of 2006) – LA08D (chronic renal failure with length of stay 1 day or less).This is likely to be the core HRG for the unbundled renal dialysis HRGs in sub-chapter LC, hence the similarity in activity levels. There are, however, other significant contributors to the overall activity. LB15C (bladder minor procedure 19 years and over without CC) accounted for more than 110,000 FCEs and the same procedure with intermediate CC added more than a further 30,000 episodes.

Using diagnosis codes to supplement the information in procedure codes can help refine the grouping. For instance, a procedure code of X401 for renal dialysis usually maps to LC02A (haemodialysis/ filtration 19 years and over). But with a secondary diagnosis of hepatitis B – for example, B161 acute hepatitis B with delta-agent (coinfection) without hepatic coma – the patient will group to LC01A (haemodialysis/filtration on patient with hepatitis B 19 years and over).

M Female reproductive system and assisted reproduction

This chapter includes all gynaecology procedures (diagnostics and treatment by endoscopy, open surgery, non-invasive and other methods) and gynaecology disorders. The chapter also covers in-vitro fertilisation (IVF).

The basic structure of the chapter is the same as for version 3.5, with the use of major, intermediate and minor to distinguish the complexity of different procedures. There have, however, been a number of improvements. For instance, additional HRGs have been created to cover very complex procedures and those using a laparoscopic/endoscopic approach.

Paediatric age splits have been introduced for two HRGs. There was no HRG that accurately represented IVF under version 3.5. Various types of IVF, however, are now covered and the termination of pregnancy HRGs include gestation splits to reflect resource more accurately. The addition of 40 procedure codes as part of the updating of OPCS procedure classifications has allowed for greater detail to be captured on laparoscopic procedures.

These changes have led to a doubling of HRGs in the chapter compared with version 3.5. The 42 HRGs are spread across three sub-chapters: MA (female reproductive system procedures), MB (female reproductive system disorders) and MC (assisted reproduction medicine).

In the six months to September 2006, some 297,000 finished consultant episodes would have mapped to this chapter. The high-volume contributors include: MA13B (upper genital tract minor procedures 19 years and over without CC) at 45,000 FCEs; MA05B (lower genital tract minor procedures without CC) at 34,000; and MB08A (threatened or spontaneous miscarriage 19 years and over) at nearly 36,000.

Intra-uterine insemination (previously referred to as artificial insemination) and IVF treatments within the NHS remain low-volume activities, with fewer than 600 FCEs in the whole sub-chapter for the six-month period monitored by the IC.

Where a significant procedure has taken place, the HRG is derived from the dominant procedure. Where there is no procedure deemed significant enough for grouping, the HRG is driven by the primary diagnosis. Even with a procedure, however, diagnosis can influence the final HRG. For instance, a procedure code of P171 for a total colpectomy usually maps to MA03B (lower genital tract major procedure without CC). However, the inclusion of a malignancy diagnosis (for example, C542 – malignant neoplasm of myometrium) groups the episode to MA06Z (open major upper and lower genital tract procedures with malignancy).