Abstract

BACKGROUND: Gynaecological laparotomies are associated with considerable adhesion-related burdens; however, few data are available concerning laparoscopic surgery. This study evaluated the epidemiology of adhesion-related readmissions following open and laparoscopic procedures. METHODS: Records from 24 046 patients undergoing gynaecological surgery in Scottish National Health Service hospitals during 1996 were assessed retrospectively. Cohorts comprised 15 197 patients undergoing laparoscopic surgery and 8849 patients undergoing laparotomies. Adhesion-related readmission episodes (directly and possibly related) were assessed over 4 years following initial surgery and were expressed as percentages of the number of initial procedures. RESULTS: Directly adhesion-related readmissions 1 year after initial laparoscopic surgery were: in the high-risk group (adhesiolysis and cyst drainage) 1.3%; medium-risk (therapeutic and diagnostic procedures not categorized as high- or low-risk) 1.5%; and low-risk (Fallopian tube sterilizations) 0.2%. Readmissions for laparotomy following surgery on the Fallopian tubes were 0.9%, ovaries 2.1%, uterus 0.6% and vagina 0%. Readmissions occurred at reduced rates in the second, third and fourth years after surgery. Exclusion of patients who underwent surgery within the previous 5 years resulted in reduced readmission rates following laparotomy and high-risk laparoscopy. CONCLUSIONS: With the exception of laparoscopic sterilizations, open and laparoscopic gynaecological surgery are associated with comparable risks of adhesion-related readmissions.

Introduction

Post-surgical adhesions are a widespread and largely unacknowledged problem that represent a considerable burden to patients in terms of re-operations ( Ivarsson et al. , 1997 ), and perioperative and postoperative complications such as enterotomy ( van der Krabben et al. , 2000 ), small bowel obstruction ( Ellis, 1998 ), chronic pelvic pain ( Howard, 1993 ; Duffy and diZerega, 1996 ) and infertility ( Monk et al. , 1994 ; Liakakos et al. , 2001 ). The readmission of many patients to hospital for adhesion-related complications also places a considerable burden on surgeons and health-care providers in terms of bed space, health-care costs ( Ivarsson et al. , 1997 ; Ray et al. , 1998 ; Beck et al. , 2000 ; Menzies et al. , 2001 ), extended theatre times ( Beck et al. , 2000 ; Coleman et al. , 2000 ), more complex surgical procedures ( Beck et al. , 2000 ; van der Krabben et al. , 2000 ) and added pressure on waiting lists.

Post-surgical adhesions form as a result of a range of insults (such as surgical trauma, infection, ischaemia, and exposure to intestinal contents and foreign materials) that disrupt the peritoneum and cause inflammation ( Diamond and Freeman, 2001 ). Adhesion development begins during surgery and proceeds rapidly. Re-epithelialization is achieved within 5–7 days and adhesion formation follows if damaged surfaces remain in apposition ( Holmdahl et al. , 1997 ; diZerega and Campeau, 2001 ).

Corrective surgery is often required to resolve adhesion-related complications; however, additional surgery tends to encourage the development of additional (de-novo) adhesions and the reformation of lysed adhesions ( Beck et al. , 2000 ). As many as 93% of patients undergoing laparotomies develop adhesions attributable to earlier surgery ( Menzies and Ellis, 1990 ) and up to 85% of adhesions reform following adhesiolysis ( Diamond and Freeman, 2001 ). Furthermore, reformed adhesions tend to be denser and more severe than de-novo adhesions ( van der Krabben et al. , 2000 ).

With the increasing use of surgery to treat gynaecological conditions (particularly infertility), adhesions now represent a growing problem for gynaecologists ( Lower et al. , 2000 ). Intra-abdominal adhesions occur in 60–90% of women who have undergone major gynaecological procedures and account for 15–20% of cases of secondary infertility ( Mishell and Davajan, 1991 ; Liakakos et al. , 2001 ). They are also associated with substantial morbidity, constituting one of the most common causes of pelvic pain in women ( Mishell and Davajan, 1991 ; Howard, 1993 ; Duffy and diZerega, 1996 ; Diamond and Freeman, 2001 ). Furthermore, initial surgery in one region may result in adhesions in another, such that women undergoing gynaecological procedures may develop adhesive small bowel obstruction ( Lower et al. , 2000 ).

The Surgical and Clinical Adhesions Research (SCAR) study was an epidemiological study that investigated the burden of post-surgical adhesions by analysing hospital readmissions in Scottish National Health Service (NHS) patients ( n =54–380) within the 10 years following initial open abdominopelvic surgery during 1986. The study included an assessment of the impact of adhesions following initial open gynaecological surgery in a cohort of 8849 women ( Ellis et al. , 1999 ; Lower et al. , 2000 ). The results demonstrated clearly that the clinical burden, workload and relative risk of hospital readmissions associated with post-surgical adhesions were considerable. In total, more than one in three women were readmitted on average 1.9 times during the 10-year follow-up for further surgery or for problems potentially related to adhesions ( Lower et al. , 2000 ).

Whilst the SCAR study demonstrated clearly the burden of adhesions associated with open gynaecological surgery, data concerning the impact of adhesions following gynaecological laparoscopy are lacking. Laparoscopic surgery was in its infancy in 1986 and was used primarily as a diagnostic, rather than a therapeutic, procedure. Since then, laparoscopy has become the preferred method of access for certain gynaecological interventions, and has been claimed to be associated with lower rates of adhesion development ( Garrard et al. , 1999 ; Kavic, 2002 ). The objective of this study was to compare the epidemiology of adhesion-related readmissions in the 4 years following initial open surgery with that following initial laparoscopic gynaecological surgery.

Methods

This study used validated patient records from the Scottish NHS Medical Record Linkage database, chosen because of its size, completeness and quality of data. The database holds one of the largest patient-linked data sets available and allows tracking of all hospital inpatient and day-case admissions in Scotland from 1981. The database is managed by the Scottish NHS Information and Statistics Division (ISD), which uses stringent quality control to ensure 99% accuracy in the linkage of patient records. Scotland provides a stable, geographically contained population ( n =5.1 million) with a low annual migration rate (<1%) ( Office for National Statistics, 2003 ).

Office of Population Censuses and Surveys', Fourth Edition (OPCS4) surgical procedure codes were identified in duplicate by members of the study steering group to determine open and laparoscopic gynaecological procedures (excluding Caesarean sections) that were likely to cause adhesions ( Government Statistical Service, 2001 ). Based on these codes, two incident patient cohorts were defined within the database, comprising those undergoing initial laparoscopic gynaecological surgery ( n =15 197) and those undergoing initial open gynaecological surgery ( n =8849) in the financial year April 1996 to March 1997 (1996–1997). Adhesion-related readmissions were tracked over 4 years following initial surgery.

Initial open surgical procedures were classified by operation site, according to OPCS4 codes, as procedures performed on the Fallopian tubes, ovaries, uterus and vagina. Since OPCS4 codes for the classification of laparoscopic procedures are less specific than those describing open surgery, the laparoscopic cohort was subdivided into procedures associated with high, medium and low risks of adhesion-related readmissions. Laparoscopic adhesiolysis and cyst drainage operations constituted high-risk procedures, Fallopian tube sterilizations were categorized as low-risk procedures, and medium-risk procedures were represented by all other therapeutic and diagnostic laparoscopies (including other tubal procedures) ( Table I ). Most interventions in the medium-risk group (99%) were categorized under code T439: ‘unspecified diagnostic endoscopic examination of the peritoneum’.

Adhesion-related readmissions in patients within the two cohorts were determined using OPCS4 surgical codes and International Classification of Diseases, Tenth Edition (ICD10) ( WHO, Office of Publications, 1992 ) diagnostic codes. Codes were identified individually by two surgeons and any differences were adjudicated by a third. Readmissions were classified, as described previously ( Ellis et al. , 1999 ; Parker et al. , 2001 ), as: ‘directly related to adhesions’ (operative and non-operative codes specifically mentioning adhesions or adhesiolysis, e.g. operative OPCS4 codes: Q341, T413, T428; non-operative ICD10 codes: K565, K660, N994) ( Tables II and III ); ‘possibly related to adhesions’ (codes referring to procedures or diagnoses which could be related to adhesions, but with no defined adhesion code, e.g. operative OPCS4 codes: Q221, T309; non-operative ICD10 codes: R102, R103, R104) ( Tables II and III ); or ‘re-operations (open or laparoscopic) that were unrelated to but potentially complicated by adhesions’ (e.g. OPCS4 codes: Q074, Q432, Q493) (data not shown).

The key outcome measures of the study were 1-year adhesion-related readmission rates and cumulative readmission rates over 4 years. These were determined for all surgical subgroups within the 1996–1997 open and laparoscopic cohorts.

Data were also collected for patients undergoing initial open and laparoscopic surgery in the financial years April 1997 to March 1998 (1997–1998) and April 1998 to March 1999 (1998–1999). Patients were followed up for 2 years and data were compared with the 1996–1997 cohort to identify any variation in readmissions between years and to determine time to first directly/possibly adhesion-related readmission. Where patients had a directly and a possibly related readmission within the same year, only the first event was counted when they were combined, as this was thought to best reflect the time lapse between initial surgery and the first requirement for further treatment. It should be noted that, because only the first event was counted, addition of the directly related and possibly related readmission data does not equal the sum of the directly/possibly related readmission data. The incidences of readmissions in the 3-yearly cohorts were compared using Peto's log-rank test ( Peto et al. , 1977 ).

A final objective was to assess the impact of previous surgery on adhesion-related readmissions by identifying patient subgroups within the 1996–1997 open and laparoscopic cohorts who had had no abdominopelvic surgery within the previous 5 years. To identify these patients, all OPCS4 readmission codes were matched, where possible, to the earlier OPCS3 codes, as coding had changed in 1989 ( Ellis et al. , 1999 ; Lower et al. , 2000 ).

Adhesion-related readmissions in all cohorts are expressed as rates of patient readmission and rates of readmission episodes. Readmission episode rates are presented because some patients were readmitted more than once, and are expressed as a percentage of the total number of initial surgical procedures; the risk of a readmission was calculated from these percentages.

Results

Fallopian tube sterilizations represented the most common indication for gynaecological laparoscopy (59% of all laparoscopies), and were associated with a low risk of directly adhesion-related readmissions within the first year of 1 in 500 (0.2 readmission episodes per 100 patients) ( Table IV ). Laparoscopic adhesiolysis, representing 4% of all laparoscopies, was predefined as high-risk, while the remaining laparoscopic procedures (37% of all laparoscopies) were categorized as medium-risk ( Table IV ). The predetermined high-risk and medium-risk laparoscopic groups carried similar risks of directly adhesion-related readmissions (one in 80, 1.3/100, and one in 70, 1.5/100, respectively), which were considerably greater than those associated with low-risk Fallopian tube sterilizations ( Table IV ). The risks of a possibly adhesion-related readmission within the first year were: high-risk, up to one in 7; medium-risk, up to one in 10; and low-risk, up to one in 40 ( Table IV ).

In the medium- and high-risk laparoscopic subgroups, the combined risk of a directly or possibly related readmission was highest within the first year, although readmissions continued to occur during the second, third and fourth years ( Figure 1 ). The readmission risk remained constant over the 4 years following low-risk procedures.

Open uterine surgery represented the most common form of laparotomy (91% of procedures) and was associated with a low risk of directly adhesion-related readmissions within the first year of one in 170 (0.6 readmission episodes per 100 patients). Open surgical interventions on the ovaries and Fallopian tubes were much less common (4% and 5% of procedures, respectively), but resulted in substantially higher risks of directly adhesion-related readmissions [one in 50 (2.1/100), and one in 120 (0.9/100), respectively]. The risks of a possibly adhesion-related readmission within the first year for the high-, medium- and low-risk groups were approximately one in six, one in seven and one in 20, respectively. The risks of a directly/possibly adhesion-related readmission were highest in the first year in all open surgery categories ( Figure 2 ).

A substantial proportion (16.4%) of patients undergoing high-risk laparoscopic adhesiolysis in 1996–1997 were readmitted within 2 years for a directly or possibly adhesion-related event, while >7% of patients undergoing laparotomies were readmitted within 2 years. Data from the 1997–1998 and 1998–1999 cohorts reflected similar patterns (χ 2 for equivalence of absolute readmission rates=2.04; P =0.36), indicating that little improvement in the rate of adhesion-related readmissions had been achieved ( Figure 3 ).

The exclusion of patients who underwent surgery within the 5 years prior to 1996–1997 had little effect on the overall rate of directly adhesion-related readmissions in the first year following laparoscopy (0.7% for all readmissions versus 0.6% excluding previous surgery), but resulted in a reduction in the readmission rate following laparotomy (0.7% versus 0.3%) ( Tables IV and V ). When high-risk laparoscopy alone was considered, a reduction in the 1-year directly adhesion-related readmission rate was observed (1.3% versus 0.6%) and was maintained over the next 3 years ( Tables IV and V ).

The most common surgical procedure defined as the cause of a directly adhesion-related readmission following initial high-, medium- and low-risk laparoscopic surgery was open surgery for the ‘freeing of adhesions of the peritoneum’ (high risk 75%; medium risk 59%; low risk 50%) ( Table II ). ‘Postprocedural pelvic peritoneal adhesions’ (high-risk group) and ‘peritoneal adhesions’ (medium- and low-risk groups) were the only directly adhesion-related causes of non-operative patient readmission in the laparoscopic cohort and were identified using ICD10 diagnostic codes ( Table II ).

‘Freeing of adhesions of the peritoneum’ represented the most common directly adhesion-related surgical cause of readmission in patients undergoing initial open surgery on the Fallopian tubes, ovaries and uterus ( Table III ). The most common non-operative reason for a directly adhesion-related readmission was ‘intestinal adhesions with obstruction’. None of the patients undergoing initial open surgery on the vagina required readmission for directly adhesion-related operative or non-operative causes ( Table III ).

Discussion

The use of laparoscopy for interventions, as well as diagnoses, has increased considerably over the last decade such that it now represents the predominant form of gynaecological surgery performed in Scotland. It has been suggested that, owing to its less invasive nature, laparoscopy may result in fewer adhesions than laparotomy during comparable surgical interventions ( Garrard et al. , 1999 ; Kavic, 2002 ). Data from the current study support this view with respect to laparoscopic tubal sterilization procedures, which represented a considerable proportion of laparoscopies (59%), and the vast majority of low-risk laparoscopies, and were associated with a low risk of a directly related readmission within the first year of surgery (one in 500). However, for medium- and high-risk laparoscopies, which comprised over 40% of gynaecological laparoscopies, the risks of a directly adhesion-related readmission were considerable (one in 70 and one in 80, respectively) and were substantially higher than for the most common form of gynaecological laparotomy, uterine laparotomy (one in 170).

Some caution is required when interpreting data concerning medium-risk interventions, since these comprised a range of diagnostic procedures that may have identified pre-existing adhesions, adhesion-related problems or conditions associated with the formation of adhesions (such as endometriosis) rather than representing causes of adhesion formation or re-formation. Furthermore, because coding for laparoscopic surgery has lagged behind the rapid advancements in this field, appropriate codes were not available to describe certain therapeutic laparoscopic procedures, resulting in the possible inclusion of therapeutic interventions in this risk group. For these reasons, this category was associated with greater risks of adhesion-related readmissions than might be expected. Further work is required to complete development of appropriate codes for the description of laparoscopic procedures.

OPCS4 surgical codes do not enable direct comparisons to be made between specific open and laparoscopic procedures, because laparoscopic surgical procedures have advanced beyond the limits of the OPCS4 coding system. However, evaluation of the readmission rates associated with high-risk laparoscopy (including many ovarian procedures) compared with ovarian (high-risk) laparotomy provides some indication that laparoscopy is less adhesiogenic. After 4 years, 33.0% of patients undergoing initial high-risk laparoscopy had been readmitted as a result of possibly adhesion-related events, compared with 43.6% of those undergoing initial ovarian laparotomy. However, the higher frequency with which gynaecological laparoscopies are performed may result in a higher overall burden of adhesion-related readmissions, and consequently a greater surgical workload, compared with laparotomy.

Strong evidence is available to suggest that previous laparotomy is a major risk factor for adhesion development and adhesion-related hospital readmissions ( Menzies and Ellis, 1990 ; Ellis et al. , 1999 ; Beck et al. , 2000 ), and the present investigation provides further evidence to support this. Rates of directly adhesion-related readmissions at 1 year following both laparotomy, and particularly high-risk laparoscopy, were reduced and maintained over the following 3 years when patients who underwent surgery within the previous 5 years were excluded. A substantial proportion of high-risk laparoscopic procedures (26.1%) comprised interventions for the ‘endoscopic division of adhesions of the peritoneum’. It is probable that previous surgery represented a major contributory factor in the development of such adhesions, so the exclusion of patients who had undergone surgery within the previous 5 years is likely to have reduced substantially the number of patients requiring this intervention, and thus the proportion of patients requiring hospital readmission for adhesion-related events.

The most common surgical cause of directly adhesion-related readmissions in patients undergoing both initial laparotomy and initial laparoscopy was ‘freeing of adhesions of the peritoneum’, whereas the most common cause in those not proceeding to surgery was ‘intestinal adhesions with obstruction’. It is recognized that surgery on the female reproductive tract can cause adhesion formation at other surgical sites, including the peritoneum and small bowel ( Lower et al. , 2000 ), and the current study supports these conclusions. It is interesting to note that the most common cause of non-operative readmissions possibly related to adhesions in all laparotomy subgroups was ‘unspecified pain’. The association between adhesions and pain is a complex one that remains a subject of debate ( Diamond and Freeman, 2001 ). However, numerous studies have shown a correlation between the presence of adhesions and pelvic pain, and adhesive disease is now considered to be one of the most common causes of chronic pelvic pain in women ( Mishell and Davajan, 1991 ; Howard, 1993 ; diZerega, 1997 ; Diamond and Freeman, 2001 ).

In conclusion, data from the present investigation indicate that gynaecological laparoscopic and open surgical procedures are associated with comparable risks of readmission for adhesion-related problems. The current study is likely to have underestimated the number of directly adhesion-related readmissions because a substantial proportion of patients classified in the ‘possibly adhesion-related’ category may have had directly adhesion-related complications. Furthermore, data from the 1997–1998 and 1998–1999 cohorts show little reduction in the rate of adhesion-related readmissions compared with the 1996–1997 cohort. It should be noted that, whereas the use of adhesion-prevention adjuvants has increased in recent years, their use in Scotland at the time of this study was very limited and was mainly confined to open surgical procedures. This may explain the comparable adhesion-related readmission rates associated with the yearly cohorts. Such findings indicate that gynaecological laparoscopy and laparotomy continue to exert a considerable impact on healthcare resources in terms of an adhesion-related burden, and that this burden is unlikely to decline. A cost-effectiveness model based on lower abdominal surgery cohorts from the SCAR database predicted that the cumulative year-on-year direct costs of adhesion-related readmissions for a 10-year period would be more than £569 million ( Wilson et al. , 2002 ). While similar data are, as yet, unavailable concerning gynaecological surgery, these calculations suggest that the economic costs resulting from adhesions associated with gynaecological procedures are likely to be considerable. Analyses of a similar model relating to gynaecological procedures are planned to address the issue of cost-effective interventions.

A range of strategies is available to minimize the risk of adhesion formation, including gentle tissue handling, meticulous haemostasis, minimally invasive surgery, constant irrigation and minimal foreign body contact ( Holmdahl et al. , 1997 ; Ling et al. , 2002 ). However, data from the present study indicate that such strategies have had little impact to date. For women undergoing gynaecological surgery, and particularly those undergoing tubal and ovarian surgery procedures, who wish to conceive, the implementation of good surgical practice, together with the widespread adoption of adhesion-reduction agents, may help to reduce readmission rates and minimize the risk of complications such as bowel obstruction, secondary infertility and chronic pain. Through such methods, it is to be hoped that we may reduce the burden of adhesive disease for both patients and health-care providers.

Figure 1.

Cumulative rates of directly or possibly adhesion-related hospital readmission episodes over 4 years in patients who underwent gynaecological laparoscopies in Scotland in 1996–1997. Readmission rates are calculated as percentages of the total number of initial surgical procedures and are presented according to the level of risk of adhesion formation (high, medium or low). Patients who underwent previous surgery are included.

Figure 1.

Cumulative rates of directly or possibly adhesion-related hospital readmission episodes over 4 years in patients who underwent gynaecological laparoscopies in Scotland in 1996–1997. Readmission rates are calculated as percentages of the total number of initial surgical procedures and are presented according to the level of risk of adhesion formation (high, medium or low). Patients who underwent previous surgery are included.

Figure 2.

Cumulative rates of directly or possibly adhesion-related hospital readmission episodes over 4 years in patients who underwent gynaecological laparotomies in Scotland in 1996–1997. Readmission rates are calculated as percentages of the total number of initial surgical procedures and are categorized by surgical site (Fallopian tubes, ovaries, uterus, vagina). Patients who underwent previous surgery are included.

Figure 2.

Cumulative rates of directly or possibly adhesion-related hospital readmission episodes over 4 years in patients who underwent gynaecological laparotomies in Scotland in 1996–1997. Readmission rates are calculated as percentages of the total number of initial surgical procedures and are categorized by surgical site (Fallopian tubes, ovaries, uterus, vagina). Patients who underwent previous surgery are included.

Figure 3.

Time to first directly or possibly adhesion-related hospital readmission in patients who underwent open or high-risk laparoscopic gynaecological surgery in Scotland in 1996–1997, 1997–1998 or 1998–1999. High-risk laparoscopic procedures are classified as those associated with a high risk of subsequent adhesion formation. Adhesion-related readmissions in patients in all yearly cohorts were monitored over 2 years.

Figure 3.

Time to first directly or possibly adhesion-related hospital readmission in patients who underwent open or high-risk laparoscopic gynaecological surgery in Scotland in 1996–1997, 1997–1998 or 1998–1999. High-risk laparoscopic procedures are classified as those associated with a high risk of subsequent adhesion formation. Adhesion-related readmissions in patients in all yearly cohorts were monitored over 2 years.

Table I.

OPCS4 codes and definitions for the most common surgical procedures performed in patients undergoing initial laparoscopic gynaecological surgery in 1996–1997 ( n =15 197)

Risk level a Code Procedure No. of patients Percentage of total no. of initial patients 
High Q493 Endoscopic drainage of cyst of ovary 263 37.3 
 Q423 Endoscopic division of adhesions of peritoneum 184 26.1 
 Q491 Endoscopic extirpation of lesion of ovary 53 7.52 
 Other  205 29.1 
Total   705 100 
Medium T439  Unspecified diagnostic endoscopic examination of peritoneum b 5529 99.25 
 T341 Diagnostic endoscopic examination of peritoneum and biopsy of lesion of peritoneum 15 0.27 
 T432 Diagnostic endoscopic examination of peritoneum and biopsy of lesion of intra-abdominal organ not elsewhere classified 0.04 
 Other  25 0.45 
Total   5571 100 
Low Q352 Endoscopic bilateral clipping of Fallopian tubes 5492 61.56 
 Q353 Endoscopic bilateral ringing of Fallopian tubes 1041 11.67 
 Q359 Unspecified endoscopic bilateral occlusion of Fallopian tubes 968 10.85 
 Other  1420 15.9 
Total   8921 100 
Risk level a Code Procedure No. of patients Percentage of total no. of initial patients 
High Q493 Endoscopic drainage of cyst of ovary 263 37.3 
 Q423 Endoscopic division of adhesions of peritoneum 184 26.1 
 Q491 Endoscopic extirpation of lesion of ovary 53 7.52 
 Other  205 29.1 
Total   705 100 
Medium T439  Unspecified diagnostic endoscopic examination of peritoneum b 5529 99.25 
 T341 Diagnostic endoscopic examination of peritoneum and biopsy of lesion of peritoneum 15 0.27 
 T432 Diagnostic endoscopic examination of peritoneum and biopsy of lesion of intra-abdominal organ not elsewhere classified 0.04 
 Other  25 0.45 
Total   5571 100 
Low Q352 Endoscopic bilateral clipping of Fallopian tubes 5492 61.56 
 Q353 Endoscopic bilateral ringing of Fallopian tubes 1041 11.67 
 Q359 Unspecified endoscopic bilateral occlusion of Fallopian tubes 968 10.85 
 Other  1420 15.9 
Total   8921 100 

Laparoscopic procedures were categorized according to level of risk (high, medium or low) of subsequent adhesion formation. Data are provided in terms of the number of patients undergoing each procedure and as a percentage of the total number of initial patients.

a

Since OPCS4 codes for the classification of laparoscopic procedures are less specific than those describing open surgery, initial laparoscopic procedures were classified according to the associated level of risk of adhesion formation (high-, medium- or low-risk) by a panel of experts. Selections were made in duplicate and then adjudicated to ensure accuracy. The high- and low-risk groups included specific therapeutic procedures, while the medium-risk group encompassed all other interventions, including therapeutic and interventional diagnostic laparoscopies.

b

Includes gynaecological laparoscopy, laparoscopy (unspecified) and peritoneoscopy not elsewhere classified.

Table II.

Numbers and percentages of patients requiring hospital readmission for events directly or possibly related to adhesions within the first year following laparoscopic gynaecological surgery in 1996–1997

 Code Description  Number of readmissions 1 year after surgery (%)
 
  
   High risk Medium risk Low risk 
Directly related      
Operative T413 Freeing of adhesions of peritoneum 6 (75.0) 46 (59.0) 9 (50.0) 
 Q341 Open freeing of adhesions of Fallopian tube 1 (12.5) 12 (15.4) 3 (16.7) 
 T428 Endoscopic division of adhesions of peritoneum 1 (12.5) 4 (5.1) – 
 Other  0 (0) 16 (20.5) 6 (33.3) 
Total   8 78 18 
Non-operative N994 Postprocedural pelvic peritoneal adhesions 1 (100) – – 
 K660 Peritoneal adhesions – 2 (100) 1 (100) 
 K565 Intestinal adhesions (bands) with obstruction    
 Other  0 (0) 0 (0) 0 (0) 
Total   1 2 1 
Possibly related      
Operative T439 Unspecified diagnostic endoscopic examination of peritoneum 17 (53.1) 79 (35.4) 28 (33.7) 
 T309 Unspecified opening of abdomen 4 (12.5) 17 (7.6) 10 (12.1) 
 Q221 Bilateral salpingo-ophorectomy 3 (9.4) 29 (13.0) 6 (7.2) 
 Other  8 (25) 98 (43.9) 39 (46.9) 
Total   32 223 83 
Non-operative R104 Other and unspecified abdominal pain 18 (50.0) 89 (46.6) 57 (46.3) 
 R103 Pain localized to other parts of lower abdomen 8 (22.2) 45 (23.6) 21 (17.1) 
 R102 Pelvic and perineal pain 6 (16.7) 25 (13.1) 17 (13.8) 
 Other  4 (11.2) 32 (16.8) 28 (22.8) 
Total   36 191 123 
 Code Description  Number of readmissions 1 year after surgery (%)
 
  
   High risk Medium risk Low risk 
Directly related      
Operative T413 Freeing of adhesions of peritoneum 6 (75.0) 46 (59.0) 9 (50.0) 
 Q341 Open freeing of adhesions of Fallopian tube 1 (12.5) 12 (15.4) 3 (16.7) 
 T428 Endoscopic division of adhesions of peritoneum 1 (12.5) 4 (5.1) – 
 Other  0 (0) 16 (20.5) 6 (33.3) 
Total   8 78 18 
Non-operative N994 Postprocedural pelvic peritoneal adhesions 1 (100) – – 
 K660 Peritoneal adhesions – 2 (100) 1 (100) 
 K565 Intestinal adhesions (bands) with obstruction    
 Other  0 (0) 0 (0) 0 (0) 
Total   1 2 1 
Possibly related      
Operative T439 Unspecified diagnostic endoscopic examination of peritoneum 17 (53.1) 79 (35.4) 28 (33.7) 
 T309 Unspecified opening of abdomen 4 (12.5) 17 (7.6) 10 (12.1) 
 Q221 Bilateral salpingo-ophorectomy 3 (9.4) 29 (13.0) 6 (7.2) 
 Other  8 (25) 98 (43.9) 39 (46.9) 
Total   32 223 83 
Non-operative R104 Other and unspecified abdominal pain 18 (50.0) 89 (46.6) 57 (46.3) 
 R103 Pain localized to other parts of lower abdomen 8 (22.2) 45 (23.6) 21 (17.1) 
 R102 Pelvic and perineal pain 6 (16.7) 25 (13.1) 17 (13.8) 
 Other  4 (11.2) 32 (16.8) 28 (22.8) 
Total   36 191 123 

Data are presented in terms of operative and non-operative causes of readmission and are categorized according to the type of procedure performed using OPCS4 and ICD10 surgical and diagnostic codes. Data are provided for the three procedures performed most commonly within each category.

Table III.

Numbers and percentages of patients requiring hospital readmission for events directly or possibly related to adhesions within the first year following gynaecological laparotomies in 1996–1997

 Code Description Number of readmissions one year after surgery (%)    
   Fallopian tubes Ovaries Uterus Vagina 
Directly related       
Operative T413 Freeing of adhesions of peritoneum 2 (50) 2 (66) 16 (64) 0 (0) 
  T439 a Unspecified diagnostic endoscopic examination of peritoneum 0 (0) 0 (0) 7 (28) 0 (0) 
 T423 Endoscopic division of adhesions of peritoneum 1 (25) 0 (0) 2 (8) 0 (0) 
 Q341 Open freeing of adhesions of Fallopian tubes 1 (25) 0 (0) 0 (0) 0 (0) 
 T361 Omentectomy 0 (0) 1 (33) 0 (0) 0 (0) 
 Other  0 (0) 0 (0) 0 (0) 0 (0) 
Total   4 3 25 0 
Non-operative K565 Intestinal adhesions (bands) with obstruction 0 (0) 1 (50) 3 (43) 0 (0) 
 K660 Peritoneal adhesions 0 (0) 1 (50) 3 (43) 0 (0) 
 N998 Other postprocedural disorders of genitourinary system 0 (0) 0 (0) 1 (14) 0 (0) 
 Other  0 (0) 0 (0) 0 (0) 0 (0) 
Total   0 2 7 0 
Possibly related       
Operative T439 Unspecified diagnostic endoscopic examination of peritoneum 8 (29) 5 (38) 25 (26) 
 Q074 Total abdominal hysterectomy, not elsewhere classified – – 25 (26) 
 T309 Unspecified opening of abdomen – – 10 (10) 
 Q413 Dye test of Fallopian tubes 6 (21) – – 
 Q233 Unilateral salpingectomy not elsewhere classified 5 (18) – – 
 Other  9 (32) 8 (62) 38 (38) 
Total   28 13 98 0 
Non-operative R104 Other and unspecified abdominal pain 10 (37) 16 (59) 106 (50) 0 (0) 
 R103 Pain localized to other parts of lower abdomen 6 (22) 2 (8) 35 (16) 0 (0) 
 K566 Other and unspecified intestinal obstruction – – 23 (11) 0 (0) 
 R102 Pelvic and perineal pain 3 (11) – – 0 (0) 
 R11X Nausea and vomiting – 3 (11) – 0 (0) 
 Other  8 (30) 6 (22) 49 (23) 0 (0) 
Total   27 27 213 0 
 Code Description Number of readmissions one year after surgery (%)    
   Fallopian tubes Ovaries Uterus Vagina 
Directly related       
Operative T413 Freeing of adhesions of peritoneum 2 (50) 2 (66) 16 (64) 0 (0) 
  T439 a Unspecified diagnostic endoscopic examination of peritoneum 0 (0) 0 (0) 7 (28) 0 (0) 
 T423 Endoscopic division of adhesions of peritoneum 1 (25) 0 (0) 2 (8) 0 (0) 
 Q341 Open freeing of adhesions of Fallopian tubes 1 (25) 0 (0) 0 (0) 0 (0) 
 T361 Omentectomy 0 (0) 1 (33) 0 (0) 0 (0) 
 Other  0 (0) 0 (0) 0 (0) 0 (0) 
Total   4 3 25 0 
Non-operative K565 Intestinal adhesions (bands) with obstruction 0 (0) 1 (50) 3 (43) 0 (0) 
 K660 Peritoneal adhesions 0 (0) 1 (50) 3 (43) 0 (0) 
 N998 Other postprocedural disorders of genitourinary system 0 (0) 0 (0) 1 (14) 0 (0) 
 Other  0 (0) 0 (0) 0 (0) 0 (0) 
Total   0 2 7 0 
Possibly related       
Operative T439 Unspecified diagnostic endoscopic examination of peritoneum 8 (29) 5 (38) 25 (26) 
 Q074 Total abdominal hysterectomy, not elsewhere classified – – 25 (26) 
 T309 Unspecified opening of abdomen – – 10 (10) 
 Q413 Dye test of Fallopian tubes 6 (21) – – 
 Q233 Unilateral salpingectomy not elsewhere classified 5 (18) – – 
 Other  9 (32) 8 (62) 38 (38) 
Total   28 13 98 0 
Non-operative R104 Other and unspecified abdominal pain 10 (37) 16 (59) 106 (50) 0 (0) 
 R103 Pain localized to other parts of lower abdomen 6 (22) 2 (8) 35 (16) 0 (0) 
 K566 Other and unspecified intestinal obstruction – – 23 (11) 0 (0) 
 R102 Pelvic and perineal pain 3 (11) – – 0 (0) 
 R11X Nausea and vomiting – 3 (11) – 0 (0) 
 Other  8 (30) 6 (22) 49 (23) 0 (0) 
Total   27 27 213 0 

Data are presented in terms of operative and non-operative causes of readmission and are categorized according to the type of procedure performed using OPCS4 and ICD10 surgical and diagnostic codes. Data are provided for the three procedures performed most commonly within each surgical site category.

a

Code defined as a directly adhesion-related cause of readmission when associated with a directly related non-operative admission (e.g. K565, K660, N998).

Table IV.

Cumulative numbers and rates of directly or possibly adhesion-related hospital readmission episodes over 4 years in patients who underwent open ( n =8849) or laparoscopic ( n =15 197) gynaecological surgery in Scotland in 1996–1997

Surgery type Initial no. of patients (%)  Cumulative no. and (rate) a of directly or possibly adhesion-related readmission episodes in the years following initial surgery
 
   
  Year 1 Year 2 Year 3 Year 4 
Directly related      
Laparoscopy      
High risk 705 (4) 9 (1.3) 14 (2.0) 17 (2.4) 21 (3.0) 
Medium risk 5571 (37) 84 (1.5) 118 (2.1) 137 (2.5) 154 (2.8) 
Low risk 8921 (59) 19 (0.2) 35 (0.4) 48 (0.5) 56 (0.6) 
Total 15 197 (100) 112 (0.7) 167 (1.1) 202 (1.3) 231 (1.5) 
Laparotomy      
Fallopian tubes 466 (5) 4 (0.9) 7 (1.5) 11 (2.4) 15 (3.2) 
Ovaries 328 (3.7) 7 (2.1) 13 (4.0) 18 (5.5) 23 (7.0) 
Uterus 8024 (91) 48 (0.6) 69 (0.9) 104 (1.3) 139 (1.7) 
Vagina 31 (0.3) 0 (0.0) 0 (0.0) 3 (9.7) 3 (9.7) 
Total 8849 (100) 59 (0.7) 89 (1.0) 136 (1.5) 180 (2.0) 
Possibly related      
Laparoscopy      
High risk 705 (4) 101 (14.3) 146 (20.7) 186 (26.4) 233 (33.0) 
Medium risk 5571 (37) 502 (9.0) 804 (14.4) 1066 (19.1) 1337 (24.0) 
Low risk 8921 (59) 248 (2.8) 491 (5.5) 695 (7.8) 874 (9.8) 
Total 15197 (100) 851 (5.6) 1441 (9.5) 1947 (12.8) 2444 (16.1) 
Laparotomy      
Fallopian tubes 466 (5) 68 (14.6) 111 (23.8) 144 (30.9) 163 (35.0) 
Ovaries 328 (3.7) 52 (15.9) 81 (24.7) 115 (35.1) 143 (43.6) 
Uterus 8024 (91) 394 (4.9) 647 (8.1) 824 (10.3) 976 (12.2) 
Vagina 31 (0.3) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 
Total 8849 (100) 514 (5.8) 839 (9.5) 1083 (12.2) 1282 (14.5) 
Surgery type Initial no. of patients (%)  Cumulative no. and (rate) a of directly or possibly adhesion-related readmission episodes in the years following initial surgery
 
   
  Year 1 Year 2 Year 3 Year 4 
Directly related      
Laparoscopy      
High risk 705 (4) 9 (1.3) 14 (2.0) 17 (2.4) 21 (3.0) 
Medium risk 5571 (37) 84 (1.5) 118 (2.1) 137 (2.5) 154 (2.8) 
Low risk 8921 (59) 19 (0.2) 35 (0.4) 48 (0.5) 56 (0.6) 
Total 15 197 (100) 112 (0.7) 167 (1.1) 202 (1.3) 231 (1.5) 
Laparotomy      
Fallopian tubes 466 (5) 4 (0.9) 7 (1.5) 11 (2.4) 15 (3.2) 
Ovaries 328 (3.7) 7 (2.1) 13 (4.0) 18 (5.5) 23 (7.0) 
Uterus 8024 (91) 48 (0.6) 69 (0.9) 104 (1.3) 139 (1.7) 
Vagina 31 (0.3) 0 (0.0) 0 (0.0) 3 (9.7) 3 (9.7) 
Total 8849 (100) 59 (0.7) 89 (1.0) 136 (1.5) 180 (2.0) 
Possibly related      
Laparoscopy      
High risk 705 (4) 101 (14.3) 146 (20.7) 186 (26.4) 233 (33.0) 
Medium risk 5571 (37) 502 (9.0) 804 (14.4) 1066 (19.1) 1337 (24.0) 
Low risk 8921 (59) 248 (2.8) 491 (5.5) 695 (7.8) 874 (9.8) 
Total 15197 (100) 851 (5.6) 1441 (9.5) 1947 (12.8) 2444 (16.1) 
Laparotomy      
Fallopian tubes 466 (5) 68 (14.6) 111 (23.8) 144 (30.9) 163 (35.0) 
Ovaries 328 (3.7) 52 (15.9) 81 (24.7) 115 (35.1) 143 (43.6) 
Uterus 8024 (91) 394 (4.9) 647 (8.1) 824 (10.3) 976 (12.2) 
Vagina 31 (0.3) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 
Total 8849 (100) 514 (5.8) 839 (9.5) 1083 (12.2) 1282 (14.5) 

Readmissions are classified as directly or possibly related to adhesions and are presented in terms of laparoscopy (high-, medium- or low-risk procedures) and laparotomy (procedures performed on the Fallopian tubes, ovaries, uterus or vagina).

a

Rate = number of readmission episodes per 100 initial patients.

Table V.

Cumulative numbers and rates of directly or possibly adhesion-related hospital readmission episodes over 4 years in patients who underwent open ( n =8849) or laparoscopic ( n =15 197) gynaecological surgery in Scotland in 1996–1997

Surgery type Initial no. of patients (%)  Cumulative no. and (rate) a of directly or possibly adhesion-related readmission episodes in the years following initial surgery, excluding surgery within the previous 5 years
 
   
  Year 1 Year 2 Year 3 Year 4 
Directly related      
Laparoscopy      
High risk 359 (3) 2 (0.6) 3 (0.8) 3 (0.8) 4 (1.1) 
Medium risk 3829 (35) 47 (1.2) 69 (1.8) 80 (2.1) 93 (2.4) 
Low risk 6791 (62) 12 (0.2) 22 (0.3) 27 (0.4) 31 (0.5) 
Total 10979 (100) 61 (0.6) 94 (0.9) 110 (1.0) 128 (1.2) 
Laparotomy      
Fallopian tubes 229 (4.5) 3 (1.3) 4 (1.7) 6 (2.6) 8 (3.5) 
Ovaries 226 (4.3) 1 (0.4) 4 (1.8) 5 (2.2) 7 (3.1) 
Uterus 4481 (91) 13 (0.3) 22 (0.5) 36 (0.8) 47 (1.0) 
Vagina 9 (0.2) 0 (0.0) 0 (0.0) 3 (33.3) 3 (33.3) 
Total 4945 (100) 17 (0.3) 30 (0.6) 47 (1.0) 62 (1.3) 
Possibly related      
Laparoscopy      
High risk 359 (3) 46 (12.8) 68 (18.9) 85 (23.7) 110 (30.6) 
Medium risk 3829 (35) 273 (7.1) 438 (11.4) 584 (15.3) 750 (19.6) 
Low risk 6791 (62) 149 (2.2) 303 (4.5) 427 (6.3) 539 (7.9) 
Total 10979 (100) 468 (4.3) 809 (7.4) 1096 (10.0) 1399 (12.7) 
Laparotomy      
Fallopian tubes 229 (4.5) 28 (12.2) 46 (20.1) 57 (24.9) 63 (27.5) 
Ovaries 226 (4.3) 29 (12.8) 39 (17.3) 53 (23.5) 68 (30.1) 
Uterus 4481 (91) 178 (4.0) 287 (6.4) 369 (8.2) 438 (9.8) 
Vagina 9 (0.2) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 
Total 4945 (100) 235 (4.8) 372 (7.5) 479 (9.7) 569 (11.5) 
Surgery type Initial no. of patients (%)  Cumulative no. and (rate) a of directly or possibly adhesion-related readmission episodes in the years following initial surgery, excluding surgery within the previous 5 years
 
   
  Year 1 Year 2 Year 3 Year 4 
Directly related      
Laparoscopy      
High risk 359 (3) 2 (0.6) 3 (0.8) 3 (0.8) 4 (1.1) 
Medium risk 3829 (35) 47 (1.2) 69 (1.8) 80 (2.1) 93 (2.4) 
Low risk 6791 (62) 12 (0.2) 22 (0.3) 27 (0.4) 31 (0.5) 
Total 10979 (100) 61 (0.6) 94 (0.9) 110 (1.0) 128 (1.2) 
Laparotomy      
Fallopian tubes 229 (4.5) 3 (1.3) 4 (1.7) 6 (2.6) 8 (3.5) 
Ovaries 226 (4.3) 1 (0.4) 4 (1.8) 5 (2.2) 7 (3.1) 
Uterus 4481 (91) 13 (0.3) 22 (0.5) 36 (0.8) 47 (1.0) 
Vagina 9 (0.2) 0 (0.0) 0 (0.0) 3 (33.3) 3 (33.3) 
Total 4945 (100) 17 (0.3) 30 (0.6) 47 (1.0) 62 (1.3) 
Possibly related      
Laparoscopy      
High risk 359 (3) 46 (12.8) 68 (18.9) 85 (23.7) 110 (30.6) 
Medium risk 3829 (35) 273 (7.1) 438 (11.4) 584 (15.3) 750 (19.6) 
Low risk 6791 (62) 149 (2.2) 303 (4.5) 427 (6.3) 539 (7.9) 
Total 10979 (100) 468 (4.3) 809 (7.4) 1096 (10.0) 1399 (12.7) 
Laparotomy      
Fallopian tubes 229 (4.5) 28 (12.2) 46 (20.1) 57 (24.9) 63 (27.5) 
Ovaries 226 (4.3) 29 (12.8) 39 (17.3) 53 (23.5) 68 (30.1) 
Uterus 4481 (91) 178 (4.0) 287 (6.4) 369 (8.2) 438 (9.8) 
Vagina 9 (0.2) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 
Total 4945 (100) 235 (4.8) 372 (7.5) 479 (9.7) 569 (11.5) 

Readmissions are classified as directly or possibly related to adhesions and are presented in terms of laparoscopy (high-, medium- or low-risk procedures) and laparotomy (procedures performed on the Fallopian tubes, ovaries, uterus or vagina). Patients who underwent abdominopelvic surgery within the previous 5 years are excluded.

a

Rate = number of readmission episodes per 100 initial patients.

The SCAR steering group conceived the idea of establishing the gynaecological laparoscopic burden of adhesions and comparing it with the burden associated with gynaecological laparotomy. A.D.K. and A.M.C. coordinated the categorization of surgical and disease codes and the planning of data extraction. A.M.L. and R.J.S.H. selected the codes. D.C. extracted data from the patient-linked Medical Record Linkage database, assisted by A.R.F. and J.H.B. All authors interpreted the data, commented on the first draft and approved the final version. This study was supported by Shire Pharmaceuticals. A.M.L. has been involved in adhesions research for over 10 years. During this time he has been in receipt of research funding from Ethicon, Gynecare, Genzyme and Shire Pharmaceuticals. He has received honoraria from Ethicon, Gynecare, Genzyme, Shire Pharmaceuticals, Confluent Surgical Inc, and ML Laboratories for attendance at meetings and participation in workshops on studies and adhesion-prevention products. R.J.S.H. has been involved in adhesions research for over 10 years and has received honoraria from Genzyme, Shire Pharmaceuticals and ML Laboratories for attendance at meetings and participation in workshops on studies and adhesion-prevention products. D.C., J.H.B. and A.R.F. have no competing interests. I.S.D. received funding for data extraction and analysis of the Medical Record Linkage database. A.M.C. and A.D.K. have been involved in adhesions research for over 8 years and have received consultancy funding from Genzyme, ML Laboratories and Shire Pharmaceuticals. Their time in coordinating the research project and undertaking analyses was funded by Shire Pharmaceuticals.

Fellow SCAR advisers: Professor Harold Ellis, Guy's, King's and St Thomas' School of Biomedical Sciences, King's College, London; Malcolm Wilson, Christie Hospital, Manchester; Donald Menzies, Colchester Hospital, Colchester; Michael Parker, Darent Valley Hospital, Dartford; Graham Sunderland, Southern General Hospital, Glasgow; Jeremy Thompson, Chelsea and Westminster Hospital, London; Brendan Moran, North Hampshire Hospital, Basingstoke; Professor Ian Ford, Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK.

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Author notes

1Isis Fertility Centre, Colchester CO4 9YA, 2Southern General NHS Trust, Glasgow G51 4TF, 3Information and Statistics Division, Common Services Agency, Trinity Park House, Edinburgh EH5 3SQ 4Evicom, Twickenham TW1 2AA, and 5Corvus, Buxted TN22 4PB, UK