The ANZ hernia repair practices study: low consensus on inguinal and small ventral hernia management and infrequent long-term follow-up.

Abstract

There are some concerns among professional bodies and health insurers that variations in groin hernia repair approaches in Australia and New Zealand (ANZ) may be contributing to low-value surgical care.1 In Australia alone, Medicare spent $7.9 million on groin hernia repairs in 2021, and 61% of this expenditure was for minimally invasive surgery approaches.2 There is ongoing debate about whether an open, laparoscopic (or robotic) approach for primary or recurrent groin hernias is best,3 and international data are often hard to interpret and difficult to implement into local practice.4 Hernia treatment choices in ANZ are largely driven by a surgeon's level of knowledge, experience, and preferences. The ANZ Hernia Repair Practices Study (ANZ HRPS) collected over 200 anonymous reports about inguinal and ventral hernia repair approaches from a representative sample of surgeon and trainee members of General Surgeons Australia (GSA) and the New Zealand Association of General Surgeons (NZAGS). It is the first comprehensive bi-national study of hernia surgery practices including the choice of repair technique, mesh and fixation materials, surgeon attitudes towards same-day surgery, the impact of COVID-19 restrictions,5 and the timing of postoperative follow-up consultations. This is the first of a series of articles reporting findings for the management of inguinal and small (<2 cm) ventral hernias. A cross-sectional anonymous survey of members of the GSA (n = 1580) and the NZAGS (n = 224) was conducted in July 2021. The survey hyperlink was distributed via an email invitation letter (endorsed by the senior author) and an information sheet describing the study objectives and contact information. All respondents indicated their consent by submitting the survey. The survey development process is provided in Appendix A. Data were collected and managed using REDCap hosted at The University of Sydney.6, 7 Approval for this study was provided by The University of Sydney Human Research Ethics Committee (2020/748). Respondents completed multiple choice and 4- or 5-point Likert-scale questions on whether and how often they disagreed or agreed with statements. Optional free-text boxes were also provided. The questionnaire is available from the authors on request. Descriptive analysis was performed using IBM SPSS Statistics for Macintosh, Version 28.0 (Armonk, NY: IBM Corp). A total of 244 respondents returned the survey (14% response rate). Data from those who discontinued the survey (n = 14) and one with outlying responses were excluded. The final sample included 229 pre- and post-fellowship surgeons (mean ± SD, standard deviation 13 ± 13 years post-fellowship) from Australia (93%; 214/229) and New Zealand (7%; 15/229). Most respondents operated in both the private and public sectors (62%, 142/229), and most in urban settings only (76%, 175/229). Over a third of respondents (37%; 66/229) stated that they did not perform any hernia surgery as the primary operator at all, and so presumably their opinions were based on either prior experience or their observations of others in practice (Table 1). Totally extraperitoneal (TEP) repair was the most preferred technique for both primary unilateral (47%; 107/229) and primary bilateral inguinal hernias (61%; 139/229). Most respondents stated that they performed an anterior ‘open’ repair for recurrent hernias after a previous TEP (69%; 159/229) or transabdominal preperitoneal (TAPP) repair (67%; 154/229). By contrast, they preferred a posterior ‘minimally invasive’ approach after a previous open repair (TEP: 60%; 138/229 versus TAPP: 8%; 19/229). One in ten (11%; 26/229) of the surgeons surveyed used an open approach after a failed open repair, and three-quarters (74%; 170/229) used an MIS approach after a failed MIS repair. Two-thirds (66%; 150/229) of the surgeons chose a monolayer synthetic mesh (e.g., polypropylene, polyester) for the repair of an inguinal hernia, 16% (36/229) used a composite mesh (e.g., ProGrip™ (Medtronic, Dublin, Ireland)), 7% (15/229) did not use mesh, 2% (4/229) used a biosynthetic mesh, and none implanted a biological mesh (Fig. 2a). Absorbable and non-absorbable sutures or tacks were top choices for mesh fixation among the surgeons (33%; 76/229 vs. 31%; 71/229). One in five (21%; 47/229) used self-fixing mesh, 15% (34/229) used tissue glue, and 5% (11/229) did not fix the mesh (Fig. 2b). Most respondents (89%; 158/178) believed that patients with ‘non-complicated’ inguinal or small (<2 cm) ventral or incisional hernias can be managed safely and effectively as same-day repairs (i.e., not an overnight stay). However, less than a third (28%; 49/177) of surgeons routinely performed these types of operations as ambulatory procedures. Each of the issues related to same-day repair for non-complicated hernias was ranked in order of importance to the respondent with 1 being the value of most importance and 6 of least (Fig. 1). Overall, respondents rated ‘an appropriate day surgery facility’ as the most important issue and ‘hospital-insurer arrangements’ as the least important issue. Patient preference was ranked as a more important issue than either the surgeon's own preference or knowledge of evidence-based practice (Table 2). A quarter (24%; 36/150) of respondents indicated that 25 or more operations were postponed by 3 months due to COVID-19 restrictions on elective surgery,5 with those who worked in public hospitals only most affected. Almost three-quarters (73%; 129/178) of respondents indicated that their rates of same-day repair remained ‘about the same’ due to COVID-19 restrictions and only 19% (34/178) were ‘more likely’ to adopt this approach in the future. Forty-six percent (79/172) of respondents stated that they scheduled the first postoperative review within 3 weeks post-discharge, and the remainder did so within 3 months. Respondents stated that they rarely followed-up their patients at or past 12 months after the hernia operation – only 3% (5/172) stated that they did this routinely. Surprisingly, 10 % (17/172) of the surgeons surveyed stated that they only conducted a postoperative examination ‘at the patient's request’. (Fig. 3). The ANZ HPRS found an increasing trend in the use of minimally invasive approaches for inguinal hernia repair (mainly TEP) among ANZ surgeons and trainees, consistent with Australian2, 8, 9 and international population-based studies10 showing preferences for laparoscopic over open repair techniques since 2000. There was consensus on the use of monolayer synthetic mesh to reinforce the hernia defect, but the surgeons in this study selected a range of mesh fixation methods. The timing and frequency of postoperative follow-up time frames varied greatly, with most surgeons scheduling a single clinic visit within 3 months after an inguinal hernia repair procedure. Concerningly, less than a third of respondents indicated that they had procedural volumes of >25 cases per year. This is interesting given that minimally invasive surgery (MIS) for inguinal hernia repair (TEP, TAPP or robotic) are technically demanding procedures that may be associated with a steeper learning curve than open repairs. The concept that a surgeons' laparoscopic caseload is associated with rates of recurrence was first proposed following a multi-institutional randomized controlled trial of open and laparoscopic inguinal hernia repair. The study, published in the New England Journal of Medicine in 2004, showed that surgeons who self-reported >250 procedures had significantly lower recurrence rates than those who performed 0–250 procedures (>10% versus <5%, P < 0.001).11 Whilst subsequent studies support a relatively low learning curve to achieve competency in open Lichtenstein procedures (possibly as low as 40 cases),12, 13 other studies have shown that the caseload required to reach proficiency in MIS repairs has been overestimated—and may be closer to 60 cases only.14, 15 Notwithstanding the small increased risk of visceral, vascular or nerve injury in MIS inguinal hernia repairs compared with open approaches, these shorter learning curves likely reflect a general improvement in ‘MIS competency’ among the surgical community. Another key finding is that whilst most of the surgeons typically used monolayer synthetic mesh to reinforce the hernia defect, they used an assortment of fixation materials and techniques to secure the mesh. Although it is unclear whether this variation has a negative impact on patient outcomes, it is consistent with the literature showing no clear clinical benefit among mesh fixation methods.16 In relation to the few surgeons who opted to use biosynthetic meshes, the higher cost incurred for a non-complicated inguinal hernia repair seems difficult to justify.17 There was a consensus among the respondents that same-day surgery for non-complicated hernias was safe and effective, yet overnight stays are standard practice for most Australasian surgeons. The ranking data show that patient preference may have a greater influence on the surgeons' perioperative decisions for same-day hernia management than their own knowledge or experience. Moreover, the surgeons rated healthcare expenditure (patient out-of-pocket costs, hospital-insurer arrangements) among the least important issues. These data show that any attempt at achieving the >70% target for same-day surgery set by the RACS,18 thereby reducing the negative impact of unwarranted practice variations, is likely to require increasing public awareness of the benefits of same-day surgery as well as introducing financial incentives.18-20 In this study, the surgeons surveyed markedly differed in the timing and frequency of routine follow-up care, and very few tracked their long-term patient outcomes or complication rates. Specifically, many of the surgeons rarely examined patients beyond 3 months of the operation—a period when late complications including chronic pain and recurrence tend to emerge.4 The absence of longer-term follow-up 12 months after an inguinal hernia repair, encompassing a wide variety of operative techniques and novel mesh technology, suggests that patient quality of life outcomes in ANZ are largely unknown. These surgeon-dependent practices for common elective procedures may not only be unsustainable in the long term, but also seem out of place in an era centred on delivering evidence-informed surgical care and measuring patient-reported outcomes. The study findings may be affected by non-response bias due to the small sample size and modest response rate, despite the survey link being distributed to all GSA and NZAGS members. In 2020, two hernia-related surveys of ‘active’ post-Fellowship members of the GSA were published in the ANZ Journal of Surgery and returned rates of 10% (82/826)21 to 25% (198/785).22 The response rate for the current study falls in this range and rose to 22% (171/787) with subgroup analysis of post-Fellowship surgeons only, suggesting that the rate obtained was typical for the sample population. Another potential factor influencing the generalisability of the study findings is the inclusion of respondents who do not routinely perform hernia repairs as the primary operator. However, this group only comprised six respondents who were mostly trainees. Unexpectedly, COVID-19 restrictions did not affect the number of inguinal hernia repair operations postponed for >3 months. This is likely reflecting the larger share of elective cases performed in the private sector—where most the respondents operated. This report illustrates the need for standardized clinical pathways for inguinal hernia management to allow for safe and effective surgical care for this common elective procedure. The data show wide variations in practice and, notably, a poor translation of evidence-based surgery into clinical practice.20, 23 The formation of the ANZ Hernia Society in 2021 not only signals a shift in surgeon attitudes24 but will ideally support the NSW Agency for Clinical Innovation's push towards establishing high value-based surgical care.25 It is hoped that data from the ANZ HRPS will provide an empirical basis for adopting sustainable practices including long-term follow-up and normalizing same-day inguinal hernia repair. Open access publishing facilitated by The University of Sydney, as part of the Wiley - The University of Sydney agreement via the Council of Australian University Librarians. Joanna M. Z. Mills: Conceptualization; methodology; data curation; data analysis; writing. Georgina M. Luscombe: Conceptualization; methodology; supervision. Thomas J. Hugh: Funding; conceptualization; methodology; supervision; writing. The questionnaire was developed based on relevant literature review and feedback from experienced senior clinicians. A pilot study was administered to six participants and the items were revised to improve clarity. The questionnaire comprised of four sections: (1) non-identifiable demographic details and workplace information, (2) surgeon's experience and hernia repair approaches, (3) surgeon's experiences communicating with patients about hernia treatments, (4) surgeon's communication preferences with their patient's GP and perceptions about the GP's role in post-surgical care. Quantitative data from Section 1 and quantitative data relating to the management of inguinal and small (<2 cm) ventral hernias are herein reported.