Hernia repair is one of the long-lasting surgical procedures performed day by day, which can be traced back to the era of ancient Egypt . Recurrence following hernia repairs has improved enormously, thanks to the invention and wide adaption of tension-free mesh repair. For ventral/incisional hernias, recurrence rate could be reduced from 50% of primary repair to 10-23% with a prosthetic mesh . With the reduced rate of recurrence equal or less than 1% for groin hernia repair, more attention should be paid to complications which may bother patients’ long-term wellbeing such as chronic pain .
To understand treatment outcomes further, a valid tool to assess the multi-factorial quality of life should be sought by surgical communities. There are several quality of life instruments specific for hernia disease, such as Caroline Comfort Scale (CCS), HerQLes, EuraHSQoL, COMI-hernia, Inguinal Pain Questionnaire and Brief Pain Inventory (BPI), to name a few [17–22]. Our published HERQL targets both abdominal wall and inguinal hernia, traditional open and minimally invasive surgeries, and various mesh materials [10–11]. HERQL deciphers hernia-related multi-dimensional quality of life aspects, including symptomatic physical or psychological burden and functionalities. One merit of using HERQL for hernia outcomes research is the determination of the causal relationship between formative symptomatic scales and reflective functional indicators, which is elaborated through the pathway analysis of structural equation modeling (SEM) [23–25].
In current study, the experience of developing a mobile app to facilitate the long-term follow up of hernia patients was reported. The cloud-based system eliminated the need of returning hospital visits for subjects who had undergone hernia repairs as early as a decade ago, which in turn wound augment the follow up condition. Hernia is one of surgical diseases with compromised long-term follow-up as there is neither periodic surveillance nor medicine prescription once the defect is repaired. In addition, patients with recurrent disease may seek second opinions and reoperation from surgeons other than the one with failed repair. Therefore, an easy to assess reporting system will be of great value for patients to present their immediate abdominal or groin conditions and for surgeons to update treatment outcomes.
Under these hypotheses, we sent inviting mail to subjects who had their hernias repaired at our institute more than one year ago, with these cases identified from medical records. With enclosed preset ID and password, they could easily download the iOS or Android version of mobile app, complete quality of life survey and electrical signature within a few minutes. For those not familiar with mobile app, a Google Forms survey provided an on-line alternative. The response rate was 11.9%, or slightly more than one-tenth of identified candidates.
Taking the study conducted by Heniford et al. as an example, CCS questionnaire was mailed to 1,048 patients and their response rate was 12.9% . We invited hernia patients who completed surgery more than one year before the enrollment, and our response rate was like that of CCS study while a much longer time interval between hernioplasty and questionnaire survey was pronounced in current study. One major reason for low response rate was loss of contact due to wrong address resulting in undelivered mails. With longer follow up, migration occurred naturally while some subjects might have passed away, and these patients finally became unapproachable. Although compensation was arranged, lack of incentive, worry about fraud and reluctance to participate might compromise recovery of HERQL survey substantially, which constituted another reason for low response.
Despite the fair response rate of slightly more than one-tenth, successful HERQL assessment was performed for 311 patients with majority diagnosed with groin hernias, reflecting the clinical scenarios of hernia population. Our results suggested that most hernia patients enjoyed a relatively low recurrence rate (less than 1%), and around 90% of them reported a satisfactory/very satisfactory hernia repair experience. Only slightly more than 30% of surveyed subjects reported hernioplasty-related discomfort, and less than 40% experienced mesh foreign body sensation. Most importantly, 90.3% of hernia patients ascertained improvement in quality of life following hernia surgeries, indicating that elimination of hernia-related symptoms might be the main contributor of such improvement.
In our previous study, 192 mesh plug groin hernia repairs were compared with 234 PHS repairs. Postoperatively the mesh plug group had higher incidence of chronic non-disabling groin pain . In current study, subgroup analysis was conducted comparing prosthetic devices of plug and PHS/UHS. Corresponding to our previous study, mesh plug did hamper hernioplasty outcomes with worse symptoms and compromised functionality. Worse (higher) symptomatic scores were reported from analgesic usage, health impact, economic burden, foreign body sensation and discomfort severity as well as compromised functionalities in less satisfaction, confidence in hernia repair and quality of life improvement.
Conceptual structure of HERQL with and without of the auxiliary post-operative module displayed satisfactory model fit indices (Fig. 3), further augmenting the superiority of SEM approach of HERQL. Fayers et al. initiated the efforts to use SEM for conceptual structure of quality of life measuring instrument, who aimed to separate causal variables (symptoms) from effect indicators (functional domains) . The causal and indicator variables model proposed by Fayers et al. and Boehmer et al. formed the basis of HERQL structure [10–11, 24–25]. The critical rationale underpinning the causal-indicative duality was that hernia-associated symptoms impaired subjective quality of life perception, which was subsequently reflected in functional domain indicator variables, as well as in patients’ satisfaction from the postoperative module. Elaboration on causal/indicator duality recognized one-way causal effects of symptomatic scales upon functional domains, but not vice versa .
There were some limitations of the study. First, retrospective design inevitably brought recall bias, especially for those with longer follow up. Second, not all clinical and demographic data were available through chart reviews, such as body mass index and fascia defect size, which could hamper post hoc and multi-variate analysis considerably. Third, some elderly patients might not be able to complete the survey without an assistant, and there was no printed questionnaire if mobile app was not properly installed. Fourth, no further remind mail or phone call was attempted if there was no response from the initial inviting mail.
Experience learnt from the study can translate into further hernia outcomes research design. For example, to establish an updated Hernia Registry which includes a novel mobile app to enhance the follow up of hernia patients, and a cloud-based database for both surgeons and hernia patients. The corroborative database is suitable for surgeons to collect clinical and operative details from hernia surgeries and provides a platform for real-time communication between surgeons and hernia patients to enhance post-operative follow up and outcomes assessment. Surgeons could enter the clinical and operative data immediately after completion of hernia repairs with mobile devices while sensitive clinical data were secured and restricted to authorized personnel. On the other hand, hernia patients could review their clinical and operative details in a well-designed and self-explanatory manner. Hernia patients could also record the post-operative events, such as visual analog pain scale, wound condition and complications, as well as administer HERQL periodically, to assess the outcomes of hernia repair. Finally, the instant message communication subunit provides an easy and efficient way for patients reporting any discomfort to their surgeons and a proper response from the latter could enhance the long-term follow up compliance rate of hernia patients.