Mesh fixation techniques for laparoscopic inguinal hernia repair in adults
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To determine whether there is any difference in patient outcome and morbidity when the mesh is fixed or not during laparoscopic inguinal hernia repair.
To compare different methods of mesh fixation i.e.: no fixation, fibrin glue sealant, tacks, and sutures.
The primary outcomes measured will be pain (inguinal or testicular), numbness and hernia recurrence.
The secondary outcome measures will be length of surgery, length of hospital stay, urinary retention, recovery time for normal activity, infection of the mesh.
Background
Description of the condition
Inguinal hernia repair is the commonest general surgical operation and can be performed either laparoscopically or by the anterior/open approach. Laparoscopic repair is associated with less post‐operative pain and a more speedy return to normal activities of daily life (McCormack 2003). Many laparoscopic inguinal hernia repairs are now performed as day case procedures and, as such, patients perceive the surgery as minor and do not accept significant morbidity. Post‐operative pain following inguinal hernia repair (of either approach) is a significant management problem as analgesics and surgery are often poorly effective (Poobalan 2003; Aasvang 2005; Nienhuijs 2007). It has been demonstrated that pain following laparoscopic inguinal hernia repair may represent a more significant problem than hernia recurrence (Dickinson 2008).
Description of the intervention
Identification of methods to reduce post‐operative pain following laparoscopic inguinal hernia repair may significantly affect quality of life. Intra‐operative strategies include employing different methods of mesh fixation other than tacking or suturing which may be less traumatic to the local tissue and less likely to cause local nerve entrapment. At present, the choice of mesh fixation depends on the individual surgeons practice but, if evidence exists associating methods of mesh fixation with post‐operative complications, including post‐operative pain, this would have a significant impact on clinical practice.
How the intervention might work
Comparison of mesh fixation versus no fixation may allow a change in current surgical practice if benifit in terms of reduced post‐operative pain is demonstrated with no fixation of mesh.
Why it is important to do this review
A number of randomised trials exist to address the issue of merits of different types of mesh fixation. These methods include comparison of mesh fixation with tacks with no fixation, with fibrin glue and with suturing the mesh; although a consensus opinion regarding which method is most advantageous has not been reached. The aim of this systematic review is to determine whether there is any difference in patient outcome and morbidity when the mesh is fixed or not during laparoscopic inguinal hernia repair. We will also compare different methods of mesh fixation i.e.: no fixation, fibrin glue sealant, tacks, and sutures
Objectives
To determine whether there is any difference in patient outcome and morbidity when the mesh is fixed or not during laparoscopic inguinal hernia repair.
To compare different methods of mesh fixation i.e.: no fixation, fibrin glue sealant, tacks, and sutures.
The primary outcomes measured will be pain (inguinal or testicular), numbness and hernia recurrence.
The secondary outcome measures will be length of surgery, length of hospital stay, urinary retention, recovery time for normal activity, infection of the mesh.
Methods
Criteria for considering studies for this review
Types of studies
We will consider all randomised controlled trials comparing different methods of mesh fixation during laparoscopic inguinal hernia repair (either TEP, totally extraperitoneal or TAPP, transabdominal pre‐peritoneal) in adult patients. Trials will be included irrespective of the number of patients randomised.
Types of participants
Adults (more than 18 years old) that undergo laparoscopic inguinal hernia repair with mesh placement.
Types of interventions
Laparoscopic inguinal hernia repair with mesh fixation by i) tacks/staples or ii) sutures or iii) no fixation or iv) fibrin glue.
Types of outcome measures
Primary outcomes
The primary outcome measure will be any difference in:
i) chronic pain: pain persisting beyond three months post‐operatively
ii) persisting numbness: numbness in the groin or testicle persisting beyond three months
post‐operatively
iii) hernia recurrence: clinically or radiologically diagnosed
iv) port site hernia
Secondary outcomes
The secondary outcome measures will be:
i) length of surgery
ii) conversion to open
iii) vascular/visceral injury
iv) haematoma/seroma development
v) length of hospital stay
vi) urinary retention
vii) wound infection/mesh infection
viii) recovery time to normal activity
We will identify differences between mesh fixation v no‐mesh fixation using primary/secondary outcome measures. We also aim to identify any difference between the type of mesh fixation and these measures.
Search methods for identification of studies
Electronic searches
We will search The Cochrane Colorectal Cancer Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 10, 2010), The National Library of Medicine (PubMed) (1966 to December 2010), The Intelligent Gateway to Biomedical & Pharmacological Information (EMBASE) (1966 to December 2010) and The Latin American and Caribbean Health Sciences Library (LILACS) (1966 to December 2010).
Searching other resources
Al identified artciles will have reference lists handsearched to identify any other possible studies suitable for inclusion.
Data collection and analysis
Selection of studies
Two authors (KJD and ASF or KJD and CMW) will examine trials to determine whether they should be included, and a third evaluator (CMW or ASF) will resolve the difference in case of disagreements. KMcC will provide advice during the process. We will also list the excluded trials and reasons for their exclusion.
Data extraction and management
A form for data extraction will be developed and two authors will independently extract data and complete these forms (KJD and ASF or KJD and CMW). Data on the following will be extracted:
i) characteristics of patients: age, sex, employment (where documented), body mass index (where documented)
ii) total number of patients originally assigned to each intervention group
iii) intervention: how the mesh was fixed, if at all
iv) details of hernia repair, primary/recurrent, unilateral/bilateral, TEP/TAPP
v) length of follow up
vi) outcomes; length of operation, conversion to open, vascular/visceral injury, length of hospital stay, haematoma/seroma development, post‐operative analgesic requirements/ post‐operative pain score, wound/mesh infection, urinary retention, duration before return to activities of daily life, recurrence, chronic pain, port site hernia, persistent numbness.
Assessment of risk of bias in included studies
We will ensure that trials are assessed according to their methodological quality as overestimation of any effect observed can occur if the methodology of the trial is inadequate. The methodological quality of trials will be assessed by two authors (KJD and ASF or KJD and CMW) and a third will resolve disagreements where necessary (CMW or ASF).
If sufficient studies exist, funnel plots will be used to investigate the presence of publication bias.
Measures of treatment effect
Where appropriate odds ratios (OR) and their 95 % confidence intervals (CI) qill be calculated used the Peto odds ratio method based on the fixed effects model. For continuous variables the weighted mean difference (WMD) and 95% CI where the data are measured using the same units. Studies will be pooled usingfixed effects model.
Unit of analysis issues
This is revelevant with regard to patients with bilateral hernias. For patients with bilateral hernias the analysis will be based on the number of patients not hernias. The patient number will therefore be the denominator in these calculations.
Dealing with missing data
As a sensitivity analysis data will be analysed according to the intention to treat principle. Patients with missing final outcomes will be treated as treamnet failures.
Assessment of heterogeneity
Heterogeneity between the studies will be assessed using the chi‐squared test and the I2 statistic will be used to quantify inconsistency across the studies.
Assessment of reporting biases
We will ensure that all trials are assessed based on their methodological quality as overestimation of any effect can occur if the methodology of the trial is inadequate. The methodology of the trials will be assessed by two authors KD and ASF or KD and CMW) with the third (ASF or CMW) involved to help resolve any disputes that might occur.
Data synthesis
Data from dichotomous and continuous variables will be synthesised as described above. Assessment of heterogeneity and reporting bias have been described. If sufficient studies exist a funnel plot will be used to assess the effect of publication bias.
Subgroup analysis and investigation of heterogeneity
See above
Subgroups unilateral v bilateral and primary v recurrent hernias will be analysed
Sensitivity analysis
As a sensitivity analysis data will be analysed according to the intention to treat principle. Patients with missing final outcomes will be treated as treamnet failures
