The outcomes of the operation for the PMR (Polypropylene Mesh Repair) and MMR (Mosquito Mesh Repair) group patients were compared. All patients and the observer (a certified general surgeon) were blinded. The same observer evaluated all of the patients before and after the operation during their follow-ups.
The observations were as follows:
In our study the most common age groups were 41-50 and 51-60 years and highest incidence in the 4th and 5th decade showing that groin hernia was more common in the middle aged population. Minimum and maximum age of the patients were 23 and 80 years respectively, with the mean age being 50.53 years, 50.38 in MMR Group and 50.68 in PPM Group showing that no age is exempted from this very common surgical problem (Table 1).
Age groups No. of patients (MMR) group % No. of patients (PMR) group % ≤ 20 0 0 0 0 21-30 07 14 6 12 31-40 07 14 9 18 41-50 11 22 10 20 51-60 12 24 10 20 61-70 10 20 13 26 71-80 3 6 2 4
Table 1. Age distribution of cases: most common age groups in both the groups were 41 –50 and 51 –60 years. Minimum and maximum ages of the patient were 23 years and 80 years respectively.
In our study, the presence of inguinal swelling was only about 60 percent and pain, in the form of dragging/pricking sensation with associated inguinal swelling, was present in 40 percent of the cases (Table 2).
Clinical presentation No. of cases Percentage % Inguinal Swelling alone 60 60 Inguinal Swelling with discomfort 40 40 Total 100 100
Table 2. Clinical presentation: 60 patients complained of inguinal swelling alone and 40 complained of inguinal swelling with discomfort
In our study of 100 patients, majority of patients (82%) had an indirect inguinal hernia and 18% had a direct inguinal hernia. All of the bilateral hernias were direct.
In terms of site of hernia, we found that there was a definite right sided preponderance (60%) of cases, with left being (34%) and (6%) being bilateral. The bilateral cases were operated on one side only, the site decided by the surgeon as more symptomatic and the patient was assigned to only one group (Table 3).
Type of hernia MNM group PPM group Combined R L R L R L R L R L R L Frequency % Frequency % Frequency % Indirect total 28 10 56 20 26 18 52 36 54 28 54 28 38 76 44 88 82 82 Direct total 4 4 8 8 2 2 4 4 6 6 6 6 8 16 4 8 12 12 Bilateral direct 4 8 2 4 6 6 Total 50 100 50 100 100 100 Total cases = 100
Table 3. Distribution of cases with respect to type of hernia
All of the patients were discharged from the hospital as soon as they became ambulant and tolerated orals. Patients in both groups were advised to exercise early ambulation. Orals were started as soon as when the post-operative nausea was over and the patient began to feel hungry, usually after six hours in patients who underwent general anesthesia, and as early as 1 –3 hours in patients with spinal anesthesia or local anesthesia. In our study the mean post-operative hospital stay was 1.22 days (range 1 –3 days) for the MNM and 1.20 (range 1 –3 days) for the PPM group, with no statistical significance between the groups. The overall mean post-operative hospital stay in days was 1.21 days (Table 5).
Postoperative hospital stay (in days) MNM group PPM group No. of cases % No. of cases % 1 38 76 39 68 2 11 22 10 20 3 1 2 1 2 Total 50 100 50 100 P>0.05 (NS), NS: non significant.
Table 5. Hospital stay
Complications 1. Wound infection—In the MMR Group, four patients (8%) developed wound infection. In the PMR Group, three patients (6%) developed wound infection. In no case the mesh was removed. It was classified as surgical site infection superficial type.
2. Wound seroma —In the MMR Group, two patients (4%) developed wound seroma and in PMR, two patients (4%) developed wound seroma.
3. Wound hematoma—In the MMR Group, one patient (2%) developed wound hematoma and in the PMR Group, two patients (4%) developed a wound hematoma.
4. Urinary retention—In both Groups, one patient (2%) had an episode of urinary retention which was managed by catheterization in MMR group.
5. Chronic pain—One patient in each group developed persistent chronic pain in the inguinal region and were classified as chronic groin pain post hernia repair. Both were treated showed improvement during follow up.
6. Inguinal paresthesia—In the MMR Group, one patient (2%) had inguinal paresthesia. Presently, he is undergoing follow-ups.
The patients were being followed up at intervals of two weeks, two months, six months, one year, one and a half year and two years. It was not seen in either groups in our study until December of 2012.
The average time to return to work (non-strenuous) was 13.30 days in the PPM group and 13.68 days in the PPM group. Overall mean time to return to work was 13.49 days for both groups. There was no statistically significant difference between two groups
The modern age of hernia repair began in 1958 when American surgeon Usher et al., described hernia repair using Marlex mesh to provide a tension-free repair that became popular due to its minimal invasiveness. Since then, Hernia surgery has got revolutionized. Mesh acts as "scaffolding" for new growth of a patient's own tissue, which eventually incorporates the mesh into the surrounding area. Mesh is used in both tension-free and laparoscopic tension-free hernia repairs. Mesh is generally available in various measurements and can often be cut to size.
In industrialized countries, alloplastic meshes are routinely used for hernia repair but in developing countries these are rarely available or affordable. In India, the imported PPM is available and a (7.5×15) cm mesh costs Rs 1666/USD $36.22; the (15×15) cm mesh costs Rs 3724/USD $80.96, and the (30×30) cm mesh costs Rs 9430/USD $205. In 1996, Indian surgeons found a polyethylene PPM, in the form of mosquito net mesh, a useful cost-effective alternative to standard meshes.
M. G. Clarke et al., in Ghana, reported the use of sterilized polyester PPM for inguinal hernia repair in ninety-five (95) patients, using a total of 106 polyester PPMes. A trial in Burkina Faso which used a similar cheap nylon mosquito mesh has proven that there was no significant difference in the clinical short-term outcome of the hernia treatment or the surgeons comfort in handling the two different materials. Sebastian Freudenberg et al., reported no severe complications while using the sterile nylon mosquito net versus the use of a commercial mesh for hernia repair in a randomized double-blind study in Burkina Faso..
Sanders et al., revealed using vibrational spectroscopy that the material and mechanical properties of the Polyethylene Mosquito net are substantially equivalent to those of commonly used lightweight commercial meshes. This study has revealed the macromolecular structure of the PPM. The Mosquito net is a polyethylene homopolymer, knitted from monofilament fibers with a mean filament diameter of 109.7 μm and a mean mesh thickness of 480 μm. The mean pore maximum diameter is 1.9 mm, with 91.2% porosity, 53.7 g/m2 mean mesh weight, and a linear mass density of 152 denier. This is comparable to the "large pore" (class Ⅰ) commercial meshes. The bursting force for Polyethylene Mosquito net is greater than for UltraPro and Vypro (43.0 vs. 35.5 and 27.2 N/cm, respectively), and the Mosquito net exhibited less anisotropy compared to the commercial meshes.
Another recent study has revealed that in vitro infection risk of using the Polyethylene Mosquito net is not significantly different from commonly used monofilament polypropylene commercial prosthetics and is in fact lower than a commonly used commercial multifilament mesh. This study adds to the growing body of evidence that indicates that these meshes can be safely deployed.
Thus it could be concluded that the cheap indigenous PPM which has similar properties of an imported mesh can be safely used for tension-free inguinal hernia repair in adults and without any additional financial burden to the patient and should be considered the standard of care for treating inguinal hernias, especially, in the poor patients who cannot afford the imported PPM. Further trials with a larger number of patients and longer follow-ups are justified and recommended.
Cost effective use of Mosquito net mesh in inguinal hernia repair
- Received Date: 2018-11-30
- Accepted Date: 2018-11-30
- Available Online: 2019-09-01
Abstract: Mesh hernia repair is one of the commonest among the open techniques of inguinal hernia repair. The main limiting factor in the use of new meshes is the cost. We carried out a prospective randomized double blind study and comprising of a hundred patients with 100 inguinal hernias admitted consecutively for elective surgery, divided into Group 1 (Polypropylene mesh, PPM) and Group 2 (Mosquito net mesh, MNM) each containing fifty patients. All cases were completed successfully and results revealed no difference in two groups. The results of the present study, in consistent with the published literature, reveal that the cheap indigenous Mosquito mesh, which has similar properties of an imported mesh, can be safely used for tension-free inguinal hernia repair in adults. Further trials with a larger number of patients and longer follow-ups are justified and recommended.