Discussion
In the early 1970s, MPDs became standard practice following their introduction by Heerman et al. for use after temporalis fascia grafts for tympanoplasty5. MPDs were thought to be useful in stabilizing and protecting wounds, preventing contamination, providing an optimal healing environment, and absorbing secretions18-20. However, several years later, early exposure of surgical wounds open air had gained popularity in many surgical fields and many surgeons had begun to wonder whether pressure dressings were necessary at all. Along these lines, the discrepancy on the use of MPDs between otolaryngologists is not surprising in light of the absence of reliable evidence that MPDs in fact reduce rates of wound complications among adults, much less that they provide benefits which outweigh complications within the pediatric population. Our study showed no statistically significant difference between the groups either in minor or major wound complications.
This retrospective investigation was conducted to determine the efficacy of MPD application following mastoidectomies performed on children and its effect on the discomfort and pain they experience, as measured by the VAS. Our study is unique because no prior study has evaluated the need (or lack thereof) for MPDs among pediatric patients undergoing mastoidectomy for inflammatory conditions, including postoperative pain scores. For this research, postoperative, wound examination data and VAS values were compared between a group of patients who underwent mastoidectomy with MPD and a group of patients who underwent the same surgeries with no MPD.
In addition, our comparison of VAS values evidenced a significant difference between the groups, with lower levels of pain in the NMPD group. It is important to mention that the VAS values were all obtained by a single assessment (during the postoperative night, several hours before MPDs were to be removed).
Due to the retrospective nature of the study the discomfort or pain during the removal of the dressing was not evaluated. More assessments of the VAS (before, during, and after MPD removal) would have given us a better appreciation of the pain caused by its removal. It is also important to note that the VAS does not consider patients experiencing discomfort without pain, nor does it measure levels of parental stress and concern while their child’s head is covered with an MPD. Therefore, further prospective studies are needed to evaluate a more complete spectrum of pain and in a more accurate manner.
Albeit an insignificant finding, a trend toward longer lengths of stay was found in the NMPD group, a fact that may be explained by the higher percentage of mastoidectomies performed due to mastoiditis (which are typically associated with longer-term hospitalizations). This trend enhances the notion of abandoning MPD, as even with higher percentage of infectious disease as mastoiditis, fewer SSIs were seen in the NMPD group.
For the present moment, however, our findings corroborate in children the findings of previous publications on adults, that showed absence of advantages in MPD8,13,15. A prospective, randomized study conducted by Castelli et al. among 420 postauricular tympanoplasties (or tympanomastoidectomies), compared wound-related complications between patients with MPDs and those without8. There were three (3) cases of pinna bruising in the MPD group and no cases in the NMPD group. There were no hematomas or wound infections in either group, which may be attributed to the use of modern bipolar diathermy. However, unlike the current study, there was no specific reference to pediatric patients.
Previous publications in pediatric population, focused on evaluating MPD in non-inflammatory diseases. Lou et al. performed a retrospective review in pediatric cochlear implant patients and found no statistically significant difference in hematoma formation or other wound complications between the studied groups7. A prospective trial by Powell et al. to evaluate the role of head dressings in the postoperative management of the prominent ear in a plastic surgery unit also found them to be unnecessary21. Their findings are compatible with the results of this study, although as opposed to the present investigation, they gave no consideration to pain associated with MPD, as VAS values were not reported.
Further studies, such as Rewe-Jones et al., have shown not only no obvious advantages in the use of MPDs, but several disadvantages, including an increase in wound infections13. Moreover, tight dressings may cause pressure necrosis of the skin on the lateral surface of the face or pinna21.
Some of the limitations of our study was the disparity of the sample size between groups, which is explained by the fact that patients in the NMPD group were operated only in later years. Additionally, it should be taken into consideration that there may be some element of selection bias in this work due to its non-randomized, retrospective nature, particularly as each group of patients underwent surgery by a different surgeon. Nonetheless, with respect to the use of MPD, dressings were placed as per the proclivities of each surgeon and were not dependent on any patient’s condition, nor the nature and course of their surgery, so, it is possible to assume that there was equal representation of patients in both groups.