Comparison between traditional saline versus air expanders: a patient’s perspective

Tissue expansion is a widely used method of breast reconstruction. It involves periodic injection of saline via an integrated port by the physician until a desired tissue volume is reached, and final breast prostheses may be inserted. The regular injections required for conventional tissue expansion carry a risk of infection and are painful and inconvenient for patients, thus lengthening the overall time for reconstruction. These limitations also have the potential to further increase patient anxiety and distress in addition to that associated with their cancer diagnosis. We present a case series wherein seven patients underwent breast tissue expansion with both novel carbon dioxide (CO2)-based expanders (AeroForm Tissue Expander System; AirXpanders, Inc., Palo Alto, CA, USA) as well as injectable saline expanders. This is the first retrospective case series of its kind wherein each patient served as an internal case–control, enabling a more objective comparison of patient experience between the two expansion methods. In contrast to injectable tissue expansion using saline, the AeroForm expander system consists of tissue expanders paired with a patient-controlled handheld remote, allowing incremental control of CO2 delivery to each breast via an internal CO2 reservoir within the expander. Each remote device operates a single CO2 expander, allowing 10 cc of volume per dose, up to a maximum of three doses per day. An online questionnaire (Appendix S1) was given to seven patients, who had undergone both conventional saline tissue expansion and either subsequent or simultaneous AeroForm breast expansion. The questionnaire consisted of nine questions, similar to those used by Connell (http://links.lww.com/PRS/B76), which asked patients to rate their perception on a scale from 1 to 7. We also asked whether patients travelled by air with their expanders in situ, and the duration of time lapse between removal of saline expanders and insertion with AeroForm, to identify and assess potential confounders. Responses were collated anonymously via an online survey tool (SurveyHero; enuvo GmbH, Zurich, Switzerland) to tabulate individual responses. All seven patients returned completed questionnaires online. They reported the degree of softness to touch at full expansion, comfort level, ease of use, convenience, pain and overall satisfaction. The potential responses were allocated numeric grades from 1 to 7, enabling quantitative evaluation of subjective outcomes. For example, the overall level of convenience would be graded from 7 (very convenient) to 1 (very inconvenient), with a score of 4 used to represent neutrality. Our results demonstrated that the AeroForm expanders were unanimously very firm to touch (mean score = 7) and outperformed the saline expanders in the categories of ease of use and convenience. Levels of pain experienced with both expansion systems were identical (Figs S1–S3). Despite the saline expansion system having slightly higher levels of comfort and individual satisfaction scores than those of the AeroForm, the overall recommendation of expansion system was slightly in favour of AeroForm (4) over saline (3). This preference may be explained by the weight that the patients placed on each question, which influenced their overall recommendation, that is, the effect size or weight was the greatest for questions regarding firmness, ease of use and convenience. Subsequently, these attributes had the greatest impact on influencing patient preference of either expansion system and overall recommendation to future patients. Only one of the seven patients travelled by air with their AeroForm expander in situ, in contrast to three of the seven patients who had done so with their saline expander. No adverse outcomes of expansion were reported by any patient as a direct consequence of their air travel. The lapse of time between each patient’s experience of using AeroForm and saline expansion systems was variable. One patient had an AeroForm expander replaced with saline immediately. Others waited for a time period ranging from 2 weeks to 6 years, depending on recurrence of breast pathology, radiotherapy and presence of postoperative infection. For uniformity and direct comparison with previous studies, our questionnaire did not directly evaluate breast cosmesis; however, several patients have demonstrated very favourable aesthetics as a consequence of the AeroForm expansion system, comparable to those of the saline expansion system (Figs S2–S4). Each patient’s satisfaction with their post-expansion appearance could also be indirectly extrapolated from their degree of satisfaction score overall (average score of saline = 5.43 compared to AeroForm = 5.14). To date, there is evidence in the literature to support the use of air expanders over saline (Appendix S2). The results of our study, pertaining to improved comfort, ease of use and empowerment, are consistent with these previous papers. The interesting thing to note is that, although one would expect the levels of pain to be lower with use of the saline expander, we did not find this to be the case. We postulate that a longer period of time between each patient’s experience with either expansion system may have influenced their ability to recall and grade their responses in each category accurately. In addition, according to the senior author’s clinical experience with the air expander device, he reduced expansion frequency from 3 times a day to 1–2 times a day, with a subsequent decrease in levels of pain. Our study remains consistent with previous findings in that no adverse events related to air travel were reported with either expansion method, which supports the safety of CO2 in spite of the theoretical risks reported in previous literature. Our case series supports a paradigm shift towards a less invasive and more economic tissue expansion process, which will reduce arduous follow-up whilst empowering breast cancer patients to have autonomy over their choice of expansion. Our study is the first of its kind to have internal case–controls, allowing a comparison of 282 Perspectives