The Biomechanics and Optimization of the Needle-Syringe System for Injecting Triamcinolone Acetonide into Keloids.

Purpose. Injecting triamcinolone acetonide (TA) into a keloid is physically challenging due to the density of keloids. The purpose was to investigate the effects of various syringe and needle combinations on the injection force to determine the most ergonomic combination. Materials and Methods. A load cell was used to generate and measure the injection force. Phase 1: the injection force of 5 common syringes was measured by injecting water into air. The syringe that required the lowest injection force was evaluated with various needle gauges (25, 27, and 30 G) and lengths (16, 25, and 38 mm) by injecting TA (40 mg/mL) into air. The needle-syringe combination with the lowest injection force (CLIF) was deemed the most ergonomic combination. Phase 2: comparisons between the CLIF and a standard combination (SC) were performed by injecting TA into air and tap water into a keloid specimen. Intraclass Correlation Coefficient (ICC) and independent t-test were used. Results. Increasing the syringe caliber, injection speed, and needle gauge and length significantly increased the injection force (p value < 0.001). The SC required a maximum force of 40.0 N to inject water into keloid, compared to 25.0 N for the CLIF. Injecting TA into keloid using the SC would require an injection force that was 103.5% of the maximum force female thumbs could exert compared to 64.8% for the CLIF. ICC values were greater than 0.4. Conclusions. The 1 mL polycarbonate syringe with a 25 G, 16 mm needle (CLIF) was the most ergonomic combination. The SC required a substantial injection force, which may represent a physical challenge for female thumbs.

Post-breast surgery pain syndrome: establishing a consensus for the definition of post-mastectomy pain syndrome to provide a standardized clinical and research approach - a review of the literature and discussion.

BACKGROUND: Post-mastectomy pain syndrome (PMPS) is a frequent complication of breast surgery. There is currently no standard definition for this chronic pain syndrome. The purpose of this review was to establish a consensus for defining PMPS by identifying the various elements included in the definitions and how they vary across the literature, determining how these definitions affect the methodological components therein, and proposing a definition that appropriately encompasses all of the appropriate elements. METHODS: We searched PubMed to retrieve all studies and case reports on PMPS, and we analyzed definitions of PMPS, inclusion/exclusion criteria, and methods of measuring PMPS. RESULTS: Twenty-three studies were included in this review. We identified 7 independent domains for defining PMPS: surgical breast procedure, neuropathic nature, pain of at least moderate intensity, protracted duration, frequent symptoms, appropriate location of the symptoms and exacerbation with movement. These domains were used with varying frequency. Inclusion/exclusion criteria and methods for assessing PMPS also varied markedly. CONCLUSION: To prevent future discrepancies in both the clinical and research settings, we propose a new and complete definition based on the results of our review: PMPS is pain that occurs after any breast surgery; is of at least moderate severity; possesses neuropathic qualities; is located in the ipsilateral breast/chest wall, axilla, and/or arm; lasts at least 6 months; occurs at least 50% of the time; and may be exacerbated by movements of the shoulder girdle.

CONTEXTE: Le syndrome douloureux post-mastectomie (SDPM) est une complication fréquente de la chirurgie mammaire. Actuellement, il n'existe aucune définition unique de cette douleur chronique. Le but de la présente revue était donc d'élaborer une définition consensuelle du SDPM en dégageant les différents éléments définitoires, en observant leur variation dans les différentes sources, en déterminant comment ces variations influent sur la méthodologie utilisée, puis en proposant une définition qui met correctement en relation tous les éléments pertinents. MÉTHODES: Nous avons cherché dans PubMed toutes les études et études de cas sur le SDPM. Nous avons ensuite analysé les définitions du syndrome, ses critères d'inclusion et d'exclusion et ses méthodes d'évaluation. RÉSULTATS: La présente revue repose sur 23 études. Nous avons mis en évidence 7 éléments indépendants servant à définir le SDPM : l'intervention de chirurgie mammaire, la nature neuropathique de la douleur, la présence d'une douleur au minimum d'intensité modérée, la persistance des symptômes, leur fréquence élevée, leur localisation ainsi que leur exacerbation due au mouvement. La prise en compte de ces éléments dans les différentes définitions était variable; des variations importantes ont aussi été observées dans les critères d'inclusion et d'exclusion ainsi que dans les méthodes d'évaluation. CONCLUSION: Pour prévenir les différences conceptuelles, autant dans les milieux cliniques que dans les milieux de recherche, nous proposons une définition originale et complète fondée sur les résultats de notre revue. Le SDPM est une douleur qui apparaît à la suite d'une chirurgie mammaire, peu importe sa nature; est au minimum d'intensité modérée; est de nature neuropathique; est localisée dans le sein, la paroi thoracique, l'aisselle ou le bras ipsilatéraux; persiste au moins depuis 6 mois; est présente au moins 50 % du temps; et peut être exacerbée par les mouvements de la ceinture scapulaire.

Clinical research in aesthetic surgery.

Clinical research in aesthetic surgery cannot use traditional objective measures of surgical success. Present research designs and methods used in aesthetic surgery limit the ability to conduct meaningful clinical research. Outcomes research may be ideally suited for assessing patients in aesthetic surgery. A critical aspect of an outcomes-based approach is to select appropriate instruments for investigations. Widely accepted, standardized methods for assessing outcomes would allow for comparison of surgical techniques and provide a common basis for clinical investigations.

The use of cost-effectiveness analysis in plastic surgery clinical research.

The goal of this article is to introduce clinical investigators to the basic concepts of cost-effectiveness analysis. This line of research is not commonly pursued in clinical studies probably because of unfamiliarity of plastic surgeons with the field of health economics and health research methodology in general. The authors believe that the coupling of cost-effectiveness analysis with clinical studies is important and should be incorporated into surgical clinical research.

Comparison of the deep inferior epigastric perforator flap and free transverse rectus abdominis myocutaneous flap in postmastectomy reconstruction: a cost-effectiveness analysis.

This study compared the deep inferior epigastric perforator (DIEP) flap and the free transverse rectus abdominis myocutaneous (TRAM) flap in postmastectomy reconstruction using a cost-effectiveness analysis. A decision analytic model was used. Medical costs associated with the two techniques were estimated from the Ontario Ministry of Health Schedule of Benefits for 2002. Hospital costs were obtained from St. Joseph's Healthcare, a university teaching hospital in Hamilton, Ontario, Canada. The utilities of clinically important health states related to breast reconstruction were obtained from 32 "experts" across Canada and converted into quality-adjusted life years. The probabilities of these various clinically important health states being associated with the DIEP and free TRAM flaps were obtained after a thorough review of the literature. The DIEP flap was more costly than the free TRAM flap ($7026.47 versus $6508.29), but it provided more quality-adjusted life years than the free TRAM flap (28.88 years versus 28.53 years). The baseline incremental cost-utility ratio was $1464.30 per quality-adjusted life year, favoring adoption of the DIEP flap. Sensitivity analyses were performed by assuming that the probabilities of occurrence of hernia, abdominal bulging, total flap loss, operating room time, and hospital stay were identical with the DIEP and free TRAM techniques. By assuming that the probability of postoperative hernia for the DIEP flap increased from 0.008 to 0.054 (same as for TRAM flap), the incremental cost-utility ratio changed to $1435.00 per quality-adjusted life year. A sensitivity analysis was performed for the complication of hernia because the DIEP flap allegedly diminishes this complication. Increasing the probability of abdominal bulge from 0.041 to 0.103 for the DIEP flap changed the ratio to $2731.78 per quality-adjusted life year. When the probability of total flap failure was increased from 0.014 to 0.016, the ratio changed to $1384.01 per quality-adjusted life year. When the time in the operating room was assumed to be the same for both flaps, the ratio changed to $4026.57 per quality-adjusted life year. If the hospital stay was assumed to be the same for both flaps, the ratio changed to $1944.30 per quality-adjusted life year. On the basis of the baseline calculation and sensitivity analyses, the DIEP flap remained a cost-effective procedure. Thus, adoption of this new technique for postmastectomy reconstruction is warranted in the Canadian health care system.

Should the donor radius be plated prophylactically after harvest of a radial osteocutaneous flap? A cost-effectiveness analysis.

The objective of this study was to assess the cost-effectiveness of prophylactic plating of the donor radius after harvest of a radial osteocutaneous flap. Costs were measured from a Ministry of Health perspective, and effectiveness in terms of quality adjusted life years (QALYs.) A literature search identified 22 studies reporting complications of radial osteocutaneous free flaps, and nine studies reporting complications of radius plating. The rates of the various complications were pooled to provide the probability of each clinically important complication. A decision analytic model was used to determine the total costs, and QALYs for each of the treatment options. The expected direct costs for prophylactic plating and treatment after fracture were $2071 and $140, respectively. The expected QALYs for prophylactic plating and treatment after fracture were 8.55 and 9.92, respectively. It was concluded that prophylactic plating of the donor radius is not a cost-effective approach when compared to the treatment of donor radius fractures after they occur.

Cost-utility analysis comparing free and pedicled TRAM flap for breast reconstruction.

The purpose of this study was to compare the free TRAM to the unipedicled TRAM flap in postmastectomy reconstruction, using a cost-utility analysis. A decision analytic model was used for this study. Medical costs associated with the two techniques were estimated from the Ontario Ministry of Health Schedule of Benefits (1998). Hospital costs were obtained from St. Joseph's Healthcare, a university hospital in Hamilton, Ontario. Utilities were obtained from 33 "experts" across Canada and then converted into quality-adjusted life-years (QALYs). The probabilities of various health states associated with unipedicled and free TRAM flaps were obtained by reviewing several key articles. The free TRAM flap was more costly than the unipedicled TRAM flap, but it provided more QALYs. The baseline incremental cost-utility ratio (ICUR) was $5,113.73/QALY, favoring adoption of the free TRAM flap. This study showed that the free TRAM flap is a cost-effective procedure for postmastectomy reconstruction in the Canadian healthcare system.