Hallbeck, M. Susan

Deep inferior epigastric perforator (DIEP) flap is a surgical procedure using tissue harvested from the abdominal area to reconstruct the breast after a mastectomy. Primary surgical phases include the abdominal flap harvest, chest dissection, and anastomosis. In this study, inertial measurement units (IMUs) were used to measure surgeon upper body postures while performing DIEP flap procedures. Ergonomic risks of musculoskeletal disorders were evaluated using the Rapid Upper Limb Assessment (RULA) based on the postures obtained from the IMUs. Joint angles were analyzed using a one-way ANOVA. The neck and back had higher joint angles during the abdominal flap (M=32°, 17°, respectively) and chest dissection (M=31°, 18°, respectively) phases than the anastomosis phase. These high-risk postures may lead to musculoskeletal disorders. Future interventions should focus on improving the postures of the neck and back during the abdominal flap and chest dissection phases of the procedure.

ABSTRACTIntroductionSuccessful tourniquet application increases survival rate of exsanguinating extremity hemorrhage victims. Tactile feedback during tourniquet application training should reflect human tissue properties in order to increase success in the field. This study aims to understand the mechanical properties of a human limb during tourniquet application.MethodSix cadaveric extremities—three uppers and three lowers—were tested from three body mass index groups: low (<19) healthy (19-24), and overweight (>24). Each specimen donned with a tourniquet and mounted to a servo-hydraulic testing machine, which enabled controlled tightening of the tourniquet while recording the tourniquet tension force and strap displacement. A thin-film pressure sensor placed between the specimen and the tourniquet recorded contact pressure. Each limb was tested with the tourniquet applied at two different sites resulting in testing at the upper arm, forearm, thigh, and shank.ResultsThe load displacement curves during radial compression were found to be nonlinear overall, with identifiable linear regions. Average contact pressure under the tourniquet strap at 200N and 300N of tension force was 126.3 (σ = 41.2) mm Hg and 205.3 (σ = 75.3) mm Hg, respectively. There were no significant differences in tissue stiffness or contact pressure at 300N of tension force between limb (upper vs. lower) or body mass index. At 200N of tension, the upper limb had significantly higher contact pressure than the lower limb (P = 0.040). Relative radial compression was significantly different between upper (16.74, σ = 4.16%) and lower (10.15, σ = 2.25%) extremities at 200N tension (P = 0.005).ConclusionsSimulation of tissue compression during tourniquet application may be achieved with a material exhibiting elastic properties to mimic the force-displacement behavior seen in cadaveric tissue or with different layers of material. Different trainers for underweight, healthy, and overweight limbs may not be needed. Separate tourniquet training fixtures should be created for the upper and lower extremities.

Studies utilizing a systems perspective show that individual work system elements impact surgeon workload. However, limited work has shown how multiple elements together can affect perceived workload in the healthcare domain. Using NASA-Task Load Index (NASA-TLX), this study aimed to compare operating room workload across two work system factors (surgical specialty and case number of the day) using a large set of self-reported surgeon workload data. Thirty-two surgeons completed 545 workload surveys across a three month period. Surgeons reported significant differences in composite workload scores across the surgical specialties (F(7,544)=3.622, p=0.001). Significant interactions were identified between surgical specialty and case number for composite workload, F(20,534)=1.72, p=0.027. While such findings are promising, future work is needed across multiple institutions to establish baseline workload values across specialties with different patient characteristics and work systems.

There is a growing awareness of the physical demands of performing surgery and the need for ergonomic education and training, extending beyond the primary surgeon to other members of the surgical team who are also at risk for musculoskeletal injury. In this study, nine Surgical First Assistants received knowledge-based ergonomic education before their body postures were evaluated using inertial measurement units in an anatomy training lab setting and again in the operating room (OR). Five of those trainees comprised the intervention group, receiving a personalized report detailing their level of ergonomic risk, while the other four did not receive this individual feedback. The intervention group significantly improved their neck and left arm posture during the anatomy lab training with carryover into the OR, indicating some retention of ergonomic concepts, while the control group did not. The integration of wearable technology and individualized feedback into traditional educational settings helped trainees learn about their own behaviors and practice strategies for reducing risks in the OR with greater retention compared to knowledge-based education alone.

The purpose of this panel will be to discuss current research and challenges relating to the work of first and immediate responders. The main discussion of the panel will have panelist challenge human factors researchers to consider new directions of research addressing current capability and knowledge gaps faced by the first and immediate responder communities.

The use of lead vest/aprons in interventional medicine has been identified in self-report surveys as a contributing factor to the development of occupational low back pain. Controlled studies (both laboratory and field) that have explored this association have not provided a conclusive link. This review explores the knowledge and gaps surrounding the use of lead vest/apron and low back pain development.

Background: Laparoendoscopic single site surgery (LESS) is feasible for more complex procedure types, but the technical challenges and learning curve posed by LESS makes traditional multi-incision laparoscopy still the preferred technique. The aims of this study were to understand the restricted mobility and positional requirements of these more complex procedures and to generate innovative instrument designs to overcome these restrictions. Methods: A two-phase study was conducted where three lightly-embalmed (fresh tissue) cadavers were utilized to estimate in vivo mobility restriction and positional requirements. These data were combined to quantifying instrument force and positional requirements to develop a novel design for a LESS-specific grasper. Results: The LESS-specific has an ergonomic curved axial handle and locking mechanism that enables surgeons to relax their grip without the grasper releasing. Conclusion: Further design adaptations are needed to optimize the size, angles, and curvature of the tool, as well as to add two points of articulation for rapid intracorporeal adjustment.

In laparoscopy, novel three-dimensional laparoscopic vision systems (3D LVS) without glasses (3D−) have been invented. While standard 3D LVS with glasses (3D+) have shown advantages over original two-dimensional systems, quantitative comparisons of surgical performance between 3D− and 3D+ systems are still lacking. The aim is to compare the systems in simulated robotic surgery tasks. In a crossover study, 18 medical students performed four basic laparoscopic tasks in the validated Simball Box simulator with authentic surgical instruments by using the 3D+ and 3D− systems. Performance was measured by the number of errors and the task’s duration. Subjective ratings of perceptions and preference were assessed after each test. There were significant, but still minor, advantages for the conventional 3D+ system regarding spatial orientation and sense of depth. Overall, ten and eight subjects preferred 3D+ and 3D− systems, respectively. No significant differences were found in performance, post-operative physicals or eye symptoms. The novel 3D− system was similar to the conventional 3D+ system regarding performance and overall preference, while there were minor advantages for the 3D+ system in the subjective ratings. Since the 3D− system is a new invention, it should have a higher potential of usability improvements.