Probabilistic Risk Assessment of Prophylactic Surgery Before Extended-Duration Spaceflight

Interval Appendectomy After Successful Antibiotic Treatment?

This Viewpoint discusses the pros and cons of performing interval appendectomy in patients who have recovered from successful antibiotic treatment of acute uncomplicated appendicitis.

Surgery in the Next Space Missions

In the coming years, missions to the Moon and Mars shall be the new goals of space flight. The complexity of these missions due to the great distance from Earth and the unforeseen obstacles to settle on another planet have given rise to great concerns for crew health and survival. The need for advanced crew autonomy and a different approach to surgical emergency require new protocols and devices to help future crew medical officers and other crew members in a task of unprecedented difficulty. Hence, the increasing variety of schedules, devices, and protocols being developed. A serious health problem, such as an emerging surgical disease or severe trauma, can jeopardize the mission and survival of the entire crew. Many other difficulties are present in deep-space missions or settlements on other planets, such as communication and supply, also medical, delays, and shortage, and the presence of radiation. Progress in advanced technologies as well as the evolution of robotic surgery and the use of artificial intelligence are other topics of this review. In this particular area of research, even if we are still very far from an "intelligent robot", this evolution must be evaluated in the light of legislative and ethical considerations. This topic was presented at the annual meeting of the American College of Surgeons-Italy Chapter in 2021.

Just-in-time Training with Remote Guidance for Ultrasound-Guided Percutaneous Intervention

BACKGROUND: Management of surgical emergencies in spaceflight will pose a challenge as the era of exploration class missions dawns, requiring increased crew autonomy at a time when training and supplies will be limited. Ultrasound-guided percutaneous intervention would allow for the management of a variety of pathologies with largely shared equipment and training. This proof-of-concept work attempts to determine the feasibility of "just-in-time" remote teaching and guidance of a sample procedure of this type.METHODS: Subjects naïve to ultrasound-guided intervention were instructed via a short video regarding the technique for placement of a percutaneous drain into a simulated abscess within a gel phantom. Subjects were then guided through the performance of the procedure via two-way audiovisual communication with an experienced remote assistant. Technical success was determined by the successful aspiration or expression of fluid from the simulated abscess following drain placement. This was then performed by and compared with staff experienced with such procedures. Time to completion and number of needle redirections required were also measured.RESULTS: All 29 subjects naïve to interventional work and the 4 experienced control subjects achieved technical success. There was a statistically significant difference in the time to completion between the two groups, with the experienced subjects averaging 2 min to completion and the inexperienced 5.8 min. There was no statistically significant difference in the number of redirections.DISCUSSION: This proof-of-concept work demonstrates high rates of technical success of percutaneous ultrasound-guided intervention in previously inexperienced personnel when provided with brief just-in-time training and live two-way audiovisual guidance.Lerner DJ, Pohlen MS, Apland RC, Parivash SN. Just-in-time training with remote guidance for ultrasound-guided percutaneous intervention. Aerosp Med Hum Perform. 2022; 93(12):882-886.

Spatial Volume Necessary to Perform Open Appendectomy in a Spacecraft

BACKGROUND: With the increase in crewed commercial spaceflight and expeditions to the Moon and Mars, the risk of critical surgical problems and need for procedures increases. Appendicitis and appendectomy are the most common surgical pathology and procedure performed, respectively. The habitable volume of current spacecraft ranges from 4 m3 (Soyuz) to 425 m3 (International Space Station). We investigated the minimum volume required to perform an appendectomy and compared that to habitable spacecraft volumes.METHODS: The axes of a simulated operating room were marked and cameras placed to capture movements. An expert surgeon, chief surgical resident, junior surgical resident, and a nonsurgeon physician each performed a Focused Assessment with Sonography for Trauma and an appendectomy on a simulated patient. Dimensions and volume needed were collected and compared using unpaired t-tests.RESULTS: Mean volume (± SD) needed was 3.83 m3 ± 0.47 m3 for standing and 3.68 m3 ± 0.49 m3 for kneeling (P = 0.638). Minimal volume needed was 3.20 m3 for standing and 3.26 m3 for kneeling. Minimal theoretical volume was 2.99 m3 for standing and 2.87 m3 for kneeling.DISCUSSION: The unencumbered volume needed for an appendectomy is between 2.87 m3 and 4.3 m3. It may be technically feasible to perform an open appendectomy inside the smallest of currently operating spacecraft, at 4 m3 (Soyuz-MS). Space vessels operating without rapid evacuation to Earth will need to consider this volume for potential surgical emergencies. Additional investigation on microgravity and standardization of procedures for novices must be completed.Kamine TH, Siu M, Kramer K, Kelly E, Alouidor R, Fernandez G, Levin D. Spatial volume necessary to perform open appendectomy in a spacecraft. Aerosp Med Hum Perform. 2022; 93(10):760–763.

Appendix and Ulcerative Colitis: a Key to Explaining the Pathogenesis and Directing Novel Therapies?

The vermiform appendix is generally considered a redundant organ, but recent evidence suggests that the appendix could contribute to the pathogenesis of inflammatory bowel diseases, in particular ulcerative colitis (UC), and may even have a therapeutic role; however, mechanisms of the appendix involvement remain unclear. Here, we highlight current evidence on the link between the appendix and UC and consider plausible therapeutic implications. A literature search was conducted using PubMed and PubMed Central from inception to Nov 2021 using the terms "Appendix", "UC", "Appendix & UC," "Appendectomy", and "Peri-appendicular patch," including only articles published in English. Reference lists from the selected studies were manually searched and reviewed to gather additional related reports. Inflammation around the appendix ("peri-appendicular patch") has been frequently observed in UC patients without other cecal involvement, and this inflammation can even precede the onset of UC. Epidemiologic studies propose that appendectomy reduces the risk of developing UC or even the risk of flare after UC is diagnosed, although this remains controversial. We reviewed studies showing altered host-microbe interactions in the appendix in UC, which suggest that the appendix could act as a priming site for disease via alterations in the immune response and changes in microbiota carried distally to the colon. In summary, recent literature suggests a possible role for microbes and immune cells within the appendix; however, the role of the appendix in the pathogenesis of UC remains unclear. Further research could clarify the therapeutic potential related to this organ.