INTRODUCTION:Sarcopenia is a known risk factor for adverse outcomes across multiple disease states, including severe trauma. Factors such as age, hyperinflammation, prolonged immobilization, and critical illness may not only exacerbate progression of this disease but may also contribute to the development of induced sarcopenia, or sarcopenia secondary to hospitalization. This study seeks to (1) determine the effects of severe traumatic injury on changes in skeletal muscle mass in older adults; (2) test whether changes in skeletal muscle mass are associated with clinical frailty, physical performance, and health-related quality of life; and (3) examine trauma-induced frailty and temporal changes in myokine and chemokine profiles. METHODS:A prospective, longitudinal cohort study of 47 critically ill, older (≥45 years) adults presenting after severe blunt trauma was conducted. Repeated measures of computed tomography-based skeletal muscle index, frailty, and quality of life were obtained in addition to selected plasma biomarkers over 6 months. RESULTS:Severe trauma was associated with significant losses in skeletal muscle mass and increased incidence of sarcopenia from 36% at baseline to 60% at 6 months. Severe trauma also was associated with a transient worsening of induced frailty and reduced quality of life irrespective of sarcopenia status, which returned to baseline by 6 months after injury. Admission biomarker levels were not associated with skeletal muscle index at the time points studied but demonstrated distinct temporal changes across our entire cohort. CONCLUSIONS:Severe blunt trauma in older adults is associated with increased incidence of induced sarcopenia and reversible induced frailty. Despite muscle wasting, functional decline is transient, with a return to baseline by 6 months, suggesting a need for holistic definitions of sarcopenia and further investigation into long-term functional outcomes in this population.

Multiple organ failure (MOF) emerged in the early 1970s with the advent of intensive care units (ICUs). Sepsis and trauma were recognized to be the primary inciting events. MOF was initially viewed to be “fatal expression of uncontrolled infection” caused by intra-abdominal infection. As a result, research focused on preventing IAIs as well and stress formula TPN to prevent the resulting “septic auto-cannibalism”. In the mid-1980s, it was shown that blunt trauma frequently induced a non-infectious “sepsis syndrome” phenotype. Research efforts focused on identifying the driving mechanisms. Unrecognized shock was identified and it became a common ICU practice to maximize oxygen delivery to eliminate “oxygen debt”. In the late 1980s, tremendous advances in trauma care resulted in decreased early deaths. However, an epidemic of iatrogenic abdominal compartment syndrome (ACS) emerged as a new phenotype. Simultaneously, “sepsis syndrome” was replaced by the SIRS/CARS paradigm to explain the bimodal presentation on early and late MOF. In the late 1990s, again fundamental advances in trauma care reduced early deaths, but largely eliminated ACS. In the 2000s, implementing the Glue Grant trauma and the Surviving Sepsis Campaign evidence based guidelines in surgical ICU substantially decreased ICU deaths from MOF. However, MOF had evolved into a lingering phenotype of chronic critical illness (CCI). The term persistent inflammation, immunosuppression, and catabolism syndrome (PICS) was coined to describe the new phenotype and to provide a mechanistic framework in which to study CCI in surgical ICU patients. A recently completed 5 year prospective study of surgical ICU sepsis demonstrated that while ICU deaths were surprising low, over a 1/3rd of patients progressed into CCI. Roughly, 80% of CCI patients had a poor discharge disposition suffering from severe disabilities and a 1 year mortality of 40%. Serial biomarkers out to 28 days validated the PICS–CCI paradigm.

In Brief Export A review of UF SCIRC’s research efforts characterizing CCI, PICS biomarkers, effect of site of infection, acute kidney injury, effects on older patients, dysfunctional high-density lipoproteins, sarcopenia/cachexia, emergency myelopoiesis, and dysregulated erythropoiesis.

INTRODUCTION:Survivors of sepsis will progress towards rapid recovery (RAP) or enter a state of persistent organ dysfunction and chronic critical illness (CCI). Independently, anemia is known to be a significant factor in functional recovery of hospitalized patients. This study aims to analyze long-term hemoglobin levels and functional outcomes following RAP and CCI. METHODS:A prospective, cohort study was performed in septic patients who were stratified into RAP (N = 54) with ICU length of stay < 14 days or CCI (N = 63) with ICU length of stay > 14 days. CBC and plasma inflammatory markers were measured on the day of enrollment, weekly until day 42, then at 3 and 6 months. Functional outcomes using Zubrod scale, gait speed test, and total short physical performance battery (SPPB) were assessed at 3, 6, and 12 months. RESULTS:Mean age was 59 years (range: 20-83) and 62% were male. Hemoglobin was significantly decreased at 3 and 6 months in CCI compared to RAP (8.9* and 9.2* vs 10.4 and 11.1 g/dL), despite receiving significantly more red blood cell transfusions. CCI patients had persistent elevation of CRP, IL-6 and TNF-α. CCI patients had worse functional outcome with a significantly higher Zubrod score, and lower SPPB, and gait speed score at 3, 6, and 12 months. CONCLUSION:Despite receiving more pRBC transfusions, CCI patients had a persistent anemia that was associated with chronic systemic inflammation and poor functional outcomes six months following sepsis. Alleviating prolonged inflammation could improve persistent anemia and functional outcomes in CCI patients.

BACKGROUND:Sepsis-induced gut microbiome alterations contribute to sepsis-related morbidity and mortality. Given evidence for improved postsepsis outcomes in females compared with males, we hypothesized that female mice maintain microbiota resilience versus males. METHODS:Mixed-sex C57BL/6 mice underwent cecal ligation and puncture (CLP) with antibiotics, saline resuscitation, and daily chronic stress and were compared with naive (nonsepsis/no antibiotics) controls. For this work, the results of young (3-5 months) and old (18-22 months) adult mice were analyzed by sex, independent and dependent of age. Mice were sacrificed at days 7 and 14, and 16S rRNA gene sequencing was performed on fecal bacterial DNA. α and β diversity were determined by Shannon index and Bray-Curtis with principal coordinate analysis, respectively. False discovery rate (FDR) correction was implemented to account for potential housing effect. RESULTS:In control mice, there was no difference in α or β diversity between male and female mice (FDR, 0.76 and 0.99, respectively). However, male mice that underwent CLP with daily chronic stress had a decrease in microbiota α diversity at 7 days post-CLP (Shannon FDR, 0.005), which was sustained at 14 days post-CLP (Shannon FDR, 0.001), compared with baseline. In addition, male mice maintained differences in β diversity even at day 14 compared with controls (FDR, <0.0001). In contrast, female mice had a decreased microbiota α diversity (Shannon FDR, 0.03) and β diversity (FDR, 0.02) 7 days post-CLP but recovered their α and β diversity by post-CLP day 14 (Shannon FDR, 0.5, and FDR, 0.02, respectively). Further analysis of females revealed that only young female mice were not different (β diversity) post-CLP day 14 to controls. CONCLUSION:Although sepsis-induced perturbations of the intestinal microbiota occur initially in both male and female C57BL/6 mice, females demonstrate different microbiota by day 14. This may be seen primarily in younger females. This difference in recovery may play a role in outcome differences between sexes after sepsis.

Skin and soft-tissue infections (SSTIs) encompass a variety of pathological conditions that involve the skin and underlying subcutaneous tissue, fascia, or muscle, ranging from simple superficial infections to severe necrotizing infections. Together, the World Society of Emergency Surgery, the Global Alliance for Infections in Surgery, the Surgical Infection Society-Europe, The World Surgical Infection Society, and the American Association for the Surgery of Trauma have jointly completed an international multi-society document to promote global standards of care in SSTIs guiding clinicians by describing reasonable approaches to the management of SSTIs. An extensive non-systematic review was conducted using the PubMed and MEDLINE databases, limited to the English language. The resulting evidence was shared by an international task force with different clinical backgrounds.

Central MessagePosttraumatic pneumonectomy is a highly morbid and lethal event. Postoperative use of venovenous ECMO and serial washouts for a contaminated pleural space is an effective treatment strategy.See Commentary on page 280.Posttraumatic pneumonectomy is a rare event that carries extremely high morbidity and mortality.1Homo R. Grigorian A. Lekawa M. Dolich M. Kuza C. Doben A. et al.Outcomes after pneumonectomy versus limited lung resection in adults with traumatic lung injury.Updates Surg. 2020; 72: 547-553Crossref PubMed Scopus (3) Google Scholar, 2Matsushima K. Aiolfi A. Park C. Rosen D. Strumwasser A. Benjamin E. et al.Surgical outcomes after trauma pneumonectomy.J Trauma Acute Care Surg. 2017; 82: 927-932Crossref PubMed Scopus (11) Google Scholar, 3Stewart K. Urschel J. Nakai S. Gelfand E. Hamilton S. Pulmonary resection for lung trauma.Ann Thorac Surg. 1997; 63: 1587-1588Abstract Full Text Full Text PDF PubMed Scopus (56) Google Scholar The optimal management for posttraumatic pneumonectomy is not well delineated, given the uncommon circumstances.4Martin M. McDonald J. Mullenix P. Steele S. Demetriades D. Operative management and outcomes of traumatic lung resection.J Am Coll Surg. 2006; 203: 336-344Abstract Full Text Full Text PDF PubMed Scopus (34) Google Scholar,5Huh J. Wall M. Estrera A. Solero E. Mattox K. Surgical management of traumatic pulmonary injury.Am J Surg. 2003; 186: 620-624Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar This case had added complexity with involvement of the complex tracheal reconstruction and introduction of contaminated soil into the mediastinum and pleural space due to the traumatic nature of the injury. In the setting of a pneumonectomy, a contaminated pleural space, in and of itself, is a known deadly complication, with mortality rates ranging from 25% to 50%.6Wong P. Goldstraw P. Post-pneumonectomy empyema.Eur J Cardiothorac Surg. 1994; 8: 345-349Crossref PubMed Scopus (30) Google Scholar, 7Ng C. Wan S. Lee T. Wan I. Arifi A. Yim A. Post-pneumonectomy empyema: current management strategies.ANZ J Surg. 2005; 75: 597-602Crossref PubMed Scopus (19) Google Scholar, 8Clark J.M. Cooke T. Brown L.M. Management of complications after lung resection: prolonged air leak and bronchopleural fistula.Thorac Surg Clin. 2020; 30: 347-358Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar Serial washouts and packing with iodinated gauze have been described for management of non–trauma-related early and late postpneumonectomy empyema.9Schneiter D. Cassina P. Korom S. Inci I. Al-Abdullatief M. Dutly A. et al.Accelerated treatment for early and late postpneumonectomy empyema.Ann Thorac Surg. 2001; 72: 1668-1672Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar,10Schneiter D. Grodzki T. Lardinois D. Kestenholz P. Wojcik J. Kubisa B. et al.Accelerated treatment of postpneumonectomy empyema: a binational long-term study.J Thorac Cardiovasc Surg. 2008; 136: 179-185Abstract Full Text Full Text PDF PubMed Scopus (62) Google Scholar A contaminated pleural space in an already highly fatal situation with multiorgan trauma secondary to a motor vehicle crash (MVC) elevates the complexity of the situation. The ability to control a traumatically contaminated space allows for ongoing trauma care including patient mobilization to aid recovery.Pulmonary contusions and acute respiratory distress syndrome (ARDS) are well-known problems following an MVC.11Cohn S.M. Dubose J.J. Pulmonary contusion: an update on recent advances in clinical management.World J Surg. 2010; 34: 1959-1970Crossref PubMed Scopus (103) Google Scholar, 12Sutyak J.P. Wohltmann C.D. Larson J. Pulmonary contusions and critical care management in thoracic trauma.Thorac Surg Clin. 2007; 17: 11-23Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar, 13Daurat A. Millet I. Roustan J.P. Maury C. Taourel P. Jaber S. et al.Thoracic Trauma Severity score on admission allows to determine the risk of delayed ARDS in trauma patients with pulmonary contusion.Injury. 2016; 47: 147-153Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar However, after an emergent pneumonectomy, pulmonary contusions and ARDS of the remaining lung can be disastrous, where ARDS after pneumonectomy carries a mortality rate of 47% to 56%.14Peretti M. Hervochon R. Loi M. Blanc K. Roche N. Alifano M. Predictors of post-pneumonectomy respiratory failure and ARDS: usefulness of normalized pulmonary artery diameter.Intensive Care Med. 2018; 44: 1357-1359Crossref PubMed Scopus (10) Google Scholar, 15Blanc K. Zaimi R. Dechartres A. Lefebvre A. Janet-Vandroux A. Hamelin-Canny E. et al.Early acute respiratory distress syndrome after pneumonectomy: presentation, management, and short-and long-term outcomes.J Thorac Cardiovasc Surg. 2018; 156: 1706-1714Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar, 16Blanc K. Dechartres A. Zaimi R. Lefebvre A. Janet-Vendroux A. Fournel L. et al.Patients experiencing early acute respiratory failure have high postoperative mortality after pneumonectomy.J Thorac Cardiovasc Surg. 2018; 156: 2368-2376Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar Venovenous extracorporeal membrane oxygenation (V-V ECMO) has been used in the settings of ARDS,17Combes A. Hajaga D. Capellier G. Demoule A. Lavoue S. Guervilly C. et al.Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome.N Engl J Med. 2018; 378: 1965-1975Crossref PubMed Scopus (1000) Google Scholar,18Brodie D. Bacchetta M. Extracorporeal membrane oxygenation for ARDS in Adults.N Engl J Med. 2011; 365: 1905-1914Crossref PubMed Scopus (561) Google Scholar traumatic lung injury,19Robba C. Ortu A. Bilotta F. Lombardo A. Sekhon M. Gallo F. et al.Extracorporeal membrane oxygenation for adult respiratory distress syndrome in trauma patients: a case series and systematic literature review.J Trauma Acute Care Surg. 2017; 82: 165-173Crossref PubMed Scopus (36) Google Scholar,20Guirand D. Okoye O. Schmidt B. Mansfield N. Aden J. Martin R. et al.Venovenous extracorporeal life support improves survival in adult trauma patients with acute hypoxemic respiratory failure: a multicenter retrospective cohort study.J Trauma Acute Care Surg. 2014; 76: 1275-1281Crossref PubMed Scopus (70) Google Scholar and complex tracheal reconstruction21Qiu Y. Chen Q. Wu W. Zhang S. Tang M. Chen Y. et al.Extracorporeal membrane oxygenation (ECMO)-assisted intratracheal tumor resection and carina reconstruction: a safer and more effective technique for resection and reconstruction.Thorac Cancer. 2019; 10: 1297-1302Crossref PubMed Scopus (8) Google Scholar,22Lei J. Su K. Li X. Zhou Y. Han Y. Juang L. et al.ECMO-assisted carinal resection and reconstruction after left pneumonectomy.J Cardiothorac Surg. 2010; 5: 89Crossref PubMed Scopus (24) Google Scholar as a bridge to recovery; this case involved all 3.Case DescriptionUniversity of Florida, UF Health Shands, and patient written informed consent and authorization to use and disclose deidentified health information for publication and educational purposes was obtained (institutional review board #202000163, approval date February 19, 2020). The patient was a 14-year-old, restrained driver of a single-car motor vehicle crash into a horse farm fence at highway speed resulting in penetrating thoracic trauma with impalement of a wooden fence board via a right parasternal entry site and right paraspinal exit site (Figure 1). The patient had a prolonged extrication time over 1 hour due to her impalement injury and arrived to the emergency department with the wooden fence through-and-through her chest such that she could not lay flat, a Glasgow Coma Scale of 14, blood pressure 150/110 mm Hg, heart rate 142, temperature 33.8 °C, and oxygen saturation of 88% on a nonrebreather mask. She was subsequently intubated and resuscitated in the trauma bay, which improved her oxygen saturations and tachycardia. She was then brought emergently to the operating room for the traumatic thoracic injury. She did not undergo any imaging or chest tube placement in the emergency department for fear of delaying definitive care and/or disrupting the injuries already present.Figure 1A, Image at the scene of the car shown with the fence through the windshield. B, Graphical depiction of injury with the anterior red highlighted area on the skin depicting the right parasternal entry site and posterior red highlighted area depicting the right paraspinal exit site. The impalement was just lateral to the heart.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Once in the operation room (Video 1), the patient was positioned with a bump on the right side due to an inability to lay flat secondary to the fence protruding through her back wound. The fence piece was from a horse farm, and inspection of the wood revealed animal hair, soil, and mold (Figure 2, A). In addition, her shirt had to be cut around the fence, and part of her shirt could also be seen passing through her chest and exiting the back. A preoperative plan entailed a right thoracotomy with the option for a clamshell extension, if needed. Additional preparation involved a left groin cutdown for emergent access to the femoral vessels in the case that cardiopulmonary bypass was required.Figure 2A, Traumatic impalement injury with right parasternal entry site and right paraspinal exit site. B, Surgical image status post right thoracotomy and right middle and lower lobectomy, before removal of the foreign body. C, Surgical image showing cross-table ventilation for complex tracheoplasty.View Large Image Figure ViewerDownload Hi-res image Download (PPT)After right anterolateral thoracotomy, a large volume air leak was noted, but no active bleeding. The anesthesiologists completed a flexible fiberoptic bronchoscopy and it appeared the right mainstem was compressed and unable to be visualized, and subsequently the endotracheal tube was advanced into the left mainstem in preparation for further surgical exploration. There were small fragments of the wooden shards from the fence freely inside her chest cavity, as well as fragments of cloth from the patient's shirt. The pericardium was noted to be torn by the impalement, but the heart was without injury. The pericardium was further opened to have access to the intrapericardial pulmonary artery and veins for vascular control. Right middle and lower lobectomies were performed promptly, as they both appeared to have been transected away from the hilum by the wooden piece and were no longer attached secondary to the traumatic injury. We then noted that the right upper lobe was severely congested. Before removal of the foreign body, vascular clamps and staplers were made available. Cardiac anesthesia, perfusionist, trauma surgeon, cardiac surgeon, thoracic surgeon, cardiothoracic surgery scrub technicians, and circulators coordinated the removal of the foreign body (Figure 2, B). The video accompanying this article shows the active removal of the fence and additional intraoperative images.After removal of the foreign body, the right superior pulmonary vein was noted to have already been transected and sealed by the fence board, which is why it was so congested in appearance. As the right upper lobe appeared infarcted, an expeditious right upper lobectomy was then performed. Now with full visualization, the source of the air leak could be identified. The right main stem bronchus was three-fourths detached from the carina with an associated inferior carinal injury. The residual right mainstem was debrided to healthy tissue while cross field ventilation was used (Figure 2, C). The right mainstem remnant was used a cartilaginous flap onto the carinal injury and sutured in placed. An intercostal muscle flap was placed to protect the complex tracheal reconstruction.At the conclusion of the operation, the patient was placed on V-V ECMO for a multitude of reasons. First, the patient was status post-MVC with prolonged extrication who required large-volume resuscitation with crystalloid and 4 units of packed red bloods cells, as well as having severe pulmonary contusions of the remaining lung. These combined contributed to postoperative hypoxia. Second, for protection of the complex tracheal reconstruction, it was felt that low positive end-expiratory pressure would be ideal for healing of the tracheal wound. She underwent right internal jugular vein and right femoral venous cannulation with an 18-Fr cannula in the internal jugular vein and 25-Fr cannula in the groin. At our institution, we preferentially use 2 separate venous cannulas, as we have anecdotally had had some trouble with flows using a single-catheter VV-ECMO cannula. Her postoperative radiograph is seen in Figure 3, A. This image shows a closed chest with gauze packing in right chest space, chest tube in place, V-V ECMO cannulas in the superior vena cava and inferior vena cava, and a left lung with severe pulmonary contusions and volume overload. We also considered placing the patient on venoarterial ECMO (V-A ECMO), assuming that she might experience postpneumonectomy right heart strain. Due to relative stability of her hemodynamics postoperatively, we elected to pursue V-V ECMO to decrease the need for anticoagulation that is needed for V-A ECMO in this trauma patient.Figure 3A, Postoperative image showing povidone–iodine-soaked gauze packing in right chest space with chest tube in place within the sponges and closed chest with staples. In addition, venovenous extracorporeal membrane oxygenation cannulas can be seen in the superior vena cava and inferior vena cava. The left lung is noted to have severe pulmonary contusions and volume overload after large volume resuscitation and postpneumonectomy. B, Follow-up chest radiograph image as an outpatient showing normalized left lung and right pneumonectomy site that is appropriately fluid-filled.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Not surprisingly, transthoracic echocardiogram on postoperative day 1 revealed a severely dilated right ventricle with depressed right ventricular systolic function. The patient was extubated on postinjury day 3 and ambulated daily in the intensive care unit with support from the intensive care unit providers, nurses, and physical/occupational therapy. By postinjury day 6, her echocardiogram exhibited some recovery with now a moderately dilated right ventricle and improved systolic function while on a milrinone drip. Her right ventricular size and function had normalized on the echocardiogram obtained on postinjury day 16 on no support. Ultimately, she was decannulated from ECMO 25 days after her injury. Figure 3, B, shows her chest radiograph after discharge.The impalement from the fence not only caused significant direct injury to the patient's lung, but additionally it introduced gross contamination into the pleural space. The dirty fence went through-and-through the patient's body, and pieces of her shirt were also noted inside the chest cavity as well. The fence was from a horse farm, and upon direct inspection of the wood was noted animal hair, soil, and mold. Small shards of the fence were inside the chest cavity as well. For management of her severely contaminated pleural space, the patient required 6 washouts and debridements with iodine–povidone- soaked gauze packs, and broad-spectrum antibiotic and fungal coverage. This approach has been described by Schneiter and colleagues9Schneiter D. Cassina P. Korom S. Inci I. Al-Abdullatief M. Dutly A. et al.Accelerated treatment for early and late postpneumonectomy empyema.Ann Thorac Surg. 2001; 72: 1668-1672Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar,10Schneiter D. Grodzki T. Lardinois D. Kestenholz P. Wojcik J. Kubisa B. et al.Accelerated treatment of postpneumonectomy empyema: a binational long-term study.J Thorac Cardiovasc Surg. 2008; 136: 179-185Abstract Full Text Full Text PDF PubMed Scopus (62) Google Scholar for postpneumonectomy empyema, and was adapted for use in this traumatic setting. The patient underwent reopening of the closed thoracotomy incision, debridement of the pleural cavity, irrigation, and packing with diluted povidone–iodine:normal saline (1:10)-soaked gauze sponges. The chest is then fully closed, and the pleural tube is then placed on suction. The pleural tube is surrounded by the gauze, which applies a negative pressure wound therapy to the pleural space via suction on the gauze (Figure 3, A). This process is repeated every 48 to 72 hours until the chest cavity is macroscopically clean. By macroscopically clean, in our case meant there were no longer deposits of gelatinous or fibrinous material on the gauze, foul smell, or green coloration to the sponges as there had been in previous washouts.Finally, the chest cavity was obliterated with antibiotic solution and the thoracotomy incision definitively closed. The final closing of her chest was accomplished on postinjury day 20. She was maintained on V-V ECMO throughout the process of the serial washouts to preserve the tracheal repair even during intubation for the debridements. She was discharged postinjury day 63 and made a full recovery. The patient is now 3 years status post-MVC and pneumonectomy doing well as an outpatient. She was positive for the severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019) in December 2020, received remdesivir, and made a full uneventful recovery.DiscussionPosttraumatic pneumonectomy is a rare event with potential for high morbidity and mortality. Pneumonectomy alone carries a high risk, but the additive risk of injuries from a high-speed MVC elevates the hazards for recovery. Although lung-sparing techniques are associated with improved outcomes compared with anatomic resection for severe lung injuries,23Cothren C. Moor E.E. Biffl W.L. Franciose R.J. Offner P.J. Burch J.M. Lung-sparing techniques are associated with improved outcome compared with anatomic resection for severe Lung Injuries.J Trauma. 2002; 53: 483-487Crossref PubMed Scopus (55) Google Scholar this case required an emergent completion pneumonectomy with carinal reconstruction due to the location of the injury. The addition of the complex tracheal intervention and the grossly contaminated pleural space creates a potentially lethal situation. We had placed the patient on V-V ECMO after the completion of the operation, but looking back, could have placed the patient on V-V ECMO before tracheal reconstruction. In addition, her eventual normalization of right heart function confirmed our decision to not use V-A ECMO, although it was certainly considered at the time.Serial washouts and packing with iodine solution of the pleural space until resolution of gross contamination has been previously described for management of non–trauma-related early and late postpneumonectomy empyema.9Schneiter D. Cassina P. Korom S. Inci I. Al-Abdullatief M. Dutly A. et al.Accelerated treatment for early and late postpneumonectomy empyema.Ann Thorac Surg. 2001; 72: 1668-1672Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar,10Schneiter D. Grodzki T. Lardinois D. Kestenholz P. Wojcik J. Kubisa B. et al.Accelerated treatment of postpneumonectomy empyema: a binational long-term study.J Thorac Cardiovasc Surg. 2008; 136: 179-185Abstract Full Text Full Text PDF PubMed Scopus (62) Google Scholar The ability to control a traumatically contaminated space in this manner allowed for furthering of the ongoing trauma. The alternative would have been open packing and long-term wound-healing issues. The ability to temporarily close the pleural space after each wash out allowed for physical therapy and occupational therapy to advance the patient's recovery.Furthermore, use of V-V ECMO for the enhancement in the patient's recovery was paramount. V-V ECMO allowed for early extubation and offered protection of the remaining lung and tracheal reconstruction by minimizing the positive pressure ventilation. While cannulated on ECMO, the critical care team, nursing, and therapy continued to mobilize the patient and walk the intensive care unit hallways. Ambulation in an ECMO patient takes extraordinary support and buy-in from all parties involved. This complex case highlights the importance of teamwork and highly specialized, advanced, multidisciplinary care. Overall, this dramatic case demonstrates the valuable use of V-V ECMO support after traumatic injury and complex tracheal reconstruction, as well as the confirms that serial washouts with iodine-soaked gauze for a contaminated pleural space can be an effective treatment strategy. Posttraumatic pneumonectomy is a highly morbid and lethal event. Postoperative use of venovenous ECMO and serial washouts for a contaminated pleural space is an effective treatment strategy. Posttraumatic pneumonectomy is a highly morbid and lethal event. Postoperative use of venovenous ECMO and serial washouts for a contaminated pleural space is an effective treatment strategy. See Commentary on page 280. See Commentary on page 280. Posttraumatic pneumonectomy is a rare event that carries extremely high morbidity and mortality.1Homo R. Grigorian A. Lekawa M. Dolich M. Kuza C. Doben A. et al.Outcomes after pneumonectomy versus limited lung resection in adults with traumatic lung injury.Updates Surg. 2020; 72: 547-553Crossref PubMed Scopus (3) Google Scholar, 2Matsushima K. Aiolfi A. Park C. Rosen D. Strumwasser A. Benjamin E. et al.Surgical outcomes after trauma pneumonectomy.J Trauma Acute Care Surg. 2017; 82: 927-932Crossref PubMed Scopus (11) Google Scholar, 3Stewart K. Urschel J. Nakai S. Gelfand E. Hamilton S. Pulmonary resection for lung trauma.Ann Thorac Surg. 1997; 63: 1587-1588Abstract Full Text Full Text PDF PubMed Scopus (56) Google Scholar The optimal management for posttraumatic pneumonectomy is not well delineated, given the uncommon circumstances.4Martin M. McDonald J. Mullenix P. Steele S. Demetriades D. Operative management and outcomes of traumatic lung resection.J Am Coll Surg. 2006; 203: 336-344Abstract Full Text Full Text PDF PubMed Scopus (34) Google Scholar,5Huh J. Wall M. Estrera A. Solero E. Mattox K. Surgical management of traumatic pulmonary injury.Am J Surg. 2003; 186: 620-624Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar This case had added complexity with involvement of the complex tracheal reconstruction and introduction of contaminated soil into the mediastinum and pleural space due to the traumatic nature of the injury. In the setting of a pneumonectomy, a contaminated pleural space, in and of itself, is a known deadly complication, with mortality rates ranging from 25% to 50%.6Wong P. Goldstraw P. Post-pneumonectomy empyema.Eur J Cardiothorac Surg. 1994; 8: 345-349Crossref PubMed Scopus (30) Google Scholar, 7Ng C. Wan S. Lee T. Wan I. Arifi A. Yim A. Post-pneumonectomy empyema: current management strategies.ANZ J Surg. 2005; 75: 597-602Crossref PubMed Scopus (19) Google Scholar, 8Clark J.M. Cooke T. Brown L.M. Management of complications after lung resection: prolonged air leak and bronchopleural fistula.Thorac Surg Clin. 2020; 30: 347-358Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar Serial washouts and packing with iodinated gauze have been described for management of non–trauma-related early and late postpneumonectomy empyema.9Schneiter D. Cassina P. Korom S. Inci I. Al-Abdullatief M. Dutly A. et al.Accelerated treatment for early and late postpneumonectomy empyema.Ann Thorac Surg. 2001; 72: 1668-1672Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar,10Schneiter D. Grodzki T. Lardinois D. Kestenholz P. Wojcik J. Kubisa B. et al.Accelerated treatment of postpneumonectomy empyema: a binational long-term study.J Thorac Cardiovasc Surg. 2008; 136: 179-185Abstract Full Text Full Text PDF PubMed Scopus (62) Google Scholar A contaminated pleural space in an already highly fatal situation with multiorgan trauma secondary to a motor vehicle crash (MVC) elevates the complexity of the situation. The ability to control a traumatically contaminated space allows for ongoing trauma care including patient mobilization to aid recovery. Pulmonary contusions and acute respiratory distress syndrome (ARDS) are well-known problems following an MVC.11Cohn S.M. Dubose J.J. Pulmonary contusion: an update on recent advances in clinical management.World J Surg. 2010; 34: 1959-1970Crossref PubMed Scopus (103) Google Scholar, 12Sutyak J.P. Wohltmann C.D. Larson J. Pulmonary contusions and critical care management in thoracic trauma.Thorac Surg Clin. 2007; 17: 11-23Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar, 13Daurat A. Millet I. Roustan J.P. Maury C. Taourel P. Jaber S. et al.Thoracic Trauma Severity score on admission allows to determine the risk of delayed ARDS in trauma patients with pulmonary contusion.Injury. 2016; 47: 147-153Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar However, after an emergent pneumonectomy, pulmonary contusions and ARDS of the remaining lung can be disastrous, where ARDS after pneumonectomy carries a mortality rate of 47% to 56%.14Peretti M. Hervochon R. Loi M. Blanc K. Roche N. Alifano M. Predictors of post-pneumonectomy respiratory failure and ARDS: usefulness of normalized pulmonary artery diameter.Intensive Care Med. 2018; 44: 1357-1359Crossref PubMed Scopus (10) Google Scholar, 15Blanc K. Zaimi R. Dechartres A. Lefebvre A. Janet-Vandroux A. 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The patient was a 14-year-old, restrained driver of a single-car motor vehicle crash into a horse farm fence at highway speed resulting in penetrating thoracic trauma with impalement of a wooden fence board via a right parasternal entry site and right paraspinal exit site (Figure 1). The patient had a prolonged extrication time over 1 hour due to her impalement injury and arrived to the emergency department with the wooden fence through-and-through her chest such that she could not lay flat, a Glasgow Coma Scale of 14, blood pressure 150/110 mm Hg, heart rate 142, temperature 33.8 °C, and oxygen saturation of 88% on a nonrebreather mask. She was subsequently intubated and resuscitated in the trauma bay, which improved her oxygen saturations and tachycardia. She was then brought emergently to the operating room for the traumatic thoracic injury. She did not undergo any imaging or chest tube placement in the emergency department for fear of delaying definitive care and/or disrupting the injuries already present.Once in the operation room (Video 1), the patient was positioned with a bump on the right side due to an inability to lay flat secondary to the fence protruding through her back wound. The fence piece was from a horse farm, and in

How to deliver best care in various clinical settings remains a vexing problem. All pertinent healthcare-related questions have not, cannot, and will not be addressable with costly time- and resource-consuming controlled clinical trials. At present, evidence-based guidelines can address only a small fraction of the types of care that clinicians deliver. Furthermore, underserved areas rarely can access state-of-the-art evidence-based guidelines in real-time, and often lack the wherewithal to implement advanced guidelines. Care providers in such settings frequently do not have sufficient training to undertake advanced guideline implementation. Nevertheless, in advanced modern healthcare delivery environments, use of eActions (validated clinical decision support systems) could help overcome the cognitive limitations of overburdened clinicians. Widespread use of eActions will require surmounting current healthcare technical and cultural barriers and installing clinical evidence/data curation systems. The authors expect that increased numbers of evidence-based guidelines will result from future comparative effectiveness clinical research carried out during routine healthcare delivery within learning healthcare systems.

Multiple organ failure (MOF) emerged over four decades ago with the advent of intensive care units (ICUs). Over the ensuing decades with ongoing fundamental advances in trauma and ICU care, this syndrome has evolved from being a fulminant progression of organ failure leading to early ICU death to now being a lingering chronic critical illness (CCI) leading to frailty, long-term disabilities, and indolent post-ICU death. In 2012, the term Persistent Inflammation, Immunosuppression, and Catabolism Syndrome (PICS) was coined to describe this new CCI MOF phenotype and to provide a mechanistic framework in which to study CCI in surgical ICU patients. The chapter will discuss the evolving epidemiology and pathobiology of MOF through a series of conceptual paradigms including (a) septic auto-cannibalism, (b) sepsis syndrome, (c) abdominal compartment syndrome, and (d) the SIRS/CARS paradigm. It will then describe how modern trauma and ICU care have largely eliminated in-hospital MOF deaths, but have unfortunately created an epidemic of PICS-CCI survivors who have dismal long-term outcomes. It will conclude by discussing ongoing research efforts over the past 5 years to prospectively study the long-term outcome of PICS-CCI survivors and obtain serial biomarkers to gain insight into its underlying pathobiology.

BACKGROUND The American Society for Parenteral and Enteral Nutrition (ASPEN)/ Society of Critical Care Medicine and the European Society for Clinical Nutrition and Metabolism guidelines recognize that critically ill patients receiving stable, low doses of vasopressors have experienced the advantages of early initiation of enteral nutrition (EN). However, clinical questions remained unanswered including vasopressor combinations associated with complications, the advent of other therapies during hypotensive states, as well as the volume and content of EN that might contribute to the development of a nonocclusive mesenteric ischemia (NOMI). PRESENTATION A 68-year old male with a history of hypertension, hyperlipidemia, atrial fibrillation, coronary artery disease with two-vessel bypass grafting, and peripheral vascular disease underwent subtotal excision of an infected right axillofemoral-femoral bypass graft. Postoperatively, EN was held because of hemodynamic instability and postsurgical complications. A fiber-free, high-protein, and low-residue formula was started at 10 ml/h while the patient was receiving stable doses of midodrine, norepinephrine, and vasopressin. Despite advancement of tube-feed rates to goal, nasogastric output never exceeded 300 ml. Computerized tomography of the abdomen showed diffuse bowel distention with pneumatosis, concerning for bowel ischemia. No surgical interventions were pursued, and the patient died. CONCLUSIONS Our patient developed NOMI postoperatively while receiving EN. Further studies addressing EN route, trophic vs full EN, recommended formula, the safety of vasoactive agents, the addition of fiber to EN, and continuous venovenous hemodiafiltration in relation to NOMI are needed, as there continues to be clinical controversy regarding these topics.

Objective: To characterize endothelial function, inflammation, and immunosuppression in surgical patients with distinct clinical trajectories of AKI and to determine the impact of persistent kidney injury and renal non-recovery on clinical outcomes, resource utilization, and long-term disability and survival. Summary of Background Data: AKI is associated with increased healthcare costs and mortality. Trajectories that account for duration and recovery of AKI have not been described for sepsis patients, who are uniquely vulnerable to renal dysfunction. Methods: This prospective observational study included 239 sepsis patients admitted and enrolled between January 2015 and July 2017. Kidney Disease: Improving Global Outcomes (KDIGO) and Acute Disease Quality Initiative (ADQI) criteria were used to classify subjects as having no AKI, rapidly reversed AKI, persistent AKI with renal recovery, or persistent AKI without renal recovery. Serial biomarker profiles, clinical outcomes, resource utilization, and long-term physical performance status and survival were compared among AKI trajectories. Results: Sixty-two percent of the study population developed AKI. Only one-third of AKI episodes rapidly reversed within 48 hours; the remaining had persistent AKI, among which 57% did not have renal recovery by discharge. One-year survival and proportion of subjects fully active 1 year after sepsis was lowest among patients with persistent AKI compared with other groups. Long-term mortality hazard rates were 5-fold higher for persistent AKI without renal recovery compared with no AKI. Conclusions: Among critically ill surgical sepsis patients, persistent AKI and the absence of renal recovery are associated with distinct early and sustained immunologic and endothelial biomarker signatures and decreased long-term physical function and survival.

Improved management of severe sepsis has been one of the major health care accomplishments of the last two decades. Due to enhanced recognition and improved management of severe sepsis, in-hospital mortality has been reduced by up to 40%. With that good news, a new syndrome has unfortunately replaced in-hospital multi-organ failure and death. This syndrome of chronic critical illness (CCI) includes sepsis patients who survive the early “cytokine or genomic storm,” but fail to fully recover, and progress into a persistent state of manageable organ injury requiring prolonged intensive care. These patients are commonly discharged to long-term care facilities where sepsis recidivism is high. As many as 33% of sepsis survivors develop CCI. CCI is the result, at least in part, of a maladaptive host response to chronic pattern-recognition receptor (PRR)-mediated processes. This maladaptive response results in dysregulated myelopoiesis, chronic inflammation, T-cell atrophy, T-cell exhaustion, and the expansion of suppressor cell functions. We have defined this panoply of host responses as a persistent inflammatory, immune suppressive and protein catabolic syndrome (PICS). Why is this important? We propose that PICS in survivors of critical illness is its own common, unique immunological endotype driven by the constant release of organ injury-associated, endogenous alarmins, and microbial products from secondary infections. While this syndrome can develop as a result of a diverse set of pathologies, it represents a shared outcome with a unique underlying pathobiological mechanism. Despite being a common outcome, there are no therapeutic interventions other than supportive therapies for this common disorder. Only through an improved understanding of the immunological endotype of PICS can rational therapeutic interventions be designed.

Objective Approximately one-third of sepsis patients experience poor outcomes including chronic critical illness (CCI, intensive care unit (ICU) stay > 14 days) or early death (in-hospital death within 14 days). We sought to characterize lipoprotein predictive ability for poor outcomes and contribution to sepsis heterogeneity. Design Prospective cohort study with independent replication cohort. Setting Emergency department and surgical ICU at two hospitals. Patients Sepsis patients presenting within 24 h. Methods Measures included cholesterol levels (total cholesterol, high density lipoprotein cholesterol [HDL-C], low density lipoprotein cholesterol [LDL-C]), triglycerides, paraoxonase-1 (PON-1), and apolipoprotein A-I (Apo A-I) in the first 24 h. Inflammatory and endothelial markers, and sequential organ failure assessment (SOFA) scores were also measured. LASSO selection assessed predictive ability for outcomes. Unsupervised clustering was used to investigate the contribution of lipid variation to sepsis heterogeneity. Measurements and main results 172 patients were enrolled. Most (~ 67%, 114/172) rapidly recovered, while ~ 23% (41/172) developed CCI, and ~ 10% (17/172) had early death. ApoA-I, LDL-C, mechanical ventilation, vasopressor use, and Charlson Comorbidity Score were significant predictors of CCI/early death in LASSO models. Unsupervised clustering yielded two discernible phenotypes. The Hypolipoprotein phenotype was characterized by lower lipoprotein levels, increased endothelial dysfunction (ICAM-1), higher SOFA scores, and worse clinical outcomes (45% rapid recovery, 40% CCI, 16% early death; 28-day mortality, 21%). The Normolipoprotein cluster patients had higher cholesterol levels, less endothelial dysfunction, lower SOFA scores and better outcomes (79% rapid recovery, 15% CCI, 6% early death; 28-day mortality, 15%). Phenotypes were validated in an independent replication cohort (N = 86) with greater sepsis severity, which similarly demonstrated lower HDL-C, ApoA-I, and higher ICAM-1 in the Hypolipoprotein cluster and worse outcomes (46% rapid recovery, 23% CCI, 31% early death; 28-day mortality, 42%). Normolipoprotein patients in the replication cohort had better outcomes (55% rapid recovery, 32% CCI, 13% early death; 28-day mortality, 28%) Top features for cluster discrimination were HDL-C, ApoA-I, total SOFA score, total cholesterol level, and ICAM-1. Conclusions Lipoproteins predicted poor sepsis outcomes. A Hypolipoprotein sepsis phenotype was identified and characterized by lower lipoprotein levels, increased endothelial dysfunction (ICAM-1) and organ failure, and worse clinical outcomes.

Background With the successful implementation of the Surviving Sepsis Campaign guidelines, post-sepsis in-hospital mortality to sepsis continues to decrease. Those who acutely survive surgical sepsis will either rapidly recover or develop a chronic critical illness (CCI). CCI is associated with adverse long-term outcomes and 1-year mortality. Although the pathobiology of CCI remains undefined, emerging evidence suggests a post-sepsis state of pathologic myeloid activation, inducing suboptimal lymphopoiesis and erythropoiesis, as well as downstream leukocyte dysfunction. Our goal was to use single-cell RNA sequencing (scRNA-seq) to perform a detailed transcriptomic analysis of lymphoid-derived leukocytes to better understand the pathology of late sepsis. Methods A mixture of whole blood myeloid-enriched and Ficoll-enriched peripheral blood mononuclear cells from four late septic patients (post-sepsis day 14-21) and five healthy subjects underwent Cellular Indexing of Transcriptomes and Epitopes by Sequencing (CITE-seq). Results We identified unique transcriptomic patterns for multiple circulating immune cell subtypes, including B- and CD4(+), CD8(+), activated CD4(+) and activated CD8(+) T-lymphocytes, as well as natural killer (NK), NKT, and plasmacytoid dendritic cells in late sepsis patients. Analysis demonstrated that the circulating lymphoid cells maintained a transcriptome reflecting immunosuppression and low-grade inflammation. We also identified transcriptomic differences between patients with bacterial versus fungal sepsis, such as greater expression of cytotoxic genes among CD8(+) T-lymphocytes in late bacterial sepsis. Conclusion Circulating non-myeloid cells display a unique transcriptomic pattern late after sepsis. Non-myeloid leukocytes in particular reveal a host endotype of inflammation, immunosuppression, and dysfunction, suggesting a role for precision medicine-guided immunomodulatory therapy.

BACKGROUND:After severe trauma, the older host experiences more dysfunctional hematopoiesis of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs), and dysfunctional differentiation of circulating myeloid cells into effective innate immune cells. Our main objective was to compare BM HSPC microRNA (miR) responses of old and young mice in a clinically relevant model of severe trauma and shock.METHODS:C57BL/6 adult male mice aged 8 to 12 weeks (young) and 18 to 24 months (old) underwent multiple injuries and hemorrhagic shock (polytrauma [PT]) that engenders the equivalent of major trauma (Injury Severity Score, >15). Pseudomonas pneumonia (PNA) was induced in some young and old adult mice 24 hours after PT. MicroRNA expression patterns were determined from lineage-negative enriched BM HSPCs isolated from PT and PT-PNA mice at 24 and 48 hours postinjury, respectively. Genome-wide expression and pathway analyses were also performed on bronchoalveolar lavage (BAL) leukocytes from both mouse cohorts.RESULTS:MicroRNA expression significantly differed among all experimental conditions (p < 0.05), except for old-naive versus old-injured (PT or PT-PNA) mice, suggesting an inability of old mice to mount a robust early miR response to severe shock and injury. In addition, young adult mice had significantly more leukocytes obtained from their BAL, and there were greater numbers of polymorphonuclear cells compared with old mice (59.8% vs. 2.2%, p = 0.0069). Despite increased gene expression changes, BAL leukocytes from old mice demonstrated a more dysfunctional transcriptomic response to PT-PNA than young adult murine BAL leukocytes, as reflected in predicted upstream functional pathway analysis.CONCLUSION:The miR expression pattern in BM HSPCs after PT (+/-PNA) is dissimilar in old versus young adult mice. In the acute postinjury phase, old adult mice are unable to mount a robust miR HSPC response. Hematopoietic stem and progenitor cell miR expression in old PT mice reflects a diminished functional status and a blunted capacity for terminal differentiation of myeloid cells.

The American and European guidelines recommend measuring resting energy expenditure (REE) using indirect calorimetry (IC). Predictive equations (PEs) are used to estimate REE, but there is limited evidence for their use in critically ill patients. The aim of this study is to evaluate the degree of agreement and accuracy between IC-measured REE (REE-IC) and 10 different PEs in mechanically ventilated critically ill patients with surgical trauma who met their estimated energy requirement.REE-IC was retrospectively compared with REE-PE by 10 PEs. The degree of agreement between REE-PE and REE-IC was analyzed by the Bland-Altman test (BAt) and the concordance correlation coefficient (CCC). The accuracy was calculated by the percentage of patients whose REE-PE values differ by up to ±10% in relation to REE-IC. All analyses were stratified by gender and body mass index (BMI; <25 vs ≥25).We analyzed 104 patients and the closest estimate to REE-IC was the modified Harris-Benedict equation (mHB) by the BAt with a mean difference of 49.2 overall (61.6 for males, 28.5 for females, 67.5 for BMI <25, and 42.5 for BMI ≥25). The overall CCC between the REE-IC and mHB was 0.652 (0.560 for males, 0.496 for females, 0.570 for BMI <25, and 0.598 for BMI ≥25). The mHB equation was the most accurate with an overall accuracy of 44.2%.The effectiveness of PEs for estimating the REE of mechanically ventilated surgical-trauma critically ill patients is limited. [Correction added on 17 February 2022, after first online publication: The word "with" was deleted before "is limited" in the preceding sentence.] Nonetheless, of the 10 equations examined, the closest to REE-IC was the mHB equation.

AbstractBackgroundSarcopenia is a known risk factor for poor outcomes across many chronic diseases. The impact on outcomes of both pre‐existing sarcopenia and acute muscle wasting (AMW) in acute critical illness caused by sepsis remain unclear.MethodsWe conducted a prospective longitudinal cohort study of critically ill patients with intra‐abdominal sepsis utilizing abdominal computed tomography at sepsis onset to determine baseline skeletal muscle index (SMI). Biomarkers of inflammation and catabolism were measured through 28 days while hospitalized. We performed follow‐up evaluations of strength and physical function at 3, 6, and 12 months, with interval CT analyses at 3 and 12 months to evaluate changes in muscle mass. Measured clinical outcomes included development of chronic critical illness (≥14 days in intensive care with persistent organ dysfunction), long‐term functional status, and 1 year mortality.ResultsAmong 47 sepsis patients enrolled (mean age 53 ± 14 years), half (n = 23; 49%) were sarcopenic at baseline. Overall, sepsis patients exhibited acute and persistent muscle wasting with an average 8% decrease in SMI from baseline at 3 months (P = 0.0008). Sarcopenic (SAR) and non‐sarcopenic (NSAR) groups were similar in regards to age and comorbidity burden. SAR patients had greater acute physiologic derangement (APACHE II, 18 vs. 12.5), higher incidence of multiple organ failure (57% vs. 17%), longer hospital (21 vs. 12 days) and intensive care unit length of stays (13 vs. 4 days), and higher inpatient mortality (17% vs. 0%; all P < 0.05). Pre‐existing SAR was a strong independent predictor of early death or developing chronic critical illness (odds ratio 11.87, 95% confidence interval CI 1.88–74.9; P = 0.009, area under the curve 0.880) and was associated with significantly higher risk of 1‐year mortality (34.9% vs. 4.2%, p = 0.007). Lower baseline SMI was also predictive of poor functional status at 12 months (OR 0.89, 95% confidence interval 0.80–0.99; p = 0.039, area under the curve 0.867). Additionally, SAR patients had AMW with persistent muscle mass loss at 3 months that was associated with decreased health‐related quality of life and SF‐36 physical function domains (P < 0.05). Persistent AMW at 3 months was not predictive of mortality or poor functional status, with return to near‐baseline muscle mass among sepsis survivors by 6 months.ConclusionsCritically ill patients have an acute and persistent loss of muscle mass after intra‐abdominal sepsis, which is associated with decreased health‐related quality of life and physical function at 3 months. However, pre‐existing sarcopenia, rather than persistent acute muscle mass loss at 3 months after sepsis, is independently associated with poor long‐term functional status and increased 1 year mortality.