Psoas Muscle Morphology as a Sarcopenia Marker to Predict Outcomes of Geriatric Trauma Patients: A Systematic Review and Meta-analysis

Objective

To provide pooled evidence on the association between central sarcopenia and risk of mortality and/or complications among geriatric patients with moderate to severe trauma.

Methods

We conducted a systematic search in PubMed, EMBASE, and Scopus databases for relevant observational studies documenting the association of central sarcopenia with the risk of mortality and/or complications in geriatric patients with moderate to severe trauma. The studies reported computerized tomography (CT) based assessments of the psoas muscle cross-sectional area. We used a random effects model for the analysis and reported effect sizes as pooled odds ratios (ORs) or hazards ratios (HRs) along with 95% confidence intervals.

Results

We analyzed data from 13 studies and found an association between the presence of psoas muscle size reduction and the risk of in-hospital mortality (OR, 1.47; 95% CI, 1.13, 1.90). In addition, we found increased risk of mortality within 24 months of follow-up in patients with sarcopenia (HR, 2.40; 95% CI, 1.11-5.17). We found each unit increase in psoas muscle cross-sectional area to be significantly associated with reduced risk of mortality within 24 months of follow-up (HR, .92; 95% CI, .90-.95). Patients with sarcopenia also had an increased risk of complications (OR, 1.69; 95% CI, 1.08-2.63).

Conclusion

Central sarcopenia, assessed using psoas muscle morphology, among geriatric patients with moderate to severe trauma appears to be significantly associated with increased risks of mortality and complications.

Association of longitudinal changes in skeletal muscle mass with prognosis and nutritional intake in acutely hospitalized patients with abdominal trauma: a retrospective observational study

Background

The objective of this study was to explore whether longitudinal changes in skeletal muscle mass, from hospital admission to 3  weeks post-trauma, are associated with poor prognosis and nutritional intake in acutely hospitalized patients with abdominal trauma.

Methods

A single-center retrospective observational review was conducted on 103 patients with abdominal trauma admitted to the Affiliated Jinling Hospital, Medical School of Nanjing University between January 2010 and April 2020. Skeletal muscle mass was assessed by abdominal computed tomography (CT) performed within 14 days before surgery and on post-trauma days 1-3 (week 0), 7-10 (week 1), 14-17 (week 2), and 21-24 (week 3). The skeletal muscle index (SMI) at L3, change in SMI per day (ΔSMI/day), and percent change in SMI per day (ΔSMI/day [%]) were calculated. The receiver-operating characteristic (ROC) curve was used to evaluate the discriminatory performance of ΔSMI/day (%) for mortality. Linear correlation analysis was used to evaluate the associations between ΔSMI/day (%) and daily caloric or protein intake.

Results

Among the included patients, there were 91 males and 12 females (mean age ± standard deviation 43.74 ± 15.53 years). ΔSMI_4-1/d (%) had a ROC-area under the curve of 0.747 (p = 0.048) and a cut-off value of -0.032 for overall mortality. There were significant positive correlations between ΔSMI_4-1/d (%) and daily caloric intake and protein intake (Y = 0.0007501*X - 1.397, R² = 0.282, R = 0.531, p < 0.001; Y = 0.008183*X - 0.9228, R² = 0.194, R = 0.440, p < 0.001). Δ SMI/day (%) was positively correlated with daily caloric intake ≥80% of resting energy expenditure in weeks 2, 3, and 1-3 post-trauma and with protein intake >1.2 g/kg/d in weeks 3 and 1-3 post-trauma.

Conclusion

Loss of skeletal muscle mass is associated with poor prognosis and nutritional intake in patients admitted to hospital with abdominal trauma.

The more you have, the more you lose: Muscle mass changes in trauma patients with prolonged hospitalizations

INTRODUCTION

Sarcopenia is a clinically relevant loss of muscle mass with implications of increased morbidity and mortality in adult trauma populations.  Our study aimed to evaluate loss of muscle mass change in adult trauma patients with prolonged hospital stays.

METHODS

Retrospective analysis using institutional trauma registry to identify all adult trauma patients with hospital length of stay >14 days admitted to our Level 1 center between 2010 and 2017. All CT images were reviewed, and cross-sectional area (cm²) of the left psoas muscle was measured at the level of the third lumbar vertebral body to determine total psoas area (TPA) and Total Psoas Index (TPI) normalized for patient stature.  Sarcopenia was defined as a TPI on admission below gender specific thresholds of 5.45(cm²/m²) in men and 3.85(cm²/m²) in women.  TPA, TPI, and rates of change in TPI were then evaluated and compared between sarcopenic and non-sarcopenic adult trauma patients.

RESULTS

There were 81 adult trauma patients who met inclusion criteria. The average change in TPA was -3.8 cm² and TPI was -1.3 cm². On admission, 23% (n = 19) of patients were sarcopenic while 77% (n = 62) were not. Non-sarcopenic patients had a significantly greater change in TPA (-4.9 vs. -0.31, p<0.0001), TPI (-1.7 vs. -0.13, p<0.0001), and rate of decrease in muscle mass (p = 0.0002). 37% of patients who were admitted with normal muscle mass developed sarcopenia during admission.  Older age was the only risk factor independently associated with developing sarcopenia (OR: 1.04, 95%CI 1.00-1.08, p = 0.045).

CONCLUSION

Over a third of patients with normal muscle mass at admission subsequently developed sarcopenia with older age as the primary risk factor. Patients with normal muscle mass at admission had greater decreases in TPA and TPI, and accelerated rates of muscle mass loss compared to sarcopenic patients.

Effects of muscle quantity and bone mineral density on injury and outcomes in older adult motor vehicle crash occupants

Objectives: Quantify the independent and combined effects of abdominal muscle quantity and lumbar bone mineral density (BMD) on injury risk and in-hospital outcomes in severely injured motor vehicle crash (MVC) occupants ages 50 and older.Methods: Skeletal muscle area measurements of MVC occupants were obtained through semi-automated segmentation of an axial computed tomography (CT) slice at the L3 vertebra. An occupant height-normalized Skeletal Muscle Index (SMI) was calculated - a defining metric of sarcopenia and low muscle mass (sarcopenia thresholds: <38.5 cm2/m2 females; <52.4 cm2/m2 males). Lumbar BMD was obtained using a validated, phantomless CT calibration method (osteopenia threshold: <145 mg/cm3). SMI and BMD values were used to categorize occupants, and logistic regression was used to associate sarcopenia, osteopenia, and osteosarcopenia predictors to injury outcomes (e.g., Injury Severity Score (ISS), maximum Abbreviated Injury Scale (MAIS) score, fractures) and hospital outcomes (e.g., length of stay, ICU days).Results: Of the 336 occupants, 210 (63%) were female (mean ± SD: age 66.3 ± 10.6). SMI was 41.7 ± 8.0 cm2/m2 in females and 51.2 ± 10.8 cm2/m2 in males. Based on SMI, 40% of females and 55% of males were classified as sarcopenic. BMD was 163.2 ± 38.3 mg/cm3 in females and 164.1 ± 35.4 mg/cm3 in males, with 41% of females and 33% of males classified as osteopenic. Prevalence of both conditions (osteosarcopenia) was similar between females (21%) and males (22%). Incidence of low SMI and BMD increased with age. Sarcopenic individuals were less likely to sustain a MAIS 2+ thorax injury and had longer ICU stays. Osteopenic individuals were more likely to sustain upper extremity injuries and fractures, and were less likely to be discharged to a rehabilitation facility. Osteosarcopenic individuals were less likely to be ventilated or admitted to the ICU but tended to spend more time on the ventilator if placed on one.Conclusions: Osteosarcopenia was not associated with any injury outcomes, but sarcopenia was associated with thoracic injury and osteopenia was associated with upper extremity injury incidence. Sarcopenia was only associated with ICU length of stay, while osteopenia was only associated with discharge destination. Osteosarcopenia was associated with likelihood of being ventilated, being admitted to the ICU, and with increased length of ventilation.

The effect of sarcopenia on outcomes following orthopaedic surgery : a systematic review

AIMS

Sarcopenia is characterized by a generalized progressive loss of skeletal muscle mass, strength, and physical performance. This systematic review primarily evaluated the effects of sarcopenia on postoperative functional recovery and mortality in patients undergoing orthopaedic surgery, and secondarily assessed the methods used to diagnose and define sarcopenia in the orthopaedic literature.

METHODS

A systematic search was conducted in MEDLINE, EMBASE, and Google Scholar databases according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Studies involving sarcopenic patients who underwent defined orthopaedic surgery and recorded postoperative outcomes were included. The quality of the criteria by which a diagnosis of sarcopenia was made was evaluated. The quality of the publication was assessed using Newcastle-Ottawa Scale.

RESULTS

A total of 365 studies were identified and screened, 26 full-texts were reviewed, and 19 studies were included in the review. A total of 3,009 patients were included, of whom 2,146 (71%) were female and 863 (29%) were male. The mean age of the patients was 75.1 years (SD 7.1). Five studies included patients who underwent spinal surgery, 13 included hip or knee surgery, and one involved patients who underwent fixation of a distal radial fixation. The mean follow-up was 1.9 years (SD 1.9; 5 days to 5.6 years). There was wide heterogeneity in the measurement tools which were used and the parameters for the diagnosis of sarcopenia in the studies. Sarcopenia was associated with at least one deleterious effect on surgical outcomes in all 19 studies. The postoperative rate of mortality was reported in 11 studies (57.9%) and sarcopenia was associated with poorer survival in 73% (8/11) of these. The outcome was most commonly assessed using the Barthel Index (4/19), and sarcopenic patients recorded lower scores in 75% (3/4) of these. Sarcopenia was defined using the gold-standard three parameters (muscle strength, muscle quantity or quality, and muscle function) in four studies (21%), using two parameters in another four (21%) and one in the remaining 11 (58%). The methodological quality of the studies was moderate to high.

CONCLUSION

There is much heterogeneity in the reporting of the parameters which are used for the diagnosis of sarcopenia, and evaluating the outcome of orthopaedic surgery in sarcopenic patients. However, what data exist suggest that sarcopenia impairs recovery and increases postoperative mortality, especially in patients undergoing emergency surgery. Further research is required to develop processes that allow the accurate diagnosis of sarcopenia in orthopaedics, which may facilitate targeted pre- and postoperative interventions that would improve outcomes. Cite this article: Bone Joint J 2022;104-B(3):321-330.

Unseen Burden of Injury: Post-Hospitalization Mortality in Geriatric Trauma Patients

BACKGROUND/OBJECTIVES

Older adults are at risk for adverse outcomes after trauma, but little is known about post-acute survival as state and national trauma registries collect only inpatient or 30-day outcomes. This study investigates long-term, out-of-hospital mortality in geriatric trauma patients.

METHODS

Level I Trauma Center registry data were matched to the US Social Security Death Index (SSDI) to determine long-term and out-of-hospital outcomes of older patients. Blunt trauma patients aged ≥65 were identified from 2009 to 2015 in an American College of Surgeons Level 1 Trauma Center registry, n = 6289 patients with an age range 65-105 years, mean age 78.5 ± 8.4 years. Dates of death were queried using social security numbers and unique patient identifiers. Demographics, injury, treatments, and outcomes were compared using descriptive and univariate statistics.

RESULTS

Of 6289 geriatric trauma patients, 505 (8.0%) died as an inpatient following trauma. Fall was the most common mechanism of injury (n = 4757, 76%) with mortality rate of 46.5% at long-term follow-up; motor vehicle crash (MVC) (n = 1212, 19%) had long-term mortality of 27.6%. Overall, 24.1% of patients died within 1 year of trauma. Only 8 of 488 patients who died between 1 and 6 months post-trauma were inpatient. Mortality rate varied by discharge location: 25.1% home, 36.4% acute rehabilitation, and 51.5% skilled nursing facility, P < .0001.

CONCLUSION

Inpatient and 30-day mortality rates in national outcome registries fail to fully capture the burden of trauma on older patients. Though 92% of geriatric trauma patients survived to discharge, almost one-quarter had died by 1 year following their injuries.

Identification of Sarcopenia in Elderly Trauma Patients: The Value of Clinical Competency and Experience

INTRODUCTION

There is currently no standard definition of sarcopenia, which has often been associated with frailty. A commonly cited surrogate measure of sarcopenia is psoas muscle size. The purpose of this prospective study is to assess medical providers' capabilities to identify frail elderly trauma patients and consequent impact on outcomes after intensive care unit admission.

METHODS

Trauma intensive care unit patients over the age of 50 were enrolled. A preadmission functional status questionnaire was completed on admission. Attendings, residents, and nurses, blinded to their patient's sarcopenic status, completed surveys regarding 6-month prognosis. Chart review included cross-sectional psoas area measurements on computerized tomography scan. Finally, patients received phone calls 3 and 6 months after admission to determine overall health and functional status.

RESULTS

Seventy-six participants had an average age of 70 years and a corrected psoas area of 383 ± 101 mm²/m². Injury Severity Score distribution (17.2 ± 8.9) was similar for both groups. Patients also had similar preinjury activities of daily living. Both groups had similar hospital courses. While sarcopenic patients were less likely to be predicted to survive to 6 months (60% vs. 76%, P = 0.017), their actual 6-month mortality was similar (22% vs. 21%, P = 0.915).

CONCLUSION

Despite similar objective measures of preadmission health and trauma injury severity, medical providers were able to recognize frail patients and predicted they would have worse outcomes. Interestingly, sarcopenic patients had similar outcomes to the control group. Additional studies are needed to further delineate factors influencing provider insight into functional reserves of elderly trauma patients.

Low skeletal muscle mass predicts poor clinical outcomes in patients with abdominal trauma

OBJECTIVE

The aim of this study was to investigate whether low skeletal muscle mass is associated with clinical outcomes in patients with abdominal trauma.

METHODS

Patients presenting to our institution with abdominal trauma from January 2010 to April 2020 were retrospectively included. Low skeletal muscle mass was defined, using computed tomography, as skeletal muscle index (SMI) at the third lumbar vertebra below the lowest sex-specific quartile within 1 wk of admission. Clinical outcomes such as complications, hospital stay, and hospital cost were recorded, and univariate and multivariate analyses were performed.

RESULTS

Among 684 patients, 451 were eligible. Of these, 112 (24.8%) were classified as having low skeletal muscle mass, based on SMI diagnostic cutoff values (42.08 cm²/m² for men and 37.35 cm²/m² for women). Low skeletal muscle mass was significantly associated with longer hospital length of stay, longer intensive care length of stay, higher cost, higher frequency of mechanical ventilation, longer duration of vasopressor use, and higher incidence of massive transfusion and overall complications (P < 0.05). Subgroup analysis showed that pneumonia, acute gastrointestinal dysfunction, cholecystitis, digestive tract fistula, gastric fistula, and intestinal fistula were significantly associated with low skeletal muscle mass (P < 0.05). Multivariate analysis showed that low skeletal muscle mass was an independent risk factor for overall complications (odds ratio [OR], 2.44; 95% confidence interval [CI], 1.33-4.49; P = 0.004), hospital length of stay (OR, 3.49; 95% CI, 1.96-6.20; P < 0.001), and hospital cost (OR, 2.67; 95% CI, 1.48-4.80; P = 0.001).

CONCLUSIONS

Low skeletal muscle mass could be an independent predictor of poor clinical outcomes in patients with abdominal trauma.

High Prevalence of Sarcopenia in Older Trauma Patients: A Pilot Study

Sarcopenia is related to adverse outcomes in various populations. However, little is known about the prevalence of sarcopenia in polytrauma patients. Identifying the number of patients at risk of adverse outcome will increase awareness to prevent further loss of muscle mass. We utilized data from a regional prospective trauma registry of all polytrauma patients presented between 2015 and 2019 at a single level-I trauma center. Subjects were screened for availability of computed tomography (CT)-abdomen and height in order to calculate skeletal mass index, which was used to estimate sarcopenia. Additional parameters regarding clinical outcome were assessed. Univariate analysis was performed to identify parameters related adverse outcome and, if identified, entered in a multivariate regression analysis. Prevalence of sarcopenia was 33.5% in the total population but was even higher in older age groups (range 60–79 years), reaching 82 % in patients over 80 years old. Sarcopenia was related to 30-day or in-hospital mortality (p = 0.032), as well as age (p < 0.0001), injury severity score (p = 0.026), and Charlson comorbidity index (p = 0.001). Log rank analysis identified sarcopenia as an independent predictor of 30-day mortality (p = 0.032). In conclusion, we observed a high prevalence of sarcopenia among polytrauma patients, further increasing in older patients. In addition, sarcopenia was identified as a predictor for 30-day mortality, underlining the clinical significance of identification of low muscle mass on a CT scan that is already routinely obtained in most trauma patients.

Radiographic assessment of sarcopenia in the trauma setting: a systematic review

Background

Compared with similarly injured patients of a younger age, elderly patients have worse outcomes from acute injury. One factor adversely affecting outcomes is sarcopenia, which has been assessed in healthy elderly populations through established clinical and radiological criteria. However, in the acute care setting, no such criteria have been established. Sarcopenia has been opportunistically assessed via radiographic means but there is as of yet no gold standard. The purpose of this review is to summarize the radiological methods used to diagnose sarcopenia in the acute care setting, and suggest ways in which these methods may lead to a consensus definition of sarcopenia and its relationship to patient outcomes.

Methods

A systematic survey of medical databases was conducted, with 902 unique publications identified. After screening and application of inclusion and exclusion criteria, data regarding study population, outcome, imaging modality, and criteria for assessment of sarcopenia were extracted from 20 studies. Quality was assessed with the Newcastle-Ottawa Scale.

Results

CT was the imaging modality for 18 of the studies, with total psoas muscle cross-sectional area at the level of L3 and L4 being the dominant method for assessing sarcopenia. Adjustment for body morphology most commonly used patient height or L4 vertebral body area. The majority of articles found radiographically assessed sarcopenia to be significantly correlated to outcomes such as mortality, length of hospital stay, morbidity, and in-hospital complications

Conclusions

Establishing a consistent definition would strengthen its applicability and generalizability to admission and discharge planning.

Level of evidence

Systematic review, level III.

Impact of sarcopenia in trauma and surgical patient population: A literature review

Sarcopenia refers to the progressive and generalised loss of skeletal muscle mass and strength with a risk of adverse outcomes such as physical disability, poor quality of life and mortality. The present review explored the impact, diagnosis, prevention and management of sarcopenia in surgical and trauma patients. Recent evidence suggests that there are many factors contributing to its development other than age. Pathophysiology of sarcopenia is complex which makes its diagnosis difficult and there is no universal approach. It is a predictor of poor outcomes including post-operative complications, length of hospital stay and mortality in trauma and surgery patients. Sedentary lifestyle, age-dependent hormone and cytokine imbalance, decreased protein synthesis and regeneration, and motor unit remodelling are some of the main risk factors for sarcopenia. Dual energy X-ray absorptiometry, bio-electrical impedance analysis and computed tomography are frequently utilized for its diagnosis. Management of sarcopenia involves appropriate management of comorbidities, interventions to facilitate physical activities, nutrition interventions and pharmacotherapy.

Timing and methods of frailty assessments in geriatric trauma patients: A systematic review

INTRODUCTION

The trauma population is aging and better prognostic measures for geriatric trauma patients are required. Frailty rather than age appears to be associated with poor outcomes. This systematic review aimed to identify the optimum frailty assessment instrument and timing of assessment in patients aged over 65 years admitted to hospital after traumatic injury. The secondary aim was to evaluate outcomes associated with frailty in elderly trauma populations.

METHODS

This systematic review was registered with the PROSPERO International Prospective Register of Systematic Reviews (CRD42018090620). A MEDLINE and EMBASE literature search was conducted from inception to June 2019 combining the concepts of injury, geriatric, frailty, assessment and prognosis. Included studies were in patients 65 years or older hospitalised after injury and exposed to an instrument meeting consensus definition for frailty assessment. Study quality was assessed using criteria for review of prognostic studies combined with a GRADE approach.

RESULTS

Twenty-eight papers met inclusion criteria. Twenty-eight frailty or component instruments were reported, and assessments of pre-injury frailty were made up to 1-year post injury. Pre-injury frailty prevalence varied from 13% (13/100) to 94% (17/18), with in-hospital mortality rates from 2% (5/250) to 33% (6/18). Eleven studies found an association between frailty and mortality. Eleven studies reported an association between frailty and a composite outcome of mortality and adverse discharge destination. Generalisability and assessment of strength of associations was limited by single centre studies with inconsistent findings and overlapping cohorts.

CONCLUSIONS

Associations between frailty and adverse outcomes including mortality in geriatric trauma patients were demonstrated despite a range of frailty instruments, administering clinicians, time of assessment and data sources. Although evidence gaps remain, incorporating frailty assessment into trauma systems is likely to identify geriatric patients at risk of adverse outcomes. Consistency in frailty instruments and long-term geriatric specific outcome measures will improve research relevance.

LEVEL OF EVIDENCE

Level III prognostic.

Reliable and robust method for abdominal muscle mass quantification using CT/MRI: An explorative study in healthy subjects

Background

Quantification of abdominal muscle mass by cross-sectional imaging has been increasingly used to diagnose sarcopenia; however, the technical method for quantification has not been standardized yet. We aimed to determine an optimal method to measure the abdominal muscle area.

Methods

Among 50 consecutive subjects who underwent abdominal CT and MRI for possible liver donation, total abdominal muscle area (TAMA) and total psoas muscle area (TPA) at the L3 inferior endplate level were measured by two blinded readers. Inter-scan agreement between CT and MRI and inter-reader agreement between the two readers were evaluated using intraclass correlation coefficient (ICC) and within-subject coefficient of variation (WSCV). To evaluate the effect of measurement level, one reader measured TAMA and TPA at six levels from the L2 to L4 vertebral bodies.

Results

TAMA was a more reliable biomarker than TPA in terms of inter-scan agreement (ICC: 0.928 vs. 0.788 for reader 1 and 0.853 vs. 0.821 for reader 2, respectively; WSCV: 8.3% vs. 23.4% for reader 1 and 10.4% vs. 22.3% for reader 2, respectively) and inter-reader agreement (ICC: 0.986 vs. 0.886 for CT and 0.865 vs. 0.669 for MRI, respectively; WSCV: 8.2% vs. 16.0% for CT and 11.6% vs. 29.7% for MRI, respectively). In terms of the measurement level, TAMA did not differ from the L2_inf to L4_inf levels, whereas TPA increased with a decrease in measurement level.

Conclusions

TAMA is a better biomarker than TPA in terms of inter-scan and inter-reader agreement and robustness to the measurement level. CT was a more reliable imaging modality than MRI. Our results support the use of TAMA measured by CT as a standard biomarker for abdominal muscle area measurement.

The impact of computed tomography-assessed sarcopenia on outcomes for trauma patients - a systematic review and meta-analysis

INTRODUCTION

Sarcopenia is the progressive loss of skeletal muscle mass, strength and general decline in function associated with age, and has previously been shown to be a predictor of poor outcomes following surgery. Computed tomography (CT)-assessed sarcopenia has been proposed to be an independent predictor of outcomes for trauma patients. This systematic review aims to determine the impact of CT-assessed sarcopenia on patient mortality following trauma.

MATERIALS AND METHODS

A systematic review and meta-analysis of the literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. EMBASE, MEDLINE and CENTRAL databases were searched from database inception to 26 November 2018. Bibliographies of included articles were hand searched for potential articles. All observational studies which included trauma patients who had skeletal muscle mass or density assessed by CT were included in the review. Two authors independently performed the search with decisions reached by consensus. Meta-analysis was performed using Review Manager v5.3 using a random effects model. The primary outcome was all cause mortality, as established a priori.

RESULTS

Following an initial search of 1984 records, a total of 20 retrospective observational studies were included for qualitative analysis. Ten of these studies consisting of a pooled, partly-overlapping, 2867 patients were included in the meta-analysis. There was a wide variation in the reported prevalence of sarcopenia (25.0-71.1%). Sarcopenia patients were at a significantly increased risk of mortality during inpatient stay (RR 1.96 [95%CI 1.30-2.94], p =  0.001), at 30 days (RR 1.60 [95%CI 1.21-2.13], p =  0.001) and at 1-year (RR 3.11 [95%CI 1.94-4.96], p <  0.00001). There was no significant difference in total complications encountered, ICU duration or total inpatient stay.

CONCLUSION

Sarcopenia identified by CT is associated with increased risk of inpatient, 30-day, and 1-year mortality in trauma patients.

Recovery of the Psoas Muscle Index in Living Donors after a Right Lobe Hepatectomy for Liver Transplantation: A Single-Center Experience

OBJECTIVE

The development of sarcopenia leads to adverse postoperative outcomes. However, no study has investigated perioperative loss in core muscle and the correlation between core muscle and residual liver volume in living donors for liver transplant.

PATIENTS AND METHODS

A total of 457 adult healthy donors who underwent a right lobe hepatectomy without the middle hepatic vein for elective liver transplant were retrospectively analyzed. Abdominal computed tomography was performed within 1 month before surgery and the first week and 3 months after the surgery. The average psoas muscle area between lumbar vertebrae 3 and 4 was measured and normalized by height squared (psoas muscle index [PMI] = psoas muscle area/height²). The initial whole liver volume and remnant left lobe volume were measured on computed tomography images.

RESULTS

The study cohort included 279 men (61.1%) and 178 women (38.9%). The median preoperative PMIs were 420.9 mm²/m² (interquartile range, 360.6-487.0 mm²/m²) in men and 280.9 mm²/m² (interquartile range, 243.5-318.7 mm²/m²) in women. The PMIs in men and women significantly decreased during the first week after surgery, and gradually recovered to preoperative levels during the first 3 months after surgery. Based on the ratio between the remnant left lobe and initial whole liver volume (≥30%), the increase in remnant left lobe volume was not correlated with the decrease in PMI on postoperative day 7. A postoperative U-shaped recovery in the core muscles was present in both male and female donors, independent of the remnant liver ratio.

CONCLUSIONS

Despite the requirements of partial liver regeneration and surgical wound repair, healthy donors did not suffer from sustained core muscle loss after surgery.