Stesura Seveso Archivio Italiano di Urologia e Andrologia 2025; 97(2):13939 1 ORIGINAL PAPER trauma may account up to 20%, depending on the loca- tion and registry (3). Young males (mean age 30 years) who participate in sports, motor vehicle accidents, assaults, or falls are more likely to sustain traumatic renal injuries. In the paediatric population, falls (27%) and pedestrian accidents (13%), rather than motor vehicle acci- dent (MVA) (30%), were the primary causes of blunt trau- ma (2, 5). Renal trauma caused by motor vehicle crashes is associated with high morbidity and mortality. In addi- tion, these events can cause a loss of 1-1.5% of the gross national product in developing countries (6). The priority of renal trauma management is primarily to prevent death by controlling haemorrhage, preserving nephrons, and avoiding complications. In recent decades, trauma management has evolved toward a non-invasive approach through non-operative management (NOM). It maintains safety with better outcomes (7-9). This approach applies to both paediatric and adult popula- tions. The absolute indications for renal intervention are hemodynamic instability, unresponsiveness to aggressive resuscitation due to renal haemorrhage, grade 5 vascular injury, and extensive perirenal hematoma found during laparotomy for associated injuries. In addition to the medical approach and interventions required, bed rest after renal trauma is a very common practice until haema- turia resolves (7, 10, 11). However, this policy appears to be controversial, mainly because the degree of haematuria does not seem to correlate with improvement in symp- toms or mobility that can lead to prolonged length of stay (LOS) with associated risks of venous thromboembolism (VTE) and hospital-acquired infections (12-14). In addi- tion, hospitals may experience resource loss and func- tional decline. LOS can be influenced by the patient's age, gender, complications, comorbidities, and history of mental illness. The severity of the injury and the inter- ventions received may also be the best predictors of LOS. Furthermore, post-traumatic pain and surgery can extend a patient's LOS. Some studies have shown that prolonged LOS may increase the mortality rate of trauma patients in the hospital (15, 16). Several studies have reported that the average safe LOS is less than 4 days for isolated renal injury at all levels of trauma, using a more relaxed policy regarding mobiliza- tion, and less than 2 days for hepatosplenic trauma, with- out readmission (17). This suggests that a short rest peri- od remains safe in renal trauma. This study was conduct- Background: Renal trauma represents a critical injury requiring precise management with the length of hospital stay (LOS) serving as a key metric for trauma care. Recognizing the factors contributing to extend- ed LOS is essential for optimizing treatment strategies and enhancing patient outcomes. This study aims to analyse the risk factors influencing LOS in patients with renal trauma. Methods: This retrospective cohort study was conducted at Dr. Saiful Anwar General Hospital, Malang, analysing medical record data of renal trauma patients from 2013 to 2023. Collected variables included demographics, mechanism of injury, associated injuries, hemodynamic status upon admission, injury severity, haemoglobin levels, LOS, management approach, and mortality outcomes. Univariate and multivariate analyses were performed to assess the impact of each variable on LOS. Results: 119 renal trauma patients were included. The average age was 40.1 ± 16.86 years, and 77.3% of the participants were male. The average LOS was 6.85 ± 3.85 days. Blunt renal trauma was the predominant mechanism, accounting for 95.8% of cases, while associated injuries were observed in 53.1% of patients. Upon hospital admission, 66.4% of cases presented with stable hemodynamic status, and non-operative management was employed in 92.4% of cases. Prolonged LOS was significant- ly associated with age, blunt trauma, associated injuries, hemo- dynamic instability, and low haemoglobin levels in both univari- ate and multivariate analyses. Conclusions: Age, mechanism of injury, associated injuries, hemodynamic status at admission, and haemoglobin levels sig- nificantly impact LOS in renal trauma patients. Identifying these factors may aid in improving patient management and reducing hospitalization duration. KEY WORDS: Length of stay; Renal; Risk factors; Trauma. Submitted 1 May 2025; Accepted 1 June 2025 INTRODUCTION Renal trauma is an injury to the blood vessels and/or parenchyma of the kidney, resulting in bleeding or injury to the collecting system with possible urine leakage (1). The kidney is the third most commonly injured organ in abdominal trauma, after the spleen and liver (2). Renal trauma contributes about 1% to 5% of all traumas, most of which are caused by blunt abdominal trauma (80% to 90%) (3, 4). Although uncommon, penetrating renal Analysis of factors associated with length of stay in renal trauma patients: A single-centre retrospective study Paksi Satyagraha, Besut Daryanto, Bagas Wilianto, Fauzan Kurniawan Dhani Department of Urology, Faculty of Medicine Universitas Brawijaya, Dr. Saiful Anwar General Hospital, Malang, Indonesia. DOI: 10.4081/aiua.2025.13939 Summary Archivio Italiano di Urologia e Andrologia 2025; 97(2):13939 P. Satyagraha, B. Daryanto, B. Wilianto, F. Kurniawan Dhani 2 ed to analyse the risk factors that influence the LOS of renal trauma patients at Dr. Saiful Anwar General Hospital in Malang, Indonesia. MATERIALS AND METHODS Study design This study is a retrospective cohort study conducted at Dr. Saiful Anwar General Hospital Malang, Indonesia, based on medical record data. The study population included all patients who experienced renal trauma from January 2013 to December 2023. This research adheres to the principles outlined in the Declaration of Helsinki and has received approval from the Dr. Saiful Anwar General Hospital Ethics Committee under protocol number 400/223/K.3/102.7/2024. The inclusion criteria were trauma patients aged >18 years admitted to Emergency Department (ED) of Dr. Saiful Anwar General Hospital diagnosed with renal trauma, con- firmed by contrast-enhanced CT imaging or intraopera- tive findings. Those who injured > 2 weeks before admis- sion were excluded. The exclusion criteria were extended to patients from another hospital or with iatrogenic renal injuries. Trauma patients are initially assessed by emergency med- icine physicians and subsequently co-managed with the trauma surgery team. Renal trauma is typically identified via contrast-enhanced CT imaging in hemodynamically stable patients, while unstable patients may undergo immediate surgical exploration. Patient data Data were extracted by authors BW and FKD. A random 10% sample of records underwent double data entry for consistency. Definitions of comorbidities were based on ICD-10 codes, and considered clinical variables were hypotension (defined as systolic blood pressure < 90 mmHg), age, gender, mechanism of injury, associated injuries, haemoglobin levels, and hemodynamic status upon arrival, as well as injury severity, LOS, patient man- agement, and mortality rate. Associated injuries included other traumas aside from renal trauma, such as injuries to the brain, gastrointesti- nal tract, thorax, and bones. The American Association for the Surgery of Trauma (AAST) grading system was applied to assess renal trauma, with AAST Grades I-III classified as low grade and AAST Grades IV-V as high grade. LOS was determined from the time the patient arrives at the ED until discharge or death. Operative therapies per- formed include percutaneous urinoma drainage, DJ stent insertion, renorrhaphy, and nephrectomy. Statistical analysis Continuous variables were summarized as medians with interquartile ranges (IQR) due to non-normal distribution, while categorical variables were presented as frequencies and percentages. Univariate analysis was conducted using the Chi-square test to evaluate associations between cate- gorical variables and LOS. Variables with clinical rele- vance or a p-value < 0.10 in univariate analysis were included in a multivariable linear regression model to identify independent predictors of increased LOS in renal trauma patients. Statistical significance was defined as a two-tailed p-value < 0.05. All analyses were performed using IBM SPSS Statistics for Windows, version 23.0 (IBM Corp., Armonk, NY, USA). RESULTS The total number of patients studied was 119, consisting of 92 males (77.3%) and 27 females (22.7%), as shown in Table 1. The average age of patients with renal trauma was 40.1 + 16.86 years, and the average haemoglobin level of 11.41 + 7.98 g/dL. The most common mechanism of injury was blunt injury, with 114 cases (95.8%) with an average length of stay of up to 6.85 days, or approxi- mately 1 week. In addition, 62 patients (52.1%) had injuries restricted to renal trauma, and 57 patients (47.9%) did not. On arrival, 79 patients (66.4%) had sta- ble hemodynamic status, and 40 patients (33.6%) had unstable hemodynamic status. Non-operative manage- ment was the predominant approach, implemented in 110 cases (92.4%), while immediate operative manage- ment was performed in 9 cases (7.6%). The operative interventions included nephrectomy in six cases, renor- rhaphy in two cases, and percutaneous urinoma drainage and DJ stent insertion in one case. Based on injury sever- ity, 84 patients (70.6%) had low-grade injuries (Grades I- Table 1. Patient characteristics. N % Number of patient 119 Age, years (median) 40.1 ± 16.86 Gender Male 92 77.3 Female 27 22.7 Haemoglobin, g/dL (SD) 11.41 ± 7.98 LOS, days (SD) 6.85 ± 3.85 MOI Blunt 114 95.8 Penetrating + Iatrogenic 5 4.2 Associated Injuries 62 52.1 Brain 4 6.5 GI 32 51.6 Thorax 9 14.5 Bone 17 27.4 Haemodynamic Stable 79 66.4 Unstable 40 33.6 Renal Trauma Grade Low (I, II, III) 84 70.6 High (IV, V) 35 29.4 Management Non-Operative 110 92.4 Operative 9 7.6 Nephrectomy 6 66.7 Renorrhaphy 2 22.6 DJ Stent Insertion + 1 10.7 Percutaneous Urinoma Drainage SD: Standard Deviation; LOS: Length of Stay; MOI: Mode of Injury. Archivio Italiano di Urologia e Andrologia 2025; 97(2):13939 3 Analysis of factors associated with length of stay in renal trauma patients... III), while 35 patients (29.4%) had high-grade injuries (Grades IV-V). The mortality rate was 10.1% (12 patients), while 107 patients (89.9%) survived. Based on the analysis of patient mortality data, a total of 12 deaths were recorded among 119 patients (Table 2). Of these 12 cases, none were attributed solely to renal trauma. Notably, 3 patients (25%) presented with con- comitant head trauma, 5 patients (42%) had gastroin- testinal trauma, and 4 patients (33%) experienced tho- racic trauma. Univariate analysis indicated that patients over 60 years of age had a 2.47-fold increased risk of prolonged LOS (p = 0.018). Regarding the MOI, penetrating or iatrogenic trauma was associated with an 8.00-fold higher risk of prolonged LOS compared to blunt trauma (p = 0.033). The presence of associated injuries significantly increased the risk of prolonged LOS (OR 9.26; 95% CI: 3.63-23.63; p < 0.001). Furthermore, patients presenting with unsta- ble hemodynamics (OR 10.38; 95% CI: 5.37-33.38; p < 0.001) and hemoglobin levels below 10 g/dL (OR 24.62; 95% CI: 8.99-63.70; p < 0.001) were at markedly higher risk of prolonged LOS (Table 3). Multivariate analysis confirmed the independent associa- tion of all five factors with prolonged hospital stay: age > 60 years (OR 2.79; 95% CI: 1.60-18.92; p = 0.019), pen- etrating or iatrogenic trauma (OR 4.47; 95% CI: 3.03- 75.14; p = 0.009), presence of associated injuries (OR 1.80; 95% CI: 1.32-28.04; p = 0.020), unstable hemody- namics (OR 2.22; 95% CI: 2.33-37.04; p = 0.002), and hemoglobin < 10 g/dL (OR 3.93; 95% CI: 8.74-96.02; p < 0.001) (Table 3). DISCUSSION The age of patients with renal trauma in this study was 40.1 years, and male gender was more frequent. In a study conducted in South Africa in 2019, the average age of patients with renal trauma was 27 years (18). Similarly, a 2019 study in New York found that the average kidney trauma patient was male, with an average age of 33 (19). According to a report from the Japan Trauma Database from 2004-2018, 74.2% of renal trauma patients were males aged below 60 years, with the most common mech- anism of injury being blunt trauma caused by traffic acci- dents and falls from heights (20). The probable explana- tion for this is that renal injuries become more common in this age group because the subjects included are more frequently involved in high-risk activities and mobility, particularly in traffic and sports. Additionally, Indonesian males generally use motorcycles for transportation, rais- ing the risks of MVAs (21). In this study, age was one of the factors that could prolong LOS, but gender was not a significant factor. The mechanism of injury in renal trauma is mostly due to blunt force injuries caused by motor vehicle collisions, falls from height, and sports injuries. A study showed that blunt renal trauma is one of the predictive factors for longer LOS compared to pene- trating trauma (6, 16). A study reported the mean LOS of road traffic related injuries was 6.8 days with a LOS range of 1 to 105 days (22). However, another study showed significantly different results, in which the median LOS was 2.85 days (6, 16). Other associated injuries also have the poten- tial to prolong LOS due to the additional interventions and follow-up care required. Moore et al. found that the anatomical loca- tion of the injury can be a predictor of pro- longing LOS in patients, such as in patients who also had spinal cord injuries, which resulted in 3.1 days longer LOS than patients with lower limb injuries (6, 22). Traumatic incidents may cause hemodynam- ic problems due to bleeding and vascular injury. The hemodynamic condition of a renal trauma patient on arrival determines both the management and the length of stay. Table 2. Characteristic renal trauma patient mortality. N % Mortality 12/119 10 Renal Trauma Grade Low (I, II, III) 10 83 High (IV, V) 2 17 Haemodynamic Stable 5 42 Unstable 7 58 Associated Injuries Brain 3 25 GI 5 42 Thorax 4 33 Table 3. Uni- and multivariate regression analysis for factors associated with LOS in renal trauma patients. Univariate analysis Multivariate analysis OR 95% CI P value OR 95% CI P value Age < 60 vs > 60 2.47 0.62-9.73 0.018 * 2.799 1.60-18.92 0.019 * Gender Male vs Female 1.10 0.42-2.69 0.829 MOI Blunt vs Penetrating + Iatrogenic 8.00 0.86-74.08 0.033 * 4.473 3.03-75.14 0.009 * Associated Injuries Yes vs No 9.26 3.63-23.63 0.000 * 1.807 1.32-28.04 0.020 * Haemodynamic Stable vs Unstable 10.38 5.37-33.38 0.000 * 2.229 2.33-37.04 0.002 * Grade Low vs High 2.53 1.16-5.51 0.170 Haemoglobin > 10 vs < 10 24.62 8.99-63.7 0.000 * 3.929 8.74-96.02 0.000 * Management Non-Operative vs Operative 4.11 0.97-17.39 0.060 Mortality Yes vs No 1.97 0.59-6.55 0.261 * Significant result. MOI: Mechanism of Injury; CI: Confidence Interval; OR: Odd Ratio. Archivio Italiano di Urologia e Andrologia 2025; 97(2):13939 P. Satyagraha, B. Daryanto, B. Wilianto, F. Kurniawan Dhani 4 Hemodynamic instability may include hypotension, shock due to hematoma, and massive bleeding, resulting in decreased haemoglobin. Low haemoglobin levels (< 10 g/dL) will also delay discharge. Hemodynamic instability increases the risk of prolonged LOS. Meanwhile, patients with stable hemodynamic do not need to undergo opera- tive procedures, so their length of stay will be shorter (6). Patients who arrived with hemodynamic stability, despite having a high severity of injury, were recommended to NOM. In this study, renal trauma management was not associated with a significant risk of patient LOS. A study showed that there is a correlation between the medical management provided and the patient's LOS, i.e., patients with NOM tend to have a shorter LOS than patients with operative management (6, 20). Many studies have confirmed the safety of NOM in renal trauma, and it has become the standard of care for most patients with renal trauma (20, 23, 24). The success rate of NOM in hemodynamically stable patients reaches 80%, even in patients with high-grade severity (24). Nevertheless, emergency operative treatment of injuries in patients with hemodynamic instability is still performed for certain indications (12), NOM has demonstrated favourable outcomes and remains the preferred initial treatment for isolated renal trauma in patients with stable hemodynamic status, even in cases of high-grade injuries. In cases where complications arise (like urinoma, or infec- tion), minimally invasive procedures such as percuta- neous drainage of urinomas can be employed effectively (25). Factors that determine the choice of management include patient stability, the degree of renal injury, and the presence of associated injuries, which are the most com- mon reasons for renal surgical exploration (26). The study showed that 10.1% of renal trauma patients died (26). Our study also indicates that renal trauma patients, in the absence of associated injuries, did not experience any fatalities. All fatalities in renal trauma cases were observed exclusively in the presence of con- comitant injuries. This is consistent with findings from a 9-year study on renal injury conducted in Australia, which reported that renal injury was not identified as the cause of death in any of the cases. Overall, 17 patients in that study succumbed within the first 24 hours of admis- sion due to severe multi-trauma (27). Post-traumatic mortality was also not a significant factor affecting LOS. This is consistent with the results of the San Francisco study, which found that patients who died had a mean LOS of 6.6 days shorter than patients who were dis- charged (p < 0.01) (6). A patient's hospital care may con- clude upon their discharge, transfer, or death. The mean LOS for transferred patients was 5.8 days longer than for discharged patients (6, 28). This study has several limitations that need to be consid- ered in interpreting the results. Firstly, the retrospective design of the study, which was conducted in one health- care center, limits the generalizability of the findings to a wider population or to hospitals with different character- istics. In addition, the relatively limited sample size may also affect the statistical power and external validity of the findings. Therefore, further studies with a prospective design and multicentre coverage are needed to verify the results and improve the validity of the findings. CONCLUSIONS This study concludes that older age, blunt force injury, associated injuries, hemodynamic instability, and haemo- globin level all have an impact on the length of hospital stay in patients with renal trauma. Proper management and clinical condition at the time of admission also deter- mine the length of hospital stay, which affects patient out- come. Further studies with larger samples and other parameters that play a role in the hospital management of renal trauma patients are needed to reduce disability and mortality rates and improve survival. REFERENCES 1. Baghdanian AH, Baghdanian AA, Armetta A, et al. Utility of MDCT findings in predicting patient management outcomes in renal trauma. Emerg Radiol. 2017; 24:263-72. 2. Mingoli A, La Torre M, Migliori E, et al. Operative and nonoper- ative management for renal trauma: comparison of outcomes. A sys- tematic review and meta-analysis. Ther Clin Risk Manag. 2017; 13:1127-38. 3. Zabkowski T, Skiba R, Saracyn M, Zielinski H. 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Correspondence Besut Daryanto (Corresponding Author) urobes.fk@ub.ac.id Department of Urology, Faculty of Medicine Universitas Brawijaya, Dr. Saiful Anwar General Hospital, Malang, Indonesia Jaksa Agung Suprapto No. 2, Klojen, Malang, East Java, Indonesia 65111 Paksi Satyagraha uropas.fk@ub.ac.id Bagas Wilianto bagaz.dr@gmail.com Fauzan Kurniawan Dhani fauzankurniawandhani@gmail.com Department of Urology, Faculty of Medicine Universitas Brawijaya, Dr. Saiful Anwar General Hospital, Malang, Indonesia