RETRACTED: Analysing predictors of surgical site infections in patients undergoing emergency surgery for traumatic pulmonary haemorrhage
Abstract
Identifying predictors for surgical site infections (SSIs) after emergency surgical treatment for traumatic pulmonary haemorrhage (TPH) is crucial for improving patient outcomes. This study aims to ascertain these predictors. In this comprehensive retrospective study, conducted from January 2020 to December 2023 at our institution, 75 patients were analysed, including a case group of 25 patients with SSIs and a control group of 50 without SSIs post-TPH surgery. Inclusion criteria focused on patients aged 18 and above undergoing thoracotomy or minimally invasive thoracic surgery for TPH. Exclusion criteria included compromised immune systems, chronic pulmonary diseases, prior thoracic surgery or active infections at admission. We assessed several predictors: anaemia; operation time over 2 h; hospital stay over 5 days; intraoperative blood loss exceeding 500 mL; body mass index (BMI) ≥25 kg/m2; age ≥ 50 years; use of surgical drains; the presence of open wounds; diabetes mellitus and non-prophylactic antibiotic use. Statistical analysis involved univariate and multivariate logistic regression, using SPSS Version 27.0. Univariate analysis revealed significant associations between SSIs and surgical drain placement, diabetes mellitus, open wounds and non-prophylactic antibiotic use (p < 0.01). Multivariate analysis confirmed these factors as significant predictors of SSIs, with notable odds ratios. Other variables like anaemia, extended hospital stay, excessive intraoperative blood loss, older age and higher BMI did not significantly predict SSIs. Significant predictors for SSIs following TPH surgery include surgical drain placement, diabetes mellitus, open wounds and non-prophylactic antibiotic use. Identifying and managing these risks is crucial in clinical practice to reduce SSIs incidence and improve patient outcomes.
1 INTRODUCTION
Traumatic pulmonary haemorrhage (TPH), bleeding into the lung parenchyma and the pleural cavity due to severe blunt or penetrating chest trauma, represents a critical medical emergency.1, 2 This condition, characterised by bleeding into the lung parenchyma and the pleural cavity, necessitates immediate and effective medical intervention.3, 4 Surgical treatment, particularly in cases where conservative management fails, plays a pivotal role in managing such severe instances of TPH.5, 6 However, these emergency surgical interventions for TPH, despite their life-saving potential, are associated with a well-defined range of complications.7 These include, but are not limited to, surgical site infections (SSIs), respiratory complications such as pneumonia and acute respiratory distress syndrome (ARDS).8, 9 Amongst these, SSIs emerge as a prominent concern due to their frequency, potential severity and impact on patient recovery. Surgical management of TPH, often dictated by the presence of hemothorax, extensive lung lacerations or traumatic pneumothorax, requires an expedited and meticulous approach. This urgency, often combined with the patient's compromised health status due to the trauma, significantly increases the risk of postoperative complications.10 SSIs, in particular, are noteworthy for its frequent occurrence, the potential for grave outcomes and the substantial impact it has on patient recovery times and healthcare system burdens.11
The challenge of managing SSIs in the context of TPH surgery is further compounded by the unique conditions of these cases. The initial traumatic injury, often involving significant chest trauma, predisposes patients to a higher risk of infection. The presence of blood in the pleural cavity, a common consequence of TPH, creates an environment conducive to bacterial proliferation. Additionally, the emergent nature of TPH surgeries heightens the risk of infection, as time constraints and the critical condition of patients can limit the thoroughness of standard infection control practices. The aetiology of SSIs following TPH surgery is complex and typically involves multiple factors. Bacterial contamination can occur at various stages: at the initial injury site, intraoperatively or during the postoperative period.12, 13 The types of organisms responsible for these infections vary, with a propensity towards both common skin flora and more virulent hospital-acquired pathogens. The spectrum of these infections ranges from superficial incisional infections, which impact the skin and subcutaneous tissue, to more severe deep surgical site infections, which can involve muscles and fascial layers. In extreme cases, these infections can progress to systemic involvement, leading to life-threatening conditions like sepsis or septic shock.
This study aims to thoroughly identify and analyse the multifactorial predictors associated with SSIs in the aftermath of emergency surgical interventions for TPH. This includes a detailed examination of patient demographics, the specific nature and severity of the trauma, the type and duration of surgical intervention and the postoperative care protocols. By gaining a comprehensive understanding of these predictors, the study seeks to inform clinical practice, improve surgical outcomes and develop targeted strategies for the prevention and management of SSIs in this high-risk patient population.
2 MATERIALS AND METHODS
2.1 Study design
A retrospective analysis was undertaken at our institution to ascertain the predictors associated with SSIs after emergency surgical interventions for TPH. This investigation spanned from January 2020 through December 2023. A total of 25 patients who manifested SSIs following surgery were selected for the case group. To facilitate a comparative analysis, a control group was established, comprising 50 patients treated during the same timeframe who did not experience SSIs post-surgery. This approach was designed to ensure comparability between the two patient groups. Informed consent was obtained from all study participants, affirming their participation and understanding of the study's aims and procedures. The research methodology, objectives and protocols underwent review and received approval from the ethics committee of our hospital.
2.2 Inclusion and exclusion criteria
This study focuses on participants aged 18 years and above, regardless of gender, diagnosed with TPH requiring emergency surgical intervention. The surgical interventions include thoracotomy and minimally invasive thoracic surgery for TPH from January 2020 to December 2023. All participants must have provided informed consent, ensured voluntary participation and understood the research's objectives and procedures.
Excluded are individuals with conditions that compromise the immune system, such as HIV/AIDS, those on chronic steroid therapy or chemotherapy and patients with a history of chronic pulmonary diseases like chronic obstructive pulmonary disease or cystic fibrosis. Also excluded are patients who have undergone thoracic surgical procedures in the past year, patients presenting with any active infection at the time of admission, including pre-existing pulmonary infections, and patients whose hospital stay post-surgery was less than 24 h or exceeded 30 days, as these durations could bias the assessment of surgical site infections.
2.3 Assessment of predictors for surgical site infections
To identify factors that could influence surgical outcomes, including the incidence of SSIs, our study gathered patient data. Key variables collected included: the presence of anaemia; operation time, specifically cases exceeding 2 h; hospital stay durations over 5 days; intraoperative blood loss of 500 mL or more; body mass index (BMI) equal to or greater than 25 kg/m2; age of 50 years or older; the use of surgical drains; the presence of open wounds; the presence of diabetes mellitus and cases where antibiotics were not used prophylactically. The selection of these variables aimed to evaluate factors that could impact the surgical process and subsequent recovery, focusing on the risk and development of SSIs. The data collection process adhered to ethical standards to ensure the accuracy and reliability of the data for future analyses.
2.4 Statistical analysis
In our study, statistical analyses were meticulously conducted to identify key factors influencing surgical outcomes. The primary approach involved both univariate and multivariate analyses. Initially, univariate analysis was employed to evaluate the individual impact of each variable. This analysis facilitated the identification of significant predictors amongst the collected data, including demographic factors, clinical parameters and intraoperative variables. Subsequently, multivariate logistic regression analysis was implemented to discern the independent effect of each variable whilst controlling for potential confounders. This analysis was crucial in determining the relative contribution of each factor to the outcome, thus allowing for a more accurate and comprehensive understanding of the complex interplay of variables influencing surgical success and postoperative complications. Statistical significance was set at a p-value less than 0.05. Statistical computations and analyses in this research were executed using version 27.0 of the SPSS software package.
3 RESULTS
3.1 Univariate analysis of predictors associated with surgical site infections
In the conducted study, a comprehensive statistical evaluation was performed to ascertain the impact of various factors on the occurrence of SSIs in patients undergoing surgery for TPH. Amongst the variables analysed, certain factors exhibited a statistically significant association with the incidence of SSIs. Notably, the placement of surgical drains, the presence of diabetes mellitus, an open wound and the lack of prophylactic antibiotic use were identified as prominent predictors, each demonstrating a statistically significant correlation with postoperative infections (p < 0.01). These findings suggest that patients exhibiting these characteristics require closer monitoring and potential intervention strategies to mitigate the risk of SSIs. Conversely, factors such as anaemia, length of hospital stay exceeding 7 days, intraoperative blood loss of 500 mL or more, age over 50 years, body mass index of 25 kg/m2 or higher and operation time of 5 h or more did not show a significant difference between infected and non-infected groups (p-values ranging from 0.332 to 1). This indicates that within the context of our study, these factors were not predictive of SSIs outcomes. The results underscore the importance of specific clinical interventions and preoperative planning, particularly in managing patients with diabetes, open wounds and those not receiving prophylactic antibiotics (Table 1).
| Factors | Infected (n = 25) | Non-infected (n = 50) | χ2 | p-Value |
|---|---|---|---|---|
| Anaemia | 11 (44.0%) | 22 (44.0%) | 0 | 1 |
| Hospital stay (>7 days) | 14 (56.0%) | 28 (56.0%) | 0 | 1 |
| Intraoperative blood loss (≥500 mL) | 15 (60.0%) | 30 (60.0%) | 0 | 1 |
| Age (≥50 years) | 19 (76.0%) | 36 (72.0%) | 0.04 | 0.8488 |
| Body mass index (≥25 kg/m2) | 16 (64.0%) | 27 (54.0%) | 0.29 | 0.5898 |
| Operation time (≥5 h) | 14 (56.0%) | 20 (40.0%) | 0.94 | 0.332 |
| Placement of surgical drains | 24 (96.0%) | 16 (32.0%) | 8.41 | <0.01 |
| Diabetes mellitus | 17 (68.0%) | 9 (18.0%) | 12.02 | <0.01 |
| Open wound | 19 (76.0%) | 10 (20.0%) | 13.52 | <0.01 |
| Non-prophylactic antibiotic use | 22 (88.0%) | 13 (26.0%) | 13.73 | <0.01 |
3.2 Multivariate logistic regression analysis of predictors associated with surgical site infections
The results from our multivariate logistic regression analysis offer insight into the significant predictors for SSIs in patients treated for TPH (Table 2). The analysis delineated several factors with corresponding beta (β) values, indicating the magnitude and direction of the association with SSIs, along with odds ratios (OR) and their 95% confidence intervals (CI), providing a measure of the strength of these associations. The placement of surgical drains emerged as a factor with a substantial association with the occurrence of SSIs, exhibiting an OR of 3.83, suggesting that patients with drains were approximately four times more likely to develop infections compared to those without. This factor's significance was further supported by its p-value of 0.028, indicating statistical significance.
| Factors | β-Value | Standard error value | Wald value | OR value | 95% CI for OR | p-Value |
|---|---|---|---|---|---|---|
| Placement of surgical drains | 0.347 | 1.408 | 4.103 | 3.83 | 1.329–4.905 | 0.028 |
| Diabetes mellitus | 0.295 | 1.024 | 3.482 | 3.194 | 1.117–4.251 | 0.045 |
| Open wound | 0.286 | 1.293 | 3.241 | 3.008 | 1.103–4.105 | 0.012 |
| Non-prophylactic antibiotic use | 0.247 | 1.226 | 2.749 | 2.55 | 1.018–3.731 | 0.031 |
- Abbreviations: CI, confidence interval; OR, odds ratio.
Additionally, the presence of diabetes mellitus was also identified as a significant predictor, with patients having this condition being over three times more likely to encounter postoperative infections, as reflected by an OR value of 3.194 and a p-value of 0.045. An open wound at the time of surgery was another notable predictor, with an OR of 3.008, underscoring the increased risk of SSIs in such cases. The analysis reported this factor to have a p-value of 0.012, reinforcing its statistical significance. Lastly, the non-prophylactic use of antibiotics was associated with a more than twofold increased risk of SSIs (OR = 2.55), with a p-value of 0.031, denoting a significant contribution to the risk of infection. These identified predictors are integral in understanding the multifactorial nature of surgical site infections. Their statistical significance highlights the need for tailored perioperative management strategies to mitigate the identified risks, especially in vulnerable patient populations.
4 DISCUSSION
TPH is a critical medical condition characterised by severe bleeding within the lungs, often resulting from traumatic injuries such as accidents or falls.14 Emergency surgical intervention is frequently necessary to control bleeding, repair damaged blood vessels and stabilise patients in life-threatening situations.15 Whilst such surgeries are essential for saving lives, they are not without risks, and one significant complication that can arise is SSIs. SSIs pose a considerable challenge in the postoperative management of TPH patients.16, 17 It can lead to prolonged hospital stays, increased healthcare costs and in severe cases, life-threatening systemic infections.18 Despite advances in surgical techniques and perioperative care, the incidence of SSIs following emergency surgical treatment for TPH remains a topic of concern. Identifying the predictors associated with SSIs in this specific patient population is of paramount importance.19 It not only aids in risk stratification but also guides healthcare providers in implementing preventive measures and tailored interventions.20 To date, limited research has been conducted to comprehensively investigate these predictors in the context of emergency surgical treatment for TPH.21
In this study, we conducted a rigorous univariate analysis to explore the potential predictors contributing to SSIs in patients undergoing surgery for TPH. Our comprehensive statistical evaluation revealed several key findings that shed light on the association between various factors and the incidence of SSIs. Firstly, we observed that certain factors exhibited a significant correlation with the occurrence of SSIs. Notably, the placement of surgical drains, the presence of diabetes mellitus, an open wound and the absence of prophylactic antibiotic use were identified as prominent predictors. Patients with these characteristics demonstrated a significantly higher likelihood of developing postoperative infections, as indicated by p-values of less than 0.01. These findings underscore the importance of careful monitoring and tailored interventions for patients with these predictors to mitigate the risk of SSIs.
Our analysis revealed that factors such as anaemia, extended hospital stays exceeding 7 days, intraoperative blood loss of 500 mL or more, age over 50 years, BMI equal to or higher than 25 kg/m2 and prolonged operation times of 5 h or more did not exhibit a statistically significant difference between infected and non-infected groups (p-values ranging from 0.332 to 1). These findings suggest that, within the scope of our study, these factors were not predictive of SSIs outcomes. It is essential to recognise that whilst these variables may not be directly associated with SSIs in our cohort, they still hold clinical relevance and may influence other aspects of patient care and surgical outcomes. Our results emphasise the need for tailored clinical interventions and preoperative planning, particularly for patients with diabetes, open wounds and those not receiving prophylactic antibiotics. These individuals should be closely monitored, and proactive measures should be implemented to reduce the risk of SSIs. Moreover, the lack of significance in certain variables highlights the importance of considering a multifactorial approach when assessing SSIs risk, as these factors may interact with others to influence infection outcomes.
Our multivariate logistic regression analysis further delved into the significant predictors for SSIs in patients undergoing surgical treatment for TPH. This advanced analysis provided a more comprehensive understanding of the interplay between various factors and their impact on the risk of SSIs. The placement of surgical drains emerged as a significant predictor, with patients having drains being approximately four times more likely to develop infections compared to those without drains (OR = 3.83). This substantial association underscores the need for careful consideration when deciding whether to use surgical drains in this patient population. The statistical significance of this factor (p = 0.028) highlights its importance in SSIs risk assessment. Additionally, the presence of diabetes mellitus was identified as a significant predictor, with patients having diabetes being over three times more likely to encounter postoperative infections (OR = 3.194, p = 0.045). This finding emphasises the need for stringent glycemic control and heightened perioperative surveillance in diabetic patients to mitigate the risk of SSIs. An open wound at the time of surgery also stood out as a notable predictor, increasing the risk of SSIs (OR = 3.008, p = 0.012). Surgeons and healthcare providers should exercise caution and consider appropriate wound management strategies in such cases to minimise infection risk. Lastly, the non-prophylactic use of antibiotics was associated with a more than twofold increased risk of SSIs (OR = 2.55, p = 0.031). This finding highlights the critical role of prophylactic antibiotic administration in reducing the incidence of postoperative infections.
Several limitations should be acknowledged in our study. Firstly, the research was conducted in a single centre, which may limit the generalizability of our findings to other healthcare settings. Secondly, the retrospective nature of the study introduced potential recall and information bias. Thirdly, the sample size, although adequate for our analyses, may not capture fewer common predictors. Additionally, unmeasured confounders could influence the observed associations. Lastly, the study primarily focused on surgical factors, and other variables such as immunological status were not included, potentially affecting the comprehensiveness of the analysis.
5 CONCLUSIONS
The placement of surgical drains, the presence of diabetes mellitus, open wounds and non-prophylactic antibiotic use are identified as significant predictors for surgical site infections following TPH. In clinical practice, prompt and accurate identification of these factors is imperative. Proactive prevention strategies are essential to substantially reduce the incidence of surgical site infections, thereby enhancing patient outcomes.
CONFLICT OF INTEREST STATEMENT
The authors declare that they have no competing interests.
ETHICS STATEMENT
Ethics Committee of the Second Hospital of Yinzhou District.
INFORMED CONSENT
Written informed consent for publication was obtained from all patients and their families included in this retrospective analysis.
Open Research
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available from the corresponding author upon reasonable request.
