Can we improve early identification of neonatal late-onset sepsis? A validated prediction model

DEVELOPMENT AND VALIDATION OF A MODEL FOR PREDICTION OF SEPTIC SHOCK IN NEONATES WITH SEPSIS

ABSTRACT

Purpose: This study aimed to develop and validate a model for prediction of septic shock in neonates with sepsis. Materials and methods: This retrospective study included early-onset septic neonates in the Renmin Hospital of Wuhan University between January 2017 and June 2021. The neonates were divided into the training set and the validation set in a ratio of 7:3 and further categorized into septic shock group and none-shock group according to presence or absence of shock symptoms. Results: A total of 406 septic neonates were enrolled, including 217 in septic shock group. Sex (odds ratio [OR] = 0.092, 95% confidence interval [CI]: 0.012 to 0.683, P = 0.020), C-reactive protein at 6 h (OR = 8.475, 95% CI: 3.154 to 22.774, P < 0.001), serum amyloid A at 6 h (OR = 1.179, 95% CI: 1.094 to 1.269, P < 0.01), white blood cells at 6 h (OR = 0.173, 95% CI: 0.092 to 0.326, P < 0.001), platelets at 6 h (OR = 0.985, 95% CI: 0.975 to 0.995, P < 0.001), and Ca 2+ at 6 h (OR = 1.44 × 10 11 , 95% CI: 2.70 × 10 6 to 7.70 × 10 15 , P < 0.001) were identified as independent risk factors for septic shock and were further included in the nomogram. The areas under the receiver operator characteristic curve were 0.873 and 0.920 in training and validation sets, respectively. Conclusions: A predictive model for early diagnosis of septic shock in neonates was developed and initially validated in this study, allowing for timely intervention.

Prediction model for early diagnosis of late-onset sepsis in preterm newborns

AİM

Late-onset neonatal sepsis has a high mortality rate in premature infants. To date, no single test in the evaluation of neonatal sepsis has been demonstrated to be both sensitive and specific enough to assist in timely decision making. The aim of our study is to develop a predictive model that can be applied to all premature babies, using clinical and laboratory findings in premature babies, to recognize late-onset neonatal sepsis.

STUDY DESİGN

65 premature patients diagnosed with culture-proven late-onset neonatal sepsis and hospitalized in Dr. Behcet Uz Pediatric Diseases and Surgery Training and Research Hospital neonatal intensive care unit between January 2018 and December 2020, and 65 premature newborns of similar age and gender who did not have sepsis were included in the study retrospectively.

RESULTS

In our study, feeding difficulties, worsening in clinical appearance and fever were found to be significant among clinical findings, while thrombocytopenia and high C-reactive protein among laboratory findings are the strongest data supporting late-onset neonatal sepsis. In multiple regression analysis, thrombocytopenia, mean platelet volume, C-reactive protein, lymphocyte count and feeding difficulties had the highest odds ratio (p < 0.05). By converting these data into a scoring system, a nomogram was created that can be easily used by all clinicians.

CONCLUSION

In our study, we developed a scoring system that can be easily applied to all premature patients by evaluating the clinical and laboratory findings in late-onset neonatal sepsis. We think that it will help in recognizing late-onset neonatal sepsis and strengthening the treatment decision. Predicting the individual probability of sepsis in preterm newborns may provide benefits for uninfected newborns to be exposed to less antibiotics, not to be separated from mother and baby, and to reduce healthcare system expenditures. The nomogram can be used to assess the likelihood of sepsis and guide treatment decision.

Meta-analysis of the role of neutrophil to lymphocyte ratio in neonatal sepsis

INTRODUCTION

The neutrophil to lymphocyte ratio (NLR), an inflammatory biomarker, measures innate-adaptive immune system balance. In this systematic review and meta-analysis, we aim to analyze the current literature to evaluate the diagnostic role of NLR in neonatal sepsis.

METHODS

PubMed, Web of Science, and Scopus were used to conduct a systematic search for relevant publications published before May 14, 2022.

RESULTS

Thirty studies, including 2328 neonates with sepsis and 1800 neonates in the control group, were included in our meta-analysis. The results indicated that NLR is higher in neonates with sepsis compared to healthy controls (SMD = 1.81, 95% CI = 1.14-2.48, P-value < 0.001) in either prospective (SMD = 2.38, 95% CI = 1.40-3.35, P-value < 0.001) or retrospective studies (SMD = 0.87, 95% CI = 0.63-1.12, P-value < 0.001) with a pooled sensitivity of 79% (95% CI = 62-90%), and a pooled specificity of 91% (95% CI = 73-97%). Also, we found that NLR is higher in neonates with sepsis compared to those who were suspected of sepsis but eventually had negative blood cultures (SMD =1.99, 95% CI = 0.76-3.22, P-value = 0.002) with a pooled sensitivity of 0.79% (95% CI = 0.69-0.86%), and a pooled specificity of 73% (95% CI = 54-85%). In addition, neonates with sepsis had elevated levels of NLR compared to other ICU admitted neonates (SMD = 0.73, 95% CI = 0.63-0.84, P < 0.001). The pooled sensitivity was 0.65 (95% CI, 0.55-0.80), and the pooled specificity was 0.80 (95% CI, 0.68-0.88).

CONCLUSION

Our findings support NLR as a promising biomarker that can be readily integrated into clinical settings to aid in diagnosing neonatal sepsis. As evidenced by our results, restoring balance to the innate and adaptive immune system may serve as attractive therapeutic targets. Theoretically, a reduction in NLR values could be used to measure therapeutic efficacy, reflecting the restoration of balance within these systems.

Can We Estimate Late-Onset Sepsis by Serial Methemoglobin Levels? An Observational Study in Preterm Neonates

Objective: To assess serial methemoglobin (MetHb) levels in preterm infants as a possible diagnostic method for late-onset sepsis (LOS). Methods: Preterm infants were assigned into two groups: those with culture-proven LOS and controls. Serial MetHb levels were measured. Results: The MetHb values of the LOS group were found to be significantly increased (p < 0.001). The cutoff value for the detection of LOS was calculated as MetHb > 1.75%, optimized for a sensitivity of 81.9% and specificity of 90%. After antimicrobial therapy, MetHb values were found to decrease significantly (p < 0.001). MetHb had an AUC of 0.810 for mortality using the calculated cutoff of >2% (p < 0.005). Conclusions: MetHb levels increase at the onset of LOS and decrease following treatment. MetHb can be added to other sepsis biomarkers as a rapid infectious process indicator for preterm neonates. MetHb > 2% is associated with LOS mortality.

The Neutrophil-to-Lymphocyte Ratio (NLR) Can Predict Sepsis's Presence and Severity in Malnourished Infants-A Single Center Experience

Sepsis represents one of the leading causes of death in newborns and infants, and prompt diagnosis is essential for achieving favorable outcomes. Regarding malnourished children with concurrent infection, most studies have focused, besides blood culture, on C-reactive protein and procalcitonin. Because malnutrition has a deleterious effect on cellular immune competence, the present study characterized the acute-phase response, including hematological indices, in response to sepsis. Among the examined laboratory biomarkers, procalcitonin and neutrophil-to-lymphocyte ratio were the most accurate discriminators between sepsis patients and those with bacterial infection. Moreover, these two parameters showed a gradual increase between sepsis, severe sepsis, and septic shock patients (p < 0.001). Subgroup analysis of the sepsis group revealed positive correlations of NLR with prolonged ICU stay (<0.001), acute organ dysfunction (0.038), mechanical ventilation (<0.001), and fatality (<0.001). In summary, our results suggest that the neutrophil-to-lymphocyte ratio can be used as an auxiliary diagnostic index in discriminating the presence and severity of bacterial sepsis in malnourished infants.

Comparison of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio for the diagnosis of neonatal sepsis: a systematic review and meta-analysis

PURPOSE

To compare the performance of Neutrophil-to-Lymphocyte Ratio (NLR) with that of Platelet-to-Lymphocyte Ratio (PLR) in diagnosing neonatal sepsis (NS).

METHODS

PubMed and Embase were searched for relevant studies from the inception of the databases to May, 2022. The pooled sensitivity (SEN), specificity (SPE), and area under the receiver operator characteristic curve (AUC) were measured.

RESULTS

Thirteen studies involving 2610 participants were included. The SEN, SPE, and AUC of NLR were 0.76 (95%CI: 0.61-0.87), 0.82 (95%CI: 0.68-0.91), and 0.86 (95%CI: 0.83-0.89), respectively, and those of PLR were 0.82 (95%CI: 0.63-0.92), 0.80 (95%CI: 0.24-0.98), and 0.87 (95%CI: 0.83-0.89), respectively. Significant heterogeneity was observed among the studies. Subgroup analysis and meta-regression showed that types of sepsis (p = 0.01 for SEN), gold standard (p = 0.03 for SPE), and pre-set threshold (p<0.05 for SPE) might be the sources of heterogeneity for NLR, whereas the pre-set threshold (p<0.05 for SPE) might be the source of heterogeneity for PLR.

CONCLUSIONS

NLR and PLR would be of great accuracy for the diagnosis of NS, and the two indicators have similar diagnostic performance. However, the overall risk of bias was high, and significant heterogeneity was identified among the included studies. The results of this study should be interpreted prudently, and the normal or cut-off values and the type of sepsis should be considered. More prospective studies are needed to further support the clinical application of these findings.

Evaluation of Haematological Parameters and Uric Acid in the Diagnosis of Late Onset Neonatal Sepsis

Introduction A number of parameters studied in a whole blood count can be helpful in the diagnosis of neonatal sepsis. The platelet/lymphocyte ratio (PLR) is a systemic inflammatory marker in early sepsis and has been used as a diagnostic indicator in cardiovascular events and cancer. Being one of the major antioxidants in human biological fluids, serum uric acid is responsible for neutralising free radicals. The red cell distribution width/platelet ratio (RPR) is a diagnostic marker in adult inflammatory diseases. The objective of our study is to investigate the relationship of late neonatal sepsis with whole blood count parameters and serum uric acid levels. Materials and methods Newborns older than postnatal three days who had clinical and laboratory findings of sepsis were included in the study. The study included 140 newborns who were divided into three groups, 53 in the culture-proven late sepsis group, 47 in the clinical sepsis group, and 40 in the healthy control group. The whole blood count parameters and serum uric acid levels were examined in both the clinical sepsis and proven sepsis patients at the time when they were diagnosed with sepsis. Results The birth week was significantly lower in the evidenced and clinical sepsis patients compared to the healthy control group. Development of late sepsis was significantly higher in the male gender than in healthy controls. Serum uric acid levels were significantly higher in proven or clinical sepsis than in healthy controls. The level of serum uric acid (3.77±1.6) in proven sepsis was significantly higher than the control group (2.83±1.1). The uric acid level had an area under the curve (AUC) 0.552-0.717, 35% sensitivity, 95% specificity, 94.6% positive predictive value (PPV), and 36.9% negative predictive value (NPV) in the diagnosis of proven and clinical late sepsis. Neutrophil/lymphocyte ratio (NLR) was significantly higher in proven sepsis than in healthy newborns and was higher in the clinical sepsis group than in the proven sepsis group (p: 0.002). While the mean eosinophil value was 618.5±472.1 in proven sepsis, it was 549.3±294.9 in the control group and there was a statistically significant difference between the two groups (p: 0.036). Conclusion In late-onset neonatal sepsis, the NLR level was higher, and the eosinophil level was lower in the clinical sepsis patients than in healthy newborns. We believe that a higher level of serum uric acid in sepsis is effective in the early diagnosis of patients who also had other clinical findings of sepsis.

Carboxyhemoglobin Levels in Preterm Neonatal Late-Onset Sepsis: to Predict or not to Predict

Background

In this study, we aimed to evaluate carboxyhemoglobin (COHb) levels in diagnosing late-onset sepsis (LOS) in preterm neonates.

Methods

The records of culture-positive LOS in preterm neonates hospitalized in NICU from January 2017 to July 2022 were reviewed. COHb levels, C-reactive protein, procalcitonin, and neutrophil to lymphocyte ratio of septic preterm infants were compared to controls. In addition, serial COHb levels measured within six hours before or 24h after blood culture sampling, three to seven days prior, and three to five days after starting antimicrobial therapy were retrieved from patient records.

Results

The study included 77 blood-culture-positive preterm infants and 77 non-septic controls. During the LOS episode, the COHb values were found to be significantly increased (median: 1.8, IQR: 1.4-2.5) when compared to the control group (median: 1.2, IQR: 0.8-1.6) (p < 0.001). ROC analysis yielded an AUC of 0.714 for COHb (95% CI: 0.631-0.796, p<0.001). At an optimal cut-off of >1.5%, the test's sensitivity was 64.94%, the specificity was 72.73%, the positive predictive value was 70.42%, and the negative predictive value was 67.47%. LOS led to a dramatic rise followed by a decrease after the initiation of the antimicrobial therapy [1.8 (1.4-2.5)] vs. [1.45 (0.2-4)] p<0.001.

Conclusion

COHb levels increased at the beginning of LOS, decreasing in response to antibiotics. When used in conjunction with other sepsis biomarkers, the variation of COHb can be important in evaluating late-onset sepsis episodes in preterm infants.

Artificial and human intelligence for early identification of neonatal sepsis

Artificial intelligence may have a role in the early detection of sepsis in neonates. Machine learning can identify patterns that predict high or increasing risk for clinical deterioration from a sepsis-like illness. In developing this potential addition to NICU care, careful consideration should be given to the data and methods used to develop, validate, and evaluate prediction models. When an AI system alerts clinicians to a change in a patient's condition that warrants a bedside evaluation, human intelligence and experience come into play to determine an appropriate course of action: evaluate and treat or wait and watch closely. With intelligently developed, validated, and implemented AI sepsis systems, both clinicians and patients stand to benefit. IMPACT: This narrative review highlights the application of AI in neonatal sepsis prediction. It describes issues in clinical prediction model development specific to this population. This article reviews the methods, considerations, and literature on neonatal sepsis model development and validation. Challenges of AI technology and potential barriers to using sepsis AI systems in the NICU are discussed.

Accuracy of the neutrophil-to-lymphocyte ratio for the diagnosis of neonatal sepsis: a systematic review and meta-analysis

OBJECTIVES

The purpose of this study was systematically and quantitatively to assess the value of the neutrophil-to-lymphocyte ratio (NLR) for the diagnosis of neonatal sepsis by systematic review and meta-analysis.

DESIGN

Systematic review and meta-analysis.

METHODS

Eight major databases, including The Cochrane, PubMed, Embase, Web of Science, CNKI, Wanfang, China Biomedical Literature Database and VIP Database, were systematically searched for NLR diagnoses of neonatal sepsis from inception to June 2022. Two investigators independently conducted the literature search, screening, data extraction and quality evaluation with the Quality Assessment of Diagnostic Accuracy Studies-2 checklist. Statistical analysis was performed using Review Manager V.5.3, Stata V.16.0, R (V.3.6.0) and Meta-DISC V.1.4.

RESULTS

A total of 14 studies comprising 1499 newborns were included in this meta-analysis. With a cut-off value ranging from 0.1 to 9.4, the pooled sensitivity of the NLR in the diagnosis of neonatal sepsis was 0.74 (95% CI: 0.61 to 0.83), the pooled specificity was 0.88 (95% CI: 0.73 to 0.95), the positive likelihood ratio (LR+) was 6.35 (95% CI: 2.6 to 15.47), the negative likelihood ratio (LR-) was 0.30 (95% CI: 0.19 to 0.46), the diagnostic OR (DOR) was 12.88 (95% CI: 4.47 to 37.08), area under the curve (AUC) was 0.87 (95% CI: 0.84 to 0.89). In the subgroup analysis of early-onset neonatal sepsis, the pooled sensitivity was 0.75 (95% CI: 0.47 to 0.91), the pooled specificity was 0.99 (95% CI: 0.88 to 1.00), the LR+ was 63.3 (95% CI: 5.7 to 696.8), the LR- was 0.26 (95% CI: 0.10 to 0.63), the DOR was 247 (95% CI: 16 to 3785) and the AUC was 0.97 (95% CI: 0.95 to 0.98).

CONCLUSIONS

Our findings suggest that the NLR is a helpful indicator for the diagnosis of early neonatal sepsis, but it still needs to be combined with other laboratory tests and specific clinical manifestations.

Development of a Novel Assessment Tool and Code Sepsis Checklist for Neonatal Late-Onset Sepsis

BACKGROUND

Accurate diagnosis and timely management of neonatal late-onset sepsis (nLOS) have been less well-studied than those of early-onset sepsis. We noticed a delay in nLOS detection and management in our neonatal intensive care unit.

PURPOSE

To develop an assessment tool to aid in the recognition and reporting of nLOS and to standardize the management process once sepsis is recognized.

METHODS

The Plan-Do-Study-Act (PDSA) improvement model provided the framework for interventions for our antibiotic stewardship program, including the aims of this project. A literature review was performed to evaluate tools and other literature available to guide the evaluation and management of suspected sepsis. A quality improvement project was initiated to develop tools for the detection and management of nLOS.

RESULTS

An nLOS assessment tool to help identify neonates at risk for nLOS and a Code Sepsis checklist to standardize the process of evaluation and management of nLOS were developed. The guiding principles of this tool development were empowerment of nurses to initiate the assessment process, clarification of team roles, and removal of barriers to appropriate antibiotic administration.

IMPLICATIONS FOR PRACTICE

Useful and practical tools valued by nursing and the multidisciplinary team may facilitate timely identification and treatment of infants with nLOS.

IMPLICATIONS FOR RESEARCH

Future directions include validation of the nLOS assessment tool and the Code Sepsis checklist as well as ensuring the reliability of the tool to improve detection of nLOS and to reduce time to administer antibiotics in cases of nLOS.

The Utility of Peripheral Blood Leucocyte Ratios as Biomarkers in Neonatal Sepsis: A Systematic Review and Meta-Analysis

BACKGROUND

Early stage diagnosis of neonatal sepsis (NS) remains a major roadblock due to non-specific symptoms and the absence of precise laboratory index tests. The full blood count is a relatively cheap, universal, and rapid diagnostic test.

METHOD

This study assessed the diagnostic accuracies of immature-to-total neutrophil ratio (ITR), immature-to-mature neutrophil ratio (IMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) used in the diagnosis of NS. Included studies were retrieved by searching four major databases and relevant references, and reviewed based on the inclusion/exclusion criteria. Pooled sensitivities and specificities were calculated, I ² was utilized to test for heterogeneity, and the source was investigated via meta-regression analysis.

RESULTS

Finally, 38 studies passed the eligibility criteria. A total of thirty-one studies (6,221 neonates) included data on the ITR, eight studies (1,230 neonates) included data on the IMR, seven studies (751 neonates) included data on the NLR, and two studies (283 neonates) included data on the PLR. The summary sensitivity estimates with 95% confidence interval (CI) for the ITR, IMR, NLR, and PLR tests were, respectively, 0.74 (95% CI: 0.66-0.80), 0.74 (95% CI: 0.54-0.88), 0.73 (95% CI: 0.68-0.78), and 0.81 (95% CI: 0.55-1.00). The summary specificity values for the ITR, IMR, NLR, and PLR tests were 0.83 (95% CI: 0.77-0.87), 0.89 (95% CI: 0.80-0.94), 0.69 (95% CI: 0.57-0.79), and 0.93 (95% CI: 0.81-1.00), respectively. The area under the summary receiver operating characteristic curves for the ITR, IMR, and NLR tests were 0.85 (95% CI: 0.82-0.88), 0.91 (95% CI: 0.88-0.93), and 0.75 (95% CI: 0.71-0.79). The PLR could not be evaluated because only two studies included pertinent data.

CONCLUSION

The NLR test might not be sufficiently accurate in precisely diagnosing NS. The ITR and IMR tests alone can improve the accuracy of NS diagnosis, but the marked heterogeneity and the limited number of studies prevented us from reaching any definitive conclusions. Thus, further studies are warranted to validate these findings.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021247850].

Prediction modelling in the early detection of neonatal sepsis

BACKGROUND

Prediction modelling can greatly assist the health-care professionals in the management of diseases, thus sparking interest in neonatal sepsis diagnosis. The main objective of the study was to provide a complete picture of performance of prediction models for early detection of neonatal sepsis.

METHODS

PubMed, Scopus, CINAHL databases were searched and articles which used various prediction modelling measures for the early detection of neonatal sepsis were comprehended. Data extraction was carried out based on Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies checklist. Extricate data consisted of objective, study design, patient characteristics, type of statistical model, predictors, outcome, sample size and location. Prediction model Risk of Bias Assessment Tool was applied to gauge the risk of bias of the articles.

RESULTS

An aggregate of ten studies were included in the review among which eight studies had applied logistic regression to build a prediction model, while the remaining two had applied artificial intelligence. Potential predictors like neonatal fever, birth weight, foetal morbidity and gender, cervicovaginitis and maternal age were identified for the early detection of neonatal sepsis. Moreover, birth weight, endotracheal intubation, thyroid hypofunction and umbilical venous catheter were promising factors for predicting late-onset sepsis; while gestational age, intrapartum temperature and antibiotics treatment were utilised as budding prognosticators for early-onset sepsis detection.

CONCLUSION

Prediction modelling approaches were able to recognise promising maternal, neonatal and laboratory predictors in the rapid detection of early and late neonatal sepsis and thus, can be considered as a novel way for clinician decision-making towards the disease diagnosis if not used alone, in the years to come.

Antibiotic Discontinuation 24 h After Neonatal Late-Onset Sepsis Work-Up-A Validated Decision Tree Model

Objectives: Neonatal late-onset sepsis work-up is a frequent occurrence in every neonatal department. Blood cultures are the diagnostic gold standard, however, a negative culture prior to 48-72 h is often considered insufficient to exclude sepsis. We aimed to develop a decision tree which would enable exclusion of late-onset sepsis within 24 h using clinical and laboratory variables. Study Design: Infants evaluated for late-onset sepsis during the years 2016-2019, without major malformations, in a tertiary neonatal center were eligible for inclusion. Blood cultures and clinical and laboratory data were extracted at 0 and 24 h after sepsis work-up. Infants with bacteriologically confirmed late-onset sepsis were compared to matched control infants. Univariate logistic regression identified potential risk factors. A decision tree based on Chi-square automatic interaction detection methodology was developed and validated. Results: The study cohort was divided to a development cohort (105 patients) and a validation cohort (60 patients). At 24 h after initial evaluation, the best variables to identify sepsis were C-reactive protein > 0.75 mg/dl, neutrophil-to-lymphocyte ratio > 1.5 and sick-appearance at 24 h. Use of these 3 variables together with blood culture status at 24 h, enabled identification of all infants that eventually developed sepsis through the decision tree model. Our decision tree has an area under the receiver operating characteristic curve of 0.94 (95% CI: 0.90-0.98). Conclusions: In non-sick appearing infants with a negative blood culture at 24 h and normal laboratory values, sepsis is highly unlikely and discontinuing antibiotics after 24 h is a viable option.

Puzzling paracoccidioidomycosis: Factors associated with the severity of Paracoccidioides lutzii infections

OBJECTIVES

Historically, the Brazilian Central-West region has had high numbers of paracoccidioidomycosis (PCM) cases caused by the dimorphic fungus Paracoccidioides lutzii.

METHODS

This epidemiological, observational, analytical, cross-sectional study was performed to investigate the clinical and laboratory data of 44 PCM patients with a culture-proven P. lutzii infection. All patients were referred to the Systemic Mycosis Center, Júlio Muller University Hospital, Cuiabá, Brazil, during January 2017 to March 2020. The neutrophil to lymphocyte ratio (NLR) was calculated and dichotomized by its median value to include in the identification of factors associated with severity.

RESULTS

At admission, 13 (31.7%) patients showed the disseminated multifocal chronic form of PCM and 16 (36.4%) patients met the clinical severity criteria. Treatment prescribed on admission did not follow the recommendations of the Brazilian Guideline for the Clinical Management of Paracoccidioidomycosis in 26% of the severe PCM cases (prevalence ratio 0.26, 95% confidence interval 0.14-0.49; P < 0.0001). Patients with severe PCM had a higher NLR that was greater than the median (≥4.11).

CONCLUSIONS

The NLR biomarker complements the criteria for PCM severity. Applying the low-cost NLR test can greatly increase the diagnostic sensitivity when screening patients for PCM and contribute to better control of the disease, management of complications, and therapeutic strategies.

Clinical and vital sign changes associated with late-onset sepsis in very low birth weight infants at 3 NICUs

BACKGROUND

In premature infants, clinical changes frequently occur due to sepsis or non-infectious conditions, and distinguishing between these is challenging. Baseline risk factors, vital signs, and clinical signs guide decisions to culture and start antibiotics. We sought to compare heart rate (HR) and oxygenation (SpO2) patterns as well as baseline variables and clinical signs prompting sepsis work-ups ultimately determined to be late-onset sepsis (LOS) and sepsis ruled out (SRO).

METHODS

At three NICUs, we reviewed records of very low birth weight (VLBW) infants around their first sepsis work-up diagnosed as LOS or SRO. Clinical signs prompting the evaluation were determined from clinician documentation. HR-SpO2 data, when available, were analyzed for mean, standard deviation, skewness, kurtosis, and cross-correlation. We used LASSO and logistic regression to assess variable importance and associations with LOS compared to SRO.

RESULTS

We analyzed sepsis work-ups in 408 infants (173 LOS, 235 SRO). Compared to infants with SRO, those with LOS were of lower GA and BW, and more likely to have a central catheter and mechanical ventilation. Clinical signs cited more often in LOS included hypotension, acidosis, abdominal distension, lethargy, oliguria, and abnormal CBC or CRP(p <  0.05). HR-SpO2 data were available in 266 events. Cross-correlation HR-SpO2 before the event was associated with LOS after adjusting for GA, BW, and postnatal age. A model combining baseline, clinical and HR-SpO2 variables had AUC 0.821.

CONCLUSION

In VLBW infants at 3-NICUs, we describe the baseline, clinical, and HR-SpO2 variables associated with LOS versus SRO.