Moderate to severe leukocytosis with vasopressor use is associated with increased mortality in trauma patients

Association between preoperative white blood cell counts and thirty-day surgical mortality after craniotomy in adult intracranial tumor patients

Objective

White blood cell (WBC) counts has been identified as a prognostic biomarker which frequently predict adverse outcomes and mortality risk in various conditions. However, evidence for the association between WBC counts and short-term outcomes after intracranial tumor resection remains limited. This study aimed to explore associations between preoperative WBC counts and thirty-day surgical mortality after craniotomy in adult intracranial tumor patients.

Methods

This retrospective cohort study performed secondary analysis of 18,049 intracranial tumor craniotomy patients from the ACS NSQIP database (2012-2015). The major exposure and outcome were preoperative WBC counts and thirty-day surgical mortality, respectively. Cox regression modeling assessed the linear association between them. Non-linear associations between them were evaluated by conducting smooth curve fitting using an additive Cox proportional hazard model in conjunction with segmented linear regression modeling. Subgroup analysis and interaction testing assessed effect modification. Sensitivity analysis evaluated result robustness.

Results

The total thirty-day surgical mortality after craniotomy was 2.49% (450/18,049). The mean of preoperative WBC counts was 9.501 ± 4.402 × 10^9/L. Fully adjusted model shows that elevated preoperative WBC counts was independently associated with increased thirty-day surgical mortality (HR = 1.057, 95%CI: 1.040, 1.076). Further analysis revealed a non-linear association between them: below a WBC threshold of 13.6 × 10^9/L, higher WBC counts elevated thirty-day mortality (HR = 1.117; 95%CI: 1.077, 1.158), while risk plateaued and no significant mortality rise occurred above this level (HR = 1.015, 95%CI: 0.982, 1.050). Steroid usage status has a significant effect modification on the WBC-mortality association (P for interaction = 0.002). The non-linear WBC-mortality association was only present for non-steroid users (HR = 1.158, 95%CI: 1.108, 1.210) but not steroid users (HR = 1.009, 95%CI: 0.966, 1.055). The sensitivity analysis confirmed the result robustness.

Conclusion

Elevated preoperative WBC counts were independently and non-linearly associated with an increased risk of thirty-day surgical mortality in adult non-steroid use patients undergoing craniotomy for intracranial tumors. As a convenient predictor, preoperative WBC data allows improved risk profiling and personalized management in adult intracranial tumor patients.

Etiologies of Extreme Leukocytosis

OBJECTIVE

The objective of this study was to determine the etiologies and co-morbidities associated with extreme leukocytosis, which is characterized by a white blood cell (WBC) count ≥ 35 × 10⁹ leukocytes/L.  Method: Retrospective chart review was conducted for all patients, aged 18 years and older, admitted to the internal medicine department between 2015 and 2021 with an elevated WBC count ≥ 35 × 10⁹ leukocytes/L within the first 24 hours of admission.  Results: Eighty patients were identified to have WBC count ≥ 35 × 10⁹ leukocytes/L. The overall mortality was 16% and increased to 30% in those presenting with shock. Mortality increased from 2.8% in patients with WBC count in the range of 35-39.9 × 10⁹ leukocytes/L to 33% in those with WBC count in the range of 40-50 × 10⁹ leukocytes/L. There was no correlation with underlying co-morbidities or age. Pneumonia was the most common infection (38%), followed by UTI or pyelonephritis (28%) and abscesses (10%). There was no predominant organism responsible for these infections. The most common etiology for WBC count between 35-39.9 × 10⁹ leukocytes/L and 40-50 × 10⁹ leukocytes/L was infections, while malignancies (especially chronic lymphocytic leukemia) were more common with WBC count > 50 × 10⁹ leukocytes/L.  Conclusion: For WBC counts in the range of 35-50 × 10⁹ leukocytes/L, infections were the main reason for admission to the internal medicine department. Mortality increased from 2.8% to 33% as WBC counts increased from 35-39.9 × 10⁹ leukocytes/L to 40-50 × 10⁹ leukocytes/L. Overall, mortality for all WBC counts ≥ 35 × 10⁹ leukocytes/L was 16%. The most common infections were pneumonia, followed by UTI or pyelonephritis and abscesses. The underlying risk factors did not correlate with WBC counts or mortality.

Shift of Neutrophils From Blood to Bone Marrow Upon Extensive Experimental Trauma Surgery

Introduction

Extensive trauma surgery evokes an immediate cellular immune response including altered circulatory neutrophil numbers. The concurrent bone marrow (BM) response however is currently unclear. We hypothesize that these BM changes include (1) a relative reduction of the bone marrow neutrophil fraction and (2) increasing heterogeneity of the bone marrow neutrophil pool due to (3) the appearance of aged/returning neutrophils from circulation into the BM-compartment.

Materials and Methods

Eight pigs were included in a standardized extensive trauma surgery model. Blood and bone marrow samples were collected at baseline and after 3 hours of ongoing trauma surgery. Leukocyte and subtype counts and cell surface receptor expression levels were studied by flow cytometry.

Results

All animals survived the interventions. A significant drop in circulating neutrophil counts from 9.3 to 3.2x10⁶ cells/ml (P=0.001) occurred after intervention, whereas circulatory neutrophil cell surface expression of CD11b increased. The concurrent bone marrow response included an increase of the BM neutrophil fraction from 63 ± 3 to 71 ± 3 percent (P<0.05). Simultaneously, the BM neutrophil pool became increasingly mature with a relative increase of a CXCR4^high-neutrophil subtype that was virtually absent at baseline.

Conclusion

The current study shows a shift in composition of the BM neutrophil pool during extensive trauma surgery that was associated with a relatively circulatory neutropenia. More specifically, under these conditions BM neutrophils were more mature than under homeostatic conditions and a CXCR4^high-neutrophil subset became overrepresented possibly reflecting remigration of aged neutrophils to the BM. These findings may contribute to the development of novel interventions aimed to modify the trauma-induced immune response in the BM.