Sex-Based Differences in Depth of Soft Tissue at the Proximal Tibia Intraosseous Catheter Insertion Site

Background Intraosseous (IO) catheters are commonly used to rapidly obtain vascular access for critically-ill patients in the emergency department (ED). Although the proximal tibia (PT) is a standard IO insertion site for adult subjects, little is known about sex-based variation in the proper depth of insertion. Methods A retrospective cohort study was performed, utilizing CT scans obtained from DMC over a ten-year period (2009-2018) to estimate soft tissue depth overlying the recommended PT-IO insertion site. Depths of soft tissue from skin surface to bone surface (Measurement A) and from skin surface to the opposite bony cortex (Measurement B) were measured using standard radiologic software. Results A total of 217 subjects were enrolled, including 106 (48.9%) males. Body mass index (BMI) was not significantly different between sexes (p=0.188). Measurement A for females (x̄=21.65 mm, σ=8.17) was significantly greater than for males (x̄=13.64 mm, σ=5.52) (p\u3c0.0001). Measurement A was \u3e25-mm in 5.7% of males and 27.0% of females (p\u3c0.001). Measurement B was \u3c45-mm in 24.5% of males and 21.6% of females. Conclusion Our results suggest that sex-based differences exist in soft tissue depth at the PT site, despite similar BMI values. Since common IO needle lengths are 25-mm and 45-mm, these results have profound implications. The 25-mm needle would have been too short for more than one-fourth of female subjects. However, a 45-mm catheter would have been too long for almost one-fourth of all subjects. Further study is needed to determine whether this sex difference exists in a larger cohort of patients

The Relationship Between Delayed Vasopressor Usage and Mortality in Sepsis

Introduction Delayed vasopressor initiation can occur with septic patients who arrive to the emergency department (ED) hemodynamically stable but decompensate later in their ED or hospital course. The relationship between delayed vasopressor initiation and mortality among septic patients is not well understood. Methods We performed a retrospective review of ED visits for sepsis by adult patients at two urban institutions from January 2010 - March 2015. Included patients were diagnosed with sepsis in the ED and had initial (\u3c 3 hours) lactate in the “pre-shock” range of 2-4 mmol/L. Patients who received delayed (\u3e3- but \u3c 48-hours following ED arrival) vasopressors were compared to those who did not. Data were collected on patient demographics, vital signs, laboratory tests, medications given, length of ED and hospital stay, and mechanical ventilation status. Descriptive data analysis and group-wise comparisons were performed, including logistic regression. Results A total of 407 patients were included, with a mean age 65 years (SD 17.3). Mortality rate was 31% (61/197) among patients receiving delayed vasopressors [vs. 9.5% (20/210) for patients receiving no vasopressors (p=.0001)], and 38% (54) for those receiving mechanical ventilation [vs. 10% (27) among non-intubated patients]. Vasopressor usage (p=.0080; OR 2.32) and mechanical ventilation (p=.0001; OR 3.75) were both significant predictors of mortality. The majority (58%) of patients receiving delayed vasopressors were also mechanically ventilated. Median survival from time of ED arrival for those who died was 96 hours (Q1, Q3: 48, 240). Other variables, such as MAP, age, sex, lactate, and creatinine did not appear to predict mortality. Conclusions In this data set, we found that delayed initiation of vasopressors and mechanical ventilation were both independently associated with increased mortality for “pre-shock” septic patients. A significant proportion of those patients who received delayed vasopressors also received mechanical ventilation. Further study is needed, including larger data sets