ABSTRACT
The utility of carotid artery Doppler flow velocity (CADFV) over mortality is not well known. This study investigated the utility of bedside ultrasound in assessing volume status and predicting mortality in patients with septic shock with CADFV, the inferior vena cava collapse index, and the central venous pressure (CVP). This prospective observational study included adults admitted to the ED with septic shock, defined by hypotension (SBP < 90 mmHg or MAP < 65 mmHg) and evidence of end-organ hypoperfusion. Patient demographics, CVP, CADFV, inferior vena cava (IVC) diameter, inferior vena cava collapsibility index (IVCCI), and outcomes were recorded. Measurements are compared in terms of mortality. The mean age was 67 years, with a 57% mortality rate. ROC analysis revealed that CADFV predicted mortality with a sensitivity of 72% and a specificity of 68% at a cutoff of 50 cm/s. The IVCCI had 93% sensitivity and 85% specificity at a cutoff of 54.5%. The CVP had 61% sensitivity and 71% specificity at a cutoff of 1.5 mm H₂O. The mean IVCCI was 59%, and the mean CVP was 2.4 mmH₂O. The mean IVCCI was 59%, and the mean CVP was 2.4 mmH₂O. The deceased patients had a mean IVCCI of 63% and a mean CVP of 1.62 mmH₂O, whereas discharged patients had a mean IVCCI of 55% and a mean CVP of 3.45 mmH₂O. CADFV, IVCCI, and CVP can be used in evaluating the volume status and predicting mortality in septic shock. These noninvasive measures provide alternatives to invasive methods and facilitate timely intervention in emergency care.
KEYWORDS: Bedside ultrasound, carotid doppler flow velocity, volume assessment, emergency medicine, septic shock
1. Introduction
Septic shock is a critical condition characterized by inadequate oxygen delivery to tissues, leading to cellular and tissue hypoxia [1]. Despite significant advancements in emergency and critical care, septic shock remains a major cause of morbidity and mortality worldwide, especially in intensive care units (ICU). Early recognition of septic shock in the emergency department and timely intervention are pivotal for preventing multiorgan failure and death [2,3].
Prompt assessment of intravascular volume status and volume responsiveness is a cornerstone in the management of septic shock, particularly septic shock, and traditional techniques, such as central venous pressure (CVP) measurement, have been widely used. However, these methods are invasive, time-consuming, and may not always provide reliable results for guiding fluid therapy [4,5]. With the advent of bedside ultrasonography, a fast, noninvasive, and accessible method, dynamic assessment of hemodynamic parameters has transformed the evaluation of critically ill patients [6,7].
Bedside ultrasonography, particularly carotid artery Doppler flow velocity (CADFV), inferior vena cava (IVC) diameter, and collapsibility index (IVCCI), are gaining attention for their potential in evaluating volume responsiveness in patients with septic shock [8]. Studies have demonstrated the value of ultrasound in assessing fluid responsiveness in patients with septic shock, highlighting its superior accuracy compared to CVP alone, and providing real-time data that are critical for rapid decision making in emergency settings [9–12].
This study focused on evaluating septic shock patients in the emergency department using a combination of bedside ultrasonography parameters, including CADFV, IVC diameter, IVCCI, and CVP, to determine the volume status and predict mortality outcomes. Our objective was to establish a correlation between these ultrasound-derived parameters and clinical outcomes to provide clinicians with a reliable and accessible method for managing patients with septic shock. Primary aim of the study is measuring carotid artery Doppler flow velocity and assessing its value over predicting mortality. Secondary outcomes are the correlations between CADFV, IVCCI and CVP.
2. Material and methods
2.1. Study design and setting
This prospective observational study was conducted at the Adult ED of Hacettepe University Hospital, Ankara, Turkey. The primary objective was to evaluate the volume status of septic shock patients using bedside ultrasonography to measure the CADFV, IVC diameter, and IVCCI. These parameters are used to predict mortality. This study was approved by the Hacettepe University Ethics Committee (approval number: GO 19/286). The data for this study were collected between 1 March and 1 October 2019.
2.2. Study population and patient selection
The study included adult patients presenting to the ED with clinical manifestations of septic shock, which included symptoms such as hypotension (systolic blood pressure <90 mmHg or mean arterial pressure <65 mmHg), evidence of impaired end-organ perfusion (e.g. altered mental status, decreased urine output <0.5 mL/kg/hour), and clinical signs consistent with a septic shock state. Informed consent is given by all participants of the study. Those who refused to give consent are excluded.
2.3. Inclusion criteria
Patients aged 18 years or over.
Presentation of the ED with clinical signs of septic shock.
Requirement for CVP measurement using a central venous catheter.
Patients who provided informed consent for participation.
2.4. Exclusion criteria
Patients with contraindications to central venous catheterization, such as severe coagulopathy or local infection at the insertion site.
Patients with known severe valvular heart disease can influence hemodynamic measurements and confound the results.
Additionally, patients with incomplete data due to early transfer, refusal to undergo central venous catheterization, or withdrawal from the study were excluded.
2.5. Data collection and measurements
Data collection involved a standardized form documenting patient demographics, medical history, vital signs, CVP, CADFV, ccFT, IVC diameter, IVCCI, diagnosis, clinical outcome (discharge, hospital or ICU admission, and death), and length of stay in the ED and hospital.
2.6. Ultrasound protocol
Ultrasound measurements were performed using a high-resolution Philips EPIQ 5 G ultrasound machine (serial number: US518C0295) equipped with a 5 MHz linear probe and a 2–6 MHz convex probe.
2.6.1. Carotid artery Doppler flow velocity (CADFV)
Patients were positioned supine with the head elevated at a 30-degree angle.
Using the linear probe, the carotid artery was identified in a transverse section at the bifurcation of the ICA and ECA. Doppler examination was performed proximal to the bifurcation to determine the flow velocity, and the corrected carotid flow time (ccFT) was estimated using Hasselbach's formula adjusted for heart rate.
2.6.2. Inferior vena cava (IVC) diameter and collapsibility index (IVCCI)
A convex probe was used to visualize the liver and heart from the subxiphoid window, identifying the IVC and its junction with the right atrium.
IVC diameter was measured approximately 2 cm distal to the cavoatrial junction using M-mode during inspiration and expiration. IVCCI was calculated as follows: IVCCI = (IVC_exp − IVC_insp)/IVC_exp, where IVC_exp is the IVC diameter during expiration and IVC_insp is the diameter during inspiration.
3. Data analysis
Descriptive statistics are presented as mean ± standard deviation (SD) for normally distributed continuous variables and median with interquartile range (IQR) for non-normally distributed variables. Categorical data are presented as frequencies and percentages. The normality of continuous variables was assessed using the Shapiro‒Wilk test, histograms, box plots, and Q‒Q plots. Independent group comparisons were made using the independent t test for normally distributed variables and the Mann‒Whitney U test for variables that did not meet the normality assumption. Relationships between variables were evaluated using the Spearman's correlation coefficient. Receiver operating characteristic (ROC) curve analyzes were performed to determine the optimal cutoff values for predicting mortality using the CADFV, IVCCI, and CVP. The Youden index was used to identify the best balance between the sensitivity and specificity for these cutoff values. A multivariate regression model was employed to determine factors independently associated with the CADFV, adjusting for potential confounders. IBM SPSS Statistics, version 23.0. The statistical significance threshold was set at p < 0.05. No sample size were calculated and all patients compatible with the criteria are included to study in the given time period. Power analyzes showed that we have 0.95 power if we choose effect size as 0.50 that tells us the study has a good power.
4. Results
This study included 51 patients diagnosed with septic shock. Figure 1 presents the flowchart of patients. The mean age of the participants was 67 (SD ± 13) years, with a mortality rate of 57%. The sex distribution was nearly balanced, with 45% female and 55% male participants. Septic shock was the leading cause, representing 88% of the cases. In terms of comorbidities, 45% of the patients had malignancy, 43% had hypertension, 28% had diabetes, 26% had coronary artery disease, and 30% had multiple comorbidities. The discharge rate from the emergency department was 43%, ICU admission was required in 18% of cases, and the overall mortality rate was 57%. Ultrasound measurements showed a mean CADFV of 43 cm/s (±16.7), ranging from 12 to 66 cm/s. The mean ccFT was 382 ms (SD ± 102.2), with values ranging from 134 to 651 ms. The average IVC diameter was 1.8 cm (standard deviation [SD] ± 0.39), while the mean IVCCI was 59% (SD ± 13.6). Table 1 shows the demographics, vital signs, laboratory results, ultrasound measurements, and outcomes of the study cohort.
Figure 1.
Study flow chart.
Table 1.
Patient characteristics, vital signs, laboratory results, ultrasound measurements, and outcomes.
| Characteristic/parameter | Mean (SD)/n (%) | Median (Min–Max) |
|---|---|---|
| Age (years) | 67 (±13) | 21–88 |
| Gender | ||
| Female | 23 (45%) | |
| Male | 28 (55%) | |
| Comorbidities | ||
| Malignancy | 23 (45%) | |
| Hypertension | 22 (43%) | |
| Diabetes mellitus | 14 (28%) | |
| Coronary artery disease | 13 (26%) | |
| Multiple comorbidities (≥2) | 15 (30%) | |
| Outcomes | ||
| Discharged from ED | 6 (%) | |
| Admitted to general ward | 8 (16%) | |
| Admitted to ICU | 9 (18%) | |
| Transferred to Another ICU | 1 (2%) | |
| Overall discharge rate | 22 (43%) | |
| Mortality rate | 29 (57%) | |
| Vital signs at admission | ||
| Systolic BP (mmHg) | 89 (±24.9) | 82 (40–160) |
| Diastolic BP (mmHg) | 55 (±17.6) | 50 (20–111) |
| Heart rate (beats/min) | 96 (±27.1) | 99 (32–153) |
| Body temperature (°C) | 37 (±4.5) | 36 (33.4–39) |
| O2 saturation (%) | 93 (±3.7) | 94 (85–99) |
| Mean arterial pressure (MAP, mmHg) | 64 (±18.1) | 61 (26–123) |
| Laboratory results | ||
| WBC (×10³ /mL) | 12,400 | 9500 (500–36100) |
| Lactate (mmol/L) | 3.Nis | 2.02 (0.4–20) |
| Ultrasound measurements | ||
| Carotid artery doppler flow velocity (CADFV, cm/s) | 43 (±16.7) | 48 (12–66) |
| Corrected carotid flow time (ccFT, ms) | 382 (±102.2) | 390 (134–651) |
| Inferior vena cava diameter (IVC, cm) | 1.8 (±0.39) | 1.08 (1.2–1.7 |
| IVC collapsibility index (IVCCI, %) | 59 (±13.6) | 60 (12–85) |
BP: blood pressure, MAP: mean arterial pressure, WBC: white blood cell count, CADFV: carotid doppler flow velocity, ccFT: corrected carotid flow time, IVC: inferior vena cava, IVCCI: inferior vena cava collapsibility index.
No statistically significant associations were found between CADFV and IVCCI values across the clinical parameters (p > 0.05). The mean CADFV was 50 cm/s in the intubated patients and 48 cm/s in the non-intubated patients, with no significant difference (p = 1.000). The IVCCI values were also similar, with 61% in intubated patients and 60% in non-intubated patients (p = 0.477). Patients receiving vasopressors had a mean CADFV of 48 cm/s compared with 28 cm/s in those without vasopressors (p = 0.259). The IVCCI was 61% in vasopressor-supported patients and 57.5% in those not receiving vasopressors (p = 0.739). CADFV was 33 cm/s in patients with a stroke history and 43 cm/s in those without (p = 0.127), 48 cm/s in hypertensive patients compared to 34 cm/s in non-hypertensive patients (p = 0.245), 50 cm/s in diabetic patients versus 48 cm/s in non-diabetic patients (p = 0.568), 40 cm/s in patients with malignancy, 44 cm/s in those without (p = 0.489), and 56 cm/s in CKD patients compared to 42 cm/s in patients without CKD (p = 0.146). Patients with CAD had a CADFV of 55 cm/s compared with 39 cm/s in those without CAD (p = 0.109). Table 2 presents the CADFV and IVCCI variations with respect to intubation, vasopressor use, and presence of comorbidities.
Table 2.
Association of carotid Doppler flow velocity and inferior vena cava collapse index with clinical parameters.
| Yes | No | p * | Yes | No | p * | |
|---|---|---|---|---|---|---|
|
Measurements
|
Intubation
|
Vasopressor
|
||||
| CADFV (cm/s) | 50 | 48 | 1.000 | 48 | 28 | 0.259 |
| IVCCI (%) |
61 |
60 |
0.477 |
61 |
57.5 |
0.739 |
|
Measurement
|
Stroke
|
Hypertension
|
||||
| CADFV (cm/s) | 33 | 43 | 0.127 | 48 | 34 | 0.245 |
|
DM
|
CAD
|
|||||
| 50 | 48 | 0.568 | 55 | 39 | 0.109 | |
|
Malignancy
|
CKD
|
|||||
| 40 | 44 | 0.489 | 56 | 42 | 0.146 | |
Mann‒Whitney U test.
CADFV: carotid artery Doppler flow velocity (cm/s), IVCCI: inferior vena cava collapse index (%), DM: diabetes mellitus, CAD: coronary artery disease, CKD: chronic kidney disease.
CADFV was significantly lower in deceased patients, with a mean of 37.55 cm/s compared to 49.14 cm/s in discharged patients (p = 0.026). The IVCCI was also significantly higher in deceased patients, with an average of 63%, as opposed to 55% in those discharged (p = 0.012). CVP values were lower in deceased patients, with a mean of 1.62 mmH₂O compared to 3.45 mmH₂O in discharged patients (p = 0.008). Table 3 presents a comparison of ultrasound measurements based on patient outcomes.
Table 3.
Comparison of ultrasound measurements based on patient outcomes.
| Ultrasound measurements | Outcome | Mean (SD) | Median | IQR | p* |
|---|---|---|---|---|---|
| CADFV (cm/s) | Discharged | 49.14 (±14.23) | 55 | 20 | 0.026 |
| Deceased | 37.55 (±16.98) | 32 | 28 | ||
| ccFT (ms) | Discharged | 399 (±89) | 413 | 86 | 0.159 |
| Deceased | 369 (±110) | 371 | 128 | ||
| VCI diameter (cm) | Discharged | 1.91 (±0.4) | 1.97 | 0.6 | 0.064 |
| Deceased | 1.71 (±0.38) | 1.07 | 0.5 | ||
| IVCCI (%) | Discharged | 55 (±13.12) | 54.5 | 16 | 0.012 |
| Deceased | 63 (±13.28) | 63 | 15 | ||
| CVP (mmH2O) | Discharged | 3.45 (±2.72) | 3 | 3 | 0.008 |
| Deceased | 1.62 (±0.37) | 1 | 2 |
Mann-Whitney U test.
CADFV: carotid artery Doppler flow velocity (cm/s), ccFT: corrected carotid flow time (ms), VCI diameter: Inferior vena cava diameter (cm), IVCCI: inferior vena cava collapse index (%), CVP: central venous pressure (mmH₂O).
The assessment correlation analyzes showed a moderate positive correlation between CVP and CADFV (k = 0.49, p = 0.00) and between VKI diameter and CADFV (k = 0.54, p = 0.00). A moderate negative correlation was found between CVP and IVCCI (k = −0.64, p = 0.00), suggesting that as IVCCI increases, CVP tends to decrease, which could indicate a reduced central venous return in patients with septic shock. These correlations emphasize that the CADFV, IVCCI, and CVP provide complementary insights into the hemodynamic status of patients with septic shock. Table 4 presents the Spearman correlation analysis between the hemodynamic and ultrasound parameters.
Table 4.
Correlation matrix of hemodynamic and Doppler measurements.
| Measurements | CVP (mmH₂O) | VKI diameter (cm) | IVCCI (%) | CADFV (cm/s) | ccFT (ms) | MAP (mmHg) |
|---|---|---|---|---|---|---|
| CVP (mmH₂O) | — | k = 0.30* | k = −0.64** | k = 0.49** | k = 0.07 | — |
| p = 0.03 | p = 0.00 | p = 0.00 | p = 0.64 | |||
| VCI diameter (cm) | k = 0.30* | — | k = −0.46** | k = 0.54** | k = 0.16 | — |
| p = 0.03 | p = 0.00 | p = 0.00 | p = 0.27 | |||
| IVCCI (%) | k = −0.64** | k = −0.46** | — | k = −0.58** | k = −0.06 | — |
| p = 0.00 | p = 0.00 | p = 0.00 | p = 0.66 | |||
| CADFV (cm/s) | k = 0.49** | k = 0.54*** | k = −0.58** | — | k = −0.06 | k = 0.30* |
| p = 0.00 | p = 0.00 | p = 0.00 | p = 0.70 | p = 0.03 | ||
| ccFT (ms) | k = 0.07 | k = 0.16 | k = −0.06 | k = −0.06 | — | k = 0.21 |
| p = 0.64 | p = 0.27 | p = 0.66 | p = 0.70 | p = 0.13 |
Spearman's correlation, Weak correlation (*): 0.10 < |k| < 0.30, Moderate correlation (**): 0.30 ≤ |k| < 0.60, High correlation (***): |k| ≥ 0.60.
CVP: central venous pressure (mmH₂O), VCI Diameter: inferior vena cava diameter (cm), IVCCI: inferior vena cava collapse index (%), CADFV: carotid artery Doppler flow velocity (cm/s), ccFT: corrected carotid flow time (ms), MAP: mean arterial pressure (mmHg).
Receiver operating characteristic (ROC) analysis was performed to investigate the predictive performance of CADFV, IVCCI, and CVP for mortality. The CADFV-Mortality ROC Curve showed an AUC of 0.68, indicating moderate discrimination capability, with a sensitivity of 72% and specificity of 68% at a cutoff value of 50 cm/s. The IVCCI mortality ROC curve showed a higher AUC of 0.71, with a sensitivity of 93% and specificity of 85%, which was achieved at a cutoff of 54.5%. IVCCI demonstrates strong predictive performance with high sensitivity for detecting mortality risk. The CVP-mortality ROC curve showed an AUC of 0.72, underscoring CVP's predictive capability with 61% sensitivity and 71% specificity at a 1.5 mmH₂O cutoff. Figure 2 presents the ROC curves for the three key parameters, CADFV, IVCCI, and CVP, in assessing their predictive performance for mortality.
Figure 2.
Predictive ROC curves for mortality based on hemodynamic and Doppler measurements.
5. Discussion
Early detection and intervention in patients with septic shock, especially before irreversible stages, are crucial in reducing mortality. Rapid volume assessment remains essential in the management of septic shock, particularly because the initial phase of resuscitation often involves fluid therapy. This study used noninvasive bedside ultrasound to assess volume status and predict mortality in septic shock patients by measuring CADFV, IVCCI, CVP, and IVC diameter, providing an accessible and efficient approach for emergency clinicians. Our study results show us that CADFV can be a useful predictor of mortality in patients with septic shock. In addition, the IVCCI and CVP also demonstrated predictive value for mortality. Significant correlations were observed between CADFV, IVCCI, and CVP. This indicates that these parameters can provide complementary insights for assessing volume status and guiding treatment in patients with septic shock.
The cohort, with a mean age of 67 years, was comparable to the literature, which reported a mean age of 60–70, indicating that advanced age is prevalent among critically ill patients presenting with septic shock [13]. The observed 57% mortality rate was aligned with global reports on septic shock, which remains one of the most lethal conditions in emergency and ICU settings [14]. The high prevalence of septic shock (88% in this study) corroborates with other studies that emphasized the high mortality associated with septic shock [15]. Malignancy was present in 45% of the patients, a significantly higher proportion than the 5% reported by Blehar et al. [16]. This discrepancy may be attributed to the patient population at our center, which includes a large number of oncology cases. Similarly, hypertension was observed in 43% of our cohort, which is consistent with the findings of Hossein-Nejad et al., who reported a high prevalence of hypertension among patients with septic shock [17]. These variations in comorbidities underscore the necessity to consider patient demographics and underlying health conditions when interpreting the study results, as these factors can influence mortality and treatment response in septic shock.
With the increasing utilization of ultrasound, noninvasive parameters such as IVC diameter and IVCCI are frequently employed in septic shock assessment, potentially superseding invasive methods such as CVP measurement. The present study observed an average IVC diameter of 1.8 cm in patients with volume deficits, which is consistent with the 1.8 cm threshold reported by Salahuddin et al. [18]. Furthermore, the mean IVCCI value of 59% in this investigation was congruent with that reported by Nagi et al., who noted that an IVCCI > 50% correlates with hypovolemia [19]. The use of IVCCI as a surrogate for invasive measurements is substantiated by these findings and aligns with those of Soliman et al., who demonstrated that IVCCI accurately reflects the fluid status in critically ill patients [20].
Regarding mortality prediction, ROC analysis revealed that CADFV, IVCCI, and CVP provided significant predictive insights. The CADFV-Mortality ROC Curve exhibited an area under the curve (AUC) of 0.68, indicating moderate predictive ability with 72% sensitivity and 68% specificity at a cutoff of 50 cm/s. These findings are consistent with those of Ma et al., who demonstrated that CADFV correlates with cardiac output and can predict outcomes in patients with septic shock [21]. The IVCCI-Mortality ROC Curve demonstrated superior predictive power with an AUC of 0.71, 93% sensitivity, and 85% specificity at a cutoff of 54.5%. Our findings are consistent with those of Airapetian et al., who reported an AUC of 0.78 IVCCI, further validating its role as a robust predictor of mortality [22]. The CVP-Mortality ROC curve, with an AUC of 0.72, underscores CVP's utility of CVP in mortality prediction, although previous studies such as reviews and meta-analyzes reported slightly lower AUC values, highlighting the variability in CVP effectiveness based on patient characteristics and septic shock type [23–25].
The correlation analysis in this study revealed a moderate positive association between CVP and CADFV (k = 0.49) and between VKI diameter and CADFV (k = 0.54), indicating that these parameters are interrelated and may collectively reflect central venous pressure status. Furthermore, a moderate negative correlation between CVP and IVCCI (k = −0.64) was observed, suggesting an inverse relationship wherein IVCCI increases as CVP decreases, a pattern characteristic of hypovolemic states. This finding aligns with the work of Zhang et al., who identified a relationship between CVP and IVC diameter, further supporting the notion that non-invasive ultrasound parameters can provide a comprehensive assessment of volume status without necessitating invasive measurements [26].
As a conclusion using carotid artery Doppler flow velocity for patient follow-up may navigate fluid resuscitation and may lower mortality.
5.1. Limitations and future directions
Although this study provides valuable insights into the utility of CADFV, IVCCI, and CVP for volume assessment and mortality prediction, it is limited by its sample size and single-center design. Future studies should focus on larger multicenter cohorts to validate these findings, and further research is warranted to establish standardized cut-off values and explore the integration of these ultrasound parameters with other hemodynamic markers.
Based on current literature, it is known that invasive measurements are the gold standard for determining fluid status. However, these invasive measurements have now been replaced by noninvasive alternatives. Due to this difference in practice, it is known that the use of invasive methods, even for research purposes, negatively impacts patient comfort and increases the risk of complications. Therefore, for the reasons mentioned above, ethics committees do not prefer the use of methods considered gold standards according to the literature. The fact that the comparisons made within the study did not include the true gold standard, invasive measurements, is considered a potential error in the evaluation, although it is unlikely.
6. Conclusion
Bedside ultrasound with CADFV, IVCCI, and CVP provides an effective, noninvasive assessment of volume status in patients with septic shock. Lower CADFV (<50 cm/s) and CVP (<1.5 mmH₂O), along with higher IVCCI (>54.5%), were linked to increased mortality. These parameters offer strong sensitivity and specificity, supporting their use for mortality prediction. Ultrasound-based volume assessment should be considered a viable alternative to invasive methods in emergency settings. Further research with larger cohorts is essential to confirm these findings and refine the cut-off values.
7. The main outcomes of the study
Predictive Value of carotid artery Doppler flow velocity (CADFV): This study found that the CADFV can be a useful predictor of mortality in patients with septic shock. A cut-off value of 50 cm/s for the CADFV was identified, with 72% sensitivity and 68% specificity for predicting mortality.
Role of the inferior vena cava collapsibility index (IVCCI): The IVCCI also demonstrated a predictive value for mortality, with a cut-off of 54.5%, providing 93% sensitivity and 85% specificity.
Central venous pressure (CVP) is a Mortality Predictor: The study established that CVP measurements can aid in mortality prediction, with a cutoff value of 1.5 mmH2O was determined, yielding 61% sensitivity and 71% specificity.
Correlation between CADFV, IVCCI, and CVP: Significant correlations were observed between CADFV, IVCCI, and CVP. These, indicating that these parameters can provide complementary insights for assessing volume status and guiding treatment in patients with septic shock.
Demographic Insights and Outcomes: The study included 51 septic shock patients with a mean age of 67 years. A mortality rate of 57% was observed in the present study. Septic shock was the most common diagnosis, found in 88% of the cases, highlighting the critical condition of the patient cohort.
These findings suggest that non-invasive ultrasound measures, such as CADFV and IVCCI, alongside CVP may be valuable in assessing volume status and predicting mortality in emergency department settings for patients experiencing septic shock.
Author contributions
None.
Disclosure statement
No potential conflict of interest was reported by the author(s).
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