Inferior Vena Cava Diameter is an Early Marker of Central Hypovolemia during Simulated Blood Loss

Comparison of tricuspid and mitral annular plane systolic excursion in determination of acute blood loss in healthy volunteers

Ultrasound is used more and more in determining acute blood loss. This study is to compare tricuspid annular plane systolic excursion (TAPSE) and mitral annular plane systolic excursion (MAPSE) measurement to determine volume loss pre and post blood donation in healthy volunteers. The systolic, diastolic and mean arterial blood pressures and pulses of the donors were measured in the standing and supine position by the attending physician, then, inferior vena cava (IVC), TAPSE and MAPSE measurements were made pre and post blood donation. Statistically significant differences were found in systolic blood pressure and pulse rate values that obtained in the standing position, and in the systolic blood pressure, diastolic blood pressure, mean arterial pressure and pulse values that obtained in the supine position (p < 0.05). The difference between IVC expiration (IVCexp) pre and post blood donation was 4.76 ± 2.94 mm, and the difference in IVC inspiration (IVCins) was 2.73 ± 2.91 mm. In addition, the MAPSE and TAPSE differences were 2.16 ± 1.4 mm and 2.98 ± 2.13 mm, respectively. Statistically significant differences were found between IVCins-exp, TAPSE and MAPSE values. TAPSE and MAPSE can be helpful in the early diagnosis of acute blood loss.

Inferior vena cava diameter on CT angiography predicts mesenteric angiography positive for extravasation in colonic diverticular bleeding

PURPOSE

Transcatheter arterial embolization (TAE) for colonic diverticular bleeding (CDB), an established procedure for hemostasis, is sometimes complicated by spontaneous hemostasis and unclear bleeding site on angiography despite active arterial bleeding on preoperative computed tomography angiography (CTA). Therefore, to investigate and increase the feasibility of TAE, this retrospective study evaluates the clinical and radiological features related to positive extravasation on angiography.

MATERIAL AND METHODS

Sixty CDB patients with extravasation on CTA underwent TAE between January 2011 and February 2021 and were divided into extravasation-positive (P-group; n = 25) and -negative groups (N-group; n = 35) based on the superior or inferior mesenteric angiography. Patient characteristics, laboratory findings, the diameter of the inferior vena cava (IVCD), the diameter of superior and inferior mesenteric veins, and technical outcomes were evaluated.

RESULTS

TAE was successful in 24 patients in the P-group (96%) and 14 in the N-group (40%) (p < 0.001). Univariate analysis revealed "usage of anticoagulant" (p < 0.05) and "larger IVCD (p < 0.05) on preoperative CTA" to be significant predictors of positive extravasation. In the multivariate analysis, IVCD remained significant with an adjusted odds ratio of 1.17. The IVCD cutoff value was 13.6 mm (area under the curve = 0.72, sensitivity = 84.0%, specificity = 54.3%). There were no significant differences in other parameters.

CONCLUSION

Measurement of IVCD in CDB with the cutoff value of 13.6 mm can be a simple and useful indicator to predict the detectability of extravasation following TAE procedures.

Ultrasonographical Assessment of Caudal Vena Cava Size through Different Views in Healthy Calves: A Pilot Study

Ultrasonographic measurements of the caudal vena cava (CVC) and aorta (Ao) are known as reliable tools to assess intravascular volume status in humans. The aim of this study was to evaluate the feasibility of obtaining ultrasonographical measurements of CVC and Ao in two different views, assess intra- and interobserver variability, and study the effect of sex, age, body weight, and breed on measurements in healthy calves. The diameter and area of CVC and Ao were measured by a single investigator in two anatomic sites (subxiphoid and paralumbar window) in 48 calves aged less than 60 days and then repeated 2.5 months after the first assessment. For intra- and interobserver variability assessment, CVC and Ao measurements were repeated by three observers on five randomly selected calves. CVC and Ao measurements were easily obtained in PV and more difficult to obtain in SV. CVC and Ao area in PV showed high repeatability and reproducibility. A positive correlation was highlighted between age and CVC and Ao measurements in both sites. In conclusion, CVC size assessment by point of care ultrasound can be easily performed at a paralumbar site in calves under 4 months of age and could be used to assess intravascular volume status.

The role of mitral annular plane systolic excursion in prediction of acute blood loss in healthy voluntary blood donors

Aim

The aim of this study is to compare the diameter of the inferior vena cava with mitral annular plane systolic excursion measurement in order to determine the volume loss before and after blood donation in healthy volunteers.

Material and methods

The study was a single-center, prospective, cross-sectional study which included 46 healthy blood donors donating in a tertiary care hospital's blood bank. The inclusion criteria for the study were: volunteers aged 18-65 years, over 50 kg in weight, who met blood donation criteria, with hemoglobin values of >13.5 g/dL for males and >12.5 g/dL for females. After obtaining written consent, the systolic, diastolic, and mean arterial blood pressure along with the pulse rate of the donors were measured in standing and lying positions by the attending physician. Next, inferior vena cava and mitral annular plane systolic excursion measurements were made both pre and post blood donation.

Results

The decrease in both inferior vena cava diameter and mitral annular plane systolic excursion values measured pre and post blood donation was found to be statistically significant (p <0.05). There was no difference between the other variables pre and post blood donation.

Conclusions

Our study revealed that decreased inferior vena cava and mitral annular plane systolic excursion values correlated in determining blood loss post blood donation. Mitral annular plane systolic excursion may be useful to predict blood loss in the early stages of hemorrhagic shock.

Point-of-Care Ultrasound for the Trauma Anesthesiologist

Purpose of Review

With advances in technology and availability of handheld ultrasound probes, studies are focusing on the perioperative care of patients, but a limited number specifically on trauma patients. This review highlights recent findings from studies using point of care ultrasound (POCUS) to improve the care of trauma patients.

Recent Findings

Major findings include the use of POCUS to assess volume status of trauma patients upon arrival to measure the major vasculature. Additionally, several studies have advanced the use of POCUS to identify pneumothorax in trauma patients. Finally, the ASA POCUS certification and ASRA expert guidelines are examples of international organizations establishing guidelines for utilization and training of anesthesiologists in the field of POCUS, which will be discussed.

Summary

Despite the COVID-19 pandemic, and considerable resources being diverted to fight this global healthcare crisis, advances are being made in utilization of POCUS to aid the care of trauma patients.

The role of tricuspite annular plane systolic excursion as a marker of hypovolemia in healthy blood donor volunteers

AIM

The aim of this study is to compare the diameter of the inferior vena cava with tricuspid annular plane systolic excursion (TAPSE) measurement in order to determine the volume loss before and after blood donation in healthy volunteers.

METHODS

This Institutional Review Board-approved single center, prospective, cross-sectional study included 60 healthy blood donors donating in a tertiary care hospital's blood bank. After obtaining written consent, systolic, diastolic, and mean arterial blood pressures along with pulse rate of the donors were measured in sitting and supine positions by the attending physician, then, inferior vena cava (IVC) and TAPSE measurements were made before and after blood donation.

RESULTS

Statistically significant differences was found between standing systolic blood pressure and pulse rate, lying systolic blood pressure and pulse rate, IVC and TAPSE values before and after blood donation (p < 0.05). There was no difference between the other variables before and after blood donation.

CONCLUSION

Our study revealed that, low IVC and TAPSE values correlated in determining blood loss after blood donation. TAPSE may be useful to predict blood loss in early stages of hypovolemic shock.

Ultrasonographic Inferior Vena Cava Measurement is More Sensitive Than Vital Sign Abnormalities for Identifying Moderate and Severe Hemorrhage

BACKGROUND

Ultrasound inferior vena cava (IVC) diameter has been shown to decrease in response to hemorrhage. IVC diameter cut points to identify moderate and severe blood loss have not been established.

OBJECTIVES

This study sought to find ultrasound IVC diameter cut points to identify moderate and severe hemorrhage and assess the performance of these cut points vs. vital sign abnormalities.

METHODS

This is a secondary analysis of data from a study that described changes in vital signs and sonographic measurements of the IVC during a lower body negative pressure model of hemorrhage. Using receiver operator curve analyses, optimal cut points for identifying moderate and severe hemorrhage were identified. The ability of these cut points to identify hemorrhage in patients with no vital sign abnormalities was then assessed.

RESULTS

In both long- and short-axis views, maximum and minimum IVC diameters (IVC_max and IVC_min) were significantly lower than baseline in severe blood loss. The optimal cut point for IVC_max in both axes was found to be ≤ 0.8 cm. This cut point is able to distinguish between no blood loss vs. moderate blood loss, and no blood loss vs. severe blood loss. The optimal cut point for IVC_min was variable between axes and blood loss severity. IVC diameter cut points obtained were able to identify hemorrhage in patients with no vital sign abnormalities.

CONCLUSION

An ultrasound IVC_max of ≤ 0.8 cm may be useful in identifying moderate and severe hemorrhage before vital sign abnormalities are evident.