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Background: The likelihood of a patient being preload responsive—a state where the cardiac output or stroke volume (SV) increases significantly in response to preload—depends on both cardiac filling and function. This relationship is described by the canonical Frank-Starling curve. Research Question : We hypothesize that a novel method for phenotyping hypoperfused patients (ie, the "Doppler Starling curve") using synchronously measured jugular venous Doppler as a marker of central venous pressure (CVP) and corrected flow time of the carotid artery (ccFT) as a surrogate for SV will refine the pretest probability of preload responsiveness/unresponsiveness. Study Design and Methods: We retrospectively analyzed a prospectively collected convenience sample of hypoperfused adult emergency department (ED) patients. Doppler measurements were obtained before and during a preload challenge using a wireless, wearable Doppler ultrasound system. Based on internal jugular and carotid artery Doppler surrogates of CVP and SV, respectively, we placed hemodynamic assessments into quadrants (Qx) prior to preload augmentation: low CVP with normal SV (Q1), high CVP and normal SV (Q2), low CVP and low SV (Q3) and high CVP and low SV (Q4). The proportion of preload responsive and unresponsive assessments in each quadrant was calculated based on the maximal change in ccFT (ccFTΔ) during either a passive leg raise or rapid fluid challenge. Results: We analyzed 41 patients (68 hemodynamic assessments) between February and April 2021. The prevalence of each phenotype was: 15 (22%) in Q1, 8 (12%) in Q2, 39 (57%) in Q3, and 6 (9%) in Q4. Preload unresponsiveness rates were: Q1, 20%; Q2, 50%; Q3, 33%, and Q4, 67%. Interpretation: Even fluid naïve ED patients with sonographic estimates of low CVP have high rates of fluid unresponsiveness, making dynamic testing valuable to prevent ineffective IVF administration. [ABSTRACT FROM AUTHOR]

The accurate identification of perforator veins (PV) in asymptomatic veins that do not meet the criteria established by venous Doppler (VD) is a complex challenge, considered the gold standard in diagnosis, and is operator-dependent. This study explored the potential of dual infrared–visual thermography (IRVT) to identify PV in 99 patients aged 29 to 80 years. IRVT was conducted using a high-definition hyperspectral visual–infrared sensor. The temperature difference (ΔT) between maximum temperature (Tmax) and minimum temperature (Tmin) within the region of interest (ROI) served as an indicator for assessing vascular dysfunction severity. Comparative analysis was performed with VD results obtained using a Doppler ultrasound unit equipped with a 7.5 MHz linear transducer. Significant statistical differences (p < 0.05) in ΔT (Tmax−Tmin) were observed among PV sites categorized by reflux severity: no reflux (ΔT = 1.2 °C), mild reflux (ΔT = 1.8 °C), moderate reflux (ΔT = 2.9 °C), and severe reflux (ΔT = 3.6 °C). This study concludes that IRVT effectively distinguishes varying degrees of vascular reflux severity. IRVT shows promise as a non-invasive, radiation-free tool to enhance PV identification, especially in challenging cases, potentially improving patient outcomes and healthcare management. Further research is required to validate and refine its diagnostic utility. [ABSTRACT FROM AUTHOR]

Providing intravenous (IV) fluids to a patient with signs or symptoms of hypoperfusion is common. However, evaluating the IV fluid 'dose–response' curve of the heart is elusive. Two patients were studied in the emergency department with a wireless, wearable Doppler ultrasound system. Change in the common carotid arterial and internal jugular Doppler spectrograms were simultaneously obtained as surrogates of left ventricular stroke volume (SV) and central venous pressure (CVP), respectively. Both patients initially had low CVP jugular venous Doppler spectrograms. With preload augmentation, only one patient had arterial Doppler measures indicative of significant SV augmentation (i.e., 'fluid responsive'). The other patient manifested diminishing arterial response, suggesting depressed SV (i.e., 'fluid unresponsive') with evidence of ventricular asynchrony. In this short communication, we describe how a wireless, wearable Doppler ultrasound simultaneously tracks surrogates of cardiac preload and output within a 'Doppler Starling curve' framework; implications for IV fluid dosing are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives To investigate fetal venous Doppler measurements in monochorionic twin pregnancies complicated by placental insufficiency and the relationship between fetal venous flow and acidemia at birth or intrauterine fetal death. Methods This was a prospective study of 18 monochorionic twin pregnancies with placental insufficiency. Inclusion criteria were monochorionic-diamniotic twin pregnancy, abnormal umbilical artery ( UA) Doppler indices, intact membranes and absence of fetal congenital abnormalities. Cases of twin-to-twin transfusion syndrome were excluded. The following Doppler measurements were studied: UA pulsatility index ( PI), ductus venosus PI, middle cerebral artery PI and peak systolic velocity, intra-abdominal umbilical vein ( UV) time-averaged maximum velocity ( TAMXV) and left portal vein ( LPV) TAMXV. Doppler parameters were transformed into Z- scores ( SD values from the mean) or multiples of the median according to normative references. Results UA pH < 7.20 occurred in nine (25.0%) neonates, pH < 7.15 in four (11.1%) and intrauterine death in four (11.1%) fetuses. The UV-TAMXV and LPV-TAMXV Z- scores were significantly lower in the group with pH < 7.20 or intrauterine fetal death (-1.79 vs - 1.22, P = 0.006 and -2.26 vs - 1.13, P = 0.04, respectively). In cases with pH < 7.15 or intrauterine fetal death, UV pulsations were more frequent (50.0% vs 10.7%, P = 0.03) and UV-TAMXV Z- score was significantly lower (-1.89 vs - 1.26, P = 0.003). Mixed effects logistic regression analysis, accounting for the paired nature of the outcomes for the two twins in each pregnancy, demonstrated that the UV-TAMXV Z- score significantly predicted UA pH at birth < 7.20 or intrauterine fetal death. The Doppler parameter that independently predicted pH < 7.15 or intrauterine fetal death was presence of pulsation in the UV. Conclusion UV Doppler parameters may predict acidemia at birth or intrauterine fetal death in monochorionic twins complicated by placental insufficiency. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objective: This study was undertaken to test which venous Doppler parameter offers the best prediction of acid-base status at birth in pregnancies complicated by intrauterine growth restriction (IUGR) caused by placental dysfunction. Study Design: A prospective cross-sectional Doppler study of IUGR fetuses with abnormal umbilical artery Doppler and birth weight less than the 10th percentile. Absence of atrial systolic forward velocities in the ductus venosus (DV) (DV-RAV) and umbilical vein (UV) pulsations were noted and multiple venous indices were calculated for the inferior vena cava (IVC) and DV (IVC and DV preload index, peak velocity index [PVIV] and pulsatility index [PIV] and the DV S/a ratio). Doppler indices, UV pulsations, and DV- RAV were related to an umbilical artery cord pH <7.20, and a pH <7.00 and/or base deficit greater than -13 (severe metabolic compromise) in neonates delivered by cesarean section without labor. Results: In 122 fetuses all venous Doppler indices were equally predictive of a pH <7.20, with the exception of the IVC PVIV. No Doppler index predicted severe metabolic compromise. Bayesian analysis of individual Doppler parameters showed comparable outcome prediction with the highest sensitivity for the IVC PIV (76%) and the highest specificity for DV-RAV (96%). Combined assessment of the IVC, DV, and UV provided the most accurate outcome prediction. Doppler abnormality in either vessel identified 89% of neonates with pH <7.20 (negative predictive value 92%) and 10 of 11 neonates with severe metabolic compromise. Prediction was most specific (84%) when Doppler parameters were abnormal in all 3 vessels. Conclusion: IVC, DV, and UV Doppler parameters correctly predict acid-base status in a significant proportion of IUGR neonates. Combination, rather than single vessel assessment provides the best predictive accuracy. While the choice of Doppler index can be guided by operator preference, familiarity with the examination technique of all 3 vessels is encouraged to offer the highest flexibility in clinical practice. [ABSTRACT FROM AUTHOR]

Objective The objective of the current study was to evaluate fetal arterial and venous Doppler parameters in postterm pregnancies with oligohydramnios and those with normal amniotic fluid. Study Design A cross-sectional study was performed in 38 pregnancies beyond 41 weeks' gestation. Pulsed Doppler imaging was used to determine the pulsatility index (PI) for the fetal middle cerebral artery (MCA), renal artery, umbilical artery, inferior vena cava (IVC) and ductus venosus. The amniotic fluid index (AFI) was used for semiquantitive assessment of amniotic fluid volume. Oligohydramnios was defined as an AFI < 5 cm. Results Oligohydramnios was detected in 10 cases, and a normal AFI was present in 28 cases. In the presence of oligohydramnios the PI of the MCA was decreased, while the renal artery PI and the MCA PI/UA PI ratio were found to be elevated. In cases of oligohydramnios the PI in the IVC was increased but was unchanged in the ductus venosus. Conclusion Oligohydramnios in post-term pregnancies is associated with arterial redistribution of fetal blood flow typifying the brain sparing effect and with decreased resistance in the MCA and increased resistance in the fetal IVC. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the role of the venous system in cyclical mastalgia. Materials and methods: 25 healthy women and 39 women with cyclic mastalgia underwent venous Doppler examination in both pre- and postmenstrual period. Upper-outer quadrant veins of breast were evaluated. The impedance indices of both groups were compared in both the premenstrual and postmenstrual period. Results: During the premenstrual period, venous impedance indices were significantly higher in the patients with cyclic mastalgia (p =0.004) than in the control group. After the menstrual period, there was no difference in venous impedance indices between the groups. Conclusion: Excessive tissue oedema might be responsible for both a tension-mediated pain and a compression of the venous system thereby showing higher impedance than that in control group. [Copyright &y& Elsevier]