Venous Velocity Research Articles

Effects of nonselective internal iliac artery angioembolization on pelvic venous flow in the swine model.

Pelvic angioembolization (AE) is a mainstay in the treatment algorithm for pelvic hemorrhage from pelvic fractures. Nonselective AE refers to embolization of the bilateral internal iliac arteries (IIAs) proximally rather than embolization of their tributaries distally. The aim of this study was to quantify the effect of nonselective pelvic AE on pelvic venous flow in a swine model. We hypothesized that internal iliac vein (IIV) flow following IIA AE is reduced by half. Nine Yorkshire swine underwent nonselective right IIA gelfoam AE, followed by left. Pelvic arterial and venous diameter, velocity, and flow were recorded at baseline, after right IIA AE and after left IIA AE. Linear mixed-effect model and signed rank test were used to evaluate significant changes between the three time points. Eight swine (77.8 ± 7.1 kg) underwent successful nonselective IIA AE based on achieving arterial resistive index of 1.0. One case was aborted because of technical difficulties. Compared with baseline, right IIV flow rate dropped by 36% ± 29% (p < 0.05) and 54% ± 29% (p < 0.01) following right and left IIA AE, respectively. Right IIA AE had no initial effect on left IIV flow (0.37% ± 99%, p = 0.95). However, after left IIA AE, left IIV flow reduced by 54% ± 27% (p < 0.01). Internal iliac artery AE had no effect on the external iliac arterial or venous flow rates and no effect on inferior vena cava flow rate. The effect of unilateral and bilateral IIA AE on IIV flow appears to be additive. Despite bilateral IIA AE, pelvic venous flow is diminished but not absent. There is abundant collateral circulation between the external and internal iliac vascular systems. Arterial embolization may reduce venous flow and improve on resuscitation efforts in those with unstable pelvic fractures. Prognostic, level IV.

Clinical and hemodynamic outcome of morbidly obese patients with severe chronic venous insufficiency with and without bariatric surgery

ObjectiveObesity is associated with several medical problems, including chronic venous insufficiency resistant to usual conservative measures. Venous intervention in patients with a body mass index (BMI) >30 kg/m2 is associated with a higher anesthetic risk and recurrence rate. The aim of the present study was to compare the severity of venous insufficiency in terms of the clinical findings and hemodynamics between morbidly obese patients who had and had not undergone bariatric surgery (BS). MethodsA total of 123 patients with morbid obesity and severe venous manifestations were included in the present study. The patients were divided into two groups. Group A included 72 patients who had undergone BS, and group B included 51 patients who had not undergone BS. Assessments were performed using both disease-specific and physician-generated tools and duplex ultrasonography. ResultsOf the 123 patients, 66% were men. The mean patient age was 44 ± 8.2 years. All the patients were followed up for 1 year. The mean BMI for group A had decreased from 50.1 ± 5.6 kg/m2 to 32.9 ± 4.2 kg/m2 (P = .0001). However, the mean BMI for group B had increased from 49.2 ± 6.1 kg/m2 to 50 ± 5.7 kg/m2 (P = .16). For the patients with a history of venous ulcer, the Charing Cross Venous Ulceration Questionnaire score for group A had decreased 77.5 to 36.8 (P = .0001) compared with a decrease in group B from 77.34 to 75.36 (P = .13). In group A, the median Venous Disability Score had improved from 2 to 0 and the median Venous Clinical Severity Score from 8.6 to 2.1 compared with nonsignificant changes in group B. The number of patients with venous claudication had decreased from 8 to 2 (P = .036) in group A compared with no changes in group B. For group A, the mean 36-item short-form heath survey score had increased from 48 ± 6.8 to 81 ± 4.4 (P = .001) compared with an increase from 52 ± 8.8 to 59 ± 1.2 (P = .52) in group B. The mean common femoral vein diameter had decreased significantly in group A (7.3 ± 1.3 mm) compared with that in group B (8.93 ± 1.08; P = .0001). The peak venous velocity showed higher values for the patients who had undergone BS (group A, 14.9 ± 2.5 cm/s; group B, 10.75 ± 2.05 cm/s; P = .0001). Higher mean velocities and a lower diameter resulted in a higher wall shear stress in group A compared with that in group B (2.2 ± 1.1 dyn/cm2 vs 1.16 ± 0.52 dyn/cm2; P = .0001). ConclusionsThe patients who had lost weight after BS experienced noticeable improvements in chronic venous insufficiency compared with the patients who had not lost weight, including an increased rate of ulcer healing, a decreased incidence of venous claudication, and improved quality of life.

Effects of intermittent pneumatic compression on femoral vein peak venous velocity during active ankle exercise.

The risk of developing deep vein thrombosis (DVT) is high even after the period of bed rest following major general surgery including total joint arthroplasty (TJA). Mobile intermittent pneumatic compression (IPC) devices allow the application of IPC during postoperative exercise. Although ambulation included ankle movement, no reports have been made regarding the effects of IPC during exercise, including active ankle exercise (AAE), on venous flow. This study was performed to examine whether using a mobile IPC device can effectively augment the AAE-induced increase in peak velocity (PV). PV was measured by Doppler ultrasonography in the superficial femoral vein at rest, during AAE alone, during IPC alone, and during AAE with IPC in 20 healthy subjects in the sitting position. PV in AAE with IPC was measured with a mobile IPC device during AAE in the strong compression phase. AAE was interrupted from the end of the strong compression phase to minimize lower limb fatigue. AAE with IPC (76.2 cm/s [95%CI, 69.0-83.4]) resulted in a significant increase in PV compared to either AAE or IPC alone (47.1 cm/s [95%CI, 38.7-55.6], p < 0.001 and 48.1 cm/s [95%CI, 43.7-52.4], p < 0.001, respectively). Reduced calf muscle pump activity due to the decline in ambulation ability reduced venous flow. Therefore, use of a mobile IPC device during postoperative rehabilitation in hospital and activity including self-training in an inpatient ward may promote venous flow compared to postoperative exercise without IPC. Use of a mobile IPC device significantly increased the PV during AAE, and simultaneous AAE with IPC could be useful evidence for the prevention of DVT in clinical settings, including after TJA.

Neuromuscular stimulation of the common peroneal nerve increases arterial and venous velocity in patients with venous leg ulcers.

Activation of the venous muscle pumps by neuromuscular stimulation of the common peroneal nerve has been previously shown to increase venous and arterial flow in the legs of healthy subjects. The aim of this study is to determine whether a similar effect is observed in patients with chronic venous leg ulcers. 1 Hz intermittent electrostimulation of the common peroneal nerve was applied to 14 patients with ulcers between 1 and 10 cm in diameter, eliciting a small, painless, regular, muscular twitch of the leg. Flow was measured using Duplex ultrasound in the popliteal vein and the popliteal artery. Peak arterial velocity increased from 57 to 78 cm/s (P = .001) in sitting position, and from 79 to 98 cm/s in recumbent position (P = .001). Peak venous velocity increased from 10 to 33 cm/s (P = .001) sitting, and from 14 to 47 cm/s (P = .001) recumbent. Significant increases were observed in both venous and arterial blood flow in the lower limb. This suggestsed that activation of the venous muscle pump and improvement of arterial flow assisted oxygen delivery at the wound site. Moreover this may be a worthwhile intervention to assist in the healing of venous leg ulcers, and may provide a mechanistic explanation for the increased healing rates previously reported with neuromuscular stimulation of the common peroneal nerve.

Clinical Application of High-frequency Ultrasound in Treatment of Infantile Hemangiomas.

To study the clinical application of high-frequency ultrasound in the treatment of infantile hemangiomas. Ultrasonographic data before and after treatment for 1 month, 3 months and 5 months were recorded from 80 patients with infantile hemangioma. The hemangioma was monitored dynamically with relevant indexes before and after treatment, and the treatment results were divided into 2 groups: the treatment-effective group of 70 cases and the treatment-ineffective group of 10 cases. The differences of tumor size, internal echo and hemodynamic parameters (peak arterial systolic flow velocity, resistance index and venous velocity) were compared before and after treatment, and reliable ultrasound observation indexes were summarized. After treatment, in the treatment-effective group, the thickness of tumor was reduced in all cases, the blood flow signals decreased in 55 cases, the peak systolic velocity decreased in 55 cases, resistance index increased in 55 cases, and venous flow velocity decreased in 53 cases; the differences were statistically significant compared with those before treatment (P < 0.05). The thickness of tumors was significantly decreased after 5 months of treatment compared with 1 month and 2 month treatment (P < 0.05). There was no significant difference in the longitudinal and transverse diameter of tumors after treatment (P > 0.05). In the treatment-ineffective group, there was no significant difference in the above indexes before and after treatment (P > 0.05). High-frequency ultrasound had primary application value in the treatment of infantile hemangiomas, where the change of tumor thickness provided the most important observational indicator.

Venous Pulse Wave Velocity variation in response to a simulated fluid challenge in healthy subjects

PurposeThe evaluation of a mini or simulated fluid challenge is still a complex and open issue in the clinical setting and it is of paramount significance for the fluid therapy optimization. We here investigated the capacity of a new hemodynamic parameter, the venous Pulse Wave Velocity (vPWV), to detect the effect of passive leg raising (PLR). Materials and methodsIn 15 healthy volunteers (7 M, 8 F, age 26 ± 3) venous pressure pulses were elicited by pneumatic compressions of the left hand and proximally detected by ultrasound for calculation of the vPWV. We also non-invasively measured the basilic vein (BV) cross-sectional perimeter, and peripheral venous pressure (PVP). The PLR manoeuvre was performed twice to evaluate reliability of the assessment. ResultsThe PLR had an overall statistically significant effect on the entire set of variables (MANOVA, p < 0.05): vPWV increased from 2.11 ± 0.46 to 2.30 ± 0.47 m/s (p = 0.01; average increase: 10%). This effect was transient and dropped below 5% after about 3 min. A significant increase was also exhibited by BV size and PVP. In consecutive measurements vPWV showed little intra-subject variability (CoV = 8%) and good reliability (ICC = 0.87). Finally, the vPWV responses to the two PLRs exhibited good agreement (paired T-test: p = 0.96), and moderate reliability (ICC = 0.57). ConclusionThese results demonstrated that vPWV can be non-invasively, objectively and reliably measured in healthy subjects and that it is adequate to detect small pressure/volume variations, as induced by PLR-from-supine. These characteristics make it suitable for clinical applications.

Venous pulse wave velocity

Central venous pressure and volume status are relevant parameters for the characterization of the patient's haemodynamic condition and for the management of fluid therapy however, their invasive assessment is affected by various risks and complications while non-invasive approaches provide only imprecise and subjective indications. Aim of the present study is to explore the possibility to assess changes in venous pressure from changes in the venous pulse wave velocity (vPWV). In 9 healthy subjects, pressure pulses were generated artificially in the veins by a PC-driven rapid inflation of a pneumatic cuff (300mmHg in

Cardiovascular magnetic resonance for the diagnosis and management of heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is characterized by an impaired ventricular filling resulting in the development of dyspnea and other HF symptoms. Even though echocardiography is the cornerstone to demonstrate structural and/or functional alterations of the heart as the underlying cause for the clinical presentation, cardiovascular magnetic resonance (CMR) represents the noninvasive gold standard to assess cardiac morphology, function, and tissue changes. Indeed, CMR allows quantification of biventricular volumes, mass, wall thickness, systolic function, and intra- and extracardiac flows; diastolic functional indices include transmitral and pulmonary venous velocities, left ventricular and left atrial filling velocities from volumetric changes, strain analysis from myocardial tagging, tissue phase contrast, and feature tracking. Moreover, CMR allows superior tissue characterization of the myocardium and the pericardium, which are crucial for a noninvasive etiological and histopathological assessment of HFpEF: conventional T1-weighted, T2-weighted, and post-contrast sequences are now complemented by quantitative mapping sequences, including T1 and T2 mapping as well as extracellular volume quantification. Further experimental sequences comprise diffusion tensor analysis, blood oxygenation-dependent sequences, hyperpolarized contrast agents, spectroscopy, and elastography. Finally, artificial intelligence is beginning to help clinicians deal with an increasing amount of information from CMR exams.

Markedly elevated hepatic arterial velocity-HAV greater than 200 cm/s-is not specific to hepatobiliary disease.

The aim of the study was to review the different etiologies and outcomes of patients with hepatic artery velocities greater than 200 cm/s. This retrospective study included 88 hospitalized patients in whom angle-corrected proper hepatic artery flow velocities greater than 200 cm/s were obtained during an abdominal ultrasonographic examination. Peak systolic hepatic artery flow velocities, hepatic artery resistance index, and portal vein flow velocities were evaluated. The patients were then allocated to one of four groups based on their primary underlying diagnosis: structural liver disease, nonstructural liver disease, generalized infection, or miscellaneous. The median hepatic artery velocity was similar for all groups, ranging from 226 to 238 cm/s. The maximum portal venous velocities were not significantly different between groups. No lab values were statistically different between the groups, except total bilirubin that was greater in the nonstructural liver disease group (8 mg/dL). Overall, 9/88 (10.2%) of patients with elevated hepatic artery velocity died within 30 days of their ultrasonographic examination. Elevated hepatic artery velocity greater than 200 cm/s in hospitalized patients is not specific to primary hepatobiliary disease but may indicate acute hepatic dysfunction from other causes such as infection or sepsis.

The use of intermittent pneumatic compression of the thigh to affect arterial and venous blood flow proximal to a chronic wound site.

Intermittent pneumatic compression of the lower limbs has been shown to have beneficial effects in patients with chronic ulceration. However, the intermittent compression cuff will normally be applied over the wound, which may produce discomfort or interfere with other treatments. Thigh‐only approaches to intermittent pneumatic compression could solve this problem. This study aimed to demonstrate if such a system would have positive effects on venous and arterial blood flow distal to the compression site, but proximal to wound sites. The distal venous and arterial effects of a prototype thigh‐only 3‐chamber sequential intermittent pneumatic compression system were tested in 20 healthy volunteers, and 13 patients with ulcers of various aetiologies using Doppler ultrasound. The system produced hyperaemic responses in the arterial flow of both test groups. The peak venous velocity on deflation of the first and second chambers of the cuff was also greater in the patients with ulceration than in the healthy volunteers (11.6 cm/s vs 8.3 cm/s, P = .1). This work demonstrates that compression of the thigh alone can produce positive haemodynamic effects in the calves of patients with chronic wounds, and that this approach should be investigated as a therapy to improve blood flow to wound sites.

Control of retinal blood flow levels by selected combinations of cervical arterial ligations in rat

The effect of various combinations of cervical arterial ligations (Combinations) on retinal blood flow (RBF) levels is not known in rats. We hypothesized: 1) No artery exists between the Circle of Willis and the eye, 2) Selective Combinations enable varying RBF levels between normal and zero, 3) In certain Combinations, the capillary bed of the head participates in supplying the eye. Twenty-six Combinations were studied in one eye of 20 Long-Evans rats under general anesthesia. RBF was quantitatively evaluated with our published imaging methods based on direct measurements of venous diameter and blood velocity from the displacement of fluorescent microspheres over time. For each Combination, one or more RBF values (runs) were measured. Data were obtained from 59 runs (2.9 ± 2.7 runs/rat). Levels of RBF ranged from normal to zero. An artery between the Circle of Willis and the eye was excluded. With some Combinations, flow traversed the capillary bed. Combinations were consolidated into five Groups based on the blood flow paths remaining after the ligations. A mixed linear model accounting for multiple measurements in the same eye demonstrated an effect of Group on RBF (P < 0.0005). By major source of ocular blood supply, the trend of RBF levels was: ipsilateral carotid artery > contralateral carotid artery > ipsilateral distal internal carotid artery retrograde from Circle of Willis. The findings advanced knowledge of the sources of blood supply to the rat eye and demonstrated a method of selective cervical arterial ligations for varying RBF levels with potential to impact future retinal ischemia research.

Comparison of the Hemodynamic Performance of Two Neuromuscular Electrical Stimulation Devices Applied to the Lower Limb.

Currently, 1% of the population of the Western world suffers from venous leg ulcers as a result of chronic venous insufficiency. Current treatment involves the use of moist wound healing, compression bandages, and intermittent pneumatic compression. Neuromuscular electrical stimulation is a novel potential new therapeutic method for the promotion of increased lower limb hemodynamics. The aim of this study was to measure the hemodynamic changes in the lower limb with the use of two neuromuscular electrical stimulation devices. Twelve healthy volunteers received two neuromuscular stimulation device interventions. The GekoTM and National University of Ireland (NUI) Galway neuromuscular electrical stimulation devices were randomized between dominant and non-dominant legs. Hemodynamic measurements of peak venous velocity (cm/s), the time average mean velocity (TAMEAN) (cm/s), and ejected volume (mL) of blood were recorded. Peak venous velocity was significantly increased by the GekoTM and the NUI Galway device compared to baseline blood flow (p < 0.0001), while only the voluntary contraction produced significant increases in TAMEAN and ejected volume (both p < 0.05). Neuromuscular muscular electrical stimulation can produce adequate increases in lower limb hemodynamics sufficient to prevent venous stasis. Greater use of neuromuscular stimulation devices could be considered in the treatment of conditions related to chronic venous insufficiency but requires further research.

Serum levels of bone sialoprotein correlate with portal pressure in patients with liver cirrhosis.

Liver cirrhosis represents the common end-stage of chronic liver diseases regardless of its etiology. Patients with compensated disease are mostly asymptomatic, however, progression to a decompensated disease stage is common. The available stratification strategies are often unsuitable to identify patients with a higher risk for disease progression and a limited prognosis. SIBLINGs, soluble glycophosphoproteins, are secreted into the blood by immune-cells. While osteopontin, the most prominent member of the SIBLINGs family, has been repeatedly associated with liver cirrhosis, data on the diagnostic and/or prognostic value of bone sialoprotein (BSP) are scarce and partly inconclusive. In this study, we analyzed the diagnostic and prognostic potential of circulating BSP in comparison to other standard laboratory markers in a large cohort of patients with liver cirrhosis receiving transjugular intrahepatic portosystemic shunt (TIPS). Serum levels of BSP were similar in patients with different disease stages and were not indicative for prognosis. Interestingly, BSP serum levels did correlate inversely with portal pressure, as well as its surrogates such as platelet count, the portal vein cross-sectional area and correlated positively with the portal venous velocity. In summary, our data highlight that BSP might represent a previously unrecognized marker for portal hypertension in patients with liver cirrhosis.

Technical note for post processing of jugular venous pulse, central venous pressure and velocity trace

In this paper an original reasoning about the post processing elaboration of medical studies is presented. The aim is to suggest a method to extrapolate numerical information from clinical images. The here described elaboration is referred to ultrasound examination of internal jugular veins and central venous pressure (CVP) measures. Firstly, the operator has to collect clinical images following precise indications, then specific techniques are applied to analyze the stored data and extrapolate quantifiable measures. Analyzing the studies with ImageJ software, jugular venous pulse, velocity, CVP and electrocardiogram traces can be drown in detail. Then, significant details can be highlighted using Matlab software. Finally, using R software, the traces can be cropped, aligned and synchronized together. The obtained results allow the operator to compare different kinds of traces of the same subject, or the same type of traces between a particular group of subjects. Before using these contents, everyone is invited to verify the accuracy of assumptions, calculations and conclusions.

CHANGES OF LEFT ATRIAL APPENDAGE ORIFICE FOLLOWING PERCUTANEOUS LEFT ATRIAL APPENDAGE CLOSURE USING THREE-DIMENSIONAL ECHOCARDIOGRAPHY

Percutaneous left atrial appendage occlusion (LAAO) with the Watchman device is increasingly performed in patients with atrial fibrillation and long-term contraindications for anticoagulation. Changes of LAA orifice size following LAAO and its impact on left upper pulmonary venous (LUPV) velocities

Significantly enlarged varix in the free-loop of the umbilical cord during the second trimester

Abstract Objectives Umbilical cord varix is an abnormal dilatation of the umbilical vein. There are two types of umbilical venous varix, of which the free-loop type is extremely rare, and the prognosis and etiology are unclear. In this report, we present a case of a significantly enlarged varix in the free loop of the umbilical cord found in the second trimester. Case presentation Cesarean section was performed at 28 weeks’ gestation due to enlargement of the varix and rapidly increased umbilical venous velocity at the outlet of the varix. Neonatal blood tests revealed anemia and high concentrations of D-dimer, and they were considered to be due to clot formation inside the umbilical cord venous varix. The neonate received blood transfusion but other neonatal course was generally favorable. Thrombus formation in the enlarged varix was due to the constriction of the umbilical cord. Conclusions This case showed that the assessment of umbilical venous flow velocity can be used for estimating the constriction of the umbilical vein and for determining the timing of delivery.

Effects of graduated compression stockings, local vibration and their combination on popliteal venous blood velocity.

The purpose of this pilot study was to examine and compare the effects of graduated compression stockings, local vibration, and combined graduated compression stockings and local vibration on popliteal venous blood velocity. Twenty-four healthy subjects received four 15 min interventions (control, graduated compression stockings alone, local vibration alone, and combined graduated compression stockings and local vibration), while resting inactive in the prone position. Popliteal vein blood velocity was investigated before (PRE) and at the end (POST) of each intervention using Doppler ultrasound. At POST, peak velocity was reported to be 26.3 ± 53.5% (p < 0.05) greater for local vibration than control (CONT). Peak velocity was 46.2 ± 54.6% (p < 0.001) and 21.1 ± 37.6% (p < 0.01) higher for graduated compression stockings than CONT and local vibration, respectively. Graduated compression stockings + local vibration presented 64.1 ± 58.0% (p < 0.001), 38.4 ± 52.4% (p < 0.001) and 15.0 ± 31.6% (p < 0.05) greater values than CONT, local vibration and graduated compression stockings, respectively. This study demonstrated an increase in popliteal venous blood velocity after graduated compression stockings and local vibration application. Their combination provided the greatest effects.

Role of Non invasive Imaging in Characterisation of Soft Tissue Vascular Anomalies: Comparison of Ultrasound with Contrast Enhanced Magnetic Resonance Imaging

Introduction: Soft tissue vascular anomalies present a diagnostic challenge. In these anomalies, imaging is crucial for therapeutic planning and improvement of prognosis. Ultrasound (US) and Contrast-Enhanced Magnetic Resonance Imaging (CEMRI) are both widely utilised and are valuable imaging modalities, both having distinct advantages and limitations in evaluation of such lesions. Aim: To evaluate soft tissue vascular anomalies using US and CEMRI and assess their agreement in characterisation of these lesions. Materials and Methods: The prospective study included 75 patients with vascular anomalies evaluated by means of US and CEMRI: 71 underwent both US and MRI, three underwent US alone, and one patient underwent MRI alone. Patients of all ages were included. Lesions were characterised based on imaging findings and vascular perfusion characteristics. Histopathological evaluation was done in all patients. Receiver Operating Characteristic (ROC) analysis was used for differentiating data. The agreement of US and CEMRI with histopathological diagnosis were assessed using kappa statistics. Results: Among the soft tissue vascular anomalies, 17 were haemangiomas, 55 were vascular malformations and 3 were other vascular tumours. Majority of the lesions were venous malformations (n=26; 34.66%). A cut-off value of 17.5 cm/sec of peak venous velocity using Colour Doppler showed 100% sensitivity in differentiating Arterio-Venous Malformations (AVM) from haemangiomas using ROC curves. Agreement expressed as kappa was 0.884 (95% CI 0.794-0.973) for US and 0.923 (95% CI 0.850-0.996) for CEMRI demonstrating near perfect agreement with histopathology in both. Conclusion: The findings of this study indicate that both US and CEMRI are accurate in detection and characterisation of soft tissue vascular anomalies showing comparable level of agreement. US may be the preferred imaging modality as it is widely available, relatively inexpensive and non invasive. Contrast enhanced MRI may be reserved as a complementary technique in cases wherein lesion categorisation or extent is ambiguous during diagnosis.

Objective Assessment of Venous Pulse Wave Velocity in Healthy Humans

Central venous pressure and volume status are relevant parameters for characterization of a patient's hemodynamic condition; however, their invasive assessment is affected by various risks while non-invasive approaches provide limited and subjective indications. Here we explore the possibility of assessing venous pulse wave velocity (vPWV), a potential indicator of venous pressure changes. In eight healthy patients, pressure pulses were generated artificially in the leg veins by rapid compression of the foot, and their propagation was detected at the level of the superficial femoral vein with Doppler ultrasound. Changes in leg venous pressure were obtained by raising the trunk from the initial supine position by 30° and 60°. vPWV increased from 1.78 ± 0.06 m/s (supine) to 2.26 ± 0.19 m/s (60°) (p < 0.01) and exhibited an overall linear relationship with venous pressure. These results indicate that vPWV can be easily assessed, and is a non-invasive indicator of venous pressure changes.

Monitoring intra‐abdominal pressure after liver transplantation in children

IAH after LTX can impair perfusion and threaten graft viability. This study aimed to assess the feasibility of longitudinal IAP measurements as an IAH screening method in children after LTX. A cohort of 23 children with a mean age (range) 3.1 (3months-14years) who underwent LTX between May 2017 and February 2018 were evaluated retrospectively. Longitudinal IAP measurements were compared to bedside Doppler US monitoring data. In total, 425 IAP measurements and 257 US examinations were performed. The mean±SD (range) time expenditure for IAP measurement was 1.9±0.4 (0.5-3.2)minutes. The mean post-operative IAP was 7.9±3.6 (1-25)mmHg. IAH (IAP≥10mmHg) was noted in 102 (24%) of 257 measurements. Agitation had a significant impact on IAP (estimate: 9.3mmHg, CI: 6.72-11.97, P<.01). In patients with TAC, IAP was increased (6.7±2.1 vs 8.7±3.1mmHg, P=.02) while peak portal venous velocities decreased (38±27 vs 26±22cm/s, P=.03) after patch reduction. An abdominal compartment syndrome with severely impaired vascular flow was noted in one patient. Episodes of elevated IAP were noted in a large proportion of patients, underscoring the need for IAP monitoring in pediatric liver transplant recipients. The safety and low time expenditure associated with IAP measurement could be included easily into standard nursing procedures for these patients.