Jugular Blood Flow Research Articles

Unintentional intracarotid injections in the horse—15 cases (2010–2020)

SummaryBackgroundIntracarotid injections are a well‐recognised complication of jugular injections in the horse; however, little information is available about outcome and complications.ObjectivesThe aim of this study was to describe venipuncture techniques and short‐ and longer‐term complications related to intracarotid injections.Study designCase series.MethodsThe survey was distributed through the American College of Veterinary Internal Medicine (ACVIM) mailing list and a veterinary social media site. Data collected in the questionnaire included injection technique, drug administered, personnel performing the injection, clinical signs and short‐ and longer‐term complications.ResultsAccidental intracarotid injections were most commonly performed by veterinarians (n = 9/13). The majority of reported accidental intracarotid injections occurred during routine sedation in healthy horses (n = 8/13) and occurred when the jugular vein was accessed at the middle jugular groove (n = 6/13). Most events occurred while using longer needles (1.5 inches; n = 10/13) of 20G calibre (n = 9/13), attached to the syringe (n = 11/13) and against jugular blood flow (n = 11/13). Short‐term injuries included superficial abrasions (n = 13/13) and cardiac ailments (3/13). One of the 15 horses described in this report died. Longer‐term complications were not reported for the remaining 14 horses.Main limitationsPotential selection, recall and response bias and putative risk factors identified cannot be correlated with an increased risk of carotid injection without a control group.ConclusionAccidental intracarotid injections led to seizures but rarely resulted in death of the case. Premonitory clinical signs occurred while or soon after injection and can be used for early identification of this inadvertent injection and to establish safety measures for the horse and handlers.

Abstract 439: Using the Time Interval Between R-Wave Detection and Maximum Compression Pressure to Target and Validate Delivery of Synchronized Chest Compressions During Pseudo Electro-Mechanical Dissociation

Introduction: The treatment of pseudo electro-mechanical dissociation (P-EMD) with standard chest compressions leads to some compressions that interfere with blood flow created by ventricular contraction and others that are synergistic. We have previously reported that the hemodynamics generated by standard chest compressions (StdCPR) depended on the time interval between the R-wave and the maximum compression pressure (t_int). Our goal was to use the t_int to identify the optimal timing for compression synchronization and to validate the delivery of synchronized chest compressions. Methods: Eight animals underwent surgical preparation and were exposed to hypoxia to induce P-EMD. The treatment period was divided into eight 45 sec epochs during which the P-EMD was left untreated or was treated with StdCPR or chest compressions synchronized to the R-wave in the ECG (SyncCPR). For each heart beat t_int was calculated as t peak AOP - t Rwave , blood pressures were averaged, and blood flows were integrated. 1,598 chest compressions were analyzed. The location of local extrema in hemodynamic parameters as a function of positive t_int values were identified recursively by dividing the range of t_int values into increasing numbers of bins and determining which bin had the highest mean value. Results: Blood flows and pressures exhibited a non-linear dependence on t_int. The maximum CPP occurred at t_int = 90 ±2.3 ms. The maximum aortic pressure occurred at t_int = 70 ±2.3 ms. The minimum right atrial pressure occurred at t_int = 280 ±2.3 ms. The maximum carotid blood flow occurred at t_int = 100 ±2.3 ms. The maximum jugular blood flow occurred at t_int = 400 ±2.3 ms. Unsynchronized chest compressions resulted in a t_int of -21 ± 170 ms. Synchronized chest compressions resulted in a t_int of 119 ± 13 ms. Conclusions: Local maxima and minima during StdCPR were identified in several hemodynamic parameters, but the extrema were not perfectly co-located. It appears that a t_int of 90-100 ms could be optimal. SyncCPR were delivered at 119 ms, which is not far from the local maxima observed for CPP and carotid blood flow.

Abstract 139: Impedance Threshold Device and Active Decompression Improve Hemodynamics in a Swine Model of Prolonged CPR

Introduction: Cardiopulmonary resuscitation with the impedance threshold device and active decompression (ITD-ACD CPR) has been shown to improve chest compression generated blood flow relative to standard chest compression. Using our high-fidelity swine model of cardiac arrest treated with prolonged mechanical chest compression (MCC) we studied the effect of different lift heights (amount of lift above the natural zero point of the sternum) during active decompression. Methods: CPR was performed on six domestic swine (~30 kg) using standard physiological monitoring. Flow was measured in the abdominal aorta, inferior vena cava (IVC), right common carotid and external jugular, and left femoral artery. Ventricular fibrillation (VF) was electrically induced. MCC were started after ten minutes of VF. Four MCC waveforms were used: Standard CPR (2”, 100 CPM), and ITD-ACD CPR (2”, 80 CPM) with 0.5”, 1.0”, and 1.5” lift past the zero point. MCC waveforms were changed every 2 min in a crossover design and delivered for 56 minutes. Data were analyzed in CPR cycles which included four epochs of CPR, one of each waveform, constituting 8 minutes of compressions. Results: Lift height had a significant (p<0.05) effect on carotid and jugular blood flow. Lift heights of 1.0 and 1.5” generated significantly more carotid blood flow in all 7 CPR cycles. A lift height of 1.5” generated significantly more jugular blood flow over all 7 CPR cycles. The interaction between duration of CPR and Jugular blood flow previously observed using this animal model was not observed. Carotid and jugular blood flow as a function of waveform and CPR cycle are shown in the figure. Conclusions: ITD-ACD CPR improved carotid and jugular blood flows, suggestive of improved cerebral perfusion. A lift height of 1.5” was required for significant improvement of jugular blood flows, while ITD-ACD CPR provided significantly better carotid blood flow than standard CPR at all lift heights.

Technical note: A method for quantification of saliva secretion and salivary flux of metabolites in dairy cows1

Salivary flow and net jugular flux of metabolites were studied during resting and rumination in 3 lactating dairy cows (BW 548 ± 17.2 kg, days in milk 113 ± 4 d). The method was based on the concentration difference between arterial and jugular blood, and jugular blood flow measured by downstream dilution of p-aminohippuric acid (pAH). Cows were surgically prepared with a permanent arterial catheter in A. intercostales dorsales before the trial. On sampling days, cows were prepared with left and right side jugular, and ear vein catheters for blood sampling and infusion of pAH, respectively. Blood was sampled simultaneously from the 2 jugular veins and artery during periods of rest and rumination. Secretion of saliva was set equal to the net water extraction calculated from the increased hemoglobin concentration in jugular blood compared with arterial blood. Arterial and jugular blood flow summed for both sides of the head doubled (P < 0.001) during rumination (437 ± 19, 424 ± 18 L/h, respectively) compared with resting (210 ± 19, 202 ± 18 L/h, respectively), consequently doubling the saliva secretion (P < 0.001, resting = 7.6 ± 0.8 L/h, rumination = 13.8 ± 0.8 L/h). The extraction of inorganic phosphate (Pi) from arterial blood during resting periods was greater compared with rumination (P = 0.004; resting = 21.7% ± 0.9%; rumination = 15.6% ± 0.9%), resulting in a greater Pi concentration in saliva secreted during resting. The concentrations of Pi in saliva were 4.5 ± 0.3 and 3.7 ± 0.3 times the arterial concentration during resting and rumination (P = 0.09), respectively. The urea concentration in saliva was 0.63 ± 0.04 times the arterial level, showing that urea is less efficiently transferred from blood than water, resulting in a greater numerical urea concentration in jugular compared with arterial blood. The water extraction method presented in the present paper offers an alternative way of estimating saliva secretion without the chewing activity constraints associated with other methods, for example, allowing for determination of saliva flow during rumination.

Internal jugular vein valve incompetence in COPD and primary pulmonary hypertension

Under physiologic conditions, intact internal jugular vein valves (IJVVs) efficiently prevent retrograde venous flow during intrathoracic pressure increase. Chronically elevated central venous pressure found in patients with chronic obstructive pulmonary disease (COPD) and primary pulmonary hypertension (PPH) might lead to IJVV incompetence (IJVVI). The aim of this study was to analyze the prevalence of IJVVI in patients with COPD and PPH using duplex sonography (DUS). We included 30 COPD patients, 5 PPH patients, and 100 healthy controls in the study. IJVVI was diagnosed if retrograde jugular blood flow was seen on DUS during a Valsalva maneuver. Retrograde venous flow intensity was evaluated and graded according to extent and duration of reflux. IJVVI was found in 18 (60%) COPD patients and in all 5 (100%) PPH patients, which was significantly different from the controls (27%; p < 0.005). The intensity of venous retrograde flow correlated with the pulmonary artery pressure. Compared with healthy controls, COPDand PPH patients demonstrated a significantlygreater prevalence of IJVVI, which seems to be caused by the elevated central venous pressure. These patients may be at higher risk to develop central nervous system diseases related to cerebral outflow obstruction.

Increased brain serotonin turnover in panic disorder patients in the absence of a panic attack: Reduction by a selective serotonin reuptake inhibitor

Since the brain neurotransmitter changes characterising panic disorder remain uncertain, we quantified brain noradrenaline and serotonin turnover in patients with panic disorder, in the absence of a panic attack. Thirty-four untreated patients with panic disorder and 24 matched healthy volunteers were studied. A novel method utilising internal jugular venous sampling, with thermodilution measurement of jugular blood flow, was used to directly quantify brain monoamine turnover, by measuring the overflow of noradrenaline and serotonin metabolites from the brain. Radiographic depiction of brain venous sinuses allowed differential venous sampling from cortical and subcortical regions. The relation of brain serotonin turnover to serotonin transporter genotype and panic disorder severity were evaluated, and the influence of an SSRI drug, citalopram, on serotonin turnover investigated.Brain noradrenaline turnover in panic disorder patients was similar to that in healthy subjects. In contrast, brain serotonin turnover, estimated from jugular venous overflow of the metabolite, 5-hydroxyindole acetic acid, was increased approximately 4-fold in subcortical brain regions and in the cerebral cortex (P < 0.01). Serotonin turnover was highest in patients with the most severe disease, was unrelated to serotonin transporter genotype, and was reduced by citalopram (P < 0.01). Normal brain noradrenaline turnover in panic disorder patients argues against primary importance of the locus coeruleus in this condition. The marked increase in serotonin turnover, in the absence of a panic attack, possibly represents an important underlying neurotransmitter substrate for the disorder, although this point remains uncertain. Support for this interpretation comes from the direct relationship which existed between serotonin turnover and illness severity, and the finding that SSRI administration reduced serotonin turnover. Serotonin transporter genotyping suggested that increased whole brain serotonin turnover most likely derived not from impaired serotonin reuptake, but from increased firing in serotonergic midbrain raphe neurons projecting to both subcortical brain regions and the cerebral cortex.

Cerebral blood flow in critically ill cardiac patients: effects of vasoactive drug therapy

The introduction of the thermodilution technique (TD) in measuring cardiac output (CO) and coronary sinus blood flow has suggested the application of the same technique into measuring CBF which has been validated by several methods using transcranial Doppler and Xenon inhalation clearance curves. The present work is intended to assess the effect of two vasoactive drugs on CBF in 20 critically ill patients (12 males, 8 females, mean age: 5.86 ± 9.46) all having CHF due to dilated cardiomyopathy. Following clinical examination all patients were subjected to haemodynamic evaluation including central venous line, arterial cannulation and jugular vein catheterization. The latter was performed using Baim coronary sinus catheter directed towards the right jugular vein under fluroscopic guidance up to the bulb of internal jugular vein. Jugular blood flow (JBF) was measured by constant infusion of ice cold (5%) dextrose solution and recorded digitally on a Baim coronary sinus computer. Haemodynamic measurements including CBF were made at rest and repeated following infusion of noradrenaline (NA) in incremental doses sufficient to raise BP by one third of the basal reading. An average of three readings were taken. NA was discontinued and after 20 min the same method was repeated after dobutamine infusion given in a dose of 10 μg/kg/min for 20 min. Compared to basic measurements, NA significantly reduced CBF by 22.4 ± 4.79% in 13 patients with simultaneous increase in CVR by 106.73 ± 29.0%, NA increased CBF by 40.46 ± 12.0% in seven patients with simultaneous decrease of CVR by 13.7 ± 6.2%. It also increased systemic vascular resistance by 24.9 ± 2.76%, P < 0.0001. On the other hand dobutamine has led to an increase in CBF by 56 ± 12% in 11 patients with simultaneous decrease in CVR by 22 ± 6.31%. It decreased the CBF by 38.1 ± 11.8% in four patients with simultaneous increase in CVR by 130.68 ± 70.01%, and a decrease SVR by 21 ± 5%, P < 0.0359. In conclusion, vasoactive drugs commonly used in critically ill cardiac patients have different effects on cerebral blood flow. Despite the beneficial effects obtained from using NA in increasing perfusion pressure and cardiac output, the adverse effects on CBF are an obvious limitation to its use as a monotherapy, compared to dobutamine which besides augmenting CO improves dramatically CBF.

Measurement of Cerebral Oxyhaemoglobin Saturation and Jugular Blood Flow in Term Healthy Newborn Infants by Near-Infrared Spectroscopy and Jugular Venous Occlusion

Data of cerebral haemodynamics and oxygenation are important for optimal treatment and prognosis in neonatal intensive care. Mostly premature and asphyxiated infants have been examined, but near-infrared spectroscopy (NIRS) allows estimations in healthy term newborns. In this study, cerebral venous saturation (CVsO₂) and jugular blood flow (JBF) was estimated in 11 healthy term newborns. Mean CVsO₂ was 64.12 ± 4.6%, which conform with expectations. Mean JBF was only 6.1 ml/100 g/min, which is unacceptably low compared to earlier published data. We discuss physiological and methodological aspects and conclude that the combination of NIRS and venous occlusion appears to be a reliable method for estimation of CVsO₂ in normally healthy newborns, whereas the reason for the failure of the method for estimation of JBF is unclear.

Jugular venous blood flow velocity waveforms in human fetuses between 20 and 42 weeks of pregnancy.

The goal of the study was to measure the blood flow parameters of the fetal internal jugular vein during the second half of normal pregnancy using Doppler ultrasound. Jugular blood flow was analyzed in 95 normal singleton fetuses between 20 and 42 weeks gestation. Color and pulsed Doppler ultrasound was used to obtain jugular venous waveforms at the level of the mid-neck. Peak velocities, ratios of velocities, and time-averaged maximum velocities were measured. Jugular venous waveforms in healthy fetuses consist of three phases--the first forward peak occurs during ventricle systole; the second forward peak occurs during early diastole and the third peak occurs during atrial contraction. Forty-eight percent of the fetuses demonstrated absent flow during atrial contraction; 32% of fetuses demonstrated forward flow during atrial contraction and finally 20% of fetuses demonstrated flow reversal during atrial contraction. The reported jugular venous profile may serve as a foundation for future studies of jugular blood flow in high risk fetuses.

Estimation of Cerebral Blood Flow at Bedside by Continuous Jugular Thermodilution

The Kety-Schmidt technique can be regarded as the reference method for the measurement of cerebral blood flow (CBF). However, the method is somewhat cumbersome for routine use in the intensive care unit (ICU) at the beside. The continuous thermodilution technique developed many years ago for the measurement of coronary sinus blood flow can be applied for the measurement of jugular blood flow (JBF). However, the measurement of JBF by thermodilution has never been validated using the Kety-Schmidt reference method. We first validate the continuous thermodilution in vitro by comparison with a volumetric flow. The thermodilution method is accurate for flows between 50 and 900 ml min-1 with a mean difference volumetric-thermodilution flow of -1 +/- 18 ml min-1 (mean +/- SD), and precise with a coefficient of variability ranging between 1.21% and 2.50%. In vivo accuracy was assessed by comparing in 15 comatose patients CBF measured using the Kety-Schmidt (CBFKS) method and estimated from JBF measured by thermodilution (CBFTH) at four levels of arterial PaCO2 (25, 30, 35, and 40 mm Hg). The mean difference CBFKS-CBFTH is -0.9 +/- 3.6 ml min-1 100 g-1. In vivo precision of the method was good, with a coefficient of variability of 4.1% in mean. We conclude that jugular continuous thermodilution technique is a reliable method for estimating CBF at the bedside. This technique allows repeated measurements jugular bulb blood sampling for brain metabolic studies.

Cerebral metabolism and its relationship with sympathetic nervous activity in essential hypertension

To examine Dickinson's hypothesis in mild essential hypertension, in which neurogenic mechanisms are believed to be particularly relevant, by combining measures of cerebral oxygen consumption with the concurrent assessment of sympathetic nervous activity. Twenty-five untreated essential hypertensive subjects and 28 healthy age-matched volunteers underwent direct blood sampling using percutaneously inserted catheters advanced into the internal jugular vein, with cerebral blood flow scans to differentiate between cortical and subcortical venous drainage of the brain. Venoarterial blood gas measurements and internal jugular vein blood flows were used to calculate cerebral respiratory quotients and cerebral oxygen utilization. The total body rate of noradrenaline spillover into plasma was measured to assess relationships between cerebral oxidative metabolism and sympathetic nervous activity. Compared with controls, the hypertensive subjects exhibited reductions in internal jugular vein blood flow (482 +/- 29 versus 410 +/- 15 ml/min), cerebral oxygen consumption (27 +/- 2 versus 23 +/- 1 ml/min) and cerebral oxygen supply (93 +/- 6 versus 78 +/- 3 ml/min). The cerebral respiratory quotients were identical (1.00 +/- 0.04 in normotensives and 0.98 +/- 0.03 in hypertensives). Technetium blood flow scans revealed that the reductions in internal jugular blood flow and cerebral oxygen consumption in the hypertensive patients were confined to cortical brain regions. Cortical blood flow was quantitatively linked to the matching respiratory quotient and oxygen consumption, neither of which bore any relation to the level of sympathetic nervous activity. The spillover of noradrenaline into the plasma for the body as a whole did not differ between the two groups. In accord with Dickinson's hypothesis, we have established a reduction in internal jugular vein blood flow and cerebral oxygen utilization in hypertension. These reductions were confined to cortical brain regions. However, cerebral respiratory quotients in our hypertensive study group were no different from those in our controls, suggesting that glucose remained as the major cerebral metabolic substrate in hypertension. We were not able to establish a link between cerebral metabolism and blood pressure or sympathetic nervous activity in mildly hypertensive patients.

Management of the Jugular Bulb During Lateral Skull Base Surgery

The intraoperative management of a patent jugular bulb presents a formidable challenge during the treatment of lateral skull base lesions. Whether to preserve, partially occlude, or completely sacrifice this critical structure is a decision best made following a multifactorial analysis of preoperative clinicoradiographic data, tumor histopathology, and intraoperative findings. Twenty-six patients with tumors requiring dissection near a patent jugular bulb were reviewed. Ten patients had superior neck tumors, nine had primary temporal bone lesions, and seven presented with recurrent parotid malignancies. The most common clinical manifestations were headache and vocal cord paralysis and the most significant radiographic finding was the presence of a mass at the styloid base. Jugular bulb patency was preserved in six patients, partially maintained in seven, and was sacrificed in 13 individuals. This article focuses on the clinicoradiographic findings in patients with neoplastic jugular foramen encroachment, but preserved jugular blood flow. Surgical technique will be detailed through selected case presentations and the management of lower cranial nerve injuries will be reviewed.

Jugular blood flow in calves after head-only electrical stunning and throat-cutting

Jugular flow was measured after head-only electrical stunning and gash cutting in 12 calves less than a week old. Jugular flow was assumed to provide a crude measure of cerebral perfusion during exsanguination. In 10 animals the average amount of jugular blood collected within 1–2 min of throat-cutting was the equivalent of a total cerebral blood flow of 3·6 ml/min/100 g ± 1·4 SD or 4·8% of normal. In two animals the jugular flow was increased to 39% and 22% of normal cerebral flow. All animals had strong retrograde flow from the head ends of the cut carotid arteries. The dynamics of cerebral blood perfusion are discussed with reference to systemic arterial blood pressure and spontaneous cortical electrical activity, and some potentially fruitful areas of research on the humaneness of halal slaughter of cattle are proposed.

Effect of feeding on jugular venous blood flow in the normal newborn infant.

Jugular venous occlusion plethysmography was used to measure jugular blood flow in 47 infants; this was done at varying times after the end of a feed. Jugular blood flow was found to be lower, by about 30%, during the first postprandial half hour than at any other time up to 2 hours postprandially. In 2 infants longitudinal studies were performed in relation to several feeds, and postprandial reductions in blood flow of a similar magnitude were found. Aspects of the venous occlusion technique are discussed. It is concluded that feeding in healthy neonates is associated with a subsequent reduction in jugular blood flow, and possible mechanisms for this phenomenon are discussed.

An estimation of intracranial blood flow in the new‐born infant.

1. A non-invasive method for the estimation of the intracranial blood flow of the new-born infant is described, and results obtained with it are presented. 2. The technique is a novel application of the principle of blood flow measurement by venous occlusion plethysmography. It is possible to apply a plethysmographic technique to the neonatal cranium because the presence of open sutures between the component bones permits small, but readily measurable, changes in intracranial volume to occur. 3. Skull volume changes are calculated from changes in the occipito-frontal circumference of the cranium as recorded and measured with a mercury-in-Silastic strain gauge. 4. The jugular veins in the baby's neck are occluded by finger pressure and there follows an increase in skull volume, which is rapid at first, but which decreases exponentially as venous drainage diverts to non-occluded channels such as the vertebral venous plexus. At the instant of jugular occlusion the rate of skull volume increase is representative of the rate of flow in the jugular vessels prior to occlusion, and so provides an index of the relative magnitude of the intracranial blood flow. The method thus allows changes in intracranial blood flow to be followed. When occlusion is released cranial volume decreases, initially rapidly, but slowing exponentially as resting volume is regained. 5. A theoretical model of the events occurring during the inflow and outflow phases has been developed, and a formula derived which allows an estimation to be made of the flow of blood through uncompressed channels. The measured value of jugular blood flow can then be augmented to an estimate of total intracranial flow. 6. The mean cerebral blood flow of sixteen normal babies was estimated to be 40 ml. 100 g-1.min-1 (S.D. = +/- 11.63).