Use of the internal jugular vein for carotid patch angioplasty

The internal jugular vein is an excellent source of autogenous tissue for carotid artery reconstruction because of its availability in the operative incision, adequate size, and ability to be harvested without morbidity. For 153 of 453 consecutive carotid reconstructions, the durability of the internal jugular vein (n = 76) and the greater saphenous vein (n = 77) as a patch angioplasty was compared. Mean postoperative follow-up was 17 months (1 to 52 months). The vein-patched carotid-bifurcation was studied by means of duplex ultrasonography to assess patency, detect restenosis, and measure cross-sectional diameter during systole. No carotid bifurcation occluded after operation. No ruptures or aneurysmal dilatations of the vein patches were observed. The maximum diameter (mean +/- SD) of the carotid patch angioplasties constructed with internal jugular vein (9.4 +/- 1.9 mm) was similar to patches made with greater saphenous vein (9.6 +/- 1.7 mm). In 95 patients serial duplex examinations demonstrated maximum diameter changes of the vein-patched internal carotid artery ranging from an increase of 3.5 mm to a decrease of 3.0 mm. Asymptomatic restenosis (greater than 50% diameter reduction) was detected in 2/95 (2.1%) patients. Because of the premium placed on the saphenous vein for peripheral arterial reconstruction and coronary artery bypass grafting, the ipsilateral internal jugular vein should be used more frequently for carotid patch angioplasty.     

Right internal jugular vein venography in infants and children

We obtained venograms of the right internal jugular vein (RIJV) in 105 infants and children with congenital heart disease during cardiac catheterization. No major anomalies were found in the course of the RIJV. The diameter of the RIJV tended to increase with the patient's age, weight, and height. However, some disproportionately small vessels were seen in 8% of the patients. The depth from the skin to the RIJV varied from 2.5 to 20 mm and did not significantly correlate with age, weight, or height. Confirmation of the diameter or the depth of the RIJV by venography may facilitate clinical decisions and may be useful for performing percutaneous cannulation. IMPLICATIONS: We obtained venograms of the right internal jugular vein in children with congenital heart disease. Generally, the diameter increased with the patient's body size, but disproportionately small vessels were seen in 8% of the patients. Preoperative internal jugular venography may facilitate identifying those patients.     

Internal jugular vein cannulation guided by ultrasonography in pediatric patients undergoing cardiovascular surgery

BACKGROUND: Central venous catheterization is essential for the anesthetic management of operations for congenital heart diseases. We prospectively examined the usefulness of ultrasonography in internal jugular vein catheterization in infants. METHODS: Internal jugular vein cannulation was guided using an ultrasound image scanner in 96 pediatric cardiac patients. We investigated the rate of successful catheterizations, the number of attempts, the time from venipuncture to wire insertion, and the laterality of internal jugular vein diameters. RESULTS: The success rate in all 96 patients was 95.8% with no carotid artery puncture. Patients younger than 12 month of age had success rates of 90%. In patients younger than 1 month of age and with weights less than 3.4 kg, the success rate was 76.9%. The time from venipuncture to proper wire insertion in the first attempt (55.2%) was 50.8+/-18.9s; 157.3 +/-56.4s for second attempt (18.8%) ; 285.7+/-165.7s for third attempt (7.6%) ; 346.0+/-98.4s for fourth attempt (5.5%) : and 510.0+/-98.4s for fifth attempt (2.1%). The time requited was 1404.5+/-518.4s for attempts that required more than seven passes. Cannulations in four cases were unsuccessful because the image of the internal jugular vein was difficult to visualize. The left internal jugular vein diameter was larger than the right in 40 cases. In three unsuccessful cases, the diameter was less than 4.5 mm. CONCLUSIONS: Internal jugular vein cannulation guided by ultrasonography can be performed safely and quickly in pediatric patients.     

Experiences with Swan-Ganz-catheter placement in the external jugular vein

Clinical experience concerning the placement of Swan-Ganz catheters (SGC) via the external jugular vein is presented. After puncture of either the right or left external jugular vein, placement of SGC was possible in 90 per cent of patients. Compared to techniques involving puncture of the internal jugular vein this method has less complications. The placement of 167 SGC could be done without any problems, thus proving that the external jugular vein is a safe way of insertion. The external jugular vein as a primary route can be recommended if the vein is visible, especially in cases where puncture of the internal jugular vein may be difficult and could only be performed with an increased risk of complications.     

An evaluation of external jugular vein patch angioplasty after carotid endarterectomy

Seventy-six patients had 91 internal carotid endarterectomies closed with patch angioplasty. There were 36 redo and 55 primary procedures. External jugular vein was used as the patch material in 38, facial vein in nine, Dacron in seven, polytetra flour ethylene (PTFE) in nine, and saphenous vein in 28 operations. There were no perioperative deaths. Five patients required reoperation, but only one required replacement of a defective facial vein. There were five postoperative strokes, but two were related to a contralateral occlusion. Two of the three ipsilateral strokes had a temporary indwelling shunt. Only one patient returned with recurrent neurologic symptoms. Five other restenoses of greater than 75 per cent were noted in three patients. One false aneurysm occurred three months after an external jugular vein patch angioplasty. External jugular vein, although requiring careful handling, is conveniently located in the operative field, does not appear to be associated with increased complications, has excellent long-term results, and allows preservation of the saphenous vein for other bypass surgery.     

Influence of vein size (diameter) on infrapopliteal reversed vein graft patency

We reviewed 239 infrapopliteal reversed greater saphenous vein graft bypasses placed for critical ischemia over a 7-year period to determine the influence of vein diameter on graft patency and limb salvage. Grafts were assigned to four groups based on the minimum external diameter measured during operation: less than 3.0 mm, n = 18; 3.0 mm, n = 59; 3.5 mm, n = 67; and greater than or equal to 4.0 mm, n = 145. A pattern of increasing graft patency and limb salvage among the four groups was noted as the minimum external diameter increased from less than 3.0 mm to greater than or equal to 4.0 mm. When compared to the larger grafts greater than or equal to 4.0 mm, primary graft patency was significantly lower both for less than 3.0 mm grafts (0% for less than 3.0 mm vs 65% for greater than or equal to 4.0 mm at 3 years, p less than 0.001) and for long (greater than 45 cm) 3.0 mm grafts (38% for long 3.0 mm vs 75% for greater than or equal to 4.0 mm at 2 years, p less than 0.005). All 3.5 mm and short (less than 45 cm) 3.0 mm grafts had patency rates similar to greater than or equal to 4.0 mm veins. Thus long 3.0 mm and all less than 3.0 mm reversed saphenous vein grafts should be considered at high risk for failure. Veins with fibrotic, thick-walled segments identified during operation (n = 19) had patency rates significantly lower than nonfibrotic veins (n = 270; p less than 0.01), and this may play a role in the failure of some less than 3.0 mm minimum external diameter vein grafts.     

Internal jugular vein versus external jugular vein anastamosis: implications for successful free tissue transfer

BACKGROUND: Microvascular free flaps are becoming the reconstructive option of choice for many head and neck defects. Many previous studies have examined factors predicting free flap survival. No study has compared differences in free flap survival when anastomosed to the internal or external jugular systems. METHODS: Retrospective review of all free flaps performed at an academic medical center by a single head and neck microvascular surgeon during the period July 1995 to December 1999. Flaps were closely monitored postoperatively and taken back to the operating room urgently for arterial insufficiency or venous congestion. RESULTS: On hundred fifty-six free flaps were performed during this time period. Sixty-five free flaps were anastomosed to the external jugular (EJ) vein and 86 to the IJ system (62 to the proximal common facial vein, 17 end-side on the IJ, and 7 to other branches). Five had either two venous anastomoses or were anastomosed to other veins and were excluded from statistical analysis. Six (4%) vascular thromboses occurred; 5 were venous and 1 arterial. Success by group was 99% for IJ anastomosis (1 arterial thrombosis) and 92% for EJ anastomosis (5 venous thromboses, p =.03). Urgent anastomotic revision and reperfusion salvaged 5 of the 6 flaps (overall success 99%). CONCLUSIONS: Although the overall success rate (96% success with 99% success with salvage) is comparable to other large series, microvascular free flaps anastomosed to the external jugular vein failed at a significantly higher rate than those anastomosed to the IJ system. This suggests that the IJ system should be used as a recipient vessel when feasible.     

Compression of the trachea by a hematoma caused by an internal jugular vein catheter

In a patient with thrombocytopenia, respiratory obstruction because of a hematoma occurred following internal jugular vein cannulation. This patient recovered completely after surgical intervention. With the following precautions in mind, puncture of the internal jugular vein in patients with coagulopathies has a high success rate and does not result in severe complications: Internal jugular vein cannulation by an experienced physician; optimal conditions for puncture by increasing venous pressure and diameter with slight Trendelenburg position and Valsalva maneuver in patients with spontaneous breathing, or positive end-expiratory pressure in patients with artificial ventilation; catheter insertion by the Seldinger technique; manual compression of the puncture site for 10-15 min; and vein puncture with ultrasonographic aid if possible.     

The effect of laryngeal mask airway insertion on the position of the internal jugular vein

A high-quality ultrasound system (Dyasonics Prisma) was used to study the effect of laryngeal mask airway insertion and cuff inflation on the position and relations of the internal jugular vein in eight healthy young patients undergoing elective surgery. On insertion of the laryngeal mask, with the cuff pre-inflated with 10 ml of air, some minor movement was discernible in the larynx. Neither the larynx nor surrounding structures changed significantly in position. However, on full inflation of the laryngeal mask cuff there was a more noticeable movement of the larynx, which visibly distended in an anterior direction. The mean anterior displacement was 0.8 cm (range 0.6–1.1 cm). There was no significant lateral displacement of the carotid artery or internal jugular vein and there was no significant compression of these structures. We conclude that in the presence of a laryngeal mask airway fixed landmarks such as the sternal notch and angle of the jaw should be used to identify the likely position of the internal jugular vein. Difficulty in cannulation may be experienced if the mobile laryngeal structures are used as landmarks.     

Respiratory jugular venodilation: its anatomic rationale as a landmark for right internal jugular vein puncture as determined by ultrasonography

OBJECTIVE: To reveal anatomic factors that determine the visibility of respiratory jugular venodilation, a landmark for right internal jugular vein puncture, in ventilated patients. DESIGN: Prospective observational study. SETTING: Single community hospital. PARTICIPANTS: Adult patients undergoing general endotracheal anesthesia. INTERVENTIONS: Anatomy of the right neck, including the carotid artery and internal jugular vein, was evaluated in a blind manner using 7.5-MHz ultrasonography in patients simulating the position for internal jugular vein puncture. Anatomic variables correlated with the visibility of respiratory jugular venodilation were analyzed. MEASUREMENTS AND MAIN RESULTS: Of 124 patients, respiratory jugular venodilation was observed in 94 patients (75.8%). Satisfactory quality of ultrasound image was obtained for all patients. The visibility of venodilation correlated with the extent of change of the vein size during a respiratory cycle but not with the end-expiratory or end-inspiratory vein diameter. These results indicated that there was no correlation between the vessel size and the visibility of venodilation, suggesting that it is rational to attribute the increased success rate of the respiratory jugular venodilation-guided puncture to accurate vein localization rather than to a larger target size. Among the demographic variables examined, body weight and obesity correlated with the visibility of venodilation, but age, gender, and height did not correlate. In obese patients, the respiratory change of the vein diameter was smaller, and the vein was deeper. CONCLUSIONS: The visibility of respiratory jugular venodilation does not correlate with the vein size but with the extent of its dynamic change during a respiratory cycle.     

Autogenous common facial vein or external jugular vein patch for carotid endarterectomy.

BACKGROUND: The purpose of this study was to determine whether common facial vein or external jugular vein are as good a vein patch as a saphenous vein for carotid patch angioplasty. METHOD: Retrospectively, 19 patients who underwent everted common facial vein or external jugular vein patch were compared with 199 patients who underwent saphenous vein patch carotid endarterectomy during 1989 to 1996. The two groups were compared clinically and by sonographic surveillance. The mean follow-up was 18+/-4 months for common facial vein/external jugular vein patients and 48+/-15 months for saphenous vein patch group. RESULTS: No significant differences in mortality or morbidity were observed among patients in whom everted common facial vein or external jugular vein was used as compared with saphenous vein. No bleeding, thrombotic event, dilation of the patch or aneurysmal degeneration and perioperative deaths occurred in either of the two groups. Duplex surveillance studies showed no significant difference in recurrent moderate (50-79%) and severe (80-99%) stenosis. CONCLUSION: Everted common facial vein or external jugular vein patch was comparable to other vein patches. This eliminates the comorbidity of groin incision. Also, using everted common facial vein or external jugular vein as vein patch saves saphenous vein to be used for other vascular procedures, such as coronary artery or lower extremity bypass.     

New microvenous anastomosis model for microsurgical training: external jugular vein

In microsurgical training, the femoral vein is used frequently for a microvenous anastomosis model. But the femoral vein in the rat does not completely simulate the human vein because of its thin wall, fragility, and tendency to collapse. These anatomic characteristics cause some difficulty in carrying out anastomoses in microsurgery training particularly for beginners. The authors propose the external jugular vein of the rat for microsurgical training in microvenous anastomoses. In 10 Wistar rats, the anatomy of the external jugular vein was studied by dissection and histology. Anatomic dissections demonstrate that the external jugular vein has an average diameter of 1.9 mm (range: 1.6 to 2.1 mm) without tendency to collapse. The vein is easily dissected without any accompanying anatomic structure for an average segment of 45 mm, allowing effortless approximator clamp placement. Comparison of its cross section with that of the femoral vein and other previously described models by light microscopy and scanning electron microscopy reveals a larger diameter and much thicker vessel wall with a prominent tunica media and adventitia. Based on the anatomic findings in 20 rats, the external jugular vein was anastomosed with end-to-end standard microsurgical technique using 8-0 (n = 10) and 10-0 (n = 10) nylon sutures. Results indicate a 100 percent patency rate immediately after the anastomosis for the two subgroups and 100 percent and 90 percent patency rates 1 week after the procedure for the 10-0 and 8-0 nylon suture groups, respectively. This model presents some advantages: the vein is easily dissected with the naked eye without using the operating microscope because it is the largest vein among the superficially located veins in the rat, and has a thick vessel wall without tendency to collapse. The operative area allows for training inbilateral microsurgical anastomoses using a single skin incision and is safe from autocannibalization. The model simulates clinical microvenous anastomosis better because of its similarities to human large diameter flap veins.     

Migration of a distal ventriculoperitoneal shunt catheter into the internal jugular vein and heart through the external jugular vein: case report

A 6-year-old boy had undergone ventriculoperitoneal (VP) shunt for acute hydrocephalus because of a brain tumor at the age of 11 months, and presented with vomiting and somnolence after the shunt malfunctioned 6 days after VP shunt reconstruction, during which the right external jugular vein was injured during the tunneling process and the peritoneal catheter was not fixed to the peritoneum with a purse string suture. Radiography revealed an abnormal route of the peritoneal catheter, suggesting that the distal VP shunt catheter had migrated into venous vasculature through the right external jugular vein. Computed tomography revealed that the peritoneal catheter had migrated into the internal jugular vein and the right atrium. At surgery, the peritoneal catheter was exposed through a small incision on the subclavicular region, was easily extracted from the internal jugular vein and the heart as there was no coiling or adhesion of the distal catheter to the vascular tissues, and was repositioned into the peritoneum with weak fixing between the subcutaneous tissues of the right subclavicular region and the right abdominal rectus muscle fascia as a temporary emergency measure. Peritoneal shunt migration into the internal jugular vein and the heart through the external jugular vein can be lethal because of pulmonary infarction or arrhythmia, and must be detected as soon as possible. Periodic follow-up radiography should be scheduled after VP shunt placement, even in the absence of symptoms.     

Venography at insertion of tunnelled internal jugular vein dialysis catheters reveals significant occult stenosis.

BACKGROUND: Tunnelled catheters are widely used to provide vascular access for haemodialysis. Percutaneous insertion of these catheters requires large calibre tissue dilators with the potential to cause trauma to central veins, particularly if anatomical abnormalities are present. METHODS: We evaluated the use of venography to identify central vein anatomical abnormalities in 69 consecutive patients undergoing percutaneous placement of tunnelled right internal jugular vein catheters. The internal jugular vein was entered under ultrasound guidance and venography was performed prior to insertion of a guide-wire. Images were evaluated on-screen by the operator and a decision made regarding the need for additional fluoroscopy during insertion of the catheter. RESULTS: In 29 cases (42%), venography showed evidence of unexpected stenosis and/or angulation of the central veins of sufficient severity to warrant additional fluoroscopy during insertion of the dilators, or abandonment of the procedure. Patients who had previously had tunnelled internal jugular catheters had more than double the incidence of such abnormalities than those who had not [15/23 (65%) vs 14/46 (30%); P = 0.009]. In two patients the procedure was abandoned due to severe stenosis. No patient suffered central vein trauma or pneumothorax. There were no adverse reactions to contrast injection. CONCLUSIONS: Venography performed immediately prior to tunnelled internal jugular dialysis catheter insertion detects unexpected, clinically significant anatomical abnormalities of the central veins in a substantial proportion of patients, particularly those with a history of previous tunnelled catheter insertion. We suggest that the use of venography may help to minimize the risk of complications from this procedure.     

Comparison of three techniques for internal jugular vein cannulation in infants

Central venous cannulation allows accurate monitoring of right atrial pressure and infusion of drugs during the anaesthetic management of infants undergoing cardiopulmonary bypass. In this prospective, randomized study, we compared the success and speed of cannulation of the internal jugular vein in 45 infants weighing less than 10 kg using three modes of identification: auditory signals from internal ultrasound (SmartNeedle, SM), external ultrasound imaging (Imaging Method, IM) and the traditional palpation of the carotid pulsation and other landmarks (Landmarks Method, LM). The cannulation time, number of attempts with LM and SM techniques were greater than those with IM technique. The incidence of carotid artery puncture and the success rate were not significantly different among the three groups. In infants, a method based on visual ultrasound identification (IM) of the internal jugular vein is more precise and efficient than methods based on auditory (SM) and tactile perception (LM).     

The influence of the Univent endotracheal tube on internal jugular vein cannulation

This prospective clinical investigation assessed the effect of placement of a Univent tube on the anatomy of the internal jugular veins and the success of cannulation of the left internal jugular vein. After obtaining informed consent, 48 adult patients were enrolled. Of these, 42 patients were eligible and were divided into two groups: Univent tube (group U, n=21) and wire enforced endotracheal tube (group C, n=21). The Univent tube group were having a left thoracotomy. Using horizontal ultrasound scans just above the thyroid gland, the internal jugular vein was visualized and measured before and after Univent placement. The number of needle passes necessary to cannulate the left internal jugular vein in the two groups was also compared. Univent tubes were associated with lateral displacement of the right carotid artery and internal jugular vein on the convex side of the Univent tube, with compression of the right internal jugular vein by the artery, resulting in a kidney-shaped cross-section of the vein. On the left (concave side of the tube), the neck was indented, the sheath of the left carotid artery was displaced medially, and the left internal jugular vein distorted to an ellipse. There was a significant increase in the lateral diameter and a decrease in the cross-sectional area of the left internal jugular vein (t-test, P < 0.05). The first attempt at cannulation of the left internal jugular vein failed significantly more often in the Univent group (13/21 vs 5/21 in group C, Chi-square 6.22, P=0.025). Cannulation of the internal jugular vein before placement of the Univent tube, or placement with ultrasound guidance is suggested.     

Respiratory jugular venodilation: a new landmark for right internal jugular vein puncture in ventilated patients

OBJECTIVE: To report a new technique for right internal jugular vein puncture using respiratory jugular venodilation as a landmark for vein location. DESIGN: Prospective observational study. SETTING: Single community hospital. PARTICIPANTS: Two hundred patients undergoing right internal jugular vein cannulation under general anesthesia. INTERVENTIONS: Catheter placement was attempted using respiratory jugular venodilation as the primary landmark. When it was not applicable, an alternative technique using the carotid pulse as a landmark was used. MEASUREMENTS AND MAIN RESULTS: Visibility of the venodilation, the number of needle passes, the success rate, and the incidence of arterial puncture were analyzed. Respiratory jugular venodilation was observed in 158 patients (79%). In this group of patients, the jugular vein was cannulated at the first attempt in 83.5% of patients, and arterial puncture occurred in one patient (0.6%). In the remaining 42 patients (21%) lacking the visible venodilation, catheter placement was accomplished at the first attempt in 42.9% of patients (p<0.01 v. the venodilation-visible group), and 4 patients (9.5%) suffered arterial puncture (p<0.01). The overall incidence of arterial puncture was 2.5%. The success rate of cannulation (within four needle passes and no arterial puncture) was 98.1% in the venodilation-visible patients and 73.8% in the others (p<0.01), with the overall success rate of 93%. CONCLUSIONS: Respiratory jugular venodilation can be identified in a large proportion of ventilated patients. This experience suggests that respiratory jugular venodilation could be favorably used as the primary landmark for right internal jugular vein puncture in anesthetized patients.     

Insular carcinoma of the thyroid with jugular vein invasion

BACKGROUND: Gross angioinvasion with intraluminal tumor thrombus is rarely seen in thyroid cancer, with few cases reported in the literature. METHODS: We report an insular carcinoma of the thyroid displaying this aggressive local invasion and angioinvasion of the internal jugular chain. Complete surgical removal of the intraluminal disease, regional metastasis, and primary tumor was carried out. RESULTS: Adjuvant external beam radiation therapy and iodine-131 were administered, and the patient died with pulmonary metastases 30 months after surgery. No locoregional recurrence was noted at last follow-up. CONCLUSIONS: Treatment of insular carcinoma of the thyroid with invasion of the internal jugular vein is amenable to surgical resection. Postoperative radioactive iodine and external beam radiotherapy can achieve locoregional disease control and prolonged survival.     

Saphenous vein rupture pressure, rupture stress, and carotid endarterectomy vein patch reconstruction

Early postoperative patch rupture is a catastrophic complication of carotid endarterectomy reconstruction with greater saphenous vein. Mechanical determinants of saphenous vein rupture were identified by structural measurements and the results applied to carotid endarterectomy patch geometry. Diameter and rupture pressure was measured in fresh saphenous vein segments from the ankle, knee, or thigh in 157 patients undergoing bypass operations. Circumferential hoop rupture stress was calculated and the results were applied to 157 carotid endarterectomy reconstructions. All vein ruptures were in the cylindric axis. The mean vein diameter was 4.58 mm. The mean vein rupture pressure was 2873 mm Hg (3.78 atm). Vein diameter was larger in the thigh than in the ankle or knee (p less than 0.01), but there was no significant difference in rupture pressure between veins from the three locations. Women had a smaller vein diameter than had men at all locations (p less than 0.01). There was a positive linear correlation between vein diameter and rupture pressure. The mean maximum diameter of curvature of 157 carotid endarterectomy reconstructions with a vein patch was 13.3 mm. Multiple random applications of the 157 veins to 157 carotid diameters predicted a mean patch rupture pressure of 1087 mm Hg (1.43 atm), 1163 mm Hg (1.53 atm) for men, and 866 mm Hg (1.14 atm) for women. Predicted vein patch rupture pressures less than 300 mm Hg were found in 5.7% of cases (8.8% women and 1.2% men). Only 0.6% of patients (1.8% women and 0% men) had a predicted rupture pressure less than 200 mm Hg. No veins with a diameter greater than or equal to 4.0 mm had a predicted patch rupture pressure less than 300 mm Hg. These results suggest that small-diameter saphenous veins have a higher risk of rupture when used as a carotid patch.     

Effects of trendelenburg position and positive intrathoracic pressure on internal jugular vein cross-sectional area in anesthetized children

STUDY OBJECTIVE: To compare the cross-sectional area (in cm(2)) of the left internal jugular vein (LIJV) and right internal jugular vein (RIJV) in anesthetized children, and measure the response to the Trendelenburg tilt position (TBRG) and a positive inspiratory pressure hold. DESIGN: Prospective, nonrandomized study. SETTING: University medical center. PATIENTS: 45 ASA physical status I and II children, ages 6 months to 8 years, undergoing general anesthesia and mechanical ventilation.Interventions: The cross-sectional area of both internal jugular veins was measured with a 5-MHz, two-dimensional surface transducer, at the level of the cricoid cartilage. Three measurements were obtained: 1) with the patient supine, 2) during a 10-second breath-hold with a positive inspiratory pressure (PIP) of 20 cm H(2)O, and 3) with the patient at 20 degrees TBRG. Data were analyzed with two-way analysis of variance (ANOVA) and Student-Newman-Keuls test, with a p < 0.05 considered significant. MEASUREMENTS AND MAIN RESULTS: In supine patients, the cross-sectional area of the RIJV was larger than the LIJV in 31 patients (69%), and equal or smaller in 14 patients (31%) (0.80 +/- 0.38 vs. 0.59 +/- 0.22; p = 0.002). A PIP hold, but not TBRG, significantly dilated the RIJV (0.8 +/- 0.38 at baseline vs. 0.93 +/- 0.42 with TBRG; p = not significant vs. 1.1 +/- 0.46 with PIP; p < 0.05), whereas neither maneuver was effective with the LIJV. CONCLUSION: The cross-sectional area of the RIJV is often greater than the LIJV; the TBRG was not effective to increase the cross-sectional area of the internal jugular veins, and only a PIP hold increased significantly the cross-sectional area of the RIJV. In this study, the LIJV appeared of smaller size and less compliant compared with the RIJV.