The Accuracy of the New Landmark Using Respiratory Jugular Venodilation and Direct Palpation in Right Internal Jugular Vein Access

<div><p>Background</p><p>Although ultrasonography is recommended in internal jugular vein (IJV) catheterization, the landmark-guided technique should still be considered. The central landmark using the two heads of the sternocleidomastoid muscle is widely used, but it is inaccurate for IJV access. As an alternative landmark, we investigated the accuracy of the new landmark determined by inspection of the respiratory jugular venodilation and direct IJV palpation in right IJV access by ultrasonography.</p><p>Methods and Findings</p><p>Thirty patients were enrolled. After induction of anesthesia, the central landmark was marked at the cricoid cartilage level (M1) and the alternative landmark determined by inspection of the respiratory jugular venodilation and direct palpation of IJV was also marked at the same level (M2). Using ultrasonography, the location of IJV was identified (M3) and the distance between M1 and M3 as well as between M2 and M3 were measured. The median (interquartile range) distance between the M2 and M3 was 3.5 (2.0–6.0) mm, compared to 17.5 (12.8–21.3) mm between M1 and M3. (<i>P</i><0.001) The dispersion of distances between M2 and M3 was significantly smaller than between M1 and M3. (<i>P</i><0.001) The visibility of respiratory jugular venodilation was associated with CVP more than 4 mmHg. Limitations of the present study are that the inter-observer variability was not investigated and that the visibility of the alternative landmark can be limited to right IJV in adults.</p><p>Conclusion</p><p>The alternative landmark may allow shorter distance for the right side IJV access than the central landmark and can offer advantages in right IJV catheterization when ultrasound device is unavailable.</p><p>Trial Registration</p><p>Clinical Research Informational Service <a href="http://cris.nih.go.kr" target="_blank">KCT0000812</a></p></div

CONSORT flow chart.

<p>CONSORT flow chart.</p

Anatomical location of the two landmarks in the patient.

<p>M1 is the central landmark (white arrow), determined by the apex of the triangle between the two heads of the sternocleidomastoid muscle. M2 is the alternative landmark (black arrow), determined by the inspection of respiratory jugular venodilation and direct internal jugular vein palpation.</p

ROC curve of the central venous pressure for the visible respiratory jugular venodilation.

<p>Area under the curve is given inside the ROC curve. ROC curve, receiver operator characteristic curve.</p

Comparison of distances between M1 and M2 from the ultrasound-identified IJV.

<p>Individual and median (interquartile range) distances between M1 and M2 from the ultrasound-identified IJV. For effective representation of the distance, the axes were inverted. The line in the middle box represents the median value and the lateral borders of the box represent interquartile ranges. Individual values are represented as dots (<i>yellow dots</i> in M1 and <i>green dots</i> in M2). M1, the central landmark; M2, the alternative landmark; IJV, internal jugular vein.</p

Variables in the ZEEP and PEEP groups during robot-assisted laparoscopic prostatectomy.

<p>Variables in the ZEEP and PEEP groups during robot-assisted laparoscopic prostatectomy.</p

Effect of Positive End-Expiratory Pressure on the Sonographic Optic Nerve Sheath Diameter as a Surrogate for Intracranial Pressure during Robot-Assisted Laparoscopic Prostatectomy: A Randomized Controlled Trial

<div><p>Background</p><p>Positive end-expiratory pressure (PEEP) can increase intracranial pressure. Pneumoperitoneum and the Trendelenburg position are associated with an increased intracranial pressure. We investigated whether PEEP ventilation could additionally influence the sonographic optic nerve sheath diameter as a surrogate for intracranial pressure during pneumoperitoneum combined with the Trendelenburg position in patients undergoing robot-assisted laparoscopic prostatectomy.</p><p>Methods</p><p>After anesthetic induction, 38 patients were randomly allocated to a low tidal volume ventilation (8 ml/kg) without PEEP group (zero end-expiratory pressure [ZEEP] group, n = 19) or low tidal volume ventilation with 8 cmH₂O PEEP group (PEEP group, n = 19). The sonographic optic nerve sheath diameter was measured prior to skin incision, 5 min and 30 min after pneumoperitoneum and the Trendelenburg position, and at the end of surgery. The study endpoint was the difference in the sonographic optic nerve sheath diameter 5 min after pneumoperitoneum and the Trendelenburg position between the ZEEP and PEEP groups.</p><p>Results</p><p>Optic nerve sheath diameters 5 min after pneumoperitoneum and the Trendelenburg position did not significantly differ between the groups [least square mean (95% confidence interval); 4.8 (4.6–4.9) mm vs 4.8 (4.7–5.0) mm, P = 0.618]. Optic nerve sheath diameters 30 min after pneumoperitoneum and the Trendelenburg position also did not differ between the groups [least square mean (95% confidence interval); 4.5 (4.3–4.6) mm vs 4.5 (4.4–4.6) mm, P = 0.733].</p><p>Conclusions</p><p>An 8 cmH₂O PEEP application under low tidal volume ventilation does not induce an increase in the optic nerve sheath diameter during pneumoperitoneum combined with the steep Trendelenburg position, suggesting that there might be no detrimental effects of PEEP on the intracranial pressure during robot-assisted laparoscopic prostatectomy.</p><p>Trial Registration</p><p>ClinicalTrial.gov <a href="https://clinicaltrials.gov/ct2/show/NCT02516566" target="_blank">NCT02516566</a></p></div

Sonographic optic nerve sheath diameter in the ZEEP and PEEP groups during robot-assisted laparoscopic prostatectomy.

<p>Sonographic optic nerve sheath diameter in the ZEEP and PEEP groups during robot-assisted laparoscopic prostatectomy.</p

Study flow diagram.

<p>Patients in the zero end-expiratory pressure (ZEEP) group received mechanical ventilation with a tidal volume 8 ml/kg of ideal body weight without positive end-expiratory pressure (PEEP), and those in PEEP group received mechanical ventilation with a tidal volume 8 ml/kg of ideal body weight with 8 cmH₂O PEEP.</p

Demographic data.

<p>Demographic data.</p