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Internal Jugular Vein Variability Predicts Fluid Responsiveness in Cardiac

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Internal Jugular Vein Variability Predicts Fluid Responsiveness in Cardiac Ma et al. Ann. Intensive Care (2018) 8:6 https://doi.org/10.1186/s13613-017-0347-5 RESEARCH Open Access Internal jugular vein variability predicts fuid responsiveness in cardiac surgical patients with mechanical ventilation Guo‑guang Ma†, Guang‑wei Hao†, Xiao‑mei Yang, Du‑ming Zhu, Lan Liu, Hua Liu, Guo‑wei Tu* and Zhe Luo* Abstract Background: To evaluate the efcacy of using internal jugular vein variability (IJVV) as an index of fuid responsive‑ ness in mechanically ventilated patients after cardiac surgery. Methods: Seventy patients were assessed after cardiac surgery. Hemodynamic data coupled with ultrasound evaluation of IJVV and inferior vena cava variability (IVCV) were collected and calculated at baseline, after a pas‑ sive leg raising (PLR) test and after a 500-ml fuid challenge. Patients were divided into volume responders (increase in stroke volume 15%) and non-responders (increase in stroke volume < 15%). We compared the diferences in measured variables≥ between responders and non-responders and tested the ability of the indices to predict fuid responsiveness. Results: Thirty-fve (50%) patients were fuid responders. Responders presented higher IJVV, IVCV and stroke vol‑ ume variation (SVV) compared with non-responders at baseline (P < 0.05). The relationship between IJVV and SVV was moderately correlated (r 0.51, P < 0.01). The areas under the receiver operating characteristic (ROC) curves for predicting fuid responsiveness= were 0.88 (CI 0.78–0.94) for IJVV compared with 0.83 (CI 0.72–0.91), 0.97 (CI 0.89–0.99), 0.91 (CI 0.82–0.97) for IVCV, SVV, and the increase in stroke volume in response to a PLR test, respectively. Conclusions: Ultrasound-derived IJVV is an accurate, easily acquired noninvasive parameter of fuid responsiveness in mechanically ventilated postoperative cardiac surgery patients, with a performance similar to that of IVCV. Keywords: Internal jugular veins, Inferior vena cava, Stroke volume variation, Fluid responsiveness, Cardiac surgery Background regarding fuid management in patients with a limited Fluid management is one of the most important treat- cardiac reserve. ments for stabilizing hemodynamics in patients after It is imperative to predict the patient’s fuid respon- cardiac surgery. Hypovolemia may lead to inadequate siveness before volume expansion [5]. Several param- organ perfusion, whereas fuid overload may lead to post- eters have been introduced in clinical practice to predict operative complications such as congestive heart failure fuid responsiveness and to guide therapy [2]. Based on or pulmonary edema [1–3]. In addition, patients who the infuence of cycling intra-thoracic pressure on arte- underwent cardiac surgery have a certain degree of myo- rial pulse pressure or stroke volume, dynamic indicators cardial stunning [4], and hence, caution should be taken such as arterial pulse pressure variation (PPV) or stroke volume variation (SVV) have been widely used as reliable predictors of fuid responsiveness [6–8]. However, these dynamic parameters have several limitations and can *Correspondence: tu.guowei@zs‑hospital.sh.cn; luo.zhe@zs‑hospital.sh.cn †Guo-guang Ma and Guang-wei Hao have contributed equally to this only be used under strict conditions. work Recently, noninvasive and point-of-care ultrasound Department of Critical Care Medicine, Zhongshan Hospital, Fudan seems to meet the criteria of an ideal bedside tool for University, No. 180 Fenglin Road, Shanghai 200032, Xuhui District, People’s Republic of China fuid status assessment. Several studies have confrmed © The Author(s) 2018. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Ma et al. Ann. Intensive Care (2018) 8:6 Page 2 of 9 that respiratory variations of the superior and inferior hypoperfusion (renal dysfunction or hyperlactatemia). vena cava diameters (collapsibility index [CI] and dis- Te exclusion criteria included age < 18 years; evidence tensibility index [DI]) accurately refect volume respon- of cardiac arrhythmia (e.g., atrial fbrillation); evidence siveness in mechanically ventilated patients [9, 10]. of jugular vein thrombosis; bilaterally inserted venous Unfortunately, measurements of the inferior vena cava catheters (jugular or subclavian vein); echocardiographic (IVC) and superior vena cava (SVC) may fail to predict examination that showed the existence of severe tricuspid fuid responsiveness following cardiac surgery due to or mitral regurgitation or right heart dysfunction (right methodological problems such as poor subcostal caval ventricular fractional area change < 40% examined by image quality caused by mediastinal air, surgical drains, TEE; tricuspid annular plane systolic excursion < 16 mm dressings, abdominal distension or morbid obesity [11– examined by TTE); a history of radiotherapy or surgery 13]; a more accurate measurement would require tran- of the neck region or back (making it impossible to put soesophageal echocardiography (TEE). It is well known the patient in a supine position with the head elevated to that pressure and volume changes within the intra-tho- 30°); a contraindication to the passive leg raising (PLR) racic systemic venous compartment can transmit to the test; and the inability to obtain interpretable ultrasound extrathoracic veins, for example, the intra-abdominal images due to a difcult acoustic window. IVC or extrathoracic internal jugular vein (IJV) [14–16]. All enrolled patients were sedated via propofol and Te IJV is, technically, much more easily accessible for morphine infusion, and with absence of inspiratory sonographic visualization than the IVC, and measure- eforts according to the ventilator waveform and moni- ment of the IJV does not require TEE. Internal jugular toring parameters. No muscular blocking agents were vein variability (IJVV) has been studied in several studies used in this study. All patients were ventilated in the [17–19], but its reliability has not been well confrmed in intermittent positive pressure ventilation (IPPV) mode patients after cardiac surgery. Te aim of this study was in the supine position with the head elevated to 30°. Te to evaluate the reliability of IJVV, as visualized by ultra- ventilatory parameters were adjusted to the following cri- sound, to predict fuid responsiveness in mechanically teria: tidal volume (Vt): 8 ml/kg predicted body weight ventilated patients after cardiac surgery. (PBW), Pplat < 30 cmH2O, positive end-expiratory pres- sure (PEEP): 5 cmH2O, respiratory rate: 12–16 breaths Methods per minute, PaCO2 ≤ 45 mmHg and oxygen saturation Tis study was approved by the Ethical Committee of (SaO2) > 96%. Te following baseline data were recorded Zhongshan Hospital afliated to Fudan University (No. for each patient: age (years), weight (kg), height (cm), B2016077), and informed consent was obtained from all diagnosis, type of cardiac surgery, acute physiology and study participants. Tis trial has been registered at clini- chronic health evaluation (APACHE) II score, Euro- caltrials.gov as NCT02852889. pean system for cardiac operative risk evaluation (Euro- SCORE), vasoactive drug infusion rates and preoperative Patient selection echocardiographic parameters [left ventricular ejection Patients who underwent cardiac surgery between August fraction (LVEF), presence of left ventricular hypertrophy, and December 2016 in the Cardiac Surgery Intensive right ventricular end-diastolic diameter, and tricuspid Care Unit (CSICU) of the Zhongshan Hospital of Fudan regurgitation grade]. University were screened for inclusion by research per- sonnel. All patients routinely underwent a TEE during Measurements the operation and a postoperative (after admission to We analyzed a series of measured hemodynamic vari- ICU and prior to study enrollment) comprehensive tran- ables from an indwelling radial arterial catheter and cen- sthoracic echocardiography (TTE). Te TEE was used to tral venous catheter in each patient. Tese data included monitor the hemodynamics and confrm the postopera- heart rate (HR) (beats/minute), mean arterial pressure tive efect of surgery. TTE was used to identify diferent (MAP) (mmHg), central venous pressure (CVP) (mmHg), causes of hypotension in postoperative period such as stroke volume (SV) (ml), PLR-induced increase in stroke obstructive shock, hypovolemia and reduced ventricu- volume (PLR-ΔSV) (ml), and stroke volume variation lar systolic function. Te patients were included when (SVV) using the FloTrac/Vigileo (Edwards Lifesciences, they presented with circulatory instability and required Irvine, CA, USA) continuous hemodynamic monitor- a rapid fuid challenge based on the clinical judgment ing system. Te pressure transducers were consistently of the attending physician. Te physician’s decision was adjusted to the level of the patient’s right atrium. principally based on the presence of clinical signs of acute Intensivists with a certifcation of ultrasound evalu- circulatory failure (low blood pressure or urine output, ation performed all of the ultrasound examinations. An tachycardia, or mottling) and/or clinical signs of organ associate critical care professor supervised the entire Ma et al. Ann. Intensive Care (2018) 8:6 Page 3 of 9 course of examinations. Te
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