الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 169 |  |  |
| | | from | 169 | | |
Abstract
Summary
In a patient with septic shock, a fluid challenge will cause an increase in stroke volume, according to the Frank-Starling curve. This increase in stroke volume has a salutary effect because it improves tissue perfusion. In contrast, higher hydrostatic pressures in the vascular system predispose the patient to edema, organic dysfunction, and increased risk of inhospital mortality
Relative hypovolemia has been described in the setting of septic shock. However, only 50 % of patients with hemodynamic instability are fluid responsive. Therefore, expeditious fluid resuscitation is advised, and clinicians must always weigh the benefits and risks of intravenous fluids.
Currently, both static and dynamic parameters are utilized for prediction of fluid responsiveness. Static parameters (e.g., central venous pressure and pulmonary artery occlusion pressure) are much less reliable than dynamic parameters, which are based on respirophasic variation in stroke volume (e.g., pulse pressure variation and changes in aortic blood flow)
Most common dynamic parameters are invasive (arterial and/or central venous cannulation is required) and expensive. Echocardiography is a well-established method for evaluating fluid responsiveness.
Nevertheless, measurement of left ventricular outflow tract velocities for the estimation of stroke volume is labor intense, requires specific training for adequate performance, and is not easily reproducible or obtainable. Thus, alternative methods, including brachial or carotid artery velocity, have been examined as surrogates for stroke volume in the septic shock patient population.
Moreover, most predictive indices for volume responsiveness are not validated in patients receiving lung protective ventilatory strategies. The aim of this study was to determine if respiratory variation in carotid Doppler peak velocity (ΔCDPV) can predict fluid responsiveness in patients with septic shock and lung protective mechanical ventilation.
The aim of this study was to study the diagnostic accuracy of respiratory variation of carotid peak systolic velocity in prediction of volume responsiveness in mechanically ventilated septic shock patients in comparison with other modalities of dynamic parameters.
Our study is a prospective interventional study that was carried out on 40 adult patients presented to critical care department, Beni-Suef University hospital with septic shock and were connected to mechanical ventilation.
Our study was held during the period from October 2017 to October 2018 and was approved by the ethical committee of faculty of medicine Beni-Suef University.
For volume expansion, we used 500ml normal isotonic saline 0.9% as fluid bolus. It was administered rapidly over 10 minutes. Two sets of measurements were performed: the first before VE and the second immediately after VE. Cardiac output (CO), stroke volume (SV), stroke volume index (SVI), IVC distensibility index were measured by trans-thoracic echocardiography and carotid peak systolic velocity index (CPSV) was measured by carotid Doppler. Respiratory variation of pulse pressure (PPV) and central venous pressure (CVP) were recorded.
Our study showed that the most important baseline patient parameters that could predict the fluid responsiveness of patient with septic shock are the CVS index followed by PPV% then IVC.
Regarding the baseline the CVS index, its sensitivity and specificity were 95% in prediction of fluid responsiveness at a cut off value 11.5.
Regarding the baseline PPV, its sensitivity was 95% and specificity was 90% in prediction of the fluid responsiveness at a cut off value 14.
Regarding the baseline IVC di, it can predict the response to fluid by sensitivity 85% and specificity90% at a cut off value 14.5.