In the present work, we proposed that the use of ECHO to guide treatment of sepsis and septic shock will be associated with better outcome. Thus, we designed the present study to examine this hypothesis in the light of available gold standard of sepsis treatment (i.e. EGDT) at the time of the study. We prospectively evaluated a group of patients whose treatment was guided by ECHO and compared the results with a group of patients who received EGDT.
Our results regarding the mortality is comparable to those reported by Chertoff et al. [21] who reported a mortality rate of 29.69%. In addition, the reported incidence of mortality in the present work lies within reported range in literature; the short-term mortality is 20–30%, and up to 50% in patients with septic shock [1,22].
In contrary to Lanspa et al. [8] who reported insignificant difference between ECHO-guided resuscitation compared to EGDT in mortality, ICU stay or lactate clearance. This could be a result of late ECHO assessment after initial resuscitation as no difference in fluids administration between the two groups in contrary to our study results which showed a statistically significant difference between groups in the fluid resuscitation volume.
The present work revealed that the baseline MAP of both groups shows no significant difference. Then the MAP of the ECHO group became higher significantly than that of the EGDT group after 6 and 12 hours of the study. Thereafter, the MAP of both groups shows no significant difference at 24 hours from enrolment. This means that the ECHO group reached the target MAP earlier.
As well, Lin [23] and his colleagues observed improvement of blood pressure of the intervention group when they tested the effect of modified goal-directed protocol (targeting specific MAP, CVP and UOP without targeting ScvO2 on the clinical outcome of septic shock patients. However, the MAP of the intervention group stayed significantly higher throughout the study [23].
In the current work, there was no statistically significant difference between both groups as regards the HR at the start of the study, then the HR starting from 6 hours till 24 hours after the enrolment differed significantly between both groups.
The significant decrease in the HR in the ECHO group was shown as well when the HR measurement was compared to the baseline HR at enrolment in the study. This decrease in the HR in the ECHO group can be a preceding indicator of the improvement of the hemodynamics which also correlated with higher MAP in the ECHO group.
The fluid therapy in the EGDT group was according to the CVP (targeting CVP between 8–12 mm Hg). This CVP guidance made the fluid therapy relatively higher in the EGDT group. Most of recent studies that test the CVP in guiding fluid therapy criticize the CVP as a predictor of fluid responsiveness as it may be falsely high in volume-depleted patient hindering useful fluid resuscitation or it may be falsely low in volume overloaded patient exposing the patient to more overload or even pulmonary congestion and edema. However, it is still used by many clinicians in ICU.
In agreement with our results, a study by Feng et al. [24]. who reported that those who had trans-thoracic ECHO (TTE) had a higher maximum dose of norepinephrine, but surprisingly were weaned of vasopressors earlier compared to the no TTE group. Dobutamine was used more often in the group who received TTE, they concluded that performance of TTE is associated with a 28-day mortality benefit in a general population of septic, critically ill patients [24].
This is also in agreement with Kanji et al. [25] reported more utilization of Dobutamine in the limited ECHO group compared to the standard management.
In the present study we reported significantly lower number, in ECHO group versus EGDT group, of mechanically ventilation days, ICU stay, and hospital stay due to earlier weaning from vasopressors and Mechanical ventilation.
This is in disagreement with Lanspa et al. [26] who reported an insignificant difference between the echo group and non-echo group (median of 28 days versus 25 days; p = 0.51). Also, Feng et al. [24] reported no significant difference in ventilation-free days between ECHO group and non-ECHO groups.
Overall, results of the present work indicated that, ECHO as a sole monitoring and guiding tool was associated with better outcome than EGDT as evidenced from enhancement of vital data over time, decreased total fluid administration, significant decrease of 30 day and overall mortality. Critical care ultrasound may be considered the fifth pillar of clinical examination especially in critically ill patients. ECHO is widely used in critical care medicine [27,28].
Finally, it may be the first time to compare outcome between EGDT and use of echocardiographic findings to govern the progress of management in sepsis and septic shock. Results of the present work seems to be promising. However, further studies with larger sample size and in multi-centers are needed to generalize the routine use of ECHO in management of hemodynamic in severe sepsis and septic shock provides. Anyway, present work advocates routine uses of ECHO as a crucial, non-invasive bedside tool for the management of patients with severe sepsis and septic shock.
Another limitation of our study is the use of old definitions of sepsis, sever sepsis and septic shock and it’s preferred to depend on the new definitions for sepsis and septic shock provided by the International Consensus (Sepsis-3) in 2016 [29].
Further studies are needed to reveal the role of early diagnosis by new scores as Quick Sequential Organ Function Assessment (qSOFA) and qSOFA-65 [30] which helps in prediction and thereby early management.
Limitations in ECHO use still exist; low echogenicity at surface examination. Whenever there is strict requirement of continuous monitoring of cardiac output or pulmonary artery pressure, ECHO is not the right tool. Also, in centers where adequate training on the use of critical care ECHO does not exist, and repeated bedside assessment of hemodynamic variables are required, ECHO is of limited use as a single monitoring tool. Patients excluded from the study e.g. morbid obese and atrial fibrillation still represent challenges in echocardiographic assessments and follow up either due to inconsistency of cardiac output on LVOT VTI or limited window for examination respectively.