[Clinical role of evaluating vascular paralysis in septic shock patients].

OBJECTIVE: To explore the effects of vascular paralysis upon prognosis and tissue perfusion in septic shock patients. METHODS: A total of 73 septic shock patients consecutively admitted into our department from January 2010 to July 2011 were retrospectively studied. Their hemodynamic data, arterial lactate concentration and APACHEII (acute physiology & chronic health evaluation II) score at the beginning of cardiac output monitoring (0h), as well as the outcome of Day 28 post-diagnosis were recorded. Stroke volume index (SVI) and cardiac index (CI) were obtained through transpulmonary thermodilution technique by pulse induced continuous cardiac output (PiCCO) system. RESULTS: (1) APACHEII score at 0h was higher in non-survivors than those in survivors ((14.6 ± 5.6) vs (20.4 ± 4.8), P < 0.01). Stroke systemic vascular resistance index (SSVRI), pulse pressure/stroke volume index (PP/SVI), effective arterial elastance index (EaI), 24h lactate clearance rate (24rLac) , 72h lactate clearance rate (72rLac) and 7d lactate clearance rate (7rLac) in non-survivors were all lower than those in survivors (P < 0.05); (2) SVRI, SSVRI, PP/SVI and EaI were all correlated significantly with 24rLac, 72rLac and 7rLac [ (212.7 ± 52.6) vs (185.4 ± 50.5) , PP/SVI: (2.8 ± 0.7) vs (2.5 ± 0.6), EaI: (5.0 ± 1.2) vs (4.3 ± 1.1), 24/72/7 rLac: (18.4 ± 46.4) vs (21.5 ± 49.7), (19.9 ± 49.6) vs (-21.5 ± 46.3), (35.5 ± 45.8) vs (-59.5 ± 64.5), P < 0.00]. CONCLUSION: Vascular paralysis is correlated with prognosis and tissue perfusion in septic shock patients. And SSVRI, PP/SVI and EaI are more significant.

[Variations of left ventricular-arterial coupling in septic shock].

OBJECTIVE: To explore the variations of left ventricular-arterial coupling and elucidate its mechanisms in septic shock. METHODS: Septic shock rabbits were established by an intravenous injection of endotoxin. A total of 12 rabbits were divided randomly into sham operation group (S, n = 6) and endotoxin injection group (E, n = 6). Ultrasonic echocardiography and hemodynamic monitoring were conducted at 0h (30-min post-operation), 2h (1-hour after endotoxin or saline injection) and 4h (3-hour after endotoxin or saline injection) and the relative hemodynamic indices were recorded. RESULTS: (1) In E group, end-systolic elastance (Ees) at 2h was lower than that at 0h (75.72 ± 5.16 vs 90.77 ± 7.17 mm Hg/ml) and Ees at 4h was lower than that at 2h (58.45 ± 3.63 vs 75.72 ± 5.16 mm Hg/ml, P < 0.05); (2) In E group, left ventricular diastolic volume (LVDV) at 2h and 4h were both lower than that at 0h (3.26 ± 0.21 vs 3.58 ± 0.25 ml, 3.27 ± 0.19 vs 3.58 ± 0.25 ml). And left ventricular end diastolic compliance (Ced) at 4h were lower than that at 0h and 2h (0.61 ± 0.05 vs 0.74 ± 0.07 ml/mm Hg, 0.61 ± 0.05 vs 0.75 ± 0.08 ml/mm Hg, P < 0.05); (3) In E group, Ea at 2h and 4h was lower than that at 0h (41.35 ± 2.87 vs 50.46 ± 3.22 mm Hg/ml, 40.13 ± 2.68 vs 50.46 ± 3.22 mm Hg/ml, P < 0.05); (4) In E group, Ea/Ees at 4h was higher than that at 0h and 4h (0.70 ± 0.07 vs 0.57 ± 0.06, 0.70 ± 0.07 vs 0.56 ± 0.05, P < 0.05). And Ea/Ees at 2h had no significant difference with that at 0h (0.56 ± 0.05 vs 0.57 ± 0.06, P < 0.05). CONCLUSION: During compensatory stage of septic shock, left ventricular-arterial coupling shows no significant variation. However, during decompensatory stage of septic shock, there is significant left ventricular-arterial decoupling. The main reason for decoupling lies in that the decrease of left myocardial contractility is more significant than that of left ventricular afterload. And ventricular diastolic dysfunction may also participate.

[Effects of early goal-directed diuresis therapy on the outcomes of critical ill patients].

OBJECTIVE: To evaluate the effects of early goal-directed diuresis therapy on the outcomes of critical ill patients. METHODS: A total of 56 critical patients enrolled received an injection of furosemide 5-40 mg under a precondition of stable hemodynamics. They were divided into two groups:standard group [Central venous pressure (CVP) decreased below 8 mm Hg] (n = 30) and control group (if not) (n = 26) depending on the goal of CVP.And the differences of survival rate, intensive care unit (ICU) days and ventilation days after diuresis therapy were compared between two groups. RESULTS: The survival rate of standard group was significantly higher than that of control group (96.7% vs 84.6%, P < 0.05) while the ICU days (4.4 ± 3.6 days) and ventilation days (1.2 ± 1.1 days) after diuresis therapy of standard group were significantly shorter than that of control group (12.5 ± 11.7 and 9.8 ± 9.6 days, P < 0.05). CONCLUSION: Early goal-directed diuresis therapy can improve the prognosis of critical ill patients.

[Value of dynamic arterial elastance in the predication of arterial pressure response to volume loading in shock patients].

OBJECTIVE: To explore the value of dynamic arterial elastance (Eadyn) in the predication of arterial pressure response to volume loading in shock patients. METHODS: A total of 32 patients with pulse indicator continuous cardiac output (PICCO) monitoring at our intensive care unit from January 2011 to December 2012 were retrospectively studied. The decision of fluid replacement was based upon the presence of shock (mean arterial pressure (MAP) ≤ 65 mm Hg, systolic arterial pressure <90 mm Hg or a decrease of 40 mm Hg from baseline) and preserved volume responsiveness condition with a stroke volume variation (SVV) value ≥ 10%. According to the MAP increase after volume loading, they were classified into MAP responders (≥ 15%) and MAP nonresponders (<15%) respectively. The goal was to investigate the influencing factors of the changes of MAP after volume loading and predict the arterial pressure response to volume loading. RESULTS: Significantly different between MAP responders and MAP nonresponders, baseline Eadyn was an effective predictor of MAP increase after volume loading. The area under the ROC curve was 0.95 for the prediction of volume loading on MAP for Eadyn at baseline (P < 0.01). A baseline Eadyn value >0.85 predicted a MAP increase after volume administration with a sensitivity of 89.5% and a specificity of 92.3%. CONCLUSION: Baseline Eadyn may predict accurately arterial pressure response in MAP to volume loading in shock patients.

Early versus late percutaneous dilational tracheostomy in critically ill patients anticipated requiring prolonged mechanical ventilation.

BACKGROUND: Tracheostomy should be considered to replace endotracheal intubation in patients requiring prolonged mechanical ventilation (MV). However, the optimal timing for tracheostomy is still a topic of debate. The present study aimed to investigate whether early percutaneous dilational tracheostomy (PDT) can reduce duration of MV, and to further verify whether early PDT can reduce sedative use, shorten intensive care unit (ICU) stay, decrease the incidence of ventilator associated pneumonia (VAP), and increase successful weaning and ICU discharge rate. METHODS: A prospective, randomized controlled trial was carried out in a surgical ICU from July 2008 to June 2011 in adult patients anticipated requiring prolonged MV via endotracheal intubation. Patients meeting the inclusion criteria were randomly assigned to the early PDT group or the late PDT group on day 3 of MV. The patients in the early PDT group were tracheostomized with PDT on day 3 of MV. The patients in the late PDT group were tracheostomized with PDT on day 15 of MV if they still needed MV. The primary endpoint was ventilator-free days at day 28 after randomization. The secondary endpoints were sedation-free days, ICU-free days, successful weaning and ICU discharge rate, and incidence of VAP at day 28 after randomization. The cumulative 60-day incidence of death after randomization was also analyzed. RESULTS: Total 119 patients were randomized to either the early PDT group (n = 58) or the late PDT group (n = 61). The ventilator-free days was significantly increased in the early PDT group than in the late PDT group ((9.57 ± 5.64) vs. (7.38 ± 6.17) days, P < 0.05). The sedation-free days and ICU-free days were also significantly increased in the early PDT group than in the late PDT group (20.84 ± 2.35 vs. 17.05 ± 2.30 days, P < 0.05; and 8.0 (interquartile range (IQR): 5.0 - 12.0) vs. 3.0 (IQR: 0 - 12.0) days, P < 0.001 respectively). The successful weaning and ICU discharge rate was significantly higher in early PDT group than in late PDT group (74.1% vs. 55.7%, P < 0.05; and 67.2% vs. 47.5%, P < 0.05 respectively). VAP was observed in 17 patients (29.3%) in early PDT group and in 30 patients (49.2%) in late PDT group (P < 0.05). There was no significant difference between the two groups in the cumulative 60-day incidence of death after randomization (P = 0.949). CONCLUSIONS: The early PDT resulted in more ventilator-free, sedation-free, and ICU-free days, higher successful weaning and ICU discharge rate, and lower incidence of VAP, but did not change the cumulative 60-day incidence of death in the patients' anticipated requiring prolonged mechanical ventilation.

[Left ventricular-arterial coupling in the resuscitation of refractory septic shock].

OBJECTIVE: To explore the role of left ventricular-arterial coupling in the resuscitation of refractory septic shock. METHODS: A total of 58 patients with refractory septic shock admitted from January 2010 to July 2011 were retrospectively studied. Hemodynamic data, arterial lactate concentration and APACHEII (acute physiology & chronic health evaluation II) score at the beginning of and 24 hours after cardiac output monitoring, as well as the outcome of Day 28 post-diagnosis were recorded. Stroke volume index (SVI), cardiac index (CI) and global end diastolic volume index (GEDVI) were obtained through transpulmonary thermodilution technique by a pulse induced continuous cardiac output (PiCCO) system. Left ventricular end systolic volume index (LVESVI) was approximated to (GEDVI/4-SVI) while effective arterial elastance index/ventricular end systolic elastance index (EaI/EesI) was approximated to LVESVI/SVI. RESULTS: (1) APACHEII score at the 24th hour, 24 hs lactate clearance rate and 24 hs Ea/Ees variation (ΔEa/Ees) were higher in non-survivors than those in survivors; (2) binary Logistic regression analysis showed that ΔEa/Ees and APACHEII score at the 24th hour were the independent risk factors of mortality for refractory septic shock. And the OR value of ΔEa/Ees was higher than that of APACHEII score (2.04 vs 1.63). Their areas of ROC curve were 0.705 (95%CI 0.569 - 0.841, P = 0.007) and 0.939 (95%CI 0.878 - 1.000, P = 0.000) respectively; (3) all hemodynamic parameters at the beginning had no difference between ΔEa/Ees > 0 and ΔEa/Ees ≤ 0 groups. CI, SVI, EGDT (early goal-directed therapy) compliance rate at the 24th hour in the ΔEa/Ees > 0 group were lower than those in the ΔEa/Ees ≤ 0 group. The effective arterial elastance index (EaI) at the 24th hour and the mortality rate of Day 28 in the ΔEa/Ees > 0 group were higher than those in the ΔEa/Ees ≤ 0 group; (4) during the 24 hs treatment, ΔEa/Ees was correlated negatively with the variations of CI, SVI, EesI and lactate clearance rate and positively with the variations of heart rate, GEDVI, systolic vascular resistance index and EaI. CONCLUSION: ΔEa/Ees may be used as an excellent marker of predicting the outcome of refractory septic shock. Lowing Ea/Ees in resuscitation has beneficial effects on EGDT compliance, lactate clearance and outcome.

[Value of power Doppler ultrasound to evaluate acute kidney injury].

OBJECTIVE: To explore the value of power Doppler ultrasound (PDU) in the evaluation of acute kidney injury(AKI). METHODS: Renal blood flow of 40 AKI cases was monitored by power Doppler ultrasound and 4-level semiquantitative PDU score method employed. All cases were divided into 3 groups by PDU score. AKI stage and duration were compared. And the co-variables of death and (continuous renal replacement therapy) CRRT days (> 3) were also analyzed by Logistic regression analysis. RESULTS: A total of 40 AKI case were recruited. The 3-score group (n = 13)has lower mortality in intensive care unit and at 28 days than the 2-score group (n = 15) and the 1-score group (n = 12). The number of stage-3 AKI in the 3-score group was less than that in the 2-score and 1-score groups (n = 1, 4, 9 correspondingly, χ(2) = 16.103, degree of freedom = 4, P = 0.003). The number of persistent AKI in the 3-score group was less than that in the 2-score and 1-score groups (n = 3, 9, 10 correspondingly, P < 0.05). Age, APACHEII score and PDU score (< 3) were closely correlated with death while age, APACHEII score, level of serum creatinine and PDU score (< 3) with CRRT days (> 3) (P < 0.05). CONCLUSION: PDU may be used to monitor renal hemodynamics in AKI patients and its score helps clinicians to evaluate the severity and prognosis of AKI.

[Effects of central venous pressure on acute kidney injury in septic shock].

OBJECTIVE: To investigate the effects of central venous pressure on acute kidney injury (AKI) in septic shock. METHODS: A total of 86 septic shock patients with PiCCO (pulse indicator continuous cardiac output) monitoring admitted at our department from January 2009 to January 2011 were retrospectively studied. They were divided into 2 groups based on central venous pressure (CVP) at 24 hs after PiCCO monitoring. There were 41 cases in low CVP group (CVP ≤ 10 mm Hg and 45 cases in high CVP group (CVP > 10 mm Hg). Their hemodynamic data, lactate concentration, ScvO2 (central venous oxygen saturation), APACHEII (acute physiology & chronic health evaluation II) score and serum creatinine were obtained at the beginning and 24 hours after PiCCO monitoring. The incidence and mortality of AKI, the outcome of these patients in ICU and at Day 28 post-diagnosis were recorded. RESULTS: (1) The incidences of AKI were 51.2% (21/41) and 75.6% (34/45) in low and high CVP groups respectively; (2) Nine cases (22.0%) died in ICU in low CVP group and 20 cases (44.4%) in high CVP group. And 12 cases (29.3%) died within 28 days in low CVP group while 21 cases (46.7%) in high CVP group. CONCLUSION: A high CVP may increase the incidence and morbidity of AKI in septic shock. And an excessively high CVP should be prevented.

[Stroke volume variation in the evaluation of fluid responsiveness in refractory septic shock].

OBJECTIVE: To evaluate fluid responsiveness by stroke volume variation(SVV) in mechanically ventilated patients with refractory septic shock. METHODS: Forty-two refractory septic shock patients were enrolled in the study. According to the responsiveness of fluid loading, the patients were divided into responsive group and non-responsive group. The SVV values of two groups were retrospectively analyzed. The receiver operating characteristic curve was drafted to determine the cut-off value of SVV for predicting fluid responsiveness. RESULTS: Among the 42 refractory septic shock patients, 24 were found responsive to fluid loading, 18 were not; before the fluid loading, central venous pressure, heart rate, mean arterial pressure and global end-diastolic volume index in the both groups showed no significant differences whereas the SVV in the responsive group was much higher than that in the nonresponsive group (P=0.006). Using SVV≥12% as the threshold to predict fluid responsiveness, the sensitivity was 77%, specificity was 85%. CONCLUSION: SVV can accurately predict fluid responsiveness in refractory septic shock patients.

[Stress gastrointestinal bleeding in critically ill patients and its effect on the prognosis].

OBJECTIVE: To investigate stress gastrointestinal bleeding in critically ill patients and its effect on the prognosis. METHODS: Clinical data of 1148 critically ill patients consecutively admitted to Intensive Care Unit of East Campuses of Peking Union Medical College Hospital during 2008 were analyzed retrospectively. The main contents of investigation included morbility and mortality of stress gastrointestinal bleeding in critically ill patients and its relationship with multiple organ dysfunction. RESULTS: Among the 1148 critically ill patients, organ dysfunction occurred in 254 cases, including 57 cases with shock, 124 with respiratory dysfunction, 46 with acute renal dysfunction, 192 with coagulation dysfunction and 40 with stress gastrointestinal bleeding. The patients with stress gastrointestinal bleeding took up 15.7% among organ dysfunction patients and 3.5% among critically ill patients. 97.5% stress gastrointestinal bleeding accompanied with other organ dysfunction. The mortality of stress gastrointestinal bleeding was 40.0%, which was higher than that of shock (28.1%), respiratory dysfunction (22.6%), renal dysfunction (30.4%) and coagulation dysfunction (13.5%) (all P<0.05). Binary Logistic regression analysis found that stress gastrointestinal bleeding was an independent risk factor associated with mortality (P<0.05). CONCLUSION: The patients with stress gastrointestinal bleeding usually have a poor prognosis.

Predictive value of RIFLE classification on prognosis of critically ill patients with acute kidney injury treated with continuous renal replacement therapy.

BACKGROUND: The optimal timing to start continuous renal replacement therapy (CRRT) for acute kidney injury (AKI) patients has not been accurately established. The recently proposed risk, injury, failure, loss, end-stage kidney disease (RIFLE) criteria for diagnosis and classification of AKI may provide a method for clinicians to decide the "optimal timing" for starting CRRT under uniform guidelines. The present study aimed: (1) to analyze the correlation between RIFLE stage at the start of CRRT and 90-day survival rate after CRRT start, (2) to further investigate the correlation of RIFLE stage with the malignant kidney outcome in the 90-day survivors, and (3) to determine the influence of the timing of CRRT defined by RIFLE classification on the 90-day survival and malignant kidney outcome in 90-day survivors. METHODS: A retrospective cohort analysis was performed on the data of 106 critically ill patients with AKI, treated with CRRT during a 6-year period in a university affiliated surgical intensive care unit (SICU). Information such as sex, age, RIFLE stage, sepsis, sepsis-related organ failure assessment (SOFA) score, number of organ failures before CRRT, CRRT time during SICU, survival, and kidney outcome conditions at 90 days after CRRT start was collected. According to their baseline severity of AKI at the start of CRRT, the patients were assigned to three groups according to the increasing severity of RIFLE stages: RIFLE-R (risk of renal dysfunction, R), RIFLE-I (injury to the kidney, I) and RIFLE-F (failure of kidney function, F) using RIFLE criteria. The malignant kidney outcome was classified as RIFLE-L (loss of kidney function, L) or RIFLE-E (end-stage kidney disease, E) using RIFLE criteria. The correlation between RIFLE stage and 90-day survival rate was analyzed among these three RIFLE-categorized groups. Additionally, the association between RIFLE stage and the malignant kidney outcome (RIFLE-L + RIFLF-E) in the 90-day survivors was analyzed. RESULTS: Fifty-three of the overall 106 patients survived to 90 days after the start of CRRT. There were 16, 22 and 68 patients in RIFLE-R, RIFLE-I and RIFLE-F groups respectively with corresponding 90-day survival rate of 75.0% (12/16), 63.6% (14/22) and 39.7% (27/68) (P < 0.01, compared among groups). The percentage of the malignant kidney outcome of 90-day survivors in the RIFLE-R, RIFLE-I, and RIFLE-F groups was 16.7% (2/12), 21.4% (3/14) and 55.6% (15/27), respectively (P for trend < 0.01). After adjustment for other baseline risk factors, the relative risk (RR) for the 90-day mortality significantly increased with baseline RIFLE stage. Patients in RIFLE-F had a higher RR of 1.96 (95% confidence interval (CI): 1.06 - 3.62) than patients in RIFLE-I (RR: 1.09, 95% CI: 0.55 - 2.15) compared with patients in RIFLE-R (P for trend < 0.01). Similarly, baseline RIFLE stage also significantly correlated with the odds ratio (OR) for the malignant kidney outcome in 90-day survivors (P for trend < 0.05). Ninety-day survivors in the RIFLE-F group had a borderline significantly highest OR of 6.88 (95% CI: 0.85 - 55.67). CONCLUSIONS: The RIFLE classification may be used to predict 90-day survival after starting CRRT and the malignant kidney outcome of 90-day survivors in the critically ill patients with AKI treated with CRRT. Starting CRRT prior to RIFLE-F stage may be the optimal timing. Prospective, multi-center, randomized controlled trials are needed to confirm its predictive value in these patients.