The correlation between CVP-derived parameters and the prognosis of critically ill patients

Exploring the optimal range of central venous pressure in sepsis and septic shock patients: A retrospective study in 208 hospitals

BACKGROUND

The aim of this study was to investigate the optimal CVP range in sepsis and septic shock patients admitted to intensive care unit.

METHODS

We performed a retrospective study with adult sepsis patients with CVP records based on the eICU Collaborative Research Database. Multivariable logistic regression was performed to explore the associations between CVP level and hospital mortality. Non-linear correlations and optimal CVP range were explored using restricted cubic splines (RCS).

RESULTS

A total of 5302 sepsis patients were included in this study. Patients in 4-8 mmHg group owned the lowest odds ratio for raw hospital mortality (19.7%). The logistic regression analyses revealed that hospital death risk increased significantly when mean CVP level exceeds 12 mmHg compared to 4-8 mmHg level. U-shaped association of CVP with hospital mortality was revealed by RCS model in septic shock patients and the optimal range was 5.6-12 mmHg. While, there was a J-shaped trend for non-septic shock patients. For non-septic shock patients, patients had an increased risk of hospital death only if CVP exceeded 11 mmHg.

CONCLUSIONS

We observed U-shaped association between mean CVP level and hospital mortality in septic shock patients and J-shaped association in non-septic shock patients. This may imply that patients with different severity of sepsis have different CVP requirements. We need to monitor and manage CVP according to the circulatory status of the sepsis patient.

Intraoperative central venous pressure during cardiopulmonary bypass is an alternative indicator for early prediction of acute kidney injury in adult cardiac surgery

BACKGROUND

The relationship between venous congestion in cardiopulmonary bypass (CPB) and acute kidney injury (AKI) in cardiac surgery has not utterly substantiated. This study aimed at investigate the relationship between CVP in CPB and the occurrence of AKI.

METHODS

We retrospectively reviewed 2048 consecutive patients with cardiovascular disease undergoing cardiac procedure with CPB from January 2018 to December 2022. We used the median CVP value obtained during CPB for our analysis and patients were grouped according to this parameter. The primary outcomes were AKI and renal replacement therapy(RRT). Multivariable logistic regression was used to explore the association between CVP and AKI.

RESULTS

A total of 2048 patients were enrolled in our study and divided into high CVP group (CVP ≥ 6.5 mmHg) and low CVP group (CVP < 6.5 mmHg) according to the median CVP value. Patients in high CVP group had the high AKI and RRT rate when compared to the low CVPgroup[(367/912,40.24%)vs.(408/1136,35.92%),P = 0.045;(16/912,1.75%vs.9/1136;0.79%), P = 0.049]. Multivariate logistic regression analysis displayed CVP played an indispensable part in development of renal failure in surgical.

CONCLUSIONS

Elevated CVP(≥ 6.5mmH2OmmHg) in CPB during cardiac operation is associated with an increased risk of AKI in cardiovascular surgery patients. Clinical attention should be paid to the potential role of CVP in predicting the occurrence of AKI.

Optimization of central venous pressure during the perioperative period is associated with improved prognosis of high-risk operation patients

Background

While central venous pressure (CVP) measurement is used to guide fluid management for high-risk surgical patients during the perioperative period, its relationship to patient prognosis is unknown.

Methods

This single-center, retrospective observational study enrolled patients undergoing high-risk surgery from February 1, 2014 to November 31, 2020, who were admitted to the surgical intensive care unit (ICU) directly after surgery. Patients were divided into the following three groups according to the first CVP measurement (CVP1) after admission to the ICU: low, CVP1 <8 mmHg; moderate, 8 mmHg≤ CVP1 ≤ 12 mmHg; and high, CVP1 >12 mmHg. Perioperative fluid balance, 28-day mortality, length of stay in the ICU, and hospitalization and surgical complications were compared across groups.

Results

Of the 775 high-risk surgical patients enrolled in the study, 228 were included in the analysis. Median (interquartile range) positive fluid balance during surgery was lowest in the low CVP1 group and highest in the high CVP1 group (low CVP1: 770 [410, 1205] mL; moderate CVP1: 1070 [685, 1500] mL; high CVP1: 1570 [1008, 2000] mL; all P <0.001). The volume of positive fluid balance during the perioperative period was correlated with CVP1 (r=0.336, P <0.001). The partial arterial pressure of oxygen(PaO₂)/fraction of inspired oxygen(FiO₂) ratio was significantly lower in the high CVP1 group than in the low and moderate CVP1 groups (low CVP1: 400.0 [299.5, 443.3] mmHg; moderate CVP1: 362.5 [330.0, 434.9] mmHg; high CVP1: 335.3 [254.0, 363.5] mmHg; all P <0.001). The incidence of postoperative acute kidney injury (AKI) was lowest in the moderate CVP1 group (low CVP1: 9.2%; moderate CVP1: 2.7%; high CVP1: 16.0%; P=0.007). The proportion of patients receiving renal replacement therapy was highest in the high CVP1 group (low CVP1: 1.5%; moderate CVP1: 0.9%; high CVP1: 10.0%; P=0.014). Logistic regression analysis showed that intraoperative hypotension and CVP1 >12 mmHg were risk factors for AKI within 72 h after surgery (adjusted odds ratio[aOR]=3.875, 95% confidence interval[CI]: 1.378-10.900, P=0.010 and aOR=1.147, 95%CI: 1.006-1.309, P=0.041).

Conclusions

CVP that is either too high or too low increases the incidence of postoperative AKI. Sequential fluid therapy based on CVP after patients are transferred to the ICU post-surgery does not reduce the risk of organ dysfunction caused by an excessive amount of intraoperative fluid. However, CVP can be used as a safety limit indicator for perioperative fluid management in high-risk surgical patients.

Association between central venous pressure measurement and outcomes in critically ill patients with severe coma

BACKGROUND

The use of central venous pressure (CVP) measurements among (intensive care unit) ICU patients with severe coma has been questioned. This study aimed to investigate the application value of CVP in this population.

METHODS

Data stored in the ICU Collaborative Research Database (eICU-CRD) and Medical Information Mart for Intensive Care III (MIMIC-III) database were reviewed. Critically ill patients with a Glasgow Coma Scale (GCS) score of 3-8 were included. The primary outcome was the in-hospital mortality rate. The statistical approaches used included multivariable Cox regression, propensity score matching (PSM), inverse probability treatment weighting (IPTW), stabilized IPTW, and restricted cubic splines (RCS) to ensure the robustness of our findings.

RESULTS

In total, 7386 patients were included in the study. Early CVP measurement was independently associated with in-hospital mortality [hazard ratio, 0.63; p < 0.001] in patients with severe-to-moderate coma. This result was robust in the PSM, sIPTW, and IPTW cohorts. For all patients with CVP measurements, the RCS curves showed that the risk of in-hospital mortality increased as the initial CVP time was delayed. In addition, early CVP measurement was significantly associated with lower ICU mortality, 28-day mortality, and 365-day mortality and a significantly higher number of ventilator-free days.

CONCLUSION

Early CVP measurement could improve clinical outcomes in critically ill patients with severe coma.

Hepatic vein Doppler in critically ill patients: a reflection of central venous pressure or right ventricular systolic function?

Background

To explore whether hepatic vein systolic filling fraction (SFF) is associated with central venous pressure (CVP) and right ventricular (RV) systolic function in critically ill patients.

Methods

Adult patients admitted to ICU with echocardiographic examination were retrospectively enrolled. Echocardiographic parameters including hepatic vein systolic velocity (S) and diastolic phase velocity (D) and haemodynamic information at the time of echo examination were collected. RV systolic dysfunction was defined as tricuspid annular plane systolic excursion (TAPSE) < 16 mm. SFF was calculated as S/(S + D).

Results

Two hundred four patients were enrolled in this study among whom 40 patients had a CVP ≤5 mmHg, 110 patients had a CVP 6–9 mmHg and 54 patients had a CVP ≥10 mmHg. The three groups had similar S velocity, D velocity and SFF. No correlation between SFF and CVP was found (r = − 0.046, p = 0.500), but correlation between SFF and TAPSE was noticed (r = 0.468, p < 0.001). The ROC analysis showed that the area under curve (AUC) of SFF for determining CVP ≥10 mmHg was 0.513 (95% CI: 0.420–0.606, p = 0.775), but the AUC of SFF for determining RV systolic dysfunction was 0.759 (95% CI: 0.686–0.833, p < 0.001).

Conclusion

Hepatic vein systolic filling fraction is associated with RV systolic function in critically ill patients and is not associated with CVP.

Acute Kidney Injury Predictors and Outcomes after Cardiac Surgery in Children with Congenital Heart Disease: An Observational Cohort Study

Acute Kidney Injury (AKI) commonly complicates cardiac surgery in children with congenital heart disease (CHD). In this study we assessed incidence, risk factors, and outcomes of postoperative AKI, while testing the hypothesis that, depending on the underlying diagnosis, there would be significant differences in AKI incidence among different diagnostic groups. We conducted an observational cohort study of children with CHD undergoing cardiac surgery in a single tertiary center between January 2019 and August 2021 (n = 362). Kidney Disease Improving Global Outcome (KDIGO) criteria were used to determine the incidence of postoperative AKI. Diagnosis was incorporated into multivariate models using an anatomic-based CHD classification system. Overall survival was estimated using Kaplan−Meier curves. Log-rank test and adjusted Cox proportional hazard modelling were used to test for differences in survival distributions and determine AKI effect on survival function, respectively. AKI occurred in 70 (19.3%), with 21.4% in-hospital mortality for AKI group. Younger age, lower weight, longer cardiopulmonary bypass time, preoperative mechanical ventilation and diagnostic category were associated with postoperative AKI. Resolution rate was 92.7% prior to hospital discharge for survivors. AKI was associated with longer duration of mechanical ventilation, ICU and hospital length of stay. AKI patients had significantly higher probability of all-cause mortality postoperatively when compared to the non-AKI group (log-rank test, p < 0.001). Adjusted hazard ratio for AKI versus non-AKI group was 11.08 (95% CI 2.45−50.01; p = 0.002). Diagnostic category was associated with cardiac surgery-related AKI in children with CHD, a finding supporting the development of lesion specific models for risk stratification. Postoperative AKI had detrimental impact on clinical outcomes and was associated with decreased survival to hospital discharge.

Association Between the Central Venous Pressure and All-Cause Mortality in Critically Ill Patients with Acute Kidney Injury

Purpose

Elevated central venous pressure (CVP) plays an important role in the occurrence of acute kidney injury (AKI) and it is also independently associated with the prognosis of critically ill patients. However, the effect of CVP on critically ill AKI patients remains unclear. In this study, we analyzed the relationship between CVP and all-cause mortality of critically ill patients with AKI.

Patients and Methods

The clinical data of patients in intensive care unit (ICU) were retrieved from the Medical Information Mart for Intensive Care III (MIMIC-III) database and retrospectively analyzed. The all-cause mortality for up to 90 days was the main observed outcome. We used the minimum CVP value obtained during the first 72 hours after ICU admission for our analysis and patients were grouped according to this parameter. Patients were also analyzed after being further divided according to stages 1, 2 and 3 of AKI. Multiple Cox regression and Kaplan–Meier analyses were used to explore the association between CVP measurements and death of ICU patients with AKI.

Results

A total of 1986 ICU patients with AKI were studied. A total of 527 (26.5%) patients died by day 90. The high CVP group (patients with ≥10 mmHg) had the lowest 90-day survival rate (P =0.001 by log rank test) when according to Kaplan–Meier analysis. By using Cox regression analysis, high CVP was found to be linked to an increase in mortality (CVP ≥10 mmHg versus ≤5 mmHg, HR, 1.336, 95% CI, 1.064 to 1.677, P trend=0.014). Furthermore, when using in a multivariate Cox regression analysis with CVP as a continuous variable, the higher CVP levels were still an independent risk factor for 90-day all-cause mortality (per 1 mmHg increase, HR, 1.031, 95% CI, 1.013–1.049, P=0.001). In subgroup analysis, a similar trend was observed in patients with AKI stages 2 and 3.

Conclusion

The minimum CVP level during the first 72h after ICU admission was positively associated with mortality in critically ill patients with AKI and this more marked in cases with severe AKI.

Using the venous angle as a pressure reservoir to retrogradely fill the subclavian lymphatic trunk with contrast agent for lymphatic mapping

BACKGROUND

Visualizing the lymphatic system and recording the spatial relations between the subclavian lymphatic trunk (SLT) and the surrounding anatomical structures will improve radiotherapy treatment planning for breast cancer patients with lymphatic involvement. An experimental approach to retrogradely fill the SLT with contrast agent was explored.

METHODS

Six Thiel embalmed specimens were bilaterally dissected in the cervical and clavicular region to optimize the new experimental approach. A conservative dissection with minimum distortion of spatial relations between different anatomical structures was developed. A pressure reservoir was created inside the venous angle to allow retrograde filling of the SLT under the influence of time and pressure.

RESULTS

The new methodology proved feasible, showing successful pressure build-up inside the venous reservoir, resulting in filling of the proximal end of the subclavian lymphatic trunk. The pressures needed to significantly fill the subclavian lymphatic trunk proved to be higher than the pressures that the venous walls could withstand.

CONCLUSIONS

Thiel embalmed specimens proved useful for optimizing the experimental approach, but the embalming products could have negatively affected the vessel strength. The authors suggest that their method will be applied on fresh frozen specimens in future studies, to obtain SLT filling up to the axillary lymphatic plexus. Our findings also pointed out that there is still a lot to be learned about the anatomical variability of the SLT and its termination sites. The detailed description of our experimental approach offers valuable information for future lymphatic mapping studies.

Effects of Quality Control Targets (SpO2≠100%, PaCO2/<40 mmHg, Pmean/>10 cmH2O) on Outcomes in Patients in the ICU

Objectives: A series of quality control (QC) targets (SpO2≠100%, PaCO2≮40 mmHg, Pmean≯10 cmH2O) was put forward and widely used in a single intensive care unit (ICU) setting. The aim of this study was to assess whether these QC targets could improve the outcomes of critically ill patients.

Methods: The real-time clinical data of patients undergoing mechanical ventilation at ICU admission between May 2013 and May 2017 in the Department of Critical Care Medicine of Peking Union Medical College Hospital were collected and analyzed.

Results: A total of 7,670 patients [mean age, 58 years; 3,943 (51.5%) male] were divided into the before QC (n = 3,936) and after QC (n = 3,734) groups. QC targets (SpO2, PaCO2, and Pmean) and respiratory parameters (FiO2%, PaO2, PEEP, tidal volume, and respiratory rate) within 72 h of ICU admission, primary outcomes (ICU mortality, 28-, 60-, and 90-day mortality) and secondary outcomes (discharge against medical advice, ICU admission days, mechanical ventilation times, and central venous pressure) were measured and compared between the before and after QC groups. The 72 h average of the Pmean, FiO2%, PaO2, and VT were significantly lower and PaCO2 was higher in the after QC than in the before QC group (P < 0.05). A lower 90-day mortality rate, less discharge against medical advice, fewer ICU admission days, and reduced mechanical ventilation times were found in the after QC group compared with the before QC group (P < 0.05). Interestingly, CVP was significantly lower in the after QC group than in the before QC group (P < 0.05).

Conclusions: The QC targets (SpO2≠100%, PaCO2≮40 mmHg, Pmean≯10 cmH2O) contributed to avoiding high oxygen level hazards, protecting against lung injury, and improving circulatory function, which resulted in a better prognosis of critically ill patients.

Elevated central venous pressure is associated with increased mortality and acute kidney injury in critically ill patients: a meta-analysis

Background

The association of central venous pressure (CVP) and mortality and acute kidney injury (AKI) in critically ill adult patients remains unclear. We performed a meta-analysis to determine whether elevated CVP is associated with increased mortality and AKI in critically ill adult patients.

Methods

We searched PubMed and Embase through June 2019 to identify studies that investigated the association between CVP and mortality and/or AKI in critically ill adult patients admitted into the intensive care unit. We calculated the summary odds ratio (OR) and 95% CI using a random-effects model.

Results

Fifteen cohort studies with a broad spectrum of critically ill patients (mainly sepsis) were included. On a dichotomous scale, elevated CVP was associated with an increased risk of mortality (3 studies; 969 participants; OR, 1.65; 95% CI, 1.19–2.29) and AKI (2 studies; 689 participants; OR, 2.09; 95% CI, 1.39–3.14). On a continuous scale, higher CVP was associated with greater risk of mortality (5 studies; 7837 participants; OR, 1.10; 95% CI, 1.03–1.17) and AKI (6 studies; 5446 participants; OR, 1.14; 95% CI, 1.06–1.23). Furthermore, per 1 mmHg increase in CVP increased the odds of AKI by 6% (4 studies; 5150 participants; OR, 1.06; 95% CI, 1.01–1.12). Further analyses restricted to patients with sepsis showed consistent results.

Conclusions

Elevated CVP is associated with an increased risk of mortality and AKI in critically ill adult patients admitted into the intensive care unit.

Trial registration

PROSPERO, CRD42019126381

Pathophysiology of Volume Administration in Septic Shock and the Role of the Clinical Pharmacist

Objective: To review physiological rationale and evidence base surrounding fluid harm to prepare the clinical pharmacist for accountability regarding volume-related outcomes. Data Sources: A PubMed/MEDLINE search was conducted using the following terms: (fluid therapy) AND [(critical care) OR (sepsis)] from 1966 to August 2019 published in English. Study Selection and Data Extraction: A total of 3364 citations were reviewed with only relevant clinical data extracted. Data Synthesis: Although early fluid resuscitation may be a necessary component to decrease mortality in the majority of patients with septic shock admitted to the intensive care unit (ICU), the benefit of continued administration after the first 24 hours is uncertain. Paradoxically, a positive fluid balance secondary to intravenous fluid receipt has been associated with diverse and perpetuating detriment on a multitude of organ systems after the first 24 hours of ICU stay. Continued clinical harm has been demonstrated on patient outcomes such as rates of mortality and length of stay. Despite the growing body of evidence supporting the potential adverse aspects of positive fluid balance, fluid overload remains common during critical care admission. Conclusion: Physiological concerns to overly zealous fluid administration and subsequent volume overload are vast. Relevance to Patient Care and Clinical Practice: Optimization of fluid balance in critically ill patients with sepsis is primed for clinical pharmacy intervention. Critical care pharmacists have the potential to improve patient care by optimizing fluid pharmacotherapy while potentially reducing adverse events, days on mechanical ventilation, and length of ICU stay.

Untreated Relative Hypotension Measured as Perfusion Pressure Deficit During Management of Shock and New-Onset Acute Kidney Injury-A Literature Review

Maintaining an optimal blood pressure (BP) during shock is a fundamental tenet of critical care. Optimal BP targets may be different for different patients. In current practice, too often, uniform BP targets are pursued which may result in inadvertently accepting a degree of untreated relative hypotension, i.e., the deficit between patients' usual premorbid basal BP and the achieved BP, during vasopressor support. Relative hypotension is a common but an under-recognized and an under-treated sign among patients with potential shock state. From a physiological perspective, any relative reduction in the net perfusion pressure across an organ (e.g., renal) vasculature has a potential to overwhelm autoregulatory mechanisms, which are already under stress during shock. Such perfusion pressure deficit may consequently impact organs' ability to function or recover from an injured state. This review discusses such pathophysiologic mechanisms in detail with a particular focus on the risk of new-onset acute kidney injury (AKI). To review current literature, databases of Medline, Embase, and Google scholar were searched to retrieve articles that either adjusted BP targets based on patients' premorbid BP levels or considered relative hypotension as an exposure endpoint and assessed its association with clinical outcomes among acutely ill patients. There were no randomized controlled trials. Only seven studies could be identified and these were reviewed in detail. These studies indicated a significant association between the degree of relative hypotension that was inadvertently accepted in real-world practice and new-onset organ dysfunction or subsequent AKI. However, this is not a high-quality evidence. Therefore, well-designed randomized controlled trials are needed to evaluate whether adoption of individualized BP targets, which are initially guided by patient's premorbid basal BP and then tailored according to clinical response, is superior to conventional BP targets for vasopressor therapy, particularly among patients with vasodilatory shock states.