Hemoperfusion and blood purification strategies in patients with COVID-19: A systematic review

BACKGROUND

Coronavirus disease-19 (COVID-19) ranges from asymptomatic infection to severe cases requiring admission to the intensive care unit. Together with supportive therapies (ventilation in particular), the suppression of the pro-inflammatory state has been a hypothesized target. Pharmacological therapies with corticosteroids and interleukin-6 (IL-6) receptor antagonists have reduced mortality. The use of extracorporeal cytokine removal, also known as hemoperfusion (HP), could be a promising non-pharmacological approach to decrease the pro-inflammatory state in COVID-19.

METHODS

We conducted a systematic review of PubMed and EMBASE databases in order to summarize the evidence regarding HP therapy in COVID-19. We included original studies and case series enrolling at least five patients.

RESULTS

We included 11 articles and describe the characteristics of the populations studied from both clinical and biological perspectives. The methodological quality of the included studies was generally low. Only two studies had a control group, one of which included 101 patients in total. The remaining studies had a range between 10 and 50 patients included. There was large variability in the HP techniques implemented and in clinical and biological outcomes reported. Most studies described decreasing levels of IL-6 after HP treatment.

CONCLUSION

Our review does not support strong conclusions regarding the role of HP in COVID-19. Considering the very low level of clinical evidence detected, starting HP therapies in COVID-19 patients does not seem supported outside of clinical trials. Prospective randomized data are needed.

The role of neuromuscular blockade in patients with traumatic brain injury: a systematic review

Management of Traumatic Brain Injury (TBI) focuses on controlling intracranial pressure (ICP), while other treatments, such as the use of neuromuscular blocking agents (NMBAs), need scientific evidence. We conducted a systematic review to investigate the usefulness of NMBAs in the context of TBI and/or increased ICP. We searched MEDLINE and EMBASE databases up to January 31st 2014, including both clinical and experimental findings. We found a total of 34 articles, of which 22 were prospective clinical trials. No systematic review/meta-analyses were found. Seven studies evaluated NMBA boluses in preventing stimulation-related ICP surges: paralysis was effective during tracheal suctioning and physiotherapy but not during bronchoscopy. Fourteen small studies (8 to 25 patients) assessed the effect of NMBA boluses on ICP. Two studies showed an ICP increase by succinylcholine and one found a decrease in ICP after atracurium. No ICP changes were observed in the other studies. One prospective study confirmed that discontinuing paralysis increases energy expenditure. Two retrospective studies investigated mortality/morbidity: one found that early paralysis (continued for >12 h) was not beneficial and potentially associated with extra-cranial complications, while the second demonstrated a correlation between continuous infusion of NMBA and time spent with ICP > 20 mmHg. Eight animal studies were also retrieved. In most studies, NMBA bolus was beneficial in controlling ICP, especially when performing stimulating procedures. However, retrospective evidence found potential harm by continuous NMBA infusion. In the context of TBI patients, we discuss the potentially positive effects of paralysis with its negative ones. Well-conducted randomized controlled trials and/or large pharmaco-epidemiologic studies are warranted.

Assessment of the inferior vena cava collapsibility from subcostal and trans-hepatic imaging using both M-mode or artificial intelligence: a prospective study on healthy volunteers

PURPOSE

Assessment of the inferior vena cava (IVC) respiratory variation may be clinically useful for the estimation of fluid-responsiveness and venous congestion; however, imaging from subcostal (SC, sagittal) region is not always feasible. It is unclear if coronal trans-hepatic (TH) IVC imaging provides interchangeable results. The use of artificial intelligence (AI) with automated border tracking may be helpful as part of point-of-care ultrasound but it needs validation.

METHODS

Prospective observational study conducted in spontaneously breathing healthy volunteers with assessment of IVC collapsibility (IVCc) in SC and TH imaging, with measures taken in M-mode or with AI software. We calculated mean bias and limits of agreement (LoA), and the intra-class correlation (ICC) coefficient with their 95% confidence intervals.

RESULTS

Sixty volunteers were included; IVC was not visualized in five of them (n = 2, both SC and TH windows, 3.3%; n = 3 in TH approach, 5%). Compared with M-mode, AI showed good accuracy both for SC (IVCc: bias - 0.7%, LoA [- 24.9; 23.6]) and TH approach (IVCc: bias 3.7%, LoA [- 14.9; 22.3]). The ICC coefficients showed moderate reliability: 0.57 [0.36; 0.73] in SC, and 0.72 [0.55; 0.83] in TH. Comparing anatomical sites (SC vs TH), results produced by M-mode were not interchangeable (IVCc: bias 13.9%, LoA [- 18.1; 45.8]). When this evaluation was performed with AI, such difference became smaller: IVCc bias 7.7%, LoA [- 19.2; 34.6]. The correlation between SC and TH assessments was poor for M-mode (ICC = 0.08 [- 0.18; 0.34]) while moderate for AI (ICC = 0.69 [0.52; 0.81]).

CONCLUSIONS

The use of AI shows good accuracy when compared with the traditional M-mode IVC assessment, both for SC and TH imaging. Although AI reduces differences between sagittal and coronal IVC measurements, results from these sites are not interchangeable.

Central venous pressure monitoring via peripherally or centrally inserted central catheters: a systematic review and meta-analysis

INTRODUCTION

The central venous pressure (CVP) is the most commonly used static marker of preload for guiding fluid therapy in critically ill patients, though its usefulness remains controversial. Centrally inserted central catheters (CICCs) are the gold-standard devices for CVP monitoring but peripherally inserted central catheters (PICCs) may represent a valid alternative. We undertook a systematic review and meta-analysis with the aim to investigate whether the difference between PICC- and CICC-measured CVP is not significant.

METHODS

We searched for clinical studies published in PubMed and EMBASE databases from inception until December 21st 2016. We included studies providing data on paired and simultaneous CVP measurement from PICCs and CICCs. We conducted two analyses on the values of CVP, the first one according to the total number of CVP assessments, the second one considering the number of patients recruited.

RESULTS

Four studies matched the inclusion criteria, but only three of them provided data for the meta-analyses. Both analyses showed non-significant differences between PICC-measured and CICC-measured CVP: 1489 paired simultaneous CVP assessments (MD 0.16, 95%CI -0.14, 0.45, p = 0.30) on a total of 57 patients (MD 0.22, 95%CI -1.46, 1.91, p = 0.80). Both analyses showed no heterogeneity (I2 = 0%).

CONCLUSIONS

Available evidence supports that CVP monitoring with PICCs is accurate and reproduces similar values to those obtained from CICCs. The possibility to monitor CVP should not be used among clinical criteria for preferring a CICC over a PICC line.

Ten answers to key questions for fluid management in intensive care

This review focuses on fluid management of critically ill patients. The topic is addressed based on 10 single questions with simplified answers that provide clinicians with the basic information needed at the point of care in treating patients in the Intensive Care Unit. The review has didactic purposes and may serve both as an update on fluid management and as an introduction to the subject for novices in critical care. There is an urgent need to increase awareness regarding the potential risks associated with fluid overload. Clinicians should be mindful not only of the indications for administering fluid loads and of the type of fluids administered, but also of the importance to set safety limits. Lastly, it is important to implement proactive strategies seeking to establish negative fluid balance as soon as the clinical conditions are considered to be stable and the risk of deterioration is low.

The "CHEOPS" bundle for the management of Left Ventricular Diastolic Dysfunction in critically ill patients: an experts' opinion

The impact of left ventricular (LV) diastolic dysfunction (DD) on the outcome of patients with heart failure was established over three decades ago. Nevertheless, the relevance of LVDD for critically ill patients admitted to the intensive care unit has seen growing interest recently, and LVDD is associated with poor prognosis. Whilst an assessment of LV diastolic function is desirable in critically ill patients, treatment options for LVDD are very limited, and pharmacological possibilities to rapidly optimize diastolic function have not been found yet. Hence, a proactive approach might have a substantial role in improving the outcomes of these patients. Recalling historical Egyptian parallelism suggesting that Doppler echocardiography has been the "Rosetta stone" to decipher the study of LV diastolic function, we developed a potentially useful acronym for physicians at the bedside to optimize the management of critically ill patients with LVDD with the application of the bundle. We summarized the bundle under the acronym of the famous ancient Egyptian pharaoh CHEOPS: Chest Ultrasound, combining information from echocardiography and lung ultrasound; HEmodynamics assessment, with careful evaluation of heart rate and rhythm, as well as afterload and vasoactive drugs; OPtimization of mechanical ventilation and pulmonary circulation, considering the effects of positive end-expiratory pressure on both right and left heart function; Stabilization, with cautious fluid administration and prompt fluid removal whenever judged safe and valuable. Notably, the CHEOPS bundle represents experts' opinion and are not targeted at the initial resuscitation phase but rather for the optimization and subsequent period of critical illness.

Prevalence of burnout among intensive care physicians: a systematic review

OBJECTIVE

We performed a systematic review to summarize the knowledge regarding the prevalence of burnout among intensive care unit physicians.

METHODS

We conducted a systematic review of the MEDLINE and PubMed® databases (last update 04.02.2019) with the goal of summarizing the evidence on burnout among intensive care unit physicians. We included all studies reporting burnout in intensive care unit personnel according to the Maslach Burnout Inventory questionnaire and then screened studies for data on burnout among intensive care unit physician specifically.

RESULTS

We found 31 studies describing burnout in intensive care unit staff and including different healthcare profiles. Among these, 5 studies focused on physicians only, and 12 others investigated burnout in mixed intensive care unit personnel but provided separate data on physicians. The prevalence of burnout varied greatly across studies (range 18% - 49%), but several methodological discrepancies, among them cut-off criteria for defining burnout and variability in the Likert scale, precluded a meaningful pooled analysis.

CONCLUSION

The prevalence of burnout syndrome among intensive care unit physicians is relatively high, but significant methodological heterogeneities warrant caution being used in interpreting our results. The lower reported levels of burnout seem higher than those found in studies investigating mixed intensive care unit personnel. There is an urgent need for consensus recommending a consistent use of the Maslach Burnout Inventory test to screen burnout, in order to provide precise figures on burnout in intensive care unit physicians.

Liver function test abnormalities after traumatic brain injury: is hepato-biliary ultrasound a sensitive diagnostic tool?

BACKGROUND

This study was to evaluate the usefulness of hepato-biliary ultrasound (HBUS) for the investigation of isolated liver function tests (LFTs) abnormalities.

METHODS

We retrospectively reviewed HBUS reports in traumatic brain injury (TBI) patients admitted to our tertiary neuro-critical care unit (NCCU; January 2005-June 2011). We included patients receiving an HBUS for isolated LFTs derangement, excluding pre-existing hepato-biliary diseases or trauma. We assessed the temporal profile of alanine aminotransferase (ALT), bilirubin (Bil), and alkaline phosphatase (ALP).

RESULTS

Of 511 patients, 58 received an HBUS. Of these, 47 were investigated for isolated LFTs derangement; HBUS always failed to identify a cause for these abnormalities. The HBUS was performed on day 18 (range 6-51) with the following mean values: 246 IU litre(-1) [ALT, 95% confidence interval (CI) 183-308], 24 μmol litre(-1) (Bil, 95% CI 8-40), and 329 IU litre(-1) (ALP, 95% CI 267-390); only ALT (72, 95% CI 36-107) and ALP (73, 95% CI 65-81) were deranged from admission values (both P<0.01). At NCCU discharge, both ALT (160, 95% CI 118-202) and ALP (300, 95% CI 240-360) were higher than at admission (P<0.01). Compared with HBUS-day value, only ALT improved by NCCU discharge (P<0.05), while both were recovering by hospital discharge (ALT 83, 95% CI 59-107; ALP 216, 95% CI 181-251; P<0.01). At hospital discharge, ALP remained higher than at admission (P<0.01).

CONCLUSIONS

In TBI patients, HBUS did not appear sensitive in detecting causes for isolated LFT abnormalities. Both ALT and ALP worsened and gradually recovered. Their abnormalities did not prevent NCCU discharge. ALP recovered more slowly than ALT. TBI and its complications, critical illness, and pharmacological strategies may explain the LFTs derangement.

Self-citation policies and journal self-citation rate among Critical Care Medicine journals

BACKGROUND

Inappropriate authors' self-citation (A-SC) is a growing mal-practice possibly boosted by the raising importance given to author's metrics. Similarly, also excessive journals' self-citation (J-SC) practice may factitiously influence journal's metrics (impact factor, IF). Evaluating the appropriateness of each self-citation remains challenging.

MAIN BODY

We evaluated the presence of policies discouraging A-SC in Critical Care Medicine (CCM) journals with IF. We also calculated the J-SC rate of these journals. In order to evaluate if J-SC rates are influenced by the focus of interest of CCM journals, we separated them in three sub-categories ("multidisciplinary", "broad" or "topic-specific" CCM journals). We analyzed 35 CCM journals and only 5 (14.3%) discouraged excessive and inappropriate A-SC. The median IF was higher in CCM journals with A-SC policies [4.1 (3-12)] as compared to those without [2.5 (2-3.5); p = 0.02]. The J-SC rate was highly variable (0-35.4%), and not influenced by the presence of A-SC policies (p = 0.32). However, J-SC rate was different according to the focus of interest (p = 0.01): in particular, it was higher in "topic-specific" CCM journals [15.3 (8.8-23.3%)], followed by "broad" CCM [11.8 (4.8-17.9%)] and "multidisciplinary" journals [6.1 (3.6-9.1%)].

CONCLUSIONS

A limited number of CCM journals have policies for limiting A-SC, and these have higher IF. The J-SC rate among CCM journals is highly variable and higher in "topic-specific" interest CCM journals. Excluding self-referencing practice from scientific metrics calculation could be valuable to tackle this scientific malpractice.

Understanding left ventricular diastolic dysfunction in anesthesia and intensive care patients: "a glass with progressive shape change"

Left ventricular (LV) diastolic dysfunction is a commonly encountered condition and its impact on the in anesthesia and the intensive care population is often underestimated. The study of the diastole is known as "diastology" and comprises four phases: isovolumetric relaxation, early filling phase, diastasis, and late filling phase. Diastolic function needs at least the same attention as systolic function, since its alteration has been associated with worse prognosis. Notwithstanding, many physicians consider the assessment of diastolic function too much complex. In this context, the latest 2016 guideline have simplified the assessment of diastolic function. In this educational review, we approach diastolic dysfunction with didactic purposes. First, we use a metaphor to consider the LV as a glass that progressively changes its shape and height along the disease course, resembling variable end-diastolic pressures and volumes at different stages while progressing with diastolic dysfunction. We guide readers in the process of diagnosis and grading of LV diastolic dysfunction, with description of pathophysiological changes in LV relaxation and consequently in the pressure gradient between the left-sided heart chambers. In the second part, starting from physiology we move towards suggestions for the clinical management of anesthesia and intensive care patients with diastolic dysfunction under different scenarios (hypo- and hypervolemia, weaning, sepsis, tachycardia and arrhythmias, right ventricular dysfunction).

Clinical biomarkers in brain injury: a lesson from cardiac arrest

Cardiac arrest (CA) is the primary cause of death in industrialized countries. Successful resuscitation rate is estimated of about 40%, but a good neurological outcome remains difficult to achieve. The majority of resuscitated victims suffers of a pathophysiological entity termed as "post resuscitation disease". Today's efforts are mainly pointed to the chain of survival, often devoting less attention to post-resuscitation care. Resuscitated patients are often victims of nihilistic therapeutic approach, with clinicians failing to promptly institute strategies that mitigate the ischemia-reperfusion injury to vital organs. Only after 72 hours prognostication can be realistically attempted. Neurological evaluation relies on a combination of clinical, instrumental and laboratoristic parameters, since no one alone holds a specificity of 100%. Biochemical markers, such as neuron specific enolase and S-100b, may contribute to predict prognosis after CA. To the contrary, when used individually the necessary precision remains poorly characterized. Biochemical studies suffer from substantial methodological differences hampering attempts to summarize their findings. We review the information available on biochemical markers of brain damage for neurological prognostication after CA.

The Effects of On-Pump and Off-Pump Coronary Artery Bypass Surgery on Metabolic Profiles in the Early Postoperative Period

OBJECTIVE

Hyperlactatemia and base deficit (BD) are markers of adverse outcome after cardiac surgery, and their derangement can be influenced by the use of extracorporeal circulation. The authors hypothesized a better postoperative metabolic profile in off-pump coronary artery bypass grafting (OPCABG) compared with "on-pump" coronary artery bypass grafting (ONCABG).

DESIGN

This was a retrospective study, with consecutive data collected for 1 year from electronic medical records.

SETTING

Cardiothoracic intensive care unit at a tertiary university hospital.

PARTICIPANTS

The study comprised 339 patients who underwent elective coronary artery bypass grafting (ONCABG [n = 215], OPCABG [n = 124]).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The metabolic (arterial lactatemia, pH, and BD) and hemodynamic (inotropic/vasopressor support) parameters of OPCABG and ONCABG patients were compared at 7 predefined time points (intensive care admission and the 1st, 3rd, 6th, 12th, 18th, and 24th postoperative hours). For each output of interest, mixed-effects linear regression models were used (with time as random-effect to allow for clustering of repeated measures) and adjusted for a predetermined set of covariates. Arterial lactatemia and pH were comparable at all time points; BD was worse in the ONCABG group overall (p = 0.01) and at most time points (except at the 1st and 24th postoperative hours). For the whole period, inotropic support was more common in ONCABG patients (p<0.05), whereas vasopressor use was more frequent in the OPCABG group (p< 0.05).

CONCLUSIONS

Improved postoperative BD values were demonstrated in the OPCABG group, although pH and lactatemia were similar between groups. Inotropic support was less common in the OPCABG group at the expense of more frequent vasopressor support.

The Effect of Recruitment Maneuvers on Cerebrovascular Dynamics and Right Ventricular Function in Patients with Acute Brain Injury: A Single-Center Prospective Study

BACKGROUND

Optimization of ventilatory settings is challenging for patients in the neurointensive care unit, requiring a balance between precise gas exchange control, lung protection, and managing hemodynamic effects of positive pressure ventilation. Although recruitment maneuvers (RMs) may enhance oxygenation, they could also exert profound undesirable systemic impacts.

METHODS

The single-center, prospective study investigated the effects of RMs (up-titration of positive end-expiratory pressure) on multimodal neuromonitoring in patients with acute brain injury. Our primary focus was on intracranial pressure and secondarily on cerebral perfusion pressure (CPP) and other neurological parameters: cerebral autoregulation [pressure reactivity index (PRx)] and regional cerebral oxygenation (rSO2). We also assessed blood pressure and right ventricular (RV) function evaluated using tricuspid annular plane systolic excursion. Results are expressed as the difference (Δ) from baseline values obtained after completing the RMs.

RESULTS

Thirty-two patients were enrolled in the study. RMs resulted in increased intracranial pressure (Δ = 4.8 mm Hg) and reduced CPP (ΔCPP = -12.8 mm Hg) and mean arterial pressure (difference in mean arterial pressure = -5.2 mm Hg) (all p < 0.001). Cerebral autoregulation worsened (ΔPRx = 0.31 a.u.; p < 0.001). Despite higher systemic oxygenation (difference in partial pressure of O2 = 4 mm Hg; p = 0.001) and unchanged carbon dioxide levels, rSO2 marginally decreased (ΔrSO2 = -0.5%; p = 0.031), with a significant drop in arterial content and increase in the venous content. RV systolic function decreased (difference in tricuspid annular plane systolic excursion = -0.1 cm; p < 0.001) with a tendency toward increased RV basal diameter (p = 0.06). Grouping patients according to ΔCPP or ΔPRx revealed that those with poorer tolerance to RMs had higher CPP (p = 0.040) and a larger RV basal diameter (p = 0.034) at baseline.

CONCLUSIONS

In patients with acute brain injury, RMs appear to have adverse effects on cerebral hemodynamics. These findings might be partially explained by RM's impact on RV function. Further advanced echocardiography monitoring is required to prove this hypothesis.

Use of a Combined Laryngo-Bronchoscopy Approach in Difficult Airways Management: A Pilot Simulation Study

OBJECTIVE

There are several airway devices available for difficult tracheal intubation (DTI) management, but the failure rate remains high. The use of laryngoscopy to facilitate the fibreoptic-bronchoscope intubation (CLBI) has been increasingly reported in DTI situations, but it has not been formally studied yet.

METHODS

We designed a single-centre simulation study on DTI (neck rigidity and tongue oedema) comparing three techniques: direct laryngoscopy (DL), video-laryngoscopy (VLS) and CLBI. Eighteen anaesthesiologists naïve to VLS/CLBI approaches, participated in the study. The primary outcome was the intubation rate at the first attempt. Secondary outcomes were an overall time-to-intubate (TTI) and time-to-ventilate (TTV), success at the second and third attempt and ease of intubation as evaluated by a subjective 5-point Likert scale.

RESULTS

The CLBI technique had a higher success rate at the first attempt than DL (66% vs 22%, p=0.007), while VLS did not (44%, p=0.16). A trend towards higher success at the third attempt was found for both VLS and CLBI vs DL (p=0.07 and p=0.06, respectively). The VLS had a shorter overall TTV than DL (88±60 vs 121±59 sec, respectively, p=0.04) and a trend towards a shorter TTI (81±61 vs 116±64 sec, respectively, p=0.06). The CLBI approach showed a non-significantly lower TTI/TTV as compared to DL (p=0.10 and p=0.16, respectively). Anaesthesiologists judged that the intubation with VLS (3.7±1.0) and CLBI (3.8±1.0) was easier than with DL (1.7±0.8, both p<0.001).

CONCLUSION

In a simulated DTI scenario, CLBI had a higher success rate at the first attempt than DL, while VLS did not. By the third attempt, both rescue techniques had a trend towards a higher success rate than DL. The CLBI technique seems a promising alternative for the management of DTI.