Johan Groeneveld

Cardiac dysfunction after aneurysmal subarachnoid hemorrhage: Relationship with outcome

Objective: To assess whether cardiac abnormalities after aneurysmal subarachnoid hemorrhage (aSAH) are associated with delayed cerebral ischemia (DCI) and clinical outcome, independent from known clinical risk factors for these outcomes. Methods: In a prospective, multicenter cohort study, we performed echocardiography and ECG and measured biochemical markers for myocardial damage in patients with aSAH. Outcomes were DCI, death, and poor clinical outcome (death or dependency for activities of daily living) at 3 months. With multivariable Poisson regression analysis, we calculated risk ratios (RRs) with corresponding 95% confidence intervals. We used survival analysis to assess cumulative percentage of death in patients with and without echocardiographic wall motion abnormalities (WMAs). Results: We included 301 patients with a mean age of 57 years; 70% were women. A wall motion score index ≥1.2 had an adjusted RR of 1.2 (0.9–1.6) for DCI, 1.9 (1.1–3.3) for death, and 1.8 (1.1–3.0) for poor outcome. Midventricular WMAs had adjusted RRs of 1.1 (0.8–1.4) for DCI, 2.3 (1.4–3.8) for death, and 2.2 (1.4–3.5) for poor outcome. For apical WMAs, adjusted RRs were 1.3 (1.1–1.7) for DCI, 1.5 (0.8–2.7) for death, and 1.4 (0.8–2.5) for poor outcome. Elevated troponin T levels, ST-segment changes, and low voltage on the admission ECGs had a univariable association with death but were not independent predictors for outcome. Conclusion: WMAs are independent risk factors for clinical outcome after aSAH. This relation is partly explained by a higher risk of DCI. Further study should aim at treatment strategies for these aSAH-related cardiac abnormalities to improve clinical outcome.

Incidence and prognosis of dysnatraemia in critically ill patients: analysis of a large prevalence study

The objective of this study is to assess the impact of dysnatraemia on mortality among intensive care unit (ICU) patients in a large, international cohort.

ARDS of Early or Late Onset: Does It Make a Difference?

BACKGROUND Differences in outcomes have been demonstrated for critically ill patients with late-onset compared with early-onset renal failure and late-onset compared with early-onset shock, which could cause a lead-time bias in clinical trials assessing potential therapies for these conditions. We used data from a large, multicenter observational study to assess whether late-onset ARDS was similarly associated with worse outcomes compared with early-onset ARDS. METHODS Data were extracted from the Sepsis Occurrence in Acutely Ill Patients (SOAP) study, which involved 198 ICUs from 24 European countries. All adult patients admitted to a participating ICU between May 1, 2002 and May 15, 2002, were eligible, except those admitted for uncomplicated postoperative surveillance. Early/late onset acute lung injury (ALI)/ARDS was defined as ALI/ARDS occurring within/after 48 h of ICU admission. RESULTS Of the 3,147 patients included in the SOAP study, 393 (12.5%) had a diagnosis of ALI/ARDS; 254 had early-onset ALI/ARDS (64.6%), and 139 (35.5%) late-onset. Patients with early-onset ALI/ARDS had higher Simplified Acute Physiology II scores on admission and higher initial Sequential Organ Failure Assessment scores. Patients with late-onset ALI/ARDS had longer ICU and hospital lengths of stay than patients with early-onset ALI/ARDS. ICU and hospital mortality rates were, if anything, lower in late-onset ALI/ARDS than in early-onset ALI/ARDS, but these differences were not statistically significant. CONCLUSIONS There were no significant differences in mortality rates between early- and late-onset ARDS, but patients with late-onset ALI/ARDS had longer ICU and hospital lengths of stay.

Relative value of pressures and volumes in assessing fluid responsiveness after valvular and coronary artery surgery

BACKGROUND AND AIMS Cardiac function may differ after valvular (VS) and coronary artery (CAS) surgery and this may affect assessment of fluid responsiveness. The aim of the study was to compare VS and CAS in the value of cardiac filling pressures and volumes herein. METHODS There were eight consecutive patients after VS and eight after CAS, with femoral and pulmonary artery catheters in place. In each patient, five sequential fluid loading steps of 250 ml of colloid each were done. We measured central venous pressure (CVP), pulmonary artery occlusion pressure (PAOP) and, by transpulmonary thermodilution, cardiac index (CI) and global end-diastolic (GEDVI) and intrathoracic blood volume (ITBVI) indices. Fluid responsiveness was defined by a CI increase >5% or >10% per step. RESULTS Global ejection fraction was lower and PAOP was higher after VS than CAS. In responding steps after VS (n=9-14) PAOP and volumes increased, while CVP and volumes increased in responding steps (n=12-19) after CAS. Baseline PAOP was lower in responding steps after VS only. Hence, baseline PAOP as well as changes in PAOP and volumes were of predictive value after VS and changes in CVP and volumes after CAS, in receiver operating characteristic curves. After VS, PAOP and volume changes equally correlated to CI changes. After CAS, only changes in CVP and volumes correlated to those in CI. CONCLUSIONS While volumes are equally useful in monitoring fluid responsiveness, the predictive and monitoring value of PAOP is greater after VS than after CAS. In contrast, the CVP is of similar value as volume measurements in monitoring fluid responsiveness after CAS. The different value of pressures rather than of volumes between surgery types is likely caused by systolic left ventricular dysfunction in VS. The study suggests an effect of systolic cardiac function on optimal parameters of fluid responsiveness and superiority of the pulmonary artery catheter over transpulmonary dilution, for haemodynamic monitoring of VS patients.

Defining Fluid Responsiveness: A Guide to Patient-Tailored Volume Titration

FLUID RESPONSIVENESS is a strategy used to select patients who will respond with a positive reaction in a physiologic parameter upon fluid administration. Curiously, there is no generally accepted definition of fluid responsiveness. A provisional definition of fluid responsiveness would be “the positive reaction of a physiologic parameter of a certain size to a standardized volume of a certain type of fluid administered within a certain amount of time and measured within a certain interval.” It is clear that these issues need to be resolved before a more detailed and precise definition can be proposed. The aim of predicting fluid responsiveness is to achieve this positive reaction while using the least amount of fluids. Accurate prediction of fluid responsiveness to facilitate patient-tailored fluid titration is crucial, as it has been shown that only half of critically ill patients will respond to fluid loading with an increase in cardiac output. Moreover, unnecessary fluid administration has shown to increase morbidity, mortality, and hospital and intensive care stays. Over the last decade, the rise in the number of publications about fluid responsiveness in the intensive care and operating room has shown the increased interest in this topic. In this review, the authors describe the physiology, requirements, and limitations of fluid responsiveness. Subsequently, using available literature, a practical definition on fluid responsiveness is proposed. The reliability of clinical, static, and hemodynamic parameters is evaluated to predict the response to fluid loading in critically ill patients. Finally, the potential, shortcomings, and use of passive leg raising are discussed in this review.

Predicting outcome of rethoracotomy for suspected pericardial tamponade following cardio-thoracic surgery in the intensive care unit

ObjectivesPericardial tamponade after cardiac surgery is difficult to diagnose, thereby rendering timing of rethoracotomy hard. We aimed at identifying factors predicting the outcome of surgery for suspected tamponade after cardio-thoracic surgery, in the intensive care unit (ICU).MethodsTwenty-one consecutive patients undergoing rethoracotomy for suspected pericardial tamponade in the ICU, admitted after primary cardio-thoracic surgery, were identified for this retrospective study. We compared patients with or without a decrease in severe haemodynamic compromise after rethoracotomy, according to the cardiovascular component of the sequential organ failure assessment (SOFA) score.ResultsA favourable haemodynamic response to rethoracotomy was observed in 11 (52%) of patients and characterized by an increase in cardiac output, and less fluid and norepinephrine requirements. Prior to surgery, the absence of treatment by heparin, a minimum cardiac index < 1.0 L/min/m2 and a positive fluid balance (> 4,683 mL) were predictive of a beneficial haemodynamic response. During surgery, the evacuation of clots and > 500 mL of pericardial fluid was associated with a beneficial haemodynamic response. Echocardiographic parameters were of limited help in predicting the postoperative course, even though 9 of 13 pericardial clots found at surgery were detected preoperatively.ConclusionClots and fluids in the pericardial space causing regional tamponade and responding to surgical evacuation after primary cardio-thoracic surgery, are difficult to diagnose preoperatively, by clinical, haemodynamic and even echocardiographic evaluation in the ICU. Only absence of heparin treatment, a large positive fluid balance and low cardiac index predicted a favourable haemodynamic response to rethoracotomy. These data might help in deciding and timing of reinterventions after primary cardio-thoracic surgery.

Safety and efficacy of amphotericin-B deoxycholate inhalation in critically ill patients with respiratory Candida spp. colonization: a retrospective analysis

BackgroundCandida spp. are frequently cultured from the respiratory tract in critically ill patients. Most intensivists start amphotericin-B deoxycholate (ABDC) inhalation therapy to eradicate Candida spp. from the respiratory tract. However, the safety and efficacy of this treatment are not well established. The purpose of this study was to assess the safety and efficacy of ABDC inhalation for the treatment of respiratory Candida spp. colonization in critically ill patients.MethodsAll non-neutropenic patients admitted into the intensive care unit (ICU) of a university hospital from December 2010–2011, who had positive Candida spp. cultures of the respiratory tract for more than 1 day and required mechanical ventilation >48 h were retrospectively included. The decision to start ABDC inhalation had been made by attending intensivists on clinical grounds in the context of selective decontamination of the digestive tract. Infection characteristics and patient courses were assessed.ResultsHundred and thirteen consecutive patients were studied. Fifty-one of them received ABDC inhalation and their characteristics at baseline and day 1 of respiratory colonization did not differ from those of colonized patients not receiving treatment (n = 62). The ABDC-treated group had a similar Candida spp. load but did not decolonize more rapidly as compared to untreated patients. The clinical pulmonary infection and lung injury scores did not decrease as in the untreated group. In a Cox proportional hazard model, the duration of mechanical ventilation was increased (P < 0.003) by ABDC treatment independently of other potential determinants and Candida spp. colonization. No differences in ventilator-associated pneumonia or in overall mortality (up to day 90) were observed.ConclusionTreatment of respiratory Candida spp. colonization in non-neutropenic critically ill patients by inhaled ABDC may not affect respiratory colonization but may increase duration of mechanical ventilation, because of direct toxicity of the drug on the lung.

Pulse pressure variation does not reflect stroke volume variation in mechanically ventilated rats with lipopolysaccharide-induced pneumonia.

The present study examined the relationship between centrally measured stroke volume variation (SVV) and peripherally derived pulse pressure variation (PPV) in the setting of increased total arterial compliance (CArt). Ten male Wistar rats were anaesthetized, paralysed and mechanically ventilated before being randomized to receive intrapulmonary lipopolysaccharide (LPS) or no LPS. Pulse pressure (PP) was derived from the left carotid artery, whereas stroke volume (SV) was measured directly in the left ventricle. Values of SVV and PPV were calculated over three breaths. Balloon inflation of a catheter positioned in the inferior vena cava was used, for a maximum of 30 s, to decrease preload while the SVV and PPV measurements were repeated. Values of CArt were calculated as SV/PP. Intrapulmonary LPS increased CArt and SV. Values of SVV and PPV increased in both LPS‐treated and untreated rats during balloon inflation. There was a correlation between SVV and PPV in untreated rats before (r = 0.55; P = 0.005) and during (r = 0.69; P < 0.001) occlusion of the vena cava. There was no such correlation in LPS‐treated rats either before (r = −0.08; P = 0.70) or during (r = 0.36; P = 0.08) vena cava occlusion. In conclusion, under normovolaemic and hypovolaemic conditions, PPV does not reflect SVV during an increase in CArt following LPS‐induced pneumonia in mechanically ventilated rats. Our data caution against their interchangeability in human sepsis.

Impact of Positive End-Expiratory Pressure on Thermodilution-Derived Right Ventricular Parameters in Mechanically Ventilated Critically Ill Patients

OBJECTIVES To examine the effect of positive end-expiratory pressure (PEEP) on right ventricular stroke volume variation (SVV), with possible implications for the number and timing of pulmonary artery catheter thermodilution measurements. DESIGN Prospective, clinical pilot study. SETTING Academic medical center. PARTICIPANTS Patients who underwent volume-controlled mechanical ventilation and had a pulmonary artery catheter. INTERVENTION PEEP was increased from 5-to-10 cmH2O and from 10-to-15 cmH2O with 10-minute intervals, with similar decreases in PEEP, from 15-to-10 cmH2O and 10-to-5 cmH2O. MEASUREMENTS AND MAIN RESULTS In 15 patients, right ventricular parameters were measured using thermodilution at 10% intervals of the ventilatory cycle at each PEEP level with a rapid-response thermistor. Mean right ventricular stroke volume and end-diastolic volume declined during incremental PEEP and normalized on return to 5 cmH2O PEEP (p = 0.01 and p = 0.001, respectively). Right ventricular SVV remained unaltered by changes in PEEP (p = 0.26), regardless of incremental PEEP (p = 0.15) or decreased PEEP (p = 0.12). The coefficients of variation in the ventilatory cycle of all other thermodilution-derived right ventricular parameters also were unaffected by changes in PEEP. CONCLUSIONS This study showed that increases in PEEP did not affect right ventricular SVV in critically ill patients undergoing mechanical ventilation despite reductions in mean right ventricular stroke volume and end-diastolic volume. This could be explained by cyclic counteracting changes in right ventricular preloading and afterloading during the ventilatory cycle, independent of PEEP. Changes in PEEP did not affect the number and timing of pulmonary artery catheter thermodilution measurements.

Future Research Questions

The chapters of this section give an excellent overview of the current treatment of drowning in the hospital, but many questions related to the formal proof of certain interventions remain. Some of the controversial issues that deserve further testing, in a prospective manner, regardless of study design and possibility, include the following, in descending order of perceived priority.