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Marcus J Schultz

Publications and source records attributed to Marcus J Schultz.

At least 19 recordsLinked to original sources
PubMed2026

Alarms and alarm management with automated versus conventional ventilation in neurocritical care patients.

INTRODUCTION: False or clinically irrelevant alarms are a major driver of ICU alarm fatigue and nursing workload. Ventilator alarms make up a large share, and although automated ventilation modes can reduce manual adjustments, their effect on alarm burden is still unclear. This issue can be particularly relevant in neurocritical care patients, where precise ventilator and alarm management is imperative for patient safety. OBJECTIVES: This explorative post hoc analysis of a randomized clinical trial compared alarm frequency and management between automated ventilation and conventional ventilation in neurocritical care patients. METHODS: Ventilator alarms and manual ventilator changes were captured continuously from the ventilator for up to 24 h per patient. The primary endpoint was a composite of workload-relevant alarms; with alarm management interventions at the ventilator as a key secondary outcome. Additional endpoints included redundant alarms, alarm duration and ventilator management. RESULTS: 13 patients received automated ventilation and 24 received conventional ventilation. No difference was observed in workload-relevant alarm frequency between automated and conventional ventilation (3.28 [2.87 to 4.30] vs 3.73 [1.66 to 7.33] alarms per hour; P = 0.81), while alarm management interventions at the ventilator were lower with automated ventilation (0.14 [0.10 to 0.15] vs 0.21 [0.17 to 0.31] interventions per hour; P = 0.01). Other alarm frequencies, duration of alarms and ventilator management were similar. CONCLUSIONS: In this exploratory post hoc analysis of a randomized clinical trial in neurocritical care patients during the early phase of mechanical ventilation, automated ventilation did not reduce the frequency of total or workload-relevant alarms, nor their duration, but was associated with fewer alarm management interventions compared to conventional ventilation. IMPLICATIONS FOR CLINICAL PRACTICE: Automated ventilation may not reduce alarm frequency in neurocritical care patients, but the observed reduction in alarm-related bedside interventions suggests a potential benefit for nursing workload.

Humans↗
PubMed2007

Procoagulant and fibrinolytic activity in cerebrospinal fluid from adults with bacterial meningitis.

OBJECTIVES: This study investigated levels of coagulation and fibrinolysis factors in cerebrospinal fluid (CSF) from adults with bacterial meningitis in relation to development of brain infarction. METHODS: CSF was collected from 92 adults with community-acquired bacterial meningitis, who participated in the prospective Dutch Meningitis Cohort Study; 8 patients with viral meningitis and 9 healthy control subjects. Levels of proteins involved in the coagulation cascade were determined by means of immunoassays. RESULTS: Bacterial meningitis was accompanied by local activation of coagulation, as shown by significantly higher CSF soluble tissue factor (P<0.001) and prothrombin fragment F1+2 concentrations (P<0.001) as compared to viral meningitis patients and controls. This was accompanied by a significantly higher D-dimer formation (P<0.001). In addition, in bacterial meningitis fibrinolysis was attenuated, since CSF plasminogen activator inhibitor (PAI)-1 levels were significantly higher as compared to the controls (P=0.02). In patients with bacterial meningitis who developed brain infarction, CSF PAI-1 levels were higher than in those without infarction (P=0.04). CONCLUSIONS: Activation of coagulation and attenuation of fibrinolysis in the CSF are important features of bacterial meningitis; the net effect on fibrin turnover may contribute to the development of brain infarction.

Adolescent↗
PubMed2007

Clinical and hemostatic responses to treatment in ventilator-associated pneumonia: role of bacterial pathogens.

OBJECTIVE: To determine pathogen-specific kinetic changes in the alveolar procoagulant (PC) activity, tissue factor (TF), and tissue factor pathway inhibitor (TFPI) expression during the course of ventilator-associated pneumonia (VAP) and to assess the relationship between clinical resolution, intra-alveolar bacterial eradication, and restoration of hemostatic balance. DESIGN: Prospective, multiple-center study in a cohort of VAP patients. SETTING: Two university-affiliated intensive care units. PATIENTS: Thirty-five patients with microbiologically documented VAP who received adequate antimicrobial coverage and 13 controls. INTERVENTIONS: Nonbronchoscopic bronchoalveolar lavage was performed at the onset of VAP and on days 4 and 8 after initiation of antibiotic therapy. Samples were assayed for PC, TF, TFPI, and thrombin-antithrombin complex (TATc). The corresponding Clinical Pulmonary Infection Score (CPIS) was collected simultaneously. MEASUREMENTS AND MAIN RESULTS: Isolated pathogens included Pseudomonas aeruginosa (n=13), methicillin-resistant Staphylococcus aureus (MRSA) (n=8), methicillin-sensitive S. aureus (MSSA) (n=7), and Escherichia coli (n=7). Although PC activity and TF were increased among the various pathogens at the onset of VAP, the levels of those with P. aeruginosa remained elevated at the end of treatment compared with controls and other etiological agents. TFPI levels were elevated for the duration of the study for all pathogens. A universal increase in TATc was noted at the onset of VAP, but the difference among the group of pathogens was significant at days 4 and 8 posttherapy. Despite the persisting hemostatic imbalance and incomplete intra-alveolar eradication of P. aeruginosa at end of therapy, the CPIS fell comparably at each time point irrespective of the etiological agents. CONCLUSIONS: Alveolar activation of the TF-dependent pathway may be species-specific in VAP and may not be adequately balanced by TFPI. The disparity between clinical response and eradication of P. aeruginosa from the intra-alveolar space suggests the need for biological markers to guide response to therapy.

Aged↗
PubMed2006

Discrepancies between observed and predicted continuous venovenous hemofiltration removal of antimicrobial agents in critically ill patients and the effects on dosing.

OBJECTIVE: Drug dosing during continuous venovenous hemofiltration (CVVH) is based partly upon the CVVH clearance (Cl(CVVH)) of the drug. Cl(CVVH) is the product of the sieving coefficient (SC) and ultrafiltration rate (Q(uf)). Although it has been suggested that the SC can be replaced by the fraction of a drug not bound to protein (F(up)), the F(up) values as reported in the literature may not reflect the protein binding in critically ill patients with renal failure. We compared the observed Cl(CVVH) (SC x Q(uf)) with the estimated Cl(CVVH) (estimated F(UP) x Q(uf)) and determined the effect on the maintenance dose multiplication factor (MDMF). DESIGN AND SETTING: Clinical study in a mixed ICU in a university hospital. PATIENTS: 45 oligoanuric patients on CVVH (2 l/h). INTERVENTIONS: Timed blood and ultrafiltrate samples. MEASUREMENTS AND RESULTS: Amoxicillin, ceftazidime, ciprofloxacin, fluconazole, metronidazole, and vancomycin were easily filtered (mean SC > 0.7) but not flucloxacillin (mean SC 0.3). Predicted and observed Cl(CVVH) corresponded only for fluconazole and metronidazole. The difference between observed and predicted MDMF was small for all drugs, with the exception of ceftazidime (mean 0.25, 95% CI -0.96 to 1.48) and vancomycin (0.05, -1.34 to 1.45). However, this difference was clinically relevant only for vancomycin, because of its narrow therapeutic index. CONCLUSIONS: Dosing based on predicted CVVH removal provides an as reliable estimate than that based on observed CVVH removal except for those antibiotics that have both a narrow therapeutic index and a predominantly renal clearance (e.g., vancomycin).

APACHE↗
PubMed2006

Early procoagulant shift in the bronchoalveolar compartment of patients with secondary peritonitis.

BACKGROUND: In acute respiratory distress syndrome or pneumonia, a procoagulant shift is observed in bronchoalveolar lavage fluid (BALF). The effect of a primarily extrapulmonary infection on coagulation and fibrinolysis in the pulmonary compartment is unclear. METHODS: In 35 patients, 87 bronchoalveolar lavages were performed on the day of operation for secondary peritonitis (day 0) and on days 2 and 3 after surgery. Two noninfectious control groups were included: subjects undergoing bronchoalveolar lavage after elective surgery (n=8) and those undergoing long-term mechanical ventilation (n=10). RESULTS: In BALF from patients with peritonitis, a tissue factor (TF)/factor VIIa-mediated activation of coagulation was shown (high levels of thrombin-antithrombin complexes). Levels of fibrinolysis activators decreased rapidly after day 0, whereas levels of inhibitors increased. The net effect was reduced fibrinolysis (plasminogen activator activity). The sequential comparison of plasma levels of TF pathway inhibitor showed higher levels in patients who died (28-day mortality; P<.001). Sequential levels of TF in BALF were higher in patients with low PaO2 : FiO2 ratios (<200; P=.039). Differences between patients and control subjects were more pronounced in BALF than in plasma. CONCLUSIONS: Secondary peritonitis induces an early activation of the coagulation and inhibition of fibrinolysis in the systemic and bronchoalveolar compartments, possibly via a compartmentalized response. This imbalance may be associated with reduced oxygen delivery and an adverse outcome in secondary peritonitis.

Aged↗
PubMed2006

Chest radiography practice in critically ill patients: a postal survey in the Netherlands.

BACKGROUND: To ascertain current chest radiography practice in intensive care units (ICUs) in the Netherlands. METHODS: Postal survey: a questionnaire was sent to all ICUs with > 5 beds suitable for mechanical ventilation; pediatric ICUs were excluded. When an ICU performed daily-routine chest radiographs in any group of patients it was considered to be a "daily-routine chest radiography" ICU. RESULTS: From the number of ICUs responding, 63% practice a daily-routine strategy, in which chest radiographs are obtained on a daily basis without any specific reason. A daily-routine chest radiography strategy is practiced less frequently in university-affiliated ICUs (50%) as compared to other ICUs (68%), as well as in larger ICUs (> 20 beds, 50%) as compared to smaller ICUs (< 20 beds, 65%) (P > 0.05). Remarkably, physicians that practice a daily-routine strategy consider daily-routine radiographs helpful in guiding daily practice in less than 30% of all performed radiographs. Chest radiographs are considered essential for verification of the position of invasive devices (81%) and for diagnosing pneumothorax, pneumonia or acute respiratory distress syndrome (82%, 74% and 69%, respectively). On demand chest radiographs are obtained after introduction of thoracic drains, central venous lines and endotracheal tubes in 98%, 84% and 75% of responding ICUs, respectively. Chest films are also obtained in case of ventilatory deterioration (49% of responding ICUs), and after cardiopulmonary resuscitation (59%), tracheotomy (58%) and mini-tracheotomy (23%). CONCLUSION: There is notable lack of consensus on chest radiography practice in the Netherlands. This survey suggests that a large number of intensivists may doubt the value of daily-routine chest radiography, but still practice a daily-routine strategy.

Journal Article↗
PubMed2006

Soluble triggering receptor expressed on myeloid cells 1: a biomarker for bacterial meningitis.

OBJECTIVE: To evaluate whether soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) in CSF can serve as a biomarker for the presence of bacterial meningitis and outcome in patients with this disease. DESIGN: Retrospective study of diagnostic accuracy. SETTING AND PATIENTS: CSF was collected from 92 adults with community-acquired bacterial meningitis who participated in the prospective Dutch Meningitis Cohort Study; 8 patients with viral meningitis and 9 healthy control subjects. RESULTS: CSF sTREM-1 levels were higher in patients with bacterial meningitis (median 82 pg/ml, range 0-988) than in those with viral meningitis (0 pg/ml, 0-48) and controls (0 pg/ml, 0-36). The diagnostic accuracy of sTREM-1 in discriminating between patients with and without bacterial meningitis, expressed as the area under the receiver operating characteristic curve, was 0.82. At a cutoff level of 20 pg/ml the sensitivity was 0.73 and specificity 0.77. In patients with bacterial meningitis CSF sTREM-1 levels were associated with mortality (survivors, median 73 pg/ml, range 0-449 pg/ml; nonsurvivors, 15 pg/ml, 0-988). CONCLUSIONS: Measuring sTREM-1 in CSF may be a valuable new additional approach to accurately diagnose bacterial meningitis and identify patients at high risk for adverse outcome. Therefore a prospective study of sTREM-1 as a biomarker in bacterial meningitis is needed.

Biomarkers↗
PubMed2006

Influence of severity of illness, medication and selective decontamination on defecation.

OBJECTIVE: To describe the pattern of defecation in critically ill ventilated patients and the influence of selective decontamination (SDD) and other medication. DESIGN: Descriptive cohort study. SETTING: Mixed surgical-medical ICU in a university Hospital. PATIENTS: Ventilated patients with a length of stay >or=7 days taking part in a study on SDD. MEASUREMENTS: Daily registration of defecation, SOFA (sepsis-related organ failure assessment score) score, administration of dopamine, noradrenaline, morphine and other medications. RESULTS: The first defecation occurred after a mean of 6.2 days. Patients with defecation within 6[Symbol: see text]days had lower mean SOFA scores, received more cisapride and lactulose and less dopamine, noradrenaline and morphine, and had a shorter duration of mechanical ventilation and ICU stay. On 57% of the days, no stools were produced; on 31% diarrhea, and on 12%, normal stools. Patients receiving SDD had more days with normal stools and less with diarrhea. Diarrhea was preceded by the administration of lactulose in the majority of patients. CONCLUSION: Time to first defecation correlated with severity of illness, vasoactive medication, administration of morphine, cisapride and lactulose, duration of mechanical ventilation and length of stay. Diarrhea seemed at least partially iatrogenic.

Adult↗
PubMed2006

Bench to bedside: targeting coagulation and fibrinolysis in acute lung injury.

Substantial progress has been made in understanding the contribution of alterations in coagulation and fibrinolysis to the pathogenesis of acute lung injury (ALI). Findings from mouse, rat, baboon, and human studies indicate that alterations in coagulation and fibrinolysis may be of major pathogenetic importance in ALI and other inflammatory conditions in the lung including pneumonia, sepsis, and ventilator-induced lung injury. Therapies targeted at both activation of coagulation through the extrinsic coagulation cascade and modulation of coagulation through the protein C system have the potential to favorably impact clinical ALI/acute respiratory distress syndrome.

Animals↗
PubMed2006

The relationship between inflammation and the coagulation system.

Inflammation and coagulation play pivotal roles in host defence. As phylogenetically old responses, there is extensive cross-talk between inflammation and coagulation in enabling an adequate immune response against potentially injurious stimuli. Immune cells are important in the initiation of coagulation pathways, while various inflammatory mediators are capable of altering haemostasis. Vice versa, coagulation proteases have significant immunomodulatory effects. Understanding the mechanisms involved in the crosstalk between inflammation and coagulation may yield new therapeutic strategies for human diseases.

Blood Coagulation↗
PubMed2006

A change in the Dutch Directive on Medical Research Involving Human Subjects strongly increases the number of eligible intensive care patients: an observational study.

OBJECTIVES: To determine the effect of a change in the "Dutch Directive on Medical Research Involving Human Subjects" (DD) on the number of eligible intensive care unit (ICU) patients for medical research. In addition, we determined how family members experience their role as acting representative for giving informed consent, and in turn whether patients feel their representatives would do well representing them. DESIGN AND SETTING: Prospective observational study in three Dutch ICUs. PARTICIPANTS: 714 consecutive ICU patients. Analysis was restricted to 211 patients who were incapacitated for more than 24h after ICU admission. MEASUREMENTS AND RESULTS: The old DD left 45.5% of patients without a legal representative; with the new DD this figure declines to 8.1%. Older age was significantly associated with the impossibility of obtaining informed consent in the old DD; after the change there was no effect of age. The median grade of confidence that representatives had in giving informed consent for incapacitated patients was 8.0 (IQR 7.0-9.0) on a scale from 0 to 10. Patients gave an equal median grade to their representatives. CONCLUSION: When patients' adult children are not legally allowed to give informed consent, older patients are excluded from medical research, causing selection bias. The change in the DD has increased the number of surrogates allowed to give informed consent. Representatives felt very confident in their ability to represent the patients. In turn patients were equally confident that their representatives were able to represent them.

Adult↗
PubMed2006

Mechanical ventilation with lower tidal volumes and positive end-expiratory pressure prevents alveolar coagulation in patients without lung injury.

BACKGROUND: Alveolar fibrin deposition is a hallmark of acute lung injury, resulting from activation of coagulation and inhibition of fibrinolysis. Previous studies have shown that mechanical ventilation with high tidal volumes may aggravate lung injury in patients with sepsis and acute lung injury. The authors sought to determine the effects of mechanical ventilation on the alveolar hemostatic balance in patients without preexistent lung injury. METHODS: Patients scheduled for an elective surgical procedure (lasting > or = 5 h) were randomly assigned to mechanical ventilation with either higher tidal volumes of 12 ml/kg ideal body weight and no positive end-expiratory pressure (PEEP) or lower tidal volumes of 6 ml/kg and 10 cm H2O PEEP. After induction of anesthesia and 5 h later bronchoalveolar lavage fluid and blood samples were obtained, and markers of coagulation and fibrinolysis were measured. RESULTS: In contrast to mechanical ventilation with lower tidal volumes and PEEP (n = 21), the use of higher tidal volumes without PEEP (n = 19) caused activation of bronchoalveolar coagulation, as reflected by a marked increase in thrombin-antithrombin complexes, soluble tissue factor, and factor VIIa after 5 h of mechanical ventilation. Mechanical ventilation with higher tidal volumes without PEEP caused an increase in soluble thrombomodulin in lavage fluids and lower levels of bronchoalveolar activated protein C in comparison with lower tidal volumes and PEEP. Bronchoalveolar fibrinolytic activity did not change by either ventilation strategy. CONCLUSIONS: Mechanical ventilation with higher tidal volumes and no PEEP promotes procoagulant changes, which are largely prevented by the use of lower tidal volumes and PEEP.

Aged↗
PubMed2006

Predisposing factors for hypoglycemia in the intensive care unit.

OBJECTIVE: The introduction of strict glycemic control in the intensive care unit has increased the risk for hypoglycemia. In this study we examined the association between predefined circumstances and the occurrence of hypoglycemia in the intensive care unit. DESIGN: : Retrospective cohort study. SETTING: Academic medical center. PATIENTS: All episodes of hypoglycemia (glucose value <45 mg/dL) in our intensive care unit between September 2002 and September 2004 were identified. Presence of predefined circumstances previously associated with hypoglycemia was scored around the moment of hypoglycemia using a patient data management system and in-hospital charts. Patients with a first hypoglycemic event were contrasted to controls from the same cohort, who were matched for time since admission, to correct for the effect of length of stay. Data were analyzed using conditional logistic regression analysis. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 2,272 patients, 156 (6.9%) experienced at least one episode of hypoglycemia. Continuous venovenous hemofiltration with bicarbonate-based substitution fluid (odds ratio [OR], 14; 95% confidence interval [CI], 1.8-106), a decrease of nutrition without adjustment for insulin infusion (OR, 6.6; 95% CI, 1.9-23), diabetes mellitus (OR, 2.6; 95% CI, 1.5-4.7), insulin use (OR, 5.3; 95% CI, 2.8-11), sepsis (OR, 2.2; 95% CI, 1.2-4.1), and inotropic support (OR, 1.8; 95% CI, 1.1-2.9) were associated with hypoglycemia. Simultaneous octreotide and insulin use (OR, 6.0; 95% CI, 0.72-50) may also be associated with hypoglycemia. Gastric residual during enteral nutrition without adjusting insulin infusion, liver failure, continuous venovenous hemofiltration with lactate-based substitution fluid, diminished glomerular filtration rate, dose diminishment of glucocorticoids or catecholamines, and use of beta-blocking agents were not associated with hypoglycemia. Adjusting for age, gender, and Acute Physiology and Chronic Health Evaluation II score at admission did not materially change ORs. CONCLUSION: Use of bicarbonate-based substitution fluid during continuous venovenous hemofiltration, a decrease of nutrition without adjustment for insulin infusion, a prior diagnosis of diabetes mellitus, sepsis, and need for inotropic support were found to be associated with hypoglycemia. Simultaneous use of insulin and octreotide may be associated with hypoglycemia.

Adult↗