Automated mechanical cardiopulmonary resuscitation devices versus manual chest compressions in the treatment of cardiac arrest: protocol of a systematic review and meta-analysis comparing machine to human

INTRODUCTION

Cardiac arrest is a leading cause of death in industrialised countries. Cardiopulmonary resuscitation (CPR) guidelines follow the principles of closed chest compression as described for the first time in 1960. Mechanical CPR devices are designed to improve chest compression quality, thus considering the improvement of resuscitation outcomes. This protocol outlines a systematic review and meta-analysis methodology to assess trials investigating the therapeutic effect of automated mechanical CPR devices at the rate of return of spontaneous circulation, neurological state and secondary endpoints (including short-term and long-term survival, injuries and surrogate parameters for CPR quality) in comparison with manual chest compressions in adults with cardiac arrest.

METHODS AND ANALYSIS

A sensitive search strategy will be employed in established bibliographic databases from inception until the date of search, followed by forward and backward reference searching. We will include randomised and quasi-randomised trials in qualitative analysis thus comparing mechanical to manual CPR. Studies reporting survival outcomes will be included in quantitative analysis. Two reviewers will assess independently publications using a predefined data collection form. Standardised tools will be used for data extraction, risks of bias and quality of evidence. If enough studies are identified for meta-analysis, the measures of association will be calculated by dint of bivariate random-effects models. Statistical heterogeneity will be evaluated by I²-statistics and explored through sensitivity analysis. By comprehensive subgroup analysis we intend to identify subpopulations who may benefit from mechanical or manual CPR techniques. The reporting follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

ETHICS AND DISSEMINATION

No ethical approval will be needed because data from previous studies will be retrieved and analysed. Most resuscitation studies are conducted under an emergency exception for informed consent. This publication contains data deriving from a dissertation project. We will disseminate the results through publication in a peer-reviewed journal and at scientific conferences.

PROSPERO REGISTRATION NUMBER

CRD42017051633.

Effect of physostigmine on recovery from septic shock following intra-abdominal infection - Results from a randomized, double-blind, placebo-controlled, monocentric pilot trial (Anticholium® per Se)

PURPOSE

The cholinergic anti-inflammatory pathway has been shown to be accessible by physostigmine salicylate in animal models. However, the cholinesterase inhibitor is not approved for adjunctive therapy in sepsis, and tolerability and safety of high initial doses followed by continuous infusion have not been investigated.

MATERIALS AND METHODS

In this trial, 20 patients with perioperative septic shock due to intra-abdominal infection were eligible. The physostigmine group received an initial dose of 0.04 mg/kg physostigmine salicylate, followed by continuous infusion of 1 mg/h for 120 h; the placebo group was treated with 0.9% sodium chloride. Primary outcome was the mean Sequential Organ Failure Assessment (SOFA) score during treatment and up to 14 days.

RESULTS

Administration of physostigmine salicylate was well tolerated. Mean SOFA scores were 8.9 ± 2.5 and 11.3 ± 3.6 (mean ± SD) for physostigmine and placebo group, respectively. Adjusted for age, difference between means was not statistically significant (-2.37, 95% CI: -5.43 to 0.70, p = 0.121). Norepinephrine doses required only appeared lower in the physostigmine group (p = 0.064), along with a more rapid reduction from an elevated heart rate possibly indicating less hemodynamic instability.

CONCLUSIONS

Treatment with physostigmine salicylate was feasible and safe. Further studies are justified to assess the effect on recovery from septic shock.

TRIAL REGISTRATION

EudraCT Number 2012-001650-26, ClinicalTrials.gov identifier NCT03013322.

Adjunctive use of physostigmine salicylate (Anticholium®) in perioperative sepsis and septic shock: study protocol for a randomized, double-blind, placebo-controlled, monocentric trial (Anticholium® per Se)

Background

Severe sepsis and septic shock remain a major challenge, even in modern intensive care. In Germany, about 68,000 patients die annually because of septic diseases, characterized by a complex systemic inflammatory response. Causal treatment of the underlying infection is essential for successful management of sepsis, but the course can be positively influenced by supportive and adjuvant measures. The cholinergic anti-inflammatory pathway (CAP) represents a new approach to adjunctive therapy of septic diseases and can be pharmacologically activated by the acetylcholinesterase inhibitor physostigmine (Anticholium®). Promising effects can be found in several in vitro and in vivo models of sepsis, such as a reduction in pro-inflammatory cytokines and improved survival.

Methods

Anticholium® per Se is a randomized, double-blind, placebo-controlled, monocentric trial to assess whether the CAP can be transferred from bench to bedside. In this pilot study, 20 patients with perioperative sepsis and septic shock as a result of intra-abdominal infection are enrolled. According to randomization, participants are treated with physostigmine salicylate (verum group) or 0.9% sodium chloride (placebo group) for up to 5 days. The mean Sequential Organ Failure Assessment (SOFA) score during treatment and subsequent intensive care of up to 14 days is used as surrogate outcome (primary endpoint). Secondary outcome measures include 30- and 90-day mortality. An embedded pharmacokinetics and pharmacodynamics study investigates plasma concentrations of physostigmine and its metabolite eseroline. Further analyses will contribute to our understanding of the role of various cytokines in the pathophysiology of human sepsis. A computer-generated list is used for block randomization.

Discussion

This randomized, controlled, monocentric trial investigates for the first time the adjunctive use of physostigmine (Anticholium®) in patients with perioperative sepsis and septic shock and may be a pivotal step toward the clinical use in this indication.

Trial registration

EudraCT Number: 2012-001650-26 (entered 14 August 2012), ClinicalTrials.gov identifier: NCT03013322 (registered on 1 Jan 2017).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2231-x) contains supplementary material, which is available to authorized users.

Revival of physostigmine – a novel HPLC assay for simultaneous determination of physostigmine and its metabolite eseroline designed for a pharmacokinetic study of septic patients

Physostigmine, commonly used as an antidote in anticholinergic poisoning, is reported to have additional pharmacological effects, such as activation of the cholinergic anti-inflammatory pathway in sepsis models. Due to the narrow therapeutic range of physostigmine and its metabolite eseroline, however, the plasma concentrations of these substances need to be determined so as to understand their effect and ensure safety in the treatment of septic patients.

To determine physostigmine and its metabolite eseroline, a rapid and sensitive high performance liquid chromatography (HPLC) method has been developed and validated. Spiked plasma samples were cleaned up and concentrated using a simple liquid-liquid extraction (LLE) procedure with N-methylphysostigmine as internal standard. Separation was achieved using reversed-phase HPLC on a Kinetex C18 column with gradient elution and fluorescence detection (254 nm excitation/355 nm emission).

LLE produced clean extracts and a mean recovery of 80.3% for eseroline and 84.9% for physostigmine. The HPLC assay revealed a limit of detection (LOD) of 0.025 ng/mL and a lower limit of quantification (LLOQ) of 0.05 ng/mL for both analytes. Linearity was observed at 0.05–10.0 ng/mL (r

The presented method is useful for human drug level monitoring of physostigmine and eseroline in accordance with current guidelines. Remarkably low plasma concentrations can be quantified after LLE with gradient elution and fluorescence detection, making this a suitable method for pharmacokinetic studies in a clinical setting.

Comparative study of prescribing patterns of tigecycline for trial patients versus non-trial patients

BACKGROUND

Comparing published trial patients and non-trial patients in clinical practice, clinicians often doubt whether critically ill patients are sufficiently represented in randomised clinical trials.

PATIENTS AND METHODS

This study evaluated the extent of infection with multidrug-resistant (MDR) pathogens, anti-microbial combination therapy, off-label use and targeted-treatment in trial patients versus non-trial patients.

RESULTS

Tigecycline therapy was prescribed for off-label use in more than half of the non-trial patients; 77% of trial patients received study medication as first-line therapy in contrast to 25% of non-trial patients (p<0.001). Tigecycline therapy was targeted for 27% of trial patients versus 73% of non-trial patients (p<0.001). Ninety-six percent of non-trial patients were treated for nosocomial infections compared to 23% of trial patients (p<0.001). In one out of 22 (4.5%) trial patients an ESKAPE pathogen was found, whereas rates of vancomycin- resistant Enterococcus faecium, methicillin-resistant Staphylococcus aureus and extended spectrum-β lactamase- producing Enterobacteriaceae ranged between 13/165 (8%) and 23/165 (14%) for non-trial patients.

CONCLUSION

Tigecycline was used for less critical populations in clinical trials than in clinical practice. Our findings confirm the particular need of potent substances such as tigecycline for critically ill patients.

Patients enrolled in randomised clinical trials are not representative of critically ill patients in clinical practice: observational study focus on tigecycline

It is being increasingly recognised by clinicians and scientists that participants in randomised clinical trials (RCTs) of antibiotics of last resort do not represent the patients who will later be treated with these drugs. Data on this subject are limited and have not been investigated systematically. This observational study aimed to examine this hypothesis quantitatively, using the example of tigecycline. To evaluate the influence of recruitment, patients eligible for clinical trials were retrospectively compared with ineligible patients regarding baseline and clinical characteristics as well as outcome parameters, e.g. length of hospital stay, intensive care unit (ICU) stay, ventilation and mortality. The clinical characteristics of 187 patients illustrated differences in the nature and severity of disease, co-morbidities and outcome. Eligible and ineligible patients differed in a number of parameters, e.g. median APACHE II score (15.5 vs. 28.0), number of liver transplantations (5% vs. 18%; P=0.048), septic shock (21% vs. 49%; P=0.001), need for mechanical ventilation (30% vs. 79%; P<0.001), mean length of ICU stay (19.3 days vs. 40.7 days) and death (19% vs. 46%; P=0.001). Critically ill patients were under-represented in clinical trials. Moreover, only a minority of patients in clinical practice (13%) were potentially eligible for a pivotal RCT. The disparities likely result from strict exclusion criteria in RCTs and recruitment bias. These data emphasise the importance of including critically ill patients in RCTs of antibiotics against multiresistant bacteria in order to account for those who will later be treated.

Design of a prospective clinical study on the agreement between the Continuous GlucoseMonitor, a novel device for CONTinuous ASSessment of blood GLUcose levels, and the RAPIDLab® 1265 blood gas analyser: The CONTASSGLU study

Background

Although a device is needed to continuously measure blood glucose levels within an intensive care setting, and several large-scale prospective studies have shown that patients might benefit from intensive insulin, potassium, or glucose therapy during intensive care, no devices are currently available to continuously assess blood glucose levels in critically ill patients. We conceived the study described here to evaluate the clinical use of the Continuous Glucose Monitor (CGM) performed via a central vein, and to determine the impact of phenomena, such as drift and shift, on the agreement between the CGM and a RAPIDLab® 1265 blood gas analyser (BGA).

Methods/design

In the CONTinuous ASSessment of blood GLUcose (CONTASSGLU) study, up to 130 patients under intensive care will be fitted with the CGM, an ex vivo device that continuously measures blood glucose and lactate levels. Readings from the device taken 8 h after initial placement and calibration will be compared with values measured by a BGA. For this study, we chose the BGA as it is an established standard point-of-care device, instead of the devices used in certified central laboratories. Nevertheless, we will also independently compare the results from the point-of-care BGA with those determined by a central laboratory-based device. Blood samples will be collected from each patient from the same site in which the CGM will measure blood glucose. Consequently, each participant will serve as their own control, and no randomisation is necessary. The 95% limits of agreement and the corresponding confidence intervals will be calculated and compared with a prespecified clinically acceptable relative difference of 20%.

Discussion

Several attempts have been made to develop a device to continuously measure blood glucose levels within an intensive care setting or to use the devices that were originally designed for diabetes management, as several of these devices are already available. However, none of these devices were successful in intensive care settings. CONTASSGLU may well bridge this gap by confirming the ability of the CGM to continuously measure blood glucose levels in intensive care settings.

Trial registration

ClinicalTrials.gov NCT01580176

Ranking of patient and surgeons' perspectives for endpoints in randomized controlled trials--lessons learned from the POVATI trial [ISRCTN 60734227]

INTRODUCTION

Surgical trials focus mainly on mortality and morbidity rates, which may be not the most important endpoints from the patient's perspective. Evaluation of expectations and needs of patients enrolled in clinical trials can be analyzed using a procedure called ranking. Within the Postsurgical Pain Outcome of Vertical and Transverse Abdominal Incision randomized trial (POVATI), the perspectives of participating patients and surgeons were assessed as well as the influence of the surgical intervention on patients' needs.

PATIENTS AND METHODS

All included patients of the POVATI trial were asked preoperatively and postoperatively to rank predetermined outcome variables concerning the upcoming surgical procedure (e.g., pain, complication, cosmetic result) hierarchically according to their importance. Preoperatively, the surgeons were asked to do the same.

RESULTS

One hundred eighty two out of 200 randomized patients (71 females, 111 males; mean age 59 years) returned the ranking questionnaire preoperatively and 152 patients (67 females, 85 males; mean age 60 years) on the day of discharge. There were no differences between the two groups with respect to the distribution of ranking variables (p > 0.05). Thirty-five surgeons (7 residents, 6 fellows, and 22 consultants) completed the same ranking questionnaire. The order of the four most important ranking variables for both patients and surgeons were death, avoiding of postoperative complications, avoiding of intraoperative complications, and pain. Surgeons ranked the variable "cosmetic result" significantly as more important compared to patients (p = 0.034, Fisher's exact test).

CONCLUSION

Patients and surgeons did not differ in ranking predetermined outcomes in the POVATI trial. Only the variable "cosmetic result" is significantly more important from the surgeon's than from the patient's perspective. Ranking of outcomes might be a beneficial tool and can be a proper addition to RCTs.

IVC CLAMP: infrahepatic inferior vena cava clamping during hepatectomy--a randomised controlled trial in an interdisciplinary setting

BACKGROUND

Intraoperative haemorrhage is a known predictor for perioperative outcome of patients undergoing hepatic resection. While anaesthesiological lowering of central venous pressure (CVP) by fluid restriction is known to reduce bleeding during transection of the hepatic parenchyma its potential side effects remain poorly investigated. In theory it may have negative effects on kidney function and tissue perfusion and bears the risk to result in severe haemodynamic instability in case of profound intraoperative blood loss. The present randomised controlled trial evaluates efficacy and safety of infrahepatic inferior vena cava (IVC) clamping as an alternative surgical technique to reduce CVP during hepatic resection.

METHODS/DESIGN

The proposed IVC CLAMP trial is a single-centre randomised controlled trial with a two-group parallel design. Patients and outcome-assessors are blinded for the treatment intervention. Patients undergoing elective hepatic resection due to any reason are enrolled in IVC CLAMP. All patients admitted to the Department of General-, Visceral-, and Transplant Surgery, University of Heidelberg for elective hepatic resection are consecutively screened for eligibility and written informed consent is obtained on the day before surgery. The primary objective of this trial is to assess and compare the amount of blood loss during hepatic resection in patients receiving surgical CVP reduction by clamping of the IVC as compared to anaesthesiological CVP without infrahepatic IVC clamping reduction. In addition to blood loss a set of general as well as surgical variables are analysed.

DISCUSSION

This is a randomised controlled patient and observer blinded two-group parallel trial designed to assess efficacy and safety of infrahepatic IVC clamping during elective hepatectomy.

Meta-analysis of standard, restrictive and supplemental fluid administration in colorectal surgery

BACKGROUND

Optimal fluid therapy for colorectal surgery remains uncertain.

METHODS

A simple model was applied to define standard, restrictive and supplemental fluid administration. These definitions enabled pooling of data from different trials. Randomized controlled trials on fluid amount (standard versus restrictive or supplemental amount) and on guidance for fluid administration (goal-directed fluid therapy by oesophageal Doppler-derived variables versus conventional haemodynamic variables) in patients with colorectal resection were eligible for inclusion. The primary outcome measure was postoperative morbidity. Secondary endpoints were mortality, cardiopulmonary morbidity, wound infection, anastomotic failure, recovery of bowel function and hospital stay. A random-effects model was applied.

RESULTS

Nine randomized controlled trials were included. Restrictive fluid amount (odds ratio (OR) 0.41 (95 per cent confidence interval (c.i.) 0.22 to 0.77); P = 0.005) and goal-directed fluid therapy by means of oesophageal Doppler-derived variables (OR 0.43 (95 per cent c.i. 0.26 to 0.71); P = 0.001) significantly reduced overall morbidity. There were no significant differences in the secondary endpoints analysed.

CONCLUSION

Using standardized definitions, this meta-analysis suggests that restrictive rather than standard fluid amount according to current textbook opinion, and goal-directed fluid therapy rather than fluid therapy guided by conventional haemodynamic variables, reduce morbidity after colorectal resection.