Exploring the real-life value of first responders for out-of-hospital cardiac arrest in a Belgian urban context: a retrospective analysis

Bystander-initiated cardiopulmonary resuscitation can curb the deterioration of regional cerebral oxygen saturation on hospital arrival in patients with cardiac arrest

Substantial differences in survival after out-of-hospital cardiac arrest (OHCA) have been observed between countries. These might be attributed to the organization of emergency medical service (EMS) systems, including prehospital physician involvement. However, limited data exist on the physician's role in improving survival after OHCA. To compare prehospital and in-hospital outcomes of OHCA patients attended by physician-staffed EMS vs. paramedic-staffed EMS units. Among all patients enrolled in the regional, prospective registry of OHCA in southern Poland, we excluded those aged <18 years, with unwitnessed or EMS-witnessed cardiac arrest, without attempted cardiopulmonary resuscitation (CPR), attended by more than one EMS, or with traumatic cardiac arrest. The groups were matched 1:1 using propensity scores for baseline characteristic variables that might influence physician-staffed EMS dispatch. A total of 812 OHCA cases were included in the current analysis. Among them, 351 patients were attended by physician-staffed EMS. There were no differences in baseline characteristics in the propensity-score matched cohort consisting of 351 pairs. The return of spontaneous circulation (ROSC) was more often achieved in the physician-staffed EMS group (42.7% vs. 33.3%; P = 0.01). The prehospital survival rate was also higher in this group (34.1% vs. 19.2%; P <0.01). However, there were no significant differences in survival rate to discharge between cases treated by physician-staffed and paramedic-staffed EMS (9.7% vs. 7.0%; P = 0.22). OHCA patients attended by physician-staffed EMS were more likely to have ROSC and survive till hospital admission. However, better prehospital outcomes might not translate into improved in-hospital prognosis in these patients.

BackgroundAlthough prehospital cardiac arrest (CA) remains associated with poor long-term outcome, recent studies show an improvement in the survival rate after prehospital trauma associated CA (TCA). However, data on the...

Background: Lymphopenia and elevated cytokine levels suggest a role for the systemic immune response after cardiac arrest (CA). However, little is known about the phenotypes and interactions of immune cells after CA. This study aimed to investigate the immunological network after CA and identify cell states correlating with poor neurological outcomes. Methods: Peripheral mononuclear blood cells of 11 post-out-of-hospital CA patients and 3 healthy subjects were analyzed by single-cell RNA-sequencing (scRNA-seq), with validation by flow cytometry, bulk RNA-seq of sorted cell subsets, plasma levels of cytokines, and the murine model of CA. Good and poor neurological outcomes at hospital discharge were defined by Cerebral Performance Category 1-2 and 3-5, respectively. Results: The scRNA-seq analysis of 96,179 cells revealed 6 major cell lineages with several subclusters. At 6h post-CA, cells of patients with good outcomes co-clustered with healthy subjects, while patients with poor outcomes formed distinct transcriptomic clusters. This distinction was lost by 48h post-CA. At 6h post-CA, we identified pro-inflammatory and hypoxia-responsive Tim-3 + NK cell and Nectin-2 + monocyte cell states specific to poor outcomes. In a validation cohort of post-CA patients, Tim-3 + NK cells and Nectin-2 + monocyte cell states were validated by flow cytometry. Bulk RNA-seq analysis of these sorted cells reproduced the transcriptomic profile determined by scRNA-seq. Interactome analysis identified NK cell-monocyte axes in poor outcomes, including IFNG-IFNGR2. Measurement of plasma cytokine levels revealed increased IFNγ levels at 6h post-CA that were associated with poor outcomes, but both poor and good outcomes had similarIFNγ levels by 48h. A murine model of CA demonstrated that IFNγ drives poor outcomes and mortality after CA. Conclusions: In clinical CA, transcriptomic analysis at single-cell resolution revealed hyperacute cell states of NK cells and monocytes associated with poor neurological outcomes. These hyperacute cell states interact by IFNγ-IFNγR2 axis, which is pathogenic in the murine model of CA. The immunophenotypes that distinguish patients with poor or good neurological outcomes are present at 6h but are no longer detectable by 48h post-CA.

IntroductionSeveral methods have been proposed to evaluate neurological outcome in out-of-hospital cardiac arrest (OHCA) patients. Blood lactate has been recognized as a reliable prognostic marker for trauma, sepsis, or cardiac arrest. The objective of this study was to examine the association between initial lactate level or lactate clearance and neurologic outcome in OHCA survivors who were treated with therapeutic hypothermia.MethodsThis retrospective cohort study included patients who underwent protocol-based 24-hour therapeutic hypothermia after OHCA between January 2010 and March 2012. Serum lactate levels were measured at the start of therapy (0 hours), and after 6 hours, 12 hours, 24 hours, 48 hours and 72 hours. The 6 hour and 12 hour lactate clearance were calculated afterwards. Patients’ neurologic outcome was assessed at one month after cardiac arrest; good neurological outcome was defined as Cerebral Performance Category one or two. The primary outcome was an association between initial lactate level and good neurologic outcome. The secondary outcome was an association between lactate clearance and good neurologic outcome in patients with initial lactate level >2.5 mmol/l.ResultsOut of the 76 patients enrolled, 34 (44.7%) had a good neurologic outcome. The initial lactate level showed no significant difference between good and poor neurologic outcome groups (6.07 ±4 .09 mmol/L vs 7.13 ± 3.99 mmol/L, P = 0.42), However, lactate levels at 6 hours, 12 hours, 24 hours, and 48 hours in the good neurologic outcome group were lower than in the poor neurologic outcome group (3.81 ± 2.81 vs 6.00 ± 3.22 P <0.01, 2.95 ± 2.07 vs 5.00 ± 3.49 P <0.01, 2.17 ± 1.24 vs 3.86 ± 3.92 P <0.01, 1.57 ± 1.02 vs 2.21 ± 1.35 P = 0.03, respectively). The secondary analysis showed that the 6-hour and 12-hour lactate clearance was higher for good neurologic outcome patients (35.3 ± 34.6% vs 6.89 ± 47.4% P = 0.01, 54.5 ± 23.7% vs 25.6 ± 43.7% P <0.01, respectively). After adjusting for potential confounding variables, the 12-hour lactate clearance still showed a statistically significant difference (P = 0.02).ConclusionThe lactate clearance rate, and not the initial lactate level, was associated with neurological outcome in OHCA patients after therapeutic hypothermia.

Cerebral oximetry – The holy grail of non-invasive cerebral perfusion monitoring in cardiac arrest or just a false dawn?

BackgroundWe investigated the relationship between neurological outcomes and duration from cardiac arrest (CA) to the initiation of extracorporeal membrane oxygenation (ECMO) (CA-to-ECMO) in patients with out-of-hospital cardiac arrest (OHCA) treated with extracorporeal cardiopulmonary resuscitation (ECPR) and determined the ideal time at which ECPR should be performed.MethodsDuring the time period in which this study was conducted, 3451 patients experienced OHCA. This study finally included 79 patients aged 18 years or older whose OHCA had been witnessed and who underwent ECPR in the emergency room between January 2011 and December 2015. Our primary endpoint was survival to hospital discharge with good neurological outcomes (a cerebral performance category of 1 or 2).ResultsOf the 79 patients included, 11 had good neurological outcomes. The median duration from CA-to-ECMO was significantly shorter in the good neurological outcome group (33 min, interquartile range [IQR], 27–50 vs. 46 min, IQR, 42–56: p = 0.03). After controlling for potential confounders, we found that the adjusted odds ratio of CA-to-ECMO time for a good neurological outcome was 0.92 (95% confidence interval: 0.87–0.98, p = 0.007). The area under the receiver operating characteristic curve of CA-to-ECMO for predicting a good neurological outcome was 0.71, and the optimal CA-to-ECMO cutoff time was 40 min. The dynamic probability of survival with good neurological outcomes based on CA-to-ECMO time showed that the survival rate with good neurological outcome decreased abruptly from over 30% to approximately 15% when the CA-to-ECMO time exceeded 40 min.DiscussionIn this study, CA-to-ECMO time was significantly shorter among patients with good neurological outcomes, and significantly associated with good neurological outcomes at hospital discharge. In addition, the probability of survival with good neurological outcome decreased when the CA-to-ECMO time exceeded 40 minutes. The indication for ECPR for patients with OHCA should include several factors. However, the duration of CPR before the initiation of ECMO is a key factor and an independent factor for good neurological outcomes in patients with OHCA treated with ECPR. Therefore, the upper limit of CA-to-ECMO time should be inevitably included in the indication for ECPR for patients with OHCA. In the present study, there was a large difference in the rate of survival to hospital discharge with good neurological outcome between the patients with a CA-to-ECMO time within 40 minutes and those whose time was over 40 minutes. Based on the present study, the time limit of the duration of CPR before the initiation of ECMO might be around 40 minutes. We should consider ECPR in patients with OHCA if they are relatively young, have a witness and no terminal disease, and the initiation of ECMO is presumed to be within this time period.ConclusionsThe duration from CA-to-ECMO was significantly associated with good neurological outcomes. The indication for patients with OHCA should include a criterion for the ideal time to initiate ECPR.

Amplitude-spectral area and chest compression release velocity independently predict hospital discharge and good neurological outcome in ventricular fibrillation out-of-hospital cardiac arrest

Testosterone related good neurologic outcome on the patients with return of spontaneous circulation after cardiac arrest: A prospective cohort study

Background: Near infrared spectroscopy is a noninvasive method for assessing regional tissue oxygenation (StO2), a parameter influenced by microvascular perfusion. Normal StO2 values recorded from the thenar eminance are 87% ± 6%. In critically ill patients, low StO2 levels (&lt;70%) have been associated with a poor prognosis. We evaluated the prognostic significance of StO2 in patients undergoing therapeutic hypothermia (TH) after cardiac arrest (CA). Hypothesis: After resuscitation from CA, an initial StO2 ≥70%, or an initial StO2 &lt;70% followed by an upward trend, is associated with a good neurologic outcome. Methods: We conducted a retrospective analysis of CA patients who underwent TH between August, 2005 and June, 2013. StO2 levels at the thenar eminence were collected at the onset and hourly during TH. Neurological outcome was assessed by the Cerebral Performance Category (CPC) at hospital discharge. Good outcome was defined as survival to hospital discharge with a CPC ≤2. Univariate and multivariate analyses were performed. Results: Among 160 patients, 18% (n=29) survived with a CPC ≤2. Survival with a CPC ≤2 was associated with witnessed CA (p=0.04; OR 11.6; 95% CI 1.1-118.0), shockable rhythm (p=0.02; OR 3.4; 95% CI 1.2-9.3), time to return of spontaneous circulation (ROSC) ≤15 minutes (p=0.02; OR 4.5; 95% CI 1.2-16.6) and age &lt;65 (p=0.001; OR 7.6; 95% CI 2.3-25.5). However, an initial StO2 ≥70% was not associated with a CPC ≤2 (P=0.7; OR 0.82; 95% CI 0.29-2.2). For patients with an initial St02 &lt;70%, there was no difference in outcome between those with an upward trend vs downward trend in St02 (p=0.98). Conclusions: Similar to previous trials documenting the value of TH witnessed CA, shockable rhythm, short time to ROSC, and younger age were associated with a good neurologic outcome. StO2 levels recorded from the thenar eminence were not associated with neurologic outcome. These StO2 levels are influenced by regional perfusion and tissue oxygenation but may not reflect cerebral microvascular perfusion. Identifying alternative technologies to assess cerebral microvascular perfusion may help determine patients for whom a good neurologic outcome can be predicted.

OBJECTIVETo test the effect of a physician staffed advanced cardiac life support (ALS) system on patient outcome following out-of-hospital cardiac arrest.DESIGNObservational study.SETTINGTwo tier basic life support (BLS) and physician staffed...

The association between post resuscitation hemoglobin level and survival with good neurological outcome following Out Of Hospital cardiac arrest

Muscle mass depletion is associated with unfavorable outcomes in many diseases. However, its relationship with cardiac arrest outcomes has not been explored. This retrospective single-center study determined the relationship between muscle mass depletion and the neurological outcomes of patients with out-of-hospital cardiac arrest (OHCA) by measuring muscle mass at various locations. Adult patients with OHCA, who were treated with target temperature management, and who underwent abdominal or chest computed tomography (CT) within 3 months of the cardiac arrest were included. Skeletal muscle index (SMI) was measured at the third lumbar vertebra (L3) level, psoas muscle, fourth thoracic vertebra (T4) level, and pectoralis muscle. The Youden index was used to determine a low SMI based on sex-specific cutoff values. The outcome variables were "good neurological outcome" and "survival" at hospital discharge. Multivariable analyses revealed that patients with low T4 SMI level were significantly associated with good neurological outcomes at hospital discharge (odds ratio = 0.26, 95% confidence interval: 0.07-0.88, p = 0.036). However, no significant differences were observed between good neurological outcomes and low SMI at the L3 level and psoas and pectoralis muscles; SMIs were not associated with survival at hospital discharge. T4 level SMI depletion was inversely associated with good neurological outcomes in patients with OHCA. Thoracic muscle depletion may be crucial for predicting the neurological outcomes in patients with OHCA and further investigation in larger prospective study is warranted.

The early prediction of neurological outcomes is useful for out-of-hospital cardiac arrest (OHCA). The initial pH was associated with neurological outcomes, but the values varied among the studies. Patients admitted to our division with OHCA of cardiac origin between January 2015 and December 2022 were retrospectively examined (N = 199). A good neurological outcome was defined as a Glasgow-Pittsburgh cerebral performance category (CPC) of 1-2 at discharge. Patients were divided according to the achievement of recovery of spontaneous circulation (ROSC) on hospital arrival, and the efficacy of pH in predicting good neurological outcomes was compared. In patients with ROSC on hospital arrival (N = 100), the initial pH values for good and poor neurological outcomes were 7.26 ± 0.14 and 7.09 ± 0.18, respectively (p < 0.001). In patients without ROSC on hospital arrival (N = 99), the initial pH values for good and poor neurological outcomes were 7.06 ± 0.23 and 6.92 ± 0.15, respectively (p = 0.007). The pH associated with good neurological outcome was much lower in patients without ROSC than in those with ROSC on hospital arrival (P = 0.003). A higher initial pH is associated with good neurological outcomes in patients with OHCA. However, the pH for a good or poor neurological outcome depends on the ROSC status on hospital arrival.

Comparison of team-focused CPR vs standard CPR in resuscitation from out-of-hospital cardiac arrest: Results from a statewide quality improvement initiative