Base excess and lactate as prognostic indicators for patients admitted to intensive care

Objective: To examine whether values of arterial base excess or lactate taken on admission to a general intensive care unit indicate prognosis, and whether this can be used as a screening tool for future intensive care admissions. Design: Observational study. Setting: University teaching hospital general adult intensive care unit. Patients: 148 consecutive patients admitted to the intensive care unit. Interventions: Arterial blood samples were obtained on admission to the intensive care unit and 24 h following admission. Measurements and results: Arterial base excess and lactate concentrations were measured from the blood samples. Both base excess and arterial lactate samples on admission have good prognostic abilities (area under the curve on receiver operator characteristic analysis of 0.73, 0.78, respectively). The value of base excess on admission with the best predictive ability was a base excess more negative than –4 mmol/l, and the corresponding value for lactate was greater than 1.5 mmol/l. The combination of these two markers on admission to the intensive care unit led to a sensitivity of 80.3 % and a specificity of 58.7 % for mortality. The achievement of this combination was associated with an increased mortality (50.6 % vs. 15 %, p < 0.0001), older age (70 vs. 61.5 years, p < 0.05), a greater requirement for inotropic support (30.9 % vs. 4.5 %, p < 0.0001) and higher organ failure scores both on admission and for the subsequent 24 h. Conclusions: Both base excess and lactate, or the combination of the two, can be used to predict outcome in patients admitted to the intensive care unit. These variables could be utilized to identify patients who have a high risk for mortality and thus who should be admitted to the intensive care unit. Received: 18 April 2000 Final revision received: 15 May 2000 Accepted: 15 May 2000     

Extracorporeal life support associated with hypothermia and normoxemia in refractory cardiac arrest

Aim

We describe a 1-year experience with extracorporeal cardiopulmonary resuscitation (ECPR) for in-hospital (IHCA) and out-of-hospital cardiac arrest (OHCA) associated with intra-arrest hypothermia and normoxemia.

Methods

Since January 1st 2012, ECPR has been applied in our hospital to all patients less than 65 years of age and without major co-morbidities who develop refractory cardiac arrest (CA) with bystander CPR. Over a 1-year period of observation, we recorded 28-day survival with intact neurological outcome and the rate of organ donation.

Results

During the observational period, 24 patients were treated with ECPR, with a median age of 48 years. Ten patients had IHCA. Acute coronary syndrome and/or major arrhythmias were the main cause of arrest. Intra-arrest cooling was used in 17 patients; temperature on ECMO initiation in these patients was 32.9 °C [32–34]. The time from collapse to ECPR was 58 min [45–70] and was shorter in survivors than in non-survivors (41 min [39–58] vs. 60 min [55–77], p = 0.059). Non-survivors were more likely to have coagulopathy and received more blood transfusions. Six patients (25%) survived with good neurological outcome at day 28. Four patients with irreversible brain damage had organ function suitable for donation.

Conclusion

ECPR provided satisfactory survival rates with good neurologic recovery in refractory CA for both IHCA and OHCA. ECMO may help rapidly stabilise systemic haemodynamic status and restore organ function.     

Improving outcome after out-of-hospital cardiac arrest by strengthening weak links of the local Chain of Survival; quality of advanced life support and post-resuscitation care

Background

Survival after out-of-hospital cardiac arrest (OHCA) depends on a well functioning Chain of Survival. We wanted to assess if targeted attempts to strengthen the weak links of our local chain; quality of advanced life support (ALS) and post-resuscitation care, would improve outcome.

Materials and methods

Utstein data from all OHCAs in Oslo during three distinct 2-year time periods 1996-1998, 2001-2003 and 2004-2005 were collected. Before the second period the local ALS guidelines changed with increased focus on good quality chest compressions with minimal pauses, while standardized post-resuscitation care including goal directed therapy with therapeutic hypothermia and percutaneous coronary intervention was added in the third period. Additional a priori sub-group analyses of arrests with cardiac aetiology as well as bystander witnessed ventricular fibrillation/tachycardia (VF/VT) arrests with cardiac aetiology were performed.

Results

ALS was attempted in 454, 449, and 417 patients with OHCA in the first, second and last time period, respectively. From the first to the third period VF/VT arrests declined (40% vs. 33%, p = 0.039) and fewer arrests were witnessed (80% vs. 72%, p = 0.022) and response intervals increased (7 ± 4 to 9 ± 4 min, p < 0.001). Overall survival increased from 7% (first period) to 13% (last period), p = 0.002, and survival in the sub-group of bystander witnessed VF/VT arrests with cardiac aetiology increased from 15% (first period) to 35% (last period), p = 0.001.

Conclusions

Survival after OHCA was increased after improving weak links of our local Chain of Survival, quality of ALS and post-resuscitation care.     

The incidence and significance of bacteremia in out of hospital cardiac arrest

Background

The most common etiology of cardiac arrest is presumed of myocardial origin. Recent retrospective studies indicate that preexisting pneumonia, a form of sepsis, is frequent in patients who decompensate with abrupt cardiac arrest without preceding signs of septic shock, respiratory failure or severe metabolic disorders shortly after hospitalization. The contribution of pre-existing infection on pre and post cardiac arrest events remains unknown and has not been studied in a prospective fashion. We sought to examine the incidence of pre-existing infection in out-of hospital cardiac arrest (OHCA) and assess characteristics associated with bacteremia, the goal standard for presence of infection.

Methods and results

We prospectively observed 250 OHCA adult patients who presented to the Emergency Department (ED) between 2007 and 2009 to an urban academic teaching institution. Bacteremia was defined as one positive blood culture with non-skin flora bacteria or two positive blood cultures with skin flora bacteria. 77 met pre-defined exclusion criteria. Of the 173 OHCA adults, 65 (38%) were found to be bacteremic with asystole and PEA as the most common presenting rhythms. Mortality in the ED was significantly higher in bacteremic OHCA (75.4%) compared to non-bacteremic OHCA (60.2%, p < 0.05). After adjustment for potential confounders, predictive factors associated with bacteremic OHCA were lower initial arterial pH, higher lactate, WBC, BUN and creatinine.

Conclusions

Over one-third of OHCA adults were bacteremic upon presentation. These patients have greater hemodynamic instability and significantly increased short-term mortality. Further studies are warranted to address the epidemiology of infection as possible cause of cardiac arrest.     

Conversion to shockable rhythms during resuscitation and survival for out-of hospital cardiac arrest

Background

In out of hospital cardiac arrest (OHCA), the prognostic influence of conversion to shockable rhythms during resuscitation for initially non-shockable rhythms remains unknown. This study aimed to assess the relationship between initial and subsequent shockable rhythm and post-arrest survival and neurological outcomes after OHCA.