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In mechanically ventilated (MV) cardiac arrest (CA) survivors admitted to the intensive care unit (ICU) avoidance of hypoxia is considered crucial. However, avoidance of hyperoxia may also be important. A conservative approach to oxygen therapy may reduce exposure to both.We evaluated the introduction of conservative oxygen therapy (target SpO2 88-92% using the lowest FiO2) during MV for resuscitated CA patients admitted to the ICU.We studied 912 arterial blood gas (ABG) datasets: 448 ABGs from 50 'conventional' and 464 ABGs from 50 'conservative' oxygen therapy patients. Compared to the conventional group, conservative group patients had significantly lower PaO2 values and FiO2 exposure (p0.001, respectively); more received MV in a spontaneous ventilation mode (18% vs 2%; p=0.001) and more were exposed to a FiO2 of 0.21 (19 vs 0 patients, p=0.001). Additionally, according to mean PaO2, more conservative group patients were classified as normoxaemic (36 vs 16 patients, p0.01) and fewer as hyperoxaemic (14 vs 33 patients, p0.01). Finally, ICU length of stay was significantly shorter for conservative group patients (p=0.04). There was no difference in the proportion of survivors discharged from hospital with good neurological outcome (14/23 vs 12/22 patients, p=0.67).Our findings provide preliminary support for the feasibility and physiological safety of conservative oxygen therapy in patients admitted to ICU for MV support after cardiac arrest (Trial registration, NCT01684124).

Summary Background Rapid Response Team (RRT) calls can often occur within 24h of hospital admission to a general ward. We seek to determine whether it is possible to identify these patients before there is a significant clinical deterioration. Methods Retrospective case–controlled study comparing patient characteristics, vital signs, and hospital outcomes in patients triggering RRT activation within 24h of ED admission (cases) with matched ED admissions not receiving a RRT call (controls). Results Over 12 months, there were 154 early RRT calls. Compared with controls, cases had a higher heart rate (HR) at triage (92 vs. 84beats/min; p =0.008); after 3h in the ED (91 vs. 80beats/min; p =0.0007); and at ED discharge (91 vs. 81beats/min; p =0.0005). Respiratory rate (RR) was also higher at triage (21.2 vs. 19.2breaths/min; p =0.001). On multiple variable analysis, RR at triage and HR before ward transfer predicted early RRT activation: OR 1.07 [95% CI 1.02–1.12] for each 1breath/min increase in RR; and 1.02 [95% CI 1.002–1.030] for each beat/minute increase in HR, respectively. Study patients required transfer to the intensive care in approximately 20% of cases and also had a greater mortality: (21% vs. 6%; OR 4.65 [95% CI 1.86–11.65]; p =0.0003) compared with controls. Conclusions Patients that trigger RRT calls within 24h of admission have a fourfold increase in risk of in-hospital mortality. Such patients may be identified by greater tachycardia and tachypnoea in the ED.

a b s t r a c t Background: In hospital cardiac arrests (CA) treated with cardio-pulmonary resuscitation (CPR) outside of the intensive care unit (ICU) have poor outcomes. Most are preceded by deranged vital signs. There are, however, limited studies assessing antecedents to CAs inside the ICU. Objectives: To study the antecedents to, and characteristics of CAs in ICU. Study population: We prospectively identified CA cases that occurred inside our ICU between January 2010 and July 2012. Controls were obtained by sequentially matching ICU patients based on APACHE III diagnosis, APACHE III score, age, gender and length of stay in ICU. Results: Thirty-six patients had a CA during the study period (6.28/1000 admissions). In the 12 h prior to CA, index patients had higher maximum (22 breaths/min vs. 18 breaths/min, p = 0.001) and minimum respiratory rates (16 breaths/min vs. 12 breaths/min, p = 0.031), a lower median mean arterial pressure (65 mmHg vs. 70 mmHg, p = 0.029) and systolic blood pressure (97 mmHg vs. 106 mmHg, p = 0.033), a higher central venous pressure (14 cm H2O vs. 11 cm H2O, p = 0.008) and a lower bicarbonate level (20.5 mmol vs. 26 mmol, p = 0.018) compared to controls. CA patients also had a higher maximum dose of noradrenaline (norepinephrine) (17.5 mcg/min vs. 8.0 mcg/min, p = 0.052) but there was no difference in any other levels of intensive care support. Two-thirds of CA's occurred within the first 48 h of ICU admis- sion. The initial monitored rhythm was non-shock responsive (pulseless electrical activity, bradycardia or asystole) in 26/36 (72%). Return of spontaneous circulation was achieved in 29/36 (80.6%) patients, with 16/36 (44.4%) surviving to hospital discharge. Conclusions: In the period leading up to the CA inside ICU, there were signs of physiological instability and the need for higher doses of noradrenaline. Return of spontaneous circulation was achieved in 80%. However, in-hospital mortality was greater than 50%. © 2013 Elsevier Ireland Ltd. All rights reserved.