Haemodynamic variables and functional outcome in hypothermic patients following out-of-hospital cardiac arrest

Aim of the study

To evaluate the association between haemodynamic variables during the first 24 h after intensive care unit (ICU) admission and neurological outcome in out-of-hospital cardiac arrest (OHCA) victims undergoing therapeutic hypothermia.

Methods

In a multi-disciplinary ICU, records were reviewed for comatose OHCA patients undergoing therapeutic hypothermia. The hourly variable time integral of haemodynamic variables during the first 24 h after admission was calculated. Neurologic outcome was assessed at day 28 and graded as favourable or adverse based on the Cerebral Performance Category of 1–2 and 3–5. Bi- and multivariate regression models adjusted for confounding variables were used to evaluate the association between haemodynamic variables and functional outcome.

Results

67/134 patients (50%) were classified as having favourable outcome. Patients with adverse outcome had a higher mean heart rate (73 [62–86] vs. 66 [60–78] bpm; p = 0.04) and received noradrenaline more frequently (n = 17 [25.4%] vs. n = 9 [6%]; p = 0.02) and at a higher dosage (128 [56–1004] vs. 13 [2–162] μg h⁻¹; p = 0.03) than patients with favourable outcome. The mean perfusion pressure (mean arterial blood pressure minus central venous blood pressure) (OR = 1.001, 95% CI  = 1–1.003; p = 0.04) and cardiac index time integral (OR = 1.055, 95% CI = 1.003–1.109; p = 0.04) were independently associated with adverse outcome at day 28.

Conclusion

Mean perfusion pressure and cardiac index during the first 24 h after ICU admission were weakly associated with neurological outcome in an OHCA population undergoing therapeutic hypothermia. Further studies need to elucidate whether norepinephrine-induced increases in perfusion pressure and cardiac index may contribute to adverse neurologic outcome following OHCA.     

Neuron specific enolase and S-100B as predictors of outcome after cardiac arrest and induced hypothermia

Aim

To assess the prognostic value of repetitive serum samples of neuron specific enolase (NSE) and S-100B in cardiac arrest patients treated with hypothermia.

Methods

In a three-centre study, comatose patients after cardiac arrest were treated with hypothermia at 33 °C for 24 h, regardless of cause or the initial rhythm. Serum samples were collected at 2, 24, 48 and 72 h after the arrest and analysed for NSE and S-100B in a non-blinded way. The cerebral performance categories scale (CPC) was used as the outcome measure; a best CPC of 1–2 during 6 months was regarded as a good outcome, a best CPC of 3–5 a poor outcome.

Results

One centre was omitted in the NSE analysis due to missing 24 and 48 h samples. Two partially overlapping groups were studied, the NSE group (n = 102) and the S-100B group (n = 107). NSE at 48 h >28 μg/l (specificity 100%, sensitivity 67%) and S-100B >0.51 μg/l at 24 h (specificity 96%, sensitivity 62%) correlated with a poor outcome, and so did a rise in NSE of >2 μg/l between 24 and 48 h (odds ratio 9.8, CI 3.5–27.7). A majority of missing samples (n = 123) were from the 2 h sampling time (n = 56) due to referral from other hospitals or inter-hospital transfer.

Conclusion

NSE was a better marker than S-100B for predicting outcome after cardiac arrest and induced hypothermia. NSE above 28 μg/l at 48 h and a rise in NSE of more than 2 μg/l between 24 and 48 h were markers for a poor outcome.     

C-reactive protein levels after cardiac arrest in patients treated with therapeutic hypothermia

Aim

Prognostication of outcome after cardiac arrest (CA) is challenging. We assessed the prognostic value of daily blood levels of C-reactive protein (CRP), a cheap and widely available inflammatory biomarker, after CA.

Methods

We reviewed the data of all patients admitted to our intensive care unit (ICU) after CA between January 2009 and December 2011 and who survived for at least 24 h. We collected demographic data, CA characteristics (initial rhythm; location of arrest; time to return of spontaneous circulation [ROSC]), occurrence of infection, ICU survival and neurological outcome at three months (good = cerebral performance category [CPC] 1–2; poor = CPC 3–5). CRP levels were measured daily from admission to day 3.

Results

A total of 130 patients were admitted after successful resuscitation from CA and survived more than 24 h; 76 patients (58%) developed an infection and overall mortality was 56%. CRP levels increased from admission to day 3. CRP levels were higher in in-hospital than in out-of-hospital CA, especially on admission and day 1 (44.1 vs. 2.1 mg L⁻¹ and 74.5 vs. 29.5 mg L⁻¹, respectively; p < 0.001), and in patients with non-shockable than in those with shockable rhythms. In a logistic regression model, high CRP levels on admission were independently associated with poor neurological outcome at 3 months.

Conclusion

CRP levels increase in the days following successful resuscitation of CA. Higher CRP levels in patients with in-hospital CA, non-shockable rhythms and infection, suggest a greater inflammatory response in these patients. High CRP levels on admission may identify patients at high-risk of poor outcome and could be a target for future therapies.     

Short-term changes in median nerve neural tension after a suboccipital muscle inhibition technique in subjects with cervical whiplash: a randomised controlled trial

Objectives

To assess the immediate effect of a suboccipital muscle inhibition (SMI) technique on: (a) neck pain, (b) elbow extension range of motion during the upper limb neurodynamic test of the median nerve (ULNT-1), and (c) grip strength in subjects with cervical whiplash; and determine the relationships between key variables.

Design

Randomised, single-blind, controlled clinical trial.

Setting

Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, Spain.

Participants

Forty subjects {mean age 34 years [standard deviation (SD) 3.6]} with Grade I or II cervical whiplash and a positive response to the ULNT-1 were recruited and distributed into two study groups: intervention group (IG) (n = 20) and control group (CG) (n = 20).

Interventions

The IG underwent the SMI technique for 4 minutes and the CG received a sham (placebo) intervention. Measures were collected immediately after the intervention.

Main outcome measures

The primary outcome was elbow range of motion during the ULNT-1, measured with a goniometer. The secondary outcomes were self-perceived neck pain (visual analogue scale) and free-pain grip strength, measured with a digital dynamometer.

Results

The mean baseline elbow range of motion was 116.0° (SD 10.2) for the CG and 130.1° (SD 7.8) for the IG. The within-group comparison found a significant difference in elbow range of motion for the IG [mean difference −15.4°, 95% confidence interval (CI) −20.1 to −10.6; P = 0.01], but not for the CG (mean difference −4.9°, 95% CI −11.8 to 2.0; P = 0.15). In the between-group comparison, the difference in elbow range of motion was significant (mean difference −10.5°, 95% CI −18.6 to −2.3; P = 0.013), but the differences in grip strength (P = 0.06) and neck pain (P = 0.38) were not significant.

Conclusion

The SMI technique has an immediate positive effect on elbow extension in the ULNT-1. No immediate effects on self-perceived cervical pain or grip strength were observed.     

Factors affecting survival from avalanche burial—A randomised prospective porcine pilot study

Background and aim

The majority of avalanche victims who sustain complete burial die within 35 min due to asphyxia and injuries. After 35 min, survival is possible only in the presence of a patent airway, and an accompanying air pocket around the face may improve survival. At this stage hypothermia is assumed to be an important factor for survival because rapid cooling decreases oxygen consumption; if deep hypothermia develops before cardiac arrest, hypothermia may be protective and prolong the time that cardiac arrest can be survived. The aim of the study was to investigate the combined effects of hypoxia, hypercapnia and hypothermia in a porcine model of avalanche burial.

Methods

Eight piglets were anaesthetised, intubated and buried under snow, randomly assigned to an air pocket (n = 5) or ambient air (n = 3) group.

Results

Mean cooling rates in the first 10 min of burial were −19.7 ± 4.7 °C h⁻¹ in the air pocket group and −13.0 ± 4.4 °C h⁻¹ in the ambient air group (P = 0.095); overall cooling rates between baseline and asystole were −4.7 ± 1.4 °C h⁻¹ and −4.6 ± 0.2 °C h⁻¹ (P = 0.855), respectively. In the air pocket group cardiac output (P = 0.002), arterial oxygen partial pressure (P = 0.001), arterial pH (P = 0.002) and time to asystole (P = 0.025) were lower, while arterial carbon dioxide partial pressure (P = 0.007) and serum potassium (P = 0.042) were higher compared to the ambient air group.

Conclusion

Our results demonstrate that hypothermia may develop in the early phase of avalanche burial and severe asphyxia may occur even in the presence of an air pocket.     

Can early serum levels of S100B protein predict the prognosis of patients with out-of-hospital cardiac arrest?

Objective

This study aims to know if the level of S100B protein at the initiation of cardiopulmonary resuscitation (CPR) and immediately after return of spontaneous circulation (ROSC) can predict clinical outcome.

Materials and methods

A prospective observational study from December 2004 to October 2006 was conducted in an urban tertiary hospital emergency department. Clinical demographics for out-of-hospital cardiac arrest patients were collected based on the Utstein style. Outcomes collected included ROSC for 20 min, survival to admission, survival and Glasgow Outcome Scale (GOS) at 1 month. S100B protein was measured twice before starting CPR (first S100B) and immediately after ROSC (second S100B). We investigated the association between S100B protein levels and clinical outcomes using a multivariate logistic regression model.

Results

A total of 151 patients were included (age: 60.2 ± 16.8 years, male: 64.2%). Of these, 60 (39.7%) had ROSC and 46 (30.5%) survived to admission. After 1 month, 12 (8.0%) survived and only three patients showed good GOS (≥4 points). The S100B levels were not different for ROSC, survival to admission and 1-month survival between survivors and non-survivors (p > 0.05, first and second S100 B level). For the witnessed out-of-hospital cardiac arrest (OHCA) group (N = 87), only the first S100B (1.22 ± 0.85 μg l⁻¹ vs. 3.91 ± 4.25 μg l⁻¹, p < 0.001) showed significant difference for 1-month survival between survivors and non-survivors. The first S100B showed significant association with survival to emergency department (ED) but not 1-month survival (adjusted odds ratio (OR) = 0.905, 95% confidence interval = 0.821-0.998).

Conclusion

Higher levels of S100B at start of CPR were significantly associated with lower survival to admission, and not for 1-month survival.     

Effects of intracerebroventricular application of insulin-like growth factor 1 and its N-terminal tripeptide on cerebral recovery following cardiac arrest in rats

Background

Following global cerebral ischaemia due to cardiac arrest (CA), selective neuronal vulnerability and delayed neuronal death with distinct signs of apoptosis could be observed in certain areas of the brain. Growth hormones like the insulin-like growth factor 1 (IGF-1) and the bioactive N-terminal tripeptide of IGF-1, glycine–proline–glutamate (GPE), exhibit strong protective properties in focal ischaemia in vivo and in vitro. To examine these promising effects on neuronal survival and cerebral recovery after experimental cardiopulmonary resuscitation, the most vulnerable hippocampal CA-1 sector was investigated.

Methods

After 6 min of CA, 54 male Wistar rats were resuscitated and were randomly assigned to 3 groups (IGF-1, GPE vs. placebo; n = 6 per group) and 3 different reperfusion periods. Intracerebroventricular application of IGF-1 (1.25 μg h⁻¹), GPE (50 ng h⁻¹) and placebo was performed using osmotic minipumps up to day 7 following reperfusion. After 3, 7 and 14 days, coronal brain sections were analysed by counting Nissl-positive (i.e. viable) neurons and TUNEL-positive (i.e. apoptotic) cells. All experiments were performed in a randomised and blinded setting.

Results

In all groups in the hippocampal CA-1 sector typical delayed neurodegeneration from day 3 to day 14 after CA could be found. No significant increase of the number of Nissl-positive neurons after IGF-1-treatment (p = 0.18) as well as after GPE-treatment (p = 0.14) could be observed. The number of TUNEL-positive cells could not be reduced significantly in the IGF-1 group (p = 0.13), whereas GPE treatment revealed significant less TUNEL-positive cells (p = 0.02). This was primarily an effect in the early phase (day 3: p = 0.02) of reperfusion and was no more detectable 7 days (p = 0.69) and 14 days after ROSC (p = 0.30).

Conclusion

Despite the well known neuroprotective properties of IGF-1 and GPE in ischaemic induced neuronal degeneration, this model could only reveal a short-term beneficial effect of GPE after experimental cardiac arrest in rats. (Institutional protocol number: 35-9185.81/43/00.)     

The effects of sleep on the relationship between brain injury severity and recovery of cognitive function: A prospective study

Background

Disturbed sleep pattern is a common symptom after head trauma and its prevalence in acute traumatic brain injury (TBI) is less discussed. Sleep has a profound impact on cognitive function recovery and the mediating effect of disturbed sleep on cognitive function recovery has not been examined after acute TBI.

Objectives

To identify the prevalence of disturbed sleep in mild, moderate, and severe acute TBI patients, and to determine the mediating effects of sleep on the relationship between brain injury severity and the recovery of cognitive function.

Design

A prospective study design.

Setting

Neurosurgical wards in a medical center in northern Taiwan.

Participants

Fifty-two acute TBI patients between the ages of 18 and 65 years who had received a diagnosis of TBI for the first time, and were admitted to the neurosurgical ward.

Method

The severity of brain injury was initially determined using the Glasgow Coma Scale. Each patient wore an actigraphy instrument on a non-paralytic or non-dominated limb for 7 consecutive days. A 7-day sleep diary was used to facilitate data analysis. Cognitive function was assessed on the first and seventh day after admission based on the Rancho Los Amigos Levels of Cognitive Functioning.

Results

The mild (n = 35), moderate (n = 7) and severe (n = 10) TBI patients exhibited poorer sleep efficiency, and longer total sleep time (TST) and waking time after sleep onset, compared with the normative values for the sleep-related variables (P < .05 for all). The severe and moderate TBI patients had longer daytime TST than the mild TBI patients (P < .001), and the severe TBI patients had longer 24-h TST than the mild TBI patients (P = .001). The relationship between the severity of brain injury and the recovery of cognition function was mediated by daytime TST (t = −2.65, P = .004).

Conclusions

Poor sleep efficiency, prolonged periods of daytime sleep, and a high prevalence of hypersomnia are common symptoms in acute TBI patients. The duration of daytime sleep mediates the relationship between the severity of brain injury and the recovery of cognition function.     

A multifaceted educational intervention to prevent delirium in older inpatients: A before and after study

Background

Systematically targeting modifiable risk factors for delirium may reduce its incidence. However, research interventions have not become part of routine clinical practice. Particular approaches to the education of clinical staff may improve their practice and patient outcomes.

Objectives

To evaluate the effectiveness of a multifaceted educational program in preventing delirium in hospitalised older patients and improving staff practice, knowledge and confidence.

Design

A before and after study.

Setting

A 22-bed general medical ward of a district hospital in Sydney, Australia.

Participants

Patients were aged 65 years and over and not delirious upon admission. Of 568 eligible patients, 129 were recruited pre-intervention (3 withdrew initial consent) and 129 patients post-intervention.

Methods

Prior to the intervention, in order to establish a baseline, patients were assessed early after admission and again at discharge. The intervention was a one-hour lecture on delirium focusing on prevention for medical and nursing staff followed by weekly interactive tutorials with delirium resource staff and ward modifications. Following the initial education session, data were gathered in a second group of medical ward patients at the same time-points to ascertain the effectiveness of the intervention. Pre and post-intervention data were analysed to determine change in staff objective knowledge and self-ratings of confidence and clinical practice in relation to delirium. The main outcome measures were incident delirium and change in staff practice, confidence and knowledge.

Results

The mean age of patients was 81. The pre and post-intervention groups were comparable, aside from greater co morbidity in the pre-intervention group (F(1, 253) = 9.20, p = 0.003). Post-intervention there was a significant reduction in incident delirium (19% vs. 10.1%, X² = 4.14, p = 0.042), and improved function on discharge (mean improvement 5.3 points, p < 0.001, SD 13.31, 95% CI −7.61 to −2.97). Staff objective knowledge of delirium improved post-intervention and their confidence assessing and managing delirious patients. Staff addressed more risk factors for delirium post-intervention (8.1 vs. 9.8, F(1, 253) = 73.44, p < 0.001).

Conclusions

A low-cost educational intervention reduced the incidence of delirium and improved function in older medical patients and staff knowledge and practice addressing risk factors for delirium. The program is readily transferable to other settings, but requires replication due to limitations of the before and after design.     

Blood ammonia and lactate levels on hospital arrival as a predictive biomarker in patients with out-of-hospital cardiac arrest

Introduction

No reliable predictor for the prognosis of out-of-hospital cardiac arrest (OHCA) on arrival at hospital has been identified so far. We speculate that ammonia and lactate may predict patient outcome.

Methods

This is a prospective observational study. Non-traumatic OHCA patients who gained sustained return of spontaneous circulation and were admitted to acute care unit were included. Blood ammonia and lactate levels were measured on arrival at hospital. The patients were classified into two groups: ‘favourable outcome’ group (Cerebral Performance Category CPC1-2 at 6-months’ follow-up) and ‘poor outcome’ group (CPC3-5). Basal characteristics obtained from the Utstein template and biomarker levels were compared between these two outcome groups. Independent predictors were selected from all candidates using logistic regression analysis.

Results

A total of 98 patients were included. Ammonia and lactate levels in the favourable outcome group (n = 10) were significantly lower than those in poor outcome group (n = 88) (p < 0.05, respectively). On receiver operating characteristic analysis, the optimal cut-off value for predicting favourable outcome was determined as 170 μg dl⁻¹ of ammonia and 12.0 mmol l⁻¹ of lactate (area under the curve; 0.714 and 0.735, respectively). Logistic regression analysis identified ammonia (≤170 μg dl⁻¹), therapeutic hypothermia and witnessed by emergency medical service personnel as independent predictors of favourable outcome. When both these biomarker levels were over threshold, positive predictive value (PPV) for poor outcome was calculated as 100%.

Conclusions

Blood ammonia and lactate levels on arrival are independent prognostic factors for OHCA. PPV with the combination of these biomarkers predicting poor outcome is high enough to be useful in clinical settings.     

Predicting outcome after severe traumatic brain injury using the serum S100B biomarker: Results using a single (24 h) time-point

Background and objectives

In recent years, biochemical markers have been employed to predict the outcome of patients with traumatic brain injury (TBI). In mild TBI, S100B has shown the most promise as a marker of outcome. The objective of this study in patients with severe TBI was to: show the range of serum S100B levels during the acute phase after trauma: determine if S100B has potential to discriminate favourable from unfavourable outcome in patients with similar brain injury severity scores and to establish an S100B ‘cut-off’ predictive for death.

Methods

All patients with severe TBI, admitted to this neurointensive care unit within 24 h of injury were eligible for inclusion in the study. One serum blood sample was obtained from each patient at the 24 h post-injury time-point. S100B levels were measured using enzyme-linked immunosorbent assay. Injuries were coded using an internationally recognised injury severity scoring system (ISS). Three-month follow-up was undertaken with outcome assessed using the Glasgow outcome score (GOS).

Results

One hundred patients were recruited. Serum S100B levels ranged from 0.08 to 12.62 μg L⁻¹ S100B levels were significantly higher in patients with a GOS of 1 (death) 2 and 3 (unfavourable outcome) compared with those with GOS 4 and 5 (good recovery). In this study a cut-off point of 0.53 μg L⁻¹ has sensitivity of >80% and specificity of 60% to predict unfavourable outcome and 49% to predict death.

Conclusion

In 100 patients studied with similar brain injury severity scores, serum S100B measured at the 24-h time-point after injury is significantly associated with outcome but a cut-off 0.53 μg L⁻¹ does not have good prognostic performance.     

A randomised control trial of prompt and feedback devices and their impact on quality of chest compressions—A simulation study

Aim

This study aims to compare the effect of three CPR prompt and feedback devices on quality of chest compressions amongst healthcare providers.

Methods

A single blinded, randomised controlled trial compared a pressure sensor/metronome device (CPREzy™), an accelerometer device (Phillips Q-CPR) and simple metronome on the quality of chest compressions on a manikin by trained rescuers. The primary outcome was compression depth. Secondary outcomes were compression rate, proportion of chest compressions with inadequate depth, incomplete release and user satisfaction.

Results

The pressure sensor device improved compression depth (37.24–43.64 mm, p = 0.02), the accelerometer device decreased chest compression depth (37.38–33.19 mm, p = 0.04) whilst the metronome had no effect (39.88 mm vs 40.64 mm, p = 0.802). Compression rate fell with all devices (pressure sensor device 114.68–98.84 min⁻¹, p = 0.001, accelerometer 112.04–102.92 min⁻¹, p = 0.072 and metronome 108.24 min⁻¹ vs 99.36 min⁻¹, p = 0.009). The pressure sensor feedback device reduced the proportion of compressions with inadequate depth (0.52 vs 0.24, p = 0.013) whilst the accelerometer device and metronome did not have a statistically significant effect. Incomplete release of compressions was common, but unaffected by the CPR feedback devices. Users preferred the accelerometer and metronome devices over the pressure sensor device. A post hoc study showed that de-activating the voice prompt on the accelerometer device prevented the deterioration in compression quality seen in the main study.

Conclusion

CPR feedback devices vary in their ability to improve performance. In this study the pressure sensor device improved compression depth, whilst the accelerometer device reduced it and metronome had no effect.     

Adrenaline for out-of-hospital cardiac arrest resuscitation: A systematic review and meta-analysis of randomized controlled trials

Introduction

The evidence for adrenaline in out-of-hospital cardiac arrest (OHCA) resuscitation is inconclusive. We systematically reviewed the efficacy of adrenaline for adult OHCA.

Methods

We searched in MEDLINE, EMBASE, and Cochrane Library from inception to July 2013 for randomized controlled trials (RCTs) evaluating standard dose adrenaline (SDA) to placebo, high dose adrenaline (HDA), or vasopressin (alone or combination) in adult OHCA patients. Meta-analyses were performed using random effects modeling. Subgroup analyses were performed stratified by cardiac rhythm and by number of drug doses. The primary outcome was survival to discharge and the secondary outcomes were return of spontaneous circulation (ROSC), survival to admission, and neurological outcome.

Results

Fourteen RCTs (n = 12,246) met inclusion criteria: one compared SDA to placebo (n = 534), six compared SDA to HDA (n = 6174), six compared SDA to an adrenaline/vasopressin combination (n = 5202), and one compared SDA to vasopressin alone (n = 336). There was no survival to discharge or neurological outcome differences in any comparison group, including subgroup analyses. SDA showed improved ROSC (RR 2.80, 95%CI 1.78–4.41, p < 0.001) and survival to admission (RR 1.95, 95%CI 1.34–2.84, p < 0.001) compared to placebo. SDA showed decreased ROSC (RR 0.85, 95%CI 0.75–0.97, p = 0.02; I² = 48%) and survival to admission (RR 0.87, 95%CI 0.76–1.00, p = 0.049; I² = 34%) compared to HDA. There were no differences in outcomes between SDA and vasopressin alone or in combination with adrenaline.

Conclusions

There was no benefit of adrenaline in survival to discharge or neurological outcomes. There were improved rates of survival to admission and ROSC with SDA over placebo and HDA over SDA.     

Markers of intestinal injury are associated with endotoxemia in successfully resuscitated patients

Aims

Gut dysfunction is suspected to play a major role in the pathophysiology of post-resuscitation disease through an increase in intestinal permeability and endotoxin release. However this dysfunction often remains occult and is poorly investigated. The aim of this pilot study was to explore intestinal failure biomarkers in post-cardiac arrest patients and to correlate them with endotoxemia.

Methods

Following resuscitation after cardiac arrest, 21 patients were prospectively studied. Urinary intestinal fatty acid-binding protein (IFABP), which marks intestinal permeability, plasma citrulline, which reflects the functional enterocyte mass, and whole blood endotoxin were measured at admission, days 1–3 and 6. We explored the kinetics of release and the relationship between IFABP, citrulline and endotoxin values.

Results

IFABP was extremely high at admission and normalized at D3 (6668 pg/mL vs 39 pg/mL, p = 0.01). Lowest median of citrulline (N = 20–40 μmol/L) was attained at D2 (11 μmol/L at D2 vs 24 μmol/L at admission, p = 0.01) and tended to normalize at D6 (21 μmol/L). During ICU stay, 86% of patients presented a detectable endotoxemia. Highest endotoxin level was positively correlated with highest IFABP level (R² = 0.31, p = 0.01) and was inversely correlated with lowest plasma citrulline levels (R² = 0.55, p < 0.001). Endotoxin levels increased between admission and D2 in patients with post-resuscitation shock, whereas it decreases in patients with no shock (median +0.33 EU vs −0.19 EU, p = 0.03). Highest endotoxin level was positively correlated with D3 SOFA score (R² = 0.45, p = 0.004).

Conclusion

Biomarkers of intestinal injury are altered after cardiac arrest and are associated with endotoxemia. This could worsen post-resuscitation shock and organ failure.     

Hyperfibrinolysis in out of hospital cardiac arrest is associated with markers of hypoperfusion

Aim of the study

This study investigated the incidence of hyperfibrinolysis upon emergency department (ED) admission in patients with out of hospital cardiac arrest (OHCA), and the association of the degree of hyperfibrinolysis with markers of hypoperfusion.

Methods

From 30 OHCA patients, cardiopulmonary resuscitation (CPR) time, pH, base excess (BE), and serum lactate were measured upon ED admission. A 20% decrease of rotational thromboelastometry maximum clot firmness (MCF) was defined as hyperfibrinolysis. Lysis parameters included maximum lysis (ML), lysis onset time (LOT) and lysis index at 30 and 45 min (LI30/LI45). The study was approved by the Human Subjects Committee.

Results

Hyperfibrinolysis was present in 53% of patients. Patients with hyperfibrinolysis had longer median CPR times (36 (15–55) vs. 10 (7–18) min; P = 0.001), a prolonged activated partial thromboplastin time (54 ± 16 vs. 38 ± 10 s; P = 0.006) and elevated D-dimers (6.1 ± 2.1 vs. 2.3 ± 2.0 μg/ml; P = 0.02) when compared to patients without hyperfibrinolysis. Hypoperfusion markers, including pH (6.96 ± 0.11 vs. 7.17 ± 0.15; P < 0.001), base excess (−20.01 ± 3.53 vs. −11.91 ± 6.44; P < 0.001) and lactate (13.1 ± 3.7 vs. 8.0 ± 3.7 mmol/l) were more disturbed in patients with hyperfibrinolysis than in non-hyperfibrinolytic subjects, respectively. The LOT showed a good association with CPR time (r = −0.76; P = 0.003) and lactate (r = −0.68; P = 0.01), and was longer in survivors (3222 ± 34 s) than in non-survivors (1356 ± 833; P = 0.044).

Conclusion

A substantial part of OHCA patients develop hyperfibrinolysis in association with markers for hypoperfusion. Our data further suggest that the time to the onset of clot lysis may be an important marker for the severity of hyperfibrinolysis and patient outcome.     

Ankle range of motion is key to gait efficiency in adolescents with cerebral palsy

Background

Gait in young people with cerebral palsy is inefficient and there is a lack of relevant indicators for monitoring the problem. In particular, the impact of gait kinematics on gait efficiency is not well documented. The aim of this study is to examine the relationship between gait efficiency, gait kinematics, lower limb muscle strength, and muscular spasticity in adolescents with cerebral palsy.

Methods

Ten ambulatory adolescents with spastic cerebral palsy were recruited. The energy expenditure index during gait, gait kinematics, flexion and extension knee isometric muscle strength, and quadriceps spasticity were assessed.

Findings

Energy expenditure index (1.5 (0.7) beats/m) was strongly correlated with the ankle and knee flexion/extension ranges of motion (r = −0.82, P < 0.01 and r = −0.70, P < 0.02, respectively) and also with maximal plantar flexion (r = 0.74, P < 0.05) during gait. Knee flexion strength was the only strength measurement correlated with energy expenditure index (r = −0.85; P < 0.01).

Interpretation

This study suggests that ankle and knee flexion/extension ranges of motion during gait are key kinematics factors in gait efficiency in adolescents with cerebral palsy.     

Prehospital therapeutic hypothermia after cardiac arrest: A systematic review and meta-analysis of randomized controlled trials

Background

Therapeutic hypothermia has been recommended for the treatment of cardiac arrest patients who remain comatose after the return of spontaneous circulation. However, the optimal time to initiate therapeutic hypothermia remains unclear. The objective of the present study is to assess the effectiveness and safety of prehospital therapeutic hypothermia after cardiac arrest.

Methods

Databases such as MEDLINE, Embase, and Cochrane Library were searched from their establishment date to May of 2012 to retrieve randomized control trials on prehospital therapeutic hypothermia after cardiac arrest. Thereafter, the studies retrieved were screened based on predefined inclusion and exclusion criteria. Data were extracted and the quality of the included studies was evaluated. A meta-analysis was performed by using the Cochrane Collaboration Review Manager 5.1.6 software.

Results

Five studies involving 633 cases were included, among which 314 cases were assigned to the treatment group and the other 319 cases to the control group. The meta-analysis indicated that prehospital therapeutic hypothermia after cardiac arrest produced significant differences in temperature on hospital admission compared with in-hospital therapeutic hypothermia or normothermia (patient data; mean difference = −0.95; 95% confidence interval −1.15 to −0.75; I² = 0%). However, no significant differences were observed in the survival to the hospital discharge, favorable neurological outcome at hospital discharge, and rearrest. The risk of bias was low; however, the quality of the evidence was very low.

Conclusion

This review demonstrates that prehospital therapeutic hypothermia after cardiac arrest can decrease temperature on hospital admission. On the other hand, regarding the survival to hospital discharge, favorable neurological outcome at hospital discharge, and rearrest, our meta-analysis and review produces non-significant results. Using the Grading of Recommendations, Assessment, Development and Evaluation methodology, we conclude that the quality of evidence is very low.     

Hypokalemia during the cooling phase of therapeutic hypothermia and its impact on arrhythmogenesis

Background

Mild to moderate therapeutic hypothermia (TH) has been shown to improve survival and neurological outcome in patients resuscitated from out-of-hospital cardiac arrest (OHCA) with ventricular fibrillation (VF) as the presenting rhythm. This approach entails the management of physiological variables which fall outside the realm of conventional critical cardiac care. Management of serum potassium fluxes remains pivotal in the avoidance of lethal ventricular arrhythmia.

Methods

We retrospectively analyzed potassium variability with TH and performed correlative analysis of QT intervals and the incidence of ventricular arrhythmia.

Results

We enrolled 94 sequential patients with OHCA, and serum potassium was followed intensively. The average initial potassium value was 3.9 ± 0.7 mmol l⁻¹ and decreased to a nadir of 3.2 ± 0.7 mmol l⁻¹ at 10 h after initiation of cooling (p < 0.001). Eleven patients developed sustained polymorphic ventricular tachycardia (PVT) with eight of these occurring during the cooling phase. The corrected QT interval prolonged in relation to the development of hypothermia (p < 0.001). Hypokalemia was significantly associated with the development of PVT (p = 0.002), with this arrhythmia being most likely to develop in patients with serum potassium values of less than 2.5 mmol l⁻¹ (p = 0.002). Rebound hyperkalemia did not reach concerning levels (maximum 4.26 ± 0.8 mmol l⁻¹ at 40 h) and was not associated with the occurrence of ventricular arrhythmia. Furthermore, repletion of serum potassium did not correlate with the development of ventricular arrhythmia.

Conclusions

Therapeutic hypothermia is associated with a significant decline in serum potassium during cooling. Hypothermic core temperatures do not appear to protect against ventricular arrhythmia in the context of severe hypokalemia and cautious supplementation to maintain potassium at 3.0 mmol l⁻¹ appears to be both safe and effective.     

Evaluation of pre-arrest morbidity score and prognosis after resuscitation score and other clinical variables associated with in-hospital cardiac arrest in southern Sweden

Objective

To evaluate pre-arrest morbidity score (PAM), prognosis after resuscitation score (PAR) and to identify additional clinical variables associated with survival after in-hospital cardiac arrest (IHCA) treated with cardiopulmonary resuscitation (CPR).

Methods

A retrospective observational study involving all cases of IHCA at Skåne University Hospital Malmö 2007–2010.

Results

Two-hundred-eighty-seven cases of IHCA were identified (61.3% male; mean age 70 years) of whom 20.2% survived until discharge. The odds ratio (95% confidence interval) for death prior to discharge was 6.49 (1.50–28.19) (p = 0.013) for PAM > 6 and 3.88 (1.95–7.73) (p < 0.001) for PAR > 4. At PAM- and PAR-scores >5, specificity exceeded 90%, while sensitivity was only 20–30%. The odds ratio for in-hospital mortality was 0.38 (0.20–0.72) (p = 0.003) for patients with cardiac monitoring, 9.86 (5.08–19.12) (p < 0.001) for non-shockable vs shockable rhythm, 0.32 (0.15–0.69) (p = 0.004) for presence of ST-elevation myocardial infarction (STEMI), 0.27 (0.09–0.78) (p = 0.016) for patients with independent Activities of Daily Life (ADL) and 13.86 (1.86–103.46) (p = 0.010) for patients with malignancies. Heart rate (HR) on admission (per bpm) [1.024 (1.009–1.040) (p = 0.002)] and sodium plasma concentration on admission (per mmol l⁻¹) [0.92 (0.85–0.99) (p = 0.023)] were significantly associated with in-hospital mortality.

Conclusion

PAM- and PAR-scores do not sufficiently discriminate between in-hospital death and survival after IHCA to be used as clinical tools guiding CPR decisions. We confirm that malignancy is associated with increased in-hospital mortality, and cardiac monitoring, shockable rhythm, STEMI and independent ADL, with decreased in-hospital mortality. Interestingly, our results suggest that HR and plasma sodium concentration upon admission may represent new tools for risk stratification.     

Efficacy of low-level laser therapy applied at acupuncture points in knee osteoarthritis: a randomised double-blind comparative trial

Objective

To evaluate the efficacy of low-level laser therapy (LLLT) applied to acupuncture points on the knee joint in combination with exercise and advice in patients with knee osteoarthritis.

Design

Randomised, double-blind, comparative clinical trial.

Participants

Forty-nine patients with knee osteoarthritis were assigned at random into two groups: active laser group (n = 26) and placebo laser group (n = 23).

Intervention

Using a gallium aluminium arsenide laser device, patients received either active or placebo LLLT at five acupuncture points on the affected knee during nine sessions.

Outcome measures

Patients were assessed using a visual analogue scale (VAS) and the Saudi Knee Function Scale (SKFS) at baseline, the fifth treatment session, the last treatment session, 6 weeks post intervention and 6 months post intervention.

Results

VAS scores showed a significant improvement in the active laser group compared with the placebo laser group at 6 weeks post intervention [mean difference −1.3, 95% confidence interval (CI) of the difference −2.4 to −0.3; P = 0.014] and 6 months post intervention (mean difference −1.8, 95% CI of the difference −3.0 to −0.7; P = 0.003) using the independent samples test. SKFS scores also showed a significant improvement in the active laser group compared with the placebo laser group at the last treatment session (median difference −15, 95% CI of the difference −27 to −2; P = 0.035) and 6 months post intervention (median difference −21, 95% CI of the difference −34 to −7; P = 0.006) using the Mann–Whitney U test.

Conclusions

The results demonstrate that short-term application of LLLT to specific acupuncture points in association with exercise and advice is effective in reducing pain and improving quality of life in patients with knee osteoarthritis.