ABSTRACT
BACKGROUND: Oxygen is liberally administered in intensive care units (ICUs). Nevertheless, ICU doctors' preferences for supplementing oxygen are inadequately described. The aim was to identify ICU doctors' preferences for arterial oxygenation levels in mechanically ventilated adult ICU patients. METHODS: In April to August 2016, an online multiple-choice 17-part-questionnaire was distributed to 1080 ICU doctors in seven Northern European countries. Repeated reminder e-mails were sent. The study ended in October 2016. RESULTS: The response rate was 63%. When evaluating oxygenation 52% of respondents rated arterial oxygen tension (PaO2 ) the most important parameter; 24% a combination of PaO2 and arterial oxygen saturation (SaO2 ); and 23% preferred SaO2 . Increasing, decreasing or not changing a default fraction of inspired oxygen of 0.50 showed preferences for a PaO2 around 8 kPa in patients with chronic obstructive pulmonary disease, a PaO2 around 10 kPa in patients with healthy lungs, acute respiratory distress syndrome or sepsis, and a PaO2 around 12 kPa in patients with cardiac or cerebral ischaemia. Eighty per cent would accept a PaO2 of 8 kPa or lower and 77% would accept a PaO2 of 12 kPa or higher in a clinical trial of oxygenation targets. CONCLUSION: Intensive care unit doctors preferred PaO2 to SaO2 in monitoring oxygen treatment when peripheral oxygen saturation was not included in the question. The identification of PaO2 as the preferred target and the thorough clarification of preferences are important when ascertaining optimal oxygenation targets. In particular when designing future clinical trials of higher vs lower oxygenation targets in ICU patients.
Subject(s)
Intensive Care Units , Oxygen/blood , Respiration, Artificial , Humans , Oxygen/toxicity , Physicians , Pulmonary Disease, Chronic Obstructive/metabolism , Respiratory Distress Syndrome/metabolismABSTRACT
BACKGROUND: Kidney disease after out-of-hospital cardiac arrest (OHCA) is incompletely described. We examined the occurrence of acute kidney injury (AKI) in OHCA patients and impact of AKI, with or without renal replacement therapy (RRT), on 6-month mortality and neurological outcome. METHODS: Prospective study at Oslo University Hospital, Oslo, Norway. Adult resuscitated comatose OHCA patients treated with targeted temperature management at 33°C for 24 h were included. AKI and chronic kidney disease (CKD) were classified according to the Kidney Disease Improving Global Outcomes (KDIGO) guidelines. Main outcomes were 6-month mortality and good neurological outcome defined as Cerebral Performance Category 1-2. RESULTS: Among 245 included patients (84% males, mean age 61 years), 11 (4%) had previously known CKD and 112 (46%) developed AKI. Overall 6-month outcome revealed that 112 (46%) died and 123 (50%) had good neurological outcome. Compared with no kidney disease, the presence of AKI was significantly associated with 6-month mortality (odds ratio (OR) 3.17, 95% confidence interval (CI) 1.95-5.43, P < 0.001) and good neurological outcome (OR 0.28, 95% CI 0.16-0.48, P < 0.001). Six-month mortality (50 vs. 61%, P = 0.401) and frequency of good neurological outcome (44 vs. 35%, P = 0.417) were not statistically different in AKI patients with or without RRT, also after excluding patients where RRT was withheld due to futility. CONCLUSIONS: Kidney disease occurred in about half of patients successfully resuscitated from OHCA. Presence of AKI, but not RRT, was associated with unfavourable 6-month outcome.
Subject(s)
Acute Kidney Injury/mortality , Out-of-Hospital Cardiac Arrest/mortality , Acute Kidney Injury/therapy , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Renal Replacement TherapyABSTRACT
Long QT syndrome (LQTS) is a genetic or acquired condition characterised by a prolonged QT interval on the surface electrocardiogram (ECG) and is associated with a high risk of sudden cardiac death because of polymorph ventricular tachyarrhythmia called Torsade de Pointes arrhythmia. Drug-induced LQTS can occur as a side effect of commonly used cardiac and non-cardiac drugs in predisposed patients, often with baseline QT prolongation lengthened by medication and/or electrolyte disturbances. Hospitalised patients often have several risk factors for proarrhythmic response, such as advanced age and structural heart disease. Patients in the intensive care unit (ICU) are particularly prone to develop drug induced LQTS because they receive several different intravenous medications. Additionally, they might have impaired drug elimination because of reduced kidney and/or liver function, and also drug-drug-interactions. The clinical symptoms and signs of LQTS range from asymptomatic patients to sudden death because of malignant arrhythmias, and it is therefore important to recognise the clinical characteristics and typical ECG changes. Treatment of acquired LQTS is mainly awareness, identification and discontinuation of QT prolonging drugs, in addition to eventually supplement of magnesium and potassium. Overdrive cardiac pacing is highly effective in preventing recurrences, and antiarrhythmic drugs should be avoided. Recent data suggest that QT prolongation is quite common in ICU patients and adversely affects patient mortality. Thus, high-risk patients should be sufficiently monitored, and the use of medications known to cause drug-induced LQTS might have to be restricted.
Subject(s)
Arrhythmias, Cardiac/chemically induced , Critical Care/methods , Long QT Syndrome/chemically induced , Anti-Arrhythmia Agents/therapeutic use , Arrhythmias, Cardiac/drug therapy , Drug-Related Side Effects and Adverse Reactions , Humans , Intensive Care Units , Long QT Syndrome/drug therapyABSTRACT
BACKGROUND: Aim of this experimental study was to compare haemodynamic effects and outcome with early administration of amiodarone and adrenaline vs. adrenaline alone in pigs with prolonged ventricular fibrillation (VF). METHODS: After 8 min of untreated VF arrest, bolus doses were administered of adrenaline (0.02 mg/kg) and either amiodarone (5 mg/kg) or saline (n = 8 per group) after randomisation. Cardiopulmonary resuscitation (CPR) was commenced immediately after drug administration, and defibrillation was attempted 2 min later. CPR was resumed for another 2 min after each defibrillation attempt, and the same dose of adrenaline was given every 4th minute during CPR. Haemodynamic monitoring and mechanical ventilation continued for 6 h after return of spontaneous circulation (ROSC), and the pigs were euthanised at 48 h. Researchers were blinded for drug groups throughout the study. RESULTS: There was no difference in rates of ROSC and 48-h survival with amiodarone vs. saline (5/8 vs. 7/8 and 0/8 vs. 3/8, respectively). Diastolic aortic pressure and coronary perfusion pressure were significantly lower with amiodarone during CPR and 1 min after ROSC (P < 0.05). The number of electric shocks required for terminating VF, time to ROSC and adrenaline dose were significantly higher with amiodarone (P < 0.01). The incidence of post-resuscitation tachyarrhythmias tended to be higher in the saline group (P = 0.081). CONCLUSION: Early administration of amiodarone did not improve ROSC or 48-h survival rates, and was associated with worse haemodynamics in this swine model of cardiac arrest.
Subject(s)
Amiodarone/therapeutic use , Anti-Arrhythmia Agents/therapeutic use , Cardiopulmonary Resuscitation/methods , Heart Arrest/drug therapy , Animals , Electric Countershock , Epinephrine/pharmacology , Female , Heart Arrest/physiopathology , Hemodynamics/physiology , Odds Ratio , Respiration, Artificial , Resuscitation , Shock/etiology , Shock/therapy , Swine , Vasoconstrictor Agents/pharmacologyABSTRACT
INTRODUCTION: Therapeutic hypothermia (TH) after out-of-hospital cardiac arrest (OHCA) was adopted early in Norway. Since 2004 the general recommendation has been to cool all unconscious OHCA patients treated in the intensive care unit (ICU), but the decision to cool individual patients was left to the responsible physician. We assessed factors that were associated with use of TH and predicted survival. METHOD: We conducted a retrospective observational study of prospectively collected cardiac arrest and ICU registry data from 2004 to 2008 at three university hospitals. RESULTS: A total of 715 unconscious patients older than 18 years of age, who suffered OHCA of both cardiac and non-cardiac causes, were included. With an overall TH use of 70%, the survival to discharge was 42%, with 90% of the survivors having a favourable cerebral outcome. Known positive prognostic factors such as witnessed arrest, bystander cardio pulmonary resuscitation (CPR), shockable rhythm and cardiac origin were all positive predictors of TH use and survival. On the other side, increasing age predicted a lower utilisation of TH: Odds Ratio (OR), 0.96 (95% CI, 0.94 to 0.97); as well as a lower survival: OR 0.96 (95% CI, 0.94 to 0.97). Female gender was also associated with a lower use of TH: OR 0.65 (95% CI, 0.43 to 0.97); and a poorer survival: OR 0.57 (95% CI, 0.36 to 0.92). After correcting for other prognostic factors, use of TH remained an independent predictor of improved survival with OR 1.91 (95% CI 1.18-3.06; P <0.001). Analysing subgroups divided after initial rhythm, these effects remained unchanged for patients with shockable rhythm, but not for patients with non-shockable rhythm where use of TH and female gender lost their predictive value. CONCLUSIONS: Although TH was used in the majority of unconscious OHCA patients admitted to the ICU, actual use varied significantly between subgroups. Increasing age predicted both a decreased utilisation of TH as well as lower survival. Further, in patients with a shockable rhythm female gender predicted both a lower use of TH and poorer survival. Our results indicate an underutilisation of TH in some subgroups. Hence, more research on factors affecting TH use and the associated outcomes in subgroups of post-resuscitation patients is needed.
Subject(s)
Hypothermia, Induced/methods , Intensive Care Units , Out-of-Hospital Cardiac Arrest/mortality , Out-of-Hospital Cardiac Arrest/therapy , Patient Admission , Unconscious, Psychology , Adult , Aged , Aged, 80 and over , Female , Humans , Hypothermia, Induced/trends , Intensive Care Units/trends , Male , Middle Aged , Out-of-Hospital Cardiac Arrest/diagnosis , Patient Admission/trends , Predictive Value of Tests , Prospective Studies , Registries , Retrospective Studies , Survival Rate/trends , Treatment OutcomeABSTRACT
BACKGROUND: Therapeutic hypothermia (TH) after cardiac arrest protects from neurological sequels and death and is recommended in guidelines. The Hypothermia Registry was founded to the monitor outcome, performance and complications of TH. METHODS: Data on out-of-hospital cardiac arrest (OHCA) patients admitted to intensive care for TH were registered. Hospital survival and long-term outcome (6-12 months) were documented using the Cerebral Performance Category (CPC) scale, CPC 1-2 representing a good outcome and 3-5 a bad outcome. RESULTS: From October 2004 to October 2008, 986 TH-treated OHCA patients of all causes were included in the registry. Long-term outcome was reported in 975 patients. The median time from arrest to initiation of TH was 90 min (interquartile range, 60-165 min) and time to achieving the target temperature (< or =34 degrees C) was 260 min (178-400 min). Half of the patients underwent coronary angiography and one-third underwent percutaneous coronary intervention (PCI). Higher age, longer time to return of spontaneous circulation, lower Glasgow Coma Scale at admission, unwitnessed arrest and initial rhythm asystole were all predictors of bad outcome, whereas time to initiation of TH and time to reach the goal temperature had no significant association. Bleeding requiring transfusion occurred in 4% of patients, with a significantly higher risk if angiography/PCI was performed (2.8% vs. 6.2%P=0.02). CONCLUSIONS: Half of the patients survived, with >90% having a good neurological function at long-term follow-up. Factors related to the timing of TH had no apparent association to outcome. The incidence of adverse events was acceptable but the risk of bleeding was increased if angiography/PCI was performed.
Subject(s)
Heart Arrest/therapy , Hypothermia, Induced , Age Factors , Aged , Angioplasty, Balloon, Coronary , Blood Transfusion , Body Temperature/physiology , Coronary Angiography , Critical Care , Female , Glasgow Coma Scale , Heart Arrest/mortality , Hemorrhage/epidemiology , Humans , Hypothermia, Induced/adverse effects , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , Registries , Shock, Cardiogenic/epidemiology , Survival Analysis , Treatment OutcomeABSTRACT
BACKGROUND AND AIM: Sudden cardiac arrest survivors suffer from ischaemic brain injury that may lead to poor neurological outcome and death. The reperfusion injury that occurs is associated with damaging biochemical reactions, which are suppressed by mild therapeutic hypothermia (MTH). In several studies MTH has been proven to be safe, with few complications and improved survival, and is recommended by the International Liaison of Committee on Resuscitation. The aim of this paper is to recommend clinical practice guidelines for MTH treatment after cardiac arrest from the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI). METHODS: Relevant studies were identified after two consensus meetings of the SSAI Task Force on Therapeutic Hypothermia (SSAITFTH) and via literature search of the Cochrane Central Register of Controlled Trials and Medline. Evidence was assessed and consensus opinion was used when high-grade evidence (Grade of Recommendation, GOR) was unavailable. A management strategy was developed as a consensus from the evidence and the protocols in the participating countries. RESULTS AND CONCLUSION: Although proven beneficial only for patients with initial ventricular fibrillation (GOR A), the SSAITFTH also recommend MTH after restored spontaneous circulation, if active treatment is chosen, in patients with initial pulseless electrical activity and asystole (GOR D). Normal ethical considerations, premorbid status, total anoxia time and general condition should decide whether active treatment is required or not. MTH should be part of a standardized treatment protocol, and initiated as early as possible after indication and treatment have been decided (GOR E). There is insufficient evidence to make definitive recommendations among techniques to induce MTH, and we do not know the optimal target temperature, duration of cooling and rewarming time. New studies are needed to address the question as to how MTH affects, for example, prognostic factors.
Subject(s)
Heart Arrest , Hypothermia, Induced/methods , Resuscitation/methods , Heart Arrest/diagnosis , Humans , Hypothermia, Induced/adverse effects , Scandinavian and Nordic Countries , Time FactorsABSTRACT
We present two cases of unrecognized endotracheal tube misplacements in out-of-hospital cardiopulmonary resuscitation recognized by the analysis of transthoracic impedance. In Case 1, ventilation-induced changes in transthoracic impedance disappeared after an intubation attempt corresponding to oesophageal intubation. This was clinically recognized after several minutes, the endotracheal tube was repositioned and alterations in transthoracic impedance resumed. In Case 2, the initial ventilation-induced signal change following endotracheal intubation weakened after a few minutes. At that time, the defibrillator gave vocal and visual feedback to the rescuers on ventilatory inactivity, a pharyngeal air leak was discovered simultaneously and the tube was found to be dislodged. Continuous monitoring of transthoracic impedance provided by the defibrillator during cardiopulmonary resuscitation may contribute to the early detection of an initially misplaced or later dislodged endotracheal tube.
Subject(s)
Cardiopulmonary Resuscitation/methods , Intubation, Intratracheal/adverse effects , Aged , Cardiography, Impedance , Female , Humans , Male , Middle Aged , Treatment OutcomeABSTRACT
A large proportion of deaths in the Western World are caused by ischaemic heart disease. Among these patients a majority die outside hospital due to sudden cardiac death. The prognosis among these patients is in general, poor. However, a significant proportion are admitted to a hospital ward alive. The proportion of patients who survive the hospital phase of an out of hospital cardiac arrest varies considerably. Several treatment strategies are applicable during the post resuscitation care phase, but the level of evidence is weak for most of them. Four treatments are recommended for selected patients based on relatively good clinical evidence: therapeutic hypothermia, beta-blockers, coronary artery bypass grafting, and an implantable cardioverter defibrillator. The patient's cerebral function might influence implementation of the latter two alternatives. There is some evidence for revascularisation treatment in patients with suspected myocardial infarction. On pathophysiological grounds, an early coronary angiogram is a reasonable alternative. Further randomised clinical trials of other post resuscitation therapies are essential.
Subject(s)
Critical Care/methods , Resuscitation/methods , HumansABSTRACT
INTRODUCTION: While pre-hospital factors related to outcome after out-of-hospital cardiac arrest (OHCA) are well known, little is known about possible in-hospitals factors related to outcome. HYPOTHESIS: Some in-hospital factors are associated with outcome in terms of survival. MATERIAL AND METHODS: An historical cohort observational study of all patients admitted to hospital with a spontaneous circulation after OHCA due to a cardiac cause in four different regions in Norway 1995-1999: Oslo, Akershus, Østfold and Stavanger. RESULTS: In Oslo, Akershus, Østfold and Stavanger 98, 84, 91 and 186 patients were included, respectively. Hospital mortality was higher in Oslo (66%) and Akershus (64%) than in Østfold (56%) and Stavanger (44%), P=0.002. By multivariate analysis the following pre-arrest and pre-hospital factors were associated with in-hospital survival: age Subject(s)
Cardiopulmonary Resuscitation
, Emergency Medical Services
, Heart Arrest/therapy
, Hospital Mortality
, Aged
, Cohort Studies
, Female
, Heart Arrest/mortality
, Humans
, Male
, Middle Aged
, Multivariate Analysis
, Norway/epidemiology
, Risk Factors
, Survival Rate
, Treatment Outcome
ABSTRACT
UNLABELLED: We evaluated ventricular fibrillation frequency and amplitude variables to predict successful countershock, defined as pulse-generating electrical activity. We also elucidated whether bystander cardiopulmonary resuscitation (CPR) influences these electrocardiogram (ECG) variables. In 89 patients with out-of-hospital cardiac arrest, ECG recordings of 594 countershock attempts were collected and analyzed retrospectively. By using fast Fourier transformation analysis of the ventricular fibrillation ECG signal in the frequency range 0.333-15 Hz (median [range]), median frequency, dominant frequency, spectral edge frequency, and amplitude were as follows: 4.4 (2.4-7.5) Hz, 4.0 (0.7-7.0) Hz, 7.7 (3.7-13.7) Hz, and 0.94 (0.24-1.95) mV, respectively, before successful countershock (n = 59). These values were 3.8 (0.8-7.7) Hz (P = 0.0002), 3.0 (0.3-9.7) Hz (P < 0.0001), 7.3 (2.0-14.0) Hz (P < 0.05), and 0.53 (0.03-3.03) mV (P < 0.0001), respectively, before unsuccessful countershock (n = 535). In patients in whom bystander CPR was performed (n = 51), ventricular fibrillation frequency and amplitude before the first defibrillation attempt were higher than in patients without bystander CPR (n = 38) (median frequency, 4.4 [2.4-7.5] vs 3.7 [1.8-5.3] Hz, P < 0.0001; dominant frequency, 3.8 [0.9-7.7] vs 2.6 [0.8-5.9] Hz, P < 0.0001; spectral edge frequency, 8.4 [4.8-12.9] vs 7.2 [3.9-12.1] Hz, P < 0.05; amplitude, 0.79 [0.06-4.72] vs 0.67 [0.16-2.29] mV, P = 0.0647). Receiver operating characteristic curves demonstrate that successful countershocks will be best discriminated from unsuccessful countershocks by ventricular fibrillation amplitude (3000-ms epoch). At 73% sensitivity, a specificity of 67% was obtained with this variable. IMPLICATIONS: In patients with out-of-hospital cardiac arrest, successful countershocks will be best discriminated from unsuccessful countershocks by ventricular fibrillation amplitude (3000-ms epoch). At 73% sensitivity, a specificity of 67% was obtained with this variable.
Subject(s)
Electric Countershock , Electrocardiography , Emergency Medical Services , Heart Arrest/therapy , Ventricular Fibrillation/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Female , Heart Arrest/diagnosis , Heart Arrest/physiopathology , Humans , Male , Middle Aged , Predictive Value of Tests , ROC Curve , Sensitivity and SpecificityABSTRACT
INTRODUCTION: An important factor determining survival after out-of-hospital cardiac arrest is how fast the ambulance personnel can reach the patient. MATERIALS AND METHODS: In a two-year period between 1996 and 1998, all ambulance calls to patients with out-of-hospital cardiac arrest in Oslo were evaluated. Of 1,026 cardiac arrests, 130 were excluded because of missing data. RESULTS: The median ambulance response interval was 7.2 min (5.7-9.0 as 25-75% percentiles). There was a tendency to shorter response intervals to the central parts of Oslo with medians between 3 and 4 min, while 14 more peripheral boroughs had median response intervals over 8 min. Of the 627 cases where the ambulance starting point was registered, 76% were from the only ambulance station in Oslo, located downtown. INTERPRETATION: In our opinion, the median ambulance response interval is unsatisfactory in large parts of Oslo, as a long response time gives a dramatically lower survival rate after cardiac arrest. A reorganisation and decentralization of the Oslo Emergency Medical Service System seems necessary.
Subject(s)
Ambulances , Emergency Medical Services , Heart Arrest , Ambulances/standards , Ambulances/statistics & numerical data , Emergency Medical Services/standards , Emergency Medical Services/statistics & numerical data , Heart Arrest/epidemiology , Heart Arrest/mortality , Humans , Norway/epidemiology , Retrospective Studies , Time and Motion Studies , Urban Health Services/statistics & numerical dataABSTRACT
The frequency spectrum of the ECG in ventricular fibrillation (VF) correlates with myocardial perfusion and might predict defibrillation success defined as return of spontaneous circulation (ROSC). The predictive power increases when more spectral variables are combined, but the complex information can be difficult to handle during the intensity of CPR. We therefore developed a method for expressing this multidimensional information in a single reproducible variable reflecting the probability of defibrillation success. This is based on the highest performing predictor for ROSC after 883 shocks given to 156 patients with VF. This was a combination of two decorrelated spectral features based on a principal component analysis of an original feature set with information on centroid frequency, peak power frequency, spectral flatness and energy. The function "Probability of defibrillation success" (P(ROSC)(v)) was developed by a 2-dimensional histogram technique. P(ROSC)(v) discriminated between shocks followed by ROSC and No-ROSC (P<0.0001). The present methodology indicates a possible way to develop a CPR monitor.
Subject(s)
Electric Countershock/methods , Heart Arrest/therapy , Cardiopulmonary Resuscitation/methods , Electrocardiography , Electrocardiography, Ambulatory , Humans , Treatment OutcomeABSTRACT
The purpose of this study was to assess whether the artifacts presented by precordial compressions during cardiopulmonary resuscitation could be removed from the human electrocardiogram (ECG) using a filtering approach. This would allow analysis and defibrillator charging during ongoing precordial compressions yielding a very important clinical improvement to the treatment of cardiac arrest patients. In this investigation we started with noise-free human ECGs with ventricular fibrillation (VF) and ventricular tachycardia (VT) records. To simulate a realistic resuscitation situation, we added a weighted artifact signal to the human ECG, where the weight factor was chosen to provide the desired signal-to-noise ratio (SNR) level. As artifact signals we used ECGs recorded from animals in asystole during precordial compressions at rates 60, 90, and 120 compressions/min. The compression depth and the thorax impedance was also recorded. In a real-life situation such reference signals are available and, using an adaptive multichannel Wiener filter, we construct an estimate of the artifact signal, which subsequently can be subtracted from the noisy human ECG signal. The success of the proposed method is demonstrated through graphic examples, SNR, and rhythm classification evaluations.
Subject(s)
Cardiopulmonary Resuscitation , Electrocardiography/statistics & numerical data , Biomedical Engineering , Electric Countershock , Humans , Signal Processing, Computer-Assisted , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/physiopathology , Tachycardia, Ventricular/therapy , Ventricular Fibrillation/diagnosis , Ventricular Fibrillation/physiopathology , Ventricular Fibrillation/therapyABSTRACT
BACKGROUND: In 156 patients with out-of-hospital cardiac arrest of cardiac cause, we analyzed the ability of 4 spectral features of ventricular fibrillation before a total of 868 shocks to discriminate or not between segments that correspond to return of spontaneous circulation (ROSC). METHODS AND RESULTS: Centroid frequency, peak power frequency, spectral flatness, and energy were studied. A second decorrelated feature set was generated with the coefficients of the principal component analysis transformation of the original feature set. Each feature set was split into training and testing sets for improved reliability in the evaluation of nonparametric classifiers for each possible feature combination. The combination of centroid frequency and peak power frequency achieved a mean+/-SD sensitivity of 92+/-2% and specificity of 27+/-2% in testing. The highest performing classifier corresponded to the combination of the 2 dominant decorrelated spectral features with sensitivity and specificity equal to 92+/-2% and 42+/-1% in testing or a positive predictive value of 0.15 and a negative predictive value of 0.98. Using the highest performing classifier, 328 of 781 shocks not leading to ROSC would have been avoided, whereas 7 of 87 shocks leading to ROSC would not have been administered. CONCLUSIONS: The ECG contained information predictive of shock therapy. This could reduce the delivery of unsuccessful shocks and thereby the duration of unnecessary "hands-off" intervals during cardiopulmonary resuscitation. The low specificity and positive predictive value indicate that other features should be added to improve performance.
Subject(s)
Electric Countershock , Heart Arrest/therapy , Ventricular Fibrillation/therapy , Electrocardiography , Heart Arrest/physiopathology , Humans , Predictive Value of Tests , Ventricular Fibrillation/physiopathologyABSTRACT
The correct tidal volume during cardiopulmonary resuscitation (CPR) is presently debated. While the European Resuscitation Council (ERC) and American Heart Association (AHA) previously recommended a tidal volume of 800-1200 ml, the ERC has recently reduced this to 400-600 ml. In a prospective, randomised study of 17 non-traumatic out-of-hospital cardiac arrest patients intubated and mechanically ventilated 12 min(-1) with 100% oxygen, we have therefore compared arterial blood gases generated with tidal volumes of 500 and 1000 ml. Mean time from cardiac arrest to arrival of the ambulance was 13+/-8 and 14+/-8 min in the two groups, respectively. Arterial blood samples were taken percutaneously 5 and 10-15 min after onset of the mechanical ventilation and analysed instantly. Pa(CO(2)) was significantly higher for a tidal volume of 500 than 1000 ml at both 5 and 10-15 min, 7.48+/-2.23 versus 3.70+/-0.83 kPa (P=0.002) and 7. 45+/-1.19 versus 3.98+/-1.58 kPa (P<0.001). The pH was lower for 500 than 1000 ml at 10-15 min, 7.01+/-0.10 versus 7.20+/-0.17 (P=0.034), with a strong trend in the same direction at 5 min (P=0.06). There was adequate oxygenation with no differences in Pa(O(2)) or BE at any time between the two groups, and no significant differences in any blood gas variables between the 5- and 10-15-min samples. We conclude that arterial normocapnia is not achieved with either tidal volume during advanced life support with non-rebreathing ventilation at 12 min(-1). What ventilation volume is required for CO(2) removal and oxygenation during basic life support with mouth-to-mouth ventilation cannot be extrapolated from the present data. In that situation the risk of gastric inflation, regurgitation and aspiration must also be taken into account.
Subject(s)
Cardiopulmonary Resuscitation/methods , Oxygen/blood , Tidal Volume/physiology , Aged , Aged, 80 and over , Cardiopulmonary Resuscitation/statistics & numerical data , Emergency Medical Services , Female , Heart Arrest/therapy , Humans , Male , Middle Aged , Prospective Studies , Pulmonary Ventilation , Risk Factors , Time FactorsABSTRACT
In a previous case report a standard chest compression successfully removed a foreign body from the airway after the Heimlich manoeuvre had failed. Based on this case, standard chest compressions and Heimlich manoeuvres were performed by emergency physicians on 12 unselected cadavers with a simulated complete airway obstruction in a randomised crossover design. The mean peak airway pressure was significantly lower with abdominal thrusts compared to chest compressions, 26.4+/-19.8 cmH(2)O versus 40.8+/-16.4 cmH(2)O, respectively (P=0.005, 95% confidence interval for the mean difference 5.3-23.4 cmH(2)O). Standard chest compressions therefore have the potential of being more effective than the Heimlich manoeuvre for the management of complete airway obstruction by a foreign body in an unconscious patient. Removal of the Heimlich manoeuvre from the resuscitation algorithm for unconscious patients with suspected airway obstruction will also simplify training.
Subject(s)
Airway Obstruction , Cardiopulmonary Resuscitation , First Aid , Adult , Aged , Airway Obstruction/therapy , Cadaver , Female , Humans , MaleABSTRACT
Previous research on memory and schizophrenia has relied on a limited number of global memory measures instead of a comprehensive assessment of various memory components. In addition, little effort has been directed at examining memory functioning in patients with early-onset schizophrenia. Published research often lacks a relevant neuropsychiatric comparison group to control for attention difficulties. Patients with Attention Deficit Hyperactivity Disorder (ADHD) were included in the present study for this purpose. To our knowledge, a direct comparison of the two patient groups on memory functions has never been made. In the present study, both adolescents with schizophrenia and adolescents with ADHD were compared on a comprehensive memory test battery. Nineteen adolescents with schizophrenia were compared to 20 ADHD adolescents and 30 normally functioning adolescents on measures of working memory and long-term episodic memory, including tests of verbal and visual memory, free recall and recognition memory. The performance of the adolescents with schizophrenia was impaired as compared to the normal group on most of the memory measures. They performed significantly more poorly than the adolescents with ADHD on the visual memory tests. The ADHD group scored more impaired than the schizophrenia group on working memory tests with focus on distractibility. The findings suggest a general memory deficit among adolescents with schizophrenia related to both verbal and visual material. Impairment on the measures of visual memory is specific to schizophrenia and does not characterise the ADHD subjects.
Subject(s)
Attention Deficit Disorder with Hyperactivity/complications , Memory Disorders/psychology , Schizophrenia/complications , Adolescent , Adolescent Behavior , Attention Deficit Disorder with Hyperactivity/psychology , Female , Humans , Male , Memory Disorders/etiology , Psychiatric Status Rating Scales , Visual PerceptionABSTRACT
What actually occurred during the two last links in the 'chain of survival': defibrillation and advanced life support (ALS), was studied in 156 patients with cardiac arrest of cardiac aetiology using the computer recording of the defibrillator and the Utstein-style data record. Ten patients (6%) survived. The ECG artefacts caused by chest compressions enabled a detailed analysis of compression rates (median 108 min(-1)) and duration of important compression free periods. The time from initiation of monitoring during asystole until chest compressions were initiated was median 29 s, significantly shorter than during electromechanical dissociation (EMD, 109 s; P < 0.001). These times were both significantly longer than the median time from initiation of monitoring until the first shock was given in cases with VF (19 s; P < 0.001). A total of 883 shocks (median six shocks) were administered to 110 patients with a significant difference in number of shocks between survivors and non-survivors, one versus seven, respectively. The success rate for the first shock and all shocks defined as non-VT/VF 5 s after the shock, was 75 and 63%, respectively. However, just 10% of all shocks resulted in a rhythm with a pulse and only 4% resulted in sustained return of spontaneous circulation (ROSC). An isoelectric period followed 38% of the shocks, and in 27% this lasted more than 20 s, with five patients obtaining electrical activity with a pulse after more than 30 s of isoelectric ECG. Thoracic impedance did not affect the shock efficacy. The method of analysing resuscitation we describe may be useful for quality improvement.