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Kjetil Sunde

Publications and source records attributed to Kjetil Sunde.

10 recordsLinked to original sources

Haemodynamic effects of adrenaline (epinephrine) depend on chest compression quality during cardiopulmonary resuscitation in pigs.

BACKGROUND: Adrenaline (epinephrine) is used during cardiopulmonary resuscitation (CPR) based on animal experiments without supportive clinical data. Clinically CPR was reported recently to have much poorer quality than expected from international guidelines and what is generally done in laboratory experiments. We have studied the haemodynamic effects of adrenaline during CPR with good laboratory quality and with quality simulating clinical findings and the feasibility of monitoring these effects through VF waveform analysis. METHODS AND RESULTS: After 4 min of cardiac arrest, followed by 4 min of basic life support, 14 pigs were randomised to ClinicalCPR (intermittent manual chest compressions, compression-to-ventilation ratio 15:2, compression depth 30-38 mm) or LabCPR (continuous mechanical chest compressions, 12 ventilations/min, compression depth 45 mm). Adrenaline 0.02 mg/kg was administered 30 s thereafter. Plasma adrenaline concentration peaked earlier with LabCPR than with ClinicalCPR, median (range), 90 (30, 150) versus 150 (90, 270) s (p = 0.007), respectively. Coronary perfusion pressure (CPP) and cortical cerebral blood flow (CCBF) increased and femoral blood flow (FBF) decreased after adrenaline during LabCPR (mean differences (95% CI) CPP 17 (6, 29) mmHg (p = 0.01), FBF -5.0 (-8.8, -1.2) ml min(-1) (p = 0.02) and median difference CCBF 12% of baseline (p = 0.04)). There were no significant effects during ClinicalCPR (mean differences (95% CI) CPP 4.7 (-3.2, 13) mmHg (p = 0.2), FBF -0.2 (-4.6, 4.2) ml min(-1)(p = 0.9) and CCBF 3.6 (-1.8, 9.0)% of baseline (p = 0.15)). Slope VF waveform analysis reflected changes in CPP. CONCLUSION: Adrenaline improved haemodynamics during laboratory quality CPR in pigs, but not with quality simulating clinically reported CPR performance.

Animals↗

Determination of prognosis after cardiac arrest may be more difficult after introduction of therapeutic hypothermia.

A 50-year-old patient had status epilepticus and no adequate reactions nine days after prolonged out-of-hospital cardiac arrest. The cause of the arrest was acute myocardial infarction which was treated successfully with percutaneous cardiac intervention (PCI) and a stent placement. He was treated with therapeutic hypothermia (33 degrees C) for 24h and in intensive care with respiratory support for 42 days. One year later he has fully recovered and is back to normal life and academic work. The previously reported 100% prognosis of a poor neurological outcome in the presence of seizures 72 h post arrest may need to be re-examined after introduction of therapeutic hypothermia.

Heart Arrest↗

Effects of cardiopulmonary resuscitation on predictors of ventricular fibrillation defibrillation success during out-of-hospital cardiac arrest.

BACKGROUND: Early defibrillation is considered the most important factor for restoring spontaneous circulation in cardiac arrest patients with ventricular fibrillation. Recent studies have shown that, after prolonged ventricular fibrillation, the rates of return of spontaneous circulation (ROSC) and survival are improved if defibrillation is delayed so that CPR can be given first. To examine whether CPR improves myocardial readiness for defibrillation, we analyzed whether CPR causes changes in predictors of defibrillation success calculated from the ventricular fibrillation waveform. METHODS AND RESULTS: ECG recordings were retrieved for 105 patients from an original study of 200 patients receiving CPR or defibrillation first. Altogether, 267 CPR sequences from 77 patients were identified on which the effect of CPR could be evaluated. Five predictors of ROSC (spectral flatness measure, energy, centroid frequency, amplitude spectrum relationship, and estimated probability of ROSC) were determined from a spectral analysis of the ventricular fibrillation waveform immediately before and immediately after each of the 267 sequences. CPR increased spectral flatness measure, centroid frequency, and amplitude spectrum relationship (P<0.05, P<0.001, P<0.01). In an analysis of the effect of the duration of CPR, the probability of ROSC and amplitude spectrum relationship showed a positive change for CPR sequences lasting >3 minutes (P<0.001, P<0.05). CONCLUSIONS: During resuscitation from ventricular fibrillation, changes in the predictors calculated from the ventricular fibrillation waveform indicated a positive effect of CPR on the myocardium.

Cardiopulmonary Resuscitation↗

[Therapeutic hypothermia after cardiac arrest saves more lives!].

To treat patients suffering from cardiac arrest after restoration of spontaneous circulation has been difficult and discouraging, with a high mortality rate. Two independent studies have, however, shown that early treatment with hypothermia increases survival and protects from neurological sequelae after out-of-hospital cardiac arrest. Recently the International Liaison Committee on Resuscitation (ILCOR) has published an advisory statement recommending therapeutic hypothermia after out-of-hospital cardiac arrest. In this paper the issue is discussed and the therapy recommended.

Cardiopulmonary Resuscitation↗

Effects of interrupting precordial compressions on the calculated probability of defibrillation success during out-of-hospital cardiac arrest.

BACKGROUND: Cardiopulmonary resuscitation (CPR) creates artifacts on the ECG and, with automated defibrillators, a pause in CPR is mandatory during rhythm analysis. The rate of return of spontaneous circulation (ROSC) is reduced with increased duration of this hands-off interval in rats. We analyzed whether similar hands-off intervals in humans with ventricular fibrillation causes changes in the ECG predicting a lower probability of ROSC. METHODS AND RESULTS: The probability of ROSC after a shock was continually determined from ECG signal characteristics for up to 20 seconds of 634 such hands-off intervals in patients with ventricular fibrillation. In hands-off intervals with an initially high (40% to 100%) or median (25% to 40%) probability for ROSC, the probability was gradually reduced with time to a median of 8% to 11% after 20 seconds (P<0.001). In episodes with a low initial probability (0% to 25%; median, 5%), there was no further reduction with time. CONCLUSIONS: The interval between discontinuation of chest compressions and delivery of a shock should be kept as short as possible.

Artifacts↗

[New guidelines for basic and advanced resuscitation of adults and children].

We present the latest changes in the guidelines for resuscitation from the International Liaison Committee on Resuscitation (ILCOR). Defibrillation performed by non-medical personnel is more strongly endorsed than before. In unintubated patients the ventilation-to-compression ratio should always be 2:15. With a foreign body in the airway of an unconscious patient, compressions should be performed instead of the Heimlich manoeuvre. Amiodarone 300 mg intravenously is the first choice in refractory ventricular fibrillation or ventricular tachycardia in adults. Intubation of children is only recommended when performed by experienced personnel. The use of drugs is less recommended than previously; albumin is not recommended for the newly born.

Adult↗

Inspiratory impedance threshold valve during CPR.

The use of an inspiratory impedance threshold valve (ITV) during cardiopulmonary resuscitation (CPR) should reduce intrathoracic pressure during natural chest recoil or active chest decompression. This might in turn improve venous return and thereby organ blood flow. The haemodynamic effects during both standard CPR and active compression-decompression (ACD)-CPR with and without the ITV, therefore, were studied in a well-established porcine model with cross-over design. Sixteen pigs were randomised to one of four methods initially, changing the method every fifth minute during mechanical chest compression at 100 min(-1). Myocardial blood flow was doubled when the valve was added to standard CPR, median (q25-q75) 14 (3-47) versus 27 (9-51) ml min(-1) 100 g(-1) (P=0.001). ACD-CPR caused a similar increase, while adding the ITV to ACD-CPR only tended to increase myocardial blood flow (P=0.077). Varying the technique had no effect on cerebral, kidney or carotid blood flow, coronary perfusion pressure, expired CO(2) concentrations or blood gases. The valve is a promising new tool in CPR, but more independent studies of the device are needed.

Analysis of Variance↗