Physiologic Monitoring During CPR

• Physiologic monitoring during CPR aims to optimize CPR quality and recognize inadequacies early
• Consider interventions like ECPR or PCI.
• Clinicians to consider more invasive measures during CPR if it's inadequate and survival with good neurologic function is possible.
• Traditional monitoring includes ECG evaluation and carotid or femoral artery pulse palpation.
• Electrocardiographic monitoring indicates electrical activity but not mechanical heart activity.
• Coronary perfusion pressure (CPP) relies on the aortic diastolic pressure minus the right atrial diastolic pressure during CPR.
• Traditional monitoring modalities are not reliable in assessing CPR effectiveness.
• PETCO2 monitoring can indicate cardiac output during CPR and correlates with CPP and cerebral perfusion pressure.
• A PETCO2 of ≥10 mm Hg is needed; values <10 mm Hg indicates inadequate CPR quality.
• Monitor PETCO2 after ROSC to check endotracheal tube placement and guide minute ventilation to avoid hyperventilation.
• Central venous oxygen saturation (Scvo2) monitors changes in oxygen delivery and can indicate resuscitation adequacy.
• An Scvo2 that fails to reach 40% during CPR has a high negative predictive value for ROSC.
• Echocardiography helps diagnose the causes of pulseless electrical activity as well as assesses myocardial dysfunction post-arrest.
• Underlying causes of pulseless electrical activity are also diagnosed with echocardiography.
• Echocardiography is essential in cardiac contractility assessment.
• Echocardiography is a key tool for myocardial dysfunction evaluation
• A variety of echocardiography techniques are available.
• Interpretation of echocardiogram results is crucial for diagnosis.
• ECPR should be initiated within 60 minutes of cardiac arrest onset for maximum effectiveness.
• ECPR complications include coagulopathy, hemorrhage, limb ischemia, and stroke.
• Blood gas findings during CPR typically show venous respiratory acidosis and arterial respiratory alkalosis.
• A minimum CPP of 15 mm Hg is needed for ROSC if initial defibrillation attempts fail.
• Continuing failure to reach a CPP of 15 mm Hg can indicate unsuccessful CPR.
• After ROSC, focus on rapidly diagnosing the arrest cause and managing global ischemia complications.
• The targeted temperature range in hypothermic targeted temperature management (HTTM) is 32° to 36°C (89.6° to 96.8°F).
• Target temperature should be achieved in HTTM after cardiac arrest in less than 2 hours, up to a median of 8 hours.
• Complications during HTTM include shivering, which can be mitigated with sedation.
• The maximum lorazepam dose for seizures in post-cardiac arrest patients is 0.1 mg/kg/dose, up to 4 mg.
• Treat persistent seizures lasting >5 minutes with anti-seizure medications.
• In comatose patients after cardiac arrest, perform a 12-lead ECG as soon as feasible after ROSC.
• Post-cardiac arrest patients with ST segment elevation should undergo prompt percutaneous coronary intervention (PCI).
• Angiography and PCI should not be delayed in STEMI cases; neurologic status should not delay immediate intervention.
• Consider dual therapy with aspirin and a P2Y12 inhibitor, such as ticagrelor, for post-cardiac arrest patients with suspected ACS if no contraindications.
• The goal is to maintain an arterial oxyhemoglobin saturation of at least 94% during CPR.
• Hyperoxia can worsen brain injury after cardiac arrest.
• Continuously monitor serum lactate levels and mixed venous oxygen saturation to assess tissue oxygen delivery.
• Elevated lactate coupled with low mixed venous oxygen saturation (SVO2) indicates inadequate oxygen delivery suggesting insufficient oxygen delivery.
• Bed-side ultrasound can assess cardiac contractility and guide volume expansion without causing pulmonary edema.
• Monitor Scvo2 and lactate levels serially to guide therapy and assess response.
• Optimize oxygen delivery if Scvo2 remains low despite resuscitation efforts.
• Dobutamine should be used when cardiac output is insufficient after adequate fluid volume.
• Monitor hemodynamic management through changes in lactate levels and Scvo2.
• Persistently elevated lactate levels indicate inadequate oxygen delivery and potential tissue hypoxia.
• An increase in Scvo2 coupled with a decrease in lactate levels indicates improved oxygen delivery and better tissue perfusion.
• Echocardiography helps distinguish between various causes of cardiac arrest and assess ventricular function.
• Immediate angiography may improve survival rates and outcomes when STEMI is present.
• Persistent high heart rates may indicate inadequate perfusion; further evaluation is needed.
• The standard compression-to-ventilation ratio in pediatric resuscitation is 30:2 for healthcare providers until an advanced airway is placed.
• Calculate and titrate inspired oxygen to maintain desired oxygen saturation levels while avoiding hyperoxia.
• ST segment elevation indicating a STEMI requires urgent PCI.
• Waveform capnography provides real-time feedback on ventilation and cardiac output.
• Regular intermittent Scvo2 measurements can provide useful data if continuous monitoring isn't feasible.
• Echocardiography can be used to visualize the heart during CPR to assess compression technique.
• ECPR-associated risks include high resource demands, coagulopathy, hemorrhage, and ischemic injuries.
• Ensure adequate volume status to optimize oxygen delivery before administering high-dose vasopressors.
• Cooling efforts should begin in the ED as soon as feasible after achieving ROSC.
• Shivering during HTTM may impede cooling; manage pharmacologically.
• Dual antiplatelet therapy enhances platelet inhibition and may improve outcomes in ACS scenarios.
• Typical blood gas levels during CPR are arterial respiratory alkalosis and venous respiratory acidosis due to poor perfusion.
• Maintain a consistent target temperature during heat management while monitoring for any fluctuations.
• Routine immediate angiography and PCI may not improve outcomes in cases lacking clinical suspicion of ACS, where delayed angiography could be considered.
• Assessing the heart rhythm is critical to determine if defibrillation or other measures are appropriate.
• Evaluate for acute coronary syndromes using ECG and clinical guidelines after achieving ROSC.
• Titration to maintain appropriate oxygen levels can prevent hyperoxia and associated risks.
• Meeting physiological parameters assessed through PETCO2 and Scvo2 monitoring defines adequate cardiac output during CPR.
• An intra-aortic balloon pump may be necessary in severe hemodynamic instability to augment cardiac output.
• Continuous training and assessment methods, including CPR drills and simulations, can improve outcomes related to CPR.
• Early goal-directed therapy refers to timely interventions based on specific clinical markers to optimize patient outcomes post-arrest.
• Echocardiography is most effectively used to visualize cardiac function during CPR.
• Sedatives or neuromuscular blockers prevent shivering and improve temperature control during HTTM.
• High-quality CPR correlates positively with survival rates and neurological function post-arrest.
• Patients with significant co-morbid conditions should receive tailored interventions consistent with their overall health status.
• Increased lactate levels and decreased SVO2 alongside hemodynamic instability indicates inadequate oxygen delivery.
• Ventilator settings, particularly the fraction of inspired oxygen and tidal volume, significantly impact CPV.
• Assess systemic blood pressure and organ perfusion through vital sign measurements to determine vasopressor needs.
• Initiate CPR immediately and perform compressions until an airway is established, as per guidelines.
• Elevated CO2 levels can indicate poor ventilation and insufficient oxygen delivery.
• Ventricular fibrillation and pulseless ventricular tachycardia require rapid defibrillation.
• Continuous arterial pressure measurements provide real-time assessment of hemodynamics and guide resuscitative efforts.
• Regular feedback and life support training sessions for all healthcare staff involved in resuscitation help maintain the efficacy of CPR.
• Establish protocols and multi-disciplinary teams ahead of time to ensure smooth ECPR integration.
• Advanced monitoring techniques such as PETCO2 and Scvo2 provide critical insights during resuscitation.
• Oxygen debt is typically managed through careful volume resuscitation and appropriate vasopressor use to optimize delivery.
• Low Scvo2 readings suggest inadequate oxygen delivery requiring immediate intervention.
• Increase inspired oxygen during CPR if oxygen saturation levels fall below the target range of 94% in the case of normothermia.
• Initiate hyperkalemia treatment per clinical guidelines, considering both pharmacological and mechanical interventions.
• Comprehensive assessments and immediate treatment based on the underlying cause of cardiac arrest should be prioritized after ROSC.
• In cases of severe heart failure or inappropriate hemodynamic responses, consider ECMO or IABP.
• Immediate pacing or pharmacotherapy is crucial to maintain adequate heart rate and perfusion in symptomatic bradycardia management.
• Discussions with family and clear evaluation of the patient’s wishes, prognosis, and clinical status guide end-of-life care decisions.
• Continuous assessment during the cooling phase is essential to optimize neuroprotective strategies.
• Prolonged high doses of vasopressors can lead to severe tissue perfusion issues and corresponding lactic acidosis.
• Increases in PETCO2 and normalization of hemodynamic parameters signify successful resuscitation during CPR intervention.
• Hemodynamic instability and simultaneous management of multiple life-supporting measures complicate the monitoring process during CPR.
• Intracranial pressure monitoring should be considered for patients showing neurological signs post-ROSC.
• Assess for underlying cardiac causes, including myocardial infarction, that may require urgent intervention when managing cardiac arrest patients.
• A rise in lactate serum levels post-ROSC typically reflects inadequate Do2 and the potential for subsequent organ dysfunction.
• Pre-existing co-morbidities can complicate treatment plans and necessitate more tailored approaches for patient care.
• Monitor diabetic patients or those with suspected adrenal insufficiency closely for potential hypoglycemia post-cardiac arrest.
• Inadequate oxygen delivery requires interventions to improve both perfusion and oxygenation.
• Serial imaging and laboratory assessments help clarify potential underlying causes of cardiac arrest.
• Reassess vital signs every 5-15 minutes during the initial phase through continuous monitoring.
• Late strategies aim to prevent multi-organ failure and to facilitate rehabilitation options for survivors.
• Ensure adequate ventilation and avoid hyperventilation to prevent acute lung injury during mechanical ventilation.
• Involuntary thermogenesis can occur, impacting temperature management strategies during hypothermic therapy.
• Continuous monitoring of blood pressure and urine output indicates systemic perfusion.
• Blood pressure maintenance, organ function, and adequate urine output demonstrate cardiovascular stability.
• Confirm waveform signals or blood return proves successful central venous access before further actions.
• Initiate early cardiology consultations if ongoing cardiovascular instability is apparent.
• Coordination among specialties enables comprehensive strategies and management for improving survival rates through a multidisciplinary team.
• Normothermia prevents complications associated with hyperthermia, promoting optimal recovery conditions.
• Consistent Glasgow Coma Scale evaluations provide insight into neurological status.
• Calibrate medications to achieve an effective state while allowing sufficient neurological assessment.
• Deterioration in hemodynamic parameters necessitates immediate reassessment and intervention during CPR.
• Neurological function at the of ROSC and the etiological mechanism behind the arrest are crucial for determining prognosis.
• Clear protocols and role definitions optimize CPR quality while balancing clinician stress.
• Patients with altered states of consciousness or those who have shown seizure activity during monitoring may require continuous EEG monitoring.
• Comorbidities must be assessed and managed concurrently to achieve the best outcomes in cardiac arrest patients.
• An ECG is crucial for identifying any acute coronary syndromes present in the patient’s condition following ROSC.
• Electrolytes imbalances are essential for evaluation during CPR
• Collaboration and ensures seamless care transitions for post-arrest patients is achieved through ongoing communication
• Bedside ultrasound and continuous arterial pressure monitoring can guide care effectively which are non-invasive.
• Fluid overload leading to pulmonary complications should be closely monitored during fluid resuscitation.
• Stabilization of clinical status and basic cardiovascular metrics can dictate the urgency for transferring patients to higher levels of care.
• Documentation provides crucial legal and clinical accountability for care provided.
• The emphasis on collaborative multidisciplinary protocols and evidence-based decision-making has influenced current approaches to post-cardiac arrest care.
• Monitoring dynamic changes in lactate and Scvo2 levels provides insights into tissue perfusion status, the interplay of oxygen delivery and consumption .
• Ejection fraction (EF) is a measurement of overall cardiac volume.
• EF may not reflect regional cardiac dysfunction.
• Understanding normal ejection fraction is beneficial.
• Information about satisfactory EF during CPR is beneficial.
• Understanding how EF is normally measured is beneficial.
• Understanding how EF is measured emergently during CPR is beneficial.
• Post-cardiac arrest ventilator settings, specifically FiO2 and tidal volume, require careful management, as they directly impact cerebral perfusion pressure.

FiO2 Adjustment Strategies

• The fraction of inspired oxygen (FiO2) is a critical ventilator setting that must be carefully adjusted.
• Management of FiO2 is essential to optimize patient care post-cardiac arrest.

Tidal Volume Considerations

• Tidal volume is another key ventilator setting that affects cerebral perfusion pressure.
• Proper tidal volume settings are necessary to improve patient outcomes after cardiac arrest.

Cerebral Perfusion Pressure Management

• Optimizing ventilator settings helps maintain adequate cerebral perfusion pressure.

Intraaortic Balloon Pumps (IABP)

• Used for temporary circulatory support in heart failure or cardiogenic shock.
• Can be used in patients awaiting heart transplant.
• Helps stabilize patients before or after cardiac surgery.
• Supports patients experiencing unstable angina.
• Assists patients during high-risk percutaneous coronary interventions.

Risks and Complications of IABP

• Limb ischemia is a major risk due to arterial occlusion.
• Bleeding can occur at the insertion site.
• Infection may develop, requiring antibiotic treatment or device removal.
• Thrombocytopenia (low platelet count) can occur.
• Balloon rupture can lead to gas embolism.
• Aortic dissection is a rare but severe complication.
• Migration of the balloon can obstruct major arteries.

Benefits of IABP Therapy

• Reduces afterload, easing the workload on the heart.
• Increases coronary blood flow, improving oxygen supply to the heart muscle.
• Enhances cardiac output, improving overall circulation.
• Lowers myocardial oxygen demand.
• Stabilizes hemodynamics in critically ill patients.

IABP Insertion Technique

• Accessed via the femoral, axillary, or rarely the subclavian artery.
• A guidewire is advanced into the aorta.
• The balloon catheter is advanced over the guidewire.
• Positioned in the descending aorta, distal to the left subclavian artery and proximal to the renal arteries.
• Correct placement is confirmed by fluoroscopy or x-ray.
• The balloon is inflated during diastole and deflated before systole, timed with the ECG.

Patient Monitoring During IABP Use

• Continuous ECG monitoring ensures proper balloon timing.
• Frequent blood pressure monitoring assesses hemodynamic stability.
• Regular assessment of peripheral pulses detects signs of ischemia.
• Urine output monitoring ensures adequate renal perfusion.
• ACT and platelet levels should be checked regularly.
• Regular checks of the insertion site detect bleeding or infection.

Management of Shivering During Targeted Temperature Management (TTM)

• When initial sedation is inadequate, deepen sedation with propofol or dexmedetomidine.

Propofol Dosing

• A loading dose of 1-2 mg/kg IV bolus can be used for rapid sedation.
• Maintain with continuous infusion of 5-50 mcg/kg/min, adjust based on sedation level.
• Higher rates (15-50 mcg/kg/min) may be needed for shivering during TTM.
• Propofol has a rapid onset and short duration.
• Monitor blood pressure and heart rate due to risk of hypotension, especially at higher doses.

Dexmedetomidine Dosing

• Administer a loading dose of 0.5-1 mcg/kg over 10-20 minutes.
• Follow with a maintenance infusion titrated between 0.2-1.5 mcg/kg/hour.
• Dosing at the higher end (1-1.5 mcg/kg/hour) may be considered for shivering during TTM.
• Dexmedetomidine provides sedation without respiratory depression.
• Monitor for bradycardia and hypotension.

Conclusion for Managing Shivering

• Consider propofol infusion at 15-50 mcg/kg/min or dexmedetomidine at 0.5-1.5 mcg/kg/hour.
• Close hemodynamic monitoring is critical due to potential side effects.

Global Longitudinal Strain (GLS)

• GLS measures myocardial deformation during the cardiac cycle.
• It reflects the percentage change in myocardial fiber length from end-diastole to systole.
• Expressed as a negative percentage, with more negative values indicating greater contraction.
• GLS is a valuable tool for assessing myocardial function and can detect subtle abnormalities before changes in ejection fraction.

Strain Imaging Analysis

• Strain imaging, including GLS measurement, is performed using speckle tracking echocardiography (STE).
• STE is a non-invasive technique that analyzes the motion of acoustic markers ("speckles") within the myocardium.
• Speckles are natural patterns in the ultrasound image.
• The software tracks the movement of speckles frame by frame.
• The software calculates myocardial displacement and deformation based on speckle movement.
• GLS is derived by averaging longitudinal strain values from multiple segments of the left ventricle (LV).

Clinical Measurement of GLS

• Image Acquisition: Standard 2D grayscale echocardiographic images are acquired from apical views.
• High frame rates (50-80 frames per second) are essential for accurate speckle tracking.
• Image quality is crucial for accurate strain measurements.
• Software Analysis: Acquired images are analyzed using dedicated speckle tracking software.
• The software automatically identifies and tracks speckles within the myocardium.
• Users typically define the endocardial border, and the software automatically traces the epicardial border; manual adjustments may be needed.
• The software calculates strain values for each segment of the LV.
• GLS Calculation: The software averages the peak systolic longitudinal strain values from all segments to derive the GLS value.
• The GLS value is typically displayed as a negative percentage (e.g., -20%).

Factors Affecting GLS Measurement

• Image Quality: Poor image quality can lead to inaccurate speckle tracking.
• Heart Rate: High heart rates can affect the accuracy of strain measurements.
• Arrhythmias: Irregular heart rhythms can confound strain analysis.
• Load Conditions: GLS can be influenced by preload and afterload.
• Vendor-Specific Software: Different software packages may yield slightly different GLS values. It is important to use the same software for serial measurements.

Normal Values and Interpretation

• Normal GLS values typically range from -18% to -22%.
• Specific normal range can vary slightly depending on the software and the patient population.
• Less negative GLS values (e.g., -10%) indicate impaired myocardial deformation and reduced contractility.
• More negative GLS values may be seen in conditions with hyperdynamic left ventricular function.
• Changes in GLS over time can indicate disease progression or response to therapy.

Clinical Significance of GLS

• GLS is a sensitive marker of myocardial dysfunction, often detecting abnormalities before changes in ejection fraction.
• It provides incremental prognostic information beyond traditional echocardiographic parameters.
• GLS is useful for risk stratification in various cardiovascular conditions.

Applications in Heart Disease

• Ischemic Heart Disease: GLS can detect subtle myocardial ischemia and infarction, even in patients with normal ejection fraction.
• It can help identify the location and extent of myocardial damage.
• GLS can be used to assess the effectiveness of revascularization strategies.
• Heart Failure: GLS is impaired in both heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF).
• It can help differentiate between different types of heart failure.
• GLS is a predictor of adverse outcomes in heart failure patients.
• Cardiomyopathies: GLS is useful for diagnosing and monitoring various cardiomyopathies, including hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and infiltrative cardiomyopathies (e.g., amyloidosis).
• Different cardiomyopathies have characteristic patterns of strain abnormalities.
• Valvular Heart Disease: GLS can detect early myocardial dysfunction in patients with valvular stenosis or regurgitation.
• It can help guide the timing of valve intervention.
• Cardiotoxicity: GLS is a sensitive marker of chemotherapy-induced cardiotoxicity.
• It can be used to monitor patients undergoing cardiotoxic cancer therapies and detect early signs of myocardial damage.

Echocardiography Techniques

• 2D Speckle Tracking Echocardiography (STE) is the primary technique for measuring GLS.
• It relies on tracking the movement of speckles within 2D echocardiographic images.
• It provides segmental and global strain values.
• 3D Speckle Tracking Echocardiography is an advanced technique that analyzes myocardial deformation in three dimensions.
• It provides a more comprehensive assessment of myocardial function compared to 2D STE.
• It is less widely available than 2D STE and requires specialized equipment and software.
• Contrast Echocardiography: The use of contrast agents can improve endocardial border definition and enhance speckle tracking, particularly in patients with poor image quality.
• Stress Echocardiography: GLS can be measured during stress echocardiography (e.g., exercise or dobutamine stress) to assess myocardial function under stress conditions.
• This can help detect inducible ischemia or other abnormalities that may not be apparent at rest.