Table 4. 2020 Adult Guidelines Critical Knowledge Gaps

Table 4. 2020 Adult Guidelines Critical Knowledge Gaps
Sequence of Resuscitation
Initiation of resuscitation What are optimal strategies to enhance lay rescuer performance of CPR?
Metrics for high-quality CPR What is optimal for the CPR duty cycle (the proportion of time spent in compression relative to the total time of the compression-plus-decompression cycle)?
Metrics for high-quality CPR What is the validity and reliability of ETCO2 in nonintubated patients?
Metrics for high-quality CPR For patients with an arterial line in place, does targeting CPR to a particular blood pressure improve outcomes?
Metrics for high-quality CPR How does integrated team performance, as opposed to performance on individual resuscitation skills, affect resuscitation outcomes?
Defibrillation Is there an ideal time in the CPR cycle for defibrillator charging?
Defibrillation Can artifact-filtering algorithms for analysis of ECG rhythms during CPR in a real-time clinical setting decrease pauses in chest compressions and improve outcomes?
Defibrillation Does preshock waveform analysis lead to improved outcome?
Defibrillation Do double sequential defibrillation and/or alternative defibrillator pad positioning affect outcome in cardiac arrest with shockable rhythm?
Vascular access Is the IO route of drug administration safe and efficacious in cardiac arrest, and does efficacy vary by IO site?
Vasopressor medications during cardiac arrest Does epinephrine, when administered early after cardiac arrest, improve survival with favorable neurological outcome?
Nonvasopressor medications during cardiac arrest Do antiarrhythmic drugs, when given in combination for cardiac arrest, improve outcomes from cardiac arrest with shockable rhythm?
Nonvasopressor medications during cardiac arrest Do prophylactic antiarrhythmic medications on ROSC after successful defibrillation decrease arrhythmia recurrence and improve outcome?
Nonvasopressor medications during cardiac arrest Do steroids improve shock or other outcomes in patients who remain hypotensive after ROSC?
Adjuncts to CPR Does the use of point-of-care cardiac ultrasound during cardiac arrest improve outcomes?
Adjuncts to CPR Is targeting a specific ETCO2 value during CPR beneficial, and what degree of rise in ETCO2 indicates ROSC?
Termination of resuscitation Can ETCO2 be used for intra-arrest prognostication, in combination with other metrics?
Termination of resuscitation Can point-of-care cardiac ultrasound, in conjunction with other factors, inform termination of resuscitation?
Advanced Techniques and Devices for Resuscitation
Advanced airway placement What is the optimal approach to advanced airway management for IHCA?
Advanced airway placement There is a need for further research specifically on the interface between patient factors and the experience, training, tools, and skills of the provider when choosing an approach to airway management.
Advanced airway placement What is the specific type, amount, and interval between airway management training experiences to maintain proficiency?
Alternative CPR techniques and devices Which populations are most likely to benefit from ECPR?
Specific Arrhythmia Management
Atrial fibrillation or flutter with rapid ventricular response What is the optimal energy needed for cardioversion of atrial fibrillation and atrial flutter?
Bradycardia What is the optimal approach, vasopressor or transcutaneous pacing, in managing symptomatic bradycardia?
Care After ROSC
Postresuscitation care Does avoidance of hyperoxia in the postarrest period lead to improved outcomes?
Postresuscitation care What is the effect of hypocarbia or hypercarbia on outcome after cardiac arrest?
Postresuscitation care Does the treatment of nonconvulsive seizures, common in postarrest patients, improve patient outcomes?
Postresuscitation care What are the optimal pharmacological treatment regimens for the management of postarrest seizures?
Postresuscitation care Do neuroprotective agents improve favorable neurological outcome after arrest?
Postresuscitation care What is the most efficacious management approach for postarrest cardiogenic shock, including pharmacological, catheter intervention, or implantable device?
Postresuscitation care Is there a role for prophylactic antiarrhythmics after ROSC?
Targeted temperature management Does targeted temperature management, compared to strict normothermia, improve outcomes?
Targeted temperature management What is the optimal temperature goal for targeted temperature management?
Targeted temperature management What is the optimal duration for targeted temperature management before rewarming?
Targeted temperature management What is the best approach to rewarming postarrest patients after treatment with targeted temperature management?
PCI after cardiac arrest Does emergent PCI for patients with ROSC after VF/VT cardiac arrest and no STEMI but with signs of shock or electric instability improve outcomes?
Neuroprognostication What is the interrater agreement for physical examination findings such as pupillary light reflex, corneal reflex, and myoclonus/status myoclonus?
Neuroprognostication Can we identify consistent NSE and S100B thresholds for predicting poor neurological outcome after cardiac arrest?
Neuroprognostication Are NSE and S100B helpful when checked later than 72 h after ROSC?
Neuroprognostication Are glial fibrillary acidic protein, serum tau protein, and neurofilament light chain valuable for neuroprognostication?
Neuroprognostication More uniform definitions for status epilepticus, malignant EEG patterns, and other EEG patterns are needed to be able to compare prognostic values across studies.
Neuroprognostication What is the optimal timing for head CT for prognostication?
Neuroprognostication Is there a consistent threshold value for prognostication for GWR or ADC?
Neuroprognostication Standardization of methods for quantifying GWR and ADC would be useful.
Recovery and survivorship after cardiac arrest What do survivor-derived outcome measures of the impact of cardiac arrest survival look like, and how do they differ from current generic or clinician-derived measures?
Recovery and survivorship after cardiac arrest Are there in-hospital interventions that can reduce or prevent physical impairment after cardiac arrest?
Recovery and survivorship after cardiac arrest Which patients develop affective/psychological disorders of well-being after cardiac arrest, and are they treatable/preventable/recoverable?
Recovery and survivorship after cardiac arrest Does hospital-based protocolized discharge planning for cardiac arrest survivors improve access to/ referral to rehabilitation services or patient outcomes?
Special Circumstances of Resuscitation
Accidental hypothermia What combination of features can identify patients with no chance of survival, even if rewarmed?
Accidental hypothermia Should severely hypothermic patients receive intubation and mechanical ventilation or simply warm humidified oxygen?
Accidental hypothermia Should severely hypothermic patients in VF who fail an initial defibrillation attempt receive additional defibrillation?
Accidental hypothermia Should severely hypothermic patients in cardiac arrest receive epinephrine or other resuscitation medications? If so, what dose and schedule should be used?
Drowning In what situations is attempted resuscitation of the drowning victim futile?
Drowning How long after mild drowning events should patients be observed for late-onset respiratory effects?
Electrolyte abnormalities What is the optimal treatment for hyperkalemia with life-threatening arrhythmia or cardiac arrest?
Opioid overdose What is the minimum safe observation period after reversal of respiratory depression from opioid overdose with naloxone? Does this vary based on the opioid involved?
Opioid overdose Is there benefit to naloxone administration in patients with opioid-associated cardiac arrest who are receiving CPR with ventilation?
Opioid overdose What is the ideal initial dose of naloxone in a setting where fentanyl and fentanyl analogues are responsible for a large proportion of opioid overdose?
Opioid overdose In cases of suspected opioid overdose managed by a non–healthcare provider who is not capable of reliably checking a pulse, is initiation of CPR beneficial?
Pregnancy What is the ideal timing of PMCD for a pregnant woman in cardiac arrest?
Pulmonary embolism Which patients with cardiac arrest due to “suspected” pulmonary embolism benefit from emergency thrombolysis during resuscitation?
Toxicity: β-adrenergic blockers and calcium channel blockers What is the ideal sequencing of modalities (traditional vasopressors, calcium, glucagon, high-dose insulin) for refractory shock due to β-adrenergic blocker or calcium channel blocker overdose?
Toxicity: local anesthetics What are the ideal dose and formulation of IV lipid emulsion therapy?
Toxicity: carbon monoxide, digoxin, and cyanide Which patients with cyanide poisoning benefit from antidotal therapy?
Toxicity: carbon monoxide, digoxin, and cyanide Does sodium thiosulfate provide additional benefit to patients with cyanide poisoning who are treated with hydroxocobalamin?

ADC indicates apparent diffusion coefficient; CPR, cardiopulmonary resuscitation; CT, computed tomography; ECG, electrocardiogram; ECPR, extracorporeal cardiopulmonary resuscitation; EEG, electroencephalogram; ETCO2, end-tidal carbon dioxide; GWR, gray-white ratio; IHCA, in-hospital cardiac arrest; IO, intraosseous; IV, intravenous; NSE, neuron-specific enolase; PCI, percutaneous coronary intervention; PMCD, perimortem cesarean delivery; ROSC, return of spontaneous circulation; S100B, S100 calcium binding protein; STEMI, ST-segment elevation myocardial infarction; and VF, ventricular fibrillation.