CPRIC: Consciousness During Cardiopulmonary Resuscitation - Between Science, Ethics and Emerging Protocols

CPRIC (CPR-Induced Consciousness) represents one of the most fascinating and at the same time unknown phenomena of emergency-urgency. While in other countries research on this topic is rapidly expanding, in Italy it is still talked about too little, despite the clinical, ethical and medico-legal implications being far from negligible.

What is CPRIC?

CPRIC refers to the appearance of signs of consciousness (eye opening, vocalizations, voluntary movements) during CPR without spontaneous return of circulation. It is important to distinguish this phenomenon from "post-arrest autoresuscitation" (Lazarus phenomenon), which occurs after the suspension of compressions.

Clinical manifestations go beyond the classic signs: we can also observe resistance to intubation maneuvers (trismus, biting on the tube) and attempts to remove the AED. These signs represent the most tangible manifestation of a phenomenon that challenges our traditional conceptions of consciousness during cardiac arrest.

The Numbers of the Phenomenon: A Reality More Common Than We Thought

According to international data, the reported incidence is 0.23 – 0.9% of resuscitations, although these values come from registries with a high risk of under-reporting. However, the discrepancy between the official incidence and field experience is significant: 48-59% of experienced professionals declare having observed at least one case.

This difference suggests that many episodes go unrecognized or undocumented, probably due to a lack of awareness of the phenomenon or difficulty in distinguishing voluntary movements from automatic reflexes. Associated factors include witnessed arrest, shockable rhythm, and, particularly interestingly, mechanical compressions (79% of Norwegian cases).

The association with mechanical devices is not accidental: these guarantee more constant and deep compressions, optimizing cerebral perfusion. The trend has been increasing in the last 6 years, probably due to the improvement in the quality of CPR and the spread of mechanical compression devices.

Pathophysiology: When the Brain "Wakes Up"

Understanding CPRIC requires a review of our understanding of cerebral perfusion during cardiac arrest. Effective chest compressions generate diastolic pressures that provide 20-40% of baseline cerebral flow, sufficient to activate partial cortical networks.

This data is revolutionary: it shows that the brain is not completely "turned off" during CPR, but maintains a level of metabolic activity compatible with consciousness. The critical threshold seems to be precisely that 20-40% of normal flow, a window that can open when compressions are particularly effective or when mechanical devices are used.

Monitoring: Tools to Recognize CPRIC

Recognizing CPRIC in real time is essential for appropriate management. Recommended monitoring, resulting from the synthesis of the most advanced international experiences, includes:

• ETCO₂ to assess the quality of compressions: values above 20 mmHg during CPR indicate effective perfusion

• NIRS (rSO₂) : oscillations >10% suggest "conscious" perfusion. Regional cerebral saturation becomes a real intra-arrest "traffic light"

• Reduced-channel EEG when available (multicenter trials ongoing)

The implementation of these monitoring systems represents the future of personalized CPR, allowing the intensity and modality of compressions to be adapted in real time based on the patient's brain response.

The Therapeutic Challenge: When CPR Meets Anesthesia

The management of CPRIC represents one of the most complex challenges of modern emergency, requiring skills ranging from resuscitation to anesthesia, from ethics to communication. Since there are no unified international guidelines yet, the protocols currently in use derive from the synthesis of best practices developed in centers of excellence worldwide.

Pharmacological Management: A Graduated Approach Based on International Experience

The pharmacological approach to CPRIC is based on a graded model that reflects the synthesis of the Norwegian, Canadian and Australian protocols, currently the most advanced in the world:

Level	Drugs	IV dose	When
Minimum	Midazolam + Fentanyl	1–2 mg + 25–50 µg	Gentle movements, cooperation
Moderate	Ketamine + Midazolam	0.5–1 mg/kg + 0.5–1 mg	Agitation that hinders CPR
Deep	Propofol or Etomidate	0.5–1 mg/kg / 0.2–0.3 mg/kg	Only with anesthetist/advanced team

The choice of level depends not only on the intensity of the signs of consciousness, but also on the competence of the team and the care setting. Ketamine emerges as the drug of first choice in most international protocols for its hemodynamic stability, but requires attention to hypersalivation that can complicate ventilation.

The Ethical Imperative: Never Paralyze Without Sedating

One of the clearest points that emerged from the international consensus is the absolute prohibition of paralyzing a conscious patient. This principle, shared by all the analyzed protocols, has deep ethical roots: paralysis in the presence of consciousness would constitute inhuman treatment according to the majority of ethicists.

Curarization is indicated only after deep sedation to facilitate rapid intubation (rocuronium 1 mg/kg), following a sequence that respects the dignity of the patient. The ILCOR 2023 consensus, while acknowledging the lack of robust evidence, recommends the development of flexible local protocols that take into account this ethical priority.

The Operating Protocol: Synthesis of World Best Practices

The protocol proposed here represents a synthesis of the operative procedures developed by the most advanced centres, in particular the Norwegian pre-hospital experience and the Canadian protocols of Ontario. It is a modified RSI that takes into account the peculiarities of the CPRIC:

1. Early recognition of CPRIC while maintaining continuity of compressions

2. Immediate sedation (ketamine ± midazolam or etomidate) with compression interruption limited to <10 seconds

3. Objective verification of loss of consciousness before proceeding

4. Paralysis and rapid intubation followed by immediate resumption of compressions

5. Continuous ETCO₂ + NIRS monitoring with detailed time and dose documentation

This apparently simple sequence requires perfect team coordination and specific training that is still largely absent in Italy.

Psychological Impact: An Often Overlooked Dimension

The experience of consciousness during CPR leaves indelible marks on both patients and healthcare workers. Follow-up studies show that survivors with memory of the event have an increased incidence of anxiety, depression, or PTSD.

In parallel, healthcare personnel who witness CPRIC episodes often report a significant emotional impact, due to the difficulty of managing a conscious patient during such an invasive procedure. For this reason, the most advanced protocols include specific debriefing programs and dedicated simulations that improve "real-time" communication with the conscious patient.

The communication dimension becomes crucial: knowing how to reassure a patient who is experiencing his own resuscitation requires skills that go far beyond traditional medical technique.

Medico-Legal Aspects: Navigating Uncharted Waters

From a medico-legal point of view, CPRIC opens up complex scenarios. Consent is presumed for "best interest", but the management of a conscious patient during CPR requires meticulous documentation. Paralysis without sedation would constitute inhumane treatment according to the majority of ethicists.

Documentation is therefore crucial: reasons for therapeutic choices, drugs used, doses administered and physiological responses must be accurately recorded for possible audits or disputes. In the absence of national guidelines, this documentation often represents the only legal protection for operators.

The International Panorama: Italy at the Bottom of the Class

While Italy remains substantially absent from the international scientific debate, other countries are leading the development of knowledge and protocols:

Norway conducted the first systematic national survey involving pre-hospital anesthetists, documenting 116 cases with 79% associated with mechanical compression. Their standardized ketamine sedation protocol has become a reference model.

The UK has invested in training with a qualitative study of 465 paramedics, identifying significant training gaps. The Resuscitation Council UK is developing the first dedicated national guidelines.

Australia coordinates the most ambitious international project with the OHCA Victoria registry and a Delphi study involving global experts to define common standards.

Canada has developed specific protocols in Ontario with a particular focus on ketamine/fentanyl, supported by a data collection system in hospital-based registries.

The United States is leading the technological research with multicenter EEG/NIRS trials coordinated by NYU's Parnia Lab, while the AHA has announced the arrival of specific guidelines post-2026.

Even Germany , traditionally more conservative, has initiated systematic analyses of the national registry identifying an incidence of 0.23% in 23,011 cases of OHCA.

Research Gaps and Future Prospects

The international research agenda is ambitious and well defined:

1. International prospective registries to estimate real incidence and long-term neurological outcomes

2. Comparative pharmacological trials to identify optimal sedative-analgesic protocols during CPR

3. Validation of NIRS + EEG algorithms for automatic "live" consciousness detection

4. Cost-effectiveness studies comparing out-of-hospital RSI vs. supraglottic devices in CPRIC

5. Elaboration of a shared ethical-legal consensus for the ERC/AHA/ILCOR 2027 cycle

These priorities reflect the maturity reached by international research, which has moved beyond the anecdotal stage to enter that of evidence-based medicine.

Key Messages for Clinical Practice

The synthesis of the international experience leads to six key messages for clinical practice:

1. CPRIC is rare but real : consciousness during CPR indicates effective cerebral perfusion and should not be ignored

2. Sedating before paralyzing is essential : it represents an ethical imperative even before a clinical one.

3. NIRS/ETCO₂ monitoring supports diagnosis and guides sedation in real time

4. Mechanical devices increase the likelihood of CPRIC : teams using them need to be specifically trained

5. Attention to post-arrest psychological care must extend to both patients and responders

6. International registries and unified guidelines urgently needed by next ERC/AHA cycle

Conclusions: It's Time to Close the Gap

The lack of international guidelines has led to the development of heterogeneous local protocols, but this can no longer be an excuse for inaction, especially in Italy where the issue is virtually ignored. CPRIC represents a bridge between resuscitation, anesthesia and clinical ethics that requires a coordinated multidisciplinary response.

The recommendations presented in this article are not the result of theoretical speculation, but represent the critical synthesis of the most advanced protocols currently in use in centers of excellence worldwide. They are the result of years of clinical experience, systematic research and international comparison.

In Italy it is urgent to start a serious discussion on this topic, involving the scientific societies of the sector (SIAARTI, SIMEU, SIS 118) and promoting specific training. Consciousness during CPR is not science fiction: it is a clinical reality that deserves attention, respect and professional competence.

Our country cannot afford to be left behind on a topic that touches such fundamental aspects of emergency medicine. It is time to overcome scientific provincialism and engage with international best practices.

Silence on this issue is no longer justifiable. It is time to act.

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