ConsCIOUS2 Study of the Isolated Forearm Technique Commands

ConsCIOUS2: A Prospective Study of the Isolated Forearm Technique Commands, Long-term Sequelae and Electroencephalograph Correlates Following Laryngoscopy and Intubation in Patients 18 - 40 Years of Age

Rambam Health Care Campus, University of Groningen, Centre Hospitalier Regional de la Citadelle, RWTH Aachen University, University of Pennsylvania, Ludwig-Maximilians - University of Munich, Cornell University, Cairns Hospital, Auckland District Health Board, Waikato Hospital

ConsCIOUS-2 is a multi-site study exploring the cognitive state of the Isolated Forearm Test (IFT) responder while under anesthetic.

500 participants between the ages of 18-40 who will be undergoing surgery requiring general anesthetic will be recruited for this study. This study will use the Isolated Forearm Test (IFT) to identify patients at risk of anesthesia awareness. In the IFT, induction of anesthesia is followed by inflation of a cuff on the dominant arm before neuromuscular blockade (paralysis) is induced. The cuff prevents paralysis of the hand allowing the patient to communicate to an observer through predefined hand movements, typically following a command like: "Mrs. Jones, if you can hear me, squeeze my hand". Participants will thus be asked to follow a series of commands intraoperatively to assess awareness. Routinely recorded clinical data will be collected to frame the observations about IFT responsiveness, and non-invasive EEG data will also be collected to provide information about the "brain state" of the patients. Patient reported confusion and objectively measured confusion using the Nurse Based Delirium Screening Tool (NuDesc) will be collected post operatively. Finally, participants will be contacted 24 hours and 7 days following their operation to complete an anesthesia satisfaction questionnaire.

Participants will be fitted with and IFT cuff and randomized to command list A intra-operatively to assess awareness.

Participants will be fitted with and IFT cuff and randomized to command list B intra-operatively to assess awareness.

Participants will be fitted with and IFT cuff and randomized to command list C intra-operatively to assess awareness.

Participants will be fitted with and IFT cuff and randomized to command list D intra-operatively to assess awareness.

Identify the incidence of IFT responsiveness following intubation assessed by hand squeezing response following a randomized command sequence to assess for non-specific responses.

Test the association between intra-operative IFT responsiveness and patient reported confusion following emergence from anesthesia and objectively assessed confusion using the NuDesc

Identify the incidence of implicit memory in post anesthesia care unit and anesthesia awareness with recall 24 hours and 7 days postoperatively using the structured Modified Brice questionnaire

Identify changes in patient satisfaction associated with IFT responsiveness via a patient satisfaction questionnaire administered 24 hours and 7 days postoperatively.

Inclusion Criteria: Age 18-40 years English (or local language) competent Informed consent obtained Patients clinically requiring general anesthesia and intubation Able to safely follow the IFT commands when awake and prior to their operation, per discretion of the PI. Exclusion Criteria: Age < 18 years old, >40 years old Unable or unwilling to sign consent Unable to undergo postoperative questions Contraindication to IFT test such as unable to have tourniquet on arm for the IFT (e.g. lymphedema or operative site), rapid sequence inductions and requiring paralysis for laryngoscopy and intubation, per discretion of the PI.