Postoperative Cognitive Dysfunction (POCD), Postoperative Delirium, Postoperative Recovery in Elderly Patients
Conditions
Keywords
bispectraindex, sevoflurane, anesthesia, elderly, cognition
Brief summary
The goal of this randomized clinical trial is to determine whether Bispectral Index (BIS)-guided general anesthesia improves postoperative cognitive recovery and overall quality of recovery in adults undergoing elective hand or arm surgery. The main questions it aims to answer are: Does BIS-guided anesthesia improve postoperative cognitive recovery compared with general anesthesia guided by routine clinical signs? Does BIS-guided anesthesia improve overall postoperative recovery, as measured by the Postoperative Quality of Recovery Scale (PQRS)? Researchers will compare patients receiving BIS-guided general anesthesia with patients receiving clinically guided general anesthesia, in which the BIS monitor records data but the displayed values are concealed from the anesthesia team, to determine whether BIS-guided anesthetic management improves postoperative recovery. An additional comparison group will consist of patients undergoing surgery under intravenous regional anesthesia without general anesthesia. Participants will: undergo elective hand or arm surgery; receive either BIS-guided or clinically guided general anesthesia, or intravenous regional anesthesia without general anesthesia; complete PQRS assessments before surgery and at multiple postoperative time points, including follow-up for up to three months.
Detailed description
The study was designed to investigate the relationship between anesthetic technique, depth of general anesthesia, and postoperative cognitive and overall recovery following elective surgery of the hand or arm.Patients scheduled to receive general anesthesia were randomly allocated using sealed envelopes to one of two general-anesthesia groups. In the BIS-guided group, anesthetic delivery was adjusted using the Bispectral Index, with a target BIS range of 40 to 60. In the clinically guided group, anesthesia was adjusted according to routine clinical indicators, such as blood pressure, heart rate, movement, and other clinical signs. BIS monitoring was also connected in this group, but the values were concealed from the anesthesia personnel and stored for later analysis.General anesthesia was induced with propofol and maintained using sevoiurane and remifentanil according to the study protocol and routine clinical practice. Standard intraoperative monitoring included electrocardiography, noninvasive blood-pressure measurement, oxygen saturation, temperature, and BIS monitoring. Perioperative fluids, treatment of blood-pressure changes, analgesia, and prevention or treatment of postoperative nausea were managed according to the study protocol and usual clinical routines.A separate comparison group consisted of patients whose planned operation was performed using intravenous regional/local anesthesia without general anesthesia. These patients were not randomly assigned to the regional-anesthesia group; their anesthetic method had already been selected as part of their clinical surgical plan.Postoperative recovery was evaluated using the Postoperative Quality of Recovery Scale. Each participant completed a preoperative baseline assessment, and postoperative assessments were planned at approximately 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery. The scale assessed physiological recovery, pain and postoperative nausea or vomiting, emotional recovery, cognitive performance, activities of daily living, and overall patient-reported recovery.Cognitive assessments included orientation, forward digit recall, backward digit recall, word recall, and word generation. Postoperative performance was compared with each participant's own preoperative baseline rather than with a single population-level cutoff.The prospect primary assessment was cognitive recovery at 48 hours after surgery. Additional assessments examined recovery at the other postoperative time points, anesthetic exposure, recorded BIS values, perioperative physiological variables, and early postoperative recovery.
Interventions
General anesthesia was guided by visible Bispectral Index monitoring. Anesthetic delivery was adjusted to maintain a BIS value between 40 and 60. The protocol included propofol for induction and remifentanil with a volatile anesthetic for maintenance.
General anesthesia was guided by routine clinical indicators of anesthetic depth. BIS monitoring was recorded, but its values were concealed from the anesthesia personnel and were not used to adjust anesthetic delivery. The anesthetic regimen otherwise followed the same protocol as the BIS-guided group.
Sponsors
Study design
Masking description
In the clinically guided general-anesthesia group, BIS values were recorded but concealed from the anesthesia personnel. In the BISguided group, the anesthesia personnel could see the BIS values and use them to guide anesthetic delivery. The anesthesia care provider was therefore aware of the assigned management strategy. Participants were under general anesthesia during the intervention. The available protocol documents do not clearly establish whether investigators or postoperative PQRS outcome assessors remained unaware of treatment allocation.
Intervention model description
Three parallel groups were studied. Patients whose planned surgery was to be performed under intravenous regional anesthesia entered a nonrandomized regional-anesthesia comparison group. Patients scheduled for general anesthesia were randomized using sealed envelopes to either BIS-guided anesthesia, targeting a Bispectral Index value of 40 to 60, or clinically guided anesthesia in which BIS values were recorded but concealed from the anesthesia personnel.
Eligibility
Inclusion criteria
* Age 65 years or older. * Scheduled to undergo hand or arm surgery using either intravenous regional anesthesia or general anesthesia. * Able to understand the study information and provide informed consent. * Able to complete the Postoperative Quality of Recovery Scale assessments and cognitive tests.
Exclusion criteria
* Inability to complete the recovery or cognitive assessments. * Deafness or hearing impairment that prevented completion of the assessments. * Bispectral Index monitoring could not be applied or used because of technical or surgical reasons. * Expected duration of surgery of less than 30 minutes or more than 4 hours. * Allergy to nuts or soybeans in participants scheduled to receive general anesthesia. * Pregnancy. * Substance abuse.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Participants With Cognitive Recovery at 48 Hours | 48 hours after surgery | Cognitive recovery was assessed using the cognitive domain of the Postoperative Quality of Recovery Scale (PQRS). The domain included orientation, forward digit recall, backward digit recall, word recall, and word generation. Each participant's postoperative performance was compared with that participant's preoperative baseline using the PQRS recovery criteria. A participant was classiMed as cognitively recovered when all applicable cognitive subtests met the recovery criteria. The outcome was reported as the number and percentage of participants cognitively recovered |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Participants With Cognitive Recovery at Other Postoperative Time Points | 20 minutes, 40 minutes, 24 hours, 14 days, and 90 days after surgery | Cognitive recovery was assessed using the Mve PQRS cognitive subtests: orientation, forward digit recall, backward digit recall, word recall, and word generation. Postoperative performance was compared with each participant's own preoperative baseline using the PQRS recovery criteria. The outcome was reported as the number and percentage of participants cognitively recovered at each time point. |
| Participants With Overall Postoperative Quality of Recovery | 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery | Overall recovery was assessed using the applicable domains of the PQRS (physiological recovery, nociception, emotional recovery, cognition, activities of daily living, and overall patient perspective). Participants were classified as having achieved overall recovery when recovery criteria were met in all applicable PQRS domains, based on comparison with the participant's preoperative baseline where applicable. The outcome was reported as the number and percentage of participants achieving overall recovery. |
| Meeting PQRS Physiological Recovery Criteria | Immediately after emergence and at 20 and 40 minutes after surgery | Physiological recovery was assessed from the PQRS physiological domain, which incorporates systolic blood pressure, heart rate, body temperature, respiratory rate, oxygen saturation, oxygen requirement, airway maintenance, agitation, level of consciousness, and ability to follow a simple command. Recovery was determined according to predefined PQRS physiological recovery criteria. Participants were classified as physiologically recovered when all applicable physiological recovery criteria were met. The outcome was reported as the number and percentage of participants meeting PQRS physiological recovery criteria. |
| Postoperative Pain Severity Assessed With PQRS | Baseline and 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery | Pain was rated using the PQRS nociceptive-domain pain item on a five-category scale: 1, no pain; 2, mild pain; 3, moderate pain; 4, severe pain; and 5, worst imaginable pain. Lower scores indicated less pain. The outcome was reported as pain severity score at each postoperative assessment. |
| Participants Meeting PQRS Emotional Rcovery Criteria | Baseline and 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery | Emotional recovery was assessed using separate PQRS ratings for depression or sadness and anxiety or nervousness. Each item ranged from 1, not at all, to 5, extreme symptoms, with lower scores indicating better emotional status. Recovery was determined according to PQRS emotional recovery criteria by comparison with the participant's preoperative baseline. The outcome was reported as the number and percentage of participants meeting emotional recovery criteria. |
| Postoperative nausea and vomiting | Baseline and 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery | Nausea, retching, and vomiting were assessed using the PQRS nociceptive-domain nausea and vomiting item. Scores ranged from 1, no nausea, retching, or vomiting, to 5, continuous retching or vomiting. Lower scores indicated fewer symptoms. Nausea and vomiting severity scores were assessed and summarized at each postoperative time point. |
| Participants Meeting PQRS Activities of Daily Living Recovery Criteria | Baseline and 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery | Activities of daily living were assessed through the participant's ability to stand, walk, eat and drink, and dress without assistance. Each activity was rated as 1, unable; 2, able with difficulty; or 3, able with ease. Higher scores indicated better function. Recovery was determined according to PQRS activities of daily living recovery criteria by comparison with the participant's preoperative baseline. Participants were classified as recovered when all applicable activities met recovery criteria. The outcome was reported as the number and percentage of participants meeting activities of daily living recovery criteria. |
| Patient-Reported Overall Recovery and Satisfaction Assessed With PQRS | 20 minutes, 40 minutes, 24 hours, 48 hours, 14 days, and 90 days after surgery | The PQRS overall-perspective domain assessed the perceived effect of surgery on the participant's overall perspective of recovery and satisfaction with anesthesia. Items were rated on five-category scales, with lower scores indicating less negative impact or greater satisfaction. Recovery was determined according to PQRS overall-perspective recovery criteria. The outcome was reported as the number and percentage of participants meeting overall-perspective recovery criteria at each postoperative assessment. |
Countries
Sweden
Contacts
Department of Anesthesia and intensivecare University Hospital Örebro