Subanesthetic Esketamine for Hemodynamic Stability and Recovery in Elderly Thoracic Surgery Patients

Hebei Medical University Fourth Hospital230 enrolled

Overview

This retrospective study evaluated the effects of a subanesthetic dose of esketamine (0.25 mg/kg) on intraoperative hemodynamic stability and postoperative recovery quality in elderly patients (aged 65-75) undergoing thoracic surgery under general anesthesia. A total of 230 patients were included and randomly assigned to receive either esketamine or placebo during anesthesia induction. Key outcomes included blood pressure and heart rate stability, catecholamine levels, recovery time, incidence of adverse events such as delirium or nausea, and opioid use.

Elderly patients are at increased risk for anesthesia-related complications due to reduced physiological reserves and comorbidities. Thoracic surgery further increases this risk by inducing significant cardiovascular and sympathetic stress. Esketamine, the S-enantiomer of ketamine, possesses sympathomimetic and analgesic properties that may help stabilize circulation and reduce postoperative complications when used at subanesthetic doses. In this single-center, randomized controlled trial, patients aged 65-75 scheduled for elective thoracic surgery were administered either 0.25 mg/kg esketamine or normal saline during anesthesia induction. Hemodynamic parameters (mean arterial pressure, heart rate), plasma catecholamine concentrations (norepinephrine, epinephrine), and adverse cardiovascular responses were recorded. Postoperative outcomes included emergence time, PACU stay, incidence of delirium, hallucinations, nausea and vomiting, and opioid consumption.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Enrollment

230

Conditions

Interventions

EsketamineDRUG

Intravenous administration of a subanesthetic dose of esketamine (0.25 mg/kg) during induction of general anesthesia. The drug was administered slowly over approximately 30 seconds after midazolam (2 mg) and sufentanil (50 µg), and prior to propofol (2 mg/kg) and rocuronium (0.6 mg/kg). The goal was to evaluate its effect on intraoperative hemodynamic stability and postoperative recovery in elderly patients undergoing thoracic surgery.

Normal Saline (0.9% Sodium Chloride)DRUG

Intravenous administration of an equivalent volume of 0.9% normal saline during anesthesia induction, matching the timing and method of the esketamine group. Used as a placebo comparator.

MidazolamDRUG

Intravenous administration of 2 mg midazolam during anesthesia induction for sedation. Administered prior to study drug.

SufentanilDRUG

Intravenous administration of 50 µg sufentanil for analgesia during anesthesia induction. Administered prior to study drug.

propofolDRUG

Intravenous administration of 2 mg/kg propofol for loss of consciousness during anesthesia induction. Administered after study drug.

RocuroniumDRUG

Intravenous administration of 0.6 mg/kg rocuronium to facilitate neuromuscular blockade and endotracheal intubation.

Eligibility

Sex: ALLMin age: 65 YearsMax age: 75 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age 65-75 years * Scheduled for elective thoracic surgery (e.g., lobectomy, bullectomy) * ASA physical status I-III * Adequate cardiopulmonary function * Able to provide informed consent * Preoperative systolic blood pressure \<160 mmHg with stable control * No cognitive impairment Exclusion Criteria: * Severe cardiovascular disease (e.g., unstable angina, heart failure ≥ NYHA class III) * History of cerebrovascular disease * Uncontrolled hypertension (SBP \>180 mmHg) * Severe hepatic or renal dysfunction * Chronic psychiatric illness or long-term CNS-active drug use * Allergy to ketamine or its derivatives * Elevated intracranial or intraocular pressure * Use of monoamine oxidase inhibitors within 24 hours before surgery * History of substance abuse

Outcomes

Primary Outcomes

Maximum Decrease in Mean Arterial Pressure (MAP) During Anesthesia Induction

The lowest value of MAP recorded between the time of anesthesia induction and skin incision, compared to baseline MAP before induction. This outcome evaluates the degree of hemodynamic depression associated with induction agents and the protective effect of esketamine.

Time frame: From anesthesia induction to skin incision (approximately 15 minutes)

Secondary Outcomes

Time to Eye Opening After Surgery

The duration between the end of surgery and the patient's spontaneous eye opening, measured in minutes in the PACU.

Time frame: Postoperative period in PACU (within 30 minutes after surgery)

Incidence of Hypotension During Anesthesia Induction

Defined as mean arterial pressure (MAP) \< 65 mmHg or the need for vasopressor intervention (norepinephrine) between induction and intubation.

Time frame: From anesthesia induction to intubation (approximately 5 minutes)

Incidence of Postoperative Delirium

Evaluated using the Confusion Assessment Method for the ICU (CAM-ICU) during the recovery period.

Time frame: From PACU admission to hospital discharge (up to 24 hours postoperatively)

Postoperative Morphine Requirement

Number of patients requiring morphine for pain relief and total dose (mg) administered in the PACU.

Time frame: Within 1 hour after surgery in PACU