Transcutaneous Electrical Stimulation for Apnea Detected by Capnography (TESCapno)

University of Toronto

Status: Enrolling

Conditions: Opioids; Respiratory Depression

Treatments: Device: transcutaneous electrical nerve stimulation (TENS)

Study type: Interventional

Funder types: Other

Identifiers

NCT06823661

55095

Details and patient eligibility

About

After surgery, patients often recover in a special area called the Post Anesthesia Care Unit (PACU). Patients may receive pain medications either during the surgery or afterward in the PACU. While these medications are important for controlling pain, some of them can slow down breathing.

To ensure patients' breathing remains safe, the nurses in the PACU monitor respiratory rate (how many breaths a patient takes per minute) and oxygen levels using standard monitoring equipment. This is the usual way they check for breathing concerns. If these monitors show that a patient's breathing has slowed down too much, nurses may wake the patient up or stimulate them using their voice or gentle physical touch to encourage deeper breaths.

What is this study about? This research is testing a new approach that uses an additional monitor called capnography. Capnography helps detect slowing or stopping of breathing by measuring the carbon dioxide (CO2) exhaled by patients. If the monitor shows slowed or stopped breathing (called apnea, lasting at least 10 seconds), this study will test using a technology called transcutaneous electrical stimulation (TES) to encourage normal breathing.

How does TES work? TES provides a slight, annoying sensation on the patient's skin-enough to wake them up without causing pain. This has been used in other studies to safely restore breathing after surgery. In this study, the researchers are testing whether a new automated device can deliver TES when the capnography monitor detects breathing issues. The goal is to test the feasibility (can this system work in the PACU?) and acceptability (how do patients feel about this approach?) of this technology.

Who can join this study? Adults aged 18 or older who received general anesthesia and medications (opioids) for pain control during or after surgery are eligible. Patients recovering from surgery in the PACU at Toronto General Hospital may be invited to participate.

Why is this study important? The study aims to reduce the risk of opioid-related breathing problems after surgery, making recovery safer and more comfortable for patients.

Enrollment: 60 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Males and females at least 18 years old
• Adults undergoing an elective (General, Plastics, Urology, Gynecologic Oncology, Vascular, Otolaryngology, Transplant) surgery with general anesthesia who are recovering in the PACU
• American Society of Anesthesiologists (ASA) grade I-IV
• Scheduled to be seen at the Pre-Admission Clinic or Surgery Inpatient Unit
• Able to complete questionnaires with or without assistance
• Able to understand the study protocol, its requirements, risks, and discomforts
• Able to provide written informed consent

Exclusion criteria

• A) Preoperative exclusion criteria:

  • American Society of Anesthesiologists (ASA) grade V-VI
  • Urgent or emergent surgical procedures that there is insufficient time prior to anticipated commencement of the procedure for participation in the study
  • Patients with implantable medical electronic devices (eg, pacemaker, implantable cardioverter defibrillator, catheter, and so on.)
  • Patients with febrile illnesses or acute infectious diseases
  • Pregnancy
  • Epilepsy.

• B) Postoperative exclusion criteria:

  • Surgery that would preclude the use of a nasal cannula or face mask used for capnography monitoring (e.g., facial reconstruction)
  • Postoperative mental status precludes application of study equipment, including a nasal cannula/face mask and/or the stimulation pads (e.g., delirium or agitation during recovering from anesthesia, repeated removal of cannula)
  • Postoperative admission to the ICU or any site other than the PACU
  • Need for postoperative assisted ventilation via an endotracheal tube or tracheostomy
  • An abnormal respiratory tract identified during or immediately after surgery can lead to severe respiratory obstruction
  • Patients with cardiac arrhythmia (history of atrial fibrillation or bundle branch block)
  • Skin conditions such as open sores preventing proper application of electrodes
  • Presence of metal implants in both arms
  • Lack of access to upper extremities following surgery for application of the stimulation pads

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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60 participants in 2 patient groups

Transcutaneous Electrical Stimulation (TES)

Experimental group

Description:

All patients assigned to the intervention group will be continuously monitored by capnography, which is attached to the TES device. This monitoring will continuously track end-tidal carbon dioxide (ETCO2) levels. A mild electrical stimulation will be initiated when the episode of apnea ≥10 seconds is detected by the capnography. Patients in the intervention group will receive TES applied to the ventral surface of the forearm via electrodes in response to the apnea lasting for more than or equal to 10 seconds. When apnea persists for more than or equal 10 seconds, a pre-determined, patient-specific mA current stimulus will be administered for one second. If the patient has not taken a breath after the first stimulation, a second stimulus of similar intensity will be administered for three seconds. Subsequently, all stimuli will be administered for three seconds until the apnea criteria have ceased.

Treatment:

Device: transcutaneous electrical nerve stimulation (TENS)

Placebo (Monitor-Only mode)

No Intervention group

Description:

The control group will be monitored by capnography attached to the TES device. The TES electrode will be placed on the ventral surface of the wrist, but no stimulus will be applied (Monitor-Only mode). Participants in the control group will be checked during the PACU stay to make sure that they are still comfortable, and any adverse events will be documented.