An interventional study of Left Paratracheal Pressure and Cricoid Pressure in Cerebral Oxygenation, sponsored by Clinique Saint-Luc. Not yet recruiting at 1 site in Belgium. Open to participants aged 18 Years to 99 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-21.
Sponsored by Clinique Saint-Luc · Not applicable, Interventional, and Basic science
Left paratracheal pressure (LPP) has been proposed as an alternative to cricoid pressure to reduce the risk of regurgitation during induction of general anesthesia. Previous studies suggest that LPP can effectively compress the esophagus without significantly reducing left carotid blood flow. However, its effect on cerebral oxygenation has not yet been evaluated.
The aim of this prospective randomized crossover study is to assess whether application of LPP affects regional cerebral oxygen saturation measured by near-infrared spectroscopy (NIRS) during general anesthesia.
Seventy adult patients undergoing elective surgery under general anesthesia with tracheal intubation will be included. After induction of anesthesia and stabilization, cerebral oxygen saturation will be continuously measured under three conditions: no cervical pressure, left paratracheal pressure at 30 N, and cricoid pressure at 30 N. The order of the two pressure maneuvers will be randomized.
The primary objective is to determine the change in left regional cerebral oxygen saturation during LPP compared with baseline without cervical pressure.
Pulmonary aspiration of gastric contents remains a potentially serious complication of general anesthesia. Cricoid pressure has traditionally been used during induction of anesthesia to reduce the risk of regurgitation, although its effectiveness and its potential effects on airway management remain debated.
Left paratracheal pressure (LPP) has been proposed as an alternative technique based on the frequent left-sided position of the cervical esophagus. Anatomical and clinical studies have suggested that LPP may provide effective esophageal compression while preserving airway management conditions. Previous work from the investigators also showed that application of LPP at 30 N did not significantly decrease left carotid blood flow. However, carotid blood flow is an indirect marker of cerebral perfusion, and the effect of LPP on cerebral oxygenation remains unknown.
PARANIRS is a prospective, single-center, randomized, controlled crossover study designed to evaluate the effect of LPP on regional cerebral oxygen saturation during general anesthesia. Each participant will serve as their own control.
After induction of general anesthesia, neuromuscular blockade, tracheal intubation, and hemodynamic stabilization, bilateral regional cerebral oxygen saturation will be continuously monitored using near-infrared spectroscopy. Measurements will be obtained during a baseline period without cervical pressure and during application of two cervical pressure maneuvers: left paratracheal pressure at 30 N and cricoid pressure at 30 N.
The order of the two cervical pressure maneuvers will be randomized. Each maneuver will be applied for 60 seconds using a calibrated force-measuring device to ensure a constant force of 30 N, with a 60-second washout period between interventions.
Hemodynamic and respiratory variables, including mean arterial pressure, heart rate, peripheral oxygen saturation, and end-tidal carbon dioxide, will also be continuously recorded. The study is intended to determine whether LPP produces a clinically relevant change in regional cerebral oxygenation and to compare its physiological effects with those of conventional cricoid pressure.
Exclusion Criteria:
Participants undergo baseline measurements without cervical pressure, followed by left paratracheal pressure (LPP) at 30 N for 45 seconds, a 60-second washout period, and then cricoid pressure (CP) at 30 N for 45 seconds.
Procedure: Left Paratracheal Pressure · Procedure: Cricoid Pressure
Participants undergo baseline measurements without cervical pressure, followed by cricoid pressure (CP) at 30 N for 45 seconds, a 60-second washout period, and then left paratracheal pressure (LPP) at 30 N for 45 seconds.
Procedure: Left Paratracheal Pressure · Procedure: Cricoid Pressure
A standardized cricoid pressure of 30 N will be applied for 45 seconds using a calibrated force-measuring device. Regional cerebral oxygen saturation, hemodynamic variables, and respiratory variables will be continuously recorded during the intervention.
A standardized cricoid pressure of 30 N will be applied for 45 seconds using a calibrated force-measuring device. Regional cerebral oxygen saturation, hemodynamic variables, and respiratory variables will be continuously recorded during the intervention.
Maximum Change in Left Regional Cerebral Oxygen Saturation During Left Paratracheal Pressure
Maximum absolute change in left regional cerebral oxygen saturation (rSO2), expressed in percentage points, during application of left paratracheal pressure at 30 N compared with the baseline value obtained without cervical pressure.
Time frame: During the 45-second application of left paratracheal pressure, compared with the preceding baseline period
Maximum Change in Right Regional Cerebral Oxygen Saturation
Maximum absolute change in right regional cerebral oxygen saturation (rSO2), expressed in percentage points, during application of each cervical pressure maneuver compared with the baseline value obtained without cervical pressure.
Time frame: During each 45-second cervical pressure intervention, compared with the preceding baseline period
Difference in Change in Left Regional Cerebral Oxygen Saturation Between LPP and Cricoid Pressure
Within-participant difference in the maximum absolute change in left regional cerebral oxygen saturation (rSO2), expressed in percentage points, between left paratracheal pressure at 30 N and cricoid pressure at 30 N.
Time frame: During the two 45-second cervical pressure interventions
Difference in Regional Cerebral Oxygen Saturation Between the Left and Right Hemispheres
Difference in regional cerebral oxygen saturation (rSO2), expressed in percentage points, between the left and right cerebral hemispheres during baseline, left paratracheal pressure, and cricoid pressure.
Time frame: During baseline and each 45-second cervical pressure intervention
Change in Mean Arterial Pressure
Change in mean arterial pressure (MAP), measured in mmHg, during left paratracheal pressure and cricoid pressure compared with baseline.
Time frame: During baseline and each 60-second cervical pressure intervention
Change in Heart Rate
Change in heart rate, measured in beats per minute, during left paratracheal pressure and cricoid pressure compared with baseline.
Time frame: During baseline and each 45-second cervical pressure intervention
Change in Peripheral Oxygen Saturation
Change in peripheral oxygen saturation (SpO2), expressed as a percentage, during left paratracheal pressure and cricoid pressure compared with baseline.
Time frame: During baseline and each 45-second cervical pressure intervention
Change in End-Tidal Carbon Dioxide
Change in end-tidal carbon dioxide (EtCO2), measured in mmHg, during left paratracheal pressure and cricoid pressure compared with baseline.
Time frame: During baseline and each 45-second cervical pressure intervention
Participants Requiring Vasopressor Administration
Number and proportion of participants requiring vasopressor administration during the experimental study period.
Time frame: From baseline measurement through completion of the second cervical pressure intervention, approximately 3 minutes
Participants With Adverse Events Related to Cervical Pressure Maneuvers
Number and proportion of participants experiencing an adverse event considered related to left paratracheal pressure or cricoid pressure during the experimental study period. Events leading to premature interruption of either maneuver will also be recorded.
Time frame: From application of the first cervical pressure maneuver through completion of the second maneuver, approximately 3 minutes
Plan to share: Undecided — The individual participant data sharing plan has not yet been finalized. Any future sharing of de-identified participant-level data will be subject to applicable ethical, regulatory, and institutional requirements.
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Clinique Saint-Luc