Use of Tragus Pressure in Guiding Emergence From Anaesthesia
Condition: Anesthesia
Study type: Interventional

Summary: 
      The aims of this study is to evaluate the effectiveness of tragus pressure application in
      predicting or facilitating recovery from general anaesthesia, and compare the reliability of
      tragus pressure guided recovery/ emergence from anaesthesia to conventional modes of recovery
    

Detailed description: 
      More than 70% of general anaesthesia are now performed with laryngeal mask (LMA) as the
      airway support device with state of the art intra-operative monitoring such as end tidal
      inhalational anaesthetic agent concentration and fronto-temporal electroencephalographic
      waves analysis such as the Bispectral index score (BIS) and entropy. The use of LMAs have
      promised rapid turnover allowing more patients to be operated in the limited operating
      theatres' time. This comes with the additional price of losing the continuity of advanced
      monitoring devices in the post anaesthesia units, the best being end tidal carbon dioxide
      analysis. When patients are brought to the PACU, much of the monitoring of emergence from
      anaesthesia is fairly done through clinical measures such as motor activity, response to
      auditory stimuli, tactile taps on shoulder and occasional nociceptive stimuli such as sternal
      rub. The timing of the responsiveness of these stimuli is unknown and nursing support teams
      are unable to suggest a frame of time on when the patient would recover. One of the main
      reasons for this unpredictability is that the recovery is not planned based on the last
      recorded end tidal anaesthetic agent concentration before leaving the operating theatre to be
      shifted to PACU, but by an approximation of time since the patient has arrived in PACU and by
      early signs of recovery such as appearance of forehead wrinkles or motor activities. The
      incidence of airway events such as laryngospasm, obstruction after removal of airway devices,
      desaturations from resedation/ apnea and rescue measures such as reintubation/ ambu
      ventilation needed globally and from our local data is up to 1-5%. The incidence is higher
      with children and patients with reactive airways, obesity and associated complicating
      comorbidities. Using BIS monitoring and end tidal agent analysis for each of the 18 post
      anaesthesia care unit bays for recovering patients scientifically is not a cost-effective
      initiative. The tragus pressure technique has been known to be appropriate stimuli that has
      adequate stimulation of reticular activating system (RAS) without producing nociception that
      can trigger airway events such a laryngospasm. Physiological sleep studies have quoted that
      tragus pressure can contribute to arousal without causing vagotonic response that is known to
      occur from 'startle response' or sudden emergence. Through this study we propose to evaluate
      the consistency in predictability of recovery from general anaesthesia and deep sedation with
      Ramsay score 3 through application of tragus pressure. The presence of reflex pupillary
      dilatation and early signs of recovery such as swallowing, gentle grimace and minor
      peripheral motor movements, we propose, gives a predictable plane of recovery from
      anaesthesia where the LMAs are removed safely without treading the dreaded stage 2 of
      excitability of anaesthesia. The proposed method also allows for continued responsiveness of
      patient with coherent verbal responses to auditory stimuli after safe removal of the airway,
      thereby minimizing the incidence of airway complication and hence the interventions required
      for the same. The continued alert responsiveness of the patient also allows for the post
      anaesthesia unit team to attend to other patients who might need more immediate care.
    

Intervention name(s): Guiding Emergence From Anaesthesia With Tragus Pressure; Guiding Emergence From Anaesthesia Without Tragus Pressure
Intervention type(s): Procedure; Procedure
Intervention description(s): Use of tragus pressure in guiding patients from emergence from anaesthesia post-surgery; Usual clinical routine practice in guiding patients from emergence from anaesthesia post-surgery
Intervention MeSH terms: Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Anaesthesia Emergence