Study on General Population of the Effect on Airway Protection of Drugs Used During Induction of General Anesthesia

NCT04413422 | Completed

• 1 other identifier: 16/215-O
• Study Type: observational
• Target: 20
• Locations: 0 countries
• Sites: N/A

Brief Summary

Upper esophageal sphincter is a high pressure zone of the pharynx and protects airway from aspiration of esophageal or gastric contents. Existing literature concludes that many of the drugs employed to induce general anesthesia descend that pressure. However, most participants of those studies were under 64 years old and were given sedatives or local anesthetics to ease the esophageal measurements which can interfere with the results obtained. The hypothesis was to confirm the hypnotics effects on upper esophageal sphincter with the aim to find out which of them could be a better choice in order to reduce airway aspiration risk during induction of anesthesia, specially during emergency surgery, when a empty stomach is not guaranteed. Twenty patients who were planned for general surgery were studied: 12 men and 8 women, aged 39 to 84 years old. The effect of three commonly used hypnotics was tested: propofol, etomidate, and thiopental. Written informed consent was explained to all participants who freely signed it after having understood and accepted it. After 6-8 hours fast, patients were monitored with entropy (which gives information about patients´ level of consciousness), electrocardiogram, pulse oximetry (measures blood oxygen), and sphingomanometry (measures blood pressure). Registry of upper esophageal sphincter pressure was obtained through solid state high resolution manometry. A lubricated manometric probe was introduced through the nostril to locate it from the pharynx to the stomach using no sedation. After 1 minute to make the patient feel more comfortable, the induction of anesthesia took place employing one of the three drugs for this purpose mentioned above. Comparison of upper esophageal sphincter pressures before and after the hypnotic administration, should give information about which of the three hypnotics, if any, would not led to an unprotected airway and so at increased risk of aspiration.

Conditions

Aspiration

Keywords

upper esophageal sphincter; propofol; etomidate; thiopental; high resolution manometry

Outcome Measures

Primary Outcomes (1)

• Change from baseline upper esophageal sphincter pressure at loss of conciousness.

  Solid state high resolution manometry (Sierra Scientific Instruments, Given Imaging, Los Angeles, California Medtronic, Ireland) was used. High resolution manometry module Manoscan™ permits adquisition and recording of manometry studies. Manometric probe has a diameter of 4.2 mm and consists of 36 circunferential sensors at 1 cm intervals (Medtronic, Irlanda). Each sensor consists of 12 segments distributed radially, detecting pressures in 2.5 mm length. A pressure image is created using 432 measurement points. Sectorial pressures are averaged inside of each sensor through pressure transduction technology "Tact Array". Data adquired using manometry are represented in real time as "topographic" plots. Contour plots show different colours, each of them correspondent to a concrete pressure. Location is represented in the vertical axis and time in the horizontal axis. Data obtained using Manoscan are recorded and posteriorly analized through Manoview Software V. 3.01 (Medtronic Irlanda).

  Time frame: 1 minute after inserting the manometric probe, a basal measure was noted. An average of 1 minute after the hypnotic was given, once entropy had fallen below 60 or otherwise clinical signs showed unconsciousness, another measure was noted.

Secondary Outcomes (1)

• Spectral Entropy

  Although entropy, as all the variables, was measured through all the study, two time points were relevant: Basal and an average of 1 minuteafter the hypnotic was given. Especially important if the second measurement reached a value of 60 or less.

Other Outcomes (4)

• upper esophageal sphincter length

  1 minute after inserting the manometric probe, a basal measure was noted. An average of 1 minute after the hypnotic was given, once entropy had fallen below 60 or otherwise clinical signs showed unconsciousness, another measure was noted.

• Heart rate

  heart rate was monitored continuously throughout the whole study to assess the trend of its values related to two time points: basal and an average of 1 minute after the hypnotic was given.

• Pulse oximetry

  Pulse oxymetry was monitored continuously throughout the whole study to assess the trend of its values related to two time points: basal and an average of 1 minute after the hypnotic was given.

Study Arms (3)

propofol

Those patients planned for general surgery, who received propofol as an induction agent for general anesthesia.

Drug: type of hypnotic used for induction of general anesthesia

etomidate

Those patients planned for general surgery, who received etomidate as an induction agent for general anesthesia.

Drug: type of hypnotic used for induction of general anesthesia

thiopental

Those patients planned for general surgery, who received thiopental as an induction agent for general anesthesia.

Drug: type of hypnotic used for induction of general anesthesia

Interventions

type of hypnotic used for induction of general anesthesia DRUG

etomidate; propofol; thiopental

Eligibility Criteria

• Age: 35 Years - 85 Years
• Sex: all
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Candidates for the study were those patients who, being planned for general surgery between January of 2017 and july of 2019, met all inclusion criteria and none of exclusion criteria. Employing a table of random numbers, patients were distributed randomly in 3 groups depending on the hypnotics they were receiving for induction of general anesthesia: propofol, etomidate or thiopental.

You may qualify if:

• Candidates ought to comply with all these conditions:
• Had been classified by an anesthesiologist (not participating in the study) , at the preanesthetic consult as I, II or III class from the ASA (American Society of Anesthesiologists) classification in reference to his/her anesthetic risk.
• Patients of any gender.
• Patients aged 35 to 85 years old.
• Candidates to planned general surgery to be given general anesthesia.
• Be correctly informed through orally and in writing about the study.
• Voluntary acceptance to participate in the study, voluntary signing the informed consent , which could be revoked at any time through the study.

You may not qualify if:

• Presenting known allergy or hypersensitivity to any of the drugs to be potentially administered.
• Pregnancy.
• Psychiatric history or being on treatment with psychotropic drugs.
• Being on treatment with any of these drugs (which can cause alterations in esophageal motility): prokinetics, sedatives, calcium channel antagonists, nitrates, anticholinergics, tricyclic antidepressants, teophyline.
• Having had esophageal surgery.
• Those who, from an anesthetic or medical point of view could present complications during the process. For example: difficult airway or problems with ventilation.
• Renal or hepatic alteration which may interfere with hypnotics pharmacokinetics.
• Renounce to sign informed consent, therefore not authorizing to participate in the study.
• Esophageal pathology, including gastroesophageal reflux or dysphagia. Given the high frequency of presenting any of these two lasts, tests were given to the candidates to discard their presence. Two questionnaires were employed: "GERD-Q" (GastroEsophageal Disease- Questionnaire) and "EAT-10" (Eating Assesment Tool) for dysphagia.

Sponsors & Collaborators

• Hospital San Carlos, Madrid: lead

Related Publications (10)

• Sivarao DV, Goyal RK. Functional anatomy and physiology of the upper esophageal sphincter. Am J Med. 2000 Mar 6;108 Suppl 4a:27S-37S. doi: 10.1016/s0002-9343(99)00337-x.

  PMID: 10718448 BACKGROUND

• Meyer JP, Jones CA, Walczak CC, McCulloch TM. Three-dimensional manometry of the upper esophageal sphincter in swallowing and nonswallowing tasks. Laryngoscope. 2016 Nov;126(11):2539-2545. doi: 10.1002/lary.25957. Epub 2016 Mar 18.

  PMID: 26990011 BACKGROUND

• Mei L, Dua A, Kern M, Gao S, Edeani F, Dua K, Wilson A, Lynch S, Sanvanson P, Shaker R. Older Age Reduces Upper Esophageal Sphincter and Esophageal Body Responses to Simulated Slow and Ultraslow Reflux Events and Post-Reflux Residue. Gastroenterology. 2018 Sep;155(3):760-770.e1. doi: 10.1053/j.gastro.2018.05.036. Epub 2018 May 24.

  PMID: 29803837 BACKGROUND

• Sundman E, Witt H, Sandin R, Kuylenstierna R, Boden K, Ekberg O, Eriksson LI. Pharyngeal function and airway protection during subhypnotic concentrations of propofol, isoflurane, and sevoflurane: volunteers examined by pharyngeal videoradiography and simultaneous manometry. Anesthesiology. 2001 Nov;95(5):1125-32. doi: 10.1097/00000542-200111000-00016.

  PMID: 11684981 BACKGROUND

• Vanner RG, Pryle BJ, O'Dwyer JP, Reynolds F. Upper oesophageal sphincter pressure and the intravenous induction of anaesthesia. Anaesthesia. 1992 May;47(5):371-5. doi: 10.1111/j.1365-2044.1992.tb02215.x.

  PMID: 1599058 BACKGROUND

• Vanner RG, Pryle BJ, O'Dwyer JP, Reynolds F. Upper oesophageal sphincter pressure during inhalational anaesthesia. Anaesthesia. 1992 Nov;47(11):950-4. doi: 10.1111/j.1365-2044.1992.tb03196.x.

  PMID: 1466434 BACKGROUND

• de Leon A, Ahlstrand R, Thorn SE, Wattwil M. Effects of propofol on oesophageal sphincters: a study on young and elderly volunteers using high-resolution solid-state manometry. Eur J Anaesthesiol. 2011 Apr;28(4):273-8. doi: 10.1097/EJA.0b013e3283413211.

  PMID: 21119519 BACKGROUND

• Thorn K, Thorn SE, Wattwil M. The effects on the lower esophageal sphincter of sevoflurane induction and increased intra-abdominal pressure during laparoscopy. Acta Anaesthesiol Scand. 2006 Sep;50(8):978-81. doi: 10.1111/j.1399-6576.2006.01069.x.

  PMID: 16923093 BACKGROUND

• Thorn K, Thorn SE, Wattwil M. The effects of cricoid pressure, remifentanil, and propofol on esophageal motility and the lower esophageal sphincter. Anesth Analg. 2005 Apr;100(4):1200-1203. doi: 10.1213/01.ANE.0000147508.31879.38.

  PMID: 15781546 BACKGROUND

• Vakkuri A, Yli-Hankala A, Talja P, Mustola S, Tolvanen-Laakso H, Sampson T, Viertio-Oja H. Time-frequency balanced spectral entropy as a measure of anesthetic drug effect in central nervous system during sevoflurane, propofol, and thiopental anesthesia. Acta Anaesthesiol Scand. 2004 Feb;48(2):145-53. doi: 10.1111/j.0001-5172.2004.00323.x.

  PMID: 14995935 BACKGROUND

Study Officials

• Elena Sanz-Sanjosé, MD

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: May 18, 2020
• First Posted: June 4, 2020
• Study Start: January 10, 2017
• Primary Completion: July 18, 2019
• Study Completion: July 18, 2019
• Last Updated: June 4, 2020

Record last verified: 2020-06

Data Sharing

• IPD Sharing: Will not share