title: Moderate-to-deep sedation technique, using propofol and ketamine, allowing synchronised breathing for magnetic resonance high-intensity focused ultrasound (MR-HIFU) treatment for uterine fibroids: a pilot study.
abstract: BACKGROUND
  Magnetic resonance high-intensity focused ultrasound (MR-HIFU) treatment for uterine fibroids is rapidly gaining popularity as a treatment modality. This procedure is generally uncomfortable, painful, and requires minimal or absence of movement and an MR-HIFU synchronised breathing pattern of the patient. Procedural sedation and analgesia protocols have become the standard practice in interventional radiology departments worldwide. The aim of this study was to explore if a sedation regimen with low-dose propofol and ketamine performed by trained non-medical sedation practitioners could result in relief of discomfort for the patient and in adequate working conditions for MR-HIFU treatment for uterine fibroids.
  
  
  METHODS
  In this study, conducted from August 2013 until November 2014, 20 patients were subjected to MR-HIFU treatment of uterine fibroids. Patients were deeply sedated using intravenous propofol and esketamine according to a standardised hospital protocol to allow synchronisation of the breathing pattern to the MR-HIFU. The quality of sedation for MR-HIFU and complications were recorded and analysed. The side effects of the sedation technique, the propofol and esketamine consumption rate, the duration of recovery, and patient satisfaction after 24 h were examined.
  
  
  RESULTS
  A total of 20 female patients (mean age 42.4 [range 32-53] years) were enrolled. Mean propofol/esketamine dose was 1309 mg/39.5 mg (range 692-1970 mg/ 23.6-87.9 mg). Mean procedure time was 269 min (range 140-295 min). Application of the sedation protocol resulted in a regular breathing pattern, which could be synchronised with the MR-HIFU procedures without delay. The required treatment was completed in all cases. There were no major adverse events. Hypoxemia (oxygen desaturation <92%) and hallucinations were not observed.
  
  
  CONCLUSIONS
  The use of a specific combination of IV propofol and esketamine for procedural sedation and analgesia reduced the discomfort and pain during MR-guided HIFU treatments of uterine fibroids. The resulting regular breathing pattern allowed for easy synchronisation of the MR-HIFU procedure. Based on our results, esketamine and propofol sedation performed by trained non-medical sedation practitioners is feasible and safe, has a low risk of major adverse events, and has a short recovery time, avoiding a session of general anaesthesia.
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, Heidelberglaan 100, Huispostnr.: F 04.5.16, 3584 CX Utrecht, The Netherlands.
authors.forename: Hermanus H B
authors.initials: HHB
authors.lastname: Vaessen
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: F M
authors.initials: FM
authors.lastname: Knuttel
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: J M M
authors.initials: JMM
authors.lastname: van Breugel
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M E
authors.initials: ME
authors.lastname: Ikink
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, Heidelberglaan 100, Huispostnr.: F 04.5.16, 3584 CX Utrecht, The Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: Dieleman
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M A A J
authors.initials: MAAJ
authors.lastname: van den Bosch
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, Heidelberglaan 100, Huispostnr.: F 04.5.16, 3584 CX Utrecht, The Netherlands.
authors.forename: J T A
authors.initials: JTA
authors.lastname: Knape
keywords: Deep propofol and esketamine sedation; Hallucinations and sedation-related complications; MR-HIFU uterine fibroids treatment; Safety