Semi-sitting Versus Supine Position in Endoscopic Skull Base Surgery (PosESS)

Semi-sitting Versus Supine Position in Endoscopic Skull Base Surgery (PosESS-Study) - Study Protocol for a Randomized-controlled Single-blinded Superiority Trial

This study is to prospectively compare the standard supine (control group) and the semi-sitting position (head elevation of 30°; intervention group) in endoscopic endonasal pituitary surgery.

Study Overview

• Status: Recruiting
• Conditions: Pituitary Adenoma
• Intervention / Treatment: Procedure: Endonasal endoscopic pituitary surgery in semi-sitting position; Procedure: Endonasal endoscopic pituitary surgery in supine position

Detailed Description

The endonasal endoscopic approach (EEA) for pituitary surgery is standardly performed with the patient in supine position (SP). The semi-sitting position (SSP) is routinely used for the traditional microscopic transsphenoidal approach and also for posterior fossa surgery. The SSP results in lower intracranial pressure when compared to the supine position due to decreased venous congestion. As a result, intraoperative bleeding may be reduced, potentially leading to decreased surgical morbidity and improved surgical workflow. Studies during endoscopic sinus surgery have shown a significant reduction of blood loss when the patient is placed in a reverse Trendelenburg position with a head elevation of 30°. This study is to prospectively compare the standard supine (control group) and the semi-sitting position (head elevation of 30°; intervention group) in endoscopic endonasal pituitary surgery.

• Study Type: Interventional
• Enrollment (Estimated): 54
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jonathan Rychen, Dr. med.; Phone Number: +41 61 328 51 84; Email: Jonathan.Rychen@usb.ch
• Study Contact Backup: Name: Michel Röthlisberger, Dr. med.; Phone Number: +41 61 328 54 48; Email: Michel.Roethlisberger@usb.ch

Study Locations

• Switzerland
  • Basel, Switzerland, 4031
    • Recruiting
    • Department of Neurosurgery, University Hospital Basel
    • Contact: Jonathan Rychen, Dr. med.; Phone Number: +41 61 328 51 84; Email: Jonathan.Rychen@usb.ch
    • Contact: Michel Roethlisberger, Dr. med.; Phone Number: +41 61 328 54 48; Email: Michel.Roethlisberger@usb.ch

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients with a presumed pituitary pathologies who are suitable for endoscopic endonasal surgical resection

Exclusion Criteria:

• Patients with known hemorrhagic or thrombophilic disorders
• Patients with conditions associated with high central venous pressure: congestive heart failure, pulmonary hypertension, chronic obstructive pulmonary disease (COPD), interstitial lung disease, pregnancy
• Patients with poor cardiopulmonary condition (unable to perform 4 metabolic equivalents without stopping (climb a flight of stairs))

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Study Intervention; Endonasal endoscopic pituitary surgery in semi-sitting position	Procedure: Endonasal endoscopic pituitary surgery in semi-sitting position; Patients will be placed in semi-sitting position. To achieve the semi-sitting position, the patient is placed in supine position. The operating table is then separated and flexed to elevate the torso (angle of 30°). The head, which is fixed in a head clamp, is slightly flexed to bring the floor of the sella right in front of the surgeon and gently rotated toward the operating team.
Active Comparator: Control Intervention; Endonasal endoscopic pituitary surgery in supine position	Procedure: Endonasal endoscopic pituitary surgery in supine position; Patients will be operated in the standard supine neutral position

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative blood loss	Intraoperative blood loss, calculated as follow: volume in the suction bag minus volume of rinsing water in Milliliters (ml). The surgery is divided into four steps: 1. endonasal phase, 2. osteodural exposure. 3. sellar stage and 4. skull base defect closure. For each step, the primary outcome will be assessed.	Intraoperative
Frequency of interruption of the surgical workflow due to disturbing blood or a bleeding in the surgical field (number)	Frequency of interruption of the surgical workflow due to disturbing blood or a bleeding in the surgical field. This will be assessed by an independent blinded neurosurgeon, who will watch the operative video after the surgery.	During surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in intraoperative Mean Arterial Pressure (MAP)	MAP will be monitored during the whole surgery using the software Copra ©, which allows a continuous data extraction	Intraoperative
Amount of intravenous fluid administered during surgery (ml)	Amount of intravenous fluid administered during surgery (ml)	Intraoperative
Need for vasoactive drugs (vasopressors) (number)	Need for vasoactive drugs (vasopressors) (number)	at Day 1 (day of surgery)
Incidence of air embolism (number)	Incidence of air embolism (number)	at Day 1 (day of surgery)
Operative time (minutes)	Operative time (minutes)	During surgery
Degree of descent or prolapse of the diaphragma sellae into the sellar cavity	Intraoperative assessment of the degree of descent or prolapse of the diaphragma sellae into the sellar cavity (class I to V, according to the classification of Abdelmaksoud et al)	Intraoperative
Occurrence of a cerebrospinal fluid (CSF) leak during surgery (assessed by the operating neurosurgeon) (yes/ no)	Occurrence of a cerebrospinal fluid (CSF) leak during surgery (assessed by the operating neurosurgeon)	During surgery
Surgical ergonomics	Surgical ergonomics assessed by the means of a standardized questionnaire. The surgeon will be asked to rate the intensity of neck and arm discomfort and the frequency of surgical flow interruption due to a suboptimal trajectory of the endoscope and the instruments due to the patient Position (1 = no discomfort, 2 = medium discomfort, 3 = high discomfort).	at Day 1 (day of surgery)
Incidence of rhinoliquorrhoea (number)	Incidence of rhinoliquorrhoea (number)	at 3 months after surgery

Collaborators and Investigators

• Sponsor: University Hospital, Basel, Switzerland
• Investigators: Principal Investigator: Jonathan Rychen, Department of Neurosurgery, University Hospital Basel

Study record dates

Study Major Dates

• Study Start (Actual): January 22, 2021
• Primary Completion (Estimated): June 1, 2024
• Study Completion (Estimated): June 1, 2024

Study Registration Dates

• First Submitted: October 5, 2020
• First Submitted That Met QC Criteria: October 6, 2020
• First Posted (Actual): October 14, 2020

Study Record Updates

• Last Update Posted (Actual): November 2, 2023
• Last Update Submitted That Met QC Criteria: November 1, 2023
• Last Verified: November 1, 2023

More Information

Terms related to this study

• Keywords: endoscopic endonasal pituitary surgery; endoscopic skull base surgery; intracranial venous pressure; venous air embolism
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neoplasms by Histologic Type; Neoplasms; Neoplasms by Site; Neoplasms, Glandular and Epithelial; Endocrine System Diseases; Endocrine Gland Neoplasms; Hypothalamic Diseases; Hypothalamic Neoplasms; Supratentorial Neoplasms; Brain Neoplasms; Central Nervous System Neoplasms; Nervous System Neoplasms; Adenoma; Pituitary Neoplasms; Pituitary Diseases
• Other Study ID Numbers: 2020-02115; ch20Rychen

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No