Effect of Different Body Positions on Hypoxemia During Recovery in Patients Undergoing Painless Gastroscopy and Colonoscopy
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: lateral decubitus head-up position (LH group), supine head-up position (SH group), standard lateral decubitus position group (SL group).
- Who it may be relevant to
- Registry conditions: Postoperative Hypoxemia. Basic parameters: from 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- China
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Effects of Lateral Decubitus Head-up Position, Supine Head-up Position, and Standard Lateral Decubitus Position on Hypoxemia During Recovery in Patients Undergoing Painless Gastroscopy and Colonoscopy: A Multicenter, Three-arm Randomized Controlled Trial
Overview
Through a multicenter, three-arm randomized controlled trial design, this study aimed to compare the effects of three positioning strategies-side-lying with elevated head position, supine with elevated head position, and standard side-lying position-on the incidence of hypoxemia during the recovery phase in patients undergoing painless gastroscopy and colonoscopy. The goal was to provide clinicians with a simple, non-invasive, and cost-effective optimization strategy.
Detailed description
Painless gastroscopy and colonoscopy have become the gold standard for screening and diagnosing gastrointestinal diseases due to their high patient comfort and excellent compliance rates, with their clinical application expanding annually. This procedure is performed under intravenous general anesthesia to achieve painlessness; however, anesthetic agents exert inhibitory effects on the patient's respiratory center. Additionally, the procedural manipulation causes irritation to the airways and gastrointestinal tract, leading to a high incidence of hypoxemia during the postoperative recovery phase-the most common respiratory adverse event associated with painless gastroscopy and colonoscopy. Mild cases may prolong patient recovery time, while severe cases can result in serious complications such as hypoxic brain injury or cardiac arrest, directly compromising patient safety and healthcare experience.
Positioning is a critical non-pharmacological intervention factor influencing perioperative respiratory function in patients undergoing painless gastroscopy and colonoscopy. Different positions alter thoracic compliance, airway patency, and diaphragmatic position, thereby affecting the patient's ventilation and oxygenation status. Currently, the standard lateral decubitus position is routinely used for painless gastroscopy and colonoscopy, and it has been demonstrated to reduce the incidence of hypoxemia. However, this position presents challenges such as difficulties in patient monitoring and localized pressure-related discomfort. In contrast, the supine head-up and lateral decubitus head-up positions, by elevating the head and adjusting the body angle, effectively mitigate tongue base prolapse and improve thoracic expansion, theoretically reducing the risk of hypoxemia. Nevertheless, there is currently a lack of multicenter, large-sample, prospective randomized controlled studies to compare the efficacy and safety of these three positions in preventing hypoxemia in recovery rooms for painless gastroscopy and colonoscopy patients. Consequently, there is no unified evidence-based guideline for selecting the optimal clinical positioning.
Based on this, this study focuses on three clinically common positions and employs a multicenter, three-arm, randomized controlled parallel design to systematically investigate the effects of lateral supine with head elevated, supine with head elevated, and standard lateral position on postoperative hypoxemia in patients undergoing painless gastroscopy and colonoscopy. The aim is to fill a research gap in this field and provide high-quality evidence-based medical data to optimize postoperative position management during recovery and reduce adverse respiratory events following painless gastrointestinal endoscopy.
Special Note：Prespecified subgroup analyses will be conducted based on age (\<65 vs ≥65), sex, BMI, ASA class, smoking and alcohol use, Mallampati score, anesthetic agent (clobupol or propofol), type of endoscopy (gastroscopy, colonoscopy, or gastroenteroscopy), Ramsay sedation score (2-4), pre-procedure hypoxemia, prior pulmonary surgery, OSA, respiratory disease, and intra-procedural hypoxemia (SpO₂ ≤90% for \>10 seconds). The influence of heterogeneity on the primary outcome will also be evaluated.
Interventions
- Procedure lateral decubitus head-up position (LH group)
An angle measuring device is placed beside the head of the examination bed to facilitate precise adjustment of the head position. Upon admission to the recovery room, the patient's Ramsay Sedation Scale score is assessed by an independent investigator (the attending anesthesiologist): 1 = agitated; 2 = fully awake, calm and cooperative; 3 = drowsy but responsive to verbal commands; 4 = drowsy but responsive to touch or pain; 5 = asleep but slow to respond to touch or pain; 6 = deep sleep with no - Procedure supine head-up position (SH group)
An angle measuring device is placed beside the head of the examination bed to facilitate precise adjustment of the head position. Upon admission to the recovery room, the patient's Ramsay Sedation Scale score is assessed by an independent investigator (the attending anesthesiologist): 1 = agitated; 2 = fully awake, calm and cooperative; 3 = drowsy but responsive to verbal commands; 4 = drowsy but responsive to tactile or pain stimuli; 5 = asleep but slow to tactile or pain responses; 6 = deep sl - Procedure standard lateral decubitus position group (SL group)
An angle measuring device was placed beside the head of the examination bed to facilitate precise adjustment of the head position. Upon admission to the recovery room, the patient's Ramsay Sedation Scale was assessed by an independent investigator (the attending anesthesiologist): 1 = agitated; 2 = fully awake, calm and cooperative; 3 = drowsy but responsive to verbal commands; 4 = drowsy but responsive to touch or pain; 5 = asleep but slow to respond to touch or pain; 6 = deep sleep with no res
Primary outcome measures
- Incidence of recovery-phase hypoxemia [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
Secondary outcome measures (11)
- Incidence of Subclinical Respiratory Depression during Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes.]
- Overall Incidence of Airway Intervention During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Cough Severity Grade During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Length of Stay in Post-Anesthesia Care Unit (PACU) [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Respiratory Comfort Score During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- PACU Nurse Satisfaction Score [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Incidence of Tachycardia During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Incidence of Bradycardia During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Incidence of Hypotension During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Incidence of Nausea or Vomiting During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
- Incidence of Laryngospasm During Recovery [Time frame: From PACU admission until discharge, assessed up to 30 minutes]
Eligibility criteria
Inclusion criteria
- Age ≥ 18 years.
- Both sexes.
- American Society of Anesthesiologists (ASA) physical status classification I-III.
- Scheduled for combined painless esophagogastroduodenoscopy/colonoscopy or either of the two procedures.
- Ability to understand the study protocol and provide written informed consent.
- A broad set of inclusion criteria was adopted to enroll a patient population that better reflects routine clinical practice. The study aimed to enhance the generalizability of the findings by including patients with various comorbidities, such as preprocedural hypoxemia (room-air SpO₂ ≤ 90%), history of pulmonary surgery, obstructive sleep apnea (OSA), and other pulmonary conditions (including asthma, COPD, chronic bronchitis, emphysema, and pulmonary bullae).
Exclusion criteria
- Severe cardiovascular or cerebrovascular diseases.
- Pregnant patients.
- History of hypersensitivity to ciprofol.
Withdrawal Criteria:
- Endotracheal intubation required during the procedure.
- Voluntary withdrawal requested by the patient or their legal representative.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Single blind
- Primary purpose
- Treatment
Study locations
China · 1 center
- General hospital of Ningxia medical university, Yinchuan, Ningxia — Yinchuan
Identifiers
NCT: NCT07587970 · dywe0002