Litter Packaging in the Lateral Position: Effects of Position and Vacuum Mattress Packaging on Pulmonary Function

This is a study to look at the effect on breathing of various ways to package a person in a rescue litter. We will measure lung function in a litter, lying down, lying down in a vacuum mattress, one the side in a vaccum mattress, and vertical in a vacuum mattress.

Study Overview

• Status: Not yet recruiting
• Conditions: Trauma
• Intervention / Treatment: Other: Patient packaging in a rescue litter

Detailed Description

After acknowledging informed consent, each subject will do baseline sitting pulse oximetry (device) and forced vital capacity (FVC) and 1-second forced expiratory volume (FEV1) three times. After obtaining a baseline, the subject will be secured with a MedTech-VSB 6 foot vacuum mattress (MedTechSweden, Geneseo, IL) in a Ferno-Washington Model 71 litter (Ferno-Washington, Wilmington, OH) using 1-inch tubular webbing, following the methodology of the National Cave Rescue Commission but with no padding and no blankets, see figure 1 .8 The mattress will be deflated (stiffened) to start after securing into the litter with webbing. The litter will be rigged for suspension in the horizontal supine and horizontal lateral positions. We will measure FEV1 and FVC will be repeated in each of 4 positions; supine on a non-stiffened mattress in a horizontal litter (see figure 1), supine on a stiffened mattress in a horizontal litter, in lateral decubitus position in a stiffened mattress in a horizontal litter (see figure 2), and supine, with a stiffened mattress in a vertical litter. The order will be randomly assigned to eliminate any learning effect. The calculated sample size is 10, which should be easily enough to see a difference between baseline and just lying flat. The anticipated change in pulmonary function in the mattress will be in addition to lying down, but not as big as this. So to find this smaller change we anticipate needing 24, this allows for doing all 24 potiential orders of 4 procedures. We will do a preliminary analysis after 12 person, but will continue to 24 if there is no demonstrated difference with the mattress at 12, (see Table 1). In each case, the patient will stay in the position for 1 minute after completing spirometry to measure oxygen saturation again.

1,2,3,4 2,1,3,4 3,1,2,4 4,1,2,3 1,2,4,3 2,1,4,3 3,1,4,2 4,1,3,2 1,3,2,4 2,3,1,4 3,2,1,4 4,2,1,3 1,3,4,2 2,3,4,1 3,2,4,1 4,2,3,1 1,4,2,3 2,4,1,3 3,4,1,2 4,3,1,2 1,4,3,2 2,4,3,1 3,4,2,1 4,3,2,1 Table 1, orders of testing

The litter will be raised 6 inches off of the ground prior to measurement. Anchors to support his will be the patio sun structure at UCSF which has been approved by local building supervisors and used for several other trials, or using trees at other sites. The PI and co-PIs have extensive training and experience evaluating anchors for life support in technical rope exercises. We will not use a crash pad in this set of experiments as the subject will be no more than 6 inches off of the ground and a six inch thick pad will make it harder to quickly intervene even if something did go wrong.

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Roger B Mortimer, MD; Phone Number: 15594996450; Email: roger.mortimer@ucsf.edu
• Study Contact Backup: Name: Michelle Horwege, MSHCA; Phone Number: 5594996450; Email: michelle.horwege@ucsf.edu

Study Locations

• United States
  • California
    • Fresno, California, United States, 93701
      • University of California, San Francisco

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Subjects must be 18 to 65 years old. Per the harness manufacturer's recommendation, participants must weigh between 130 and 300 pounds and have a waist between 32 and 42 inches.

Exclusion Criteria:

• Weight greater than 300 pounds or less than 130 pounds, pregnancy, any known heart condition or murmur or lower extremity edema or wheezing detected on pre-participation exam, or a waist size <32" or >42". Prior to suspension, female participants of childbearing potential will self-administer an FDA approved urine pregnancy test supplied by the investigator. Results will be verified by the investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Comparison of pulmonary function by litter packaging; Order of packaging	Other: Patient packaging in a rescue litter; Different packaging paradigms in a rescue litter done in a random order.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Forced Vital Capacity	Forced Vital Capacity	1 hour
1 second forced vital capacity	1 second forced vital capacity	1 hour

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Investigators: Principal Investigator: Roger B Mortimer, MD, UCSF - Fresno

Study record dates

Study Major Dates

• Study Start (Estimated): August 15, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: June 8, 2026
• First Submitted That Met QC Criteria: June 8, 2026
• First Posted (Actual): June 12, 2026

Study Record Updates

• Last Update Posted (Actual): June 12, 2026
• Last Update Submitted That Met QC Criteria: June 8, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: trauma; pulmonary function; search and rescue
• Additional Relevant MeSH Terms: Wounds and Injuries
• Other Study ID Numbers: 26-46885

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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