Pain With Differing Insufflation Pressures During Laparoscopic Hysterectomy
Phase: NA
Conditions: Post Operative Pain
Sponsor: University of Tennessee

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
NCT Number: Not Yet Assigned 
Document Date: 7/12/2024 
 

Study Protocol  
 
The process of insufflation will be used on all laparoscopic gynecological surgical patients and 
for the research protocol the amount of carbon dioxide measuring 12 mmHg used for the 
experimental group B is less than the standard amount of 15 mmHg used for the control group A.  
Insufflation pressures of either 12 mmHg (group B) or 15 mmHg (group A) will be used for this 
research, regardless of the subject’s BMI, however it is noted that for patients with extreme 
upper BMIs, visualization can be more challenging. BMI will be one of the data points recorded 
for patients, however the randomization of the subjects to 12 mmHg (group B) or 15 mmHg 
(group A) will not be dependent on their BMI. Our maximum BMI for inclusion of subjects will 
be a BMI of 55.0.  
Procedures other than Treatments: 
Visit 1 (Day 0) 
• Give informed consent at routine doctor visit (this will take an additional 30-45 min) – 
for research purposes only 
• Information such as your age, weight, height, and medical history such as [previous heart 
attacks, etc.] will be copied from you medical record. Specifically, the following items 
will be collected: age, race, ethnicity, insurance status (public vs. private), body mass 
index (BMI), additional medical health conditions, surgical history-prior abdominal 
surgery, history of chronic pain, history of prior chronic opioid use, pre-operative 
medications – opioid/analgesic, history of alcohol and tobacco use, history of 
depression/anxiety; (this will take an additional 30-45 min) – for standard of care and for 
research purposes;  
 
Visit 2 (Day 1) 
• Post-anesthesia randomization to group A or group B, (this will take an additional 5-10 
min) – for research purposes only; 
• Intra-operative insufflation using 15 mmHg (standard-group A) or 12 mmHg 
(experimental-group B), adjustment of intra-operative insufflation pressure; (this will 
take an additional 5 min-10 min) – insufflation for group A is done as standard of care; 
insufflation for group B is done for research purposes only;  
• Post-operative assessment to include the procedure details: indication for procedure, 
length, estimated blood loss, surgical complications, estimated blood loss, pathology, 
visual analog scale (VAS), pain medication – prescribed and taken, length of hospital 
stay, (this will take an additional 30-45 min) – for standard care and for research 
purposes; 
 
Visit 3 (Day 14 to Day 30) 
• In person post-operative follow-up assessment; (this will take an additional 15-30 min)- 
for standard of care and for research purposes; 
• Collection of postoperative pathology reports, post-operative opioid use; (this will take an 
additional 30-45 min) – for standard of care and for research purposes; 
 
Adverse events will be monitored and collected through the Day 30 visit, to include the 
following categories: Death, Life-threatening, Hospitalization (initial prolonged), Disability or 
Permanent Damage, Required Intervention to Prevent Permanent Impairment or Damage 

(Devices), Other Serious (Important Medical Events). This will be accomplished through 
assessment of all body systems, with specific focus on: respiratory: decreased respirations, 
shallow breathing, decreased SPO2; integumentary: swelling, pressure, or crackling sound skin 
on palpitation of skin, increased abdominal distension; neurological: uncontrolled pain.  
 
For patients randomized to 12 mmHg, if the surgeon deems that the visualization is not adequate 
to safely operate, then they may elect to increase the pressure to the standard 15 mmHg to 
improve visualization.  
 
Statistical Analysis Plan 
 
We have estimated a necessary sample size of 50 participants per group (100 total) with an 
anticipated effect size of 0.54 based on estimated means of 17mm for the experimental arm (SD 
20mm) and 29mm for the control arm (SD 24mm), accounting for expected loss to follow up of 
10%. Patients were randomized using 10 block groups of size 10 each.  
 
We will provide a table of demographic and clinical characteristics by assigned group. For 
continuous variables, we will provide means and standard deviations per group, applying a t-test 
for comparison of independent means. For categorical variables, we will provide counts and 
percentages, applying chi-square test for comparison of proportions.