Evaluation of Providing Coffee to Patients Postoperatively to Decrease Length of Stay in the PACU
Phase: NA
Conditions: PACU Length of Stay, Postoperative Nausea, Postoperative Vomiting, Patient Satisfaction
Sponsor: TriHealth Inc.

RESEARCH PROTOCOL 
 
Date 
4/6/2022 
Title 
Evaluation of providing coffee to patients postoperatively to 
decrease length of stay in the PACU 
Principal Investigator 
Brandon Ballhaus, BSN, RN, CNOR 
Sub-Investigators 
Andrea Dowdy, BSN, RN; Cynthia Kennedy, BSN, RN-BC; Holly 
Mcquillan-Emerson RN, RNC-MNN; Diane Reinert, BSN, RN, CGRN; 
Patrick Bobst, MSN, RN, CPAN 
Research Specialist 
Rachel Baker, PhD, RN, CPN 
Department 
Bethesda North Minimally Invasive Surgery Center; Bethesda 
Surgery Center 
Hatton # 
18-050 
 
 
Purpose of Study    
The purpose of the study is to determine if providing coffee to patients who self-identify as 
coffee drinkers postoperatively will decrease the length of stay in the post-anesthesia care unit 
(PACU).  Decreasing the length of stay in PACU for surgical patient is a pertinent outcome. The 
shorter length of stay can achieve higher patient engagement scores, while simultaneously 
increasing the productivity of the unit. This is achieved by making more beds available for new 
patients coming from the operating room (OR). One thought was that coffee would benefit our 
patients experience through a number of pathways. Initially, the stimulant effect of coffee 
would create a more alert patient. A more alert patient is more likely to comprehend home 
care instruction and be ready for discharge earlier. Coffee is often used as a remedy for 
morning sickness. Ideally the act of drinking coffee or even smelling the coffee may decrease 
the occurrence of Post-Operative Nausea and Vomiting (PONV) in our patient population. 
Finally, patients frequently state that the inability to drink their morning coffee is often more 
difficult than not being able to eat prior to surgery. By allowing those to drink coffee in PACU 
this would make the patient feel that they are being cared for on an emotional level, in addition 
to a physical level. 
 
Hypothesis or Research Question 
Primary Hypothesis: 
Hypothesis 1: Patients who self-identify as coffee drinkers who receive coffee postoperatively 
will experience a shorter length of stay in the PACU compared to patients who self-identify as 
coffee drinkers and do not receive coffee postoperatively. 
 
Secondary Hypotheses: 
Hypothesis 2: Patients who self-identify as coffee drinkers who receive coffee postoperatively 
will experience a lower occurrence of postoperative nausea and vomiting in the PACU 
compared to patients who self-identify as coffee drinkers and do not receive coffee 
postoperatively. 

Hypothesis 3: Patients who self-identify as coffee drinkers who receive coffee postoperatively 
will report higher patient satisfaction compared to patients who self-identify as coffee drinkers 
and do not receive coffee postoperatively. 
 
Background  
After performing a thorough review of the literature, no studies were found that examined 
whether there are benefits of drinking coffee for post-operative patients. There have been a 
few studies that have demonstrated a benefit of three times daily coffee consumption 
following abdominal surgeries. In a study of 80 patients undergoing elective open or 
laproscopic colectomy, Muller and colleagues (2012) found that patients who consumed 100mL 
of coffee three times daily, compared to patients assigned to consume 100mL of water three 
times daily, had a significantly shorter time to first bowel movement. Similarly, Gungorduk and 
colleagues (2017) studied 114 patients who were undergoing total abdominal hysterectomy 
and systematic paraaortic lymphadenectomy and found that compared to a group assigned to 
drink water, those patients assigned to consume coffee 3 times daily postoperatively, had a 
shorter time to bowel motility and ability to tolerate food. While these studies demonstrate 
that coffee consumption was tolerated after surgery, they do not provide evidence about the 
effectiveness of coffee consumption on length of stay and/or postoperative nausea and 
vomiting in the PACU.  
 
Theoretically, coffee consumption is associated with increased brain function. “Coffee is also 
well-known for its positive effects on mental alertness and psychological lift, benefits often 
attributed to caffeine content. Indeed, frequent low doses of caffeine counter the effects of 
extended wakefulness” (Taylor & Demming-Adams, 2007). Additionally, Warner and colleagues 
(2018) state that murine models have demonstrated an enhanced speed of recovery from 
general anesthesia, however this phenomenon has not been examined in humans. Therefore, 
Warner’s team (2018) conducted one of the first (if only) studies examining the association 
between caffeine administration and changes in sedation scores among 151 heavily sedated 
patients in a PACU. Following administration of IV caffeine, RASS scores increased and no 
adverse respiratory events were noted following caffeine administration. The data suggested 
that IV caffeine may enhance speed of recovery from general anesthesia. Warner and 
colleagues’ study provides preliminary evidence that coffee consumption may increase speed of 
recovery. Once again, no studies have examined whether providing coffee to patients 
postoperatively would decrease the length of stay in the PACU compared to not providing 
coffee.  
 
Research Plan  
• Study Design  
A randomized, non-blinded, controlled study will be conducted, with two arms.  
Subjects will be randomized into one of the two following arms:  
• Arm 1: Subjects will receive coffee while in the PACU 
• Arm 2: Subjects will NOT receive coffee in PACU 
 
• Setting for the study 

The study will take place in the Bethesda North Minimally Invasive Surgery Center. This 
unit consists of 3 operating rooms and 7 postoperative recovery bays. The team 
members on this unit provide care for patients undergoing minimally invasive 
outpatient procedures including (but not limited to) Herniorrhaphy Repairs, 
Laparoscopic Cholecystectomies, Lipoma Removals, Hysteroscopies, Uterine Ablations, 
Bladder Slings, Female Sterilization, Breast Reductions and Augmentations, and other 
Plastic Surgery.  There are approximately 10-20 surgeries performed in this setting each 
day. We are a 3 OR Suite facility with 6 Pre-Op Bays and 7 Recovery Bays. 
 
In April 2022, the Bethesda Surgery Center was added as a second recruitment site. This 
unit consists of 4 operating rooms and 8 postoperative recovery bays. The team 
members on this unit provide care for patients undergoing minimally invasive 
outpatient procedures including (but not limited to) Herniorrhaphy Repairs, 
Laparoscopic Cholecystectomies, Hemorrhoidectomies, Lipoma Removals, Eye Muscle 
Repair, Breast Reductions and Augmentations, Abdominoplasty, and other Plastic 
Surgery.  There are approximately 10-20 surgeries performed in this setting each day. 
We are a 4 OR Suite facility with 6 Pre-Op Bays and 8 Recovery Bays. 
 
 
• Participants 
This study will enroll 300 subjects who meet the inclusion/exclusion criteria. 
 
Inclusion criteria: 
1. 18 years old or older 
2. Admitted to Bethesda North Minimally Invasive Surgery Center or the Bethesda 
Surgery Center 
3. Reports to consume at least one cup of coffee a day for at least 5 days in a week 
 
Exclusion Criteria 
1. History of PONV 
2. Pre-existing cardiac arrhythmias 
3. History of seizure disorder 
4. Pregnant 
 
Withdraw Criteria (patients who meet inclusion/exclusion criteria and consent to 
participate, but then develop one of these criteria, will be removed from the study) 
1. Participants in the intervention arm who fail to drink at least 50 ml of coffee 
2. Participants in the intervention arm who experience PONV prior to coffee 
consumption 
3. Participants in the control arm who experience PONV prior to or during consenting 
process (consenting process will stop if patient begins experiencing PONV) 
 
Sample Size Determination: A power analysis was conducted using G*Power (version 
3.1.9.2). The primary outcome variable (length of stay) was used with a small-medium 

effect size (0.3), power of 0.8, and level of significance 0.05.  It was determined that 139 
patients would be needed in each group, for a total sample size of 278 patients. 
Therefore, we plan to enroll approximately 300 patients to allow for missing data and 
patient withdrawals.   
 
• Data Collection 
Before the study begins, the study staff will provide education to all of the nurses 
working in the department involved in patient care.  This education will include 
information about the study design, the intervention, and the inclusion/exclusion 
criteria.  
 
Patients who meet the inclusion criteria will be approached by a member of the study 
team. The study team member will describe the study and answer any questions the 
patient has. If the patient is interested in enrolling in the study, they will be asked to 
review and sign an Informed Consent Form and a HIPAA Authorization Form. Personal 
health information, including name and date of birth, are recorded on the informed 
consent form and/or HIPAA Authorization Form.  
 
After the patient provides written informed consent, the study team member will 
remove the next envelope out of a box of prefilled and sealed opaque envelopes. The 
envelope will provide the Subject ID number to be used on all study-related 
documentation and the study Arm that the patient has been randomized to. 
 
• Intervention or experimental aspect of the study 
Patients randomized to Arm 1 will receive coffee in a Styrofoam cup at a temperature of 
125 degree Fahrenheit or less (Brown & Diller, 2008). Coffee will be offered to the 
patient in the PACU once the patient’s gag reflex has been restored following their 
procedure. Volume of estimated coffee consumption will be measured using a sample 
scale (with a maximum of 300mL of coffee offered). Patients randomized to Arm 2 will 
not be offered coffee while in the PACU.  
 
A data collection form will accompany patient to the PACU designating them as a study 
participant. Data will be recorded directly on this form and collected by a study team 
member after the patient is discharged. 
 
Independent variable:  
o Whether patient consumed part or all of the coffee in the PACU or not  
 
Dependent variables:  
o Primary outcome variable - Patient’s LOS in the PACU 
o Secondary outcome variables: 
▪ Whether the patient experienced PONV 
▪ Patient satisfaction 
 

Potential confounding variables:  
o How many minutes after entering PACU patient consumed coffee 
o How much coffee patient consumed 
 
 
• Statistical Analysis 
Data will be recorded on paper data collection forms with only subject ID and no 
identifiers. Data from these forms will be entered into a password protected database. 
Only study team members will have access to the database. No personal information 
will be entered into the electronic database. Data will undergo range checks when 
entered into the database, and quality control procedures will be performed to ensure 
accuracy of the data in the electronic database.  
 
Statistical analyses will be performed using SPSS statistical software.  Descriptive 
statistics (frequencies for categorical data; means and standard deviations and ranges 
for continuous data) will be used to describe the sample. The following analyses will be 
performed to address each hypothesis: 
 
Hypothesis 1: Patients who self-identify as coffee drinkers who receive coffee 
postoperatively will experience a shorter length of stay in the PACU compared to 
patients who self-identify as coffee drinkers and do not receive coffee postoperatively. 
To compare the effects of the intervention, an independent samples t-test will be 
used to compare mean length of stay in the PACU for patients who received 
coffee to the mean length of stay in the PACU among patients who did not 
receive coffee.  A level of significance of α=0.05 will be used.  
 
Hypothesis 2: Patients who self-identify as coffee drinkers who receive coffee 
postoperatively will experience a lower occurrence of postoperative nausea and 
vomiting in the PACU compared to patients who self-identify as coffee drinkers and do 
not receive coffee postoperatively. 
To compare the effects of the intervention, a Chi Square test will be used to 
compare occurrence of postoperative nausea and vomiting for patients who 
received coffee to patients who did not receive coffee.  A level of significance of 
α=0.05 will be used.   
 
Hypothesis 3: Patients who self-identify as coffee drinkers who receive coffee 
postoperatively will report higher patient satisfaction compared to patients who self-
identify as coffee drinkers and do not receive coffee postoperatively. 
To compare the effects of the intervention, an independent samples t-test will be 
used to compare mean patient satisfaction for patients who received coffee to 
the mean patient satisfaction among patients who did not receive coffee.  A level 
of significance of α=0.05 will be used.  
 
 

Ethical Considerations 
• Informed consent  
All study staff will complete CITI training. A study staff member will meet with 
potentially eligible patients and describe the study and answer any questions.  If the 
patient is interested and meets all the inclusion/exclusion criteria, the study staff will 
review the Informed Consent Form and HIPAA Authorization and obtain written 
informed consent.  Patients will receive a copy of their signed Informed Consent form 
and HIPAA Authorization.  
 
Informed Consent forms and HIPAA Authorizations will be stored in a locked cabinet 
that only study staff will have access to.  After the study closes, the signed Informed 
Consent forms and HIPAA forms will be boxed and sent to off-site storage and securely 
stored for 10 years.  At that time, the hard copy forms will be shredded.  
 
• Privacy information 
Personal identifiers will not be recorded on data collection forms or the electronic 
database of final data. Hard copy data collection forms will be stored in locked cabinets 
that only study staff will have access to.  Electronic data will be stored on a password-
protected folder on the U drive.  Only study staff will have access to the electronic 
study documents.  After data analysis and dissemination is completed, hard copy forms 
will be boxed and sent to secure storage for 10 years at which time they will be 
shredded.  After data analysis and dissemination, electronic data and forms will be de-
identified and transferred to a password-protected flash drive which will be sent to 
secure storage for 10 years at which time it will be destroyed.  
 
 
Cost/Budget 
There will be no costs to conduct this study and no additional charges to patients.   
 
Estimated Period of Time to Complete Study 
When will study begin? 
April 1, 2018 
Protocol Development 
Completed 
1 month 
Scientific Review 
2 weeks 
Admin Review Time 
2 weeks  
IRB Approval 
6 weeks 
Data collection 
3 months 
Data analysis 
2 months 
Presentation development 
(if applicable) 
1 month 
Manuscript Development 
(if applicable) 
3 months 

Journal submission process 
(if applicable) 
6 months 
Study closure 
1 month 
 
• When and how will results be disseminated? 
Results will be disseminated internally to the TriHealth perioperative leadership team and 
system-wide through the TriHealth Research Council.  Results will be disseminated nationally 
through presentation at a professional organization conference.  Finally, results will be 
disseminated nationally and internationally by publication in a relevant peer-reviewed journal. 
 
 
References 
 
Brown, F., & Diller, K.R. (2008). Calculating the optimum temperature for serving hot beverages. 
Burns, 34, 648-657. DOI: 10.1016/j.burns.2007.09.012 
 
Gungorduk, K., Ozdemir, I.A., Gungorduk, O., Gulseren, V., Gokcu, M., & Sanci, M. (2017). 
Effects of coffee consumption on gut recovery after surgery of gynecological cancer patients: a 
randomized controlled trial. American Journal of Obstetrics & Gynecology, 216, 14..e1 – 145.e7 
 
Muller, S.A., Rahbari, N.N., Schneider, F., Warschkow, R., Simon, T., von Frankenberg, M., Bork, 
U., Weitz, J., Schmied, B.M., & Buchler, M.W. (2012). Randomized clinical trial on the effect of 
coffee on postoperative ileus following elective colectomy. British Journal of Surgery, 99, 1530-
1538. 
 
Taylor, S. R., & Demmig-Adams, B. (2007). To sip or not to sip: The potential. Nutrition & Food 
Science, 37(6), 406-418.  
 
Warner, N.S., Warner, M.A., Schroeder, D.R., Sprung, J., & Weingarten, T.N. (2018). Effects of 
caffeine administration on sedation and respiratory parameters in patienst recovering from 
anesthesia. Bosnian Journal of Basic Medical Sciences, 18, 101-104.