The Incremental Risk of Intraoperative Fentanyl on PONV

Study Overview
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Brief Summary
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The aim of this quality control study is to describe the presence and intensity of postoperative nausea and vomiting (PONV) and its correlation with intraoperative fentanyl dosing. Additionally, the investigators will examine pain scores.

Detailed Description
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The primary aims of this quality control study are: to determine whether there is an independent association between the intraoperative administration of fentanyl (both as a continuous and categorical variable) and PONV within 24 postoperative hours determine whether or not the intraoperative fentanyl amount can be used to successfully restratify patients for PONV beyond the simplified Apfel score for PONV All required data is collected in regular daily practice. The following variables will be assessed by univariable models: Preoperative variables (e.g. patient characteristics) Surgical/Anesthesia variables (e.g. type/length of surgery, antiemetics) Outcome variables (PONV, worst pain as delineated in the outcomes section), Intraoperative fentanyl measured 1) as a continuous variable and 2) by predefined limits of 0 to 0.2mg, >0.2-0.5mg, >0.5 to 0.8mg, and >8mg. Finally for the multivariable model, the investigators will adjust for confounders, specifically for sex (m/f), history (Hx) of PONV (y/n), Hx of motion sickness (y/n), current smoker (y/n), age (years), expected duration of surgery (min; >60 min), postoperative opioids (y/n), the use of preemptive PONV Therapy (0,1,2 medications), propofol vs. inhalative agents (y/n), and surgery type (3 kinds) from the patient's electronic record. In the event that insufficient event rates are observed, we will collapse the variables into the simplified Apfel score to assess the independent value of fentanyl in predicting PONV. In addition to a logistic model as delineated above, we will conduct the following: receiver operating characteristic (ROC) curves of the logistic model without fentanyl, with fentanyl (continuous), and with fentanyl (categorical). additionally, ROCs of a simplified model using the Apfel score, the Apfel score with fentanyl (continous), and the Apfel score with fentanyl (categorical) will be made. Comparison of area under the receiver operating characteristics(AUROCs) by DeLong net reclassification improvement (NRI) of both the logistic model with and without fentanyl as well as the Apfel score with and without fentanyl To assess pain and administered fentanyl, we will examine pain scores by the numeric rating scale (NRS).

Official Title
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The Incremental Risk of Intraoperative Fentanyl on PONV: A Modifiable Risk Without Drawbacks?

Conditions
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PONV

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: In-patients with an expected simplified Apfel score of 2 or higher, Aged >= 18 years, and Undergoing general anesthesia (with or without neuraxial or regional anesthesia.) in abdominal, gynecological or otorhinolaryngological surgery Exclusion Criteria: Outpatients Patients with chronic pain, defined as recurring pain requiring intermittent hospitalization or regular intake of pain medication. Non-opioid naïve patients, defined as a history of abuse or having taken opioids within the last 30 days

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Any postoperative nausea and/or vomiting (PONV) within 24 hours after surgery | postoperative nausea and/or vomiting (PONV) yes/no (either by chart or by patient confirmation) within 24 hours (or next morning discharge) | within 24 hours (or next morning discharge) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of postoperative vomiting events within 24 hours | Number of times vomiting (0, 1-2, >3 times; either by chart or by patient confirmation) within 24 hours (or next morning discharge) | within 24 hours (or next morning discharge) | 
| Any postoperative nausea and/or vomiting (PONV) while in the recovery room | Postoperative nausea and/or vomiting (PONV) yes/no (either by chart or by patient confirmation) while in recovery room | first two postoperative hours | 
| Worst pain, i.e. highest Numeric Rating Score (NRS) | highest / worst pain score within 24 hours / in recovery room (defined as above) | within 24 hours / in recovery room (first two postoperative hours) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Fentanyl, opioids