Background: In recent years, reports have increased regarding patients treated with sodium-glucose cotransporter 2 inhibitors (SGLT2i) who develop severe ketoacidosis during the perioperative period. This systematic review aims to extrapolate precipitating factors from case reports of SGLT2i-associated perioperative ketoacidosis. Methods: Two independent researchers will search PubMed, EMBASE, and Web of Science, up to June 1, 2022, with no language restrictions, to identify reports of perioperative ketoacidosis associated with SGLT2i use. We will include case reports/series describing patients taking SGLT2i who developed ketoacidosis (defined as blood pH < 7.3 and blood or urine ketone positivity) pre-, intra-, or postoperatively up to 30 days following surgery. Patients for whom SGLT2i was newly prescribed postoperatively and those for whom the diagnosis of ketoacidosis does not fulfill our criteria will be excluded. Competing interest statement: Dr. Yasuda reports receiving grants from Ono Pharmaceutical and Mitsubishi Tanabe Pharma Corporation. Funding statement: The Japan Society for the Promotion of Science Grant-in-Aid for Scientific Research (C) (Grant Number 21K06676) funded this study.

Dr. Yasuda reports receiving grants from Ono Pharmaceutical and Mitsubishi Tanabe Pharma Corporation.

The Japan Society for the Promotion of Science Grant-in-Aid for Scientific Research (C) (Grant Number 21K06676) funded this study.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study will use ONLY openly available human data that were originally published as research papers.

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Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.

Yes

All data produced in the present study will be available upon reasonable request to the authors.