{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T14:31:00Z","timestamp":1786113060921,"version":"build-2736575974"},"reference-count":29,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T00:00:00Z","timestamp":1785888000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["22K10211"],"award-info":[{"award-number":["22K10211"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    Postoperative nausea and vomiting (PONV) is a frequent and serious complication after surgery. PONV also reduces patient satisfaction with surgery under spinal anesthesia and increases medical costs due to prolonged hospitalization. The purpose of this study is to apply artificial intelligence (AI) machine learning analysis to identify risk factors for PONV in patients undergoing surgery with spinal anesthesia. This retrospective study used artificial intelligence to analyze data of adult patients (aged \u226520 years) who underwent surgery under spinal anesthesia at Tohoku University Hospital from January 1, 2010 to December 31, 2022. To evaluate PONV, patients who experienced nausea and\/or vomiting or used antiemetics within 24 hours after surgery were extracted from postoperative medical records. The selected data were analyzed after propensity score matching with patients who did not experience PONV. We created an ensemble model for predicting the probability of PONV using five machine learning algorithms: random forest, gradient boosting machine, k-nearest neighbor, multilayer perceptron, and decision tree. Data were available for 4,574 patients. We performed propensity score matching and selected 538 patients for analysis (269 in the PONV group and 269 in the non-PONV group). The use of postoperative fentanyl was identified as the strongest contributor to PONV, followed by duration of surgery, body mass index (BMI), total urine output, and duration of anesthesia. The identified risk factors were female sex, BMI\u2009&lt;\u200925 kg\/m\n                    <jats:sup>2<\/jats:sup>\n                    , and duration of surgery (&lt; 60 min), duration of anesthesia (&lt; 100 min), cesarean section, use of postoperative fentanyl, administration of fentanyl\/ morphine into the spinal arachnoid, and puncture level of epidural anesthesia (Th7\u201312) were identified as anesthesia\/surgery-related risk factors. We used machine learning AI to evaluate risk factors for PONV after spinal anesthesia. We identified several patient-related and anesthesia\/surgery-related risk factors for PONV. The AI analysis used in this study was accurate enough to identify risk factors for PONV during spinal anesthesia and may provide sufficient evidence for predicting PONV.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0333162","type":"journal-article","created":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T17:28:51Z","timestamp":1785950931000},"page":"e0333162","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Machine learning-based prediction of postoperative nausea and vomiting after spinal anesthesia: A retrospective observational study"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1466-6228","authenticated-orcid":true,"given":"Hiroshi","family":"Hoshijima","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomo","family":"Miyazaki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shinichiro","family":"Omachi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daisuke","family":"Konno","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5748-6302","authenticated-orcid":true,"given":"Shigekazu","family":"Sugino","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8708-6852","authenticated-orcid":true,"given":"Masanori","family":"Yamauchi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toshiya","family":"Shiga","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kentaro","family":"Mizuta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,5]]},"reference":[{"issue":"24","key":"pone.0333162.ref001","doi-asserted-by":"crossref","first-page":"2441","DOI":"10.1056\/NEJMoa032196","article-title":"A factorial trial of six interventions for the prevention of postoperative nausea and vomiting","volume":"350","author":"CC Apfel","year":"2004","journal-title":"N Engl J Med"},{"issue":"2","key":"pone.0333162.ref002","doi-asserted-by":"crossref","first-page":"411","DOI":"10.1213\/ANE.0000000000004833","article-title":"Fourth consensus guidelines for the management of postoperative nausea and vomiting","volume":"131","author":"TJ Gan","year":"2020","journal-title":"Anesth Analg"},{"issue":"4","key":"pone.0333162.ref003","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1093\/oxfordjournals.bja.a013471","article-title":"Acupressure and prevention of nausea and vomiting during and after spinal anaesthesia for caesarean section","volume":"84","author":"D Harmon","year":"2000","journal-title":"Br J Anaesth"},{"issue":"11","key":"pone.0333162.ref004","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1001\/jama.1966.03100110075019","article-title":"Spinal (subarachnoid) block. A review of 11,574 cases","volume":"195","author":"DC Moore","year":"1966","journal-title":"JAMA"},{"issue":"11","key":"pone.0333162.ref005","doi-asserted-by":"crossref","first-page":"1208","DOI":"10.1093\/bja\/44.11.1208","article-title":"A study of factors concerned in emesis during spinal anaesthesia","volume":"44","author":"CK Ratra","year":"1972","journal-title":"Br J Anaesth"},{"issue":"10201","key":"pone.0333162.ref006","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1016\/S0140-6736(19)31721-0","article-title":"An artificial intelligence-enabled ECG algorithm for the identification of patients with atrial fibrillation during sinus rhythm: a retrospective analysis of outcome prediction","volume":"394","author":"ZI Attia","year":"2019","journal-title":"Lancet"},{"issue":"1","key":"pone.0333162.ref007","doi-asserted-by":"crossref","first-page":"5642","DOI":"10.1038\/s41467-019-13647-8","article-title":"Automated acquisition of explainable knowledge from unannotated histopathology images","volume":"10","author":"Y Yamamoto","year":"2019","journal-title":"Nat Commun"},{"issue":"6","key":"pone.0333162.ref008","doi-asserted-by":"crossref","first-page":"1835","DOI":"10.1109\/JBHI.2015.2471093","article-title":"A smartphone-based tool for assessing parkinsonian hand tremor","volume":"19","author":"N Kostikis","year":"2015","journal-title":"IEEE J Biomed Health Inform"},{"issue":"2","key":"pone.0333162.ref009","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1109\/TASE.2020.3022037","article-title":"Automatic detection of negative symptoms in schizophrenia via acoustically measured features associated with affective flattening","volume":"18","author":"F He","year":"2021","journal-title":"IEEE Trans Automat Sci Eng"},{"issue":"3","key":"pone.0333162.ref010","article-title":"HFS\u2010LightGBM: a machine learning model based on hybrid feature selection for classifying ICU patient readmissions","volume":"38","author":"Y Qiu","year":"2020","journal-title":"Expert Syst"},{"issue":"5","key":"pone.0333162.ref011","doi-asserted-by":"crossref","first-page":"1189","DOI":"10.1214\/aos\/1013203451","article-title":"Greedy function approximation: a gradient boosting machine","volume":"29","author":"JH Friedman","year":"2001","journal-title":"Ann Stat"},{"key":"pone.0333162.ref012","first-page":"2825","article-title":"Scikit-learn: machine learning in Python","volume":"12","author":"F Pedregosa","year":"2011","journal-title":"J Mach Learn Res"},{"issue":"10","key":"pone.0333162.ref013","doi-asserted-by":"crossref","first-page":"1095","DOI":"10.1073\/pnas.39.10.1095","article-title":"Stochastic games","volume":"39","author":"LS Shapley","year":"1953","journal-title":"Proc Natl Acad Sci U S A"},{"issue":"1","key":"pone.0333162.ref014","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1038\/s42256-019-0138-9","article-title":"From local explanations to global understanding with explainable AI for trees","volume":"2","author":"SM Lundberg","year":"2020","journal-title":"Nat Mach Intell"},{"key":"pone.0333162.ref015","article-title":"Attention is all you need","volume":"30","author":"A Vaswani","year":"2017","journal-title":"Adv Neural Inf Process Syst"},{"issue":"1","key":"pone.0333162.ref016","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1097\/00000542-199207000-00023","article-title":"Postoperative nausea and vomiting. Its etiology, treatment, and prevention","volume":"77","author":"MF Watcha","year":"1992","journal-title":"Anesthesiology"},{"issue":"6","key":"pone.0333162.ref017","doi-asserted-by":"crossref","first-page":"906","DOI":"10.1097\/00000542-199206000-00006","article-title":"Incidence and risk factors for side effects of spinal anesthesia","volume":"76","author":"RL Carpenter","year":"1992","journal-title":"Anesthesiology"},{"key":"pone.0333162.ref018","doi-asserted-by":"crossref","first-page":"101787","DOI":"10.1016\/j.eclinm.2022.101787","article-title":"Effects of opioids administered via intravenous or epidural patient-controlled analgesia after caesarean section: a network meta-analysis of randomised controlled trials","volume":"56","author":"C-Y Chang","year":"2022","journal-title":"EClinicalMedicine"},{"issue":"4","key":"pone.0333162.ref019","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1034\/j.1399-6576.2001.045004471.x","article-title":"Patient-controlled epidural analgesia versus continuous epidural analgesia after total knee arthroplasty","volume":"45","author":"M Silvasti","year":"2001","journal-title":"Acta Anaesthesiol Scand"},{"key":"pone.0333162.ref020","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.ejphar.2013.09.074","article-title":"Opioid induced nausea and vomiting","volume":"722","author":"HS Smith","year":"2014","journal-title":"Eur J Pharmacol"},{"issue":"2","key":"pone.0333162.ref021","doi-asserted-by":"crossref","first-page":"530","DOI":"10.1097\/00000542-200302000-00036","article-title":"Postoperative nausea and vomiting in regional anesthesia: a review","volume":"98","author":"A Borgeat","year":"2003","journal-title":"Anesthesiology"},{"issue":"1","key":"pone.0333162.ref022","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1186\/s12871-020-01154-z","article-title":"Risk of postoperative nausea and vomiting in hip and knee arthroplasty: a prospective cohort study after spinal anaesthesia including intrathecal morphine","volume":"20","author":"A Moraitis","year":"2020","journal-title":"BMC Anesthesiol"},{"issue":"7","key":"pone.0333162.ref023","doi-asserted-by":"crossref","first-page":"817","DOI":"10.1007\/s12630-020-01582-y","article-title":"The effect of intravenous dexamethasone on postoperative nausea and vomiting after Cesarean delivery with intrathecal morphine: a randomized-controlled trial","volume":"67","author":"A Selzer","year":"2020","journal-title":"Can J Anaesth"},{"issue":"2","key":"pone.0333162.ref024","first-page":"160","article-title":"An increased body mass index is no risk factor for postoperative nausea and vomiting. A systematic review and results of original data","volume":"45","author":"P Kranke","year":"2001","journal-title":"Acta Anaesthesiol Scand"},{"issue":"2","key":"pone.0333162.ref025","doi-asserted-by":"crossref","first-page":"99","DOI":"10.4097\/kja.22237","article-title":"Retrospective analysis of the incidence and predictors of postoperative nausea and vomiting after orthopedic surgery under spinal anesthesia","volume":"76","author":"J-W Ju","year":"2023","journal-title":"Korean J Anesthesiol"},{"issue":"6","key":"pone.0333162.ref026","doi-asserted-by":"crossref","first-page":"1612","DOI":"10.3390\/jcm9061612","article-title":"Effect of body mass index on postoperative nausea and vomiting: propensity analysis","volume":"9","author":"JH Kim","year":"2020","journal-title":"J Clin Med"},{"issue":"2","key":"pone.0333162.ref027","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1016\/j.jcgg.2012.04.006","article-title":"Being older as a risk factor for vomiting in those undergoing spinal anesthesia","volume":"3","author":"L-W Hung","year":"2012","journal-title":"J Clin Gerontol Geriatr"},{"issue":"1","key":"pone.0333162.ref028","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1111\/anae.14080","article-title":"International consensus statement on the management of hypotension with vasopressors during caesarean section under spinal anaesthesia","volume":"73","author":"SM Kinsella","year":"2018","journal-title":"Anaesthesia"},{"issue":"1","key":"pone.0333162.ref029","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1097\/00000542-198201000-00019","article-title":"Method of ephedrine administration and nausea and hypotension during spinal anesthesia for cesarean section","volume":"56","author":"S Datta","year":"1982","journal-title":"Anesthesiology"}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0333162","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T17:28:56Z","timestamp":1785950936000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0333162"}},"subtitle":[],"editor":[{"given":"Ilhem","family":"Berrou","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,8,5]]},"references-count":29,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8,5]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0333162","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,5]]}}}