{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,7]],"date-time":"2026-11-07T02:24:14Z","timestamp":1794018254791,"version":"4.8.0"},"reference-count":28,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,2]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>Subdural hematomas and hygromas (SDHs) are common complications in idiopathic normal pressure hydrocephalus (iNPH) patients with shunts. In this registry-based study, patients with shunted iNPH were screened nationwide to identify perioperative variables that may increase the risk of SDH.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS<\/jats:title>\n                    <jats:p>The Swedish Hydrocephalus Quality Registry was reviewed for iNPH patients who had undergone shunt surgery in Sweden in 2004\u20132014. Potential risk factors for SDH were recorded preoperatively and 3 months after surgery. Drug prescriptions were identified from a national pharmacy database. Patients who developed SDHs were compared with those without SDHs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>\n                      The study population consisted of 1457 patients, 152 (10.4%) of whom developed an SDH. Men developed an SDH more often than women (OR 2.084, 95% CI 1.421\u20133.058, p &lt; 0.001). Patients on platelet aggregation inhibitors developed an SDH more often than those who were not (OR 1.733, 95% CI 1.236\u20132.431, p = 0.001). At surgery, shunt opening pressures had been set 5.9 mm H\n                      <jats:sub>2<\/jats:sub>\n                      O lower in the SDH group than in the no-SDH group (109.6 \u00b1 24.1 vs 115.5 \u00b1 25.4 mm H\n                      <jats:sub>2<\/jats:sub>\n                      O, respectively, p = 0.009). Antisiphoning devices (ASDs) were used in 892 patients but did not prevent SDH. Mean opening pressures at surgery and the follow-up were lower with shunts with an ASD, without causing more SDHs. No other differences were seen between the groups.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>iNPH patients in this study were diagnosed and operated on in routine practice; thus, the results represent everyday care. Male sex, antiplatelet medication, and a lower opening pressure at surgery were risk factors for SDH. Physical status and comorbidity were not. ASD did not prevent SDH, but a shunt with an ASD allowed a lower opening pressure without causing more SDHs.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3171\/2019.10.jns191223","type":"journal-article","created":{"date-parts":[[2020,1,24]],"date-time":"2020-01-24T20:40:46Z","timestamp":1579898446000},"page":"668-677","source":"Crossref","is-referenced-by-count":11,"title":["Risk factors for developing subdural hematoma: a registry-based study in 1457 patients with shunted idiopathic normal pressure hydrocephalus"],"prefix":"10.3171","volume":"134","author":[{"given":"Johan","family":"Gasslander","sequence":"first","affiliation":[{"name":"Department of Pharmacology and Clinical Neuroscience, Ume\u00e5 University, Ume\u00e5;"},{"name":"Departments of Cardiology and Health, Medicine and Caring Services, Linkoping University, Vrinnevi General Hospital Norrk\u00f6ping; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nina","family":"Sundstr\u00f6m","sequence":"additional","affiliation":[{"name":"Department of Radiation Sciences, Ume\u00e5 University, Ume\u00e5, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anders","family":"Eklund","sequence":"additional","affiliation":[{"name":"Department of Radiation Sciences, Ume\u00e5 University, Ume\u00e5, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars-Owe D.","family":"Koskinen","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Clinical Neuroscience, Ume\u00e5 University, Ume\u00e5;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Malm","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Clinical Neuroscience, Ume\u00e5 University, Ume\u00e5;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"key":"b1","series-title":"ASA Physical Status Classification System Relative Value Guide","author":"American Society of Anesthesiologists","year":"2019","unstructured":"American Society of Anesthesiologists: ASA Physical Status Classification System Relative Value Guide. 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