title: Intra-dialytic blood oxygen saturation (SO2): association with dialysis hypotension (the SOGLIA Study).
abstract: BACKGROUND
  Intradialytic hypotension (IDH) has a dramatic impact on the main outcomes of dialysis patients. Early warning of hemodynamic worsening during dialysis would enable preventive measures to be taken. Blood oxygen saturation (SO2) is used for hemodynamic monitoring in the critical care setting and may provide useful information about IDH onset.
  
  
  OBJECTIVE
  To evaluate whether short- and medium-term variations in the SO2signal (ST-SO2var, MT-SO2var,) during dialysis are a predictor of IDH.
  
  
  METHODS
  In this 3-month observational cohort study, 51 hypotension-prone chronic hemodialysis (HD) patients, with vascular access by arteriovenous fistula (AVF) or central venous catheter (CVC), were enrolled. Continuous non-invasive blood SO2was monitored (fc = 0.2 Hz) by an optical sensor on the arterial line of the extracorporeal circulation; blood pressure (every 30 min), symptoms and their time of appearance were noted. Predictive power of IDH was expressed by the area under curve (AUC) sensitivity and specificity based on intradialytic variations in SO2.
  
  
  RESULTS
  A total of 1290 HD sessions were analyzed. Overall, off-line ST-SO2varanalysis proved able to correctly predict IDH in 67 % of the sessions where IDH occurred. The best predictive performance was found in the presence of highly arterialized AVF (SO2> 95 %) (75 % sensitivity; AUC 0.825; p < 0.05). On the contrary, in sessions with CVC, IDH prediction proved more efficient by MT-SO2var(AUC 0.575; p = 0.01).
  
  
  CONCLUSIONS
  Intradialytic SO2variability could be a valid parameter to detect in advance the hemodynamic worsening that precedes IDH. Appropriate timely intervention could help prevent IDH onset.
authors: Nephrology, Dialysis, Hypertension, Teaching Hospital Policlinico S.Orsola-Malpighi, Bologna, Italy. elena.mancini@aosp.bo.it.
authors: E
authors: E
authors: Mancini
authors: Health Sciences and Technologies Interdepartmental Center for Industrial Research, University of Bologna, Cesena, Italy.
authors: C
authors: C
authors: Perazzini
authors: Renal, Dialysis and Transplantation Unit, Department of Emergency and Transplantation, University of Bari, Bari, Italy.
authors: L
authors: L
authors: Gesualdo
authors: Nephrology and Dialysis Department, I.R.C.C.S. "Casa Sollievo della Sofferenza", San Giovanni Rotondo, Italy.
authors: F
authors: F
authors: Aucella
authors: Nephrology and Dialysis Unit, Azienda Ospedaliera "Fatebenefratelli e Oftalmico", Milano, Italy.
authors: A
authors: A
authors: Limido
authors: Division of Nephrology and Dialysis, Azienda Ospedaliera di Montichiari, Brescia, Italy.
authors: F
authors: F
authors: Scolari
authors: Nephrology and Dialysis Unit, Ospedale Civile, Cirié, Turin, Italy.
authors: S
authors: S
authors: Savoldi
authors: Health Sciences and Technologies Interdepartmental Center for Industrial Research, University of Bologna, Cesena, Italy.
authors: M
authors: M
authors: Tramonti
authors: Scientific Affairs Bellco srl, Mirandola, Italy.
authors: L
authors: L
authors: Corazza
authors: Scientific Affairs Bellco srl, Mirandola, Italy.
authors: M
authors: M
authors: Atti
authors: Health Sciences and Technologies Interdepartmental Center for Industrial Research, University of Bologna, Cesena, Italy.|Department of Electrical, Electronic and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy.
authors: S
authors: S
authors: Severi
authors: Territorial Department of Nephrology and Dialysis, ASL 8, Cagliari, Italy.
authors: P
authors: P
authors: Bolasco
authors: Nephrology, Dialysis, Hypertension, Teaching Hospital Policlinico S.Orsola-Malpighi, Bologna, Italy.
authors: A
authors: A
authors: Santoro
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001166:Arteriovenous Shunt, Surgical; D005260:Female; D006801:Humans; D007022:Hypotension / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D006435:Renal Dialysis / Q000009:adverse effects*
chemical_list: D010100:Oxygen
keywords: Blood pressure; Dialysis hypotension; Hemodialysis; Monitoring; Oxygen; Oxygen saturation