title: Continuous non-invasive arterial pressure measurement: evaluation of CNAP device during vascular surgery.
abstract: OBJECTIVE
  Standard non-invasive blood pressure (BP) monitoring is an intermittent, discontinuous procedure. Beat-to-beat BP monitoring requires invasive measurement via an arterial catheter and may be associated with serious complications. The Infinity CNAP SmartPod (Dräger Medical AG & Co. KG, Lübeck, Germany) has recently been proposed for non-invasive continuous beat-to-beat BP measurements. The present study was designed to compare BP obtained with the CNAP and with an invasive method in the operating room.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Twenty-five patients undergoing major vascular surgery were included. Systolic, mean and diastolic BP were monitored invasively (SAP, MAP and DAP respectively) and not invasively using the CNAP (CNAP-S, CNAP-M and CNAP-D respectively). Measurements were performed intraoperatively every minute during 1 hour.
  
  
  RESULTS
  One thousand and five hundred pairs of simultaneous CNAP and invasive BP measurements were obtained and 148 were eliminated. The range of BP measurements was 63-205 mmHg for SAP and 57-187 mmHg for CNAP-S, 38-143 mmHg for MAP and 43-142 mmHg for CNAP-M, 29-126 mmHg for DAP and 33-121 mmHg for CNAP-D. Bias and 95% limit of agreement between CNAP and invasive BP measurements were respectively 7.2 and -17.7 to 32.2 mmHg for SAP, -1.8 and -22.0 to 18.3 mmHg for MAP, and -7.5 and -27.3 to 12.4 mmHg for DAP. The percentage of CNAP measurements with a bias <10% with the arterial line was 69%, 86% and 91% for systolic, diastolic and mean pressures, respectively.
  
  
  CONCLUSIONS
  Despite low accuracy for SAP and DAP measurements, CNAP system seems more accurate for MAP measurement in patients undergoing vascular surgery.
authors.affiliation: Service d'anesthésie réanimation 1, hôpital Pellegrin, CHU de Bordeaux, place Amélie-Raba-Léon, 33076 Bordeaux cedex, France. matthieu.biais@chu-bordeaux.fr
authors.forename: M
authors.initials: M
authors.lastname: Biais
authors.forename: L
authors.initials: L
authors.lastname: Vidil
authors.forename: S
authors.initials: S
authors.lastname: Roullet
authors.forename: F
authors.initials: F
authors.lastname: Masson
authors.forename: A
authors.initials: A
authors.lastname: Quinart
authors.forename: P
authors.initials: P
authors.lastname: Revel
authors.forename: F
authors.initials: F
authors.lastname: Sztark
mesh_terms: D000368:Aged; D000768:Anesthesia, General; D001795:Blood Pressure Determination / Q000295:instrumentation*; D015924:Blood Pressure Monitors; D002138:Calibration; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation*; D009873:Operating Rooms; D016683:Supine Position; D014656:Vascular Surgical Procedures / Q000379:methods*