DOI: 10.5061/dryad.9zw3r22qj
title: Relationship between intraoperative drop in pulse pressure and minimum mean arterial pressure with postoperative length of stay according to main patients’ characteristics: A retrospective monocentric study

description: Intraoperative hypotension (IOH) is associated with organ failure. There
 is no consensus on the IOH definition, but the recommendations agree on a
 threshold of mean arterial pressure (MAP) between 60-70 mmHg. Prolonged
 postoperative length of stay (pLOS) is a surrogate for organ injuries. Our
 study focuses on the relationship between IOH and pLOS risk considering
 the main patient characteristics (sex and age) using
 a retrospective single-centre cohort study of adult patients
 having received general anesthesia for a scheduled non-cardiac surgical
 procedure. pLOS was defined as a LOS higher than the median value (main
 outcome). Relationships between the IOH variables selected from a previous
 study (difference between the larger and smaller pulse pressure values
 (DropPP), minimal MAP (MinMAP), and cumulative time pulse pressure spent
 above 61mmHg (CumTimePP&gt;61mmHg) and the risk of pLOS are
 represented by knotted linear splines. Our study examined 9,516
 patients. The relationship between DropPP and pLOS risk was pseudolinear
 with no activation threshold (slope 0.29-0.52%/mmHg). For MinMAP, this
 relationship describes an activation threshold at 73 mmHg below which the
 association is linear (slope -0.64%/mmHg). For CumTimePP&gt;61, the
 risk of pLOS rapidly rises (initial slope 8.39%/min) up to a saturation
 threshold at two minutes. Women had a lower pLOS risk and IOH threshold.
 Older patients had a higher pLOS risk and did not exhibit an IOH
 threshold. The IOH threshold (MAP&lt;73 mmHg) is consistent
 with the existing literature. The variability of PP as well as age and sex
 are key parameters in pLOS risk.
description: This retrospective single-centre study was managed in a tertiary
 academic private non-profit hospital. Patients were collectively informed
 (by means of posters) that their data could be used for research purposes,
 on condition that the data were anonymized. This information included the
 necessary information to enable them to refuse their participation. As a
 result of this procedure, the need for consent was waived by the local
 Ethics Committee which approved this retrospective study. Authors had no
 access to information that could identify individual participants during
 or after data collection. Patient characteristics and
 preoperative medications were collected from Cesare™, a computerized
 software for preoperative anesthetic evaluation (Bow Médical, 80440 Boves,
 France). Centricity Anesthesia software was used to collect intraoperative
 variables (GE Healthcare, 78 530 Buc, France). The length of stay and
 in-hospital mortality were obtained by questioning the health data
 warehouse.
description: # Relationship between intraoperative drop in pulse pressure and minimum
 mean arterial pressure with postoperative length of stay according to main
 patients’ characteristics in a retrospective monocentric study
 [https://doi.org/10.5061/dryad.9zw3r22qj](https://doi.org/10.5061/dryad.9zw3r22qj) ## Description of the data and file structure #### The demography table contains the main patients' characteristics. (Demography.csv)  id_data | Patient number  surgery | 1: general; 2: lung; 3:neurosurgery; 4: urology; 5: vascular; 6: gynecology; 7: ENT  age | 1: below 65 years; 2: 65 years and more  sex | 1:M; 2: F  los | Length of postoperative stay (days)  time_quartile | Quartile of surgery duration (absolute number)  median_Stay | Median length of stay (days)  Q3_Stay | Third quartile of the length of stay (days)  Q90_Stay | 90th percentile of the length of stay (days)  Short_IQR | Interquartile range of length of stay &lt;=1 (Q3-Q1) (days) #### The measurements table contains intraoperative blood pressure measurements. (Demography.csv)  id_data | Patient number Min_MAP | minimal value of mean arterial pressure (mmHg) Max_MAP | maximal value of mean arterial pressure (mmHg) Delta_MAP | Largest Drop in MAP during surgery (mmHg) Mean_MAP | Mean MAP (mmHg) Median_MAP | Median MAP (mmHg) std_MAP | standard deviation of MAP (mmHg) Var_MAP | MAP variability (absolute number) Cum_time*MAP*[XX] | cumulative time of mean arterial pressure below [XX] mmHg (minutes) Area_time*MAP*[XX] | cumulative area of mean arterial pressure below [XX] mmHg (absolute number) Min_PP | minimal value of pulse pressure (mmHg) Max_PP | maximal value of pulse pressure (mmHg) Delta_PP | Largest Drop in PP during surgery (mmHg) Mean_PP | Mean PP (mmHg) Median_PP | Median PP (mmHg) std_PP | standard deviation of PP (mmHg) Var_PP | PP variability (absolute number) Cum_time*PP*[XX] | cumulative time of pulse pressure below [XX] mmHg (minutes) Cum_area*PP*[XX] | cumulative area of pulse pressure below [XX] mmHg (absolute number) Min_S | minimal value of systolic arterial pressure (mmHg) Max_S | maximal value of systolic arterial pressure (mmHg) Delta_S | Largest Drop in S during surgery (mmHg) Mean_S | Mean S (mmHg) Median_S | Median S (mmHg) std_S | standard deviation of S (mmHg) Var_S | S variability (absolute number) Cum_time*S*[XX] | cumulative time of systolic arterial pressure below [XX] mmHg (minutes) Area_time*S*[XX] cumulative area of systolic arterial pressure below [XX] mmHg (absolute number) Min_D | minimal value of diastolic arterial pressure (mmHg) Max_D | maximal value of diastolic arterial pressure (mmHg) Delta_D | Largest Drop in diastolic arterial during surgery (mmHg) Mean_D | Mean diastolic arterial (mmHg) Median_D | Median diastolic arterial (mmHg) std_D | standard deviation of diastolic arterial (mmHg) Var_D | diastolic arterial variability (absolute number) Cum_time*D*[XX] | cumulative time of diastolic pressure below [XX] mmHg (minutes) Area_time*D*[XX] | cumulative area of diastolic pressure below [XX] mmHg (absolute number) ## Code/software NA ## Access information NA