Plasma, Fresh Frozen

Datasets entered into the TraumaRegister DGU® between 2002 and 2011 were retrieved for analysis. The inclusion criteria for the present study were age ≥16 years, primary admission, and complete datasets for SBP, HR and Glasgow Coma Scale as well as for BD upon ED admission. The SI was calculated for each individual patient by the ratio of HR to SBP.
Based upon previous observations by Zarzaur and colleagues [15 (link)], four groups of worsening SI were analyzed. Group I was defined a priori by SI <0.6 (no shock), group II by SI ≥0.6 to <1.0 (mild shock), group III by SI ≥1.0 to <1.4 (moderate shock) and group IV by SI ≥1.4 (severe shock). Analyses of vital signs, demographics and injury patterns as well as the therapeutic management such as transfusion rates, administration of fluids and the use of vasopressors were assessed for each SI group. Massive transfusion (MT) was defined by the administration of ≥10 blood products (including packed red blood cells, fresh frozen plasma and thrombocyte concentrates) until ICU admission. Coagulopathy was defined by a Quick’s value ≤70%, which is equivalent to International Normalized Ratio ≥1.3 [25 (link),26 (link)]. In accordance with the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference, sepsis was defined by the presence of a systemic inflammatory response syndrome as a result of a confirmed infectious process [27 (link)].
For the comparison of the novel SI-based classification, the four groups of worsening SI were compared with our recently introduced BD-based classification of hypovolemic shock [7 (link)]. Patients were therefore classified according to their SI at ED admission and their BD at ED admission. For each classificatory approach, transfusion requirements were compared within the four groups.

The demographic pre-, intra- and postoperative data of all patients (125 patients in the control group and 122 in the SPMD group) were collected in a Microsoft Excel spreadsheet (Microsoft 365 MSO, Version 2112, Redmond, USA) from medical files, intraoperative anesthesia, and perfusion charts. Variables were collected as follows: (i) Preoperative characteristics: age, sex, medical history including arterial hypertension, diabetes, stroke/transient ischemic attack (TIA), psychiatric disorders (e.g., depression, schizophrenia, dementia), chronic kidney disease, and the pulmonary disorders asthma and chronic obstructive pulmonary disease (COPD). (ii) Perioperative characteristics: Surgical procedure, American Society Anesthesiology (ASA) physical status classification system, simplified acute physiology score (SAPS II) on ICU admission, the classification as emergency surgery, times of surgery, CPB and aortic clamping, as well as the number of red blood cell (RBC) and fresh frozen plasma (FFP) transfusions administered intraoperatively.

All vital data were obtained from the prospective registry of the vital signs for surgical patients at Chungnam National University Hospital (CNUH IRB 2019-08-039), which uses a free data collection program (Vital recorder^{11 (link)} version 1.8, accessed at https://vitaldb.net, Seoul, Republic of Korea).
Other data collected from patient medical records included age, sex, body mass index (BMI), comorbidities (hypertension, diabetes, coronary artery disease, liver cirrhosis, chronic obstructive pulmonary disease, chronic renal impairment), Charlson comorbidity index, American Society of Anesthesiologists (ASA) physical status, type of surgery (general, gynecological, otolaryngological, plastic, or urological), emergency surgery, duration of anesthesia, intraoperative infusion of vasopressor (norepinephrine), intraoperative transfusion (red blood cells or fresh frozen plasma), intraoperative fluid input, and intraoperative opioid dose (remifentanil, μg kg^–1 min^–1).
Intraoperative PI and heart rate (HR) were monitored continuously using a disposable oximeter sensor (Nellcor™ Neonatal-Adult SpO₂ sensor, Covidien, Mansfield, MA, USA) and a patient monitor (Intellivue MX700 or MX800 [Philips, Boeblingen, Germany]) and recorded at a frequency of 1 Hz. Oximeter sensor was routinely attached to the index or third finger of the patient unless contraindicated or inaccessible. Blood pressure was measured continuously with an arterial catheter or intermittently at 5-min intervals using a noninvasive blood pressure cuff and recorded at a frequency of 1 Hz. Intra-arterial pressure was primarily used for analysis, if available. Data regarding inhalation anesthetics (agent type, end-tidal concentration [%]) were obtained from the anesthesia machines and recorded at a frequency of 0.2–0.25 Hz. All vital signs and records of inhalation agents were extracted as 10 s interval mean values. These data were filtered for errors in blood pressure, so that the mean arterial pressure (MAP) was > 20 mmHg and < 150 mmHg. To include periods only with proper administration of inhalation anesthetics in the analysis, a cut-off value of end-tidal concentration (the 25th percentile of the intraoperative end-tidal concentration) of the inhalation agent was determined for the vital records of each individual and filtered accordingly. For example, if the median intraoperative end-tidal concentration of sevoflurane was 1.3 volume % (25th to 75th percentile, 1.2% to 1.4%), then the cut-off was set at 1.2 volume % and only periods with end-tidal sevoflurane concentrations above this value were included in the analysis. Mean of PI values acquired for three minutes immediately before the initiation of the administration of inhalation anesthetics was considered baseline.