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BACKGROUND Pupillometry monitoring under general anesthesia is based on the assumption that pupillary diameter variations reflect the adequacy of the provided analgesia to the intensity of the nociceptive surgical stimulus. The accurate interpretation of pupillometric data requires establishing clearly what the expected baseline unstimulated pupillary diameter at each specific level of hypnosis is. Opioids decrease pupillary diameter in a dose-dependent fashion. In contrast, the effects of hypnotic drugs on pupillary diameter are not well known. Our aim was to describe the potential relationship between propofol predicted effect-site concentrations (Cets) ranging from 1 to 3 µg/mL and pupillary diameter. METHODS Patients were randomized to receive propofol by target-controlled infusion at a predicted Cet of 1, 2, or 3 µg/mL (groups P1, P2, and P3, respectively). Pupillary diameter measurements were performed after 10 minutes of steady-state propofol infusion at the randomized Cet. No stimulation was performed during the study. Heart rate and bispectral index (BIS) were continuously recorded. RESULTS Forty patients were included: (13, 14, and 13 in groups P1, P2, and P3, respectively). Mean pupillary diameter was 5.7 mm (1 mm) in group P1, 4.8 mm (1.3 mm) in group P2, and 3.3 mm (0.8 mm) in group P3. Propofol had a dose-dependent effect on pupillary diameter (linear regression R = 0.45, P < .001). Pupillary diameter was positively correlated with the BIS (Spearman r = 0.75 [95% confidence interval (CI), 0.54 to -0.87] P < .001). CONCLUSIONS From 1 to 3 µg/mL of predicted Cet, propofol has a dose-dependent effect on pupillary diameter. Within this concentrations range, there is a positive correlation between BIS and pupillary diameter. The subcortical effect of propofol on pupillary diameter is correlated to its effect on the cortex. Studies assessing pupillary diameter as a marker of the nociception-antinociception balance should be performed in patients with a standardized depth of hypnosis.

Patients with systemic rheumatic diseases (SRDs) may require ICU management for SRD exacerbation or treatment-related infections or toxicities.This was an observational study at 10 university-affiliated ICUs in France. Consecutive patients with SRDs were included. Determinants of ICU mortality were identified through multivariable logistic analysis.Three hundred sixty-three patients (65.3% women; median age, 59 years [interquartile range, 42-70 years]) accounted for 381 admissions. Connective tissue disease (primarily systemic lupus erythematosus) accounted for 66.1% of SRDs and systemic vasculitides for 26.2% (chiefly antineutrophil cytoplasm antibodies-associated vasculitides). SRDs were newly diagnosed in 43 cases (11.3%). Direct admission to the ICU occurred in 143 cases (37.9%). Reasons for ICU admissions were infection (39.9%), SRD exacerbation (34.4%), toxicity (5.8%), or miscellaneous (19.9%). Respiratory involvement was the leading cause of admission (56.8%), followed by shock (41.5%) and acute kidney injury (42.2%). Median Sequential Organ Failure Assessment (SOFA) score on day 1 was 5 (3-8). Mechanical ventilation was required in 57% of cases, vasopressors in 33.9%, and renal replacement therapy in 28.1%. ICU mortality rate was 21.0% (80 deaths). Factors associated with ICU mortality were shock (OR, 3.77; 95% CI, 1.93-7.36), SOFA score at day 1 (OR, 1.19; 95% CI, 1.10-1.30), and direct admission (OR, 0.52; 95% CI, 0.28-0.97). Neither comorbidities nor SRD characteristics were associated with survival.In patients with SRDs, critical care management is mostly needed only in patients with a previously known SRD; however, diagnosis can be made in the ICU for 12% of patients. Infection and SRD exacerbation account for more than two-thirds of these situations, both targeting chiefly the lungs. Direct admission to the ICU may improve outcomes.

Background Patients undergoing free flap reconstruction after head and neck cancer may develop free flap complications. In the perioperative period, haemoglobin content and oxygen tissue saturation (StO2) measured directly on the free flap reflect peripheral tissue oxygenation. However, in this type of surgery, StO2 cannot always be applied directly or proximate to the free flap. The aim of this study was to assess the possible value of StO2 measured at the thenar eminence and other 24 hour perioperative factors on free flap complications. Methods Inclusion criteria corresponded to patients with head and neck cancer with free flap surgery in whom direct StO2 could not be monitored on the flap nor in its peripheral area. Patient characteristics and intraoperative data, such as haemoglobin and fluid management, were prospectively collected. StO2 was measured remotely on the thenar eminence. Data were collected for 24 hours and free flap complications were recorded for up to 15 days after surgery. Patients were thereafter classified into two groups: with or without free flap complications and the data were compared in consequence. Results Forty consecutive patients were prospectively included. Ten patients had postoperative free flap complications and were compared to the 30 other patients without complications. The haemoglobin level at the reperfusion of the flap: (AUC 0.80 [0.65–0.91], threshold 9.9 g/dL, P Conclusion In head and neck complex oncologic reconstructive surgery, haemoglobin and BMI were the most sensitive tools for predicting postoperative free flap complications, while thenar eminence StO2 was not.