Antiemetic prophylaxis with droperidol in morphine-based intravenous patient-controlled analgesia: a propensity score matched cohort study.

BACKGROUND: There are limited real-world data regarding the use of droperidol for antiemetic prophylaxis in intravenous patient-controlled analgesia (IV-PCA). This study aimed to evaluate the antiemetic benefits and sedation effects of droperidol in morphine-based IV-PCA. METHODS: Patients who underwent major surgery and used morphine-based IV-PCA at a medical center from January 2020 to November 2022 were retrospectively analyzed. The primary outcome was the rate of any postoperative nausea and/or vomiting (PONV) within 72 h after surgery. Propensity score matching was used to match patients with and without the addition of droperidol to IV-PCA infusate in a 1:1 ratio. Multivariable conditional logistic regression models were used to calculate adjusted odds ratios (aORs) with 95% confidence intervals (CIs). RESULTS: After matching, 1,104 subjects were included for analysis. The addition of droperidol to IV-PCA reduced the risk of PONV (aOR: 0.49, 95% CI: 0.35-0.67, p < 0.0001). The antiemetic effect of droperidol was significant within 36 h after surgery and attenuated thereafter. Droperidol was significantly associated with a lower risk of antiemetic uses (aOR: 0.58, 95% CI: 0.41-0.80, p = 0.0011). The rate of unintentional sedation was comparable between the patients with (9.1%) and without (7.8%; p = 0.4481) the addition of droperidol. Postoperative opioid consumption and numeric rating scale acute pain scores were similar between groups. CONCLUSIONS: The addition of droperidol to IV-PCA reduced the risk of PONV without increasing opiate consumption or influencing the level of sedation. However, additional prophylactic therapies are needed to prevent late-onset PONV.

Cigarette smoking, opioid consumption, and pain intensity after major surgery: An observational study.

BACKGROUND: Chronic exposure to nicotine may change pain perception and promote opioid intake. This study aimed to evaluate the putative effect of cigarette smoking on opioid requirements and pain intensity after surgery. METHODS: Patients who underwent major surgery and received intravenous patient-controlled analgesia (IV-PCA) at a medical center between January 2020 and March 2022 were enrolled. Patients' preoperative smoking status was assessed using a questionnaire by certified nurse anesthetists. The primary outcome was postoperative opioid consumption within 3 days after surgery. The secondary outcome was the mean daily maximum pain score, assessed using a self-report 11-point numeric rating scale, and the number of IV-PCA infusion requests within three postoperative days. Multivariable linear regression models were used to calculate the regression coefficient (beta) and 95% confidence interval (CI) for the association between smoking status and outcomes of interest. RESULTS: A total of 1162 consecutive patients were categorized into never smokers (n = 968), former smokers (n = 45), and current smokers (n = 149). Current smoking was significantly associated with greater postoperative opioid consumption (beta: 0.296; 95% CI, 0.068-0.523), higher pain scores (beta: 0.087; 95% CI, 0.009-0.166), and more infusion requests (beta: 0.391; 95% CI, 0.073-0.710) compared with never smokers. In a dose-dependent manner, smoking quantity (cigarette per day) was positively correlated with both intraoperative (Spearman's rho: 0.2207, p = 0.007) and postoperative opioid consumption (Spearman's rho: 0.1745, p = 0.033) among current smokers. CONCLUSION: Current cigarette smokers experienced higher acute pain, had more IV-PCA infusion requests, and consumed more opioids after surgery. Multimodal analgesia with nonopioid analgesics and opioid-sparing techniques, along with smoking cessation should be considered for this population.

Side-chain-bulk effects on the molecular packing and photovoltaic performance of benzotrithiophene-benzooxadiazole conjugated copolymers.

Two alternating donor-acceptor conjugated polymers, PBTTBO-C13 C11 and PBTTBO-C13 C8 , comprising 5-alkylbenzo[1,2-b:3,4-b':5,6-d'']trithiophene (BTT) as the donor and 4,7-bis(4-dodecylthien-2-yl)benzo[1,2,5]oxadiazole (BO) as the acceptor, with different alkyl side-chain architectures on their BTT units are synthesized, and their bulk heterojunction photovoltaic properties when blended with the fullerene PC71 BM are characterized. Even a slight change in the length of the alkyl chain of the BTT units influences the steric bulk to such a degree that it substantially affects the molecular packing of the polymers and the performance of their photovoltaic devices. The bulkier side chains of the polymer PBTTBO-C13 C11 not only prevent its crystallization, but also suppress its light-absorption coefficient relative to that of PBTTBO-C13 C8 , as evidenced by X-ray diffraction and UV/Vis absorption studies, presumably because of weakened intermolecular interactions. Moreover, the polymer bearing bulkier side chains, PBTTBO-C13 C11 , is less miscible with PC71 BM than PBTTBO-C13 C8 , and this characteristic determines the morphology of their annealed blended films, as shown by TEM studies. The best efficiency is obtained with a device containing an annealed PBTTBO-C13 C8 /PC71 BM (1/2 w/w) active layer that was maintained at 120 °C for 10 min, which shows a power conversion efficiency of 6.2 %, an open-circuit voltage of 0.75 V, a short-circuit current density of 12.6 mA cm(-2) , and a fill factor of 66 %.

Symmetry and coplanarity of organic molecules affect their packing and photovoltaic properties in solution-processed solar cells.

In this study we synthesized three acceptor-donor-acceptor (A-D-A) organic molecules, TB3t-BT, TB3t-BTT, and TB3t-BDT, comprising 2,2'-bithiophene (BT), benzo[1,2-b:3,4-b':5,6-d″]trithiophene (BTT), and benzo[1,2-b;4,5-b']dithiophene (BDT) units, respectively, as central cores (donors), terthiophene (3t) as π-conjugated spacers, and thiobarbituric acid (TB) units as acceptors. These molecules display different degrees of coplanarity as evidenced by the differences in dihedral angles calculated from density functional theory. By using differential scanning calorimetry and X-ray diffractions for probing their crystallization characteristics and molecular packing in active layers, we found that the symmetry and coplanarity of molecules would significantly affect the melting/crystallization behavior and the formation of crystalline domains in the blend film with fullerene, PC61BM. TB3t-BT and TB3t-BDT, which each possess an inversion center and display high crystallinity in their pristine state, but they have different driving forces in crystallization, presumably because of different degrees of coplanarity. On the other hand, the asymmetrical TB3t-BTT behaved as an amorphous material even though it possesses a coplanar structure. Among our tested systems, the device comprising as-spun TB3t-BDT/PC61BM (6:4, w/w) active layer featured crystalline domains and displayed the highest power conversion efficiency (PCE) of 4.1%. In contrast, the as-spun TB3t-BT/PC61BM (6:4, w/w) active layer showed well-mixed morphology and with a device PCE of 0.2%; it increased to 3.9% after annealing the active layer at 150 °C for 15 min. As for TB3t-BTT, it required a higher content of fullerene in the TB3t-BTT/PC61BM (4:6, w/w) active layer to optimize its device PCE to 1.6%.