The purpose of this study was to identify optimal target propofol and remifentanil concentrations to avoid a gag reflex in response to insertion of an upper gastrointestinal endoscope. Patients presenting for endoscopy received target-controlled infusions (TCI) of both propofol and remifentanil for sedation-analgesia. Patients were randomized to 4 groups of fixed target effect-site concentrations: remifentanil 1 ng•mL (REMI 1) or 2 ng•mL (REMI 2) and propofol 2 μg•mL (PROP 2) or 3 μg•mL (PROP 3). For each group, the other drug (propofol for the REMI groups and vice versa) was increased or decreased using the "up-down" method based on the presence or absence of a gag response in the previous patient. A modified isotonic regression method was used to estimate the median effective Ce,50 from the up-down method in each group. A concentration-effect (sigmoid Emax) model was built to estimate the corresponding Ce,90 for each group. These data were used to estimate propofol bolus doses and remifentanil infusion rates that would achieve effect-site concentrations between Ce,50 and Ce,90 when a TCI system is not available for use. One hundred twenty-four patients were analyzed. To achieve between a 50% and 90% probability of no gag response, propofol TCIs were between 2.40 and 4.23 μg•mL (that could be achieved with a bolus of 1 mg•kg) when remifentanil TCI was fixed at 1 ng•mL, and target propofol TCIs were between 2.15 and 2.88 μg•mL (that could be achieved with a bolus of 0.75 mg•kg) when remifentanil TCI was fixed at 2 ng•mL. Remifentanil ranges were 1.00 to 4.79 ng•mL and 0.72 to 3.19 ng•mL when propofol was fixed at 2 and 3 μg•mL, respectively. We identified a set of propofol and remifentanil TCIs that blocked the gag response to endoscope insertion in patients undergoing endoscopy. Propofol bolus doses and remifentanil infusion rates designed to achieve similar effect-site concentrations can be used to prevent gag response when TCI is not available.
There is paucity of data on the impact of surgical incision and analgesia on relevant outcomes. A retrospective STROBE-compliant cohort study was performed between July 2007 and August 2017 of patients undergoing lung transplantation. Gender, age, indication for lung transplantation, and the 3 types of surgical access (Thoracotomy (T), Sternotomy (S), and Clamshell (C)) were used, as well as 2 analgesic techniques: epidural and intravenous opioids. Outcome variables were: pain scores; postoperative hemorrhage in the first 24 hours, duration of mechanical ventilation, and length of stay at intensive care unit (ICU). Three hundred forty-one patients were identified. Thoracotomy was associated with higher pain scores than Sternotomy (OR 1.66, 95% CI: 1.01; 2.74, P: .045) and no differences were found between Clamshell and Sternotomy incision. The median blood loss was 800 mL [interquartile range (IQR): 500; 1238], thoracotomy patients had 500 mL [325; 818] (P < .001). Median durations of mechanical ventilation in Thoracotomy, Sternotomy, and Clamshell groups were 19 [11; 37] hours, 34 [IQR 16; 57.5] hours, and 27 [IQR 15; 50.5] hours respectively. Thoracotomy group were discharged earlier from ICU (P < .001). Thoracotomy access produces less postoperative hemorrhage, duration of mechanical ventilation, and lower length of stay in ICU, but higher pain scores and need for epidural analgesia.
Objectives The aim of this study was to determine the effects of escalation of respiratory support and prolonged postoperative invasive ventilation on patient-centered outcomes, and identify perioperative factors associated with these 2 respiratory complications. Design A retrospective cohort analysis of cardiac surgical patients admitted to the cardiothoracic intensive care unit (ICU) between August 2015 and January 2018. Escalation of respiratory support was defined as “unplanned continuous positive airway pressure,” “non-invasive ventilation,” or “reintubation” after surgery; prolonged invasive ventilation was defined as “invasive ventilation beyond the first 12 hours following surgery.” The primary endpoint was the composite of escalation of respiratory support and prolonged ventilation. Setting Tertiary cardiothoracic ICU. Participants A total of 2,098 patients were included and analyzed. Interventions None. Measurements and Main Results The composite of escalation of support or prolonged ventilation occurred in 509 patients (24.3%). Patients who met the composite had higher mortality (2.9% v 0.1%; p < 0.001) and longer median [interquartile range] length of ICU (2.1 [1.0-4.9] v 0.9 [0.8-1.0] days; p < 0.0001) and hospital (10.6 [8.0-16.0] v 7.2 [6.2-10.0] days; p < 0.0001) stay. Hypoxemia and anemia on admission to ICU were the only 2 factors independently associated with the need for escalation of respiratory support or prolonged invasive ventilation. Conclusions Escalation of respiratory support or prolonged invasive ventilation is frequently seen in cardiac surgery patients and is highly associated with increased mortality and morbidity. Hypoxemia and anemia on admission to the ICU are potentially modifiable factors associated with escalation of respiratory support or prolonged invasive ventilation.
The relationship between persistent postoperative cognitive decline and the more common acute variety remains unknown; using data acquired in preclinical studies of postoperative cognitive decline we attempted to characterize this relationship. Low capacity runner (LCR) rats, which have all the features of the metabolic syndrome, were compared postoperatively with high capacity runner (HCR) rats for memory, assessed by trace fear conditioning (TFC) on the 7th postoperative day, and learning and memory (probe trial [PT]) assessed by the Morris water-maze (MWM) at 3 months postoperatively. Rate of learning (AL) data from the MWM test, were estimated by non-linear mixed effects modeling. The individual rat's TFC result at postoperative day (POD) 7 was correlated with its AL and PT from the MWM data sets at postoperative day POD 90. A single exponential decay model best described AL in the MWM with LCR and surgery (LCR-SURG) being the only significant covariates; first order AL rate constant was 0.07 s(-1) in LCR-SURG and 0.16s(-1) in the remaining groups (p<0.05). TFC was significantly correlated with both AL (R=0.74; p<0.0001) and PT (R=0.49; p<0.01). Severity of memory decline at 1 week after surgery presaged long-lasting deteriorations in learning and memory.
17 October 2025 in American Journal of Transplantation