Remifentanil and perioperative glycaemic response in cardiac surgery: an open-label randomised trial

Effects and mechanisms of perioperative medications on the hypothalamic pituitary adrenal response to surgical injury: A narrative review

The adrenal gland is a vital endocrine organ, and adrenal steroid synthesis and secretion are closely regulated by the hypothalamic-pituitary-adrenal (HPA) axis in response to various stimuli. Surgery or trauma can activate the HPA axis and induce the secretion of cortisol. Different cortisol responses vary with the grade of surgery. Perioperative medications have the potential to decrease the cortisol level in the body, and both excessive and insufficient cortisol levels after surgery are disadvantageous. The effect of perioperative medications on the HPA response to surgery can be divided into three levels: "adrenal insufficiency (AI)", "stress response inhibition", and "uncertainty". The clinical presentation of AI includes fatigue, nausea, vomiting, abdominal pain, muscle cramps, hypotension, hypovolemic shock and prerenal failure, which may result in fatal consequences. Stress response inhibition can reduce postoperative complications, such as pain and cognitive dysfunction. This is protective to patients during perioperative and postoperative periods. The aim of the present review is to shed light on current evidence regarding the exact effects and mechanisms of perioperative medications on the HPA response to surgical injury and provide the applicable guidance on clinical anesthesia.

The prognosis of patients with postoperative hyperglycemia after Stanford type A aortic dissection surgery and construction of prediction model for postoperative hyperglycemia

Objective

The mortality of type A aortic dissection (TAAD) is extremely high. The effect of postoperative hyperglycemia (PHG) on the prognosis of TAAD surgery is unclear. This study aims to investigate the prognosis of patients with PHG after TAAD surgery and construct prediction model for PHG.

Methods

Patients underwent TAAD surgery from January 2016 to December 2020 in Xiangya Hospital were collected. A total of 203 patients were included and patients were divided into non PHG group and PHG group. The occurrence of postoperative delirium, cardiac complications, spinal cord complication, cerebral complications, acute kidney injury (AKI), hepatic dysfunction, hypoxemia, and in-hospital mortality were compared between two groups. Data from MIMIC-IV database were further applied to validate the relationship between PHG and clinical outcomes. The prediction model for PHG was then constructed using Extreme Gradient Boosting (XGBoost) analysis. The predictive value of selected features was further validated using patient data from MIMIC-IV database. Finally, the 28-days survival rate of patient with PHG was analyzed using data from MIMIC-IV database.

Results

There were 86 patients developed PHG. The incidences of postoperative AKI, hepatic dysfunction, and in-hospital mortality were significant higher in PHG group. The ventilation time after surgery was significant longer in PHG group. Data from MIMIC-IV database validated these results. Neutrophil, platelet, lactic acid, weight, and lymphocyte were selected as features for prediction model. The values of AUC in training and testing set were 0.8697 and 0.8286 respectively. Then, five features were applied to construct another prediction model using data from MIMIC-IV database and the value of AUC in the new model was 0.8185. Finally, 28-days survival rate of patients with PHG was significantly lower and PHG was an independent risk factor for 28-days mortality after TAAD surgery.

Conclusion

PHG was significantly associated with the occurrence of AKI, hepatic dysfunction, increased ventilation time, and in-hospital mortality after TAAD surgery. The feature combination of neutrophil, platelet, lactic acid, weight, and lymphocyte could effectively predict PHG. The 28-days survival rate of patients with PHG was significantly lower. Moreover, PHG was an independent risk factor for 28-days mortality after TAAD surgery.

Sternotomy Wound Infiltration With Liposomal Versus Plain Bupivacaine for Postoperative Analgesia After Elective Cardiac Surgery

OBJECTIVES

Poor pain control after cardiac surgery can be associated with postoperative complications, longer recovery, and development of chronic pain. The authors hypothesized that adding liposomal bupivacaine (LB) to plain bupivacaine (PB) will provide better and long-lasting analgesia when used for wound infiltration in median sternotomy.

STUDY DESIGN

Prospective, randomized, and double-blinded clinical trial.

SETTING

Single institution, tertiary care university hospital.

PARTICIPANTS

Adult patients who underwent elective cardiac surgery through median sternotomy.

INTERVENTIONS

A single surgeon performed wound infiltration of LB plus PB or PB into the sternotomy wound, chest, and mediastinal tube sites.

MEASUREMENTS AND MAIN RESULTS

Patients were followed up for 72 hours for pain scores, opioid consumption, and adverse events. Sixty patients completed the study for analysis (LB group [n = 29], PB group [n = 31]). Patient characteristics, procedural variables, and pain scores measured at specific intervals from 4 hours until 72 hours postoperatively did not reveal any significant differences between the groups. Mixed-model regression showed that the trend of mean pain scores at movement in the LB group was significantly (p = 0.01) lower compared with the PB group. Opioid consumption over 72 hours was not significantly different between the 2 groups (oral morphine equivalents; median [interquartile range], 139 [73, 212] mg in LB v 105 [54, 188] mg in PB, p = 0.29). Recovery characteristics and adverse events were comparable.

CONCLUSIONS

LB added to PB for sternotomy wound infiltration during elective cardiac surgery did not significantly improve the quality of postoperative analgesia.

Remifentanil inhibits the inflammatory response of BV2 microglia and protects PC12 cells from damage caused by microglia activation

Microglia acts as a critical player in neuroinflammation and neuronal injury. Remifentanil (Rem) has been reported to exert anti-inflammatory activity in several types of diseases. However, the role of Rem in microglia-mediated neuroinflammation is unclear. The present study was designed to investigate the effects of Rem against lipopolysaccharide (LPS)-activated BV2 microglial and PC12 cell induced by activated BV2 microglia. Cell proliferative ability was assessed with cell counting kit-8 assay and cellular morphology was observed. ELISA assay was used to measure the expressions of PGE2 and inflammatory factors. The contents of p-NF-KB p65, p-IKKα/β, and COX2 were evaluated with the aid of western blot. The levels of NO and iNOS were assessed with Griess assay, qRT-PCR, and western blot. In addition, Tunel assay and western blot were performed to assess cell apoptosis. The data revealed that Rem alleviated BV2 microglial morphological injury induced by LPS. Furthermore, Rem suppressed inflammatory releases, iNOS, NO and PGE2 stimulated by LPS in activated BV2 cells. Moreover, Rem suppressed PC12 cell injury, the generations of inflammatory factors and cell apoptosis triggered by inflammatory mediators secreted from activated BV2 cells. These results suggest that Rem exhibited anti-neuroinflammatory activity in protecting PC12 cells against injury derived from LPS-stimulated BV2 microglia.

Stress Hyperglycemia Is Independently Associated with Persistent Organ Failure in Acute Pancreatitis

BACKGROUND/AIMS

Stress hyperglycemia is common in critical illness but it has not been clearly studied in patients with acute pancreatitis (AP). This study aimed to investigate the specific blood glucose (BG) level that defines stress hyperglycemia and to determine the impact of stress hyperglycemia on clinical outcomes in AP patients.

METHODS

AP patients admitted ≤ 48 h after abdominal pain onset were retrospectively analyzed. Patients were stratified by pre-existing diabetes and stress hyperglycemia was defined using stratified BG levels for non-diabetes and diabetes with clinical outcomes compared.

RESULTS

There were 967 non-diabetic and 114 diabetic (10.5%) patients met the inclusion criteria and the clinical outcomes between these two groups were not significantly different. In non-diabetes, the cut-off BG level of ≥ 180 mg/dl was selected to define stress hyperglycemia with an 8.8-fold higher odds ratio for persistent organ failure (POF) (95% CI 5.4-14.3; P < 0.001). For diabetes, ≥ 300 mg/dl was selected with a 7.5-fold higher odds ratio for POF (95% CI 1.7-34.3; P = 0.009). In multivariable logistic regression, stress hyperglycemia was independently associated with POF, acute necrotic collection, major infection and mortality. The combination of BG and systemic inflammatory response syndrome (SIRS) score in predicting POF was better than SIRS or Glasgow score alone.

CONCLUSIONS

This study identifies a cut-off BG level of ≥ 180 mg/dl and ≥ 300 mg/dl was optimal to define stress hyperglycemia for non-diabetic and diabetic AP patients, respectively. There was a significant relationship between stress hyperglycemia and adverse clinical outcomes.

Remifentanil pretreatment ameliorates H/R-induced cardiac microvascular endothelial cell dysfunction by regulating the PI3K/Akt/HIF-1α signaling pathway

Restoration of blood supply through medical or surgical intervention is a commonly adopted method for acute myocardial ischemia, but is also a trigger for cardiac ischemia/reperfusion injury. Studies have shown that remifentanil (REM) displays cardioprotective effects. In this study, the effects of REM on HCMEC viability were examined before and after the induction of H/R using Cell Counting Kit-8 assays. Wound healing and Matrigel angiogenesis assays were performed to assess HCMEC migration and angiogenesis, respectively. Commercial kits and western blotting were used to determine the endothelial barrier function of H/R-stimulated HCMECs with or without REM treatment. The expression of PI3K/Akt/hypoxia-inducible factor-1α (HIF-1α) pathway-related proteins was detected by western blotting. After pre-treatment with PI3K/Akt, the effects of REM on H/R-induced HCMEC injury were examined. We found that pre-treatment with REM displayed no impact on HCMEC viability under normal conditions but noticeably improved cell viability following H/R. The migratory abilities and tube-like structure formations of H/R-stimulated HCMECs were both enhanced by REM in a concentration-dependent manner. REM also decreased the permeability of H/R-stimulated HCMECs and upregulated the expression of tight junction proteins. Furthermore REM increased the expression of PI3K/Akt/HIF-1α signaling-related proteins in HCMECs. Inhibition of PI3K/Akt rescued REM-enhanced HCMEC function under H/R condition. Therefore, the present study demonstrated that REM pretreatment ameliorated H/R-induced HCMEC dysfunction by regulating the PI3K/Akt/HIF-1α signaling pathway.

Mechanism and Management of Fentanyl-Induced Cough

Fentanyl-induced cough (FIC) often occurs after intravenous bolus administration of fentanyl analogs during induction of general anesthesia and analgesia procedure. The cough is generally benign, but sometimes it causes undesirable side effects, including elevated intra-abdominal, intracranial or intraocular pressure. Therefore, understanding the related mechanisms and influencing factors are of great significance to prevent and treat the cough. This paper reviews the molecular mechanism, influencing factors and preventive administration of FIC, focusing on the efficacy and side effects of various drugs in inhibiting FIC to provide some medical reference for anesthesiologists.

Intraoperative Remifentanil Infusion and Postoperative Pain Outcomes After Cardiac Surgery-Results from Secondary Analysis of a Randomized, Open-Label Clinical Trial

DESIGN

Report of secondary pain outcomes from a prospective, randomized, open-label clinical trial that compared remifentanil and fentanyl on perioperative hyperglycemic response in cardiac surgery.

SETTING

Single institution, tertiary university hospital.

PARTICIPANTS

The study comprised 116 adult elective cardiac surgical patients.

INTERVENTIONS

Participants were randomly assigned to receive either intermittent fentanyl boluses (F) or continuous remifentanil infusion (R) intraoperatively.

MEASUREMENTS AND MAIN RESULTS

Postoperative pain was evaluated with pain scores every 6 hours for 48 hours. Pain threshold to mechanical stimuli was measured around the sternotomy incision at 48 and 96 hours. The development of chronic pain was assessed using the numeric rating scale at 1, 3, 6, and 12 months after discharge. The final analysis included 106 patients. Pain scores and wound hyperalgesia were not significantly different postoperatively between the groups. The incidence of chronic pain at 3 months was comparable in both groups (61% in group F v 58% in group R; p = 0.79). Pain of more-than-mild degree was seen in 13 (32%) patients in group F and 8 (19%) in group R (p = 0.25) at 3 months. Median pain scores were not significantly different between the groups at 1, 3, 6, and 12 months after discharge from the hospital.

CONCLUSIONS

The present study's findings suggested that intraoperative remifentanil infusion does not significantly worsen pain outcomes in patients undergoing elective cardiac surgery.