Randomized Controlled Trial Investigating the Impact of High-Flow Nasal Cannula Oxygen Therapy on Patients Undergoing Robotic-Assisted Laparoscopic Rectal Cancer Surgery, with a Post-Extubation Atelectasis as a Complication.

Background: Utilizing high-flow nasal cannula (HFNC) oxygen therapy may prevent the collapse of alveoli and improve overall alveolar ventilation. In this study, we aimed to investigate the impact of HFNC on postoperative atelectasis in individuals undergoing robotic-assisted laparoscopic surgery. Methods: Patients undergoing robotic-assisted laparoscopic surgery for rectal cancer were randomly assigned to the control or HFNC groups. After the surgical procedure was complete and the trachea was extubated, both groups underwent an initial lung ultrasound (LUS) scan. In the post-anesthesia care unit (PACU), the control group received conventional nasal cannula oxygen therapy, while the HFNC group received high-flow nasal cannula oxygen therapy. A second LUS scan was conducted before the patient was transferred to the ward. The primary outcome measured was the total LUS score at the time of PACU discharge. Results: In the HFNC group (n = 39), the LUS score and the incidence of atelectasis at PACU discharge were significantly lower compared to the control group (n = 39) [(5 vs 10, P < 0.001), (48.72% vs 82.05%, P = 0.002)]. None of the patients in the HFNC group experienced hypoxemia in the PACU, whereas six patients in the control group did (P = 0.03). Additionally, the minimum SpO2 value in the PACU was notably higher in the HFNC group compared to the control group [99 vs 97, P < 0.001]. Conclusion: Based on the results, HFNC improves the extent of postoperative atelectasis and decreases the occurrence of atelectasis in individuals undergoing robotic-assisted laparoscopic surgery for rectal cancer.

Bilirubin potentiates etomidate-induced sedation by enhancing GABA-induced currents after bile duct ligation.

OBJECTIVES: Our previous clinical trial showed that etomidate requirements to reach an appropriate level of anesthesia in patients with obstructive jaundice were reduced, which means that these patients are more sensitive to etomidate. However, the mechanism is still not completely clear. The present study was aimed to investigate the mechanism by which bilirubin facilitates etomidate induced sedation. METHODS: A bile duct ligation (BDL) rat model was used to simulate obstructive jaundice. Anesthesia sensitivity to etomidate was determined by the time to loss of righting reflex (LORR). Intrathecal injection of bilirubin was used to test the effects of bilirubin on etomidate induced sedation. The modulating effects of bilirubin on GABA responses were studied using the whole-cell patch clamp technique. RESULTS: The time to LORR induced by etomidate was significantly decreased in the BDL groups (p < 0.05), and unconjugated bilirubin in serum and cerebrospinal fluid (CSF) were markedly increased (p < 0.05). The time to LORR induced by etomidate was decreased after intrathecal injection of bilirubin (p < 0.05). A bilirubin concentration of 1.0 µM increased the GABA-induced currents of rat cortical pyramidal neurons (p < 0.05). Furthermore, 1.0 µM bilirubin enhanced GABA-induced currents modulated by etomidate (p < 0.05). CONCLUSIONS: Our results demonstrated that pathologic bilirubin in CSF could enhance etomidate induced sedation. The mechanism may be that bilirubin increase the GABA-induced currents of rat pyramidal neurons.

Safety of prone emergence from general endotracheal anesthesia in patients undergoing ERCP: a randomized controlled trial.

BACKGROUND: Conventional supine emergence and prone extubation from general endotracheal anesthesia (GEA) are associated with extubation-related adverse events (ERAEs). Given the minimally invasive nature of endoscopic retrograde cholangiopancreatography (ERCP) as well as the improved ventilation/perfusion matching and easier airway opening in the prone position, we aimed to assess the safety of prone emergence and extubation in patients undergoing ERCP under GEA. METHODS: Totally, 242 eligible patients were recruited and randomized into the supine extubation group (n = 121; supine group) and the prone extubation group (n = 121; prone group). The primary endpoint was the incidence of ERAEs during emergence, including hemodynamic fluctuations, coughing, stridor, and hypoxemia requiring airway maneuvers. The secondary endpoints included the incidence of monitoring disconnections, extubation time, recovery time, room exit time, and post-procedure sore throat. RESULTS: The incidence of ERAEs was significantly lower in the prone group compared with the supine group (8.3% vs 34.7%, OR = 0.17, 95% CI 0.18-0.56; P < 0.001). Moreover, the prone group demonstrated no monitoring disconnections, shorter extubation time and room exit time, faster recovery, and, lower frequency and milder sore throat after the procedure. CONCLUSIONS: For patients undergoing ERCP under GEA, compared with supine, prone emergence, and extubation had remarkably lower rates of EAREs and better recovery, and can maintain continuous monitoring and improve efficiency.

Effect of electroacupuncture on the repair of stress ulcer injury in neurocritical patients: A randomized clinical trial.

Background: Stress ulcer (SU) is one of the main causes of prolonged hospital stay, poor prognosis, and increased mortality in critically ill patients. This study aimed to investigate the effect of electroacupuncture (EA) on SU in patients with severe neurological diseases and explore its possible mechanisms. Methods: Taking patients with SU in adult neurocritical care as the research object, they were randomly divided into the EA group and the control group. Through the perioperative EA intervention, the following indicators were documented: main observation indicator (the effective rate of SU treatment), secondary observation indicators (gastric juice pH, gastric juice occult blood test, and stool occult blood test), related mechanisms [repair factors trefoil factor family 2 (TFF2), vascular endothelial growth factor (VEGF), and heat shock protein 70 (HSP70)], complications during hospitalization, and intensive care unit (ICU) stay time. Results: Compared with the control treatment, EA increased the effective rate of SU treatment (85.4% for the EA group, 57.5% for the control group, risk difference: 27.9% (95% CI: 8.3%-45.1%); P < 0.01). EA increased the success rate of gastric juice pH treatment on days 1, 2, and 3 (P < 0.01 for day 1, P < 0.05 for days 2 and 3). EA lowered the positive rate of gastric occult blood test on days 1 and 3 (all P-values < 0.05) and the positive rate of fecal occult blood test on day 3 (P < 0.05). EA also reduced the ICU stay time (P < 0.01) and total hospitalization time (P < 0.05). Compared with day 0, all serum repair factors (VEGF, HSP70, and TFF2) of both groups significantly increased on days 1, 3, and 5 (all P-values < 0.01). Compared with the control group, VEGF in the EA group was increased on days 3 and 5 (all P-values < 0.01); HSP70 was increased on days 1, 3, and 5 (P < 0.05 for day 1, P < 0.01 for days 3 and 5); and TFF2 was increased on days 1, 3, and 5 (all P-values < 0.01). Conclusion: Electroacupuncture promoted the repair of SU damage in severe neurological disease, and its effect was related to enhancing the expression of gastric mucosal repair factors. Clinical trial registration: [https://www.chictr.org.cn/showprojen.aspx?proj=127012], identifier [ChiCTR2100046701].

[Electroacupuncture improves long-term survival of myocardial infarction mice by promoting myocardial angiogenesis and inhibiting ventricular remodeling].

OBJECTIVE: To investigate the mechanism of electroacupuncture (EA) in improving the long-term survival rate of mice after myocardial infarction by promoting angiogenesis and inhibiting ventricular remodeling. METHODS: A total of 102 male C57BL/6 mice were randomly divided into sham operation, model and EA groups (n=34 /group). The myocardial infarction model was established by permanent ligation of the anterior descending branch of the left coronary artery. Beginning from the 3rd day after ligation, EA (2 Hz/20 Hz) was applied to bilateral "Neiguan" (PC6) and "Ximen" (PC4) for 30 min, once a day for 28 days. The survival rate in 140 d was recorded and the left ventricular ejection fraction (EF) calculated by using echocardiography after the treatment. The left cardiac ventricular tissue was cut into sections to be stained with Masson's trichrome, wheat germ agglutinin (WGA) or α-smooth muscle actin (α-SMA) immunohistochemistry method, followed by measuring the collagen area in the marginal region of myocardial infarction and calculating the collagen volume fraction (for assessing the severity of myocardial fibrosis), measuring the sectional area of cardiomyocytes (for assessing the degree of myocardial hypertrophy), and ob-serving the newborn blood vessels and calculating the ratio of neovascularization area (for assessing the state of angiogenesis). The expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α protein in the boundary area of myocardial infarction were detected by Western blot. RESULTS: After modeling, the survival rate, EF, and the thickness of the left cardiac ventricle were significantly decreased (P<0.01), whereas the percentage of collagen deposition area, sectional area of cardiomyocyte, percentage of angiogenesis area, and the expression levels of VEGF and HIF-1α proteins were significantly increased (P<0.01) in the model group relevant to the sham operation group. Compared with the model group, the survival rate, EF, the thickness of the left cardiac ventricle, the percentage of angiogenesis area, and the expression levels of VEGF and HIF-1α proteins were significantly increased (P<0.05, P<0.01), while the percentage of collagen deposition area and the sectional area of the cardiomyocyte were considerably decreased in the EA group (P<0.01, P<0.05). CONCLUSION: EA of PC6 and PC4 can significantly improve the cardiac function and long-term survival rate in mice with myocardial infarction, which may be related to its functions in up-regulating the expression of HIF-1α and VEGF to promote angiogenesis and in inhibiting ventricular remodeling.

Effects of perioperative transcutaneous electrical acupoint stimulation on monocytic HLA-DR expression in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass: study protocol for a double-blind randomized controlled trial.

BACKGROUND: Cardiac surgery involving cardiopulmonary bypass (CPB) is known to be associated with a transient postoperative immunosuppression. When severe and persistent, this immune dysfunction predisposes patients to infectious complications, which contributes to a prolonged stay in the intensive care unit (ICU), and even mortality. Effective prevention and treatment methods are still lacking. Recent studies revealed that acupuncture-related techniques, such as electroacupuncture and transcutaneous electrical acupoint stimulation (TEAS), are able to produce effective cardioprotection and immunomodulation in adult and pediatric patients undergoing cardiac surgery with CPB, which leads to enhanced recovery. However, whether perioperative application of TEAS, a non-invasive technique, is able to improve immunosuppression of the patients with post-cardiosurgical conditions is unknown. Thus, as a preliminary study, the main objective is to evaluate the effects of TEAS on the postoperative expression of monocytic human leukocyte antigen (-D related) (mHLA-DR), a standardized "global" biomarker of injury or sepsis-associated immunosuppression, in patients receiving on-pump coronary artery bypass grafting (CABG). METHODS: This study is a single-center clinical trial. The 88 patients scheduled to receive CABG under CPB will be randomized into two groups: the group receiving TEAS, and the group receiving transcutaneous acupoint pseudo-electric stimulation (Sham TEAS). Expression of mHLA-DR serves as a primary endpoint, and other laboratory parameters (e.g., interleukin [IL]-6, IL-10) and clinical outcomes (e.g., postoperative infectious complications, ICU stay time, and mortality) as the secondary endpoints. In addition, immune indicators, such as high mobility group box 1 protein and regulatory T cells will also be measured. DISCUSSION: The current study is a preliminary monocentric clinical trial with a non-clinical primary endpoint, expression of mHLA-DR, aiming at determining whether perioperative application of TEAS has a potential to reverse CABG-associated immunosuppression. Although the immediate clinical impact of this study is limited, its results would inform further large-sample clinical trials using relevant patient-centered clinical outcomes as primary endpoints. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02933996. Registered on 13 October 2016.

Evaluation of efficacy of transcatheter arterial chemoembolization for hepatocellular carcinoma using magnetic resonance diffusion-weighted imaging.

Although the efficacy of transcatheter arterial chemoembolization (TACE) has been recommended as first-line therapy for nonsurgical patients with hepatocellular carcinoma (HCC), it is difficult to accurately predict the efficacy of TACE. Therefore, this study evaluated the efficacy of TACE for HCC using magnetic resonance (MR) diffusion-weighted imaging (DWI). A total of 84 HCC patients who received initial TACE were selected and assigned to the stable group (n=39) and the progressive group (n=45). Before TACE treatment, a contrast-enhanced MR scan and DWI (b=300, 600, and 800 s/mm2) were performed on all patients. The modified response evaluation criteria in solid tumors were used for evaluation of tumor response. Receiver operating characteristic curve was employed to predict the value of apparent diffusion coefficient (ADC) for TACE efficacy. The ADC values of HCC patients in the progressive group were higher than those in the stable group at different b-values (b=300, 600, and 800 s/mm2) before TACE treatment. The area under the curve of ADC values with b-values of 300, 600, and 800 s/mm2 were 0.693, 0.724, and 0.746; the threshold values were 1.94×10-3 mm2/s, 1.28×10-3 mm2/s, and 1.20×10-3 mm2/s; the sensitivity values were 55.6%, 77.8%, and 73.3%; and the specificity values were 82.1%, 61.5%, and 71.8%, respectively. Our findings indicate that the ADC values of MR-DWI may accurately predict the efficacy of TACE in the treatment of HCC patients.

Vagal modulation of high mobility group box-1 protein mediates electroacupuncture-induced cardioprotection in ischemia-reperfusion injury.

Excessive release of high mobility group box-1 (HMGB1) protein from ischemic cardiomyocytes activates inflammatory cascades and enhances myocardial injury after reperfusion. Here we report evidence that electroacupuncture of mice at Neiguan acupoints can inhibit the up-regulation of cardiac HMGB1 following myocardial ischemia and attenuate the associated inflammatory responses and myocardial injury during reperfusion. These benefits of electroacupuncture were partially reversed by administering recombinant HMGB1 to the mice, and further potentiated by administering anti-HMGB1 antibody. Electroacupuncture-induced inhibition of HMGB1 release was markedly reduced by unilateral vagotomy or administration of nicotinic receptor antagonist, but not by chemical sympathectomy. The cholinesterase inhibitor neostigmine mimicked the effects of electroacupuncture on HMGB1 release and myocardial ischemia reperfusion injury. Culture experiments with isolated neonatal cardiomyocytes showed that acetylcholine, but not noradrenaline, inhibited hypoxia-induced release of HMGB1 via a α7nAchR-dependent pathway. These results suggest that electroacupuncture acts via the vagal nerve and its nicotinic receptor-mediated signaling to inhibit HMGB1 release from ischemic cardiomyocytes. This helps attenuate pro-inflammatory responses and myocardial injury during reperfusion.

Electroacupuncture improves survival in rats with lethal endotoxemia via the autonomic nervous system.

BACKGROUND: Recent advances have indicated a complex interplay between the autonomic nervous system and the innate immune system. Targeting neural networks for the treatment of sepsis is being developed as a therapeutic strategy. Because electroacupuncture at select acupoints can modulate activities of the autonomic nervous system, we tested the hypothesis that electroacupuncture at specific acupoints could modulate systemic inflammatory responses and improve survival via its impact on the autonomic nervous system in a rat model of sepsis. METHODS: Sprague-Dawley male rats received electroacupuncture for 45 min before and at 1, 2, or 4 h after a lethal dose of intraperitoneal lipopolysaccharide injection (6 mg/kg). Outcomes included survival and systemic cytokine responses. Also, the possible roles of neural circuitry, including the hypothalamic-pituitary-adrenal axis and the autonomic nervous system, were evaluated. RESULTS: Electroacupuncture pretreatment at the Hegu acupoints significantly attenuate systemic inflammatory responses and improve survival rate from 20% to 80% in rats with lethal endotoxemia. Such a site-specific effect requires the activation of muscarinic receptors in the central nervous system, but not increasing central sympathetic tone. In the periphery synergistic, rather than independent, action of the sympathetic and parasympathetic systems is also necessary. CONCLUSIONS: Electroacupuncture pretreatment has a dramatic survival-enhancing effect in rats with lethal endotoxemia, which involves the activation of efferent neural circuits of the autonomic nervous system (e.g., cholinergic antiinflammatory pathway). This approach could be developed as a prophylactic treatment for sepsis or perioperative conditions related to excessive inflammation.

In vivo and ex vivo effects of propofol on myocardial performance in rats with obstructive jaundice.

BACKGROUND: Responsiveness of the "jaundiced heart" to propofol is not completely understood. The purpose of this study was to evaluate the effect of propofol on myocardial performance in rats with obstructive jaundice. METHODS: Male Sprague-Dawley rats (n = 40) were randomly allocated into two groups, twenty underwent bile duct ligation (BDL), and 20 underwent a sham operation. Seven days after the surgery, propofol was administered in vivo and ex vivo (Langendorff preparations). Heart rate, left ventricular end-systolic pressure (LVESP) left ventricular end-diastolic pressure (LVEDP), and maximal rate for left ventricular pressure rise and decline (± dP/dtmax ) were measured to determine the influence of propofol on the cardiac function of rats. RESULTS: Impaired basal cardiac function was observed in the isolated BDL hearts, whereas in vivo indices of basal cardiac function (LVESP and ± dP/dt) in vivo were significantly higher in rats that underwent BDL compared with controls. With low or intermediate concentrations of propofol, these indices of cardiac function were within the normal physiologic range in both groups, and responsiveness to propofol was unaffected by BDL. When the highest concentration of propofol was administrated, a significant decline in cardiac function was observed in the BDL group. CONCLUSIONS: In rats that underwent BDL, basal cardiac performance was better in vivo and worse ex vivo compared with controls. Low and intermediate concentrations of propofol did not appear to impair cardiac function in rats with obstructive jaundice.

Remifentanil preconditioning reduces hepatic ischemia-reperfusion injury in rats via inducible nitric oxide synthase expression.

BACKGROUND: Opioid preconditioning against ischemia reperfusion injury has been well studied in myocardial and neuronal tissues. The objective of this study was to determine whether remifentanil could attenuate hepatic injury and to investigate the mechanisms. METHODS: A rat model of hepatic ischemia reperfusion injury and a hepatocyte hypoxia reoxygenation (HR) injury model were used, respectively, in two series of experiments. Remifentanil was administered before ischemia or hypoxia and the experiments were repeated with previous administration of naloxone, L-arginine and N-ω-nitro-L-arginine methyl ester, a nonselective opioid receptor antagonist, a nitric oxide donor, and nitric oxide synthase (NOS) inhibitor, respectively. Serum aminotransferase, cytokines, and hepatic lipid peroxidation were measured. Histopathology examination and apoptotic cell detection were assessed. For the in vitro study, cell viability, intracellular nitric oxide, apoptosis, and NOS expression were evaluated. RESULTS: Remifentanil and L-arginine pretreatment reduced concentrations of serum aminotransferases and cytokines, decreased the concentrations of hepatic malondialdehyde and myeloperoxidase activity, and increased superoxide dismutase, nitric oxide, and inducible NOS expression in vivo. Decreased histologic damage and apoptosis were also seen in these two groups. These changes were prevented by previous administration of N-ω-nitro-L-arginine methyl ester but not naloxone. There was an increase in inducible NOS protein expression but not endogenous NOS in remifentanil and L-arginine pretreated groups compared with control, naloxone, and N-ω-nitro-L-arginine methyl ester groups. CONCLUSION: Pretreatment with remifentanil can attenuate liver injury both in vivo and in vitro. Inducible NOS but not opioid receptors partly mediate this effect by exhausting reactive oxygen species and attenuating the inflammatory response.

Decreased hepatic peroxisome proliferator-activated receptor-γ contributes to increased sensitivity to endotoxin in obstructive jaundice.

AIM: To investigate the role of hepatic peroxisome proliferator-activated receptor-γ (PPAR-γ) in increased susceptibility to endotoxin-induced toxicity in rats with bile duct ligation during endotoxemia. METHODS: Male Sprague-Dawley rats were subjected to bile duct ligation (BDL). Sham-operated animals served as controls. DNA binding were determined by polymerase chain reaction, Western blotting analysis, and electrophoretic mobility shift assay, respectively. BDL and sham-operated rats received a non-lethal dose of intraperitoneal lipopolysaccharide (LPS) injection (3 mg/kg, i.p.). Additionally, the potential beneficial effects of the PPAR-γ agonist rosiglitazone were determined in BDL and sham-operated rats treated with a non-lethal dose of LPS. Survival was assessed in BDL rats treated with a non-lethal dose of LPS and in sham-operated rats treated at a lethal dose of LPS (6 mg/kg, i.p.). RESULTS: PPAR-γ activity in rats undergoing BDL was significantly lower than in the sham-controls. Hepatic PPAR-γ gene expression was downregulated at both the mRNA and protein levels. In a parallel group, serum levels of pro-inflammatory cytokines were nearly undetectable in the sham-operated rats. When challenged with a non-lethal dose of LPS (3 mg/kg), the BDL rats had approximately a 2.4-fold increase in serum IL-6, a 2.7 fold increase in serum TNF-α, 2.2-fold increase in serum IL-1 and 4.2-fold increase in serum ALT. The survival rate was significantly lower as compared with that in sham-operated group. Additionally, rosiglitazone significantly reduced the concentration of TNF-α, IL-1ß, IL-6 and ALT in sham-operated rats, but not in BDL rats, in response to LPS (3 mg/kg). Also, the survival was improved by rosiglitazone in sham-operated rats challenged with a lethal dose of LPS, but not in BDL rats, even with a non-lethal dose of LPS (3 mg/kg). CONCLUSION: Obstructive jaundice downregulates hepatic PPAR-γ expression, which in turn may contribute to hypersensitivity towards endotoxin.

[Fluorescence characterization of leachate organic matter in 717 resin adsorption process].

Synchronous fluorescence spectroscopy and 3-dimensional excitation emission matrices spectra (3DEEM) were used to study the composition variation of dissolved organic matter (DOM) in landfill leachate in the adsorption process with 717 resin. The synchronous fluorescence spectra showed fluorescence intensities of longer wavelength went down greatly while those of shorter wavelength went up in the first 10 min, then there were little changes. 3DEEM results indicated that there were two fulvic-like fluorescence peaks, whose intensities decreased dramatically, the peak intensities ratio (I(UV)/I(Vis)) also decreased, and the blue shifts of emission wavelengths took place obviously with the time rising. It was indicated that the adsorption rate of DOM by 717 resin was fast, and the main adsorbed DOM had higher molecular weight and higher degree of complexity, which was potential to facilitate subsequent bio-treatment.

Baroreflex sensitivity is impaired in patients with obstructive jaundice.

BACKGROUND: Obstructive jaundice is associated with enhanced susceptibility to hypotensive shock, renal failure, and toxic effects of endotoxin, which results in high perioperative morbidity and mortality. Since the normal arterial baroreflex function is necessary for hemodynamic homeostasis and improving survival in sepsis, this study aimed to determine whether baroreflex sensitivity was impaired in jaundiced patients. METHODS: Thirty-five patients with obstructive jaundice scheduled for surgery were included, and 30 nonjaundiced patients served as controls. A modified Oxford pharmacologic technique was used for evaluating baroreflex sensitivity immediately before the surgery. Potential factors that may affect baroreflex sensitivity in jaundice, such as liver biochemistry, plasma concentrations of methionine-enkephalin, atrial natriuretic peptide and nitrate, were also measured. RESULTS: Patients with obstructive jaundice had decreased sensitivity in both the sympathetic and vagal components of the baroreflex, as compared with the controls (P < 0.01). There was a significant inverse correlation between plasma atrial natriuretic peptide concentration and decreased sympathetic baroreflex sensitivity in the jaundiced group (r = -0.44, P = 0.008). CONCLUSIONS: Baroreflex sensitivity is impaired in patients with obstructive jaundice, which may contribute to their enhanced susceptibility to the well-known perioperative complications. The underlying mechanisms for such a change may be associated with an increased level of plasma atrial natriuretic peptide.

Isoflurane preserves energy balance in isolated hepatocytes during in vitro anoxia/reoxygenation.

AIM: To investigate the protective effect of isoflurane on energy balance in isolated hepatocytes during in vitro anoxia/reoxygenation, and to compare isoflurane with halothane. METHODS: Hepatocytes freshly isolated from fed rats were suspended in Krebs-Henseleit buffer, and incubated in sealed flasks under O(2)/CO(2) or N(2)/CO(2) (95%/5%, V/V) for 30 or 60 min, followed by 5 or 10 min of reoxygenation, with an added volatile anesthetic or not. ATP, ADP, and adenosine monophosphate in hepatocytes were determined by high performance liquid chromatography, and energy charge was calculated. RESULTS: During 30 min of anoxia, the energy charge and total adenine nucleotide steadily increased with the isoflurane dose from 0 to 2 minimum alveolar anesthetic concentration (MAC), then decreased from 2 to 3 MAC. In short incubations (30-35 min) at 1 MAC isoflurane, energy charge modestly decreased during anoxia, which was partially prevented by isoflurane and completely reversed by reoxygenation, and total adenine nucleotide did not decrease. In long incubations (60-70 min), both energy charge and total adenine nucleotide greatly decreased during anoxia, with partial and no reversal by reoxygenation, respectively. Isoflurane partly prevented decreases in both energy charge and total adenine nucleotide during anoxia and reoxygenation. In addition, 1 MAC isoflurane obviously increased ATP/ADP, which could not be changed by 1 MAC halothane. CONCLUSION: Isoflurane partially protects isolated hepatocytes against decreases in both energy charge and total adenine nucleotide during short (reversible) or long (irreversible) anoxia.

Awakening concentration of desflurane is decreased in patients with obstructive jaundice.

BACKGROUND: Some studies suggest that behavioral complications of cholestasis, such as fatigue and pruritus, may be associated with altered neurotransmission in the brain. Because inhaled anesthetics primarily act on ion channels and receptors on the neuronal cell membrane and alter synaptic transmission in the central nervous system, it is possible that altered sensitivity to inhaled anesthetics may occur in cholestatic patients. Therefore, the authors compared the minimum alveolar concentration (MAC)-awake of desflurane in obstructive jaundiced patients with the MACawake in nonjaundiced patients. METHODS: Patients underwent inhalational induction of anesthesia with desflurane. MACawake was determined in each patient by observing the response to a verbal command (open eyes on request). An end-tidal anesthetic concentration was maintained at an initial target level of 1.4% for 15 min before a command. If a positive response was observed, the concentration of desflurane was increased by 0.1% and again kept constant for 15 min. The verbal command was then continued. This process was repeated until an end-tidal concentration was reached at which the patient did not respond to command. The anesthetic concentration midway between the value permitting the response and that just preventing the response was defined as MACawake for each patient. RESULTS: The MACawake of desflurane for patients with obstructive jaundice (1.78 +/- 0.19%) was significantly less than those observed for the control group (2.17 +/- 0.25%; P < 0.001) and correlated significantly with serum total bilirubin (r = -0.67, P = 0.0004). CONCLUSIONS: The MACawake of desflurane is reduced in obstructive jaundiced patients compared with nonjaundiced controls.