bluuebunny/crossref_metadata_2025 huggingface dataset:
Induced mild hypothermia reduces mortality during acute inflammation in rats
Authors: Huet O. , Kinirons B. , Dupic L. , Lajeunie E. , Mazoit J. X. , Benhamou D. , Vicaut E. , Duranteau J.
Published: August 2010

Background:  Hypothermia has been proposed as a therapeutic possibility in brain trauma, cardiac arrest and hemorrhagic shock. Experimental studies have shown that hypothermia may act by modulating the inflammatory response during endotoxemia. This study was carried out to test whether hypothermia could protect rats from endotoxemic insult.

Methods:  After general anesthesia and oro‐tracheal intubation, Sprague–Dawley rats were randomly assigned to either a hypothermic group or normothermic group. In each group, rats received intraperitoneal lipopolysaccharide (LPS) (10 or 20 mg/kg). Blood samples were taken prior to and 2 h after LPS injection to measure blood gases, liver enzymes, muscular enzymes, tumor necrosis factor‐α (TNF‐α) and interleukin‐10 (IL‐10) plasma levels. After 2 h of hypothermia, the rats were extubated and brought back to their cages. The mortality rate was observed for 7 days following endotoxemia. In a second set of experiments, hypothermia was induced 1 h after endotoxemia (10 mg/kg of intraperitoneal LPS) and the mortality rate was observed for the following 7 days.

Results:  The survival rate was significantly increased in the hypothermic group relative to the normothermic group, regardless of LPS dose. This increased survival rate was also observed when hypothermia was induced 1 h after endotoxemia. In the hypothermic group, IL‐10 and the ΔIL‐10/ΔTNF‐α ratio were significantly increased relative to those in the normothermic group.

Conclusion:  Induced mild hypothermia reduces mortality during endotoxemia in rats. The modulation of the inflammatory response, with an increase in anti‐inflammatory cytokines, may be involved in this protective effect.
Oxygenation and release of inflammatory mediators after off‐pump compared with after on‐pump coronary artery bypass surgery
Authors: Rasmussen B. S. , Laugesen H. , Sollid J. , Grønlund J. , Rees S. E. , Toft E. , Gjedsted J. , Dethlefsen C. , Tønnesen E.
Published: August 2010

Background:  In a previous study, we showed that oxygenation was impaired for up to 5 day after conventional coronary artery bypass grafting (CABG). As cardiopulmonary bypass (CPB) may have a detrimental effect on pulmonary function, we hypothesized that coronary revascularization grafting without the use of CPB (OPCAB) would affect post‐operative oxygenation and release of inflammatory mediators less compared with CABG.

Methods:  Low‐risk patients scheduled for elective coronary revascularization were randomly assigned to one of two groups (CABG, n = 17 or OPCAB, n = 18). Two parameters of oxygenation, shunt (%) and ventilation‐perfusions mismatch, described as ΔPO2 (kPa), were estimated for up to 5 days post‐operatively. Systemic release of interleukin (IL)‐6, ‐8 and ‐10, C‐reactive protein (CRP) and neutrophils were measured in peripheral blood samples for up to 3 days post‐operatively. The lungs participation in the cytokine response was evaluated from mixed venous blood samples taken within the first 16 h post‐operatively.

Results:  OPCAB was followed by a higher shunt (P = 0.047), with no difference (P = 0.47) in the deterioration of ΔPO2 between the groups. OPCAB was followed by an attenuated systemic release of IL‐8 (P = 0.041) and IL‐10 (P = 0.006), while the release of IL‐6 (P = 0.94), CRP (P = 0.121) and neutrophils (P = 0.078) did not differ between the groups. Indications of an uptake of cytokines in the lungs were found after OPCAB.

Conclusions:  When comparing OPCAB with CABG, oxygenation was more affected and only part of the systemic inflammatory response was attenuated.
Mortality after discharge from the intensive care unit during the early weekend period: a population‐based cohort study in Denmark
Authors: Obel N , Schierbeck J , Pedersen L , Storgaard M , Pedersen C , Sørensen H. T. , Hansen B
Published: August 2010

Background:  As a result of a shortage of intensive care capacity, patients may be discharged prematurely early during weekends which may lead to an increased mortality and risk of readmission to intensive care units (ICU). We examined whether discharge from the ICU during the first part of the weekend was associated with an increased mortality and readmission to the ICU.

Methods:  The study was conducted at a university clinic of internal medicine and included all patients admitted for the first time to the ICU, and discharged alive in the period 1 January 2001 to 31 December 2005. Patients were divided in those discharged between 00.00 h Friday and 24.00 h Saturday (weekend group) and those discharged Sunday to Thursday (non‐weekend group). The main outcome was time from discharge from the ICU to the combined endpoint death or re‐admission to ICU which ever came first. We used Kaplan–Meier analysis and Cox’s proportional‐hazards regression to compute survival curves and risk ratio estimates.

Results:  There were 228 patients in the weekend group and 555 patients in the non‐weekend group. Crude and adjusted 28‐day risk ratio of the combined endpoint was 1.50 [95% confidence interval (CI): 1.15–1.97] and 1.43 (1.09–1.87) in the weekend group. Although an increased risk of death was observed in the weekend group immediately after discharge from the ICU, the difference in mortality between the two groups had disappeared after 2 years.

Conclusion:  Medical patients discharged from the ICU early in the weekends seem to have an increased mortality and risk of readmission to the ICU.
Effect of ropivacaine on endothelium‐dependent phenylephrine‐induced contraction in guinea pig aorta
Authors: Lin P. L. , Huang H. H. , Fan S. Z. , Tsai M. C. , Lin C. H. , Huang C. H.
Published: August 2010

Background:  Previous studies have shown that ropivacaine has biphasic vascular effects, causing vasoconstriction at low concentrations and vasorelaxation at high concentrations. This study was designed to examine the role of the endothelium during accidental intravascular absorption of ropivacaine, and to elucidate the mechanisms responsible.

Methods:  Isolated guinea pig aortic rings were suspended for isometric tension recording. The effects of ropivacaine on endothelium‐intact and endothelium‐denuded aortic rings were assessed. Endothelium‐intact aortic rings were pre‐contracted with phenylephrine before being exposed to ropivacaine and acetylcholine, in order to generate and compare concentration–response curves. In the absence and presence of yohimbine, propranolol, atropine, indometacin, NG‐nitro‐l‐arginine methyl ester (l‐NAME), 1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one (ODQ) or methylene blue, the contractile response induced by ropivacaine was assessed on endothelium‐intact aortic rings pre‐contracted with phenylephrine.

Results:  Ropivacaine (3 × 10−4 to 10−2 mol/l) produced vasoconstriction in endothelium‐denuded aortic rings, whereas no such response was observed in aortic rings with intact endothelium. In phenylephrine pre‐contracted intact aortic rings, ropivacaine induced a greater degree of vasorelaxation than did acetylcholine. Yohimbine, propranolol and atropine all failed to affect the relaxation responses induced by ropivacaine. However, pre‐treatment with indometacin (cyclo‐oxygenase inhibitor), l‐NAME (nitric oxide synthase inhibitor), methylene blue (soluble guanylyl cyclase inhibitor) or ODQ (soluble guanylyl cyclase inhibitor), significantly decreased the ropivacaine‐induced relaxation of endothelium‐intact aortic rings (3 × 10−4 to 10−2 mol/l).

Conclusions:  Ropivacaine elicits an endothelium‐dependent vasorelaxation in phenylephrine pre‐contracted aortic rings via the nitric oxide–cyclic guanosine 3′,5′‐monophosphate pathway and the prostaglandin system.
Administration of fentanyl before remifentanil‐based anaesthesia has no influence on post‐operative pain or analgesic consumption
Authors: LENZ H. , RAEDER J. , HOYMORK S. C.
Published: August 2010

Background: Remifentanil's short‐acting analgesic effect and the potential of producing hyperalgesia is a challenge to post‐operative pain control. This study investigated whether pre‐treating the patients with fentanyl before remifentanil‐based anaesthesia could reduce post‐operative pain or analgesic consumption.

Methods: One‐hundred patients admitted for anterior cruciate ligament repair were included in a double‐blind study. Propofol and remifentanil were used for general anaesthesia. Group Pre received fentanyl 1.5 μg/kg intravenously (IV) and Group Post placebo before the remifentanil infusion. At the end of surgery, Group Pre received 1.5 μg/kg and Group Post received 3.0 μg/kg. Patient‐controlled analgesia with fentanyl was used as analgesic rescue medication during the first 4 h post‐operatively. Oxycodone 5 mg orally was taken as needed during the subsequent 4–24‐h period.

Results: A mean dose of remifentanil 0.43 μg/kg/min was used for 90 min during surgery in both groups. There were no differences in the verbal rate scale (VRS) score or need of rescue analgesic medication between the groups during the first 4 h. Group Post had significantly less pain in the 4–24‐h period after surgery, with a median VRS score of ‘slight pain’ vs. ‘moderate pain’ in Group Pre (P<0.05). The oxycodone consumption was similar in both groups.

Conclusion: Pre‐treatment with fentanyl 1.5 μg/kg IV yielded no reduction in post‐operative pain or analgesic consumption after 90 min of remifentanil‐based anaesthesia with 0.43 μg/kg/min of remifentanil.
Chronic AT1‐receptor blockade does not alter cerebral oxygen supply/demand ratio during cardiopulmonary bypass in hypertensive patients
Authors: KOTTENBERG‐ASSENMACHER E. , MASSOUDY P. , JAKOB H. , PHILIPP T. , PETERS J.
Published: August 2010

Background: The angiotensin II receptor type 1 antagonist candesartan has been hypothesized to alter vasopressor requirements and brain–blood flow by changing cerebrovascular autoregulation. Therefore, we assessed the effects of a pre‐anaesthetic treatment course with candesartan on cerebral arterial‐jugular bulb oxygen content difference, middle cerebral artery blood velocity, and vasopressor requirements in hypertensive patients undergoing elective on‐pump coronary artery bypass graft surgery.

Methods: In a randomized, double‐blind, placebo‐controlled study, we evaluated the effects of candesartan (8 mg po/d, given for 6–8 days before surgery) in 35 hypertensive patients. The mean arterial pressure was maintained above 60 mmHg by bolus administration of phenylephrine, if required, and dosages were recorded.

Results: Candesartan did not significantly alter oxygen content difference across the cerebral circulation, mean middle cerebral artery blood velocity during cardiopulmonary bypass, or phenylephrine requirements either before (0.0067 μg/kg/min±0.0042 vs. 0.0056 μg/kg/min±0.0049, P=0.48) or during cardiopulmonary bypass (0.0240 μg/kg/min±0.0240 vs. 0.0250 μg/kg/min±0.0190, P=0.97) compared with placebo.

Conclusion: Thus, a 6–8‐day treatment course with candesartan does not alter global cerebral perfusion and oxygen supply/demand ratio during cardiopulmonary bypass, or vasopressor requirements in hypertensive patients undergoing on‐pump coronary artery bypass graft surgery, and no deleterious consequences of AT1‐receptor blockade were detected.
Time‐ and dose‐related regional fluxes of tissue‐type plasminogen activator in anesthetized endotoxemic pigs
Authors: NYBERG A. , JAKOB S. M. , SEEMAN‐LODDING H. , PORTA F. , BRACHT H. , BISCHOFBERGER H. , JERN C. , TAKALA J. , ÅNEMAN A.
Published: August 2010

Background: Acute endotoxinemia elicits an early fibrinolytic response. This study analyzes the effects of the dose and duration of endotoxin infusion on arterial levels of tissue‐type plasminogen activator (tPA) and pulmonary, mesenteric and hepatic plasma tPA fluxes.

Methods: Pigs were randomized to receive an acute, high‐dose (for 6 h, n=13, high ETX) or a prolonged, low‐dose (for 18 h, n=18, low ETX) infusion of endotoxin or saline vehicle alone (for 18 h, n=14, control). All animals were fluid resuscitated to maintain a normodynamic circulation. Systemic and regional blood flows were measured and arterial, pulmonary arterial, portal and hepatic venous blood samples were analyzed to calculate regional net fluxes of tPA. Plasma tumor necrosis factor (TNF‐α) levels were analyzed.

Results: Mesenteric tPA release and hepatic uptake increased maximally at 1.5 h in ETX groups related to dose. Maximal mesenteric tPA release [high ETX 612 (138–1185) μg/min/kg, low ETX 72 (32–94) μg/min/kg, median±interquartile range] and hepatic tPA uptake [high ETX −1549 (−1134 to −2194) μg/min/kg, low ETX −153 (−105 to −307) μg/min/kg] correlated to TNF‐α levels. Regional tPA fluxes returned to baseline levels at 6 h in both ETX groups and also remained low during sustained low ETX. No changes were observed in control animals.

Conclusions: Endotoxemia induces an early increase in mesenteric tPA release and hepatic tPA uptake related to the severity of endotoxemia. The time patterns of changes in mesenteric and hepatic tPA fluxes are similar in acute high‐dose endotoxemia and sustained low‐dose endotoxemia.
Laparoscopic vs. small incision cholecystectomy: Implications for pulmonary function and pain. A randomized clinical trial
Authors: KEUS F. , AHMED ALI U. , NOORDERGRAAF G. J. , ROUKEMA J. A. , GOOSZEN H. G. , VAN LAARHOVEN C. J. H. M.
Published: August 2010

Background: Upper abdominal surgery, including laparoscopic cholecystectomy (LC), is associated with post‐operative pulmonary dysfunction. LC has, by consensus, become the treatment of choice for symptomatic cholecystolithiasis. The small‐incision cholecystectomy (SIC), a procedure which does not require a pneumoperitoneum threatens to be lost to clinical practice even though there is evidence of equality. We hypothesized that the SIC technique should be equal and might even be superior to the LC when considering post‐operative pulmonary function due to the short incision length.

Methods: A single‐centre, randomized clinical trial was performed including patients scheduled for elective cholecystectomy. Pulmonary flow–volume curves were measured pre‐operatively, post‐operatively, and at follow up. Blood gas analyses were measured pre‐operative, in the recovery phase and on post‐operative day 1. Anaesthesia, analgesics, and peri‐operative care were standardized by protocol. Post‐operatively, patients and caregivers were blinded to the procedure.

Results: A total of 257 patients were analysed. There was one pulmonary complication (pneumonia) in the LC group. In both groups, similar reductions of approximately 20% in pulmonary function parameters occurred, with complete recovery to pre‐operative values. Patients in the SIC group consumed more analgesia when compared with the LC group without impact on blood gas analysis. Patients converted to a conventional open technique showed significant differences in six of the eight parameters in pulmonary function tests.

Conclusion: When evaluated with strict methodology and standardization of care, no clinically relevant differences were found between SIC and LC regarding pulmonary function. Our results suggest that the popularity of the laparoscopic technique cannot be attributed to pulmonary preservation.
Adrenal function in different subgroups of septic shock patients
Authors: SALGADO D. R. , ROCCO J. R. , ROSSO VERDEAL J. C.
Published: August 2010

Background: Relative adrenal insufficiency (RAI) is a common complication during septic shock and may be more frequent in specific subgroups. The main objectives of this study were to determine the adrenal function and the RAI incidence in different subgroups of septic shock patients considering: main admission categories (medical, elective or emergency surgery); source of infection; nosocomial or community‐acquired infections; gender, age <65 years or >65 years; and the presence or absence of neurological diseases, acute respiratory distress syndrome (ARDS) and bacteremia.

Methods: Prospective study in a medical–surgical ICU, including adults with septic shock, from May 2002 to May 2005. All patients had total serum cortisol measured at baseline and 60 min after a high‐dose ACTH test within the first 96 h of shock onset. RAI was defined as a serum cortisol increment after ACTH test (Δmax249) <90 μg/l.

Results: One hundred and two subjects were enrolled, and the overall RAI incidence was 22.5%. Patients with ARDS before ACTH test or bacteremia showed lower Δmax249 values than patients with ARDS after ACTH test (96 vs. 153 μg/l, P=0.02) or without bacteremia (140 vs. 175 μg/l, P=0.04). Multivariate regression analysis revealed that female gender, development of ARDS before ACTH test, and bacteremia were associated with greater RAI incidence. There was no difference in RAI incidence considering neurological diseases, age, type and source of infection and the main admission categories.

Conclusions: Female gender, bacteremia and early‐onset ARDS were variables independently associated with greater RAI incidence in septic shock patients. There was no difference in the RAI incidence concerning other subgroups.
Sonoclot analysis in elderly compared with younger patients undergoing coronary surgery
Authors: PLEYM H. , WAHBA A. , BJELLA L. , STENSETH R.
Published: August 2010

Background: The Sonoclot analyzer is a point‐of‐care method for assessment of the clotting mechanism in whole blood. The results are available within 20 min. The aim of the present study was to investigate whether repeated Sonoclot analyses could identify peri‐operative differences in hemostatic function between elderly and younger patients undergoing coronary artery bypass grafting (CABG). In addition, we investigated whether Sonoclot analyses could identify disturbances in hemostatic function leading to post‐operative bleeding.

Methods: Twenty‐five elderly and 25 younger patients undergoing CABG were included. Blood samples for Sonoclot analyses were drawn pre‐operatively, during surgery, and during the first 20 post‐operative hours. The Sonoclot variables sonACT, clot rate, time‐to‐peak, amplitude of the peak, and R3 were analyzed, and the results were compared between the two groups. Post‐operative blood loss volumes were recorded and correlated to the Sonoclot variables. The Sonoclot variables were also correlated to previously reported results on various hemostatic variables measured in the same patient population.

Results: There was a significant difference in sonACT between the two groups (P=0.018). There were no differences between the groups in any of the other Sonoclot variables. There were no significant correlations between any of the Sonoclot variables and post‐operative bleeding, or between the Sonoclot variables and other hemostatic variables.

Conclusions: The difference in sonACT between the two groups indicates a reduced hemostatic function in the elderly patients. However, repeated Sonoclot analyses were not able to identify more specific disturbances in hemostatic function, and did not predict increased post‐operative bleeding.
Pain management of opioid‐treated cancer patients in hospital settings in Denmark
Authors: LUNDORFF L. , PEUCKMANN V. , SJØGREN P.
Published: August 2010

Aim: To evaluate the performance and quality of cancer pain management in hospital settings.

Methods: Anaesthesiologists specialised in pain and palliative medicine studied pain management in departments of oncology and surgery. Study days were randomly chosen and patients treated with oral opioids were included. Information regarding pain aetiology and mechanisms, pain medications and opioid side effects were registered from the medical records and by examining patients. Pain intensity was assessed using the Brief Pain Inventory.

Results: In total, 59 cancer patients were included. In 49 (83%) patients pain aetiology was assessed by the physicians of the departments of oncology and surgery. In only 19 (32%) patients they assessed pain mechanisms. The median oral morphine dose was 120 mg/day (range: 10–720 mg/day). Seventy‐eight per cent of patients received opioids at adequate regular intervals according to the duration of action. In 88% of the patients supplemental short‐acting oral opioids were given on demand and the median supplemental oral dose was 16.5% of the daily dose. Seven patients with neuropathic pain received adjuvant drugs, whereas six patients with non‐neuropathic pain received adjuvant drugs. Regarding opioid side effects only constipation and nausea were treated in the majority of the patients. Average pain intensity in the last 24 h for the total number of patients (n=59) ≤5 cm was 88.1% (confidence interval 77.1–95.1).

Conclusion: Cancer pain was prevalent in opioid‐treated patients in hospital settings: however, focussing on average pain intensity, the outcome seems favourable compared with other countries. Pain mechanisms were seldom examined and adjuvant drugs were not specifically used for neuropathic pain. Opioid dosing intervals and supplemental opioid doses were most often adequate. However, opioid side effects were highly prevalent and most side effects were left untreated.
Less tongue engorgement with lateral placement of the Esophageal Tracheal Combitube
Authors: MOIED AHMED S. , RIZVI K. A. , KHAN R. M. , UZ ZAFAR M. , NADEEM A.
Published: August 2010

Background: The conventional technique of insertion and fixation of the Esophageal Tracheal Combitube™ (ETC) is occasionally associated with engorgement of the tongue. This study sought to evaluate the efficacy of an alternative placement technique in reducing the incidence of this complication.

Methods: Thirty ASA I and II adult patients posted for elective surgery under general anaesthesia lasting from 30 to 120 min were randomly divided into two groups (n=15, each). In Group A, the ETC was inserted and fixed in the midline. In Group B, the ETC was inserted along the angle of the mouth and was fixed at this lateral position. Intra‐operative occurrence of engorgement of the tongue, the time of such an occurrence and any complaints of post‐operative discomfort were recorded.

Results: The overall incidence of engorgement of the tongue in Group A patients (67%) was significantly more (P<0.01) as compared with Group B (17%). The incidence significantly increased (P<0.01) with an increase in the duration of surgery in both the groups. The engorgement persisted into the post‐operative period in three patients in Group A and resolved spontaneously in <15 min in each case.

Conclusion: Lateral insertion and fixation of the ETC is an easy, safe and effective method of preventing engorgement of the tongue associated with the use of this device without compromising a leak‐proof oropharyngeal cavity.
Rotational thrombelastometry for the bedside monitoring of recombinant hirudin
Authors: SUCKER C. , ZOTZ R. B. , GÖRLINGER K. , HARTMANN M.
Published: August 2010

Background: Recombinant hirudin is used as an alternative anticoagulant, particularly in patients with heparin‐induced thrombocytopenia type II. However, bedside monitoring for hirudin is not available. The present study aims to evaluate rotational thrombelastometry regarding its suitability to detect the effects of recombinant hirudin on whole blood coagulation. Hirudin was added to whole blood samples from healthy donors (n=5) and thrombelastometry variables resulting from activation of samples with tissue factor, ellagic acid, and ecarin were determined.

Methods: Hirudin (0.1–10 μg/ml) was added to citrated blood. Thereafter, rotational thrombelastometry was performed by initiating coagulation via recalcification and addition of tissue factor, ellagic acid, and ecarin, respectively, using the commercially available assays.

Results: In the absence of hirudin, clotting times (CT) induced by ellagic acid, tissue factor, and ecarin, respectively, were 141.7±18.0, 54.0±7.6, and 64.5±4.1 s. Increasing concentrations of hirudin led to dose‐dependent prolongation of the clotting time with the three activators. All assays were capable to detect hirudin concentrations in the range of 0.5–5 μg/ml. At a final hirudin concentration of 1 μg/ml, clotting time increased to 268.0±25.1, 84.0±9.3, and 107.5±9.9 s, respectively, with the above‐mentioned activators. The other thrombelastographic variables, including clot formation time, angle α, and maximum clot firmness, were not altered by hirudin at concentrations up to 5 μg/ml.

Conclusions: Our study demonstrates the suitability of rotational thrombelastometry to detect anticoagulant effects of recombinant hirudin.
Chronic pain after hysterectomy
Authors: BRANDSBORG B. , NIKOLAJSEN L. , KEHLET H. , JENSEN T. S.
Published: August 2010

Background: Chronic pain is a well‐known adverse effect of surgery, but the risk of chronic pain after gynaecological surgery is less established.

Method: This review summarizes studies on chronic pain following hysterectomy. The underlying mechanisms and risk factors for the development of chronic post‐hysterectomy pain are discussed.

Results and conclusion: Chronic pain is reported by 5–32% of women after hysterectomy. A guideline is proposed for future prospective studies.
Administration of milrinone before ischemia, in the presence of β‐blockade, to treat metabolic impairment and myocardial stunning in pigs
Authors: SIDI A. , MUEHLSCHLEGEL J. D. , KIRBY D. S. , LOBATO E. B.
Published: August 2010

Background: We examined effects of phosphodiesterase type III inhibition on regional myocardial metabolism and global left ventricular function, during ischemia, in the presence of β‐blockade.

Methods: Twenty‐three pigs were randomized and studied to completion in four groups: C, did not receive drugs; M, received 50 μg/kg milrinone; E, received esmolol (150 μg/kg/min); E+M, received both. The left anterior descending artery (LADa) was then occluded for 15 min, followed by a 60‐min reperfusion. Left ventricular (LV) function data obtained included LV pressures, cardiac output (CO), slope of end‐systolic pressure–volume relationship (Emax), and dP/dT. Blood lactate concentrations were obtained from the aorta, LADa, and vein at baseline, end of occlusion, and during early (5 min) and late (1 h) reperfusion.

Results: During ischemia, occlusion produced significant depression in LV dP/dT, Emax and concomitant elevation of LVEDP that persisted over early reperfusion in groups not treated with milrinone. After ischemia, measurements of CO were higher, with lower LVEDP and SVR; LV dP/dT and the Emax were higher, with lower LVEDP in the E+M group vs. the E group. Ischemic region lactate extraction during ischemia was better with E group vs. C group. Esmolol without or with milrinone was associated with nonsignificant lactate ischemic production during early reperfusion from baseline values.

Conclusion: We demonstrated that the pre‐emptive administration of milrinone before ischemia was associated with less ischemic hemodynamic effects, without worsening the ischemic metabolic process. The combination E+M diminished ischemic metabolic impairment, and preserved left ventricular function and baseline hemodynamics.
Propofol–fentanyl anaesthesia at high altitude: anaesthetic requirements and haemodynamic variations when compared with anaesthesia at low altitude
Authors: PURI G. D. , JAYANT A. , DORJE M. , TASHI M.
Published: August 2010

Background: There are few published accounts of anaesthesia delivery at high altitude. Natives at high altitude are known to have altered cardiorespiratory reserve. This study seeks to demonstrate the safety of propofol–fentanyl anaesthesia at high altitude titrated to the bispectral index (BIS) (3505 metres above sea level) in native highlanders. It also shows the differential effects of anaesthesia and surgery on the haemodynamics of such individuals as compared with individuals living at low altitude.

Methods: Fifteen consenting adults scheduled to undergo general surgical/orthopaedic procedures under general anaesthesia using fentanyl, and propofol infusions titrated to the BIS along with nitrous oxide in oxygen after intubation, were recruited in the high‐altitude arm. Their anaesthesia record was compared with retrospective data from low altitude with respect to anaesthetic requirements, recovery after anaesthesia and the haemodynamic responses to surgical stress.

Results: The high‐altitude dwellers required significantly larger doses of propofol at anaesthetic induction (2.31±0.64 vs. 1.41±0.24 mg/kg, P<0.0001) and thereafter to maintain designated BIS than their low‐altitude counterparts (6.22±1.14 vs. 4.61±1.29 mg/kg/h, P<0.01). They, however, had uneventful and short recovery times. The high‐altitude population also had significantly lower baseline heart rates (72±9.83 vs. 88±12.1, P<0.04) as also the heart rate responses to noxious stimulation such as direct laryngoscopy or skin incision (P<0.04, P<0.005, respectively).

Conclusions: High‐altitude dwellers require significantly larger amounts of intravenous anaesthetic propofol. Heart rate at rest as also the heart rate responses to surgical stress were significantly attenuated at high altitude.
Use of ultrasound guidance and contrast enhancement: a study of continuous infraclavicular brachial plexus approach*
Authors: DHIR S. , GANAPATHY S.
Published: August 2010

Purpose: We describe our experience of combining the use of ultrasound (US) guidance with contrast enhancement and peripheral nerve stimulation for the insertion of infraclavicular brachial plexus catheters.

Methods: Thirty patients scheduled to have upper limb surgery under regional block were studied. Under US guidance and peripheral nerve stimulation assistance, continuous peripheral nerve block needle and stimulating catheter were placed in the infraclavicular area. Needle and catheter tip location was confirmed with agitated 5% dextrose and seen under colour Doppler with US before injecting local anaesthetic (LA). Patients were evaluated in terms of onset times and efficacy of block. Post‐operatively, on block recession a catheter was stimulated and visualization of spread of LA during injection through the catheter was done. Secondary block (subsequent to re‐injection of LA) was assessed. Patients were followed‐up for a week.

Results: Mean time to onset of block was 19.7 (± 4.9) min. There were no incomplete blocks and all components of the plexus were blocked completely. Post‐operatively, in 95.7% of patients, the spread of hand‐agitated LA via the catheter could be seen by color Doppler with ultrasonography. All patients had excellent post‐operative analgesia and high degree of satisfaction. There were no complications.

Conclusion: Contrast enhancement with US guidance during infraclavicular brachial plexus block enables direct visualization of needle and catheter tip location. Our early experience suggests that this leads to successful initial and subsequent post‐operative block. Further controlled studies are needed to compare this technique with more prevalent and conventional techniques of catheter insertion.
Antinociceptive efficacy of levetiracetam in a mice model for painful diabetic neuropathy
Authors: OZCAN M. , AYAR A. , CANPOLAT S. , KUTLU S.
Published: August 2010

Background and Objective: Despite important advances in available knowledge, management of neuropathic pain remains incomplete, and results from experimental and clinical studies indicate that some anticonvulsants show promise for treating neuropathic pain. The aim of this study was to assess the antinociceptive efficacy of levetiracetam (LEV, ucb L059) in a mice model for painful diabetic neuropathy using the in vivo nociceptive behavioral ‘hot‐plate test.’

Methods: The hot‐plate test consisted of placing individual mice (adult male Balb/C) on the hot plate at 50±0.1 °C and timing the delay for the first hind paw lift (nociceptive threshold). After obtaining control values, diabetes was induced by injection of streptozotocin [200 mg/kg intraperitoneally (i.p.)] and 2 weeks after induction of diabetes (serum glucose ≥400 mg/dL) LEV was administered i.p. and hot‐plate tests were repeated. Pain threshold values were determined and analyzed by Kruskal–Wallis one‐way analysis of variance (ANOVA) followed by a pairwise comparison using a Dunnett's t‐test on the ranked data.

Results: LEV (60, 300 and 900 mg/kg) had no significant effect on the nociceptive threshold in normal mice (n=8 for each dose, P>0.05). There were significant decreases in pain threshold latency in diabetic mice compared with the normal healthy group and these were significantly and dose‐dependently restored by much lower doses of LEV (20, 100 and 200 mg/kg) in a reversible manner.

Conclusion: Results obtained from the in vivo behavioral test lend support to the validation of the promising therapeutic potential of the novel antiepileptic agent LEV in the treatment of neuropathic pain.
Pre‐operative carbohydrate loading may be used in type 2 diabetes patients
Authors: GUSTAFSSON U. O. , NYGREN J. , THORELL A. , SOOP M. , HELLSTRÖM P. M , LJUNGQVIST O. , HAGSTRÖM‐TOFT E.
Published: August 2010

Background: Post‐operative insulin resistance and hyperglycaemia are associated with an impaired outcome after surgery. Pre‐operative oral carbohydrate loading (CHO) reduces post‐operative insulin resistance with a reduced risk of hyperglycaemia during post‐operative nutrition. Insulin‐resistant diabetic patients have not been given CHO because the effects on pre‐operative glycaemia and gastric emptying are unknown.

Methods: Twenty‐five patients (45–73 years) with type 2 diabetes [glycated haemoglobin (HbA1c) 6.2 ± 0.2%, mean ± SEM] and 10 healthy control subjects (45–72 years) were studied. A carbohydrate‐rich drink (400 ml, 12.5%) was given with paracetamol 1.5 g for determination of gastric emptying.

Results: Peak glucose was higher in diabetic patients than in healthy subjects (13.4 ± 0.5 vs. 7.6 ± 0.5 mM; P<0.01) and occurred later after intake (60 vs. 30 min; P<0.01). Glucose concentrations were back to baseline at 180 vs. 120 min in diabetic patients and healthy subjects, respectively (P<0.01). At 120 min, 10.9 ± 0.7% and 13.3 ± 1.2% of paracetamol remained in the stomach in diabetic patients and healthy, subjects respectively. Gastric half‐emptying time (T50) occurred at 49.8 ± 2.2 min in diabetics and at 58.6 ± 3.7 min in healthy subjects (P<0.05). Neither peak glucose, glucose at 180 min, gastric T50, nor retention at 120 min differed between insulin (HbA1c 6.8 ± 0.7%)‐ and non‐insulin‐treated (HbA1c 5.6 ± 0.4%) patients.

Conclusions: Type 2 diabetic patients showed no signs of delayed gastric emptying, suggesting that a carbohydrate‐rich drink may be safely administrated 180 min before anaesthesia without risk of hyperglycaemia or aspiration pre‐operatively.
Does brain death induce a pro‐inflammatory response at the organ level in a porcine model?
Authors: BARKLIN A. , LARSSON A. , VESTERGAARD C. , KOEFOED‐NIELSEN J. , BACH A. , NYBOE R. , WOGENSEN L. , TØNNESEN E.
Published: August 2010

Background: Organs from brain‐dead donors have a poorer prognosis after transplantation than organs from living donors. A possible explanation for this is that brain death might initiate a systemic inflammatory response, elicited by a metabolic stress response or brain ischemia. The aim of this study was to investigate the effect of brain death on the cytokine content in the heart, liver, and kidney. In addition, the metabolic and hemodynamic response caused by brain death was carefully registered.

Methods: Fourteen pigs (35–40 kg) were randomized into two groups (1) eight brain‐dead pigs and (2) six pigs only sham operated. Brain death was induced by inflation of an epidurally placed balloon. Blood samples for insulin, glucose, catecholamine, free fatty acids (FAA), and glucagon were obtained during the experimental period of 360 min. At the conclusion of the experiment, biopsies were taken from the heart, liver, and kidney and were analyzed for cytokine mRNA and proteins [tumor necrosis factor α (TNF‐α), interleukin (IL)‐6, and IL‐10).

Results: We found a dramatic response to brain death on plasma levels of epinephrine (P=0.004), norepinephrine (P=0.02), FAA (P=0.0001), and glucagon (P=0.0003) compared with the sham group. There was no difference in cytokine content in any organ between the groups.

Conclusion: In this porcine model, brain death induced a severe metabolic response in peripheral blood. At the organ level, however, there was no difference in the cytokine response between the groups.
Operating room management: why, how and by whom?
Authors: MARJAMAA R. , VAKKURI A. , KIRVELÄ O.
Published: August 2010

Operating room (OR) is a cost‐intensive environment, and it should be managed efficiently. When improving efficiency, shortening case duration by parallel processing, training of the resident surgeons, the choice of anesthetic methods, effective scheduling, and monitoring of the overall OR performance are important. When redesigning the OR processes, changes should be given a clear target and the achieved results monitored and reported to everyone involved. Advanced, reliable, and easy to use information technology solutions for OR management are under development. Pre‐operative clinic and functionally designed facilities support efficiency. OR personnel must be kept motivated by clear management and leadership, supported by superiors.
Effects of fentanyl on gastric myoelectrical activity: a possible association with polymorphisms of the μ‐opioid receptor gene?
Authors: WALLDÉN J. , LINDBERG G. , SANDIN M. , THÖRN S.‐E. , WATTWIL M.
Published: August 2010

Background: Opioids have inhibitory effects on gastric motility, but the mechanism is far from clear. Electrical slow waves in the stomach determine the frequency and the peristaltic nature of gastric contractions. The primary aim of this study was to investigate the effects of the opioid fentanyl on gastric myoelectric activity. As there were large variations between the subjects, we investigated whether the variation was correlated to single nucleotide polymorphisms (SNP) of the μ‐opioid receptor (MOR) gene.

Methods: We used cutaneous multichannel electrogastrography (EGG) to study myoelectrical activity in 20 patients scheduled for elective surgery. Fasting EGG was recorded for 30 min, followed by intravenous administration of fentanyl 1 μg/kg and subsequent EGG recording for 30 min. Spectral analysis of the two recording periods was performed and the variables assessed were dominant frequency (DF) of the EGG and its power (DP). Genetic analysis of the SNP A118G and G691C of the MOR gene was performed with the polymerase chain reaction technique.

Results: There was a significant reduction in DF and DP after intravenous fentanyl. However, there was a large variation between the patients. In eight subjects EGG was unaffected, five subjects had a slower DF (bradygastria) and in six subjects the slow waves disappeared. We found no correlation between the EGG outcome and the presence of A118G or G691C in the MOR gene.

Conclusions: Fentanyl inhibited gastric myoelectrical activity in about half of the subjects. The variation could not be explained by SNP in the MOR gene. Because of small sample size, the results must be regarded as preliminary observations.
Renal cytokine profile in an endotoxemic porcine model
Authors: GRANFELDT A. , EBDRUP L. , TØNNESEN E. , WOGENSEN L.
Published: August 2010

Introduction:In animals exposed to acute endotoxemia with lipopolysaccharide (LPS), high levels of cytokines are found in the kidney. The objective of this study is to determine whether the high renal content of TNF‐α, IL‐1β, IL‐10 and IL‐1 receptor antagonist (IL‐1ra) is due to glomerular filtration and reabsorption, or whether the cytokines are produced locally in the kidney.

Methods:Eighteen anesthetized and mechanically ventilated pigs (35–43 kg) were randomized into two groups: Group 1 (n=12) LPS infusion for 360 min and Group 2 (n=6) control pigs, no treatment. At 360 min, the pigs were euthanized and tissue samples from the kidneys were obtained. Localization of the cytokines was determined by immunohistochemistry and double immunofluorescence (dIF).

Results:Pigs exposed to endotoxemia showed increased accumulation of leukocytes and increased protein expression of TNF‐α and IL‐1β when compared with controls. dIF showed that TNF‐α‐positive cells co‐localized with both endothelial and mesangial cells in the glomeruli. Furthermore, the endothelial cells of the cortical arterioles were positive for IL‐1β. TNF‐α and IL‐1β staining were absent in renal tubular cells. A positive signal for IL‐10 was detected at the tubular brush border while IL‐1ra was detected in the glomerulus and in the tubular cells.

Conclusion:LPS‐induced endotoxemia increased TNF‐α and IL‐1β protein expression and leukocyte accumulation in the kidneys. The results indicate that the increased levels of the pro‐inflammatory cytokines TNF‐α and IL‐1β are caused by a local production in the kidneys while the anti‐inflammatory cytokines IL‐10 and IL‐1ra are filtrated and reabsorbed in the tubuli.
Effect of oral gabapentin on the intraocular pressure and haemodynamic responses induced by tracheal intubation
Authors: Kaya F. N. , Yavascaoglu B. , Baykara M. , Altun G. T. , Gülhan N. , Ata F.
Published: August 2010

Background: Laryngoscopy and tracheal intubation may cause undesirable increases in blood pressure, heart rate (HR) and intraocular pressure (IOP). Gabapentin has been used effectively to attenuate the pressor response to laryngoscopy and tracheal intubation. We investigated whether the pre‐treatment with gabapentin attenuates the IOP in addition to a haemodynamic response to tracheal intubation.

Methods: Sixty ASA I–II patients were randomly allocated into two groups who received either gabapentin (800 mg) or placebo 2 h before surgery. IOP, mean arterial pressure (MAP) and HR were measured before and after the induction of anaesthesia as well as at 0, 1, 3, 5, 10 and 15 min following intubation.

Results: IOP and MAP increased from baseline immediately after intubation in the placebo group (P=0.001 and 0.002, respectively). When compared with the placebo group, IOP values of the gabapentin group were significantly lower for the first 15 min after tracheal intubation (P=0.002 at 0 min, P=0.006 at 1 min, P<0.001 at 3 min, P<0.001 at 5 min, P<0.001 at 10 min and P=0.003 at 15 min) while MAP was lower in the first 10 min (P=0.001 at 0 min, P=0.002 at 1 min, P<0.001 at 3 min, P<0.001 at 5 min and P=0.028 at 10 min). These results showed that gabapentin effectively suppresses the increase in IOP secondary to endotracheal intubation and attenuates the increases in MAP.

Conclusion: It is suggested that gabapentin is a useful adjuvant in order to prevent an increase in the IOP in response to laryngoscopy and tracheal intubation.
BIS does not predict dreams reported after anaesthesia
Authors: SAMUELSSON P. , BRUDIN L. , SANDIN R. H.
Published: August 2010

Background: In earlier studies, between 1% and 57% of patients have been reported to dream during anaesthesia. Thus, dreaming is much more common than definite memories of real events. We wanted to examine whether dreaming during anaesthesia is related to insufficient hypnotic action, as indicated by BIS levels and, thus, may constitute a risk for awareness.

Methods: After IRB approval, 2653 consecutive surgical patients were included. BIS registrations were recorded continuously during the anaesthetic procedure. The patients were interviewed on three occasions after anaesthesia. Standard questions, according to Brice, to evaluate awareness and dreaming during anaesthesia were asked. The dreams were categorized as either pleasant/neutral or unpleasant without any further evaluation of the dream content. Episodes with a mean BIS below 40, above 60 and above 70 were identified and subdivided according to duration (1, 2, 4 and 6 min, respectively). The total time as well as number and duration of episodes for the three BIS‐levels were used to analyze any relation to reported dreaming. The mean BIS was also analyzed.

Results: Dreaming during anaesthesia was reported by 211 of patients (8.0%) on at least one of the post‐operative interviews. BIS data did not show any significant correlation with dreaming, and neither did any of the tested case‐specific parameters (gender, age, ASA group, BMI, use of relaxants, induction agent, maintenance agent, length of procedure, omitting N2O and concomitant regional anaesthesia).

Conclusion: Dreaming during anaesthesia seems to be a separate phenomenon, not in general related to insufficient anaesthesia as indicated by high BIS levels.
Left molar approach improves laryngeal view in patients with simulated limitation of cervical movements
Authors: SAINI S. , BALA R. , SINGH R.
Published: August 2010

Background: Immobilized cervical spine, because of either diseases or stabilizing devices, poses considerable difficulties with endotracheal intubation due to poor laryngoscopic view. The left molar (LM) approach has been shown to be useful in difficult sporadic intubation cases. We evaluated efficacy of this approach of laryngoscopy to improve laryngeal view in patients with simulated limitation of cervical movements.

Methods: Thirty patients of American Society of Anesthesiologists grade I/II, who were scheduled to undergo routine surgical procedures under general anaesthesia and endotracheal intubation, were studied. A two‐piece semi‐rigid cervical collar was used to immobilize the cervical spine. Under standardized anaesthesia and neuromuscular blocking agent, conventional laryngoscopy using a curved Macintosh blade was performed and glottic view was recorded with and without optimal external laryngeal manipulation (OELM). Subsequently, in the same subjects the laryngoscope blade was withdrawn and re‐inserted through the LM approach and glottic view was recorded with and without OELM followed by tracheal intubation.

Results: With the conventional approach, laryngeal view was recorded as grade II in five patients, grade III in 24 patients, and grade IV in one patient. However, with the LM approach, laryngeal view was grade I in 25 patients, grade II in five patients, and grade III or IV in none (P<0.001). Tracheal intubation with the LM approach required the use of a flexible stylet to guide the tube tip into the larynx.

Conclusions: The laryngeal view is improved by the LM approach in patients with simulated limited cervical movements with a high success rate of tracheal intubation, but requires orientation for negotiation of the tube through the narrow oropharyngeal space available.
Diagnostic accuracy of bedside ultrasonography in the ICU: feasibility of detecting pulmonary effusion and lung contusion in patients on respiratory support after severe blunt thoracic trauma
Authors: ROCCO M. , CARBONE I. , MORELLI A. , BERTOLETTI L. , ROSSI S. , VITALE M. , MONTINI L. , PASSARIELLO R. , PIETROPAOLI P.
Published: August 2010

Background: Blunt thoracic trauma is a major concern in critically ill patients. Repeated lung diagnostic evaluations are needed in order to follow up the clinical situation and the results of the therapeutic strategies. The aim of this prospective clinical study was to evaluate the possible role of lung ultrasound (LU) compared with bedside radiography (CXR) and computed tomography (CT) used as the gold standard in the evaluation of trauma patients admitted to the intensive care unit with acute respiratory failure.

Method: A total of 15 thoracic trauma patients were studied at intensive care unit (ICU) arrival (T1) and 48 h later (T2) with CT, CXR and LU. We evaluated the presence of pleural effusion (PE) and lung contusion (LC). For this purpose the lung parenchyma was divided into 12 regions so that we could compare 180 lung regions at T1 and T2, respectively.

Results: Sensitivity of ultrasound was 0.94 for PE and 0.86 for LC while specificity 0.99 and 0.97, respectively. The likelihood ratio was 94 (ρ+) and 0.06 (ρ−) for PE and 28.6 (ρ+) and 0.14 (ρ−) for LC.

Conclusions: Ultrasound provides a reliable noninvasive, bedside method for the assessment of chest trauma patients with acute respiratory failure in the ICU.