Transmitral inflow patterns have been used for detection of myocardial ischaemia. However, its diagnostic value has not been tested in anaesthetized and mechanically ventilated patients undergoing coronary artery bypass graft surgery.

Transmitral inflow patterns were studied by transoesophageal Doppler echocardiography in 43 patients undergoing coronary artery bypass graft surgery without cardiopulmonary bypass after opening of the sternum (baseline) and during grafting of the left anterior descending artery. Peak early (E) and peak late (A) transmitral velocities and their ratio (E/A) were recorded. Myocardial ischaemia was defined by standard criteria using two-dimensional echocardiography and seven-lead electrocardiogram.

Thirty-one patients (64 ± 8 yr, 9 women) fulfilled the predefined inclusion criteria for analysis. During distal revascularization, 16 patients showed myocardial ischaemia and 15 did not. The use of vasoactive drugs, haemodynamic findings and transmitral inflow patterns were similar in both groups at baseline and during grafting. In the ischaemic group, E was 67.1 ± 13.9 cm s−1 at baseline and 69.5 ± 23.2 cm s−1 during grafting, and the E/A ratios were 1.3 ± 0.3 and 1.4 ± 0.9, respectively. In the non-ischaemic group, E was 64.0 ± 17.1 cm s−1 at baseline and 60.9 ± 14.8 cm s−1 during grafting, and the E/A ratios were 1.4 ± 0.7 and 1.2 ± 0.3, respectively.

Analysis of Doppler findings of transmitral inflow patterns did not allow for detection of myocardial ischaemia during surgical revascularization of the myocardium.

Levosimendan has a cardioprotective action by inducing coronary vasodilatation and preconditioning by opening KATP channels. The aim of this study was to determine whether levosimendan enhances myocardial damage during hypothermic ischaemia and reperfusion in isolated rat hearts.

Twenty-one male Wistar rats were divided into three groups. After surgical preparation, coronary circulation was started by retrograde aortic perfusion using Krebs–Henseleit buffer solution and lasted 15 min. After perfusion Group 1 (control; n = 7) received no further treatment. In Group 2 (non-treated; n = 7), hearts were arrested with cold cardioplegic solution after perfusion and subjected to 60 min of hypothermic global ischaemia followed by 30 min reperfusion. In Group 3 (levosimendan treated; n = 7), levosimendan was added to the buffer solution during perfusion and the hearts were arrested with cold cardioplegic solution and subjected to 60 min of hypothermic global ischaemia followed by 30 min reperfusion. At the end of the reperfusion period, the hearts were prepared for biochemical assays and for histological analysis.

Tissue malondialdehyde levels were significantly lower in the levosimendan-treated group than in the non-treated group (P = 0.019). The tissue Na+–K+ ATPase activity was significantly decreased in the non-treated group than in the levosimendan-treated group (P = 0.027). Tissue myeloperoxidase (MPO) enzyme activity was significantly higher in the non-treated group than in the levosimendan-treated group (P = 0.004). Electron microscopic examination of the hearts showed cardiomyocytic degeneration at the myofibril, mitochondria and sarcoplasmic reticulum in both non-treated and levosimendan-treated groups. The severity of these findings was more extensive in the non-treated group.

Treatment with levosimendan provided better cardioprotection with cold cardioplegic arrest followed by global hypothermic ischaemia in isolated rat hearts.

Thoracic surgery requires immobilization of the operating area. Usually, this is achieved with one-lung ventilation (OLV), however this may still lead to some movement. High-frequency jet ventilation (HFJV) may be an alternative way of ventilation in thoracic surgery. The purpose of this study was to determine the effectiveness of HFJV as an alternative option to OLV for thoracic procedures.

Sixty patients were randomized to receive either HFJV (n = 29) or OLV (n = 31) during the operation. During the course of the study 10 patients were excluded (4 patients in HFJV group and 6 patients in OLV group). The following haemodynamic and ventilatory parameters were recorded: heart rate, systolic and mean blood pressure, ventricular stroke volume, cardiac index, systemic vascular resistance, peak inspiratory pressure, oxygen saturation, PaO2 and PaCO2. Overall parameters were documented before the initiation of the chosen mode of ventilation every 15 min during the operation.

Patients in both groups showed comparable cardiovascular function. Mean values of peak inspiratory pressure were significantly higher in the OLV group. Oxygen saturation values were statistically higher in the HFJV group. PaCO2 values were similar in both during surgery, but were higher in the OLV group after awakening. Mean values of shunt fraction were lower in the HFJV group. Lower values of peak inspiratory pressure were therefore associated with higher partial pressure of carbon dioxide levels in the HFJV group. In the OLV group, 44% of patients experienced a postoperative sore throat. Operating conditions were comparable.

HFJV is safe option, comparable to OLV and offers some advantages for open-chest thoracic procedures.

Functional endoscopic sinus surgery can be performed under either local or general anaesthesia. The objective of this study was to investigate the haemodynamic effects of perioperatively administered dexmedetomidine, a new generation α-2-agonist, in patients for functional endoscopic sinus surgery.

Sixty-two patients who were planned to undergo functional endoscopic sinus surgery under local anaesthesia were included in the study. Following meperidine premedication, both groups were monitored in a standard manner with electrocardiogram, non-invasive blood pressure and percentages of peripheral saturation of oxygen. Saline intravenous infusion was started in the placebo group, and dexmedetomidine bolus intravenous infusion (an initial loading dose of 1 μg kg−1 given for a 10-min period followed by 0.7 μg kg−1 h−1) was administered to the treatment group. Maintenance dose infusion was stopped 15 min before the end of the surgical procedure.

Systolic, diastolic and mean arterial pressures, and heart rate markedly decreased in the dexmedetomidine group. However, dexmedetomidine had no effect on serum nitric oxide levels, measured by a nitric oxide/ozone chemiluminescence method. No significant difference was found in oxygen saturation levels of the two groups. Postoperative nausea and vomiting rates were significantly lower in the dexmedetomidine group. No adverse effects were observed with this α-2-agonist. Dexmedetomidine provided appropriate levels of sedation.

These results suggest that dexmedetomidine provides analgesia, adequate sedation and surgical comfort without adverse effects for patients undergoing functional endoscopic sinus surgery under local anaesthesia.

In emergency trauma situations, manual in-line stabilization of the cervical spine is recommended to reduce cervical spine movement during intubation. The aim of this study was to compare the effect of manual in-line stabilization during different intubation techniques on three-dimensional cervical spine movements and times to intubation.

Forty-eight subjects without any history of trauma, inflammatory or degenerative disorder of the cervical spine were randomly grouped, regardless of gender or age. All underwent elective surgery under general anaesthesia. Under manual in-line stabilization, laryngeal intubation with Macintosh laryngoscope, intubating laryngeal mask airway, fibre-endoscopic oral intubation and fibre-endoscopic nasal intubation was performed. During the intubation process, cervical three-dimensional motion was detected by an ultrasound real-time motion analysis system and intubation times were measured.

Cervical spine range in the extension/flexion direction of orolaryngeal intubation with Macintosh (17.57 ± 8.23°) showed significantly more movement than using the intubating laryngeal mask airway (4.60 ± 1.51°) and fibreoptic procedures. Intubating laryngeal mask airway was significantly different than the fibreoptic intubation techniques. There was also a significant difference between oral (3.61 ± 2.25°) nasal and (5.88 ± 3.11°) fibreoptic intubation. Times to intubation all differed significantly (P < 0.05) for the Macintosh laryngoscope (27.25 ± 8.56 s) and for the intubating laryngeal mask airway (16.5 ± 9.76 s). Fibreendoscopic laryngoscopic oral (52.91 ± 56.27 s) and nasal (82.32 ± 54.06 s) intubation resulted in further prolongation of the times to intubation.

The intubating laryngeal mask airway with manual in-line stabilization is a potentially useful adjunct to intubation of patients with potential cervical spine injury, if there are no contraindications to these methods. These results predict that fibreoptic procedures may be a safe instrument for airway management in patients with potential cervical spine injuries; however, the main disadvantages are the longer intubation times.

A significant proportion of preschool children experiences severe emergence agitation after anaesthesia. The symptoms of disorientation, restlessness, inconsolable crying and thrashing resemble an acute psychosis similar to an agitated central anticholinergic syndrome. The primary aim of this randomized controlled study was to assess the efficiency of the cholinesterase-inhibitor physostigmine in these children and to identify adverse effects.

We anaesthetized 211 children (1–5 yr) with sevoflurane after midazolam premedication for varying operative procedures. Multimodal intraoperative and prophylactic pain therapy combined alfentanil, piritramide, diclofenac and regional/local bupivacaine. A 5-step score assessed emergence agitation. Severely agitated children were treated immediately with physostigmine (30 μg kg−1) or placebo in a randomized, double-blind fashion. The primary variable was the agitation score after 5 min.

Severe delirium occurred in 19% of all children. Five minutes following injection, severe agitation was still present in 10 out of 20 patients treated with physostigmine and 16/20 with placebo. This difference did not reach statistical significance (P = 0.1). Rescue therapy with intravenous propofol was given after 15 min of severe agitation to four children following physostigmine and nine following placebo (non-significant). An increased rate of postoperative nausea and vomiting (45% vs. 15%, P < 0.05) was the only adverse effect observed.

Severe emergence agitation might be related to a central anticholinergic syndrome as diagnosed empirically with a successful treatment with physostigmine. However, the results of this study do not support its routine use. The substance may augment the therapeutic options if injected slowly and after suitable prophylaxis to avoid postoperative nausea and vomiting.

The Bullard laryngoscope can be useful in management of difficult airway. When the endotracheal tube is advanced over the original Bullard laryngoscope stylet, the endotracheal tube sometimes makes contact with structures around the vocal cords, especially the right arytenoids. A similar problem also occurs with flexible fibreoptic intubation and it has been shown that use of the Parker Flex-Tip™ tube usually resolves the problem. In this study we tested our hypothesis that use of the Parker Flex-Tip™ tube might improve endotracheal tube passage with the Bullard laryngoscope.

Forty patients scheduled for elective anaesthesia were randomly assigned into group ST (standard tube) or Group PT (Parker Flex-Tip™ tube). The time taken to achieve successful endotracheal tube placement after obtaining the best laryngeal view, the number of attempts at intubation and the incidences of successful intubation at first attempt and of re-direction of the Bullard laryngoscope during intubation were recorded. Unpaired t-test and χ2-test were employed and P < 0.05 was considered significant.

Use of the Parker Flex-Tip™ tube reduced the time required for successful endotracheal tube placement after the best laryngeal view was obtained from 14 ± 6 to 6 ± 2 s (P < 0.01). It also reduced the incidence of requirement for re-direction of the Bullard laryngoscope during intubation from 10/19 to 1/19 (P < 0.01). The incidence of successful intubation at the first attempt (18/19 vs. 15/19) was higher in the PT group but the difference was not statistically significant.

During intubation with the Bullard laryngoscope, use of the Parker Flex-Tip™ tube is associated with more rapid success and a lower incidence of re-direction of the Bullard laryngoscope during endotracheal intubation when compared to a standard endotracheal tube.

The caffeine/halothane contracture test in North America and the in vitro contracture test in Europe are currently the only validated bioassays for diagnosing malignant hyperthermia susceptibility and phenotyping families. Both tests are invasive requiring surgical muscle biopsy. Here, we report first use of the selective ryanodine receptor type I agonist ryanodine in a percutaneous microdialysis protocol designed to test whether microdialysis-induced local metabolic responses of skeletal muscle due to ryanodine receptor activation can differentiate between malignant hyperthermia-sensitive and normal pigs.

Six microdialysis catheters were implanted percutaneously into the adductor muscles of the right and left thighs of malignant hyperthermia-susceptible (n = 9) and normal (n = 8) anaesthetized (ketamine/propofol) and mechanically ventilated swine. Systemic blood gases, haemodynamic parameters and creatine kinase levels were measured before, during and after microdialysis perfusion of ryanodine. After a post-implantation equilibration period of 30 min, one catheter perfused (2 μL min−1) with 0.9% NaCl (control) and was compared with the remaining five catheters perfused with increasing concentrations of ryanodine (0.2–100 μmol). Lactate and pyruvate levels were measured enzymatically.

Continuous perfusion with ryanodine revealed dose-dependent sigmoidal increases in the dialysate lactate and lactate–pyruvate ratio parameters; these effects were greatly augmented in malignant hyperthermia-susceptible pigs compared to normal pigs (two- to threefold): estimated EC50 greatly decreased (>19-fold) while the maximum effect increased (>twofold) in the malignant hyperthermia-susceptible group.

The in vivo percutaneous microdialysis protocol for skeletal muscle, using ryanodine as the ryanodine receptor type I agonist and dialysed lactate–pyruvate parameters as metabolic index, can reproducibly differentiate between malignant hyperthermia-susceptible and normal swine.

To evaluate the current clinical attitude in enteral nutrition support and motility disorders in adult critically ill patients on German intensive care units.

A total of 1493 questionnaires, including 25 items on the medical environment, treatment of motility disorders and enteral nutrition, were sent to German intensive care units in September 2005. Responses were collected during a 2-month period.

A total of 593 questionnaires were returned (response rate 41%). The intensive care units were mainly led by anaesthesiologists (63%) or internists (17%). Standard nutrition protocols were used in 44%. Feeding was mainly started as a combined enteral–parenteral regimen (70%). Early enteral nutrition was performed in 58% using a volume of 250–500 mL (66%) and increased by 200–400 mL day−1 (55%). It was mainly delivered by gastric tube (76%) via continuous pump systems (72%) with short interruption intervals of <4 h (86%). Enteral nutrition solutions were mainly standard polymeric formulae (86%). Modified solutions for diabetics and those with renal or liver failure were uncommonly used; immunonutrition did not play a role. Prokinetic agents, especially metoclopramide, laxatives and neostigmine, were routinely used (39%). Further therapeutic options in motility dysfunction included purgative enemas (96%), gastrografin (72%) and colon massage (39%).

The concept of early enteral nutrition has been well established and approved in German intensive care units, though the recommendations only meet level C criteria in the current ESPEN guidelines. The current survey may serve for further updates on practical nutrition support in intensive care medicine.

The alpha-2 adrenergic agonists clonidine and dexmedetomidine are used as an antihypertensive and a sedative, respectively. The aim of this study was to determine the effects of these agonists on ovalbumin-sensitized airway tone in guinea pigs.

The animals were divided into two groups: control and sensitized. The sensitized group received ovalbumin intraperitoneally and was boosted by exposure to aerosolized ovalbumin. The effects of the alpha-2 agonists were investigated by measuring (1) total lung resistance and (2) smooth muscle tension using a tracheal ring preparation.

In the control group, acetylcholine significantly increased total lung resistance in a dose-dependent manner. In the sensitized animals, total lung resistance was significantly higher (by 95%) at 6 μg kg−1 acetylcholine than that in the control group. Both clonidine and dexmedetomidine had a slight but significant inhibitory effect on the response curve of lung resistance at higher concentrations of carbachol, a potent muscarinic receptor agonist. Similar to the data obtained in the control group, both clonidine and dexmedetomidine significantly decreased total lung resistance and the inhibitory effects of these alpha-2 agonists on lung resistance were significantly distinguishable. Similar direct inhibitory effects of the alpha-2 agonists on carbachol-induced muscle contraction were observed in both the control and sensitized groups, the inhibitory effects in the sensitized group being significantly greater.

Both clonidine and dexmedetomidine can relax the airway even in the hyper-reactive state.