Extracellular cyclophilin A may be a potential target to protect against myocardial reperfusion injury

Myocardial reperfusion injury is increasingly recognized as an inflammatory process, characterized by neutrophil recruitment and subsequently excessive release of pro-inflammatory factors. Recently, the extracellular cyclophilin A (CypA) has been showed to play an important role in initiation and development of inflammation by chemo trafficking of leukocytes into inflamed tissues, eliciting massive release of pro-inflammatory cytokines, and inducing production of matrix metalloproteinases. Also, the agents targeting CypA have been demonstrated to promise anti-inflammatory effects in the different experimental models of inflammatory diseases including acute lung injury, rheumatoid arthritis, and atherosclerosis. Therefore, we hypothesize that the extracellular CypA may in some way implicated in the pathogenesis of reperfusion-induced inflammatory process, and the specific inhibitors of the extracellular CypA can provide a protection against the myocardial reperfusion injury.

The effects of head flexion on airway seal, quality of ventilation and orogastric tube placement using the ProSeal laryngeal mask airway

This prospective self-controlled study was designed to evaluate the influences of head flexion on airway seal, quality of ventilation, and orogastric tube placement through the ProSeal laryngeal mask airway (ProSeal LMA) in 80 anaesthetised, paralysed adult patients. After the ProSeal LMA was inserted and the cuff pressure was set at 5.9 kPa, ventilation quality, airway seal pressure, fibreoptic positions of the cuff and the drainage tube, orogastric tube placement and efficacy of intermittent positive pressure ventilation (IPPV) were assessed in two randomly selected positions: neutral and flexed position. When compared to the neutral head position, the head flexed significantly improved the airway seal pressure and the quality of ventilation of the ProSeal LMA (p < 0.05). Fibreoptic scores of the cuff position did not correlate with either the ability to obtain excellent or adequate ventilation through the ProSeal LMA or the ability to generate an airway seal pressure of >or= 2 kPa. Orogastric tube placement via the drainage tube was successful on the first attempt in all patients in the neutral position compared with seven failures following three attempts in the flexed position (p < 0.05). There were no significant differences between the two head positions in the volume of air required to obtain an intracuff pressure of 5.9 kPa, fibreoptic score of the drainage tube position, and expiratory tidal volume and peak inspiratory pressure during IPPV (p > 0.05). In conclusion, head flexion improves airway seal and ventilation quality of the ProSeal LMA. However, placement of an orogastric tube via the drainage tube is impaired in the flexed position compared to the neutral position. Fibreoptic scoring of the ProSeal cuff position is not an accurate test to assess the airway seal and ventilation function.

Different small-dose sufentanil blunting cardiovascular responses to laryngoscopy and intubation in children: a randomized, double-blind comparison

BACKGROUND

Sufentanil is a potent opioid analgesic frequently used in clinical anaesthesia. This prospective, randomized, double-blind study was designed to assess the efficacy of different small-dose sufentanil attenuating the cardiovascular intubation response in healthy children, aiming at determining the optimal dose of sufentanil for this purpose.

METHODS

A total of 165 children aged 3-9 yr were randomized to one of four groups to receive the following in a double-blind manner: normal saline (Group 1), sufentanil 0.1 microg kg(-1) (Group 2), sufentanil 0.2 microg kg(-1) (Group 3), and sufentanil 0.3 microg kg(-1) (Group 4). Anaesthesia was induced with propofol 2.5 mg kg(-1) and vecuronium 0.1 mg kg(-1). Non-invasive blood pressure (BP) and heart rate (HR) were recorded before induction of anaesthesia (baseline value), at immediately before intubation (post-induction values), at intubation, and at 1 min intervals for 5 min after intubation. The per cent changes of systolic blood pressure (SBP) and HR during the observation were calculated.

RESULTS

Except for Group 4, tracheal intubation caused significant increases in BP and HR in Groups 1, 2, and 3 compared with baseline values. BP and HR at intubation and their maximum values during the observation were significantly different among the four groups. The maximum per cent increases of SBP and HR during the observation were 20 and 28% of baseline values, respectively, in Group 2, 13 and 13% in Group 3, and 0 and 4% in Group 4 compared with 24 and 37% in Group 1. Except for the Group 3 vs Group 4 comparison, the incidences of SBP and HR per cent increases >30% of baseline values were also significantly different among the four groups.

CONCLUSIONS

In combination with propofol for induction of anaesthesia in children, the bolus administration of sufentanil can produce a dose-related attenuation of the cardiovascular intubation response and sufentanil 0.3 microg kg(-1) can completely abolish the cardiovascular intubation response.