British journal of anaesthesia
-
A 78-yr-old man, with halo frame cervical spine immobilization, suffered rapid respiratory deterioration after tracheal extubation in the intensive care unit. Control of the airway was difficult as bag-valve-mask ventilation was ineffective, tracheal intubation was known to be difficult from management of a previous episode of respiratory failure on the ward, and laryngeal mask insertion proved impossible. Rescue therapy using a Combitube airway is described and discussed.
-
Randomized Controlled Trial Clinical Trial
Effect of intravenous magnesium on pain and secondary hyperalgesia associated with the heat/capsaicin sensitization model in healthy volunteers.
We investigated the effects of i.v. magnesium on secondary hyperalgesia following heat/capsaicin stimulation in human volunteers. Twenty-five volunteers were included in this double blind, randomized, crossover study. ⋯ In contrast, painfulness of thermal stimulation was increased in normal skin. These results suggest that i.v. magnesium has no important analgesic effects in clinically relevant doses.
-
Comparative Study
Midazolam versus propofol for reducing contractility of fatigued canine diaphragm.
The effects of midazolam and propofol on the contractility of fatigued canine diaphragm were examined. Diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. After fatigue had been induced, group I (n=10) received no study drug, group II (n=10) was given a propofol infusion (0.1 mg kg(-1) loading dose plus 1.5 mg kg(-1) h(-1) maintenance dose) and group III (n=10) was given a midazolam infusion (0.1 mg kg(-1) loading dose plus 0.1 mg kg(-1) h(-1) maintenance dose). ⋯ Compared with group I, Pdi at 20 Hz stimulation was lower than fatigued values (P<0.05) during administration of the study drug in groups II and III. The decrease in Pdi was greater in group III than in group II (P<0.05). In conclusion, midazolam compared with propofol is associated with an inhibitory effect on contractility in the fatigued canine diaphragm.
-
Comparative Study
Downward movement of syringe pumps reduces syringe output.
We studied how lowering a syringe pump and changing the outflow pressure could affect syringe pump output. We experimentally reduced the height of three different syringe pump systems by 80 cm (adult setting) or 130 cm (neonatal setting), as can happen clinically, using five flow rates. We measured the time of backward flow, no flow and the total time without flow. ⋯ The compliance of the different syringe pumps and their infusion systems was linearly correlated with the effective time without infusion (r2=0.863, P<0.05). We conclude that the height of the syringe pumps should not be changed during transportation. If vertical movement of the syringe pump is necessary, the drugs should be diluted so that the flow rate is at least 5 ml h(-1).
-
Several risk scores have been developed to calculate the probability of postoperative nausea and vomiting (PONV). However, the power to discriminate which individual will suffer from PONV is still limited. Thus, we wondered how the number of predictors in a score affects the discriminating power and how the characteristics of a population--which is needed to measure the power of a score--may affect the results. ⋯ The currently available simplified risk scores (with four or five predictors) are useful both as a method to estimate individual risk of PONV and as a method for comparing groups of patients for antiemetic trials. They are also superior to single predictor models which are just using the patients' history of PONV or female gender alone. However, our analysis suggests that the power to discriminate which indvidual will suffer from PONV will remain imperfect, even when more predictors are considered.