Anaesthesia and intensive care
-
Anaesth Intensive Care · Apr 2004
Comparative StudyThe type of carbon dioxide absorbent has no relation to the concentration of carbon monoxide in the breathing circuit during low-flow isoflurane anaesthesia in smoking and non-smoking subjects.
The present study was designed to investigate the concentrations of carbon monoxide (CO) in the anaesthetic circuit and of arterial carboxyhaemoglobin (COHb) during low-flow isoflurane anaesthesia in smoking and non-smoking subjects using three kinds of cardon dioxide (CO2) absorbent. Thirty smoking and 30 non-smoking subjects were selected for this study, and these two groups were each divided into three groups according to the type of CO2 absorbent used (Wakolime A, Drägersorb Free, and Amsorb). Anaesthesia was maintained with 1.0% isoflurane and nitrous oxide (1. 0 l min(-1))/oxygen (1.0 l min(-1)). ⋯ There was a significant linear correlation between the concentrations of CO and COHb (r=0.86, n =30, P<0.001). In the non-smoking groups all of the parameters remained constant at low levels that were independent of the type of CO2 absorbents tested. The major source for increased intraoperative CO exposure is related to the patient's smoking status, and the type of CO2 absorbent used has no relation to an increase in CO concentration in the breathing circuit.
-
Anaesth Intensive Care · Apr 2004
Muscle weakness after muscle relaxants: an audit of clinical practice.
Residual muscle weakness after general anaesthesia, assessed using handgrip strength, was audited in a teaching hospital. The relationships between residual weakness, the use of muscle relaxants and patient characteristics were examined. Handgrip strength was measured preoperatively, one hour postoperatively and one day postoperatively using a hand dynamometer in 151 patients having general anaesthesia. ⋯ The mean decline in handgrip strength in the male patients who received either vecuronium or rocuronium was similar to that seen when relaxants had not been used (P=0.40). One hour postoperatively, female patients showed a marked decrease in handgrip strength after both vecuronium and rocuronium (32% and 34% respectively, combined P=0.01). These results suggest that in usual clinical practice at our institution, female patients are more likely to have residual weakness after muscle relaxants.
-
Anaesth Intensive Care · Apr 2004
The effect of haemodilution on antithrombin concentration during cardiac surgery.
The effect of haemodilution on antithrombin concentration was investigated in 73 patients undergoing elective cardiac surgery with and without cardiopulmonary bypass. In patients who required cardiopulmonary bypass (n = 45), the antithrombin concentration fell to 52% of baseline during surgery (24.2 mg.dl(-1) to 12.6 mg.dl(-1)), and the haemoglobin level fell to 55% (136 g.l(-1) to 75 g.l(-1)). ⋯ The results indicate that most of the decrease in concentration of antithrombin during cardiac surgery is a consequence of cardiopulmonary bypass and is due to haemodilution. This data demonstrates that the percentage decrease in haemoglobin concentration can be used to estimate the percentage decrease in antithrombin concentration that occurs during cardiac surgery, if blood products that might effect the results are not administered between measurements.
-
Anaesth Intensive Care · Apr 2004
Review Case ReportsFatal systemic air embolism during endoscopic retrograde cholangio-pancreatography.
Air embolism is a rare complication of gastrointestinal endoscopy. We present a 56-year-old male who developed both venous and systemic arterial air embolism during an endoscopic retrograde cholangiopancreatogram. ⋯ Clinical diagnosis of air embolism during endoscopy is difficult and urgent echocardiography is the investigation of choice. Treatment is largely supportive but hyperbaric oxygen therapy should be considered in any severe cases, especially if neurological injury is present.
-
Anaesth Intensive Care · Apr 2004
Randomized Controlled Trial Clinical TrialOral ketamine or midazolam or low dose combination for premedication in children.
This randomized controlled trial was designed to evaluate whether the combination of low dose oral midazolam (0.25 mg/kg) and low dose oral ketamine (3 mg/kg) provides better premedication than oral midazolam (0.5 mg/kg) or oral ketamine (6 mg/kg). Seventy-eight children of ASA physical status I or II scheduled for elective ophthalmic surgery were randomly divided into three groups and given premedication in the holding area 30 minutes before surgery. Two subjects from each group vomited the medication and were excluded, leaving 72 subjects for further analysis. ⋯ Recovery was earlier in the combination group, as the time required to reach a modified Aldrete score of 10 was significantly less in the combination group (22+/-5 min) than in the oral midazolam (36+/-11 min) or ketamine (38+/-8 min) groups. The incidence of excessive salivation was significantly higher in the ketamine alone group (P<0.05). In conclusion, the combination of oral ketamine (3 mg/kg) and midazolam (0.25 mg/kg) has minimal side effects and gives a faster onset and more rapid recovery than ketamine 6 mg/kg or midazolam 0.5 mg/kg for premedication in children.