Biomedical subjects

M Rockett

Publications and source records attributed to M Rockett.

4 recordsLinked to original sources

PubMed2000

Cricoid pressure: which hand?

We studied 20 anaesthetic assistants applying simulated cricoid pressure with the left or right hand in random order. Simulated cricoid pressure was continued for up to 5 min with one hand and then, after resting, with the other hand. Applied pressure was measured at intervals and the subjects were blind to the results. Nineteen assistants were right-handed and all routinely applied cricoid pressure with their right hand. Mean (SD) force applied during simulated 'awake' cricoid pressure was 13.8 (5.7) N with either left or right hand, and during 'anaesthetised' cricoid pressure it was initially 25.1 (8.2) N and 24.7 (8.8) N with left or right hand, respectively. Mean force was maintained above 20 N and below 30 N throughout the study period with either hand. Force applied with the left hand was significantly lower than with the right hand but the difference was clinically insignificant (0.4 N). Inadequate or excessive force was more frequently associated with use of the left hand (p < 0.0001). Cricoid pressure was released before 5 min in three cases, two left-handed and one right-handed. Our results demonstrate that anaesthetic assistants apply a lower force than is classically taught and are able to maintain the force with either hand for a sustained period. Application with the left hand is justified where clinically indicated but may have a lower margin for error than when applied with the right hand.

Anesthesia, General↗

PubMed1998

Ankle fracture classification: a comparison of reliability of three X-ray views versus two.

Our hypothesis was that malleolar ankle fractures could be classified with two radiographic views as reliably as with three views. Four different observers independently evaluated 99 sets of ankle radiographs. The examiners classified the ankle fractures by using both the Lauge-Hansen and Danis-Weber systems. The interobserver and intraobserver variations were analyzed by kappa statistics. With regard to intraexaminer reliability, the examiners demonstrated excellent accord in classifying the fractures in the Danis-Weber system with either three views or two views. The kappa values were comparable. In the Lauge-Hansen system, three examiners demonstrated excellent accord and one examiner demonstrated good accord in classifying the fractures. Similar kappa values were generated when examiners classified fractures with either three views or two views. With regard to interexaminer reliability, good to excellent accord was demonstrated overall among the four examiners when they used the Danis-Weber system with either three views or two views. The examiners were in good agreement when they used the Lauge-Hansen system. Similar kappa values were generated whether the examiners used three views or two views. Three radiographic views are usually ordered for evaluation of an acute ankle injury. Previous studies have shown that only two views are needed for diagnosis of a malleolar ankle fracture. This study demonstrates that malleolar ankle fractures can be classified with two views, lateral or mortise, with a reliability as good as that achieved with three views. The best agreement is achieved with lateral and mortise views.

Ankle Injuries↗

PubMed1998

Ultrasonographic-surgical correlation of ankle tendon tears.

This study evaluates the accuracy of ultrasonography in detecting ankle tendon tears of the peroneal, posterior tibial, and flexor digitorum longus tendons based on operative findings and clinical follow-up. A prospective study was performed in 33 patients with clinically suspected tendon injury. Sixty-eight tendons were evaluated sonographically. The diagnosis of an intrasubstance tear was made when disruption of uniform tendon architecture by hypoechoic linear or globular clefts was observed. Criteria used to diagnose complete tendon rupture included discontinuity or gap within the tendon or complete nonvisualization of the tendon. Treatment decisions were based on a combination of clinical parameters and imaging studies. Twenty-six patients had the presence or absence of tear confirmed at surgery. Five patients had a final diagnosis based on clinical findings, and two were lost to follow-up. Of the 68 tendons evaluated sonographically, 54 were directly inspected at surgery; 20 were found to be torn and 34 were intact. Ultrasonography was able to identify all tears correctly with an accuracy of 93%, a sensitivity of 100%, and a specificity of 88%. The positive and negative predictive values were 83% and 100%, respectively. The combined accuracy, sensitivity, and specificity of ultrasonography in detecting tendon tears in all patients evaluated both surgically and by clinical follow-up were 94%, 100%, and 90%, respectively.

Adult↗

PubMed1987

Blue-yellow vision deficits in patients with diabetes.

Home blood glucose monitoring has been introduced as a means to achieve good control in patients with diabetes mellitus. Many patients use color-reagent strips and color comparisons to determine blood glucose levels. Intact color vision in the blue-yellow range is necessary for accurately interpreting these strips.Blue-yellow vision deficits occur as a consequence of eye disease and are not genetic or sex-linked. We evaluated blue-yellow vision acuity in 70 diabetic patients and in 19 age-matched control subjects. The patients with diabetes were subdivided according to their degree of retinopathy as follows: no disease (N = 14), nonproliferative diabetic retinopathy (N = 16), proliferative diabetic retinopathy (N = 14) and postlaser-treated (N = 26). None of the control group had deficits. Each group of diabetic patients had a statistically significant increase in color vision deficits compared with the controls. In the laser-treated group, deficits occurred in most patients, were more severe and were significantly increased over all other diabetic subgroups. These deficits may impair visual interpretation of home blood glucose monitoring strips.

Aged↗