Prospective single cohort study. To evaluate the NDI by comparison with the SF36 health Survey Questionnaire. The NDI is a simple ten-item questionnaire used to assess patients with neck pain. The SF36 measures functional ability, well being and the overall health of patients. It is used as a gold standard in health economics to assess the health utility, gain and economic impact of medical interventions. One hundred and sixty patients with neck pain attending the spinal clinic completed self-assessment questionnaires. A second questionnaire was completed in 34 patients after a period of 1-2 weeks. The internal consistency of the NDI and SF36 was calculated using Cronbach's alpha. The test-retest reliability was assessed using the Bland and Altman method. The concurrent validity of the NDI with respect to the SF-36 was assessed using Pearson correlations. Both questionnaires showed robust internal consistency: Cronbach's alpha for the NDI scale was acceptable (0.864, 95% confidence limits 0.825-0.894) though slightly smaller than that of the SF36. The correlations between each item of the NDI scores and the total NDI score ranged from 0.447 to 0.659, (all with P < 0.001). The test-retest reliability of the NDI was high (intra-class correlation 0.93, 95% confidence limits 0.86-0.97) and comparable with the best values found for SF36. The correlations between NDI and SF36 domains ranged from -0.45 to -0.74 (all with P < 0.001). We have shown that the NDI has good reliability and validity and that it compares well with the SF36 in the spinal surgery out patient setting.

We have studied, in 37 adult patients, the anatomy of the sacral extradural (caudal) space using magnetic resonance imaging. The sacrococcygeal membrane (SCM) could not be detected in 10.8% of patients. The maximum depth of the caudal space adjacent to the SCM was beneath the upper third of the SCM in more than 90% of patients (mean depth 4.6 mm; range 1.0-8.0 mm). The shortest linear distance from the dura to the upper limit of the SCM varied considerably (60.5 mm; 34-80 mm) as did the volume of the caudal space excluding the foraminae and dural sac (14.4 cm3; 9.5-26.6 cm3). The dimensions of the caudal space and their variability have implications for clinical practice and a knowledge of these dimensions may increase both the reliability and safety of caudal techniques in adult patients.

No abstract

We have evaluated the morphine-sparing effect of rectal paracetamol during the first 24 h after abdominal hysterectomy in a placebo-controlled, double-blind study. We studied 72 patients receiving patient-controlled analgesia (PCA) with i.v. morphine after a standardized anaesthetic, allocated randomly to receive rectal paracetamol 1.3 g, diclofenac 50 mg or placebo, after wound closure and at 8 and 16 h. Suppositories were blinded by the hospital pharmacy. Study violations excluded data from seven patients. Patient data, morphine doses during anaesthesia and recovery, and sedation and nausea scores were comparable. Mean morphine consumption during PCA was 35.0 (SD 20.4) mg, 32.7 (27.4) mg and 54.9 (28.3) mg in the paracetamol (n = 24), diclofenac (n = 20) and placebo (n = 21) groups, respectively (P < 0.05). Morphine sparing during PCA for paracetamol and diclofenac (36% vs 40% over 24 h) was significant from 4 h. Global scores of average pain over 24 h were lower after diclofenac compared with paracetamol (P < 0.01) and placebo (P = 0.08). We conclude that rectal paracetamol was an efficacious adjuvant analgesic after regular dosing.

Opioid analgesics have pharmacological effects in many organ systems, including the eye. Because the metabolites of morphine and codeine contribute to their overall pharmacological effect pupil diameter measurements were made over a 6-h period. We studied the pupillary effects of IV morphine (0.125 mg/kg), codeine (1 mg/kg), tramadol (1.25 mg/kg), or placebo (10 mL 0.9% w/v sodium chloride) in 10 healthy volunteers. Pupil diameter was measured every 30 min using a pupil densitometer. Comparisons of the change in pupil diameter for each drug were made using analysis of variance with repeated measures. No significant change in pupil diameter was observed after placebo. After IV morphine and codeine administration there was a 26% decrease in pupil diameter (P < 0.001). Over the course of the study period, pupil diameter gradually returned to baseline values. After administration of tramadol there were no significant changes in pupil diameter until 150 min after administration, after which there was a significant reduction for the remainder of the study period (P < 0.01). The changes in pupil diameter may be explained in part by the pharmacokinetic profiles of the opioids studied. Measurement of pupil diameter may have a place in monitoring the central effect of opioids.