Intrathecal morphine in combination with bupivacaine as pre-emptive analgesia in posterior lumbar fusion surgery: a retrospective cohort study

Background

The purpose of this study was to evaluate the efficacy of intrathecal morphine (ITM) in combination with bupivacaine as pre-emptive analgesia in patients undergoing posterior lumbar fusion surgery. This is in comparison with traditional opioid analgesics such as intravenous (IV) morphine.

Methods

Two groups were identified retrospectively. The first (ITM group) included patients who had general anaesthesia (GA) with low-dose spinal anaesthesia prior to induction using 1–4 mls of 0.25% bupivacaine and 0.2 mg ITM. 1 ml of 0.25% bupivacaine was administered per hour of predicted surgery time, up to a maximum of 4 ml. The insertion level for the spinal anaesthetic corresponded to the spinal level of the iliac crest line and the level at which the spinal cord terminated. The control group had GA without any spinal anaesthesia. Patients were instead administered opioid analgesia in the form of IV morphine or diamorphine. The primary outcome was the consumption of opioids administered intraoperatively and in recovery, and over the first 48 h following discharge from the post-anaesthesia care unit (PACU). Total opioid dose was measured, and a morphine equivalent dose was calculated. Secondary outcomes included visual analogue scale (VAS) pain scores in recovery and at day two postoperatively, and the length of stay in hospital.

Results

For the ITM group, the median total amount of IV morphine equivalent administered intraoperatively and in recovery, was 0 mg versus 17 mg. The median total amount morphine equivalent, administered over the first 48 h following discharge from PACU was 20 mg versus 80 mg. Both are in comparison with the control group. The median length of stay was over 1 day less and the median VAS for pain in recovery was 6 points lower. No evidence was found for a difference in the worst VAS for pain at day two postoperatively.

Conclusion

ITM in combination with bupivacaine results in a significantly decreased use of perioperative opioids. In addition, length of hospital stay is reduced and so too is patient perceived pain intensity.

Trial registration The study was approved by the ethics committee at The Robert Jones and Agnes Hunt Orthopaedic Hospital as a service improvement project (Approval no. 1617_004).

Characterization of soft tissue tumours with ultrasound, shear wave elastography and MRI

OBJECTIVE

To predict accurately whether a soft tissue mass was benign or malignant and to characterize its type using ultrasound, shear wave elastography and MRI. We hypothesized that with the addition of shear wave elastography, it would be possible to determine a threshold velocity value to classify a lesion as benign or malignant.

MATERIALS AND METHODS

A total of 151 consecutive, consenting adult patients were prospectively recruited to this study in a tertiary referral musculoskeletal oncology centre. All lesions were assessed with ultrasound, including B mode, Doppler and shear wave elastography measurements. One hundred thirty-eight patients also underwent MRI of the lesion. A histological diagnosis was obtained for all lesions.

RESULTS

Malignant lesions were larger than benign lesions and had a greater Doppler activity. There was no useful threshold shear wave velocity to differentiate between benign and malignant lesions. Longitudinal and transverse shear wave velocities were strongly positively correlated with each other. An inverse correlation was shown with lesion size and depth, regardless of whether it was benign or malignant. A logistic regression model combining the ultrasound and MRI characteristics did not confidently classify a lesion as benign or malignant and was inferior to expert opinion.

CONCLUSION

The strongest predictors of malignancy are large lesion size and high vascularity. The combination of all ultrasound characteristics (including shear wave elastography) and MRI features does not confidently classify a lesion as benign or malignant, and histological diagnosis remains the gold standard.

The use of plots in orthopaedic literature

Plots are an elegant and effective way to represent data. At their best they encourage the reader and promote comprehension. A graphical representation can give a far more intuitive feel to the pattern of results in the study than a list of numerical data, or the result of a statistical calculation. The temptation to exaggerate differences or relationships between variables by using broken axes, overlaid axes, or inconsistent scaling between plots should be avoided. A plot should be self-explanatory and not complicated. It should make good use of the available space. The axes should be scaled appropriately and labelled with an appropriate dimension. Plots are recognised statistical methods of presenting data and usually require specialised statistical software to create them. The statistical analysis and methods to generate the plots are as important as the methodology of the study itself. The software, including dates and version numbers, as well as statistical tests should be appropriately referenced. Following some of the guidance provided in this article will enhance a manuscript.

The outcome of patients sustaining a proximal femur fracture who suffer from alcohol dependency

There are many negative health consequences associated with alcohol dependency. Fractures of the proximal femur carry significant morbidity and mortality. This study examines the outcomes in patients with alcohol dependency, who sustain a fracture of the proximal femur. Twenty-eight consecutive alcohol dependent patients who suffered a fracture of the proximal femur were identified over a three year period. Data were collected on demographics, co-morbidity, surgical factors, mobility and mortality. The median age of patients was 61 years. The median weekly alcohol intake was 158 units. Thirteen patients sustained an extra-capsular fracture and 15 an intra-capsular proximal femoral fracture. Twenty-two fractures were treated with internal fixation and six with arthroplasty. The overall mortality rate was 29% at a median of 15 months post fracture. The failure rate of intra-capsular fractures fixed with cannulated screws was 56% at a median time of 43 days. All patients had a reduction in mobility compared to their pre-operative function. The reduction in mobility was greatest in patients with intra-capsular fractures treated with cannulated screw fixation. Alcohol dependent patients sustaining a fracture of the proximal femur are significantly younger than non-alcohol dependent patients sustaining the same injury. Despite the younger age at presentation the one year mortality rate of this group was high (29%). The high rate of complications with fracture fixation and high one year mortality suggest that hemiarthroplasty may be the best treatment option for intra-capsular fractures in this patient group.