Prolongation of spinal duration by escalating doses of intrathecal epinephrine in lower limb arthroplasty

Aim: The optimal dose of low-dose intrathecal epinephrine in the absence of intrathecal opioids is unknown. Materials & methods: Prospective, randomized, double blind clinical trial of patients undergoing lower limb arthroplasties. The primary end point was spinal block duration measured via motor and sensory block duration. Results: 30 patients undergoing lower limb arthroplasty were randomized into one of six groups with varying intrathecal epinephrine doses 0-100 mcg. There was a direct linear effect between motor block duration and intrathecal epinephrine dose with higher doses being associated with longer block duration (p = 0.011). Mean motor block duration was 3.74 ± 1.13, 3.36 ± 0.47, 3.39 ± 0.60, 4.06 ± 0.98 and 5.20 ± 1.41 h for the EPI0, EPI25, EPI50, EPI75 and EPI100 groups respectively. Conclusion: This study reveals that low-dose intrathecal epinephrine (75-100 mcg) in the absence of intrathecal opioids can be reliably used to prolong motor block duration in lower limb arthroplasty. Clinical Trial Registration: NCT02619409 (ClinicalTrials.gov).

Comparison of lateral quadratus lumborum and lumbar plexus blocks for postoperative analgesia following total hip arthroplasty: a randomized clinical trial

INTRODUCTION

Effective analgesia after total hip arthroplasty must minimize pain and optimize early ambulation. Lumbar plexus blocks (LPBs) provide analgesia but may cause motor weakness. Quadratus lumborum blocks (QLBs) may provide analgesia with preserved motor strength.

METHODS

This trial randomized subjects scheduled for elective hip arthroplasty to receive an LPB or lateral QLB for postoperative analgesia. The primary outcome was opioid consumption at 12-hour postoperative. Non-inferiority of lateral QLBs compared with LPBs was conducted using a one-sided two-sample t-test. Secondary outcomes included pain scores, cumulative opioid consumption, quadriceps strength, time to ambulation, and distance ambulated. Differences in pain scores and opioid consumption over time between groups were evaluated using a linear mixed model.

RESULTS

The trial consented and randomized 111 subjects and 103 completed the study: LPB (n=50) and lateral QLB (n=53). Mean (95% CI) cumulative opioid consumption (mg) at 12-hour postoperative was not found to be non-inferior in the lateral QLB (15.9 (12.7 to 19.2)) vs the LPB (12.7 (10.2 to 15.1)) group (p=0.625). Pain scores in postoperative anesthetic care unit (PACU) and 24-hour postoperative did not differ. The maximum distance ambulated did not differ, but lateral QLB patients were 2.4 times more likely to ambulate in the first 12 hours (p=0.024) and had significantly greater quadriceps strength in PACU (p<0.001).

DISCUSSION

Although we were unable to demonstrate non-inferiority for opioid consumption at 12-hour postoperative, strength and mobilization were improved in lateral QLB subjects.

TRIAL REGISTRATION NUMBER

NCT04402437.

Anesthetic Management of Severe Pulmonary Hypertension in Pregnancy

Pregnancy entails significant changes in maternal physiology that are not well-tolerated in patients with pulmonary arterial hypertension. The profound changes in plasma volume, cardiac output, and systemic vascular resistance can lead to increased strain placed on the right ventricle, leading to right-heart failure and cardiovascular collapse. Given the complex and sometimes opposing physiologic changes, managing these patients can be challenging. As such, these patients have a significantly increased reported maternal mortality rate. This report describes a parturient with newly diagnosed severe pulmonary arterial hypertension and her anesthetic management.

128-slice acceletated-pitch dual energy CT angiography of the head and neck: comparison of different low contrast medium volumes

BACKGROUND

Our study aims to evaluate the image quality and feasibility of 128-slice dual-energy CTA (DE-CTA) for supra-aortic arteries using reduced amounts of contrast medium (CM).

METHODS

A prospective study was performed in 54 patients receiving CTA of the head and neck with a 128-slice dual-source CT system. Patients were randomized into two groups with a volume of either 40 mL of CM (Group I) or 50 mL of CM (Group II). Arterial and venous enhancements were recorded for quantitative assessment. Qualitative assessments for images without bone removal (BR) were based on a) the visualization of the circle of Willis and b) streak artifacts due to residual CM in the subclavian or internal jugular veins ipsilateral to injection of CM. Qualitative assessment of dual-energy images using BR was based on the presence of bone remnants and vessel integrity. Quantitative data was compared using the Student t test. The χ(2) test was used for the qualitative measurements of streak artifacts in veins while the Mann-Whitney U test was used for the qualitative measurements of images with BR.

RESULTS

Arterial and venous attenuation was significantly higher in Group II (P=0.000). Image quality regarding the circle of Willis was excellent in both groups (3.90±0.30 for Group I and 4.00±0 for Group II) . Imaging of the internal jugular veins was scored higher in Group I (1.87±0.72) compared with Group II (1.48±0.51) (P=0.021). Within Group I using BR, mean scores for bone remnants did not differ significantly (P>0.05) but mean scores of vessel integrity (P<0.05) did.

CONCLUSIONS

Contrast-enhanced head and neck CTA is feasible using a scan protocol with low amounts of contrast medium (40 mL) on a 128-slice dual-energy CTA. The 40-mL protocol provides satisfactory image quality before and after dual-energy bone-removal post-processing.

Cardiovascular manifestations of heterotaxy and related situs abnormalities assessed with CT angiography

Heterotaxy and situs abnormalities describe an abnormal arrangement of visceral organs in the thoracoabdominal cavity across the normal left-right axis of the body. It is associated with a high occurrence of congenital heart and abdominal defects, including anomalous pulmonary venous connections, systemic venous abnormalities, asplenia, and intestinal malrotation. Without proper diagnosis and surgical intervention, the prognosis of patients with heterotaxy syndrome and associated congenital defects is extremely poor. Complex intracardiac and extracardiac lesions are common in heterotaxy and can be difficult to assess by echocardiography. CT angiography (CTA) is a useful tool in this setting to accurately assess intracardiac and extracardiac abnormalities in this population for medical or surgical management. The intention of this pictorial essay is to review the most common cardiovascular defects involved with heterotaxy syndrome in addition to emphasizing the utility of CTA in the identification and classification of anomalies seen in these patients. This review briefly defines most common terminology used in situs abnormalities as well as presents CT images and 3-dimensional reconstructions of common anomalies associated with situs abnormalities. In summary, this review should prepare radiologists and pediatric cardiologists to describe heterotaxy and situs abnormalities in addition to recognizing the utility of CTA in these patients.