Comparison of continuous intravenous lidocaine versus transversus abdominis plane block for kidney transplant surgery: a randomized, non-inferiority trial

BACKGROUND AND OBJECTIVES

Transversus abdominis plane (TAP) blocks are associated with an improvement in postoperative analgesia following kidney transplant surgery. However, these blocks carry inherent risk and require a degree of expertise to perform successfully. Continuous intravenous lidocaine may be an effective alternative. In this randomized, non-inferiority study, we hypothesized that a continuous lidocaine infusion provides similar postoperative analgesia to a TAP block.

METHODS

Subjects presenting for kidney transplant surgery were randomized in a 1:1 ratio to either an ultrasound-guided unilateral, single-injection TAP block (TAP group) or a continuous infusion of lidocaine (Lido group). The primary outcome of this non-inferiority study was opioid consumption within the first 24 hours following surgery. Secondary outcomes included pain scores, patient satisfaction, opioid-related adverse events, time to regular diet, and persistent opioid use.

RESULTS

One hundred and twenty subjects, 59 from the TAP group and 61 from the Lido group, completed the study per protocol. Analysis of the primary outcome showed a cumulative geometric mean intravenous morphine equivalent difference between the TAP (14.6±3.2 mg) and Lido (15.9±2.4 mg) groups of 1.27 mg (95% CI -4.25 to 6.79; p<0.001), demonstrating non-inferiority of the continuous lidocaine infusion. No secondary outcomes showed clinically meaningful differences between groups.

CONCLUSIONS

This study demonstrates that a continuous infusion of lidocaine offers non-inferior postoperative analgesia compared with an ultrasound-guided unilateral, single-injection TAP block in the first 24 hours following kidney transplant surgery.

TRIAL REGISTRATION NUMBER

NCT03843879.

Nesprin-2-dependent ERK1/2 compartmentalisation regulates the DNA damage response in vascular smooth muscle cell ageing

Prelamin A accumulation and persistent DNA damage response (DDR) are hallmarks of vascular smooth muscle cell (VSMC) ageing and dysfunction. Although prelamin A is proposed to interfere with DNA repair, our understanding of the crosstalk between prelamin A and the repair process remains limited. The extracellular signal-regulated kinases 1 and 2 (ERK1/2) have emerged as key players in the DDR and are known to enhance ataxia telangiectasia-mutated protein (ATM) activity at DNA lesions, and in this study, we identified a novel relationship between prelamin A accumulation and ERK1/2 nuclear compartmentalisation during VSMC ageing. We show both prelamin A accumulation and increased DNA damage occur concomitantly, before VSMC replicative senescence, and induce the localisation of ERK1/2 to promyelocytic leukaemia protein nuclear bodies (PML NBs) at the sites of DNA damage via nesprin-2 and lamin A interactions. Importantly, VSMCs treated with DNA damaging agents also displayed prelamin A accumulation and ERK compartmentalisation at PML NBs, suggesting that prelamin A and nesprin-2 are novel components of the DDR. In support of this, disruption of ERK compartmentalisation at PML NBs, by either depletion of nesprin-2 or lamins A/C, resulted in the loss of ATM from DNA lesions. However, ATM signalling and DNA repair remained intact after lamins A/C depletion, whereas nesprin-2 disruption ablated downstream Chk2 activation and induced genomic instability. We conclude that lamins A/C and PML act as scaffolds to organise DNA-repair foci and compartmentalise nesprin-2/ERK signalling. However, nesprin-2/ERK signalling fidelity, but not their compartmentalisation at PML NBs, is essential for efficient DDR in VSMCs.

Retrospective cost analysis of cervical laminectomy and fusion versus cervical laminoplasty in the treatment of cervical spondylotic myelopathy

Background

Cervical laminoplasty (CLP) and posterior cervical laminectomy and fusion (CLF) are well-established surgical procedures used in the treatment of cervical spondylotic myelopathy (CSM). In situations of clinical equipoise, an influential factor in procedural decision making could be the economic effect of the chosen procedure. The object of this study is to compare and analyze the total hospital costs and charges pertaining to patients undergoing CLP or CLF for the treatment of CSM.

Methods

We performed a retrospective review of 81 consecutive patients from a single institution; 55 patients were treated with CLP and 26 with CLF. CLP was performed via the double-door allograft technique that does not require implants, whereas laminectomy fusion procedures included metallic instrumentation. We analyzed 10,682 individual costs (HC) and charges (HCh) for all patients, as obtained from hospital accounting data. The Current Procedural Terminology codes were used to estimate the physicians’ fees as such fees are not accounted for via hospital billing records. Total cost (TC) therefore equaled the sum of the hospital cost and the estimated physicians’ fees.

Results

The mean length of stay was 3.7 days for CLP and 5.9 days for CLF (P < .01). There were no significant differences between the groups with respect to age, gender, previous surgical history, and medical insurance. The TC mean was $17,734 for CLP and $37,413 for CLF (P < .01). Mean HCh for CLP was 42% of that for CLF, and therefore the mean charge for CLF was 238% of that for CLP (P < .01). Mean HC was $15,426 for CLP and $32,125 for CLF (P < .01); the main contributor was implant cost (mean $2582).

Conclusions

Our study demonstrates that, in clinically similar populations, CLP results in reduced length of stay, TC, and hospital charges. In CSM cases requiring posterior decompression, we demonstrate CLP to be a less costly procedure. However, in the presence of neck pain, kyphotic deformity, or gross instability, this procedure may not be sufficient and posterior CLF may be required.

An incidence of anteroinferior cerebellar artery/posteroinferior cerebellar artery anatomic variants penetrating the subarcuate fossa dura: operative technique and identification with 3-dimensional fast imaging employing steady-state acquisition magnetic resonance imaging

OBJECTIVE

This case series reports an incidence of anomalous vascular anatomy within the cerebellopontine angle. The relevant literature effectively describes techniques for mobilization yet underestimates the incidence. There has been no literature on the use of magnetic resonance imaging (MRI) to preoperatively identify this anatomic variant.

METHODS

We identify 8 cases of anomalous vascular anatomy within the cerebellopontine angle over a period of 6 years. They were uniformly identified through a retrosigmoid approach. Retrospective review of available 3-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) sequences was performed. Intraoperative video capture of technique for mobilization was obtained. Institutional neurosurgical database review identified retrosigmoid craniotomies performed by the senior surgeon.

RESULTS

We identify 8 of 192 cases (4.2%) as having this anomalous vascular anatomy. This aberrant vascular loop resulted in subtotal resection in 3 of 8 cases (37.5%) and significant morbidity in 1 of 8 cases (12.5%). The retrospective review of the 3D-FIESTA MRI sequences positively identified this aberrant vascular course in 5 of 5 cases (100%). The digital video recording is of high quality and demonstrates proper technique for mobilization.

CONCLUSION

The presence of this vessel creates the potential for technical difficulty and significant complications. We report the incidence and techniques of mobilization. This variant can potentially be identified on preoperative 3D-FIESTA MRI sequences. Knowledge of this anatomy may guide neurosurgeons in their case preparation.

Morphine infusions after pediatric cranial surgery: a retrospective analysis of safety and efficacy

INTRODUCTION

Morphine infusions are avoided after cranial surgery in children due to concerns of masking neurological deterioration and because cranial surgery is considered less painful than other surgical procedures. Studies indicate that up to 60% of patients experience moderate to severe pain after craniotomies. Morphine has demonstrated efficacy in the treatment of acute postoperative pain, yet codeine phosphate is commonly preferred as the standard treatment. We assessed the efficacy and safety of intravenous morphine use outside the intensive care unit (ICU) following cranial surgery in children.

METHODS

A retrospective case series analysis was conducted of medical records for 71 children. The patients underwent either cranial reconstruction (2002-2007) or supratentorial/infratentorial craniotomies (2005-2007) at British Columbia Children's Hospital. Comparison was made between patients receiving a continuous morphine infusion (CMI) and patients receiving acetaminophen and codeine. Patients were assessed for pain control and adverse events.

RESULTS

Thirty-seven children received CMI on the unit (30 cranial reconstruction and seven craniotomy), while 34 (10 cranial reconstruction and 24 craniotomy) received acetaminophen and codeine. There was no statistical difference in pain control. There was a statistically significant difference in nausea on postoperative day one (p = 0.002).

CONCLUSIONS

These findings suggest that CMI is as safe a treatment option as acetaminophen and codeine. Careful observation enables nurses to safely administer a CMI for children following cranial surgery on a surgical unit setting.

Spinal 2-Chloroprocaine: The Effect of Added Dextrose

Spinal 2-chloroprocaine is being investigated as an alternative short-acting spinal anesthetic to replace lidocaine for outpatient surgery. Adding dextrose increases the baricity of solutions and alters the characteristics of spinal anesthesia. In this study, we compared 2-chloroprocaine spinal anesthesia performed with or without the addition of dextrose (1.1%). Eight volunteers underwent 2 spinal anesthetics, receiving 40 mg 2-chloroprocaine (2 mL, 2%) with 0.25 mL saline with one and 0.25 mL 10% dextrose with the other in a double-blinded, randomized, balanced crossover manner. Pinprick anesthesia, tolerance to transcutaneous electrical stimulation, and tourniquet, motor strength measurements, and time to ambulation and void were assessed. Postvoid residual bladder volume was measured via ultrasound. Spinal anesthesia was successful in all subjects and regressed within 110 (80-110) min. There was no significant difference in peak height T4 (T7-C6), time to achieve peak block height (14 +/- 6 min), time for 2-segment regression (44 +/- 9 min), regression to L1 (66 +/- 12 min), tolerance of tourniquet (43 +/- 9 min), or return of motor function (81 +/- 14 min). Mean postvoid residual volume was larger with dextrose (74 +/- 67 mL versus 16 +/- 35 mL; P = 0.02). No subject reported signs of transient neurologic symptoms (TNS). In conclusion, spinal 2-chloroprocaine provides adequate potency with reliable regression, seemingly without TNS. Adding dextrose does not significantly alter spinal block characteristics but increases residual bladder dysfunction. Therefore, the addition of glucose to 2-chloroprocaine for spinal anesthesia is not necessary.

IMPLICATIONS

Spinal chloroprocaine provides adequate potency with reliable regression, seemingly without concerns of transient neurologic symptoms, and hence an appealing profile for outpatient surgery. The addition of dextrose does not alter peak block height or tolerance of thigh tourniquet, and increases the degree of residual bladder dysfunction.

Novel proteins linking the actin cytoskeleton to the endocytic machinery in Saccharomyces cerevisiae

The importance of coupling the process of endocytosis to factors regulating actin dynamics has been clearly demonstrated in yeast, and many proteins involved in these mechanisms have been identified and characterized. Here we demonstrate the importance of two additional cortical components, Ysc84p and Lsb5p, which together are essential for the organization of the actin cytoskeleton and for fluid phase endocytosis. Both Ysc84p and Lsb5p were identified through two-hybrid screens with different domains of the adaptor protein Sla1p. Ysc84p colocalizes with cortical actin and requires the presence of an intact actin cytoskeleton for its cortical localization. Ycl034w/Lsb5p localizes to the cell cortex but does not colocalize with actin. The Lsb5 protein contains putative VHS and GAT domains as well as an NPF motif, which are all domains characteristic of proteins involved in membrane trafficking. Deletion of either gene alone does not confer any dramatic phenotype on cells. However, deletion of both genes is lethal at elevated temperatures. Furthermore, at all temperatures this double mutant has depolarized actin and an almost undetectable level of fluid phase endocytosis. Our data demonstrate that Ysc84p and Lsb5p are important components of complexes involved in overlapping pathways coupling endocytosis with the actin cytoskeleton in yeast.