The risk of sedation/analgesia in hemodialysis patients undergoing interventional procedures

Anesthetic effect of ultrasound-guided block of the musculocutaneous nerve during endovascular treatment of dysfunctional radiocephalic arteriovenous fistulas

BACKGROUND

Delivering requisite and minimal anesthesia for endovascular treatment (EVT) of dysfunctional arteriovenous fistulas (AVFs) under the target nerve block can achieve reasonable analgesia. We evaluated the anesthetic efficacy of ultrasound (US)-guided selective block of the musculocutaneous nerve (MCN) during the EVT of runoff venous strictures in the forearm through the radiocephalic (RC)-AVF at the wrist or the anatomical snuff box and analyzed the factors inhibiting the analgesia achieved under the MCN block.

METHODS

We enrolled 30 adult patients undergoing hemodialysis who had received 78 EVT sessions in an outpatient clinic mainly for long and/or multiple outflow-venous strictures in the forearm under US-guided blocks of the MCN, which provides sensory innervation to the anterolateral forearm where the cephalic vein courses. We assessed patients' pain during balloon dilations using the Wong-Baker FACES® Pain Rating Scale (WBFRS) and evaluated the factors increasing the pain (WBFRS score ⩾4), including patient characteristics, dilated strictures, additional nerve blocks, and types of balloon catheters.

RESULTS

In 25 EVT sessions (32.1%) out of 78 sessions, patients complained of stronger pain (WBFRS score ⩾4), while in the other 53 sessions (67.9%), presented with no pain and slight pain (WBFRS score = 0 or 2). Univariate analysis clarified that dilation of the AVF anastomosis, presence of dilated stenosis >4 cm, and a single block of the MCN or its sensory terminal significantly triggered more pain (p < 0.05). Consequently, multivariate analysis of all the factors with p < 0.1 in the univariate analysis, including multiple dilated stenosis sites, demonstrated that dilation of the AVF anastomosis significantly caused severe pain despite the anesthesia of the MCN block (p < 0.05).

CONCLUSION

US-guided selective block of the MCN could be a leading anesthetic option for EVT for multiple long stenoses of the cephalic vein draining through the RC-AVF in the wrist or anatomical snuff box.

Interventional Nephrology: Opportunities and Challenges

The nephrologist has a pivotal role as the leader of multidisciplinary teams to optimize vascular access care of the patient on dialysis and to promote multidisciplinary collaboration in research, training, and education. The continued success of interventional nephrology as an independent discipline depends on harnessing these efforts to advance knowledge and encourage innovation. A comprehensive curriculum that encompasses research from bench to bedside coupled with standardized clinical training protocols are fundamental to this expansion. As we find ourselves on the threshold of a much-awaited revolution in nephrology, there is great opportunity but also formidable challenges in the field - it is up to us to work together to realize the enormous potential of our discipline.

Continuous intravenous versus intermittent bolus midazolam with remifentanil during arteriovenous fistula placement with monitored anesthesia care in chronic renal failure patients: a randomized controlled trial

BACKGROUND

There is limited data on the use of intravenous continuous infusion (CI) versus intravenous intermittent bolus (IB) doses of midazolam for conscious sedation in patients with chronic renal failure. Unexpected adverse events can occur in chronic renal failure patients undergoing short procedures.

OBJECTIVE

Investigate and compare the sedoanalgesic and adverse effects of intravenous continuous infusion (CI) use of midazolam with intravenous intermittent bolus (IB) doses of midazolam while using intravenous remifentanil as a rescue medication, and assess patient and surgeon satisfaction.

DESIGN

Prospective, randomized, single-blind controlled study.

SETTINGS

Two tertiary care hospitals.

PATIENTS AND METHODS

Study included patients aged 43-81 years with a diagnosis of chronic renal failure who were referred for an arteriovenous fistula procedure with modified anesthesia care between August 2012 and April 2016. The patients were randomized to intravenous CI or IB doses of midazolam. IB doses of remifentanil were used as a rescue medication.

MAIN OUTCOME MEASURES

Primary outcomes were amounts of midazolam and remifentanil medications during the operation, the amount of remifentanil as a rescue medication, and the satisfaction of patient and surgeon.

SAMPLE SIZE

116 assessed for eligibility; 99 randomized to CI (n=50) or IB doses (n=49 of midazolam).

RESULTS

The total dose of midazolam by CI was greater than with midazolam by IB (P=.002). The total dose of remifentanil was higher with IB doses of midazolam in comparison to CI of midazolam (P=.001). The groups were similar in sedation and pain control, duration of procedure, recovery time, patient satisfaction and adverse events; surgeon satisfaction was greater with CI versus IB (P=.035).

CONCLUSION

Intravenous CI midazolam during MAC provides better surgeon satisfaction then IB midazolam and can be used safely for arteriovenous fistula procedures.

LIMITATIONS

Two different surgeon groups.

CONFLICT OF INTEREST

None.

Renal impairment and analgesia: From effectiveness to adverse effects

Kidney pain is one of the clinically significant features of renal dysfunction. Mild to severe pain is seen in the lower back area. Painkillers are mostly recommended in these cases to relieve the symptom. Yet, several analgesics are associated with side effects that can worsen the state of the disease. This review is based on the studies conducted in these aspects analgesics used to treat kidney pain and their effectiveness, renal consequences of postoperative analgesia, and pharmacogenetics of these palliatives are briefly summarized in this paper.

Changes in the Profile of Endovascular Procedures Performed in Freestanding Dialysis Access Centers over 15 Years

BACKGROUND AND OBJECTIVES

Marked changes occurred in the vascular access profile of patients receiving hemodialysis in the United States over the 15-year period of 2001-2015. This study was undertaken to evaluate how these changes have affected dialysis access maintenance and salvage procedures performed in freestanding dialysis access centers and to examine the effectiveness, efficiency, and safety of these procedures in this setting.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data were collected from freestanding, dedicated dialysis access centers operating under a common system of management. Data were available on 689,676 dialysis access procedures. Data relating to case mix, procedure outcome, procedural time, and intraprocedural and immediate postprocedural complications were analyzed.

RESULTS

The arteriovenous procedure profile changed from one characterized by approximately equal numbers of angioplasties and thrombectomies performed on arteriovenous grafts (AVGs) to one characterized primarily by angioplasties performed on arteriovenous fistulas. The percentage of angioplasties performed throughout the study was significantly greater than thrombectomies, with a mean of 67.9% versus 32.1% (P<0.001). Interventional procedures did not decrease with increasing arteriovenous fistula utilization in prevalent patients receiving dialysis. The incidence roughly paralleled the increasing prevalence of this type of access. A decreasing percentage of AVG utilization resulted in a progressive, roughly parallel, but disproportionately higher, decrease in the percentage of AVG procedures (P<0.001). A progressive improvement in procedure outcomes and a decrease in complication rates and procedure times were observed (P<0.001 for each). A progressive decrease in tunneled dialysis catheter placement was also observed.

CONCLUSIONS

The procedure profile treated in freestanding, dedicated dialysis access centers changed significantly over 15 years, reflecting the changes that have occurred in the vascular access profile of the dialysis population.

Role of interventional nephrology in the multidisciplinary approach to hemodialysis vascular access care

Dialysis vascular access planning, creation, and management is of critical importance to the dialysis patient population. It requires a multidisciplinary approach involving patients and their families, dialysis facility staff, the nephrologist, the surgeon, and the interventionalist. With the emergence of interventional nephrology as a subspecialty of nephrology, the nephrologist is increasingly providing both the nephrology and interventional aspects of care, and in some areas, the surgical functions as well. Most of these interventional nephrologists work in freestanding outpatient dialysis access centers (DACs). Large clinical studies published over the past 10 years demonstrate that the interventional nephrologist can manage the problems associated with dialysis access dysfunction effectively, safely, and economically. A recently published study based upon United States Medicare claims data in which a DAC patient group (n = 27,613) and a hospital outpatient department patient group (HOPD group; n = 27,613) were compared using propensity score matching techniques showed that patients treated in the DACs had significantly better clinical outcomes (P<0.001). This included fewer vascular access-related infections (0.18 vs. 0.29), fewer septicemia-related hospitalizations (0.15 vs. 0.18), and a lower mortality rate (47.9% vs. 53.5%).

Effect of low dose dexmedetomidine premedication on propofol consumption in geriatric end stage renal disease patients

BACKGROUND AND OBJECTIVE

Sedation in dialysis dependent end-stage renal disease patients requires caution as a result of performing high doses of sedatives and its complications. Multidrug sedation regimens might be superior and advantage on lesser drug consumption and by the way adverse events which occur easily in end-stage renal disease patients. We evaluated the effects of dexmedetomidine premedication on propofol consumption, sedation levels with Observer's Assessment of Alertness and Sedation scores and the bispectral index and the hemodynamic changes, potential side effects in geriatric patients with end-stage renal disease who underwent hip fracture surgery under spinal anesthesia.

METHOD

In this randomized, controlled, double-blind study 60 elderly patients (age≥65 years) with end-stage renal disease and hip fracture scheduled for anterograde femoral intramedullary nailing were assigned to groups that received either intravenous saline infusion (Group C) or dexmedetomidine 0.5μg/kg/10min infusion for premedication (Group D). All the patients received propofol infusion after the induction of the spinal anesthesia.

RESULTS

Total propofol consumption, propofol dose required for targeted sedation levels according to Observer's Assessment of Alertness and Sedation scores and bispectral index levels, recovery times were significantly lower in Group D (p<0.001). The time to reach to Observer's Assessment of Alertness and Sedation score 4 and to achieve bispectral index≤80 was significantly lower in Group C compared with Group D (p<0.001). Adverse events were similar in both groups.

CONCLUSION

Dexmedetomidine premedication lowers intraoperative propofol consumption to maintain targeted level of sedation. Therefore low dose dexmedetomidine premedication in addition to propofol infusion might be an alternative in geriatric patients with end-stage renal disease for sedation.