Diabetes Mellitus, Independent of Body Mass Index, Is Associated With a "Higher Success" Rate for Supraclavicular Brachial Plexus Blocks

The duration of sciatic nerve block with local anesthetics is longer in diabetic compared with nondiabetic rats. A small, but statistically significant, increase in nerve damage occurred in diabetic rats after nerve block with ropivacaine alone or when duration of lidocaine block was extended with clonidine. These findings may have implications for dosing of local anesthetics in diabetic patients undergoing regional analgesia with nerve blocks.

Section: Discussionmentioning

confidence: 91%

Local Anesthetic Sciatic Nerve Block and Nerve Fiber Damage in Diabetic Rats

Buvanendran

Williams

Wagenaar³

et al. 2010

“…29 Although animal studies have consistently found that diabetic nerves are more sensitive to local anesthetics and potentially more susceptible to neural injury, it is unclear whether diabetic patients have a higher incidence of neurologic injury after regional anesthesia. 17,25,26,30 There is limited clinical data suggesting that the success of peripheral nerve blockade (supraclavicular brachial plexus) may be higher in diabetic patients independent of other predictors of success (eg, body mass index) compared with nondiabetic patients. 31,32 Gebhard and colleagues 30 propose several theories for this finding, including (1) a higher sensitivity of diabetic nerve fibers to local anesthetics, (2) possible unknown intraneural penetration before injection, and (3) preexisting DPN with accompanying decreased sensation.…”

Section: Diabetic Polyneuropathymentioning

confidence: 99%

Regional Anesthesia in Patients With Preexisting Neurologic Disease

Kopp

Jacob

Hebl

2015

Since publication of initial recommendations in 2008, there is limited new information regarding the performance of regional anesthesia in patients with preexisting neurologic diseases. However, the strength of evidence has increased since 2008 regarding (1) the concern that diabetic nerves are more sensitive to local anesthetics and perhaps more susceptible to injury and (2) the concern that performing neuraxial anesthesia and analgesia in patients with preexisting spinal canal pathology may increase the risk of new or worsening neurologic symptoms. This increased evidence reinforces our initial recommendations. In addition, since the initial recommendations in 2008, the concept of postsurgical inflammatory neuropathy has been described and is potentially a contributor to postoperative neurologic dysfunction.

“…However, US may particularly improve nerve localization and perhaps reduce nerve injury in patients with diabetes mellitus, in whom PNS-or paresthesia-guided localization is insensitive, and whose nerves have an altered response to local anesthetics. 48,49 Fewer needle passes and vascular punctures may also limit hematoma formation in anticoagulated patients, in whom deeper peripheral nerve blocks are relatively contraindicated. 50 Finally, UGRAfacilitated reduction in local anesthetic volume may have a much greater benefit for the pediatric patient than the adult patient.…”

Section: Limitations and Future Directionsmentioning

confidence: 99%

Ultrasound-Guided Regional Anesthesia and Patient Safety

Neal¹

2010

205

The role of ultrasound-guided regional anesthesia (UGRA) in reducing the frequency of regional anesthetic-related complications is difficult to ascertain from analyzing the limited literature on the topic. This evidence-based review critically evaluates the contributions of UGRA to improved patient safety, particularly as compared with standard nerve localization tools. Randomized controlled trials that compared UGRA with another form of neural localization and case series of more than 500 patients were used to compare safety parameters. The quality of studies and strength of evidence were graded. Of those randomized controlled trials identified by our search techniques, 22 compared the incidence of postoperative nerve symptoms, 17 assessed local anesthetic systemic toxicity parameters, and 3 studied hemidiaphragmatic paresis. Statistical proof for meaningful reduction in the frequency of extremely rare complications, such as permanent peripheral nerve injury, is likely unattainable. Although there is evidence for UGRA reducing the occurrence of vascular puncture and the frequency of hemidiaphragmatic paresis, as yet there is at best inconclusive scientific proof that these surrogate outcomes are linked to actual reduction of their associated complications, such as local anesthetic systemic toxicity or predictable diaphragmatic impairment in at-risk individuals. This evidence-based review thus strives to summarize both the power and the limitations of UGRA as a tool for improving patient safety.