A Systematic Review on Long-Term Postsurgical Pain Outcomes; What Is the Effect of Upper Extremity Regional Anesthesia?

BACKGROUND: Chronic pain is a recognized complication of surgery, and it has been hypothesized that regional anesthesia might reduce the risk of development of chronic pain after upper extremity surgery. METHODS: A systematic literature review was performed to assess whether in patients undergoing elective upper extremity surgery (P), regional anesthesia (I), compared to general anesthesia (C), would result in lower long-term (>3 months) postoperative pain intensity (O). We included randomized and nonrandomized controlled trials (RCTs). Our primary outcome was numerical rating score or visual analogue scale for pain, at >3 months postoperatively. The Embase, Medline ALL, Web of Science Core Collections, Cochrane Central Register of Controlled Trials, and Google Scholar databases were searched for all reports assessing pain at >3 months after upper extremity surgery under general versus regional anesthesia. Secondary outcomes were: opioid prescription filling, complex regional pain syndrome (CRPS) incidence, the Mayo Wrist Score (MWS), and scores on the Disability of the Arm, Shoulder and Hand (DASH) questionnaire. Quality (or certainty) of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Risk-of-bias was assessed using the Cochrane tool for randomized trials (RoB 2.0) and nonrandomized trials (ROBINS-I). RESULTS: This review included 14 studies, comprising 7 RCTs and 7 nonrandomized studies. Six of the 7 studies (4 RCTs, N = 273; 2 nonrandomized studies, N = 305) using a pain score, our primary outcome, report comparable long-term postoperative pain scores after regional and general anesthesia. Six of the 7 studies using our secondary outcomes report comparable long-term outcomes in terms of opioid prescription filling (2 retrospective cohort studies [RCSs], N = 89,256), CRPS incidence (1 RCT, N = 301), MWS (1 RCT and 1 RCS, N = 215), and DASH score (1 RCT, N = 36). Comparable outcomes were reported in all 7 RCTs (N = 778) and in 5 of the 7 nonrandomized studies, comprising 5 RCSs (N = 89,608). Two prospective observational studies (POSTs), comprising 279 patients, report a statistically significant difference in outcomes, with less pain and better DASH scores after brachial plexus anesthesia. All 14 studies provided moderate to very low certainty evidence, and there was a serious risk of bias due to confounding bias in 5 of the 7 nonrandomized studies (N = 631). CONCLUSIONS: The results of this review indicate that upper extremity regional anesthesia, compared to general anesthesia, is unlikely to change pain intensity at >3 months postoperatively.

Regional anaesthesia is associated with less patient satisfaction compared to general anaesthesia following distal upper extremity surgery: a prospective double centred observational study.

BACKGROUND: Patient satisfaction is a well-established indicator to evaluate the quality of medical care and there is an increasing support for the use of patient-reported experience measures (PREMs) to evaluate satisfaction. To anesthetize the upper limb for surgery, both general and regional plexus anaesthesia are appropriate techniques. However, the best technique in the anaesthesiologist's perspective might not necessarily result in the highest patient satisfaction. The aim of this study is to investigate patient satisfaction following general and regional anaesthesia, and to identify areas where anaesthesiologists can focus on improving patient care. METHODS: Patients scheduled for elective distal upper extremity surgery under either general or regional plexus anaesthesia were prospectively included. On the first postoperative day, patient satisfaction and main reason for dissatisfaction with the anaesthesia technique were investigated during a telephone interview. RESULTS: Of the 243 patients included in the current study, 79.8% report being "fully satisfied" with their anaesthesia technique. 32.1% of the patients who received regional anaesthesia reported not feeling "fully satisfied". This figure is 5.5% following general anaesthesia. Main reason for dissatisfaction following regional anaesthesia are reported as "insufficient anaesthesia prior to surgery", and "the discomfort of having a long-lasting insensate extremity postoperatively". CONCLUSIONS: Following regional plexus anaesthesia, a third of the patients are not "fully satisfied". To optimize patient satisfaction following regional anaesthesia techniques, we advocate stronger focus on patient counselling preoperatively, addressing the issues of block failure and prolonged postoperative sensory and motor block.

Neural correlates of the LSD experience revealed by multimodal neuroimaging.

Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD's marked effects on the visual cortex did not significantly correlate with the drug's other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of "ego-dissolution" and "altered meaning," implying the importance of this particular circuit for the maintenance of "self" or "ego" and its processing of "meaning." Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others.

Incidence of Chronic Postsurgical Pain after Upper Extremity Surgery and its Correlation with Preoperative Pain.

The incidence of chronic postsurgical pain (CPSP) after upper extremity surgery is not known. The goal was to study CPSP at 5 years postoperative and to investigate patient, surgical, and anesthetic risk factors. Methods: Patients scheduled for elective upper extremity surgery were included, and numeric rating scale (NRS) score for pain was obtained preoperatively and at 5 years postoperatively. According to the International Association for the Study of Pain definition, CPSP was defined as an increase in NRS compared with preoperatively. Results: A total 168 patients were contacted at 5 years postoperatively. Incidence of CPSP was 22%, and 35% had an NRS score of 4 or more. The number of patients with an NRS score of 0 and with an NRS score of 4 or more preoperatively was higher in the no-CPSP group, with P values of 0.019 and 0.008, respectively. Of the patients with no preoperative pain, 34% developed CPSP. Regional anesthesia was associated with a lower CPSP incidence (P = 0.001) and was more frequently applied in surgery on bony structures and in patients with a preoperative NRS score of 4 or more. Conclusions: The incidence CPSP was 22%. Patients with no pain or an NRS score of 4 or more preoperatively were less likely to develop CPSP, but individual susceptibility to pain and success of the surgery may be of influence. One-third of the patients with no preoperative pain developed CPSP. More studies are needed to reveal the exact relation between brachial plexus anesthesia and CPSP.

Is It the Surgery or the Block? Incidence, Risk Factors, and Outcome of Nerve Injury following Upper Extremity Surgery.

Although numerous studies have addressed the topic of postoperative nerve injury, debate continues to exist on its exact incidence, risk factors, etiology, and functional outcome. The aim of this study is to investigate the incidence of nerve injury and to identify patient, anesthetic, and surgical factors pertaining to perioperative nerve injury. Also, long-term nerve injury outcomes were assessed in terms of functionality. METHODS: A total of 297 patients, scheduled for elective distal upper extremity surgery, were prospectively included. At various time points, patients were screened for new onset nerve injury by means of clinical examination and questionnaires (including the Quick Disabilities of the Arm, Shoulder and Hand functionality measure). RESULTS: New nerve injury was diagnosed in 14 patients [4.7% (95% CI, 2.8-7.8)], but no causative risk factors were identified. The exact origin of nerve injury is suspected to be surgical in 11 cases. At 4 years postoperatively, 5 of the 14 patients with nerve injury (36%) were still symptomatic and had reduced functionality relative to preoperative status. CONCLUSIONS: This study demonstrates an incidence of all cause nerve injury of 4.7%. No specific patient, anesthetic, or surgical risk factors are identified and, importantly, patients who received regional anesthesia are not at more risk of nerve injury than those who received general anesthesia. The exact origin of nerve injury is very difficult to determine, but is suspected to be caused by direct surgical trauma in most cases. Four years following the nerve injury, approximately 40% of the patients with new onset nerve injury have reduced functionality.

Individual duration of axillary brachial plexus block is unpredictable: a prospective double centered observational study.

BACKGROUND: The duration of effect for axillary plexus block using ropivacaine is highly variable. The available literature does not offer any plausible means of predicting time of block offset for individual patients, making it difficult to give accurate information and plan postoperative analgesics. This study was designed to identify factors influencing axillary plexus block offset time. METHODS: A total of 92 patients participated in this prospective double centred observational study. All patients were scheduled for axillary plexus block with ropivacaine 0.75% and subsequent block duration was recorded. RESULTS: Mean time of axillary plexus block offset was 13.5 hours, with a range of 4.8 to 25.4 hours. No statistical significant differences in offset time was seen with regard to gender, age, body weight, BMI and ASA-classification. A trend for increasing duration of blocks associated with increasing age was observed. No statistically significant difference was identified in block duration between blocks performed with nerve stimulator guidance versus ultrasound guidance. Similarly, neither dose nor volume of ropivacaine 0.75% was identified as a factor influencing block duration. CONCLUSIONS: This prospective study demonstrates a large inter individual variation in time of axillary plexus block offset using ropivacaine 0.75%. The lack of association between offset time and both demographic and block performance factors, makes predictability of individual duration of axillary plexus blocks in clinical practice extremely difficult. We suggest that all patients should be made aware of such variability in duration prior to block placement.

The effects of AMPA blockade on the spectral profile of human early visual cortex recordings studied with non-invasive MEG.

The generation of gamma-band (>30 Hz) cortical activity is thought to depend on the reciprocal connections of excitatory glutamatergic principal cells with inhibitory GABAergic interneurons. Both in vitro and in vivo animal studies have shown that blockade of glutamatergic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors reduces the amplitude of gamma-band activity. In this registered report, we hypothesised that similar effects would be observed in humans following administration of perampanel, a first in class AMPA antagonist, used in the treatment of epilepsy. In a single-blind placebo-controlled crossover study, 20 healthy male participants completed two study days. On one day participants were given a 6 mg dose of perampanel and on the other an inactive placebo. magnetoencephalography (MEG) recordings of brain activity were taken before and two hours after drug administration, with activity in the visual cortex probed using a stimulation protocol known to induce gamma-band activity in the primary visual cortex. As hypothesised, our results indicated a decrease in gamma-band amplitudes following perampanel administration. The decreases in gamma-band amplitudes observed were temporally restricted to the early time-period of stimulus presentation (up to 400 msec) with no significant effects observed on early evoked responses or alpha rhythms. This suggests that the early time-window of induced visual gamma-band activity, thought to reflect input to the visual cortex from the lateral geniculate nucleus, is most sensitive to AMPA blocking drugs.

Safety Concerns About an Epidural Blood Patch in a Patient with Extensive Epidural Fluid Accumulation.

We present a case of postdural puncture headache in a patient with extensive epidural fluid accumulation. An initial epidural blood patch was aborted because of concern about increased risk of complications. After magnetic resonance imaging, we proceeded with epidural blood patch with a good therapeutic result. We discuss the imaging results and safety concerns we considered when assessing the benefits and risks of epidural blood patch in this patient.

In Critically Ill Patients, Serum Procalcitonin Is More Useful in Differentiating between Sepsis and SIRS than CRP, Il-6, or LBP.

We studied the usefulness of serum procalcitonin (PCT), interleukin-6 (IL-6), lipopolysaccharide binding protein (LBP) levels and C-reactive protein (CRP) levels, in differentiating between systemic inflammatory response syndrome (SIRS) and sepsis in critically ill patients. Methods. In this single centre prospective observational study we included all consecutive patients admitted with SIRS or sepsis to the ICU. Blood samples for measuring CRP, PCT, IL-6 and LBP were taken every day until ICU discharge. Results. A total of 76 patients were included, 32 with sepsis and 44 with SIRS. Patients with sepsis were sicker on admission and had a higher mortality. CRP, PCT, IL-6 and LBP levels were significantly higher in patients with sepsis as compared to SIRS. With PCT levels in the first 24 hours after ICU admission <2 ng/mL, sepsis was virtually excluded (negative predictive value 97%). With PCT >10 ng/mL, sepsis with bacterial infection was very likely (positive predictive value 88%). PCT was best at discriminating between SIRS and sepsis with the highest area under the ROC curve (0.95, 95% CI 0.90-0.99). Discussion. This study showed that PCT is more useful than LBP, CRP and IL-6 in differentiating sepsis from SIRS.