André Wolff

Diagnostic lumbosacral segmental nerve blocks with local anesthetics: a prospective double-blind study on the variability and interpretation of segmental effects.

Background and Objectives Selective spinal nerve infiltration blocks are used diagnostically in patients with chronic low back pain radiating into the leg. Generally, a segmental nerve block is considered successful if the pain is reduced substantially. Hypesthesia and elicited paresthesias coinciding with the presumed segmental level are used as controls. The interpretation depends on a standard dermatomal map. However, it is not clear if this interpretation is reliable enough, because standard dermatomal maps do not show the overlap of neighboring dermatomes. The goal of the present study is to establish if dissimilarities exist between areas of hypesthesia, spontaneous pain reported by the patient, pain reduction by local anesthetics, and paresthesias elicited by sensory electrostimulation. A secondary goal is to determine to what extent the interpretation is improved when the overlaps of neighboring dermatomes are taken into account. Methods Patients suffering from chronic low back pain with pain radiating into the leg underwent lumbosacral segmental nerve root blocks at subsequent levels on separate days. Lidocaine (2%, 0.5 mL) mixed with radiopaque fluid (0.25 mL) was injected after verifying the target location using sensory and motor electrostimulation. Sensory changes (pinprick method), paresthesias (reported by the patient), and pain reduction (Numeric Rating Scale) were reported. Hypesthesia and paresthesias were registered in a standard dermatomal map and in an adapted map which included overlap of neighboring dermatomes. The relationships between spinal level of injection, extent of hypesthesia, location of paresthesias, and corresponding dermatome were assessed quantitatively. Comparison of the results between both dermatomal maps was done by paired t-tests. Results After inclusion, data were processed for 40 segmental nerve blocks (L2-S1) performed in 29 patients. Pain reduction was achieved in 43%. Hypesthetic areas showed a large variability in size and location, and also in comparison to paresthesias. Mean hypesthetic area amounted 2.7 ± 1.4 (± SD: range, 0 to 6; standard map) and 3.6 ± 1.8 (0 to 6; adapted map; P < .001) dermatomes. In these cases, hypesthesia in the corresponding dermatome was found in 80% (standard map) and 88% of the cases (adapted map, not significant). Paresthesias occurring in the corresponding dermatome were found in 80% (standard map) compared with 98% (adapted map, P < .001). In 85% (standard map) and 88% (adapted map), spontaneous pain was present in the dermatome corresponding to the level of local anesthetic injection. In 55% (standard map) versus 75% (adapted map, P < .005), a combination of spontaneous pain, hypesthesia, and paresthesias was found in the corresponding dermatome. Conclusions Hypesthetic areas determined after lumbosacral segmental nerve blocks show a large variability in size and location compared with elicited paresthesias. Confirmation of an adequately performed segmental nerve block, determined by coexistence of hypesthesia, elicited paresthesias and pain in the presumed dermatome, is more reliable when the overlap of neighboring dermatomes is taken into account.

Changed patterns in Dutch palliative sedation practices after the introduction of a national guideline.

BACKGROUND Continuous sedation, contrary to euthanasia, has been increasingly accepted among medical professionals worldwide. In the Netherlands, a national guideline for continuous palliative sedation has been developed to contribute to the quality of palliative sedation practice. The present follow-up study investigated whether the practice of continuous sedation has changed after the introduction of this guideline. METHODS This study compared the practice of continuous sedation before and after the introduction of the guideline on December 7, 2005. A baseline measurement was performed between February 1, 2003, and May 1, 2005, with an enrollment of 492 physicians (medical specialists, general practitioners, and nursing home physicians). From January 1 to June 30, 2007, after the introduction of a national guideline for palliative sedation, a follow-up study was performed with the respondents of the baseline study. Physicians were asked to report on their last case of deep and continuous sedation in the past 12 months. RESULTS This study reports the results of the follow-up study and compares them to the results of the baseline study. The response rate was 69.3% (n = 341). Of these physicians, 160 reported a last case of continuous sedation in both the baseline and the follow-up studies. Physicians reported a significant increase in patient involvement in decision making, from 72.3% to 82.2%. Pain remained the most often reported reason to start sedation, whereas exhaustion as a reason for sedation increased. The use of benzodiazepines increased from 69.9% to 90.4%. In the first and second measurements, symptom-directed treatment during sedation was applied in 56% to 58% of the cases. In the second period, there was more often an explicit decision to not give artificial hydration during sedation (78.8% vs 56.3%). Of the physicians, 34.2% were convinced that sedation shortened the life of the patient because of dehydration. CONCLUSIONS After the introduction of the guideline, physicians reported that changes in palliative sedation practice conform to the recommendations of this guideline. For example, benzodiazepines were used for sedation more frequently than before and patient involvement in the decision-making process improved. Possible effects of dehydration and the large variation in symptom-directed treatment during sedation deserve careful attention.

Extradural ropivacaine and bupivacaine in hip surgery

We studied 126 patients undergoing elective hip surgery; they received 20 ml of 0.5%, 0.75%, 1.0% ropivacaine or 0.5% bupivacaine extradurally in a double-blind design. Sensory block (pinprick), motor block (modified Bromage scale), quality of analgesia and neuromuscular block were assessed intermittently. Heart rate and arterial pressure were measured at regular intervals. A total of 115 patients were evaluated for efficacy. Onset of analgesia, onset of motor block and maximum cephalad spread (T4) did not differ between the groups. Duration and quality of analgesia and motor block increased with the concentration of ropivacaine. Ropivacaine 1.0% provided a longer duration of analgesia and motor block, more intense motor block and more patients with satisfactory analgesia than 0.5% bupivacaine. More patients treated with the higher concentrations of ropivacaine required treatment for hypotension and bradycardia.

21. Phantom pain.

Abstract:  Phantom pain is pain caused by elimination or interruption of sensory nerve impulses by destroying or injuring the sensory nerve fibers after amputation or deafferentation. The reported incidence of phantom limb pain after trauma, injury or peripheral vascular diseases is 60% to 80%. Over half the patients with phantom pain have stump pain as well. Phantom pain can also occur in other parts of the body; it has been described after mastectomies and enucleation of the eye.

High thoracic epidural sufentanil with bupivacaine: continuous infusion of high volume versus low volume

The purpose of the study was to investigate whether continuous infusion of a high volume of a sufentanil/bupivacaine mixture at a high thoracic level improves the analgesic effect of the mixture, compared with a dose-equivalent continuous low-volume infusion. In a prospective, observer-blind study, 60 patients scheduled for thoracic surgery received a thoracic epidural catheter for 3 days. The patients were randomly assigned by lot to one of two groups: a low-volume (LV) group (bupivacaine 0.75% with sufentanil 4 micrograms/mL, 1.0-1.3 mL/h), or a high-volume (HV) group (bupivacaine 0.125% with sufentanil 0.7 microgram/mL, 6-8 mL/h). On the first postoperative day significantly more patients in the LV group needed one or more epidural bolus injections because they experienced pain at rest (P < 0.05). On the second and third postoperative days there were no differences in bolus injections. Significantly more patients in the HV group did not require an extra epidural bolus injection (P < 0.05). There were no differences in the number of patients experiencing pain at exercise or in the incidence of side effects. A difference was found between both groups in the mean preoperative PaCO2 value (P < 0.05) and also for the PaCO2 values on Day 1 versus the preoperative values within the group (P < 0.05). On the first postoperative day the analgesic effects of a sufentanil/bupivacaine mixture at a high thoracic epidural level can be improved when injected at a continuous high-volume rate compared with a dose-equivalent continuous low-volume rate. This is true for pain at rest; for pain at exercise, there were no differences.

Cross-Cultural Adaptation to the Dutch Language of the PainDETECT-Questionnaire

Background:  The PainDETECT‐Questionnaire (PDQ) helps to identify neuropathic components in patients suffering from pain. It can be used by clinicians in daily practice and in clinical trials.

An overview of the features influencing pain after inguinal hernia repair

Pain is a prominent issue in inguinal hernia repair research as its persisting appearance is a severe complication. The interest is also urged by the combination of a high number of repairs with an estimated risk for chronic postoperative pain of 11%. Almost every healthcare provider could encounter this complication. Pain is a complex study subject, mostly defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Various explanatory factors for pain following hernia repair have been reported. Most investigators, however, discuss only a few aspects. In the present review, these factors are collected to provide a more holistic synopsis of pain following hernia repair. It may be a resource for understanding this and other postsurgical pain.

Influence of Needle Position on Lumbar Segmental Nerve Root Block Selectivity

Background and Objectives: In patients with chronic low back pain radiating to the leg, segmental nerve root blocks (SNRBs) are performed to predict surgical outcome and identify the putative symptomatic spinal nerve. Epidural spread may lead to false interpretation, affecting clinical decision making. Systematic fluoroscopic analysis of epidural local anesthetic spread and its relationship to needle tip location has not been published to date. Study aims include assessment of epidural local anesthetic spread and its relationship to needle position during fluoroscopy-assisted blocks. Methods: Patients scheduled for L4, L5, and S1 blocks were included in this prospective observational study. Under fluoroscopy and electrostimulation, they received 0.5 mL of a mixture containing lidocaine 5 mg and iohexol 75 mg. X-rays with needle tip and contrast were scored for no epidural spread (grade 0), local spread epidurally (grade 1), or to adjacent nerve roots (grade 2). Results: Sixty-five patients were analyzed for epidural spread, 62 for needle position. Grade 1 epidural spread occurred in 47% of L4 and 28% of L5 blocks and grade 2 spread in 3 blocks (5%; L5 n = 1, S1 n = 2). For lumbar blocks, the needle was most frequently found in the lateral upper half of the intervertebral foramen. Epidural spread occurred more frequently with medial needle positions (P = .06). Conclusion: The findings suggest (P = .06) that the risk of grade 1 and 2 lumbar epidural spread, which results in decreased SNRB selectivity, is greater with medial needle positions in the intervertebral foramen. The variability in anatomic position of the dorsal root ganglion necessitates electrostimulation to guide SNRB in addition to fluoroscopy.

Lumbar segmental nerve blocks with local anesthetics, pain relief, and motor function: a prospective double-blind study between lidocaine and ropivacaine.

Selective segmental nerve blocks with local anesthetics are applied for diagnostic purposes in patients with chronic back pain to determine the segmental level of the pain. We performed this study to establish myotomal motor effects after L4 spinal nerve blocks by lidocaine and ropivacaine and to evaluate the relationship with pain. Therefore, 20 patients, of which 19 finished the complete protocol, with chronic lumbosacral radicular pain without neurological deficits underwent segmental nerve blocks at L4 with both lidocaine and ropivacaine. Pain intensity scores (verbal numeric rating scale; VNRS) and the maximum voluntary muscle force (MVMF; using a dynamometer expressed in newtons) of the tibialis anterior and quadriceps femoris muscles were measured on the painful side and on the control side. The median VNRS decrease was 4.0 (P < 0.00001; Wilcoxon’s signed rank test), without significant differences between ropivacaine and lidocaine (Mann-Whitney U-test). A difference in effect on MVMF was found for affected versus control side (P = 0.016; Tukey test). Multiple regression revealed a significant negative correlation for change in VNRS score versus change in median MVMF (Spearman R = −0.48:P = 0.00001). This study demonstrates that in patients with unilateral chronic low back pain radiating to the leg, pain reduction induced by local anesthetic segmental nerve (L4) block is associated with increased quadriceps femoris and tibialis anterior MVMF, without differences for lidocaine and ropivacaine.

The impact of a standardized incident reporting system in the perioperative setting: a single center experience on 2,563 'near-misses' and adverse events

BackgroundThe reduction of perioperative harm is a major priority of in-hospital health care and the reporting of incidents and their causes is an important source of information to improve perioperative patient safety. We explored the number, nature and causes of voluntarily reported perioperative incidents in order to highlight the areas where further efforts are required to improve patient safety.MethodsData from the Hospital Incident Management System (HIMS), entered in the period from July 2009 to July 2012, were analyzed in a Dutch university hospital. Employees in the perioperatve field filled out a semi-structured digital form of the reporting system. The risk classification of the reported adverse events and ‘near misses’ was based on the estimated patient consequences and the risk of recurrence, according to national guidelines. Predefined reported incident causes were categorized as human, organizational, technical and patient related.ResultsIn total, 2,563 incidents (1,300 adverse events and 1,263 ‘near-miss’ events) were reported during 67,360 operations. Reporters were anesthesia, operating room and recovery nurses (37%), ward nurses (31%), physicians (17%), administrative personnel (5%), others (6%) and unmentioned (3%). A total of 414 (16%) adverse events had patient consequences (which affected 0,6% of all surgery patients), estimated as catastrophic in 2, very serious in 34, serious in 105, and marginally serious in 273 cases. Shortcomings in communication was the most frequent reported type of incidents. Non-compliance with Standard Operating Procedures (SOPs: instructions, regulations, protocols and guidelines) was reported with 877 (34%) of incident reports. In total, 1,194 (27%) voluntarily reported causes were SOP-related, mainly human-based (79%) and partially organization-based (21%). SOP-related incidents were not associated with more patient consequences than other voluntarily reported incidents. Furthermore ‘mistake or forgotten’ (15%) and ‘communication problems’ (11%) were frequently reported causes of incidents.ConclusionsThe analysis of voluntarily reported perioperative incidents identified an association between perioperative patient safety problems and human failure, such as SOP non-compliance, mistakes, forgetting, and shortcomings in communication. The data suggest that professionals themselves indicate that SOP compliance in combination with other human failures provide room for improvement.