Correlation between pain rating index and end-tidal sevoflurane concentration during sevoflurane anesthesia

Objective To investigate the correlation between the pain rating index (PRi), which is an index derived from processed electroencephalography signals, and the end-tidal sevoflurane concentration (ETsevo). Methods This study involved 50 adults with a body mass index of 18 to 25 kg/m2 who were undergoing elective surgery under general anesthesia. Thyrocricocentesis was performed with 2.5 mL of 2% tetracaine for endotracheal surface anesthesia, and intravenous injections of midazolam, etomidate, and rocuronium were then administered. The patients’ tracheas were intubated and their ventilatory rate was adjusted to maintain the partial pressure of end-tidal carbon dioxide at 30 to 35 mmHg. Anesthesia was maintained with sevoflurane. The ETsevo was adjusted to maintain anesthesia at 0.6, 0.8, 1.0, and 1.2 minimum alveolar concentration for 15 minutes each, and the PRi, mean arterial pressure (MAP), and heart rate were recorded at each concentration. Results A negative correlation was found between the PRi and ETsevo (−0.882) and between the MAP and ETsevo (−0.571). A low positive correlation was found between the PRi and MAP (0.484). Conclusions The PRi showed a high negative correlation with the ETsevo. Therefore, the PRi can be used to guide the depth regulation of sevoflurane anesthesia. Clinical trial registration number: ChiCTR-IPR-17012092

Complete resolution of postherpetic neuralgia following pallidotomy: case report

The authors report on a female patient with left-dominant Parkinson’s disease with motor fluctuations and levodopa-induced dyskinesias and comorbid postherpetic neuralgia (PHN), who underwent a right-sided pallidotomy. Besides a substantial improvement in her Parkinson’s symptoms, she reported an immediate and complete disappearance of PHN. This neuralgia had been long-standing, pharmacologically refractory, and severe (preoperative Brief Pain Inventory [BPI] pain severity score of 8.0, BPI pain interference score of 7.3, short-form McGill Pain Questionnaire sensory pain rating index of 7 and affective pain rating index of 10, Present Pain Intensity rank value of 4, and visual analog scale score of 81 mm; all postoperative scores were 0). She continued to be pain free at 16 months postoperatively.This peculiar finding adds substantially to the largely unrecognized evidence for the role of the pallidum in pain processing, based on previous electrophysiological, metabolic, anatomical, pharmacological, and clinical observations. Therefore, the potential of the pallidum as a neurosurgical target for neuropathic pain warrants further investigation.

Characterization of painful Restless Legs Syndrome sensations in an English-speaking South African population

Background and aims Restless Legs Syndrome (RLS) is characterised by unusual sensations in the legs which can be described as painful in up to 60% of RLS patients. The purpose of this study was to characterise and examine whether the presence of pain influenced the words used to describe the sensations of RLS in an English speaking population. Methods RLS participants (n=55) were divided according to whether or not painful RLS sensations were reported upon questioning. They completed the McGill Pain Questionnaire (MPQ), the International Restless Legs Syndrome Severity Scale (IRLS) and selected descriptors from a list of previously published RLS terms. Results Thirty-five percent of the RLS patients had painful sensations. The participants with painful RLS had higher Pain Rating Index (PRI) scores [median (interquartile range) 21 (17–28) vs. 14 (7.5–21) p=0.0008] and IRLS scores [23 (17–28) vs. 18 (11.5–22.5) p=0.0175] than the participants with non-painful RLS. Patients with painful RLS symptoms selected more pain-related literature terms, chose significantly different words in eight of the MPQ subclasses (both sensory and affective) and selected more intense descriptors from certain MPQ subclasses than the non-painful RLS group. The terms that characterised painful RLS were “aching”, “painful”, “cramping” and “unbearable”. Conclusions Descriptors of RLS sensations are changed by the presence of pain, which may indicate an aetiological difference in the patients who have painful RLS. Clinically, patients complaining of cramping and painful sensations may be diagnosed with a condition that mimics RLS. Thus, it is important that the most accurate set of descriptors for RLS are used to enable recognition of RLS and optimised treatment according to the RLS phenotype. Implications The diagnosis of RLS may be improved by overcoming language and cultural barriers and obtaining differential diagnostic terms for painful conditions mimicking RLS.

Prediction of hemodynamic reactivity by electroencephalographically derived Pain Rating Index in children during general anesthesia: a prospective observational study

Background: Pain rating index (PRI) is a novel measure of nociception based on integrated electroencephalogram parameters during general anesthesia. Wavelet index (WLI) as a sedation index reflects the patient's sedation state. This study aims to evaluate the performance of PRI and WLI to predict hemodynamic reactivity after tracheal intubation and skin incision in pediatric patients. Methods: 134 children undergoing elective general or urinary surgery were analyzed. PRI, WLI, heart rate (HR), and mean blood pressure (MBP) were measured at predefined time-points during tracheal intubation and skin incision. Receiver-operating characteristic (ROC) curves were computed to evaluate the predictive performance of PRI and WLI to measure hemodynamic reactivity (increase by more than 20% of either MBP or HR) during general anesthesia. Results: In 134 patients, positive reactivity of HR and MBP was observed in 95 (70.9%) and 61 (45.5%) patients induced by endotracheal intubation and 19 (14.2%) and 24 (17.9%) patients induced by skin incision. Using either HR or MBP reactivity induced by tracheal intubation as a dichotomous variable, the areas under the curves (AUCs) [95% CI] of PRI and WLI were 0.81[0.73-0.87] and 0.58[0.49-0.67] with the best cutoff values of 62 and 49; The AUCs [95% CI] of PRI and WLI were 0.82[0.75-0.88] and 0.61[0.52-0.69] after skin incision, the best cutoff values of PRI and WLI were 60 and 46, respectively. Conclusions: PRI can predict hemodynamic reactivity with the best cutoff values of 62 and 60 after tracheal intubation and skin incision in pediatric patients during general anesthesia while WLI failed in predicting hemodynamic changes. Trial registration: Chinese Clinical Trial Register (Unique identifier: ChiCTR1800015969, Date of registration: May 3, 2018). Key words: Pain Rating Index, Wavelet index, Hemodynamic reactivity, Pediatric patients

Indução da dor pelo quimioterápico docetaxel em mulheres com câncer de mama

Resumo Objetivo Descrever a frequência, características, localização, intensidade da dor em pacientes com câncer de mama em uso do quimioterápico Docetaxel. Métodos Estudo longitudinal realizado com 17 mulheres com câncer de mama em tratamento com Docetaxel. As pacientes foram avaliadas durante três ciclos da quimioterapia quanto à dor, utilizando-se os instrumentos Questionário McGill de Dor (Br-MPQ) e Brief Pain Inventory (BPI). Utilizou-se a correlação de Spearman e o teste de Mann-Whitney. Resultados Houve aumento na média da dor em todas as variáveis do BPI. Quando comparados os valores do Pain Rating Index (PRI) total foram verificados respectivamente 0,20; 0,33 e 0,24 na primeira, segunda e terceira avaliações, sendo encontrada correlação entre a intensidade da dor e a interferência em todas as atividades do cotidiano no BPI na segunda avaliação. Conclusão Houve aumento na ocorrência da dor, comprometendo as atividades diárias de vida das mulheres participantes.

Evaluation of Somatosensory Evoked Potential and Pain Rating Index in a Patient with Spinal Cord Injury Accepted Cell Therapy

Spinal cord injury (SCI) causes a high incidence of motor and sensory dysfunctions accompanied with neuropathic pain. No effective treatment is available. Both somatosensory evoked potential (SSEP) and neuropathic pain (NPP) are transmitted via myelinated large diameter fibers of deep sensory pathways. Here we aimed to evaluate whether SSEP can consistently and objectively assess transmission of deep sensory pathways, and to examine the effects of umbilical cord mesenchymal stem cell (UCMSC) transplantation on SSEP and NPP as assessed by the pain rating index (PRI) in a patient with a 2-year history of complete cervical SCI. We demonstrate that SSEP can directly reflect physiological function of myelinated large fibers in deep sensory pathway transmission (NPP is also transmitted by the same pathway). One year after UCMSC transplantation, the SSEP parameter, PRI, and clinical presentations of NPP significantly improved. Key words: Spinal cord, neuropathic pain, somatosensory evoked potential, umbilical cord mesenchymal stem cells

Rofecoxib and tramadol do not attenuate delayed-onset muscle soreness or ischaemic pain in human volunteers

We assessed the effect of rofecoxib, a cyclo-oxygenase-2 inhibitor, and tramadol, a centrally acting analgesic, on both delayed-onset muscle soreness (DOMS) and experimentally induced ischaemic pain. We induced DOMS in 10 male and 5 female healthy volunteers by downhill running for 30 min at a 12% decline and a speed of 9 km·h–1. We also induced ischaemic pain by finger movements with an arterial tourniquet around the arm. In a randomized, double-blind crossover format, we administered rofecoxib (50 mg, daily), tramadol (50 mg, 3 times per day), and a placebo (orally for 3 days), starting immediately after exercise. A 100 mm visual analogue scale (VAS) and McGill pain questionnaire were used to describe muscle soreness and ischaemic forearm pain 24 h after the exercise. The pressure pain threshold (PPT) in the thigh and ischaemic pain tolerance in the forearm were measured before exercise and 24 and 72 h after exercise. PPT decreased 24 h after exercise, compared with pre-exercise values (ANOVA, p < 0.05), but neither drug had any significant effect on the PPT. Neither rofecoxib nor tramadol had any effect on time of ischaemia tolerated or amount of finger activity during ischaemia. The VAS and pain-rating index, for both muscle soreness and experimental ischaemic pain, were not affected significantly by either drug. Both DOMS and ischaemic pain share peripheral and central mechanisms, yet neither are attenuated by rofecoxib or tramadol.

A Comparative Study of Life-Closing Spirituality in Home Hospice Patients

This secondary analysis compared two groups of home hospice patients (expressed spirituality,N= 44, and nonexpressed spirituality,N= 53) on psychological well-being and adaptation, social support, physical function, pain, and demographic variables. Independent-samplesttests found no significant differences atp< .05 for age, psychological well-being and adaptation, social support, and physical function. Three components of the McGill-Melzack Pain Questionnaire were significantly higher for the nonexpressed spirituality group: Affective Dimension, Pain Rating Index, and Number of Words Chosen. A comparative analysis of two groups of home hospice patients supported higher pain reports as significant indicators of nonexpressed spirituality in a home hospice population.