Randomised controlled trial of analgesia for the management of acute severe pain from traumatic injury: study protocol for the paramedic analgesia comparing ketamine and morphine in trauma (PACKMaN)

BACKGROUND

Prehospital analgesia is often required after traumatic injury, currently morphine is the strongest parenteral analgesia routinely available for use by paramedics in the United Kingdom (UK) when treating patients with severe pain. This protocol describes a multi-centre, randomised, double blinded trial comparing the clinical and cost-effectiveness of ketamine and morphine for severe pain following acute traumatic injury.

METHODS

A two arm pragmatic, phase III trial working with two large NHS ambulance services, with an internal pilot. Participants will be randomised in equal numbers to either (1) morphine or (2) ketamine by IV/IO injection. We aim to recruit 446 participants over the age of 16 years old, with a self-reported pain score of 7 or above out of 10. Randomised participants will receive a maximum of 20 mg of morphine, or a maximum of 30 mg of ketamine, to manage their pain. The primary outcome will be the sum of pain intensity difference. Secondary outcomes measure the effectiveness of pain relief and overall patient experience from randomisation to arrival at hospital as well as monitoring the adverse events, resource use and cost-effectiveness outcomes.

DISCUSSION

The PACKMAN study is the first UK clinical trial addressing the clinical and cost-effectiveness of ketamine and morphine in treating acute severe pain from traumatic injury treated by NHS paramedics. The findings will inform future clinical practice and provide insights into the effectiveness of ketamine as a prehospital analgesia.

TRIAL REGISTRATION

ISRCTN, ISRCTN14124474. Registered 22 October 2020, https://www.isrctn.com/ISRCTN14124474.

Evidence that orexin-A-evoked grooming in the rat is mediated by orexin-1 (OX1) receptors, with downstream 5-HT2C receptor involvement

RATIONALE

Orexins A and B have recently been discovered and shown to be derived from preproorexin, primarily expressed in the rat hypothalamus. Orexin-A has been ascribed a number of in vivo functions in the rat after intracerebroventricular (ICV) administration, including hyperphagia, neuroendocrine modulation and, most recently, evidence for a behavioural response characterised by an increase in grooming.

OBJECTIVES

Here, we have investigated the orexin-receptor subtypes involved in the grooming response to orexin-A (3 microg, ICV) in the rat.

METHODS

Male rats, habituated to clear Perspex behavioural observation boxes, were pretreated with antagonists with mixed selectivity for OX1, OX2, 5-HT2B and 5-HT2C receptor subtypes prior to the administration of orexin-A and the intense grooming response elicited by this peptide assessed.

RESULTS

Pretreatment of rats with a mixed OX1/5-HT2B/2C receptor antagonist 1-(4-methylsulfanylphenyl)-3-quinolin-4-ylurea (SB-284422), revealed a significant, but incomplete, blockade of orexin-A-induced grooming. Despite the low potency of orexin-A at 5-HT2B and 5-HT2C receptors in vitro (pKi<5), studies were undertaken to determine whether downstream 5-HT2B or 5-HT2C receptors mediate in the grooming-elicited by orexin-A. Whilst the selective 5-HT2B receptor antagonist, SB-215505 (3 mg/kg, PO, 5-HT2B, pKi=8.58; OX1, pKB < 5.15) failed to effect orexin-A-induced grooming, the selective 5-HT2C receptor antagonist, SB-242084 (1 mg/kg, IP, 5-HT2C, pKi = 8.95; OX1, pKB < 5.1) potently antagonised the grooming response to this peptide. This suggested that the partial blockade of orexin-A-induced grooming obtained with SB-284422 might be attributable to its 5-HT2C and/or OX1 receptor blocking activity. However, complete blockade of orexin-A-induced grooming by the subsequently identified selective OX1 receptor antagonist 1-(2-methylbenzoxazol-6-yl)-3-[1,5]naphthyridin-4-yl urea hydrochloride, SB-334867-A (OX1, pKB = 7.4; OX2, pKB = 5.7), devoid of appreciable affinity for either 5-HT2B (pKi < 5.3) or 5-HT2C (pKi < 5.4) receptors, provides the first definitive evidence that a central behavioural effect of orexin-A (grooming) is mediated by OX1 receptors.

CONCLUSIONS

This data suggests that orexin-A indirectly activates 5-HT2C receptors downstream from OX1 receptors to elicit grooming in the rat. The use of SB-334867-A in vivo will enable the role of OX,1 receptors within the rat central nervous system to be further characterised.

The relationship of daily mood and stressful events to symptoms in juvenile rheumatic disease

OBJECTIVES

The purpose of this study was 3-fold: 1) to assess the feasibility of a daily diary for use with children with juvenile rheumatic disease (JRD), 2) to describe daily variation in mood, stressful events, and symptoms in children with JRD, and 3) to examine the extent to which daily mood and daily stressful events predict daily symptoms in children with JRD.

METHODS

Twelve children with JRD completed a daily booklet for 7 days. The daily booklet included measures of daily mood, daily stressful events, daily symptoms, and daily function. The children also completed a visual analog scale for pain and the Children's Depression Inventory.

RESULTS

Subjects showed good compliance with scheduled completion and return of the daily diaries. Results indicated that children with JRD showed variability in daily mood, frequency of daily stressful events, and daily symptoms across days. Multilevel fixed effects models showed that more negative daily mood and more daily stressful events significantly predicted increased reports of fatigue, stiffness, and cutting back on daily activities. Negative daily mood also correlated with increases in daily reported pain.

CONCLUSIONS

These results indicate that daily diary research is both feasible and potentially informative in children with JRD. Our data emphasize the need for further investigation into the role of daily mood and daily stressful events on disease course in JRD.

The relationship of arthritis self-efficacy to daily pain, daily mood, and daily pain coping in rheumatoid arthritis patients

There is an increasing awareness in the medical community that psychosocial variables such as beliefs in self-efficacy are important determinants of treatment outcome. However, before measures of self-efficacy are widely incorporated into clinical practice, there needs to be a better understanding of how they relate to daily pain, mood and coping. In the present study 128 rheumatoid arthritis patients completed diaries for 30 days in which they provided daily ratings of joint pain, negative and positive mood, the use of pain coping strategies, and coping efficacy. The patients then participated in an evaluation session during which measures of self-efficacy (the Arthritis Self Efficacy Scale (ASES)), demographic variables, and medical status were collected. A series of hierarchical regression analyses was conducted to determine the degree to which self-efficacy measures collected at the time of the evaluation session were related to daily diary measures collected during the 30 preceding days. The results revealed that self-efficacy was significantly related to daily ratings of pain, mood, coping and coping efficacy. Interestingly, the findings regarding self-efficacy were obtained even after taking into account the effects of important demographic and medical status variables. Taken together, these results suggest that self-efficacy ratings collected from arthritis patients at the time of an evaluation session may well be related to recent experiences of daily pain and mood, as well as the daily use and perceived effectiveness of pain coping strategies.

Changes in cognitive coping skills and social support during cognitive behavioral stress management intervention and distress outcomes in symptomatic human immunodeficiency virus (HIV)-seropositive gay men

OBJECTIVE

We have previously reported decreases in dysphoria, anxiety, and total mood disturbance in symptomatic HIV seropositive gay men after a 10-week cognitive behavioral stress management (CBSM) group intervention. This structured intervention was designed a) to increase cognitive and behavioral coping skills related to managing the distress of symptomatic HIV, and b) to increase social support among group members. Here we examine the relative contribution of changes in coping skills and social support during the intervention period to reductions in dysphoria, anxiety, and distress-related symptoms in this sample.

METHODS

Participants were randomized to a 10-week CBSM group intervention or to a wait-list control condition. Coping, social supports, and mood were measured before and after the intervention period.

RESULTS

Members of the CBSM group (N = 22) showed significant improvement in cognitive coping strategies involving positive reframing and acceptance, and in social supports involving attachment, alliances, and guidance at the end of the 10-week CBSM program compared with controls (N = 18) who showed decrements in these coping abilities and no changes in social support. Improved cognitive coping, specifically acceptance of the HIV infection, was strongly related to lower dysphoria, anxiety, and total mood disturbance in both conditions. Changes in social support and in cognitive coping skills seem to mediate the effects of the experimental condition on the changes in distress noted during the intervention.

CONCLUSIONS

These results suggest that cognitive coping and social support factors can be modified by psychosocial interventions and may be important determinants of the changes in psychological well-being and quality of life during symptomatic HIV infection that can be achieved through this form of intervention.

The leukocyte/neuron cell surface antigen OX2 binds to a ligand on macrophages

The OX2 membrane glycoprotein contains two immunoglobulin superfamily (IgSF) domains and seems likely to interact with other cell surface proteins. A soluble chimeric protein with the two IgSF domains of OX2 engineered onto domains 3 + 4 of rat CD4 antigen was expressed. To detect possible weak interactions, the chimeric protein was coupled to fluorescent covaspheres to provide a highly avid display of OX2. The OX2 covaspheres bound macrophages but not other cell types. The specificity of the interaction was demonstrated by blocking with Fab fragments of the OX2 monoclonal antibody (mAb). A new mAb, MRC OX88, was raised against macrophages which also blocked the interaction and presumably recognizes the ligand. The epitope for the MRC OX2 mAb and a site for ligand binding were mapped to domain 1 by site-directed mutagenesis. The OX2 antigen is present on thymocytes, some lymphocytes, neurons and endothelial cells; thus, it has the potential to mediate interactions between these cell types and macrophages.

Cognitive-behavioral stress management decreases dysphoric mood and herpes simplex virus-type 2 antibody titers in symptomatic HIV-seropositive gay men

This study tested the effects of a 10-week group cognitive-behavioral stress management (CBSM) intervention on mood and immunologic parameters in HIV-seropositive gay men whose disease had progressed to a symptomatic stage. Men were randomized to either CBSM or a modified waiting-list control group. The CBSM intervention significantly decreased self-reported dysphoria, anxiety, and total distress. Individuals who practiced relaxation more consistently had significantly greater drops in dysphoria. The intervention also decreased herpes simplex virus-Type 2 (HSV-2) immunoglobulin G antibody titers. The control group showed no significant changes in either mood or antibody titers. Individual difference analyses revealed that decreases in dysphoria significantly predicted lower HSV-2 antibody titers by the end of the 10-week period. Neither group displayed changes in HSV-Type 1 antibody titers or in CD4+ or CD8+ cell numbers.

Pain coping strategies and coping efficacy in rheumatoid arthritis: a daily process analysis

Data from daily diaries were used to analyze pain coping processes in rheumatoid arthritis patients. For 30 consecutive days, 53 individuals described the pain coping strategies they used that day and rated the efficacy of their coping, joint pain, and positive and negative mood. Relations among variables were examined across-persons and within-persons over time. At the across-persons level of analysis, (i) daily coping efficacy was unrelated to pain coping or pain intensity, and (ii) the more frequent daily use of a wide variety of pain coping strategies was correlated with greater pain. Within-person analyses provided unique information about the relations among coping, pain, and mood not apparent in the across-persons results. Specifically, these analyses showed that increases in daily coping efficacy were not only related to decreases in pain, but also to decreases in negative mood and increases in positive mood. Time-lagged effects of coping and coping efficacy were also found. Individuals who reported high levels of coping efficacy on one day had lower levels of pain on the subsequent day. The daily use of pain reduction efforts and relaxation strategies also contributed to an improvement in next-day pain and an enhancement of positive mood. The implications of these findings for the assessment of pain and coping in rheumatoid arthritis patients are discussed.

Preservation of spatial organization and antigenicity of leukocyte surface molecules by aldehyde fixation: flow cytometry and high-resolution FESEM studies of CD62L, CD11b, and Thy-1

We used transmission and scanning electron microscopy in conjunction with immunogold labeling to study cell surface molecules for evidence of distribution-function relationships. Ascription of functional significance to surface distribution therefore requires preservation of cell morphology and maintenance of molecular expression and distribution through the multiple steps of cell preparation. These requirements prompted us to compare two methods for preparing leukocytes for analysis of surface molecule distribution: one method involved using low temperature to "stabilize" cell morphology and surface molecular organization through immunolabeling; the other involved fixation of the cells with dilute glutaraldehyde before their isolation and labeling. Binding of primary antibodies to several surface molecules, measured by flow cytometry, was comparable for cells prepared by the two methods. Cell morphology and molecular distributions, assessed by high-resolution field emission SEM, were likewise comparable. These results support the conclusion that cell morphologies and CAM distributions previously reported were not affected by exposure of the cells to low temperature through isolation and immunolabeling. Our additional observation that Thy-1 is expressed on both non-projecting and projecting membrane domains of mouse lymph node lymphocytes and rat thymocytes represents a third and new pattern of surface molecule distribution.

A cytologic evaluation of sputum in marijuana smokers

BACKGROUND

There is growing evidence that smoking marijuana produces pulmonary effects similar to those of smoking tobacco. Cytologic analysis of sputum is readily available to practicing physicians and may be used in evaluating the pulmonary health of marijuana smokers. This study examined the use of sputum cytologic testing in young, athletic, marijuana-only smokers.

METHODS

Sputum samples were collected from 25 marijuana-smoking members (surfers) who live in rural areas and do not smoke tobacco (mean age 27.5 years). The samples from the study group were compared with the sputum samples of 25 urban tobacco smokers and 25 nonsmokers of similar ages. Components of sputum were analyzed quantitatively and qualitatively. Subjects were educated and counseled as to the results.

RESULTS

Compared with nonsmokers, marijuana smokers showed significantly higher levels of all pathologic components (P < .05), but lower mean levels of neutrophils (5.4 vs 6.4, P = .005) and pigmented macrophages (4.9 vs 6.1, P < .001) than those of tobacco smokers. Two cases of dysplasia were noted among the tobacco smokers and one among the marijuana smokers. Test-result counseling of a limited data set (6 subjects) at 6 months resulted in a 50% self-reported cessation rate.

CONCLUSIONS

In this pilot study, results of cytologic evaluations in marijuana smokers closely resembled those observed in tobacco smokers. Further studies are needed to determine longitudinal and dose-related effects of marijuana smoking on cytologic changes. As a noninvasive testing method, sputum cytologic analysis may be a useful tool for evaluating the pulmonary health of marijuana smokers and may present an opportunity to counsel them on the benefits of cessation.