A pilot study assessing the spiritual, emotional, physical/environmental, and physiological needs of mechanically ventilated surgical intensive care unit patients via eye tracking devices, head nodding, and communication boards.

BACKGROUND: Mechanically ventilated patients in the intensive care unit (ICU) are unable to communicate verbally. We sought to evaluate their needs via a communication board (CB) and a novel eye tracking device (ETD) that verbalizes selections made by gazing. METHODS: This was a pilot prospective study conducted in a tertiary care surgical ICU. Continuously mechanically ventilated adult surgical ICU patients with a Richmond Agitation-Sedation Scale score of -1 to +1, without cognitive impairment, were eligible. We asked patients four yes-or-no questions to assess basic needs regarding presence of pain, need for endotracheal suction, satisfactory room temperature, and position comfort. Patients were then asked if there was anything else that they wanted to communicate. All responses were confirmed by head nodding. RESULTS: The median accuracy of the CB (100% (IQR 100%-100%)) for basic needs communication (yes/no questions) was comparable with that of the ETD (100% (IQR 68.8%-100%); p=0.14) in the 12 enrolled patients. Notably, 83% of patients desired to communicate additional information, ranging from spiritual (eg, desire for prayer/chaplain), emotional (eg, frustration, desire for comfort), physical/environmental (eg, television), to physiological (eg, thirst/hunger) needs. DISCUSSION: The majority of patients desired to communicate something other than basic needs. Unless specifically assessed via an assistive communication device (eg, CB or ETD), some of these other needs would have been difficult to discern. LEVEL OF EVIDENCE: IV therapeutic care/management.

Isolation and characterization of alternatively spliced variants of the mouse sigma1 receptor gene, Sigmar1.

The sigma1 receptor acts as a chaperone at the endoplasmic reticulum, associates with multiple proteins in various cellular systems, and involves in a number of diseases, such as addiction, pain, cancer and psychiatric disorders. The sigma1 receptor is encoded by the single copy SIGMAR1 gene. The current study identifies five alternatively spliced variants of the mouse sigma1 receptor gene using a polymerase chain reaction cloning approach. All the splice variants are generated by exon skipping or alternative 3' or 5' splicing, producing the truncated sigma1 receptor. Similar alternative splicing has been observed in the human SIGMAR1 gene based on the molecular cloning or genome sequence prediction, suggesting conservation of alternative splicing of SIGMAR1 gene. Using quantitative polymerase chain reactions, we demonstrate differential expression of several splice variants in mouse tissues and brain regions. When expressed in HEK293 cells, all the splice variants fail to bind sigma ligands, implicating that each truncated region in these splice variants is important for ligand binding. However, co-immunoprecipitation (Co-IP) study in HEK293 cells co-transfected with tagged constructs reveals that all the splice variants maintain their ability to physically associate with a mu opioid receptor (mMOR-1), providing useful information to correlate the motifs/sequences necessary for their physical association. Furthermore, a competition Co-IP study showed that all the variants can disrupt in a dose-dependent manner the dimerization of the original sigma1 receptor with mMOR-1, suggesting a potential dominant negative function and providing significant insights into their function.

Selective potentiation of opioid analgesia by nonsteroidal anti-inflammatory drugs.

Opioids are often used in conjunction with nonsteroidal anti-inflammatory drugs (NSAIDs) in the treatment of moderate to severe pain. In this study we have examined interactions between these two classes of drugs. NSAIDs are inactive in the radiant heat tail-flick test, an assay of moderate to severe pain in which opioids are effective. In this assay, ibuprofen potentiated the analgesic actions of hydrocodone and oxycodone, shifting their ED(50) values by 2.5-fold and 4.6-fold despite its inactivity when given alone. These opioid/NSAID interactions were dependent upon both the opioid and the NSAID. Neither aspirin nor ketorolac influenced hydrocodone actions in this model and ibuprofen did not potentiate fentanyl or morphine analgesia. Together, these studies demonstrate potent interactions between selected combinations of opioids and NSAIDS and may help explain the clinical utility of combinations. However, the findings also illustrate differences between the drugs within each class.

Identification of three new alternatively spliced variants of the rat mu opioid receptor gene: dissociation of affinity and efficacy.

Mu opioid receptors mediate the pharmacological actions of morphine and morphine-like drugs, such as heroin. The mouse and human Oprm genes undergo splicing. In these present studies, we have identified and characterized three new MOR-1 splice variants from the rat Oprm gene. Using an RT-PCR approach, we isolated the new exons 7, 8 and 9 downstream of exon 3. The rat exons 7 and 9 were homologous to the mouse exons 7 and 9 while the rat exon 8 was not. Northern blot analysis with the new exon probes showed distinctive and abundant transcripts of the variants in the rat brain. Full-length cDNA clones containing the new exons, rMOR-1C1, rMOR-1C2 and rMOR-1D were obtained using an RT-PCR approach. Each contained the same exons 1, 2 and 3 as the original rMOR-1, followed by different combinations of the new exons in place of exon 4. In addition, we also isolated another new variant, rMOR-1A, which contains only exons 1, 2 and 3, and is homologous to the human variant MOR-1A previously identified. All the variants were highly mu-selective in binding studies with little difference in affinities for the mu ligands among the variants. However, functional evaluation of assessments of the variants using agonist stimulated [(35)S]GTPgammaS binding assays revealed marked differences among the variants, both in terms of potency and efficacy of the drugs. The relative efficacy of a series of mu opioids to each other varied depending upon the variant studied. Efficacy in the [(35)S]GTPgammaS assay did not correlate with either receptor binding affinity or with potency. Thus, selectivity of opioid action might be achieved by designing compounds with varying efficacies at different MOR-1 variants.