Biomarkers of Delirium Duration and Delirium Severity in the ICU

OBJECTIVES

Both delirium duration and delirium severity are associated with adverse patient outcomes. Serum biomarkers associated with delirium duration and delirium severity in ICU patients have not been reliably identified. We conducted our study to identify peripheral biomarkers representing systemic inflammation, impaired neuroprotection, and astrocyte activation associated with delirium duration, delirium severity, and in-hospital mortality.

DESIGN

Observational study.

SETTING

Three Indianapolis hospitals.

PATIENTS

Three-hundred twenty-one critically ill delirious patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We analyzed the associations between biomarkers collected at delirium onset and delirium-/coma-free days assessed through Richmond Agitation-Sedation Scale/Confusion Assessment Method for the ICU, delirium severity assessed through Confusion Assessment Method for the ICU-7, and in-hospital mortality. After adjusting for age, gender, Acute Physiology and Chronic Health Evaluation II score, Charlson comorbidity score, sepsis diagnosis and study intervention group, interleukin-6, -8, and -10, tumor necrosis factor-α, C-reactive protein, and S-100β levels in quartile 4 were negatively associated with delirium-/coma-free days by 1 week and 30 days post enrollment. Insulin-like growth factor-1 levels in quartile 4 were not associated with delirium-/coma-free days at both time points. Interleukin-6, -8, and -10, tumor necrosis factor-α, C-reactive protein, and S-100β levels in quartile 4 were also associated with delirium severity by 1 week. At hospital discharge, interleukin-6, -8, and -10 retained the association but tumor necrosis factor-α, C-reactive protein, and S-100β lost their associations with delirium severity. Insulin-like growth factor-1 levels in quartile 4 were not associated with delirium severity at both time points. Interleukin-8 and S-100β levels in quartile 4 were also associated with higher in-hospital mortality. Interleukin-6 and -10, tumor necrosis factor-α, and insulin-like growth factor-1 were not found to be associated with in-hospital mortality.

CONCLUSIONS

Biomarkers of systemic inflammation and those for astrocyte and glial activation were associated with longer delirium duration, higher delirium severity, and in-hospital mortality. Utility of these biomarkers early in delirium onset to identify patients at a higher risk of severe and prolonged delirium, and delirium related complications during hospitalization needs to be explored in future studies.

Pharmacokinetics of Basiliximab for the Prevention of Graft-versus-Host Disease in Patients Undergoing Hematopoietic Cell Transplantation with Minimal-Intensity Cyclophosphamide and Fludarabine

STUDY OBJECTIVE

Basiliximab is an immunosuppressive monoclonal antibody used for rejection prevention following solid organ transplantation; the pharmacokinetics (PK) of basiliximab in this setting are known. Basiliximab may also be used for prophylaxis and treatment of graft-versus-host disease (GVHD) in patients undergoing allogeneic hematopoietic cell transplantation (HCT); however, the PK of basiliximab in this setting are not known. Clinical transplant providers expect variation in the volume of distribution and clearance after nonmyeloablative allogeneic transplantation (NMAT) compared with solid organ transplantation. Blood loss, organ site-specific antibody accumulation, and differences in blood product use during the two transplantation approaches may generate differences in basiliximab PK. Therefore, the objective of this study was to describe the PK of basiliximab after its addition to a minimally intense NMAT regimen, in conjunction with cyclosporine, for GVHD prophylaxis in patients with hematologic malignancies.

DESIGN

Population PK analysis of a single-center, single-arm, phase II clinical trial.

SETTING

Academic cancer research center.

PATIENTS

Fourteen adults with hematologic malignancies (acute myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, myelodysplastic syndrome, non-Hodgkin's lymphoma, Hodgkin's lymphoma, myelofibrosis, or severe aplastic anemia) and undergoing NMAT with a fully HLA-matched (10 of 10 antigen matched) related or unrelated donor.

MEASUREMENTS AND MAIN RESULTS

Basiliximab was used in conjunction with cyclosporine to deplete activated T cells in vivo as GVHD prophylaxis. We developed a novel competitive enzyme-linked immunosorbent assay (ELISA) method using recombinant interleukin-2 receptor alpha-chain (IL-2Ra) and a commercially available soluble sIL-2R ELISA kit to permit the quantification of serum basiliximab concentrations and characterization of the PK properties of the drug in this patient population. Using a nonlinear mixed effects model with NONMEM software, a one-compartment model with first-order elimination best described the PK, as covariate analysis using stepwise covariate modeling did not improve the base model.

CONCLUSION

We suggest a one-compartment population model with first-order elimination to capture the PK profile for basiliximab for this patient population.

Iron doped β-Tricalcium phosphate: Synthesis, characterization, hyperthermia effect, biocompatibility and mechanical evaluation

The ability of β-Tricalcium phosphate [β-TCP, β-Ca₃(PO₄)₂] to host iron at its structural lattice and its associated magnetic susceptibility, hyperthermia effect, biocompatibility and mechanical characteristics is investigated. The studies revealed the ability of β-Ca₃(PO₄)₂ to host 5.02mol% of Fe³⁺ at its Ca²⁺(5) site. Excess Fe³⁺ additions led to the formation of trigonal Ca₉Fe(PO₄)₇ and moreover a minor amount of CaFe₃(PO₄)₃O crystallization was also observed. A gradual increment in the iron content at β-Ca₃(PO₄)₂ results in the simultaneous effect of pronounced hyperthermia effect and mechanical stability. However, the presence of CaFe₃(PO₄)₃O contributes for the reduced hyperthermia effect and mechanical stability of iron substituted β-Ca₃(PO₄)₂. Haemolytic tests, cytotoxicity tests and ALP gene expression analysis confirmed the biocompatibility of the investigated systems.

Neutron radiation shielding properties of polymer incorporated self compacting concrete mixes

In this work, the neutron radiation shielding characteristics of a class of novel polymer-incorporated self-compacting concrete (PISCC) mixes are evaluated. Pulverized high density polyethylene (HDPE) material was used, at three different reference volumes, as a partial replacement to river sand in conventional concrete mixes. By such partial replacement of sand with polymer, additional hydrogen contents are incorporated in these concrete mixes and their effect on the neutron radiation shielding properties are studied. It has been observed from the initial set of experiments that there is a definite trend of reductions in the neutron flux and dose transmission factor values in these PISCC mixes vis-à-vis ordinary concrete mix. Also, the fact that quite similar enhanced shielding results are recorded even when reprocessed HDPE material is used in lieu of the virgin HDPE attracts further attention.

Feasibility of plasma circulating free RNA (cfRNA) microarray profiling and gene-specific prognostic associations in metastatic urothelial carcinoma (mUC) patients receiving platinum-based chemotherapy

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Background: The current study was undertaken to determine the feasibility of detection and expression profiling of cfRNA in mUC patients treated with platinum-based chemotherapy. Methods: Plasma samples were identified from consented mUC subjects treated with platinum-based therapy at the IU Simon Cancer Center (IUSCC) from 12/2008 – 8/5/2010. The primary feasibility measure was the detection of cfRNA at any quantitative level. An IUSCC urologic cancer 48-gene array was designed. After cfRNA extraction and cDNA preparation, cDNA were amplified in a specific target amplification step using gene-specific primers for the 48 genes in the array. Gene expression analysis was performed on amplified cDNA using 96.96 format DELTAgene microfluidic Dynamic Array platform (Fluidigm). CT values were calculated for each gene after normalization against expression of internal control gene, GAPDH. To identify associations between individual gene expression and OS, a Cox proportional hazards regression analysis was performed. Results: Plasma samples and OS data were available from 15 pts. Patient demographics included: median age – 70.8, M/F – 14/1, Cisplatin/Carboplatin regimen – 9/6, lymph node/visceral mets – 13/7. Median PFS/OS were 8.7 and 23.0 months respectively. cfRNA was detectable in all 15 patients (100%). Median quantitative cfRNA concentration was 2.68 ng/ml (range 1.9 – 6.3). 96.96 Dynamic Array was performed in all patients. All 48 gene probes passed QC testing and produced CT values suitable for analysis. On univariate analysis, overall survival was significantly associated with presence of visceral metastases and plasma cfRNA expression of AKT1, AKT2, BRCA1, CCND1, HPRT1, HSD3B1, PARP1, and RPA3 (all p < 0.05). Conclusions: Successful extraction of cfRNA suitable for microarray analysis from archived mUC patient plasma samples is feasible. Intriguing hypothesis generating associations between OS and cfRNA expression of genes mediating DNA repair, apoptosis, and cell-signaling pathways were observed. Demonstration of these findings in larger independent patient cohorts is warranted.

S100 calcium binding protein B as a biomarker of delirium duration in the intensive care unit - an exploratory analysis

BACKGROUND

Currently, there are no valid and reliable biomarkers to identify delirious patients predisposed to longer delirium duration. We investigated the hypothesis that elevated S100 calcium binding protein B (S100β) levels will be associated with longer delirium duration in critically ill patients.

METHODS

A prospective observational cohort study was performed in the medical, surgical, and progressive intensive care units (ICUs) of a tertiary care, university affiliated, and urban hospital. Sixty-three delirious patients were selected for the analysis, with two samples of S100β collected on days 1 and 8 of enrollment. The main outcome measure was delirium duration. Using the cutoff of <0.1 ng/mL and ≥0.1 ng/mL as normal and abnormal levels of S100β, respectively, on day 1 and day 8, four exposure groups were created: Group A, normal S100β levels on day 1 and day 8; Group B, normal S100β level on day 1 and abnormal S100β level on day 8; Group C, abnormal S100β level on day 1 and normal on day 8; and Group D, abnormal S100β levels on both day 1 and day 8.

RESULTS

Patients with abnormal levels of S100β showed a trend towards higher delirium duration (P=0.076); Group B (standard deviation) (7.0 [3.2] days), Group C (5.5 [6.3] days), and Group D (5.3 [6.0] days), compared to patients in Group A (3.5 [5.4] days).

CONCLUSION

This preliminary investigation identified a potentially novel role for S100β as a biomarker for delirium duration in critically ill patients. This finding may have important implications for refining future delirium management strategies in ICU patients.

Phase I study of everolimus (E, RAD001) and ganitumab (G, AMG 479) in patients (pts) with advanced solid tumors

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Background: Synergism between IGF and mTOR inhibitors has been documented preclinically. We conducted a phase I study to determine the safety, recommended phase II dose (RP2D), pharmacokinetics (PK), pharmacodynamics (PD), and antitumor efficacy of E with G. Methods: Eligible pts had good organ function, ECOG PS 0-1. The study had a standard “3+3” design, using E 5 or 10 mg orally daily (QD), and G 12 mg/kg IV every 2 wks (Q2W) in 28 day cycles (C); an expansion cohort was added at MTD for further efficacy analysis. E was given as single agent during C1D1-7 with PKs on C1D1 and D7, and continuously after C1D16. G was started on C1D15 with single agent PK. PKs for both drugs at steady state were performed on C3D1. PDs (blood and serial tumor biopsies) for IGF and PI3K/Akt/mTOR pathways were performed at baseline, C1D7, C3D1 and time of progression. Results: 20 ptswere enrolled to date, M/F: 8/12, median age 55 yrs (24-70); PS: 0/1= 13/7. The table summarizes dose levels and DLTs. The most common toxicities were fatigue (5), diarrhea, mucositis, dysgeusia, anemia and thrombocytopenia (4 each), and rigors (3). Grade (Gr) 3 toxicities were: mucositis (3), anemia (2), thrombocytopenia (2), and diarrhea (1). Pts received a median of 3 cycles (0-9). One pt discontinued study on C1D9 due to intracerebral bleed and 1 pt withdrew consent on C1D15. Among 18 evaluable pts, none responded and 9 pts (50%) had SD with a median duration of 20 wks (range 11-35). Prolonged clinical benefit (SD ≥ 20 wks) was noted in refractory fibrolamellar HCC, neuroendocrine, GIST and urachal cancers. PKs showed no significant interaction between E and G. Baseline IGF-1R and PTEN expression, and IGF1 levels did not affect clinical benefit. pS6 downregulation and pAkt upregulation in paired tumor biopsies occurred in all (7/7) or most (6/7) samples evaluated, and did not correlate with efficacy. IGF1 and IGFBP3 levels increased on-treatment in 80-90% of pts. Conclusions: E+G is safe and the RP2D is E 10 mg QD + G 12 mg/kg Q2W. While on target pS6 reduction occured, the IGF1-R inhibition did not affect pAkt upregulation from mTOR blockade. Clinical trial information: NCT01122199. [Table: see text]

Network analysis of the focal adhesion to invadopodia transition identifies a PI3K-PKCα invasive signaling axis

In cancer, deregulated signaling can produce an invasive cellular phenotype. We modeled the invasive transition as a theoretical switch between two cytoskeletal structures: focal adhesions and extracellular matrix-degrading invadopodia. We constructed molecular interaction networks of each structure and identified upstream regulatory hubs through computational analyses. We compared these regulatory hubs to the status of signaling components from head and neck carcinomas, which led us to analyze phosphatidylinositol 3-kinase (PI3K) and protein kinase C α (PKCα). Consistent with previous studies, PI3K activity promoted both the formation and the activity of invadopodia. We found that PI3K induction of invadopodia was increased by overexpression of SH2 (Src homology 2) domain-containing inositol 5'-phosphatase 2 (SHIP2), which converts the phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P(3)] that is produced by PI3K activity to phosphatidylinositol 3,4-bisphosphate [PI(3,4)P(2)], which is believed to promote invadopodia formation. Knockdown of PKCα had divergent effects on invadopodia formation, depending on the status of PI3K. Loss of PKCα inhibited invadopodia formation in cells with wild-type PI3K pathway status. Conversely, in cells with constitutively active PI3K (through activating PI3K mutants or lacking the endogenous opposing enzyme PTEN), PKCα knockdown increased invadopodia formation. Mechanistic studies revealed a negative feedback loop from PKCα that dampened PI3K activity and invasive behavior in cells with genetic hyperactivation of the PI3K pathway. These studies demonstrated the potential of network modeling as a discovery tool and identified PI3K and PKCα as interacting regulators of invasive behavior.

Nanoparticles of pure and substituted maghemites (gamma-M(x)Fe(2_x)O3 where M = Al, Cr, Mn, Zn and 0 < or = x < or = 1.3): a comparative study

Magnetic nanoparticles of pure and substituted iron oxides are prepared by single step autocombustion or by wet chemical methods. The nanoparticles prepared by the first process had mixed phase of hematite and maghemite whereas the later essentially gives maghemite phase. XRD patterns and TEM micrographs of the pure and substituted maghemites samples suggest about their monophasic nature and inverse spinel structure. Further, the size of the particles for the above iron oxide samples was found to be in the range of 4 to 30 nm. Saturation magnetization value for the samples was observed to be varying with the type and the amount of substitution. For example, magnetization value initially increased and then decreased for Al- and Mn-substitutions but it continuously decreased for Cr- and Zn-substitutions. Contrary to the saturation magnetization value, the Curie temperature decreased continuously with increased substitutions irrespective of the type of substitutions. Due to higher magnetization value of Mn-substituted maghemite (for x = 0.2, 78 Am2/kg), it has higher heating ability and specific absorption rate compared to Al-substituted maghemite (for x = 0.07, 70 Am2/kg) and pure maghemite (62 Am2/kg).

SHIP2 phosphoinositol phosphatase positively regulates EGFR-Akt pathway, CXCR4 expression, and cell migration in MDA-MB-231 breast cancer cells

The phosphoinositol phosphatase SHIP2 is an important regulator of energy metabolism. SHIP2 dephosphorylates phosphatidylinositol 3,4,5 trisphosphates which are critical second messengers in signaling pathways induced by various extracellular stimuli including insulin. SHIP2 also regulates cytoskeleton remodeling, cell adhesion and spreading. In addition, endogenous SHIP2 in HeLa cells regulates receptor endocytosis and ligand-induced EGFR degradation. Further, SHIP2 in MDA-MB-231 breast cancer cells regulates EGFR levels and supports in vitro cell proliferation and in vivo tumor growth and spontaneous metastasis. Here we examine the role of SHIP2 in EGF signaling in breast cancer cells using RNA interference. Our results show that suppression of SHIP2 in MDA-MB-231 breast cancer cells alters EGF and EGFR internalization. Upon SHIP2 silencing, EGF-induced Akt activation was reduced causing decreased nuclear levels of activated Akt. Cytokine receptor CXCR4, a downstream element of EGFR-Akt pathway that plays an important role in metastasis, is down-regulated upon SHIP2 knockdown. Finally, cell adhesion and EGF-induced cell migration were suppressed in SHIP2 silenced cells. These results demonstrate a positive role of SHIP2 in EGF-induced Akt activation, CXCR4 expression, and cell migration in breast cancer cells.

High expression of obesity-linked phosphatase SHIP2 in invasive breast cancer correlates with reduced disease-free survival

SH2-containing 5'-inositol phosphatase (SHIP2) is a known regulator of insulin function. Genetic knockout of SHIP2 in mice causes mild insulin hypersensitivity and prevents high-fat-diet-induced obesity. SHIP2 also regulates actin remodeling and epidermal growth factor receptor (EGFR) turnover and supports breast cancer; and metastatic growth. To determine the clinical significance of SHIP2 expression in breast cancer and its relationship to relevant oncogenic molecules, SHIP2 expression was determined immunohistochemically in 285 primary breast cancers; 140 ductal carcinomas in situ (DCIS) and 145 invasive carcinomas. Forty-five percent of the specimens showed high SHIP2 levels in cancer cells while only 15% of adjacent normal cells expressed high SHIP2 levels (p < 0.0001). In cancer cells, the risk of SHIP2 overexpression is elevated (a) in women aged < or =50 years (relative risk, RR = 4.13; 95% confidence interval, CI, 2.5-6.9) compared to women aged >50 years (RR = 2.37; 95% CI 1.6-3.5; p = 0.0003), and (b) in invasive carcinomas (RR = 3.52; 95% CI 2.3-5.5) compared with DCIS (RR = 2.22; 95% CI 1.5-3.5; p = 0.0009). Patients with higher SHIP2 levels in invasive carcinomas had significantly reduced disease-free (p = 0.0025) and overall survival periods (p = 0.0228). In invasive carcinomas, SHIP2 correlated with estrogen receptor absence (p = 0.003) and EGFR presence (p = 0.0147). In conclusion, SHIP2 is an important biomarker for breast cancer.

Phosphoinositol phosphatase SHIP2 promotes cancer development and metastasis coupled with alterations in EGF receptor turnover

Phosphoinositol phosphatases are important regulators of signaling pathways relevant to both diabetes and cancer. A 3'-phosphoinositol phosphatase, phosphatase homologous to tensin (PTEN), is both a tumor suppressor and a negative regulator of insulin action. A 5'-phosphoinositol phosphatase, SH2-containing 5'-inositol phosphatase (SHIP2), regulates insulin signaling and its genetic knockout prevents high-fat diet-induced obesity in mice. SHIP2 also regulates cytoskeleton remodeling and receptor endocytosis. This and the fact that both PTEN and SHIP2 act on the same substrate suggest a potential role for SHIP2 in cancer. Here we report that, in direct contrast to PTEN, SHIP2 protein expression is elevated in a number of breast cancer cell lines. RNA interference-mediated silencing of SHIP2 in MDA-231 cells suppresses epidermal growth factor receptor (EGFR) levels by means of enhanced receptor degradation. Furthermore, endogenous SHIP2 in MDA-231 breast cancer cells supports in vitro cell proliferation, increases cellular sensitivity to drugs targeting the EGFR and supports cancer development and metastasis in nude mice. In addition, significantly high proportions (44%; P = 0.0001) of clinical specimens of breast cancer tissues in comparison with non-cancerous breast tissues contain elevated expression of SHIP2 protein. Taken together, our results demonstrate that SHIP2 is a clinically relevant novel anticancer target that links perturbed metabolism to cancer development.

SH2-containing 5'-inositol phosphatase, SHIP2, regulates cytoskeleton organization and ligand-dependent down-regulation of the epidermal growth factor receptor

Phosphoinositide lipid second messengers are integral components of signaling pathways mediated by insulin, growth factors, and integrins. SHIP2 dephosphorylates phosphatidylinositol 3,4,5-trisphosphate generated by the activated phosphatidylinositol 3'-kinase. SHIP2 down-regulates insulin signaling and is present at higher levels in diabetes and obesity. SHIP2 associates with p130Cas and filamin, regulators of cell adhesion/migration and cytoskeleton, influencing cell adhesion/spreading. Type I collagen specifically induces Src-mediated tyrosine phosphorylation of SHIP2. To better understand SHIP2 function, we employed RNA interference (RNAi) approach to silence the expression of the endogenous SHIP2 in HeLa cells. Suppression of SHIP2 levels caused severe F-actin deformities characterized by weak cortical actin and peripheral actin spikes. SHIP2 RNAi cells displayed cell-spreading defects involving a notable absence of focal contact structures and the formation of multiple slender membrane protrusions capped by actin spikes. Furthermore, decreased SHIP2 levels altered distribution of early endocytic antigen 1 (EEA1)-positive endocytic vesicles and of vesicles containing internalized epidermal growth factor (EGF) and transferrin. EGF treatment of SHIP2 RNAi cells led to the following: enhanced EGF receptor (EGFR) degradation; increased EGFR ubiquitination; and increased association of EGFR with c-Cbl ubiquitin ligase. Taken together, these experiments demonstrate that SHIP2 functions in the maintenance and dynamic remodeling of actin structures as well as in endocytosis, having a major impact on ligand-induced EGFR internalization and degradation. Accordingly, we suggest that, in HeLa cells, SHIP2 plays a distinct role in signaling pathways mediated by integrins and growth factor receptors.

Evaluation of guidelines for the use of telemetry in the non-intensive-care setting

To determine if the American College of Cardiology (ACC) cardiac monitoring guidelines accurately stratify patients according to their risks for developing clinically significant arrhythmias in non-intensive-care settings, we conducted a prospective cohort study of 2,240 consecutive patients admitted to a non-intensive-care telemetry unit over 7 months. Sixty-one percent of patients were assigned to ACC class I (telemetry indicated in most patients), 38% to class II (telemetry indicated in some), and 1% to class III (telemetry not indicated). Arrhythmias were detected in 13.5% of the class I patients, 40.7% of the class II patients, and 12% of the class III patients (p <.001). Telemetry detected an arrhythmia resulting in transfer to an intensive care unit in 0.4% of the class I patients, 1.6% of the class II patients, and none of the class III patients (p =.006). Telemetry led to a change in management for 3.4% of the class I patients, 12.7% of the class II patients, and 4% of the class III patients (p <.001). When patients with chest pain as the reason for admission were moved from class I to class II and patients with arrhythmias as the reason for admission were moved from class II to class I, more arrhythmias and more clinically significant arrhythmias occurred in class I patients and the trends from class I to class III were more consistent with the purpose of the guidelines. These findings indicate that when the ACC guidelines are reexamined, consideration should be given to changing them so they are more useful in non-intensive-care settings.

Therapeutic preparations of normal polyspecific IgG (IVIg) induce apoptosis in human lymphocytes and monocytes: a novel mechanism of action of IVIg involving the Fas apoptotic pathway

Therapeutic preparations of normal human IgG for i.v. use (i.v.Ig) exhibit a broad spectrum of immunoregulatory activities in vitro and in vivo. I.v.Ig has been shown to inhibit the proliferation of activated B and T lymphocytes and of several autonomously growing cell lines. In this study, we demonstrate that i.v.Ig induces apoptosis in leukemic cells of lymphocyte and monocyte lineage and in CD40-activated normal tonsillar B cells, involving, at least in part, Fas (CD95/APO-1) and activation of caspases. I.v.Ig-induced apoptosis was higher in Fas-sensitive HuT78 cells than in Fas-resistant HuT78.B1 mutant cells, and soluble Fas inhibited IVIg-induced apoptosis. I.v.Ig immunoprecipitated Fas from Fas-expressing transfectants and recognized purified Fas/glutathione-S-transferase fusion proteins upon immunoblotting. Affinity-purified anti-Fas Abs from i.v.Ig induced apoptosis of CEM T cells at a 120-fold lower concentration than unfractionated i.v.Ig. Inhibitors of cysteine proteases of the caspase family, caspase 1 (IL-1beta-converting enzyme) and caspase 3 (Yama/CPP32b), partially inhibited i.v.Ig-induced apoptosis of CEM cells. Furthermore, cleavage of poly(A)DP-ribose polymerase into an 85-kDa signature death fragment was observed in CEM cells following i.v.Ig treatment. Thus, normal IgG induces apoptosis in lymphocytes and monocytes. Our results provide evidence for a role of Fas, bring new insights into the mechanisms of action of i.v.Ig in autoimmune diseases, and suggest a role of normal Ig in controlling cell death and proliferation.

Role of telemetry monitoring in the non-intensive care unit

To determine the outcomes of patients admitted to a non-intensive care telemetry unit and to assess the role of telemetry for guiding patient management decisions, data from 2,240 patients admitted to a telemetry unit were collected prospectively during 7 months. Physicians recorded the outcomes (intensive care unit transfer and mortality) and assessed whether telemetry assisted in guiding patient management. Indications for admission to the telemetry unit included chest pain syndromes (55%), arrhythmias (14%), heart failure (12%), and syncope (10%). Telemetry led to direct modifications in management in 156 patients (7%; 95% confidence interval [CI] 5.9% to 8%). Telemetry was perceived as useful but did not alter management for 127 patients (5.7%; 95% CI 4.7% to 6.6%). Two hundred forty-one patients were transferred to an intensive care unit from the telemetry unit (10.8%; 95% CI 9.5% to 12%). Nineteen patients (0.8% of all admissions; 95% CI 0.5% to 1.2%) were transferred because of an arrhythmia identified by telemetry. Routine transfer after cardiac revascularization or surgery accounted for 134 transfers; clinical deterioration accounted for 88 transfers. There were 20 deaths in the unit (0.9%; 95% CI 0.5% to 1.3%): 4 of the 20 deaths occurred while patients were being monitored. The role of telemetry in guiding patient management may be overestimated by physicians, since it detected significant arrhythmias that led to change in medications or urgent interventions in a small fraction of patients.

Outcomes of patients hospitalized to a telemetry unit

To describe the clinical course of patients admitted to a nonintensive care telemetry unit and to determine whether telemetry identifies patients at risk for transfer to the intensive care unit (ICU), 467 patients hospitalized for cardiac monitoring in a nonintensive care telemetry unit were followed until death or discharge. The American College of Cardiology guidelines for telemetry use were applied: 65% of patients were class I (monitoring definitely indicated); 33% class II (probably indicated); and 2% class III (not indicated). In 5 patients (1%), telemetry contributed to the decision for a transfer to the ICU. In 462 patients, telemetry added no significant information. Thirty-eight patients (8.1%) were transferred to an ICU: 22 because of cardiac deterioration and 16 because of noncardiac clinical deterioration. Eighteen percent of patients in class I (95% confidence interval [CI], 14.1 to 22.8), 12% in class II (95% CI, 6.7 to 17), and none in class III (95% CI, 0 to 26) were transferred to the ICU (p = 0.03). Nine patients died (1.9%), 4 with terminal illness. Three patients died while on telemetry: 1 had metastatic lung cancer and 2 died suddenly of cardiac causes during initial evaluation on the ward. Telemetry identified the terminal rhythm in the 3 patients. Patients admitted to a non-ICU monitored ward with ischemic syndromes, heart failure, and arrhythmia rarely deteriorated. Patients who did deteriorate were recognized clinically without appreciable contribution from the monitoring process. It remains unproven that heart rhythm monitoring in general practice units improves patient care.

Assessment of impaired left ventricular diastolic function in patients with coronary artery disease, using radionuclide angiography

Left ventricular (LV) diastolic filling at rest was assessed in 76 patients with coronary artery disease (CAD) and 16 healthy subjects using radionuclide angiography. Peak LV filling rate (PFR), expressed in end diastolic volume per second (EDV/sec), was subnormal in CAD patients (1.95 +/- 0.51 as compared to the normal 3.11 +/- 0.36, P < 0.001) and time to PFR (TPFR) was prolonged (171.1 +/- 79 msec versus 106.6 +/- 25 msec normal, P < 0.001). These indices were also abnormal in 60 patients with normal resting LV ejection fraction (PFR 2.17 +/- 0.48 EDV/sec, TPFR 163.9 +/- 68 msec). Abnormal LV filling at rest (PFR EDV/sec or TPFR 160 msec) was found in 88 percent of all patients with CAD, 85 percent of patients with normal resting LV ejection fraction, and 83 percent of patients without Q waves on resting electrocardiogram. Thus, LV diastolic filling, evaluated non invasively by radionuclide angiography, appears to be abnormal in a high percentage of patients with CAD independent of LV systolic function or previous myocardial infarction.

Association between cigarette smoking and coronary arterial disease in patients in India: how quantitative is it? An assessment by selective coronary arteriography

With a view to study the association between smoking and coronary arterial disease, and to identify any quantitative relationship, we undertook a cross sectional analysis of 1105 consecutive male patients investigated by selective coronary arteriography to confirm or exclude coronary arterial disease. Pattern and distribution of disease were evaluated in 3 groups of patients who never smoked; who smoked less than 5 cigarettes per day; and who smoked 6 to 60 or more cigarettes per day. Suitable statistical tests, including adjusting for confounders, were carried out. The prevalence of disease was higher amongst smokers even after adjustment for confounders. The number of cigarettes smoked, and whether the smokers had quit, made no difference to the angiographic appearance or extent of disease. There was no difference in the distribution and severity of disease amongst smokers and non-smokers. Rate ratio of disease amongst smokers in India was higher in those patients between 26 and 45 years of age than in other age groups. Smoking could be identified as a risk marker/risk factor that accelerated the disease process in those prone to develop the disease. It may be advantageous to initiate public health and preventive measures directed specifically at the group aged between 26 to 45 years, and later to address all others who smoke.

Phase analysis of radionuclide ventriculograms in patients with coronary artery disease

Phase analysis of radionuclide ventriculograms were performed in eighty patients with coronary artery disease (CAD) and in sixteen healthy subjects. The phase image in the normal group revealed a homogeneous pattern and a narrow bell shaped histogram. In forty one patients with CAD whose Left ventriculogram showed hypokinetic segments, phase image was abnormal in twenty six revealing well demarcated areas of contraction abnormality and a histogram showing broad base with multiple peaks. The mean phase angle and the standard deviation (S.D.) of phase histogram of the abnormal segments was significantly different from normal. Eighteen patients with CAD had akinetic segments. Phase analysis was abnormal in all. Six patients with CAD had dyskinetic segments. It is concluded that phase image analysis is very useful in detecting segmental wall motion abnormalities.

Labetalol and nifedipine in the management of essential hypertension

Antihypertensive effects of labetalol and nifedipine were evaluated in a double blind cross over trial in ambulatory patients with moderately severe hypertension (mean diastolic BP 101.2 +/- 1.78 mm Hg, 105 +/- 2.15 mm Hg respectively and mean systolic BP 164.2 +/- 4.2 mm Hg and 171.4 +/- 5.82 mm Hg respectively in each group of 10 patients). The effect of labetalol over the systolic and diastolic BP was highly significant (p less than 0.01). The effects of nifedipine on systolic and diastolic BP were also significant but effects on diastolic BP was highly significant (p less than 0.01). In cross over study it was seen that nifedipine was not much superior in lowering the systolic BP whereas diastolic BP was lowered to a significant level (p less than 0.05) as compared to labetalol.

Dipyridamole radionuclide ventriculography for localisation of coronary artery disease

Nineteen consecutive patients who had coronary arteriography underwent dipyridamole stress testing with 0.14 mg/kg/min infusion over 4 minutes during computer assisted radionuclide ventriculography. Global ejection fraction, diastolic function and regional ejection fraction were calculated by a semiautomatic method. There were 17 patients with severe left anterior descending disease of which 12 involved the proximal segment of the LAD, 15 patients with left circumflex disease and 13 patients with right coronary artery disease. Abnormalities in resting or stress induced regional ejection fraction was used for localisation of severe coronary artery disease. The overall sensitivity was 75 per cent with a specificity of 75 per cent, a positive predictive value of 90 per cent and a negative predictive value of 45 per cent. For LAD disease the sensitivity was 94 per cent with a 100 per cent specificity while proximal segment of LAD had a sensitivity of 100 per cent and a specificity of 57 per cent. Identification of left circumflex disease had a sensitivity of 47 per cent and a 100 per cent specificity and right coronary artery had a 85 per cent sensitivity and a 50 per cent specificity. Four patients developed ST changes, 6 developed chest discomfort and 1 patient developed giddiness. All 7 were promptly reversed with intravenous aminophylline. Thus dipyridamole radionuclide ventriculography is a highly sensitive and specific method for localisation of CAD.

Severity of mitral regurgitation in mitral valve prolapse syndrome. A Doppler echocardiographic study

Thirty-three consecutive patients with mitral valve prolapse with a systolic murmur were evaluated using pulsed doppler echocardiography to quantify the severity of mitral regurgitation. There were thirteen (39%) patients with mild regurgitation, twelve patients (36%) with moderate regurgitation and eight patients (24%) with severe regurgitation. It was noticed that, all the patients with severe regurgitation had posterior leaflet prolapse. In contrast, patients with anterior leaflet prolapse had either mild or moderate regurgitation only. Our results suggest that the degree of mitral regurgitation differs depending on the leaflet that shows the prolapse, which may be of importance in the followup of patients with mitral valve prolapse.

A study of lipid levels in Indian patients with coronary arterial disease

A detailed cross-sectional analysis of total cholesterol and triglyceride levels was studied in 1066 consecutive male patients who underwent selective coronary arteriography in our centre to confirm or exclude coronary arterial disease. There were 877 cases of coronary arterial disease and 189 patients with normal coronary arteries. Besides descriptive statistics of lipid levels in different age groups, percentile distribution was studied. Association characteristics between lipids and other risk factors was studied by multiple regression analysis. Relative risk of lipids, controlling for the confounding variable of age as well as weight was obtained using the Mantel Haenszel chi square procedure. Results revealed the occurrence of coronary artery disease with low lipid levels in our population. The 50th percentile for total cholesterol was 205 mg/dl for the cases and 186 mg/dl for controls, while for triglycerides it was 158 mg/dl for cases and 140 mg/dl for controls. Multiple regression analysis of smoking, positive family history, diabetes, hypertension, weight and age contributed a low R square value of 2.49% for cholesterol and 4.22% for triglycerides in the cases and controls. The Mantel Haenszel chi square test procedure confirmed that low lipid levels could be seen irrespective of the age or weight of individuals. It is speculated that other factors which may include ageing, metabolic or immunologic components yet to be ascertained, could contribute additionally, to atherosclerotic coronary arterial disease in our population.

Electrocardiographic left atrial enlargement--correlation with echo

To assess the utility of electrocardiogram in identifying left atrial enlargement, electrocardiogram of 600 consecutive patients were correlated with their M-mode echocardiographic findings. Left atrial enlargement, as reflected by P terminal force in V1 had sensitivity of 79%, specificity 91%, predictive value 85% and accuracy of 86%. Patients older than 30 years with large left atrium (greater than 5.0 cm) had atrial fibrillation more frequently than younger patients (P less than 0.001). It is concluded that P terminal force in V1 is a reliable indicator of left atrial enlargement.

Low dose metoprolol in acute myocardial infarction

A study of the effects of low dose Metoprolol was undertaken in 37 patients with acute myocardial infarction. These patients were randomly divided into three groups depending on the dose of the drug per kg body weight. Group I, consisting of 18 patients, received 0.36 to 0.65 mg per kg per day, Group II (10 patients) received 0.66 to 0.99 mg/kg/day, and Group III (9 patients) 1 to 1.81 mg/kg/day. To assess the degree of beta blockade achieved, the parameters that were evaluated were the fall in blood pressure and heart rate. There was a fall in systolic blood pressure which ranged from 7 to 17%, and fall in heart rate of 6.6 to 12.8% in the 3 groups over the 48-hour study period. These observations were compared with the results obtained from the Goteberg Metoprolol trial and Metoprolol in acute myocardial infarction (MIAMI) trials wherein 200 mg of Metoprolol per day were used. Our preliminary observations suggest that Indian patients may not need such a high dose, and Metoprolol at 50-100 mg per day would probably be sufficient to get the desired effect.

Systolic time intervals in dilated cardiomyopathy

Systolic Time Intervals (STI) were recorded in 45 patients with Dilated Cardiomyopathy (DCMY) to evaluate left ventricular function. Shortening of LVETI was seen in 37 (82%), prolongation of PEPI in 42 (93%), and increase in PEP/LVET ratio in 43 (95%) patients of DCMY. Global left ventricular dysfunction could be identified in all the patients (100%) with the combination of PEPI and PEP/LVET ratio. On follow up evaluation of 14 patients, change in STI status was seen to correlate with clinical status of the patients. STI as a non-invasive indicator of left ventricular function are useful in diagnosis and follow up of patients with DCMY.