Stair climbing test as a predictor of cardiopulmonary complications after pulmonary lobectomy in the elderly

BACKGROUND: The objective of this study was to assess the role of a symptom-limited stair climbing test in predicting postoperative cardiopulmonary complications in elderly candidates for lung resection. METHODS: A consecutive series of 109 patients more than 70 years of age who underwent pulmonary lobectomy for lung carcinoma from January 2000 through May 2003 formed the prospective database of this study. All patients in the analysis performed a preoperative symptom-limited stair climbing test. Univariate and multivariate analyses were performed to identify predictors of postoperative cardiopulmonary complications. RESULTS: At univariate analysis, the patients with complications had a lower forced expiratory capacity percentage of predicted (p = 0.048), predicted postoperative forced expiratory volume in 1 second percentage of predicted (p = 0.049), climbed a lower height at preoperative stair climbing test (p = 0.0004), and presented a greater proportion of cardiac comorbiditiy with respect to the patients without complications (p = 0.02). After logistic regression analysis, significant predictors of postoperative complications resulted in the presence of a concomitant cardiac disease (p = 0.04) and a low height climbed preoperatively (p = 0.0015). CONCLUSIONS: A symptom-limited stair climbing test was a safe and simple instrument capable of predicting cardiopulmonary complications in the elderly after lung resection.     

Rare detection of hepatitis B and hepatitis C virus genomes by polymerase chain reaction in seronegative donors with elevated alanine aminotransferase

BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous.     

Stair climbing test predicts cardiopulmonary complications after lung resection

STUDY OBJECTIVE: To evaluate the capability of the stair climbing test to predict cardiopulmonary complications after lung resection for lung cancer. DESIGN: A prospective cohort of candidates for lung resection. Spirometric assessment and the stair climbing test were performed the day before operation. Univariate and multivariate analyses were performed to identify predictors of postoperative complications. SETTING: Tertiary referral center. PATIENTS: A consecutive series of 160 candidates for lung resection with lung carcinoma from January 2000 through March 2001. RESULTS: At univariate analysis, the patients with complications were significantly older (p = 0.02), had a significantly lower FEV(1) percentage (p = 0.007) and predicted postoperative FEV(1) percentage (p = 0.01), had a greater incidence of a concomitant cardiac disease (p = 0.02), climbed a lower altitude at the stair climbing test (p < 0.0001), and had a lower calculated maximum oxygen consumption (O(2)max) [p = 0.03] and predicted postoperative O(2)max (p = 0.006) compared to the patients without complications. At multivariate analysis, the altitude reached at the stair climbing test remained the only significant independent predictor of complications. CONCLUSIONS: The stair climbing test is a safe and economical exercise test, and it was the best predictor of cardiopulmonary complications after lung resection.     

Hyperhomocysteinaemia and Risk of Thrombosis in Systemic Lupus Erythematosus Patients

Hyperhomocysteinaemia is strongly associated with increased relative risk of occlusive vascular disease, mainly of the carotid and coronary arteries. The aim of our study was to assess whether raised plasma homocysteine is a risk factor for thrombotic events in patients with systemic lupus erythematosus (SLE), a condition known to be associated with premature atherothrombotic complications. The study included 34 consecutive consenting SLE patients who were seen in the Rheumatology Unit of Al-Amiri hospital, one of the main teaching hospitals in Kuwait. Twenty consenting healthy subjects were included in the control group. Twenty-four patients were grouped as SLE without thrombosis and 10 had different types of thromboses. Vitamin B₁₂, folate, anticardiolipin antibodies (IgG and IgM), activated partial thromboplastin time (APTT) and total homocysteine level were measured for both patients and controls. A raised homocysteine concentration was defined as plasma homocysteine level above 9.4 mmol/l. Hyperhomocysteinaemia was found in 21 (61.8%) SLE patients. Low levels of folate and vitamin B₁₂ were significantly associated with high concentrations of plasma homocysteine (r = −0.35 and −0.39, respectively, P<0.01). SLE patients with elevated homocysteine concentration have a threefold increase in odds ratio of thrombotic events after adjusting for other risk factors (male sex, shortened APTT, treatment with prednisone, low folate and vitamin B₁₂ levels). We concluded that homocysteine is an independent risk factor for thrombosis in patients with SLE and is potentially modifiable. Received: 27 December 2001 / Accepted: 14 April 2002 Correspondence and offprint requests to: Dr I. H. Al-Salem, PO Box 16434, Al-Qadeseyah 35855, Kuwait. Tel: 965 2532025; Fax: 965 2666205; E-mail: driqbalham@hotmail.com     

Role of plasminogen activator inhibitor-1 in promoting fibrin deposition in rabbits infused with ancrod or thrombin

The role of defective fibrinolysis caused by elevated activity of plasminogen activator inhibitor-1 (PAI-1) in promoting fibrin deposition in vivo has not been well established. The present study compared the efficacy of thrombin or ancrod, a venom-derived enzyme that clots fibrinogen, to induce fibrin formation in rabbits with elevated PAI-1 levels. One set of male New Zealand rabbits received intravenous endotoxin to increase endogenous PAI-1 activity followed by a 1-hour infusion of ancrod or thrombin; another set of normal rabbits received intravenous human recombinant PAI-1 (rPAI-1) during an infusion of ancrod or thrombin. Thirty minutes after the end of the infusion, renal fibrin deposition was assessed by histopathology. Animals receiving endotoxin, rPAI-1, ancrod, or thrombin alone did not develop renal thrombi. All endotoxin-treated rabbits developed fibrin deposition when infused with ancrod (n = 4) or thrombin (n = 6). Fibrin deposition occurred in 7 of 7 rabbits receiving both rPAI-1 and ancrod and in only 1 of 6 receiving rPAI-1 and thrombin (P < .01). In vitro, thrombin but not ancrod was inactivated by normal rabbit plasma and by purified antithrombin III or thrombomodulin. The data indicate that elevated levels of PAI-1 promote fibrin deposition in rabbits infused with ancrod but not with thrombin. In endotoxin-treated rabbits, fibrin deposition that occurs with thrombin infusion may be caused by decreased inhibition of procoagulant activity and not increased PAI-1 activity.     

The regulation of hemopoiesis in long-term bone marrow cultures. II. Stimulation and inhibition of stem cell proliferation

The isolation of a DNA synthesis inhibitor (NBME fraction IV) and stimulator (RBME fraction III) specific for the hemopoietic stem cell (CFU-s) from freshly isolated normal adult and regenerating murine bone marrow, respectively, has been well documented. We have utilized long- term liquid bone marrow cultures in a further analysis of the role of these factors in the regulation of CFU-s proliferation. Our results show that shortly after feeding, at a time when the cultured CFU-s are actively proliferating, high levels of the hemopoietic stem cell proliferation stimulator fraction III can be isolated from the culture medium. In contrast, the presence of essentially noncycling CFU-s found in cultures fed 8-10 days previously correlates with high levels of the hemopoietic stem cell inhibitor fraction IV. These results suggest that a certain balance between these factors determines CFU-s proliferation in the long-term cultures. In support of this, DNA synthesis in actively cycling CFU-s in the long-term cultures is inhibited for at least 3 days by the addition of excess NBME fraction IV (inhibitor). Furthermore, DNA synthesis in noncycling cultured CFU-s is stimulated for at least 5 days by the addition of RBME fraction III (stimulator).     

Association of granulocyte-macrophage colony-stimulating factor with the crystalloid granules of human eosinophils

We have previously shown that normal-density human peripheral blood eosinophils transcribe and translate mRNA for granulocyte-macrophage colony-stimulating factor (GM-CSF) and that the intracellular distribution was granular as assessed by light microscopy immunocytochemistry. The present study was conducted to confirm this apparent association between GM-CSF and the crystalloid granule using a subcellular fractionation method for human eosinophils and immunogold electron microscopy (EM). Highly purified (> 99%, by negative selection using anti-CD16 immunomagnetic microbeads) human peripheral blood eosinophils were obtained from four asthmatic subjects (not taking systemic medication), homogenized and density fractionated (5 x 10(7) cells/subject) on linear Nycodenz gradients. Twenty-four fractions were collected from each cell preparation and analyzed for marker enzyme activities as well as total protein. Dot blot analysis with specific monoclonal antibodies (MoAbs) was used to detect the eosinophil granule proteins major basic protein (MBP) and eosinophil cationic protein (ECP). An anti-CD9 MoAb was used as an eosinophil plasma membrane marker. Lactate dehydrogenase (LDH) was used as a cytosolic marker. Immunoreactivity for GM-CSF was detected by a specific enzyme-linked immunosorbent assay using a polyclonal antihuman GM-CSF antibody and confirmed by dot blot. GM-CSF coeluted with the cellular fractions containing granule markers (MBP, ECP, eosinophil peroxidase, hexosaminidase, and arylsulphatase), but not those containing cytoplasm (LDH+) or membrane (CD9+) markers. EM examination of pooled fractions associated with the peak of GM-CSF immunoreactivity confirmed that they contained crystalloid and small granules, but not plasma membrane. In addition, quantification, using immunogold labeling with an anti/GM-CSF MoAb, indicated preferential localization of gold particles over the eosinophil granule cores of intact cells. Thus, our results indicate that GM-CSF resides as a granule-associated, stored mediator in unstimulated human eosinophils.     

Aprotinin or tranexamic acid in cardiac surgery: a propensity analysis

Canadian Journal of Anesthesia/Journal canadien d'anesthésie -     

A randomized prospective comparison of oral versus intraperitoneal ofloxacin as the primary treatment of CAPD peritonitis

Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis.