Effect of peri-operative red blood cell transfusion on 30-day and 1-year mortality following coronary artery bypass surgery.

OBJECTIVE: The purpose of this study was to examine the effect of peri-operative red blood cell (RBC) transfusion on 30-day and 1-year mortality following coronary artery bypass grafting (CABG). METHODS: We retrospectively analysed 3024 consecutive patients who underwent isolated CABG between January 1999 and December 2001. Patient records were linked to the National Strategic Tracing Service, which records all mortality in the UK. Thirty-day and 1-year mortality were derived from Kaplan-Meier curves. Confounding variables were controlled for by constructing a propensity score for the probability of receiving a transfusion from core patient characteristics including the lowest recorded laboratory haemoglobin (LL Hb) from a clinical chemistry database (C statistic 0.81). The propensity score and the comparison variable (transfusion versus no transfusion) were included in a Cox proportional hazards analysis, allowing calculation of adjusted hazard ratios (HR) and Kaplan-Meier survival curves. RESULTS: Nine hundred and forty (31.1%) patients received RBC transfusion during or within 72h of surgery. Predictors of the need for transfusion were LL Hb and lower body mass index, use of cardiopulmonary bypass, female sex, number of grafts, renal dysfunction, increased age, extent of disease, and prior CABG; these factors were all included in the propensity score. After 1-year of follow-up, 122 (4.03%) deaths occurred. The crude HR for 1-year mortality in patients transfused was 3.0 (P<0.001). After adjusting for the propensity score, re-operation for bleeding, peri-operative blood loss and post-operative complications, the adjusted 30-day mortality was 1.9% in transfused patients compared to 1.1% in patients not transfused (P<0.05). The adjusted HR for 1-year mortality in patients transfused was 1.88 (P<0.01). CONCLUSIONS: Peri-operative RBC transfusion after CABG is associated with an increased risk of mortality during a 1-year follow-up period, with a large proportion of deaths occurring within 30-days.     

Empyema management: twelve years' experience since the introduction of video-assisted thoracoscopic surgery

We reviewed empyema management at our center since video-assisted thoracoscopic surgery (VATS) was introduced. Between 1991 and 2003, 58 patients (34 male, 24 female) ages 1 day to 17 years (median, 6 years) were identified. The median interval from the onset of symptoms to presentation was 7 days; 31% of patients received inpatient care at another hospital, and 24% were from northern communities, including the Arctic. Symptoms included fever (100%), cough (66%), shortness of breath (46%), chest pain (38%), and abdominal pain (17%). Most patients (96%) had pneumonia. The most common organisms were Streptococcus pneumoniae (22%), group A streptococcus (8%), and Mycobacterium tuberculosis (3%). No organisms were identified in 31% of patients. One empyema was trauma-related and one was due to complications of esophageal stricturoplasty. All patients received intravenous antibiotics (median, 17 days). Three patients had thoracentesis, 17 had chest tubes, 3 had thoracentesis and chest tubes, 26 had VATS, 6 had thoracotomy, and 3 had minithoracotomy. Median operative times were 86 minutes for VATS, 90 minutes for thoracotomy, and 75 minutes for minithoracotomy. Median total length of stay (LOS) was 15 days for VATS, 20.5 days for thoracotomy, and 21 days for minithoracotomy. The median preoperative LOS was longer for thoracotomy (10 days) than for VATS (5 days) or minithoracotomy (1 day). The median postoperative LOS was 14 days for VATS, 9.5 days for thoracotomy, and 8 days for minithoracotomy. Our experience shows that VATS is a safe and effective approach to managing children with empyema. The shorter preoperative LOS for VATS is likely due to earlier surgical referral and intervention using less invasive surgical procedures.     

Increased prevalence of gastrointestinal symptoms in patients with allergic disease

Background

Children with allergic diseases such as asthma and atopic dermatitis experience increased gastrointestinal symptoms. Further, physiological and histological abnormalities of the gastrointestinal tract in patients with allergic diseases have been reported. It is not certain whether adult patients experience increased gastrointestinal symptoms.

Methods

A retrospective, case–control study of 7235 adult (⩾20 years old) primary care patients was conducted. A general practitioner diagnosis of irritable bowel syndrome was used to serve as a marker of lower gastrointestinal symptoms. The prevalence of lower gastrointestinal symptoms was calculated in patients with asthma or allergic rhinitis and compared with that in patients with other chronic diseases (insulin‐dependent diabetes mellitus, osteoarthritis and rheumatoid arthritis) and with the remaining population.

Results

Gastrointestinal symptoms were significantly more common in patients with asthma (9.9%) as compared with patients with chronic diseases (4.9%; odds ratio (OR) 2.13, 95% confidence interval (CI) 1.39 to 2.56; p<0.002) or the remaining non‐asthmatic population (5.5%; OR 1.89, 95% CI 1.39 to 2.56; p<0.001). Gastrointestinal symptoms were also significantly more common in patients with allergic rhinitis (7.9%) as compared with patients with chronic diseases (4.9%; OR 1.66, 95% CI 1.02 to 2.7; p<0.05) and the remaining population (5.5%; OR 1.47, 95% CI 1.04 to 2.1; p<0.02). This phenomenon was independent of age, sex and inhaled asthma therapy in the case of patients with asthma.

Conclusions

Our findings support the hypothesis that lower gastrointestinal symptoms are more common in patients with allergic diseases such as asthma and allergic rhinitis.Lower gastrointestinal symptoms such as diarrhoea and abdominal pain are common in children with allergic diseases such as asthma¹ and atopic dermatitis.² Although food allergies and rare organic gastrointestinal diseases such as eosinophilic gastroenteropathy are associated with atopic disease, it is unlikely that they alone would account for such symptoms. Histological abnormalities of the gastrointestinal tract in patients with allergic airway diseases have also been reported. Small bowel biopsy specimens from patients with asthma and allergic rhinitis show features in common with the inflammatory reaction observed in the airways, with accumulation of eosinophils, T cells, mast cells, macrophages and increased expression of proallergic cytokines, such as interleukin (IL)4 and IL5.^3,4 Accumulation of eosinophils in the oesophageal mucosa has also been reported in patients with allergic rhinitis and asthma compared with controls.⁵ It is yet to be established whether these microscopic inflammatory changes influence gastrointestinal function. Interestingly, absorption studies with chromium 51‐labelled EDTA suggest a permeability defect of the gastrointestinal tract in patients with asthma.⁶We hypothesised that lower gastrointestinal symptoms would be more prevalent in patients with asthma and allergic rhinitis. We conducted a retrospective, case–control study of community‐based patients by evaluating computerised records of patients from a large primary healthcare centre in the UK. This strategy allowed us to identify large numbers of patients with asthma and allergic rhinitis through specific diagnostic codes (James Read codes). We used a general practitioner diagnosis of irritable bowel syndrome (IBS) to serve as a marker for lower gastrointestinal symptoms. IBS has no specific features, and, typically, diagnosis depends on the presence of lower gastrointestinal tract symptoms in the absence of organic bowel disorders. Although criteria‐based definitions of IBS have been developed,^7,8 it was not deemed necessary to use them strictly in this study, as we were simply using the diagnostic label to indicate the presence of lower gastrointestinal symptoms without an obvious organic cause.     

Biphasic synovial sarcoma of the posterior pharyngeal wall: a case report

Synovial sarcoma is not common in the head and neck region. Because its histopathologic features are many and varied, it is often misdiagnosed. We report a case of biphasic synovial sarcoma of the posterior pharyngeal wall, and we discuss the clinical and pathologic features of this case.     

Acute renal embolism. Forty-four cases of renal infarction in patients with atrial fibrillation

Acute renal embolus is rarely reported in the medical literature; thus, accurate data regarding presentation, laboratory tests, diagnostic techniques, and treatment are lacking. To better define this condition, we examined the medical records of all patients admitted to Kaplan Medical Center and Sheba Medical Center in central Israel from 1984 to 2002 who had a diagnosis of renal infarction and atrial fibrillation. We noted demographic, clinical, and laboratory parameters; method of diagnosis; treatment received; and patient outcome. We identified 44 cases of renal embolus: 23 females and 21 males, with an average age of 69.5 +/- 12.6 years. Thirty (68%) patients had abdominal pain, and 6 (14%) had a previous embolic event. Nine patients were being treated with warfarin on admission, 6 (66%) of whom had an international normalized ratio (INR) < 1.8. Hematuria was present in 21/39 (54%), and 41 (93%) patients had a serum lactate dehydrogenase (LDH) level > 400 U/dL. The mean LDH was 1100 +/- 985 U/dL. Diagnostic techniques included renal isotope scan, which was abnormal in 36/37 cases (97%); contrast-enhanced computed tomography (CT) scan, which was diagnostic in 12/15 cases (80%); and ultrasound, which was positive in only 3/27 cases (11%). Angiography was positive in 10/10 cases (100%). Twenty-three (61%) of 38 patients had normal renal function on follow-up. The 30-day mortality was 11.4%. Renal embolus was diagnosed mainly in patients aged more than 60 years, some of whom had a previous embolic event. Most of those receiving anticoagulant therapy had a subtherapeutic INR. Abdominal pain was common, as well as hematuria and an elevated LDH. These patients are at risk of subsequent embolic events to other organs. The most sensitive diagnostic technique in this population is a renal isotope scan, but contrast-enhanced CT scan requires further assessment.     

A humid corridor across the Sahara for the migration of early modern humans out of Africa 120,000 years ago

It is widely accepted that modern humans originated in sub-Saharan Africa approximately 150-200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant approximately 120-90 ka, northward dispersal likely occurred during a humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130-117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of-now buried-fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. These corridors would explain scattered findings at desert oases of Middle Stone Age Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. Here we present geochemical data that demonstrate that water in these fossil systems derived from the south during wet episodes in general, and penetrated all of the way to the Mediterranean during MIS 5e in particular. This proves the existence of an uninterrupted freshwater corridor across a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa.