Vefa Ozcan

Preservation of pleural integrity in patients undergoing coronary artery bypass grafting: effect on postoperative bleeding and respiratory function.

Objective —The purpose of this study was to evaluate the influence of preserved integrity of pleura on postoperative bleeding and respiratory function in patients undergoing coronary artery bypass grafting (CABG). Methods and results — Seventy-two CABG patients who received pedunculated IMA graft without opening the pleura (group of intact pleura, group IP) between July 2002 and September 2004 were matched to 72 CABG patients who received pedunculated IMA graft with opened pleura (group of opened pleura, group OP).To match the patients with IP and unique patients with OP, logistic regression was used to develop a propensity score. The C statistic for this model was 0.79. Patients with IP were matched to unique patients with OP with an identical 5-digit propensity score. If this could not be done, we proceeded to a 4-, 3-, 2-, or 1-digit match. Patients characteristics were well matched. There were no differences in preoperative and peroperative variables between the groups. The incidence of postoperative pleural effusion and thoracentesis were significantly lower in group IP than group OP (pleural effusion in 15.2 versus 30.5%; p = 0.029, thoracentesis in 5.5 versus 18.5%; p = 0.036). Other pulmonary complications such as prolonged ventilation, reintubation, pneumothorax, atelectasis, diaphragmatic paralysis were similar in both groups. Patients with IP had significantly lower blood loss (520 versus 870 ml; p < 0.001) and whole blood unit transfusion (26.3 versus 41.6%, p = 0.036). Also, intensive care unit and hospital stay were similar in both groups. Conclusions — Meticulous internal mammary artery harvesting and preservation of the pleural integrity significantly reduces postoperative bleeding and pleural effusion.

Neuraminidase produces a decrease of adherence of slime-forming Staphylococcus aureus to gelatin-impregnated polyester fiber graft fabric: an experimental study.

Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts to diminish biomaterial-related infections.

What is the association of acute renal failure, angiotensin-converting enzyme inhibitor and angiotensin II receptor blocker in a young patient?

A 13-year-old girl was admitted to the hospital with unconsciousness and oliguria. She had also suffered from vomiting and weakness for 7 days. Her medical history was remarkable for delay in motor skills and mental retardation. No other investigation was performed until 2 months previously when she visited another clinic for complaints of palpitation, fatigue and sweating. For hypertension and obesity, treatment with ramipril and losartan plus hydrochlorothiazide was started. She was confused and mildly dehydrated; blood pressure, 97/50 mmHg; pulse, 97/min. She was an overweight child with a body mass index of 28 kg/m. Serum urea nitrogen 135 mg/dL (48.18 mmol/L), creatinine 7.2 mg/dL (636.48 μmol/L) and uric acid 13.3 mg/dL (791.08 μmol/L) were high and other biochemical parameters with urinalysis were normal. Her urine output was 250 mL in the previous 24 h. All medications were stopped, and she was followed with appropriate intravenous fluid. On the fifth day, the renal function test and the urine output were normal. After recovery of renal function completely, severe hypertension occurred within several days, and the mean systolic and diastolic pressure, without significant differences between the lower and upper extremities, were 180 and 120 mmHg. All biochemical markers, electrolytes, plasma catecholamines, cortisol and thyroid hormones, serum renin activity, aldosterone, serum complements, anti-ds-DNA, ANA and vanillylmandelic acid in 24-h urine and abdominal/renal Doppler ultrasonography were normal. An echocardiography showed mild left ventricle hypertrophy without coarctation. Grade 2 hypertensive retinopathy was documented by fundoscopic examination. She was very endearing, friendly, loquacious and empathetic associated with her typical facial features (Figure 1). Question