Assessment of autonomic activity in patients with rheumatic mitral stenosis

Mitral stenosis [MS] may increase sympathetic nervous activity by increasing left atrial pressure and decreasing cardiac output. Consequently, increased sympathetic nervous activity may be a risk factor for the development of clinical manifestations and complications of mitral stenosis. Thus, we aimed in this study to assess the sympathetic nervous activity in patients with rheumatic mitral stenosis using heart rate variability analysis and to define factors affecting autonomic function in those patients. The study was conducted upon thirty-one consecutive patients with rheumatic mitral stenosis in sinus rhythm attending cardiology outpatient clinics and another thirty-one normal controls matched for age and gender, and continued from April-2005 until April-2006. Heart rate variability [HRV] analysis was performed in both groups; with full clinical and echocardiographic assessment performed in mitral stenosis patients. Mean N-N interval [Mean NN], standard deviation of all N-N intervals [SDNN], number of N-N intervals that differ by more than 50 milliseconds from adjacent interval divided by the total number of all N-N intervals [PNN50], and high frequency power [HF] were lower; and low frequency power [LF] and low frequency-to-high frequency ratio [LF/HF ratio] were higher in patients with mitral stenosis as compared to their normal counterparts. HRV parameters favoring sympathetic overactivity were found to be significantly correlated to a tighter mitral valve area, higher mean trans-mitral gradient, wider left atrial diameter, higher systolic pulmonary arterial pressure, increased severity of dyspnea and overall duration of patients' symptoms. Thus, sympathetic nervous activity is increased in patients with mitral stenosis and sympathetic overactivity worsens their symptoms. Most significant factors that affect autonomic function in those patients are mitral valve area, mean transmitral gradient, left atrial diameter, and systolic pulmonary arterial pressure

Modified Scott's operation for management of lumbar spondylolysis and minimal degree spondylolithesis

Thirty-two patients complaining of low back pain and diagnosed as spondylolysis were included in this study. All of them had spondylolysis of the lumbar spine at different levels. The affected level was L5 [n = 16], L4 [n = 10] and multiple-levels lysis [n = 6]. Twenty-two patients had associated grade I spondylolithesis in association with the lysis. The other 11 patients had spondylolysis only. These patients were managed surgically in this study by the modified Scotts technique using pedicular screws and washers as anchorage point instead of wiring around the transverse process. The defect was filled by iliac grafts either paste or tricortical one. Minimal decompression through limited fenestration was done in three patients. The patients were followed up for one year at least. The follow up duration ranged between 12 and 30 months with an average 18 months. The study concluded that this modified technique is a safe and easy technique, avoiding the complications of wire breakage and transverse process fracture of the traditional Scotts technique. It can be applied to multiple level lysis with the preservation of a good back motion

Mechanical ventilation with traditional large tidal volume versus lower tidal volune in patients with acute lung injury: pulmonary and hemodynamic study

This study was carried out in the ICU of Assuit University Hospital. A total of 30 patients who fulfilled the criteria of acute lung injury [AL1] and ARDS with lung injury score of 2.5 were enrolled in the study. The patients were randomly classified into 2 groups namely traditional tidal volume group which was managed with TV of 10- 12 ml/kg, and lower tidal volume group which was managed with TV of 6 ml/kg. The patients were mechanically ventilated using SIMV mode. In the traditional group of patients, the plateau pressure was kept >/= 40 cm H2O, respiratory rate was adjusted to maintain PaCO2 of 35-45 mmHg. PEEP level was >/= 5cmH2O. in the lower tidal volume group, the PaCO2 was allowed to increase [permissive hypercarbia], unless the pH was severely affected 7.2, to allow lowering of the plateau pressure to 25-30 cmH2O. PEEP was used according to the calculation of optimal PEEP. In both groups of patients, the FiO2 was adjusted to maintain PaO2 60 mmHg, and arterial oxygen saturation >/= 90%. Traditional or protective mechanical ventilation was maintained until the patient was extubated or died. The following parameters were studied for 17 days including: hemodynamics [HR. MAP, CVP, MPAP, PCWP, and CI], arterial blood gases and oxygenation parameters [pH, PaCO2, HCO3, PaO2, PvO2, QS/QT, PaO2/Fi02]; lung mechanics [PP, PIP, CST]. The present results demonstrated that the mean value of HR was mildly decreased in the traditional tidal volume group while it was increased in the lower tidal volume group throughout all days of the study. An initial decrease in MAP, which was followed by an increase, was found in the traditional tidal e group. But lower tidal volume group demonstrated a continuous rise in MAP. Both groups of patients demonstrated an increase in CVP, MPAP and PCWP levels in most of investigated days especially in lower tidal volume group. Reasonable values of CI were observed in both groups. The mean value of PaCO2 was found to be increased in the lower tidal volume group in the early period of the study resulting in a lower PH. The greater rise in HCO3 found in later period resulting in methiogation of the increase in pH. In the conventional TV group of patients, the PH, PaCO2 and HCO3 were within its normal limits. The conventional tidal volume group revealed more elevation in PaO2 levels than lower tidal volume group in the earlier period of the study. Later on, the PaO2 levels in the lower tidal volume group were increased to greater levels than traditional tidal volume group. Similar effects were obtained concernbg PaO2/FiO2 levels in both groups. The shunt fraction was mildly improved in both studied groups especially in lower TV group, but still it did not achieve its normal levels. In both groups there was an increase in the levels of the PvO2 during most investigated days of mechanics ventilation Better respiratory mechanics were found in lower tidal volume group The plateau pressure was less, the peak inspiratory pressure was also less, and static compliance was greater in this group as compared with traditional tidal volume group. In conclusion, the consequences of application of this lung protective strategy resulted in modest effects regarding the investigated hemodynamics due to modest increments in PaCO2. Lower tidal volume group of patients demonstrated better oxygenation parameters and better improvement in lung mechanics. Further studies may be needed to investigate the combined use of other ventilatory strategies, for example: prone positioning in addition to the one applied in this work to obtain better results regarding the studied oxygenation

Protective ventilatory lung strategy and inflammatory mediators

After approval by the local ethics committee and informed consent was obtained from each patient or the patient's relatives a 24 patients who were intubated and receiving mechanical ventilation [SIMV mode] and who fulfilled the criteria of ALI and ARDS with lung injury score /= 60 mmHg and SaO[2] >/= 90%], Bronchoalveolar lavage [BAL] samples were taken at the first, fifth, tenth and seventeenth day of study. Samples were processed immediately for biochechemical studying in order to estimate the: total protein and the albumin content, Interleukin-6 [IL-6 Interleukin-8 [IL-8] and Tumor Necrosis Factor- alpha [TNF- alpha]: by an immunoenzymometric assay. The results of this study revealed that the BAL total proteins, albumin, IL-6, TNF- alpha were generally significantly lowered in the lower tidal volume group than the conventional tidal volume group of patients. Minimal rise in the IL-8 levels was found in lower tidal volume group, but this rise was statistically insignificant. On the contrary the conventional tidal volume group of patients demonstrated progressive significant increase in levels of IL-8. These laboratory findings may denote the presence of more intense inflammatory response initiated by the applied large tidal volume. Large tidal volume ventilatory strategy with its associated high airway pressure, through its effects on the healthy alveoli by over distending them, or through its effects on the inflammatory response by increasing the inflammatory process through the more stretch of the alveolar capillary membrane, it may lead to additional injury to the alveolar capillary membrane. On the contrary the lower tidal volume ventilatory stragegy may either did not add more injury to the alveolar capillary membrane, or it may gave the alveoli the adequate period for spontaneous resolution of the pathological process and so it may did not add more injurious mechanical stretch as indicated by less rise in the investigated cytokines in the bronchoalveolar lavage fluid. On the basis of these results, high priority should be given to preventing excessive lung stretch during institution of mechanical ventilation, and lower-tidal-volume strategy should be used in patients with acute lung injury and the acute respiratory distress syndrome

Arthrodesis hip using broad DCP

In this study, 34 patients were assessed. The mean age was 22 with a range from 16-36 years. All of them were not candidates for total hip replacement. In all patients, the other entire hip was normal. All of them were complaining of stiff arthritic hip for different causes. All of them were operated upon using the direct lateral approach exposing the hip joint and the iliac bone. Internal fixation was achieved using contoured broad DCP instead of the traditional cobra plate, to put the limp in the ideal position of arthrodesis. The greater trochanter was osteotomized with the preservation of abductor muscle attachment for easier THR. The plate was fixed to iliac bone with cancellous screws 6.5 mm and to the femur using cortical screws 4.5 mm. The mean operative time was 90 minutes. Each patient needed one unit of blood transfusion intraoperatively. A good bony union was reported in all patients. One patient of minimal infection was reported due to a general poor condition. A good postoperative lower limp function was reported in all patients. The pain completely disappeared after good bony union, except in one patient with minimal infection