The effect of vitamin A on the course of renal ablation nephropathy

Renal scarring due to pyelonephritis was shown to improve in rats given vitamin A. We evaluated the effect of vitamin A in a renal ablation nephropathy model. Four groups, each including 7 rats with 5/6 nephrectomy, were formed: group I (no vitamin A), group II (60 kIU vitamin A), group III (120 kIU vitamin A), and group IV (180 kIU vitamin A). Four sham-operated rats comprised the control group. After 6 weeks of 5/6 nephrectomy, the rats were sacrificed and serum creatinine, vitamin A, and β-carotene levels were determined in addition to histopathological evaluation of the remnant kidneys. The tubulointerstitial and glomerular changes were graded as ”0–3” and ”0–5” respectively, in accordance with the severity of the lesions. Tubulointerstitial score (TIS), mean glomerulosclerosis score (MGS, arithmetical mean of the sclerosis scores of 100 glomeruli), and severity of glomerulosclerosis index (SGI, ratio of the number of glomeruli with grade ≥3 sclerosis to the total number of glomeruli examined) were calculated for each rat. Serum creatinine levels were higher in the study groups than the control rats (P<0.05), but there was no significant difference between the study groups (although the levels increased as the dose of vitamin A increased). Serum vitamin A levels were significantly higher in the groups given vitamin A than the control rats and group I (P<0.05). In addition, serum vitamin A levels increased significantly in parallel to increasing doses of vitamin A (P<0.05). Serum β-carotene levels did not differ between the groups, except for group II, which had lower levels than controls (P=0.01). MGS and SGI were significantly higher in the study groups than control rats (P<0.05), but did not differ between the study groups. Study and control rats were not different with respect to TIS, but there was a difference between the control group and group III (P=0.04). Group II had the lowest MGS, SGI, and TIS scores among the study groups. When all the rats were considered together, vitamin A levels did not correlate with the MGS and SGI, but correlated positively with the TIS (r=0.391, P=0.027). β-Carotene levels also did not correlate with the MGS, SGI, and TIS. In conclusion, vitamin A administration did not significantly affect the clinical and pathological course of renal ablation nephropathy in rats. Furthermore, higher doses of vitamin A might even damage renal tissue. Received: 14 June 1999 / Revised: 2 December 1999 / Accepted: 2 December 1999     

Somatostatin and propranolol to treat small-for-size syndrome that occurred despite splenic artery ligation

We report our success with somatostatin and propranolol to treat small-for-size syndrome that occurred despite splenic artery ligation. A 48-year-old woman with cirrhosis due to autoimmune hepatitis underwent living-donor liver transplant; her graft-to-body weight ratio of the right lobe was 0.91%. After arterial reperfusion, portal pressure and flow were 24 cm H20 and 2.22 L/min (ie, 360 mL/100g graft/min), respectively. Following splenic artery ligation, the portal pressure decreased to 16 cm H20 and portal flow to 1.74 L/min (ie, 282 mL/100g graft/min). On the second postoperative day, small-for-size syndrome was diagnosed based on the marked prolongation of prothrombin time (international normalized ratio, 4.4), hyperbilirubinemia (359.1 micromol/L), rapid escalation of transaminases (alanine aminotransferase 2488 U/L, aspartate aminotransferase 1075 U/L) and very high portal flow rate (> 90 cm/sec). Oral propranolol (40 mg/day b.i.d.) and somatostatin infusion (250-microgram bolus followed by perfusion at a rate of 250 microgram/h for 5 days) were started. Prothrombin time and transaminase levels began to decrease the following day, although the bilirubin level increased to 495.9 micromol/L before returning to normal. The patient was discharged in excellent health 5 weeks after surgery. Despite reduction of portal pressure by splenic artery ligation, small-for-size syndrome may develop in patients with persistent high portal flow. To the best of our knowledge, this is the first report of the successful treatment of small-for-size syndrome by somatostatin and propranolol in the clinical setting.     

Differential adoption of laparoscopy by treatment indication

PURPOSE: The diffusion of laparoscopic renal surgery has been gradual. While surgery for benign and malignant kidney disease is usually within the urological domain, donor nephrectomy is multidisciplinary. Therefore, we compared the use of laparoscopy by procedure indication (kidney donor, and benign and malignant kidney disease) to examine potential specialty specific associations with the slow uptake of this technology. MATERIALS AND METHODS: Data on 53,461 patients undergoing nephrectomy for all indications between 1998 and 2003 were abstracted from the Nationwide Inpatient Sample using International Classification of Diseases, 9th Revision, Clinical Modification procedure and diagnostic codes. Generalized estimating equations were fitted to measure the association between laparoscopy use and the procedure indication (kidney donor, benign kidney disease and kidney cancer). RESULTS: The use of laparoscopy varied by treatment indication. In 2003, 33% of kidney donors underwent a laparoscopic approach compared to 22% and 16% of patients with benign and malignant kidney disease, respectively (p <0.0001). After adjusting for patient and hospital differences patients with benign (adjusted OR 0.71, 95% CI 0.58-0.94) and malignant (adjusted OR 0.51, 95% CI 0.35-0.74) kidney disease were significantly less likely to undergo laparoscopic nephrectomy than kidney donors. CONCLUSIONS: These data highlight that the use of laparoscopic renal surgery varies by procedure indication with slower adoption of laparoscopy for malignant or benign indications than for donor nephrectomy. This variation was not readily explained by differences in measurable patient and hospital factors. Further characterization of provider and nonclinical characteristics may provide additional insight into differences in the adoption of this technology, which appears to be a specialty specific phenomenon.     

Excursion and strain of the superficial peroneal nerve during inversion ankle sprain

BACKGROUND: Traction is presumed to be the mechanism of injury to the superficial peroneal nerve in an inversion ankle sprain, but it is not known whether the amount of strain caused by nerve traction is sufficient to cause nerve injury. We hypothesized that the superficial peroneal nerve would experience significant excursion and strain during a simulated inversion sprain, that sectioning of the anterior talofibular ligament would increase excursion and strain, and that an impact force would produce strain in a range that can structurally alter the nerve. METHODS: Differential reluctance transducers were placed in the superficial peroneal nerve in sixteen lower-extremity cadaver specimens to measure excursion and strain in situ. Static weight was applied to the foot in increments starting at 0.454 kg and ending at 4.54 kg. The anterior talofibular ligament was sectioned, and the measurements were repeated. A final impact force of 4.54 kg was applied to each specimen. Two-way repeated-measures analysis of variance was used to evaluate differences in excursion and strain. RESULTS: The mean excursion and strain of the superficial peroneal nerve increased with increases in the applied weight in both the group with the intact anterior talofibular ligament and the group in which it had been sectioned. Nerve excursion was greater in the sectioned-ligament group than in the intact-ligament group with all applied weights (p < 0.05). The mean nerve strain was greater in the sectioned-ligament group (range, 5.5% to 12.9%) than in the intact-ligament group (range, 3.0% to 11.6%) with application of the 0.454, 0.908, 1.362, and 1.816-kg weights (p < 0.05). With the ligament sectioned, the 4.54-kg impact force produced significantly higher mean nerve excursion and strain than did the 4.54-kg static weight (p < 0.05). CONCLUSIONS: The magnitude of strain with the impact force was in the lower range of values that have been shown to structurally alter peripheral nerves. The superficial peroneal nerve is at risk for traction injury during an ankle inversion sprain and is at additional risk with more severe sprains or with an insufficient anterior talofibular ligament.     

Rapid prototype patient-specific drill template for cervical pedicle screw placement.

OBJECTIVE: To assess the feasibility and accuracy of a drill template for the placement of a cervical pedicle screw in a single vertebral level. MATERIALS AND METHODS: A volumetric CT scan was performed on a cadaver cervical spine. Using computer software, a drill template with a predefined trajectory was constructed that was designed to match the posterior surface of the right side of the fifth cervical vertebra. A physical template was created from the computer model using a rapid prototyping machine. The drill template was used to guide drilling of a pilot hole, and a CT scan was performed to assess the accuracy of this hole. A 3.5-mm diameter pedicle screw was placed in the pilot hole. The spine was then dissected to separate the vertebrae and the trajectory of the screw was visually inspected. RESULTS: The feasibility of this patient-specific rapid prototyping technique was demonstrated. Imaging and visual inspection confirmed accurate placement of the pilot hole and cervical pedicle screw without cortical violation. CONCLUSIONS: The potential use of drill templates to place cervical pedicle screws is promising. Our initial methodology appears to provide an accurate technique and trajectory for pedicle screw placement in the cervical spine.     

Biomechanical analysis of screw-augmented intramedullary fixation for tibiotalocalcaneal arthrodesis

BACKGROUND: This study compared intramedullary (IM) fixation for tibiotalocalcaneal arthrodesis with and without a tibiotalocalcaneal augmentation screw. METHODS: Each specimen in six matched pairs of fresh frozen cadavers underwent tibiotalocalcaneal arthrodesis with an IM nail. One specimen from each pair also received a tibiotalocalcaneal augmentation screw. Initial and final stiffness, load to failure, and construct deformation at failure were calculated with dorsiflexion loading. Bone mineral density of each pair was determined. Statistical analysis was done using a paired Student t-test and a Pearson correlation. RESULTS: Initial and final stiffness and load to failure were significantly higher for the tibiotalocalcaneal screw augmented fixation group as compared with the specimens with no additional screw (initial stiffness, 128.0 versus 78.4 N/mm, p = 0.04; final stiffness, 230.9 versus 164.7 N/mm, p = 0.04; load to failure, 875.5 versus 660.2 N, p = 0.03). There was a significant negative correlation between bone mineral density and average construct deformation in the samples without the added tibiotalocalcaneal screw (r = -0.90, p = 0.02). CONCLUSIONS: In tibiotalocalcaneal arthrodesis with intramedullary nail fixation, a tibiotalocalcaneal augmentation screw provides more stable fixation. CLINICAL RELEVANCE: Use of an augmentation screw as described in this study may lead to lower complication rates, particularly in patients with osteopenic bone.     

Live donor liver transplantation for acute liver failure

BACKGROUND: Acute liver failure (ALF) carries a high mortality unless urgent orthotopic liver transplantation (OLT) is performed on time. Live donors are utilized to treat this irreversible condition first in pediatric cases and then in adults. Herein, we aimed to report our experience with live donors for ALF in a country of a deceased donor organ donation rate is only 1.5 per million people. METHODS: Among the 245 live donor liver transplantations (LDLT) performed from June 1999 to December 2005, 14 of them (6%) were performed for ALF in 8 pediatric and 6 adult cases. Right lobes were harvested for the adult cases whereas left lateral segments were harvested for pediatric cases, except one child transplanted with a right lobe graft. The etiology of the disease was; acute hepatitis B in four cases, hepatitis A in three cases, Wilson disease two cases, autoimmune hepatitis in two cases, and was unknown in three cases. RESULTS: Three-year graft and patient survival is 79% for these series. Five of the six adult patients and six of the eight pediatric cases survived after transplantation. There was not any donor mortality or major morbidity. CONCLUSIONS: LDLT offers a safe and effective modality of treatment for ALF for both pediatric and adult patients to overcome the problem of organ shortage especially in countries where the chance of receiving an organ from a deceased donor is low.     

Management of complicated hydatid cyst of the thorax

BACKGROUND: Complicated hydatid cyst of the thorax is important to the clinical approaches and treatment methods in hydatid disease. The aim of this study was to evaluate the problems of complicated pulmonary hydatid cyst, including choice of surgical methods, diagnostic clues and to discuss the inherent risks of medical therapy and the delay of surgical treatment in pulmonary hydatid disease. METHODS: Between 2002 and 2006, 40 operations were carried out in 37 patients whose diagnoses were complicated hydatid cyst. The surgical approach was a posterolateral thoracotomy in all patients; a phrenotomy in two patients and a thoracoabdominal approach in one patient and two-stage bilateral thoracotomy in four patients. The preferred surgical treatment procedure was cystotomy and modified capitonnage, which was carried out in 26 patients (70%). Other procedures included a cystotomy in five (14%) and decortication in six (16%) patients. Segmentectomy was carried out in 1 (3%), and wedge resection in four patients (11%). RESULTS: In 25 patients (67.5%), there were single hydatid cysts; whereas 12 patients (32.5%) had multiple cysts. Eleven patients had preoperative hydatid cyst history. Iatrogenic rupture of an intact hydatid cyst occurred in three patients. Extrathoracic involvement was apparent in 10 patients (27%). Intrathoracic but extrapulmonary involvement was apparent in six patients (16%). The morbidity ratio was 5%; there was prolonged air leak and atelectasis in one patient each. The mortality ratio was 3% (one patient). The average hospitalization duration for all patients was 5.7 days (range, 3-17 days). The mean follow up was 18.4 months with no recurrence. CONCLUSION: Complicated hydatid cyst may have different clinical manifestations and may present radiologically as a primary lung tumour. In patients with suspicious lung masses owing to endemic area, history of a hydatid cyst or contralateral or extrathoracic hydatid cyst involvement at the same time should indicate a complicated pulmonary hydatid cyst. Preoperative anthelmintic therapy must be avoided owing to the risk of perforation. Treatment of a complicated hydatid cyst differs from that of an intact hydatid cyst. Anatomic resection may be necessary owing to destroyed lung tissue secondary to suppuration from a hydatid cyst; however, parenchymal preserving surgery is preferable in an uncomplicated hydatid cyst. A modified capitonnage method is recommended for complicated hydatid cyst treatment as it has a low morbidity rate.     

Release of the transverse carpal ligament alone is associated with elevated pressure beneath the distal volar forearm fascia in a cadaver model of carpal tunnel syndrome

PURPOSE: The purpose of this study is to determine whether release of the distal volar forearm fascia (DVFF) is necessary at the time of median nerve decompression for carpal tunnel syndrome. METHODS: Five fresh-frozen cadaver specimens were mounted vertically with the hand dependent and a 2.27-kg weight suspended from the fingers. A pressure sensor wire was used to measure pressures starting just distal to the transverse carpal ligament (TCL). The wire was withdrawn proximally in 5-mm increments and into the forearm until pressure was below 10 mm Hg. An incision in the forearm was extended distally until the pressure sensor was found. The distance from this point to the distal volar wrist crease was measured. The TCL was released, keeping the DVFF intact, and the experiment was repeated. Paired t-tests determined whether there were statistically significant differences between measurements before and after TCL release. RESULTS: Average peak pressure under the intact TCL was 57.8 +/- 10.1 mm Hg. Average peak pressure under the DVFF with the TCL intact was 61.2 +/- 43.6 mm Hg. Following release of the TCL, average peak pressure beneath the TCL significantly decreased to 14.0 +/- 9.0 mm Hg, whereas average peak pressure at the intact DVFF increased to 64.8 +/- 48.7 mm Hg. Average locations where DVFF pressure became less than 10 mm Hg with an intact TCL and with released TCL were 4.30 +/- 1.8 cm and 4.00 +/- 1.8 cm proximal to the distal volar wrist crease, respectively. There was no significant difference between DVFF pressures before or after TCL release. CONCLUSIONS: In a cadaver model of carpal tunnel syndrome, release of the TCL alone is associated with persistent pressures >30 mm Hg in the region of the DVFF. Release of the TCL did not significantly change the location of the pressure drop-off under the DVFF.