QRS-activated ventilation during general anesthesia for extracorporeal shock wave lithotripsy

High frequency ventilation has been claimed to improve the efficiency of extracorporeal shock wave lithotripsy (ESWL) by minimizing the movement of urinary stones during the procedure. A ventilatory mode, QRS-activated ventilation, was developed in which the stones remain motionless during the delivery of shock waves. As the shock wave is triggered to occur approximately 20 milliseconds after the R wave of the QRS complex, the mechanical breath was synchronized to occur approximately 150 ms later. QRS-activated ventilation is used in 16 patients undergoing ESWL under general anesthesia. Tidal volume was set at 3 ml/kg (234 +/- 36 ml; mean +/- SD) at a rate that equaled the heart rate (71 +/- 9 beats/min). The time between the R wave and the initiation of mechanical breath (T1) was 124 +/- 25 ms, time of mechanical breath itself (T2) was 431 +/- 67 ms, and time between end of T2 and next R wave (T3) was 264 +/- 84 ms. End-tidal CO2 measured by the large breath technique was 28.1 +/- 4.8 mmHg. During the clinical use of QRS-activated ventilation and during earlier studies using an EKG simulator and a test lung, the shock wave occurred invariably at end-expiration even at high heart rates.     

One-lung high-frequency ventilation in the management of traumatic tear of bronchus in a child

An 8-yr-old child suffered traumatic bilateral pneumothoraces and a ruptured right main bronchus. Surgical repair of the bronchus was postponed for 18 h after a definite diagnosis was established due to severe hypoxemia and hypercarbia. Only left endobronchial high-frequency ventilation with muscle relaxation corrected this pulmonary dysfunction sufficiently to enable surgical intervention.     

Renal Effects of Gentamicin in Chronic Bile Duct Ligated Rats

Patients with advanced cirrhosis and rats with short-term bile duct ligation (BDL) are prone to develop nephrotoxicity from aminoglycosides. In this study, we characterized the renal response to gentamicin in rats with chronic BDL. BDL and sham-operated (SO) rats were given gentamicin (20 and 40 mg/kg/d) for 7 consecutive days, starting on the 18th postoperative day. Administration of gentamicin to SO group caused a decrease in cortical and medullary prostaglandin E₂(PGE₂) generation. However, mild reduction in creatinine clearance and an increase in fractional excretion of sodium occurred only in the BDL rats given the high gentamicin dose. This was accompanied by a reduction in cortical and medullary PGE₂ generation and a reduction in plasma nitric oxide production. In conclusion, gentamicin administration to rats with chronic BDL causes impairment of renal function. This happens only after the occurrence of simultaneous multiple insults to the renal protective mechanisms.     

Primary presacral adenocarcinoma

A rare case of a patient who presented with a presacral tumor is described. The tumor, after complete resection, was shown to be a primary adenocarcinoma. After potential sources such as gastrointestinal, pancreas, or prostate were eliminated, the diagnosis of primary presacral adenocarcinoma was made. Possible origins of this unusual tumor are discussed.     

Puerperal renal rhabdomyosarcoma: case report and review of the literature

Renal rhabdomyosarcoma is a rare malignant mesenchymal tumor with an aggressive clinical course. We describe the case of a 39-year-old woman with a large rhabdomyosarcoma of the left kidney serendipitously discovered ultrasonographically subsequent to cesarean section. To our knowledge, this is the first reported case of renal rhabdomyosarcoma during pregnancy. The importance of ultrasound examination in the differential diagnosis of gestational flank pain is discussed.     

Raman molecular imaging: a novel spectroscopic technique for diagnosis of bladder cancer in urine specimens

Background

Raman molecular imaging (RMI) is an optical technology that combines the molecular chemical analysis of Raman spectroscopy with high-definition digital microscopic visualization. This approach permits visualization of the physical architecture and molecular environment of cells in the urine. The Raman spectrum of a cell is a complex product of its chemical bonds.

Objective

In this work, we studied the possibility of using the Raman spectrum of epithelial cells in voided urine for diagnosing urothelial carcinoma (UC).

Design, setting, and participants

Raman signals were obtained from UC tissue, then from UC touch preps obtained from surgical specimens and studied using the FALCON microscope (ChemImage, Pittsburgh, PA, USA), with a ×100 collection objective and green laser illumination (532 nm). Then, urine samples were obtained from 340 patients, including 116 patients without UC, 92 patients with low-grade tumors, and 132 patients with high-grade tumors. Spectra were obtained from an average of five cells per slide.

Measurements

Raman spectroscopy of cells from bladder cancer (BCa) tissues and patients.

Results and limitations

The Raman spectra from UC tissue demonstrate a distinct peak at a 1584 cm⁻¹ wave shift not present in benign tissues. The height of this peak correlated with the tumor's grade. The signal obtained from epithelial cells correctly diagnosed BCa with sensitivity of 92% (100% of the high-grade tumors), specificity of 91%, and a positive predictive value of 94% and a negative predictive value of 88%. The signal correctly assigned a tumor's grade in 73.9% of the low-grade tumors and 98.5% of the high-grade tumors. RMI for diagnosis of BCa is limited by the need for specialized equipment and training of laboratory personnel.

Conclusions

RMI has the potential to become a powerful diagnostic tool that allows noninvasive, accurate diagnosis of UC.