Noboru Nakano

Mediastinal ultrasonography for the assessment of mediastinal lymph node metastases in lung cancer patients

Using an ultrasonic probe inserted into the mediastinum during cervical mediastinoscopy, mediastinal ultrasonography (USM) was performed on 63 patients with lung cancer. The patients with a small peripheral mass of less than 2 cm in diameter, according to the chest X-ray results, and with mediastinal lymph nodes smaller than 1 cm in their short axes as determined by computed tomography (CT), were excluded from this study. An analysis of the areas under the receiver operating characteristic curves derived from CT and USM showed that USM was superior (P=0.043) to CT in terms of the diagnosis for mediastinal lymph node metastases, when the short axis dimension of mediastinal lymph nodes was employed for the diagnosis of metastases. The reason for this is that 97% of the mediastinal lymph nodes imaged by USM were located vertically along the body axis of the patient, and hence USM imaged the true short axis of the node in many cases. Our results indicate that USM is useful for performing a safe biopsy of lymph nodes during mediastinoscopy as well as for obtaining a clear imaging of the subcarinal nodes, which are inaccessible by normal cervical mediastinoscopy.

Immediate localization using ultrasound-guided hookwire marking of peripheral lung tumors in the operating room.

A new method of marking peripheral lung tumors using an ultrasound-guided hookwire has been developed. The procedure was done for nine tumors taking 15-20 min for each method in the operating room; all of them had no complications. In eight cases (89%), the wire tips were shown to be located within the tumor itself or within 5 mm from the targets, close enough to support appropriate surgery. Ultrasound-guided hookwire marking of peripheral tumors can provide appropriate guidance and prove effective in immediately facilitating subsequent thoracoscopic resection.

Cardiac surgery in patients with end-stage renal disease. Utility of continuous ambulatory peritoneal dialysis.

OBJECTIVES The number of patients with end-stage renal disease undergoing open heart surgery continues to grow. We evaluated continuous ambulatory peritoneal dialysis and the extracorporeal ultrafiltration method during cardiopulmonary bypass in the management of these difficult patients. METHODS These 2 methods were used in 4 patients with renal failure who underwent open heart surgery between July 1997 and March 1999. Preoperative continuous ambulatory peritoneal dialysis was conducted using standard protocols. Extracorporeal ultrafiltration method was used only during cardiopulmonary bypass. Continuous ambulatory peritoneal dialysis was initiated upon arrival at the intensive care unit. Mean follow-up was 12 months. RESULTS Postoperative blood urea nitrogen and creatinine concentrations were lower than preoperative concentrations. No patients required hemodialysis. All 4 patients were discharged to their homes. No deaths occurred. CONCLUSIONS Continuous ambulatory peritoneal dialysis and extracorporeal ultrafiltration method are combined to treat patients with end-stage renal disease who require open heart surgery. This combination is simple, and does not require specialized personnel, and obviates the hemodynamic instability associated with hemodialysis.