Toshiyuki Miyake

Continuous Urine Oxygen Tension Monitoring in Patients Undergoing Cardiac Surgery

OBJECTIVESnTo evaluate the effect of cardiopulmonary bypass (CPB) on urine oxygen tension (PuO2) and to determine whether perioperative PuO2 can predict postoperative renal dysfunction in patients undergoing cardiac surgery.nnnDESIGNnProspective clinical study.nnnSETTINGnA university research laboratory, a university-affiliated hospital.nnnPARTICIPANTSnNinety-eight consecutive adult patients undergoing coronary artery bypass surgery or valvular surgery.nnnINTERVENTIONSnPuO2 was continuously measured by inserting a polarographic electrode into the urinary tube connected to a Foley catheter.nnnMEASUREMENTS AND MAIN RESULTSnPuO2 was constant before CPB and then progressively decreased after the start of CPB. It partially recovered at weaning from CPB but did not completely return to its original level until the end of surgery. Postoperative serum creatinine concentrations were significantly higher in patients whose PuO2 decreased after CPB, as compared with those whose PuO2 was constant or increased. The amplitude and the rate of recovery in PuO2 after CPB were significantly associated with peak values of postoperative serum creatinine concentrations.nnnCONCLUSIONSnThese results suggest the possibility of PuO2 detecting an early stage of renal dysfunction in cardiac surgery, although further studies will be required to substantiate it.

Latent development of cardiac tamponade heralded by a progressive fall in hepatic venous hemoglobin oxygen saturation

Sir: Hepatic venous hemoglobin oxygen saturation (ShvO2) provides information concerning hepatic oxygen balance, and we routinely monitor it during and after hepatic resection [1]. A 67-year-old male, height 170 cm, weight 56 kg, was scheduled for right lobectomy of the liver for hepatocellular carcinoma and potential invasion into the inferior vena cava. Following induction of anesthesia, fiberoptic pulmonary artery catheters (Opticath model P 7110-EH, Oximetrix, USA) were inserted via the right internal jugular vein into the left hepatic vein and the pulmonary artery to measure ShvOz and mixed venous oxygen saturation (SvO~), respectively. Accurate placement of the catheter was guided by fluoroscopy. The readings of ShvOz and SvO 2 were calibrated by oxygen saturation values measured with a Co-oximeter (OSM-3, Radiometer, Denmark). Hepatic resection led to the detection of tumor invasion into the pericardium. Median sternotomy was performed and the extended tumor was excised. After surgery, the patient entered the intensive care unit with an endotracheal tube

Femoral arterial hypotension secondary to the placement of a pediatric intraaortic balloon

did not improve the symptoms, and urinary output was reduced, we planned to use the IABP with meticulous hemodynamic monitoring by pulmonary artery catheterization and with mechanical ventilatory support by endotracheal intubation. Before the IABP catheter (Pediatric IAB 5.5 Fr 7 cc, Tokai Medical Products, Japan) was inserted through the left femoral artery by the surgical technique, the right femoral arterial, pulmonary arterial, and central venous pressures were 71/42, 36/24, and 14 mmHg, respectively. The right brachial artery pressure was 70/44 mmHg measured by a cuff. After placement of the IABP, the right femoral artery pressure acutely decreased to 50/30 mmHg while the right brachial artery pressure was 80/50mmHg. Because we suspected that the inflation of the IABP balloon was the cause of the pressure difference between the upper and the lower extremities, we stopped the driving of the device (Datascope System 90T). However, the right femoral artery pressure was still 50/ 30mmHg, whereas the right brachial artery pressure was 80/ 50mmHg. We then changed the IABP catheter to another one (Datascope Pediatric IAB, 5.5Fr 7cc) with the same driving device. However, the pressure difference was the same. We gave up on placement of the IABP because further decrease accompanied by femoral arterial hypotension was desperate in this patient. We pulled out the catheter along with recording the femoral arterial blood pressure (Fig. 1), which increased from 51/40 to 70/46mmHg. The brachial artery pressure was then 71/48mmHg. Sixteen days later, the heart failure worsened and cardiac arrest suddenly occurred, resulting in death. Femoral arterial hypotension secondary to the placement of a pediatric intraaortic balloon

The use of obtuse needles in aspirating drugs from ampules in the practice of anesthesia

To the editor: Risks of needlest ick injuries and needle stickt ransmit ted diseases in the practice of anesthesia have been reported [1,2]. Many needleless or protected-needle devices have been developed to reduce the risk of infections [3,4]. However, there has been little debate over unnecessary use of acute needles in aspirating drugs from ampules. We use acute needles for t ranscutaneous access including venipuncture or arterial catheterization during the anesthetic induct ion period. Afterwards, drugs are administered and arterial blood samples are taken, usually through the stopcocks. At the moment there are few occasions when we have to use acute needles during anesthetic management . However, we are forced to use acute needles even in aspirating drug from ampules, because obtuse needles for that purpose are not yet available. Consequent ly we are liable to prick our fingers instead of aspirating the drug. To make matters worse, such a form of injury often occurs when haste is required in preparing the drug to help our patient. To reduce this type of unpleasant risk, we have developed the sterilized obtuse needle (Fig. 1). Al though the idea is very simple, it promises a lot of benefit to us and our occupational envi ronment . We recommend to anesthesiologists extensive use of this obtuse needle. It could cost much less than acute needles if large-scale product ion was under taken by manufacturers. Fig. 1. A n obtuse needle (21 gauge and 3.0cm length) and its cap

An Effect of Unstable Hemoglobin Köln on Oximetry

Continuous pulse oximetry has been worldwidely spreaded nowadays, not only in OR but also in ICU and various wards.

A device for tracheal tube during CO2 Laser irradiation in laryngomicrosurgery

We devised that the segment of commercially available defensor II tube coming in contact with the vocal cord was concaved. We used this new tube during CO2 laser irradiation in laryngomicrosurgery. We corned to the conclusion that it was much more superior to the conventional tube in safety and resistance of the material to CO2 laser irradiation and in increase of the operation field.