A case of supercarbia following pneumoperitoneum in an infant.

A 4-month-old healthy male infant underwent left herniotomy under general anesthesia with caudal block. Carbon dioxide (CO2) pneumoperitoneum was created through the left hernial sac for inspection of the right processus vaginalis. Episodes of desaturation associated with significant reduction in chest compliance were noted intraoperatively. This was overcome by increasing the inspired oxygen concentration (FiO2). The infant failed to regain consciousness and spontaneous respiration at the end of surgery. The chest compliance deteriorated further and clinically a CO2 pneumothorax (capnothorax) was suspected. The endtidal carbon dioxide (P(E)CO2) was initially low in the immediate postoperative period. Subsequent to the readministration of sevoflurane and manual ventilation with a Jackson Rees circuit, a sudden surge in P(E)CO2 with improvement of chest compliance was observed. At that time arterial blood gas (ABG) analysis revealed a PCO2 of 17.5 kPa (134 mmHg) and pH of 6.9. The causes of severe hypercarbia and the physiological changes observed in this infant are discussed.

Paediatric one lung anaesthesia by selective bronchial intubation.

One lung anaesthesia in paediatric patients may not always be achievable by bronchial blockade or double lumen tube intubation due to inadequate experiences or facilities. We attempted to isolate right lung by selectively intubating the left bronchus with single lumen tube on a 10 kg child. Optimal surgical condition and satisfactory oxygenation achieved but complicated with severe respiratory acidosis. The possible causes for hypercapnea in this child were discussed.

Use of arsenic trioxide as an antivascular and thermosensitizing agent in solid tumors.

Arsenic trioxide, As2O3 (ATO), has been found to be an effective chemotherapeutic for acute promyelocytic leukemia but its effect on solid tumors has not been fully explored. In the present report, we describe our observation that ATO is a potent antivascular agent and that it markedly enhances the effect of hyperthermia on tumors. The tumor blood perfusion in SCK tumors of A/J mice and FSaII tumors of C3H mice was significantly suppressed for up to 24 hours after an i.p. injection of 8 mg/kg ATO. ATO was also found to be able to increase the thermosensitivity of tumor cells in vitro. As a probable consequence of these effects, ATO treatment markedly increased the tumor growth delay caused by hyperthermia at 41.5 to 42.5 degrees C. Immunohistochemical staining of tumor tissue revealed that the expression levels of several adhesion molecules and TNFalpha are noticeably increased in tumors 2 to 6 hours after systemic ATO treatment. It is concluded that ATO is potentially useful to enhance the effect of hyperthermia on tumors at a clinically relevant temperature.

Arsenic trioxide causes selective necrosis in solid murine tumors by vascular shutdown.

To investigate the antitumor action of arsenic trioxide in solid tumors, we carried out quantitative tumor perfusion studies, using locally advanced methylcholanthrene-induced fibrosarcoma grown in BALB/c mice. The tumor perfusion studies were assessed by two separate methods: 99mTc clearance and 86Rb uptake. A single administration of arsenic trioxide (10 mg/kg i.p.) produced a preferential vascular shutdown in the tumor tissue at 2 and 6 h, leading to massive necrosis in the central part of the tumor. The phenomenon was repeatable at intervals of weekly administration of the drug in the same tumor. Normal skin, muscle, and kidney were relatively unaffected by arsenic trioxide. These results suggest that the drug may be investigated as an adjunct to the standard cancer therapeutic modalities.

Cannulation of internal jugular vein in neutral head position.

An approach to cannulate right internal jugular vein in neutral head position is described for situations where head rotation and extension are contraindicated. Venous puncture was made immediately lateral to the carotid artery at the level of cricoid cartilage and directed caudad. In 40 patients studied, the right internal jugular vein of 97.5% of the patients were successfully located by the finder needle. The mean (SE) number of puncture attempts to locate the vein was 1.3 (0.1) per patient. In 72.5% (29 patients), the veins were located exactly at the predicted point after the first attempt. However the overall success rate for cannulation by the angiocath cannula was 87.5% and short term complication rate was 5.0%. We conclude this technique is a reliable, safe alternative for central venous access, especially in patients where cervical spine movement is contraindicated or restricted.

Paediatric day care anaesthesia--our first two years experience at the Paediatric Institute, Hospital Kuala Lumpur.

The first two years anaesthetic experience of paediatric day care surgery is reviewed. Four hundred and three patients underwent 447 general surgical procedures. The mean age of the patients was 5.4 years with the youngest being 5 months old. The commonest procedures performed were herniotomy, circumcision, correction of hydrocoele and orchidopexy. The overall postoperative admission rare was 2.5%. No major complications were seen. Anaesthesia for paediatric day care surgery is safe provided patients are carefully selected and evaluated, appropriate anaesthetic management instituted and proper discharge criteria adhered to.