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Resistance of nasotracheal tubes used in infants
622
INTERNATIONAL
creasing
concentrations
of
fat
emulsions
do
not
significantly affect the process of fibrinolysis. In over 150 Intralipid infusions no case of venous thrombosis, fever, or other complication was encountered. No evidence of ketonuria was found as a result of those infusions and, in two patients receiving 3.0 Gm. fat per Kg. body weight over a period of 70 minutes, there was no change in pH or pC0, of arterial blood.-]. CorkeTy.
ANESTHESIA
AND INHALATION THERAPY
Studies of airway resistance were carried out with commerically available nasotracheal tubes of standard length with standard endotracheal connectors and internal diameters of 2.5, 3.0, and 3.5 mm. The results indicate that airway resistance would be increased by 41 per cent with a 3.5 mm. tube, 60 per cent with a 3.0 mm. tube, and 100 per cent with the 2.5 mm. tube in the spontaneously breathing newborn. A 2.5 mm. tube has a very high resistance when compared with the infant’s airway resistance, and should be used only in conjunction with art&al ventilation.1. Downes. OF
authors recommend that intubation be carried out as gently as possible using the smallest diameter tube that provides an adequate fit, and that the duration of intubation less.--./. Dowries.
be
limited
to 7
days
or
AOHTIC PULSE CONTOUR AND CAXUJ~C OUTPUT. C. L. Graves and T. S. Underwood. Anesthesiology 29:580-584 (May-June) 1968. The aortic pressure-pulse contour and course of pressure in the thoracic aorta to calculate beat-to-beat changes in stroke heart rate, cardiac output, mean arterial
RESISTANCE OF NASOTRACHEAL TUBES USED IN INFANTS. P. Cave and G. Fletcher. Anesthesiology 29:588-596 (May-June) 1968.
COMPLXATIONS
ABSTRACTS OF PEDIATRIC !KlRCEXY
the time are used vdume, pressure,
and peripheral resistance. A 90 cm. Teflon catheter with an internal diameter of 0.5 mm. is introduced percutaneously into the radial artery, then attached to a pressure transducer and advanced into the thoracic aorta with the guidance of the pulse contour which is displayed on an oscilloscope. On-line data is provided by a digital computer which permits immediate feedback of results with digital display. The technic, compared with more conventional determinations of cardiac output by the Fick and indicator-dilution methods, correlates well under a variety of physiologic conditions. The technic has many uses in the monitoring of patients during surgery, in the recovery room, and the intensive care unit, as well as for research purposes in anesthesiology and surgery.-_]. Downes.
PROLONGED NASOTRACHEAL
INTW~ATION IN CHILDREN. T. R. Abbott. J. Anes. 40347353 (May) 1968.
Brit.
The immediate and late complications of prolonged nasotracheal intubation in 83 children are reviewed. Twenty-six of the 30 survivors were examined by laryngoscopy, and of these 9 had significant subglottic narrowing or a subglottic web. Four of 6 children intubated during the course of severe laryngotracheo-bronchitis had subglottic narrowing. By far the most frequent complication during the course of nasotracheal intnbation was partial blockage of the tube by secretions. Adequate humidification of the inspired gas and the instillation of 0.5-2.0 ml. sterile saline into the tracheal tube at 30-minute intervals would prevent blockage of the tube by secretion. All of the patients who had postextubation strider for 3 or more days developed scarring of the larynx. Subglottic complications appeared to be more frequent in patients intubated for longer than 7 days although the number of cases is too small to permit statistical analysis. The
INTEGUMENT
AND CONNECTIVE TISSUE
METHE~MOGLOBINEMIA: A COMPLICATION OF THE SILVER NITRATE TREATMENT OF BURNS. J. L. Ternberg and E. Lute. Surgery 328-330 (February) 1968. The case of a 3-year-old patient with an 82 per cent bum is presented. The patient died on the twenty-seventh hospital day. Assay of a blood specimen revealed methemoglobin to constitute 70 per cent of the hemoglobin. When a burn is treated with silver nitrate solution, a circumstance favorable to the formation of methemoglobin may exist. Nitrate is available, microorganisms capable of reducing nitrates to nitrites may be present, and the nitrite can be absorbed into the bloodstream since it is on a granulating surface. When silver nitrate burn treatment is used, should suggest cyanosis appearance of the methemoglobinemia. Treatment may be with methylene blue or discontinuation c)f the silver nitrate.-D. T. Cloud.
INTERNATIONAL
creasing
concentrations
of
fat
emulsions
do
not
significantly affect the process of fibrinolysis. In over 150 Intralipid infusions no case of venous thrombosis, fever, or other complication was encountered. No evidence of ketonuria was found as a result of those infusions and, in two patients receiving 3.0 Gm. fat per Kg. body weight over a period of 70 minutes, there was no change in pH or pC0, of arterial blood.-]. CorkeTy.
ANESTHESIA
AND INHALATION THERAPY
Studies of airway resistance were carried out with commerically available nasotracheal tubes of standard length with standard endotracheal connectors and internal diameters of 2.5, 3.0, and 3.5 mm. The results indicate that airway resistance would be increased by 41 per cent with a 3.5 mm. tube, 60 per cent with a 3.0 mm. tube, and 100 per cent with the 2.5 mm. tube in the spontaneously breathing newborn. A 2.5 mm. tube has a very high resistance when compared with the infant’s airway resistance, and should be used only in conjunction with art&al ventilation.1. Downes. OF
authors recommend that intubation be carried out as gently as possible using the smallest diameter tube that provides an adequate fit, and that the duration of intubation less.--./. Dowries.
be
limited
to 7
days
or
AOHTIC PULSE CONTOUR AND CAXUJ~C OUTPUT. C. L. Graves and T. S. Underwood. Anesthesiology 29:580-584 (May-June) 1968. The aortic pressure-pulse contour and course of pressure in the thoracic aorta to calculate beat-to-beat changes in stroke heart rate, cardiac output, mean arterial
RESISTANCE OF NASOTRACHEAL TUBES USED IN INFANTS. P. Cave and G. Fletcher. Anesthesiology 29:588-596 (May-June) 1968.
COMPLXATIONS
ABSTRACTS OF PEDIATRIC !KlRCEXY
the time are used vdume, pressure,
and peripheral resistance. A 90 cm. Teflon catheter with an internal diameter of 0.5 mm. is introduced percutaneously into the radial artery, then attached to a pressure transducer and advanced into the thoracic aorta with the guidance of the pulse contour which is displayed on an oscilloscope. On-line data is provided by a digital computer which permits immediate feedback of results with digital display. The technic, compared with more conventional determinations of cardiac output by the Fick and indicator-dilution methods, correlates well under a variety of physiologic conditions. The technic has many uses in the monitoring of patients during surgery, in the recovery room, and the intensive care unit, as well as for research purposes in anesthesiology and surgery.-_]. Downes.
PROLONGED NASOTRACHEAL
INTW~ATION IN CHILDREN. T. R. Abbott. J. Anes. 40347353 (May) 1968.
Brit.
The immediate and late complications of prolonged nasotracheal intubation in 83 children are reviewed. Twenty-six of the 30 survivors were examined by laryngoscopy, and of these 9 had significant subglottic narrowing or a subglottic web. Four of 6 children intubated during the course of severe laryngotracheo-bronchitis had subglottic narrowing. By far the most frequent complication during the course of nasotracheal intnbation was partial blockage of the tube by secretions. Adequate humidification of the inspired gas and the instillation of 0.5-2.0 ml. sterile saline into the tracheal tube at 30-minute intervals would prevent blockage of the tube by secretion. All of the patients who had postextubation strider for 3 or more days developed scarring of the larynx. Subglottic complications appeared to be more frequent in patients intubated for longer than 7 days although the number of cases is too small to permit statistical analysis. The
INTEGUMENT
AND CONNECTIVE TISSUE
METHE~MOGLOBINEMIA: A COMPLICATION OF THE SILVER NITRATE TREATMENT OF BURNS. J. L. Ternberg and E. Lute. Surgery 328-330 (February) 1968. The case of a 3-year-old patient with an 82 per cent bum is presented. The patient died on the twenty-seventh hospital day. Assay of a blood specimen revealed methemoglobin to constitute 70 per cent of the hemoglobin. When a burn is treated with silver nitrate solution, a circumstance favorable to the formation of methemoglobin may exist. Nitrate is available, microorganisms capable of reducing nitrates to nitrites may be present, and the nitrite can be absorbed into the bloodstream since it is on a granulating surface. When silver nitrate burn treatment is used, should suggest cyanosis appearance of the methemoglobinemia. Treatment may be with methylene blue or discontinuation c)f the silver nitrate.-D. T. Cloud.