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Recognition of infection associated with intravenous catheters
ABSTRACTS
130
GENERAL
CONSIDERATIONS
Recognition of Infection venous Catheters. Surg 62:404-4&S,
Associated
With
Intro-
R. Freeman and 8. King. Br J 1975.
Intravenous alimentation is important in the long-term management of the seriously ill infant. Many centers of pediatric surgery use peripheral veins, leaving the central vein as a last resort because of the serious risk of infection. This paper reports four cases of colonization of intravenous catheters in peripheral veins, causing symptoms of systemic illness but without leukocytosis and with no local sepsis or inflammation at the site of cannulation of the vein. The similarity to colonization of atrioventricular shunts in the treatment of hydrocephalus is referred to, and the importance of suspecting this cause of systemic illness is emphasized. Cure results when the catheter is removed, although a local abscess may then develop and require drainage.--R.B. Zachary A Direct Vasoconstrictor the
Renal
Artery.
Chamberlain.
Effect of Mannitol
S. Temes, 0.
on
L&en, and W.
Surg Gynecol Obstet
141:223
(Au-
gust), 1975.
Mannitol in appropriate concentration can directly affect the renal vessels. The direct effect of mannitol on the renal artery was studied using spiral cut strips of canine renal arteries, Spiral cut strips were equilibrated in KrebsHenseleit bicarbonate buffer at 37°C. The strips contracted when challenged with increasing doses of mannitol. The force of contraction was directly proportional to the dose of mannitol used. Vasoconstriction is a direct effect of mannitol on the renal artery in the dose range of IO-70 mg/ml. This observation may explain some of the seemingly contradictory data which have accumulated in studies using mannitol. Recently published work from the same laboratory has revealed that, depending on the dose, mannitol can produce either an increase or decrease in renal perfusion.-George Holcomb
ANESTHESIA INHALATION Malignant
Hyperthermia.
AND THERAPY C. R. Stephen. South
Med J 68:801 (July), 1975.
Over 500 cases of malignant hyperthermia have been reported with a mortality of more
than 70”;. The cause is unknown, but in susceptible patients a massive disturbance of metabolism develops which results in a tremendous production of heat. There are a few known facts about this syndrome which can help avert or abort it. First, there is a genetic component. With a history of previous occurrences in a family, sharply elevated CPK levels have been found. An abnormally high CPK level preoperatively in the absence of other possible explanations should alert one to the potential for development of this syndrome. It may also occur with a normal CPK level. There are two potential triggering mechanisms known. The first is the use of a potent inhalation anesthetic (halothane, methoxyflurane, fluroxene, cyclopropane, ethyl ether, and possibly enflurane). The second known triggering mechanism is the muscle relaxant succinylcholine. Patients of any age may develop this syndrome, the youngest reported being 3 mo of age. The best single method to determine the onset of this syndrome early is to monitor the patient’s body temperature during the induction of anesthesia. If this increases at a rate of 1°F every IO-15 min and reaches 103°F (39.4”C) one should suspect that malignant hyperthermia is developing. The patient should be cooled as rapidly as possible by applying ice to the body surface, administering cold balanced salt solutions intravenously, flooding open body cavities with cold solutions, giving ice water enemas and stomach lavage with cold fluids. Because metabolic acidosis develops rapidly and the high metabolism causes a great oxygen demand, sodium bicarbonate should be given in reasonably large quantities and hyperventilation begun with 100% oxygen. As soon as feasible, arterial blood gas determinations should be made to guide emergency treatment. If it is believed before operation that a patient is at risk of developing this syndrome a consensus of opinion at the present time is that induction of anesthesia can be carried out safely with a combination of fentanyl and droperidol (Innovar), thiopental, or diazepam and that anesthesia may be maintained with nitrous oxide and oxygen supplemented with the aforementioned induction drugs or narcotic compounds. If muscle relaxation is required it is believed that d-tubocurarine can be used in judicious doses. A useful alternative is spinal, regional, or local analgesia.-George Holcomb
130
GENERAL
CONSIDERATIONS
Recognition of Infection venous Catheters. Surg 62:404-4&S,
Associated
With
Intro-
R. Freeman and 8. King. Br J 1975.
Intravenous alimentation is important in the long-term management of the seriously ill infant. Many centers of pediatric surgery use peripheral veins, leaving the central vein as a last resort because of the serious risk of infection. This paper reports four cases of colonization of intravenous catheters in peripheral veins, causing symptoms of systemic illness but without leukocytosis and with no local sepsis or inflammation at the site of cannulation of the vein. The similarity to colonization of atrioventricular shunts in the treatment of hydrocephalus is referred to, and the importance of suspecting this cause of systemic illness is emphasized. Cure results when the catheter is removed, although a local abscess may then develop and require drainage.--R.B. Zachary A Direct Vasoconstrictor the
Renal
Artery.
Chamberlain.
Effect of Mannitol
S. Temes, 0.
on
L&en, and W.
Surg Gynecol Obstet
141:223
(Au-
gust), 1975.
Mannitol in appropriate concentration can directly affect the renal vessels. The direct effect of mannitol on the renal artery was studied using spiral cut strips of canine renal arteries, Spiral cut strips were equilibrated in KrebsHenseleit bicarbonate buffer at 37°C. The strips contracted when challenged with increasing doses of mannitol. The force of contraction was directly proportional to the dose of mannitol used. Vasoconstriction is a direct effect of mannitol on the renal artery in the dose range of IO-70 mg/ml. This observation may explain some of the seemingly contradictory data which have accumulated in studies using mannitol. Recently published work from the same laboratory has revealed that, depending on the dose, mannitol can produce either an increase or decrease in renal perfusion.-George Holcomb
ANESTHESIA INHALATION Malignant
Hyperthermia.
AND THERAPY C. R. Stephen. South
Med J 68:801 (July), 1975.
Over 500 cases of malignant hyperthermia have been reported with a mortality of more
than 70”;. The cause is unknown, but in susceptible patients a massive disturbance of metabolism develops which results in a tremendous production of heat. There are a few known facts about this syndrome which can help avert or abort it. First, there is a genetic component. With a history of previous occurrences in a family, sharply elevated CPK levels have been found. An abnormally high CPK level preoperatively in the absence of other possible explanations should alert one to the potential for development of this syndrome. It may also occur with a normal CPK level. There are two potential triggering mechanisms known. The first is the use of a potent inhalation anesthetic (halothane, methoxyflurane, fluroxene, cyclopropane, ethyl ether, and possibly enflurane). The second known triggering mechanism is the muscle relaxant succinylcholine. Patients of any age may develop this syndrome, the youngest reported being 3 mo of age. The best single method to determine the onset of this syndrome early is to monitor the patient’s body temperature during the induction of anesthesia. If this increases at a rate of 1°F every IO-15 min and reaches 103°F (39.4”C) one should suspect that malignant hyperthermia is developing. The patient should be cooled as rapidly as possible by applying ice to the body surface, administering cold balanced salt solutions intravenously, flooding open body cavities with cold solutions, giving ice water enemas and stomach lavage with cold fluids. Because metabolic acidosis develops rapidly and the high metabolism causes a great oxygen demand, sodium bicarbonate should be given in reasonably large quantities and hyperventilation begun with 100% oxygen. As soon as feasible, arterial blood gas determinations should be made to guide emergency treatment. If it is believed before operation that a patient is at risk of developing this syndrome a consensus of opinion at the present time is that induction of anesthesia can be carried out safely with a combination of fentanyl and droperidol (Innovar), thiopental, or diazepam and that anesthesia may be maintained with nitrous oxide and oxygen supplemented with the aforementioned induction drugs or narcotic compounds. If muscle relaxation is required it is believed that d-tubocurarine can be used in judicious doses. A useful alternative is spinal, regional, or local analgesia.-George Holcomb