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Biomedical subjects

H W Karl

Publications and source records attributed to H W Karl.

23 records · Page 2Linked to original sources

Epinephrine-halothane interactions in children.

Cutaneous infiltration of dilute solutions of epinephrine for hemostasis during halothane anesthesia can result in ventricular dysrhythmias. Our clinical experience, published reports, and a study comparing piglets with adult swine suggest that children may be less susceptible than adults to dysrhythmias under these conditions. We therefore undertook a prospective survey of heart rate and rhythm in halothane-anesthesized children who received subcutaneous epinephrine for hemostasis. Mass spectrometry was used to quantify end-tidal halothane and to avoid hypercarbia. In 83 children anesthesized with halothane, we continuously recorded ECG, heart rate (HR), end-tidal halothane (ETHalo), and carbon dioxide (ETCO2). The surgeons injected 0.4--15.7 micrograms/kg of epinephrine (in saline or 1% lidocaine) to provide hemostasis at a variety of sites. No child developed a ventricular dysrhythmia. One child had self-limited premature atrial contractions (PAC). Sixty-three children had some increase in heart rate after epinephrine injection, while seven increased their HR 15% or more above pre-injection levels. No relation between any increase in HR and epinephrine dosage, ETHalo, ETCO2, physical status, or age was found by multiple linear regression; however, HR was increased significantly in patients receiving epinephrine in head and neck sites other than the palate. The authors conclude that children tolerate higher doses of subcutaneous epinephrine than adults during halothane anesthesia. The arrhythmogenic dose of epinephrine in children receiving halothane has yet to be determined, but at least 10 micrograms/kg of epinephrine infiltration may be used safely in normocarbic and hypocarbic pediatric patients without congenital heart disease. The presence of PAC and tachycardia emphasize the need for continuous ECG monitoring and caution during halothane anesthesia with epinephrine injection.

Adolescent↗

Increased serum immunoreactive gastrin levels in idiopathic hypertrophic pyloric stenosis.

The serum immunoreactive gastrin (IRG) level in infants with confirmed idiopathic hypertrophic pyloric stenosis (IHPS) has been determined and compared to that found in vomiting infants without IHPS, in normal infants, and in normal adults. The mean serum IRG level of normal infants (103 +/- 9 pg/ml (mean +/- SEM) exceeded that of normal adults (28 +/- 5 pg/ml). The preoperative mean serum IRG level in IHPS infants (256 +/- 26 pg/ml) was significantly higher than that of both normal infants and vomiting infants without IHPS (93 +/- 9 pg/ml). Twenty-five per cent (5/20) of the IHPS infants had serum IRG levels within the upper range of normal infants. Fasting serum IRG levels in IHPS infants were not altered immediately by pyloromyotomy. The results from this study suggest a relationship between gastrin and idiopathic hypertrophic pyloric stenosis.

Adolescent↗

Mortality and morbidity of pancreatic injury.

Pancreatic trauma, regardless of etiology, has been consistently associated with a mortality of 20 percent and enormous morbidity. Twenty-five pancreatic injuries, including four solitary wounds of the pancreas, were analyzed to determine why pancreatic trauma should have such an adverse prognosis. Eleven patients were victims of blunt trauma and fourteen sustained gunshot wounds. There were no stab wounds. The important determinants of mortality were associated injuries to major vessels, wounds of the head of the gland, and failure to adequately control leaking exocrine secretion. All four deaths were directly related to massive hemorrhage; in two instances leakage of pancreatic juice was also implicated. With the exception of benign solitary blunt wounds of the pancreas to the body of the gland immediately ventral to the spinal column, an injury of the pancreas is evidence that the abdomen has been subjected to severe trauma, which predisposes the patient to a high mortality and morbidity. The pancreatic injury, interacting with other abdominal injuries, is likely to be a cause of significant mortality and to result in complications that will prolong the patient's hospitalization.

Abdominal Injuries↗

Preanesthetic preparation of pediatric outpatients: the role of a videotape for parents.

Expanded outpatient surgery for pediatric patients makes it difficult to provide an unhurried and thorough preoperative visit. A useful component could be a videotape to be seen by parents at the time of their initial hospital visit. For this study, a videotape was made that included an actual induction of anesthesia procedure, information about pediatric anesthesia, and a discussion of the risks of injury or death during anesthesia. To decrease anxiety from discussion of risk, monitoring equipment was shown and explained. This survey investigated whether, after seeing the tape, the parents of children scheduled for outpatient surgery thought they were better informed and less anxious about the child's anesthetic. During a preoperative clinic visit, an interviewer introduced the tape and its purpose to 31 parents of 25 children, then asked a series of standard questions. When asked directly, most parents (74%) said the film did not change their concerns about the anesthetic, although 42% of the parents of the children with no surgical history reported decreased concern. In contrast, 84% to 97% of the parents considered seven specific aspects of the film to be helpful in reducing concern. Half were reminded of issues to be discussed with the child's anesthesiologist. Most parents (65%) appeared to accept discussion of the risk of perioperative death, although some had strongly negative reactions. The results suggest that a supportive preoperative tape can acquaint parents with the basis for anesthesiologists' concerns and facilitate the preoperative visit. Seeing an actual anesthetic may help to reassure parents about the anesthetic care their children will receive.(ABSTRACT TRUNCATED AT 250 WORDS)

Ambulatory Surgical Procedures↗

Side effects of triazolam in children.

PURPOSE: This study examined the incidence of side effects occurring with three doses of orally administered triazolam in children undergoing restorative dental procedures. METHODS: Thirty children, aged 39-81 months, participated in the study. The children were pretested for gait ataxia, amnesia, visual acuity, stereoscopic depth perception, and diplopia during a screening session. In a subsequent appointment, children received one of three triazolam dosages (0.005, 0.015, and 0.030 mg/kg) prior to dental treatment. Dosage assignment was random and double blind. Each child received a single triazolam dosage. Tests for gait ataxia, amnesia, and visual disturbances were repeated following drug administration. RESULTS: The proportion of children experiencing ataxia, amnesia, and diplopia increased with increasing triazolam dosages. The 0.030-mg/kg triazolam dosage impaired visual acuity and stereoscopic depth perception. CONCLUSION: Triazolam produces ataxia, amnesia, and diplopia in a dose-dependent manner in children.

Administration, Oral↗