Thomas J. Mancuso

Benign bacteremia caused by Salmonella typhi and paratyphi in children younger than 2 years.

Blood cultures were systematically performed in children under 2 years of age with fever who were seen at 2 health centers in Santiago Chile during the peak months for typhoid fever to determine whether the very low reported incidence of typhoid fever in this age group reflects lack of consumption of the vehicles that transmit Salmonella typhi or whether infant hosts manifest an atypical response that goes unrecognized. S. typhi was isolated from 4 (2%) of the 197 blood cultures S. paratyphi B from 2 (1%) cultures and S. paratyphi A from 1 (0.5%) culture. The clinical syndrome in these infants was mild consisting of fever for 1-5 days and coughing. All infections resolved without complications even though the mothers spontaneously discontinued chloramphenicol therapy when the symptoms disappeared. The results of this study the 1st ot systematically examine the incidence of typhoid fever in children under 2 years indicate that infants become infected at a higher rate (3.6%) than is commonly assumed and manifest a very mild clinical illness.

Functional Maturity of the Coagulation System in Children: An Evaluation Using Thrombelastography

There are quantitative deficiencies in the coagulation system for at least the first 6 mo of life.Clinical experience, however, does not indicate an increased risk of excessive bleeding during surgical procedures. Thrombelastography, a test providing a functional evaluation of coagulation, was used to assess the hemostatic system of pediatric patients under 2 yr of age. Thrombelastographic data were obtained from 237 healthy pediatric patients less than 2 yr of age undergoing elective noncardiac surgery. Five groups were distinguished: under 30 days, 1-3 mo, 3-6 mo, 6-12 mo, and 12-24 mo. Thrombelastography revealed no defects in coagulation when these groups were compared to each other or to adults, indicating a functionally intact hemostatic process even in neonates. Indeed, children less than 12 mo of age were found to initiate and develop clot faster than adults, with the coagulation process slowing to adult rates after 1 yr of age. In addition to defining functional integrity, our data represents a set of pediatric control thrombelastographic values that have not been previously reported and that may become important in understanding coagulation changes that accompany disease states and surgery in pediatric patients. (Anesth Analg 1997;84:745-8)

Ethical concerns in the management of pain in the neonate

The debate about the management of pain in the neonate has continued to evolve over the past 30 years. This controversy can be understood as evolving through now three eras of thought about the effect of pain and its management in newborns and infants. The first generation was characterized by a widespread belief that newborns lacked the complete development of the neuroanatomical and neuroendocrine components necessary to perceive pain. During this period, newborns often received inadequate anesthesia and analgesia for painful procedures, if not no treatment at all. The second generation was heralded by research that demonstrated that newborns did demonstrate similar or even exaggerated physiological and hormonal responses to pain compared with those observed in older children and adults and that exposure to prolonged or severe pain may increase neonatal morbidity. Controversy in this generation focused around the dosage of analgesia to newborns as well as the risks and benefits of pain management techniques. We are now in a third generation of thought about pain in the neonate, defined by intense debate over the significance of a growing number of studies in immature animal models that demonstrate degenerative effects of several anesthetics on neuronal structure. The challenge of this era is to integrate the advances in diagnosis and treatment achieved in previous generations with ongoing adaptation of clinical practice as dictated by research advances in the field. In this review, we examine the evolution of medical thought and ethical concerns regarding pain treatment in the neonate.

Successful and safe delivery of anesthesia and perioperative care for children with complex special health care needs

STUDY OBJECTIVE To determine the utilization of anesthesia resources by children with complex special health care needs. DESIGN Observational, inception cohort study of medical records. SETTING Urban, pediatric, tertiary-care hospital. MEASUREMENTS All general anesthetic cases were screened for preexisting complex special health care needs. Medical records were reviewed for demographic, clinical, and outcome data. MAIN RESULTS 435 children with complex special health care needs accounted for 479 delivered general anesthetic cases. This figure represented 14% of the total 3,437 cases presenting during the study period. It also represented 22% (49 of 224) of all cancellations. Down syndrome was the most identifiable developmental disorder (n = 43, 9%). Another 143 (30%) cases showed preexisting technology dependence. Scheduled surgical procedures (n = 425, 89%) comprised the majority of cases. Intraoperative and recovery room complications occurred in 6 (1%) and 133 (28%) cases, respectively. Eleven (2.3%) cases required unplanned post-anesthetic hospital ward or pediatric intensive care unit admission. Documentation of health care proxy or resuscitation status was not identified in any child under 18 years, and in only 4 of 33 children older than 18 years. CONCLUSIONS Children with complex special health care needs represented one out of 7 of all pediatric general anesthetic cases at a tertiary-care, academic center.

Positive test dose in a neonate with a caudally placed epidural catheter

We present a case of a neonate with an epidural catheter placed via the caudal route after induction of general anaesthesia in whom the test doses of epinephrine‐containing local anaesthetic was positive on two occasions. Remarkable tachycardia was noted after each of two separate injections through the catheter. Blood was never aspirated from the catheter and placement was without difficulty. After the catheter was removed, blood was noted at the tip.

How to best induce anesthesia in infants with pyloric stenosis

In this issue, Scrimgeour et al. report their experience inducing general anesthesia in 269 patients with the diagnosis of pyloric stenosis, 252 of which were anesthetized using an inhalational technique, called a gas induction by the authors (1). The fact that the authors were able to successfully manage the airways of patients with pyloric stenosis without any aspiration events is a testament to the skill and expertise of the anesthesiologists in their institution. However, we disagree with the author’s conclusion ‘Gas induction can be considered for children undergoing pyloromyotomy’. We are perplexed why the authors chose an inhalation technique as patients with pyloric stenosis will have been rehydrated prior to coming for surgery and thus will arrive in the preanesthetic area with a functioning intravenous catheter in place. It seems counterintuitive to us that the authors chose not to use the existing IV to facilitate a more rapid induction of general anesthesia in these children with a high level gastrointestinal obstruction. Aspiration of gastric contents during an anesthetic is an extremely rare event, even in pediatric anesthesia where inhalation inductions are often used, hence conclusions regarding the efficacy of particular induction or anesthetic techniques in prevention of aspiration are difficult to make. However, it is also difficult to argue that infants with pyloric stenosis are not at exceptionally high risk for aspiration of gastric contents. Cook-Sather et al. measured the volume of gastric contents of patients with pyloric stenosis and reported the mean gastric fluid volume suctioned blindly prior to induction of anesthesia was 4.8 ml 4.3 ml kg 1 (2). This volume is 12 times larger than the average volume of gastric contents found in appropriately fasting healthy pediatric surgical population (0.40 0.45 ml kg ) reported in that paper. The authors of the same paper also mention that the gastric volume reported by patients with pyloric stenosis is likely an underestimation as 15/15 patients who had their gastric content suctioned had some residual gastric fluid on endoscopic evaluation immediately after induction and intubation (1). This significant increase in gastric volume warrants taking every precaution possible to prevent reflux of this potentially large acidic volume into the lungs during induction of anesthesia. The author’s of Gas induction for pylorolyotomy state, without reference: ‘. . .it would appear that many centers, including our own, are using the technique in preference to rapid sequence induction and intubation (RSI)’. It is inadvisable for the authors to suggest inhalation induction, and gentle positive pressure ventilation for pyloric stenosis is now the preferred method for induction without any evidence to support this statement. Buvet et al. reported recently in Anesthesiology that even gentle mask ventilation, with pressures of 15 cm H2O resulted in a probability of gastric insufflation of 35% as seen by real-time ultrasonography (3). The risk of aspiration is only increased with even gentle positive pressure ventilation in infants with pyloric stenosis. These infants will, of course, not cooperate with an inhalation induction, no matter how gentle the practitioner. In addition, infants often have partial upper airway obstruction during inhalation induction and require higher airway pressures. These considerations, in addition to the aforementioned high intestinal obstruction, are the bases for the common use of a RSI in the induction of infants with pyloric stenosis. We agree with the author’s penultimate statement ‘This case series does not prove the superiority of gas induction compared with the other techniques. . .’ Given the lack of evidence suggesting a clear superiority of inhalation induction over RSI, but countered with the very real and potentially very serious event of aspiration of acidic gastric content, we find it difficult to justify not using an IV induction of general anesthesia, and absent a contraindication, an RSI technique for patients with pyloric stenosis. And while the authors do temper their advocacy for inhalation technique for patients with pyloric stenosis by commenting: ‘A well designed, prospective trial and work defining current international practice would be welcome’, we are not certain that the equipoise needed among anesthetists in order to conduct such an investigation exists.

Sickle Cell and Anesthesia: Do Not Abandon Well-established Practices without Evidence

Hemoglobin: Structure and Function Hemoglobin (Hb) is composed of two pairs of sub-units containing protoheme and globin.. The various globin chains differ in the number and sequence of amino acids and are designated by α, β, γ, δ, e, ζ, and θ. Normal adult RBCs have three types of hemoglobin: HbA (α2,β2) approx. 95%, HbA2 (α2δ2) approx. 2.5 %, and HbF (α2γ2). The spatial relationship of the four subunits determines oxygen affinity as well as physical properties such as Hb solubility and stability. At birth red cells contain 70-90 % HbF until 2-4 months of age. Beta chain production begins shortly before birth and gamma chain production wanes resulting in a normal adult profile by age 4 months. Thus disorders of the beta chain will not manifest themselves in the first few months nor be identified by precipitation screening tests. Hemoglobinopathies can result from either production of an abnormal hemoglobin chain or by under production of a given chain. The most common mechanism of the former type is the result of a single substitution of one amino acid for another on the protein chain, which occurs with sickling disorders. Underproduction of a given chain results in a group of disorders known as thalassemias.

Pediatric Research, Risk, and Paravertebral Blocks.

• Volume 120 • Number 5 www.anesthesia-analgesia.org 987 Copyright

Equipment and Monitoring

A 2-month-old, 5-kg baby, born at term without apparent complications, is scheduled to come to the OR emergently for evacuation of a subdural hematoma and repair of depressed skull fracture as a consequence of presumed child abuse. VS: HR 130 bpm, RR 22/min and crying, BP 75/50 mmHg, and Hct 30%. There is a 22 ga. IV in place in the left saphenous vein, and it seems to be running well.

Ethical and Medicolegal Considerations

Ethical and medicolegal dilemmas frequently arise in the perioperative care of term and preterm neonates. This requires that pediatric anesthesiologists have a working knowledge of these ethical concerns in order to provide comprehensive care. Here we provide a concise review of common ethical challenges in the perioperative care of term and preterm neonates utilizing a widely accepted decision-making framework and then examine fundamental medicolegal concerns in neonatal care.