Mark A. Rockoff

Subclinical Brain Swelling in Children during Treatment of Diabetic Ketoacidosis

Clinically apparent cerebral edema is a rare and often fatal complication of diabetic ketoacidosis. To determine whether subclinical brain swelling occurs more commonly, we obtained cranial CT scans in six children with diabetic ketoacidosis treated with fluid resuscitation and continuous low-dose insulin therapy. Control scans were obtained before hospital discharge. Compared with the scans during convalescence, the early scans of all six children showed a narrowing of the brains ventricular system, compatible with brain swelling. Average changes in diameter were 1.3 +/- 0.1 mm for the third ventricle and 3.7 +/- 0.8 mm for the lateral ventricles (P less than 0.01). In addition, a narrowing of the subarachnoid spaces was subjectively noted during a blind reading of the early scans. Although no single scan was overtly indicative of cerebral edema, the data suggest that subclinical brain swelling may be a common occurrence during treatment of diabetic ketoacidosis in children. Sequential CT scans of the brain may provide a means of evaluating modifications of standard therapy aimed at preventing cerebral edema.

Use of Subdural Grids and Strip Electrodes to Identify a Seizure Focus in Children

For patients with intractable seizures, the best surgical outcome is achieved following precise localization of the seizure focus. Scalp EEG monitoring may be insufficient and chronic subdural invasive EEG monitoring has therefore been advocated. At Childrens Hospital in Boston, 31 children had chronic subdural monitoring from January 1990 through June 1994. The average age at implantation was 11 years. Most patients (22) had placement of grid electrodes combined with strip electrodes to map temporal and/or frontal regions bilaterally. Twenty of the patients eventually had a resective procedure based on the findings. During monitoring, cortical stimulations were performed to localize speech and somatosensory areas. There was only one complication, a subdural hematoma in a patient who had had previous surgery. Chronic subdural EEG monitoring is helpful in precisely localizing seizure foci in pediatric patients; it also allows motor and speech mapping and appears to be a safe modality in children.

Acupressure-Acupuncture Antiemetic Prophylaxis in Children Undergoing Tonsillectomy

BACKGROUND Acupuncture or acupressure at the Nei-Guan (P.6) point on the wrist produces antiemetic effects in awake but not anesthetized patients. The authors studied whether a combined approach using preoperative acupressure and intra- and postoperative acupuncture can prevent emesis following tonsillectomy in children. METHODS Patients 2-12 yr of age were randomly assigned to study or placebo groups. Two Acubands with (study) and two without (placebo) spherical beads were applied bilaterally on the P.6 points; non-bead- and bead-containing Acubands, respectively, were applied on the sham points. All Acubands were applied before any drug administration. After anesthetic induction, acupuncture needles were substituted for the beads and remained in situ until the next day. All points were covered with opaque tape to prevent study group identification. A uniform anesthetic technique was used; postoperative pain was managed initially with morphine and later with acetaminophen and codeine. Emesis, defined as retching or vomiting, was assessed postoperatively. Ondansetron was administered only after two emetic episodes at least 2 min apart. Droperidol was added if emesis persisted. RESULTS One hundred patients were enrolled in the study. There were no differences in age, weight, follow-up duration, or perioperative opioid administration between groups. Retching occurred in 26% of the study patients and in 28% of the placebo patients; 51 and 55%, respectively, vomited; and 60 and 59%, respectively, did either. There were no significant differences between the groups. Redness occurred in 8.5% of acupuncture sites. CONCLUSION Perioperative acupressure and acupuncture did not diminish emesis in children following tonsillectomy.

The effect of propofol on intraoperative electrocorticography and cortical stimulation during awake craniotomies in children

Propofol has been proposed as a sedative agent during awake craniotomies. However, there are reports of propofol suppressing spontaneous epileptiform electrocorticography (ECoG) activity during seizure surgery, while others describe propofol‐induced epileptiform activity. The purpose of this study was to determine if propofol interferes with ECoG and direct cortical stimulation during awake craniotomies in children. Children scheduled for awake craniotomies for resection of epileptic foci or tumours were studied. An intravenous bolus of 1–2 mg·kg−1 followed by infusion of 100–200 μg·kg−1·min−1 of propofol was administered to induce unconsciousness. Fentanyl (0.5 μg·kg−1) was administered incrementally to provide analgesia. After the cortex was exposed, the propofol infusion was stopped and the patient permitted to awaken. Cortical electrodes were applied. ECoG was recorded continuously on a Grass polygraph. Motor, sensory, language, and memory testing were done throughout the procedure. The cortex was stimulated with a hand‐held electrode using sequential increases in voltage to map the relevant speech and motor areas. We studied 12 children (aged 11–15 years) with intractable seizures. The raw ECoG did not reveal any prolonged β‐waves associated with propofol effect. Electroencephalogram spikes due to spontaneous activity or cortical stimulation were easily detected. Cognitive, memory and speech testing was also successful. We conclude that propofol did not interfere with intraoperative ECoG during awake craniotomies. Using this technique, we were able to fully assess motor, sensory, cognitive, speech and memory function and simultaneously avoid routine airway manipulation.

Diabetes insipidus accompanying brain death in children

Diabetes insipidus (DI) developed in 14 of 16 children who satisfied criteria for brain death. The occurrence of DI after an hypoxic/ischemic insult may represent midbrain death and seems to be a clinically useful sign in the diagnosis of brain death in children. In two patients, DI resolved spontaneously; these patients and children without DI may have had small areas of residual cerebral blood flow and brain function. The onset or cessation of DI was temporally associated with the use of dopamine in three patients.

Fatal pulmonary embolism following removal of a central venous catheter

A 1-year-old child developed fatal septic pulmonary embolism upon removal of a central intravenous catheter. Histologically identical material was found in the pulmonary arteries and in the inferior vena cava at the catheter tip site. The pathophysiology of pulmonary embolism occurring during childhood is reviewed.

Cardiac arrest following inhalation induction of anaesthesia in a child with Duchenne's muscular dystrophy.

Cardiac arrest occurred in a 5 1/2-year-old child with suspected Duchenne’ s muscular dystrophy ten minutes following induction of anaesthesia with halothane, nitrous oxide and oxygen. No muscle relaxants were administered. The cardiac arrest was associated with hyperkalaemia, acidosis, myoglobinuria, elevated serum creatinephosphokinase anda 1.6° C rise in temperature. The child made a complete recovery after receiving 90 minutes of cardiopulmonary resuscitation.RésuméUn arrêt cardiaque survenant chez un enfant âgé de 5.5 ans suspect d’avoir une dystrophie musculaire de Duchenne est survenu dix minutes après l’induction de ianesthésie avec halothane, protoxide d’azote et oxygène. Aucun relaxant musculaire n’était administré. L’arrêt cardiaque était associé à une hypercaliémie, acidose, myoglobinurie, une augmentation du CPK et une augmentation de 1.6°C dans la température. L’enfant s’est rétabli complètement après 90 minutes de réanimation cardiopulmonaire.

Anaphylaxis to meperidine.

A 2%-year-old, 12-kg girl was scheduled for elective sigmoidoscopy to evaluate rectal bleeding. She was otherwise in excellent health with no allergies or history of asthma. The only known previous exposure to narcotics occurred at 1% years of age when she was given a cough medication containing codeine. Physical examination was unremarkable. An intravenous infusion was begun and meperidine, 25 mg, was given intravenously. Within 1 minute, facial urticaria developed associated with coughing. Diphenhydramine, 25 mg, was given, but wheezing and cyanosis rapidly occurred. Oxygen by face mask was begun but cyanosis persisted, pulses became unobtainable, and cardiopulmonary resuscitation was instituted. A tracheal tube was inserted and profuse frothy secretions were suctioned from the trachea. Epinephrine was administered intravenously in

Effects of ondansetron on emesis in the first 24 hours after craniotomy in children

Children undergoing neurosurgical resection are at high risk for postoperative nausea and vomiting.Ondansetron, a selective serotonergic (5-HT3) antagonist, is effective in reducing postoperative vomiting in several high-risk populations. In a prospective, randomized study, we compared the prophylactic use of intravenous ondansetron, 0.15 mg/kg, versus placebo for the prevention of emesis in 60 children, aged 2-18 yr, undergoing craniotomies for resective procedures. Patients with preoperative emesis were excluded from the study. All patients were tracheally extubated at the conclusion of surgery, and each episode of emesis during the first 24 postoperative hours was recorded. For the entire 24-h interval, the incidence of emesis in children who received ondansetron (57%) was not significantly different from that in those who received placebo (66%); however, in the first 8 h, the incidence was 25% (ondansetron) vs 44% (placebo) (P = not significant). In those receiving placebo, there was no difference in emesis between patients undergoing operations above versus below the tentorium. Although our sample size was too small to completely exclude any beneficial effect, ondansetron appears ineffective in preventing postoperative emesis in this patient population. (Anesth Analg 1996;83:325-8)

Apnea testing to confirm brain death in children.

The diagnosis of brain death requires absence of respiratory effort. Various protocols for apnea testing in adults have been reported; however, similar protocols have not been established for children. The technique of apneic oxygenation was used on 10 brain-dead children, PaO2 remained over 200 torr in all patients, and the mean Paco2 increase was 4 torr/min. Five min of apneic oxygenation is a safe and effective means of evaluating respiratory activity in initially normocapnic children thought to be brain-dead.