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M A Rockoff

Publications and source records attributed to M A Rockoff.

At least 19 recordsLinked to original sources
PubMed1996

Cerebral blood flow velocity after mannitol infusion in children.

PURPOSE: There is conflicting evidence as to whether the effect of mannitol on brain bulk arises from haemodynamic, rheologic, or osmotic mechanisms. If mannitol alters cerebral haemodynamics by inducing vasoconstriction, this change should be reflected in cerebral blood flow velocity (CBFV) in the middle cerebral artery (MCA). The purpose of this study was to evaluate the effect of mannitol on CBFV in children. METHODS: Children scheduled for intracranial surgery were enrolled. After a loading dose of 10 micrograms.kg-1 of fentanyl, general anaesthesia was maintained with fentanyl (3 micrograms.kg-1.hr-1), 66% nitrous oxide, and isoflurane (0.2-0.5% inspired). Mean and systolic CBFV (Vm and Vs) and pulsatility index (PI) were recorded with a transcranial Doppler (TCD) directed at the M1 segment of the MCA. Mannitol was administered, 1 gm.kg-1 iv over 15 min. The osmolality (Osm), haematocrit (Hct), mean arterial pressure (MAP), heart rate (HR), and TCD variables were recorded before and 15, 30, 45, and 60 min after the mannitol infusion. RESULTS: Mannitol infusion resulted in an increase in Osm and decrease in Hct (P < 0.05). Heart rate, MAP and arterial carbon dioxide tensions did not change (P > 0.05) during the measuring period. The Vm did not vary from baseline. The Vs and PI both increased briefly (P < 0.01 at 15 min and P < 0.05 at 30 min) after the mannitol, suggesting an increase in resistance distal to the MCA. CONCLUSION: The time course of CBFV changes produced by mannitol corresponds with previous animal data concerning cerebrovascular tone. Our results suggest that mannitol briefly increases cerebrovascular resistance and thereby diminishes cerebral blood volume.

Adolescent↗
PubMed1996

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.

Adolescent↗
PubMed1995

Anesthesia for stereotactic radiosurgery in children.

The development of stereotactic radiosurgery has been a major advance in the treatment of intracranial lesions. By using a stereotactic head frame attached to the skull, large doses of radiation can be delivered precisely to the lesion while sparing surrounding tissues. Although adults can usually undergo this procedure with local anesthesia or conscious sedation alone, children frequently require general anesthesia. This report describes our experience with the anesthetic management of all children who have received this therapy at our institution since the inception of our stereotactic radiosurgery program in 1986 through June 1993. Sixty-eight radiosurgery procedures were performed in 65 patients. Anesthesia time averaged 9.2 h (range, 7-15). Twenty-two patients (ages 11-17; mean 14.3) received local anesthesia alone, two patients (ages 11 and 15) received local anesthesia plus i.v. sedation, and 44 patients (ages 2-14; mean, 7.3) received general anesthesia. Four potentially serious anesthesia-related events occurred; in one child (age 7) receiving general anesthesia, an endotracheal tube obstruction developed during radiosurgery requiring rapid reintubation while the child was still in the head frame; another (age 7) who was undergoing chemotherapy and had neutropenia and rhinitis had a lobar collapse while intubated, requiring mechanical ventilation and endotracheal tube suctioning for lung expansion. Another (age 5) with a recent upper respiratory tract infection had copious endotracheal secretions and sinusitis (ethmoid and maxillary) noted on initial computed tomography scanning and was given antibiotics and decongestants (following nasotracheal extubation), and another (age 15) receiving sedation without endotracheal intubation vomited an undigested meal midway through the procedure while her head was partially immobilized in the head frame.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

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 Children's 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.

Adolescent↗
PubMed1995

Neuroanesthesia.

Children requiring surgical treatment of epilepsy present many perioperative challenges. They demand the skills of a pediatric neuroanesthesiologist who is familiar with the physiologic and psychological needs of the pediatric patient, in addition to understanding the effects of anesthetic agents on the central nervous system. Not only is it important for the anesthesiologist to be aware of the neurosurgeon's specific operative plans, but also it is essential that the neurosurgeon understand the issues facing the anesthesiologist to avoid preventable intraoperative problems and to facilitate an optimal outcome for the patient.

Adolescent↗
PubMed1994

Malignant hyperthermia.

Major advances have occurred in the management of MH since this disorder was first described. Despite the initially high mortality, deaths secondary to MH have dramatically decreased over the past 15 years, which is due in large part to the discovery of efficacious therapy. It is also a result of ever-increasing awareness and appreciation of the syndrome by physicians, other health care providers, and patients. Research has provided many answers to questions about the pathologic mechanisms of this disorder, and an animal model exists for testing new therapies; however, many questions remain. It is hoped that future investigations such as advances in genetic mapping may provide a specific, noninvasive method of predictive testing. It is possible that a complete understanding of MH and its mechanisms could teach us more about the ways anesthetic agents work. For now, identifying individuals at risk, rigorously avoiding exposure to potential anesthetic triggering agents in MH-susceptible patients, and promptly recognizing and treating unexpected MH episodes are the primary means of reducing morbidity and mortality from MH. Interested and informed clinicians and families are the patient's best allies against MH.

Adolescent↗
PubMed1994

Doppler sensor placement during neurosurgical procedures for children in the prone position.

Precordial ultrasonic Doppler devices are effective monitors for detecting venous air emboli (VAE). However, placing an ultrasonic probe on the anterior part of the chest of a prone patient can lead to dislodgment or pressure sores and makes the probe inaccessible to the anesthesiologist. The purpose of this study was to compare placement of a Doppler probe on the patient's back with the traditional precordial site for the ability to detect VAE. We enrolled infants and children undergoing neurosurgical procedures in the prone position in the study. After establishment of general anesthesia and endotracheal intubation, we applied an ultrasonic Doppler probe to the right sternal border of the patient's chest. Anterior insonation was performed with the patient in the supine position. Saline was rapidly injected to verify the efficacy of the monitor (injection test). The patient was turned to the prone position and we placed the Doppler probe between the right scapula and spine. Posterior insonation with saline injection was performed with the patient in the prone position. We obtained positive tests in all patients from the anterior site. Positive tests were obtained from the posterior site in 23 of 24 (96%) children < 10 kilograms (group I), 28 of 39 (72%) children between 10 and 20 kg (group II), and 6 of 22 (27%) children > 20 kilograms (group III). This study demonstrates that a posterior Doppler probe can be effective for monitoring infants at risk of VAE. However, this method is not reliable in children weighting > 10 kg.

Back↗
PubMed1992

DNR in the OR.

Explore the source record for details and available documents.

Anesthesiology↗
PubMed1990

Role of stereotactic radiosurgery with a linear accelerator in treatment of intracranial arteriovenous malformations and tumors in children.

Between 1986 and 1988, 16 children were treated for 10 arteriovenous malformations and 6 recurrent intracranial tumors with stereotactic radiation therapy using a modified Clinac 6/100 linear accelerator. The median age of our patients was 10.5 years. For the group with arteriovenous malformation, follow-up ranged from 6 months to 37 months (median was 20 months). No patient bled during the follow-up period. Five of eight patients with follow-up longer than 12 months have achieved complete obliteration of their arteriovenous malformation by angiogram. The four remaining patients who have not achieved a complete obliteration are awaiting their 2-year posttreatment angiogram. The other patient has been treated within the year and have not yet been studied. Five of the six recurrent tumor patients are alive with a median follow-up of 8 months. The remaining patient was controlled locally, but he died of recurrent disease outside the area treated with radiosurgery. The radiographic responses of these patients have included three complete responses, two substantial reductions in tumor volume (greater than 50%) and one stabilization. Despite previous radiotherapy, there have been no significant complications in these patients. We conclude that stereotactic radiation therapy using a standard linear accelerator is an effective and safe technique in the treatment of selected intracranial arteriovenous malformations and tumors in children. In addition, stereotactic radiosurgery may have unique applications in the treatment of localized primary and recurrent pediatric brain tumors.

Adolescent↗
PubMed1987

Surgical division of craniopagi.

The world's surgical experience on the division of craniopagi is reviewed, and a new case is reported. The problems, including ethical considerations, that must be addressed in selecting patients for operation and in preparing for the procedure are discussed in detail. Hemodynamic stability and the problem of intraoperative gravitational distortion of the brain are addressed. The importance of careful planning is stressed. Survival of the 31 craniopagi after operation is discussed in relation to types of junction.

Brain↗