Prediction of difficult airway in school-aged patients with microtia.

BACKGROUND: Because the ear and mandible develop from the first and second branchial arches and first branchial cleft, abnormalities of the ear may be a sign that intubation will be difficult. We hypothesized that children with microtia would have a greater incidence of difficult laryngeal visualization with conventional rigid laryngoscopy compared to those with normal facial anatomy. METHODS: We enrolled 93 consecutive school-aged patients with microtia undergoing the first stage of total reconstruction of the auricle. Age-matched patients with normal facial anatomy served as controls. Each patient was examined for the presence or absence of the five dysmorphic features of hemifacial microsomia: orbital asymmetry, mandibular hypoplasia, ear deformity, nerve involvement, soft tissue deficiency (OMENS classification). After a standardized induction of anaesthesia, the laryngeal view during rigid laryngoscopy was graded. RESULTS: The incidence of difficult laryngeal view was 42% in the patients with bilateral microtia, 2% in those with unilateral microtia and 0% in the controls. CONCLUSIONS: There was a strong positive correlation between the number of involved abnormal anatomical components according to the OMENS classification and the degree of difficult visualization of the larynx in patients with both bilateral and unilateral microtia (Spearman rank order correlation coefficient=0.85 and 0.88, respectively).

Perioperative care of a patient with acute fatty liver of pregnancy.

Acute fatty liver of pregnancy (AFLP) is a late gestational complication with biochemical similarities to the inherited disorders of mitochondrial fatty acid oxidation and clinical similarities to fulminant hepatic failure. The following case illustrates our perioperative management of this rarely encountered disorder.

Anesthesia in a child with severe restrictive pulmonary dysfunction caused by chronic graft-versus-host disease.

Chronic graft-versus-host disease (GVHD) affects 30% to 50% of allogenic bone marrow transplant (BMT) recipients surviving the acute phase. We describe the clinical features and the anesthetic management of a child with a systemic form of GVHD resulting in severe restrictive pulmonary dysfunction.

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.

Lymphocyte-proliferative responses to HIV antigens as a potential measure of immunological reconstitution in HIV disease.

Lymphocyte-proliferative responses (LPRs) to HIV antigens are absent or of low magnitude in the majority of HIV-infected individuals, even early in the disease. However, lymphocytes from 2% to 3% of individuals proliferate very strongly to HIV Env or Gag antigens, and these individuals remain well clinically, without antiretroviral therapy. In established HIV infection, suppression of HIV-replication with potent antiretroviral therapy does not result in the development of strong LPRs to HIV antigens. Large LPRs to HIV antigens can be induced by HIV vaccines in patients with established infection, even though they were not formed in response to infection. Studies must be designed to determine whether large LPRs induced by vaccines administered in conjunction with potent antiretroviral therapy are associated with long-term control of HIV infection.

Clinical management of latex-allergic children.

UNLABELLED: Latex allergy in children with myelodysplasia and urological anomalies is well recognized. We anesthetized 162 children with latex allergy who underwent 267 anesthetics according to a latex-safe protocol. Medication for allergy prophylaxis was not administered. Our patients were 11.6 +/- 5.8 yr old (range 1-31 yr). Primary diagnoses were myelodysplasia, extrophy of the bladder, and cloacal extrophy. These children had many allergies to medications and foods as well as environmental sensitivities. One patient of 162 (1 procedure of 267) had an allergic reaction after injection of an epidural catheter with bupivacaine and fentanyl. No other patient manifested allergy signs or symptoms. Latex-allergic children can be safely anesthetized using a latex-safe protocol without allergy chemoprophylaxis. These patients require avoidance of latex products or the use of latex products that have been thoroughly washed. IMPLICATIONS: This audit of the medical histories and treatment of 162 children with latex allergy who underwent 267 anesthetics indicates that latex-allergic children can be safely anesthetized if exposure to latex in the medical environment is avoided, and that administration of prophylactic medications to decrease the allergic response is unnecessary.

Tuberculosis infection and disease among persons seeking social services in New York City.

SETTING: A large public hospital in New York City. OBJECTIVE: To determine the prevalence of tuberculosis infection and disease in a cohort of indigent persons in New York. DESIGN: Persons seeking social services at any of five community-based organizations in New York City were screened for tuberculosis infection using tuberculin skin testing and a symptom questionnaire. Skin test or symptom positive persons were referred to the Bellevue Hospital Chest Clinic for a chest radiograph and medical evaluation. After this evaluation, patients were classified into a diagnostic category (e.g. tuberculosis infection, tuberculosis disease, no evidence of tuberculosis infection or disease). RESULTS: Of 651 persons screened, 591 (91%) completed the initial evaluation. The tuberculosis infection prevalence for the entire cohort was 41% (95% Confidence Interval [CI], 37% to 45%). Risk factors for infection included residence in a congregate setting, drug use, and birth outside the United States. Human immunodeficiency virus (HIV) infection was not a risk factor for infection. Eleven cases of active tuberculosis were also detected (disease prevalence of 1.7%, 95% CI, 0.85% to 3%). Most of the patients with active tuberculosis had documented HIV infection or clear risk factors for HIV. CONCLUSION: We conclude that tuberculosis infection and disease remain common in populations characterized by poor housing conditions, drug use, and HIV infection. Linking a major medical provider with community-based organizations is an effective means to provide highly targeted screening services to a population at serious risk for disease acquisition and transmission.

Sevoflurane depresses myocardial contractility less than halothane during induction of anesthesia in children.

BACKGROUND: Cardiovascular stability is an important prerequisite for any new volatile anesthetic. We compared echocardiographically derived indices of myocardial contractility during inhalation induction with sevoflurane and halothane in children. METHODS: Twenty children were randomized to receive either halothane or sevoflurane for inhalation induction of anesthesia. No preoperative medications were given. Myocardial contractility was evaluated at baseline and at sevoflurane and halothane end-tidal concentrations of 1.0 minimum alveolar concentration (MAC) and 1.5 MAC. RESULTS: There were no differences between groups in patient age, sex, physical status, weight, or height. Equilibration times and MAC multiples of sevoflurane and halothane were comparable. Vital signs remained stable throughout the study. Left ventricular end-systolic meridional wall stress increased with halothane but remained unchanged with sevoflurane. Systemic vascular resistance decreased from baseline to 1 MAC and 1.5 MAC with sevoflurane. Halothane depressed contractility as assessed by the stress-velocity index and stress-shortening index, whereas contractility remained within normal limits with sevoflurane. Total minute stress and normalized total mechanical energy expenditure, measures of myocardial oxygen consumption, did not change with either agent. CONCLUSIONS: Myocardial contractility was decreased less during inhalation induction of anesthesia with sevoflurane compared with halothane in children. Although the induction of anesthesia with sevoflurane or halothane was equally well tolerated, the preservation of myocardial contractility with sevoflurane makes it an attractive alternative for inducing anesthesia in children.

Validating literature-based models with direct clinical trial results: the cost-effectiveness of secondary prophylaxis for PCP in AIDS patients.

OBJECTIVE: To compare literature-based estimates of the cost-effectiveness ratios of strategies for secondary prophylaxis of Pneumocystis carinii pneumonia (PCP) in AIDS patients with estimates obtained using data from a recent comparative clinical trial. DESIGN: A decision-analytic Markov model with data on drug efficacy and toxicity from both the medical literature and a national randomized clinical trial. Drug costs were from average wholesale prices. Discounted life expectancy, total direct medical costs, and cost-effectiveness were projected in dollars per year of life saved (YLS). SETTING: Hypothetical for the literature-based model, then the clinical trial results from the multicenter AIDS Clinical Trials Group (ACTG Protocol 021). PATIENT POPULATION: Patients with AIDS and a prior episode of PCP. INTERVENTIONS: Strategies included no prophylaxis, TMP-SMX (160/800 mg) daily, or aerosolized pentamidine (300 mg) monthly. Patients experiencing major toxic reactions to either medication would cross over to the other agent. MAIN RESULTS: In the literature-based model no prophylaxis was associated with a projected life expectancy of 1.430 years, and total direct cost of $42,080. TMP-SMX increased life expectancy to 2.051 years and cost to $42,300; for aerosolized pentamidine life expectancy was 2.066 years and cost $43,960. TMP-SMX had an incremental cost-effectiveness ratio of $350 per YLS compared with no prophylaxis; the incremental ratio for aerosolized pentamidine was $2,950 per YLS when compared with no prophylaxis, but rose to $110,880 per YLS compared with TMP-SMX. When data from ACTG clinical trial 021 were utilized in the model, the incremental cost-effectiveness ratio for TMP-SMX compared with no prophylaxis was $720 per YLS; aerosolized pentamidine was not cost-effective, and was "dominated" by TMP-SMX because it was associated with higher costs and shorter life expectancy. CONCLUSIONS: Literature-based cost-effectiveness models are useful in developing health policy before clinical trials are completed. Clinical trial results, when available, can be used to validate and revise these models. For secondary PCP prophylaxis in AIDS patients, TMP-SMX is substantially more cost-effective than aerosolized pentamidine.

Anesthesia crisis resource management: real-life simulation training in operating room crises.

Little formal training is provided in anesthesiology residency programs to help acquire, develop, and practice skills in resource management and decision making during crises in practice. Using anesthesia crisis resource management (ACRM) principles developed at another institution, 68 anesthesiologists and 4 nurse-anesthetists participated in an ACRM training course held over a 2 and a half-month period. The anesthesia environment was recreated in a real operating room, with standard equipment and simulations requiring actual performance of clinical interventions. Scenarios included overdose of inhalation anesthetic, oxygen source failure, cardiac arrest, malignant hyperthermia, tension pneumothorax, and complete power failure. A detailed questionnaire was administered following the debriefing and completed by all participants, documenting their immediate impressions. Participants rated themselves as having performed well in the simulator. Senior attendings and residents rated themselves more highly than did their junior counterparts. The potential benefit of this course for anesthesiologists to practice anesthesia more safely in a controlled exercise environment, was rated highly by both groups. Over one half of respondents in all categories felt that the course should be taken once every 12 months; another third of each group felt that the course should be taken once every 24 months. While no senior attendings believed that the course should be taken once every 6 months, approximately 10% of respondents in other categories that it should. Of respondents in the senior and junior attending category, 5% felt the course should never be taken. Although attendings were less favorable than residents in their rating of the value of the course, both groups were still enthusiastic.

Prospective evaluation by computed tomography and pulmonary function tests of children with mediastinal masses.

BACKGROUND: Our ability to predict respiratory compromise during general anesthesia in a child with an anterior mediastinal mass is limited. Two prior reports have found a correlation between adequacy of ventilation during general anesthesia and the tracheal cross-sectional area obtained from computed tomograms (computed tomography [CT] scans). These and other reports have suggested that pulmonary function tests may provide additional information regarding anesthetic risks, but no studies have evaluated the extent of respiratory compromise in children with an anterior mediastinal mass. METHODS: We prospectively evaluated 31 children with mediastinal masses before 34 surgical procedures. At each evaluation the tracheal area (as a percent of the predicted area on the basis of age and gender) was determined by CT. Pulmonary function tests were performed in the sitting and supine positions. The eleven children with either a tracheal area or peak expiratory flow rate (PEFR) of less than 50% of predicted received only a local anesthetic; the majority of children above these levels (17 of 22) received a general anesthetic. RESULTS: Eleven of 31 patients had significant pulmonary restriction as defined by total lung capacity of less than 75% of predicted. Eight patients had a PEFR in the supine position of less than 50% of predicted. PEFR was lower in the supine than the upright position in all patients (median value of decrease, 12%). In 28 of 34 evaluations the child had a tracheal area greater than 50% of predicted, a criterion proposed for safe utilization of general anesthesia. This latter guideline, however, did not identify all patients with significant impairment of pulmonary function; five patients had a PEFR of less than 50% of predicted but tracheal areas of greater than 50% of predicted. All children were administered anesthetics uneventfully with these guidelines. CONCLUSIONS: Although the tracheal area can be accurately measured with the CT scan, this does not identify all children with mediastinal masses and abnormal pulmonary function. A large mass may produce significant restrictive impairment and hence reduction in PEFR by the intrathoracic volume it occupies and yet not cause tracheal compression. It may also reduce the PEFR by narrowing the bronchi distal to the carina. Currently no CT standards exist for measuring bronchial areas in children. Our study did not evaluate whether impaired pulmonary function as measured by PEFR would be predictive of respiratory collapse during general anesthesia because all were excluded and operated on under local anesthesia. General anesthesia was well tolerated in children with tracheal area and PEFR greater than 50% of predicted. Pulmonary function tests in children with anterior mediastinal masses may add valuable information to the anatomic evaluation obtained by CT scan.

Guidelines for sedation by nonanesthesiologists during diagnostic and therapeutic procedures. The Risk Management Committee of the Department of Anaesthesia of Harvard Medical School.

The increasing use of sedation to enhance patient comfort during diagnostic and therapeutic procedures has been noted by the Joint Commission of Accredited Healthcare Organizations, specialty societies, and the public. Although anesthesiologists, by virtue of training and experience, possess unique qualifications to provide such sedation services, their availability remains somewhat limited by primary commitments to the operating room, intensive care unit, or pain service. The Risk Management Committee of the Department of Anaesthesia of Harvard Medical School has made specific recommendations to the Harvard-affiliated hospitals for anesthesiologists who participate in institutional-level committees in setting guidelines for such services when they are provided by nonanesthesiologists. Specific consideration is given to facilities, backup emergency services, equipment, education and training, issues of informed consent, documentation, and release of patients from medical care. These recommendations emphasize the collaboration of the department of anesthesia and other departments that provide sedation services in formulating policies and procedures that reflect values intrinsic to the practice of anesthesiology.

Morbidity and mortality in pediatric anesthesia.

This article reviews specific considerations for greater anesthetic mortality in the first year of life as well as significant differences in pediatric anesthetic morbidity associated with routine anesthetic management. Clinical conditions such as upper respiratory tract infection, congenital heart disease, and muscle disease are addressed. Loss experience suggests a different profile for pediatric anesthesia.