Reduction of serum gonadotropin concentrations after parathyroidectomy

1237

CURRENT LITERATURE

cases occurred during anesthesia for head and neck surgery. This article reports on a prospective study involving the anesthetic management of patients following an aborted pediatric surgical procedure secondary to episodes of MH (five), or because of a strong family history of MH (three). The management protocol consisted of a thorough history and physical; preoperative CPK measurement; avoidance of succynlcholine and the inhalation agents halothane, erthrane, and isoflorance; using general anesthesia consisting of narcotics, barbiturates, tranquilizers, nondepolarizing muscle relaxants, and nitrous oxide; an anesthesia machine free of potent inhalation agent; monitoring of electrocardiogram, blood pressure, urine output, and core body temperature up to 48 hours postoperatively; biopsies of vastus lateralis muscle after completion of all surgical procedures, and subjecting the muscle to a caffeineihalothane contracture test. All patients received general anesthesia without clinical signs of MH, and all biopsies showed a positive contracture test. The cellular defect responsible for the crisis is still thought to be an abnormality of the calcium reuptake mechanism of the sarcoplasmic reticulum in skeletal muscle. When muscle contraction is triggered, relaxation is blocked secondary to ATP depletion, resulting in rigidity and increased oxygen consumption. The net effect is acidosis and hyperthermia. Cellular ionic gradients are unable to be maintained, which results in cell death, rhabdomyolysis, and release of myoglobin. Myoglobin nephrotoxicity may cause acute renal failure. Controversy still exists around the preoperative management with dantrolene. Although some recommend a dose of 2 mglkg prior to induction, these authors avoid its use due to clinically significant respitatory muscle weakness and incapacitation. The use of ester versus amide local anesthetics is also still controversial. However, ester local anesthetic, specifically if required in large amounts, is the best choice. The authors note that as many as 25% of patients exhibiting MH reactions may have had prior uncomplicated anesthetic exposure. They conclude that general anesthesia may be given safely to pediatric patients with known or suspected MH undergoing surgery provided certain measures are taken-T.B. WELCH Reprint requests to Dr Abdul-Rasool: Department of Anesthesiology, UCLA Medical Center, 10833 LeConte Ave, Los Angeles, CA 90024.

Blood Transfusions and Recurrence in Head and Neck Cancer. Jackson RM, Rice DH. Ann Otol Laryngol 98:171, 1989 One hundred head and neck cancer patients treated either surgically or with combined (SurgicaVradiation) therapy, all of whom had a 5-year follow-up, were reviewed relative to perioperative blood transfusion. The recurrence rate for laryngeal cancers was 14% for those not receiving blood and 65% for those who did. For cancers of the oral cavity, pharynx, nose, or sinuses, recurrence rates were 31% without transfusion and 71% with transfusion. These associations imply that blood transfusions adversely affect patients with head and neck cancers, similar to decreased survival reports in other transfused cancer patients. The mechanism needs elucidation.-G.H. SPERBER Reprint requests

to Dr Rice: Department

of Otolaryngoiogy,

University of Southern California, Medical Center, 1200 N. State St, Los Angeles, CA 90033.

BOX 795,

Treatment and Prognosis of Ameloblastoma-Indication for Marsupialization. Ueda M, Furune A. Yanbe M, et al. J Jpn Stomatol Sot 38:54, 1989 Clinical, radiographic, and histologic analysis of 72 ameloblastomas is reported, and the efficacy of marsupialization in the treatment of the disease is evaluated. The mean age of the patients was 35.5 years, with a range of 6 to 74 years. The mandible was the site of involvement in 65 cases and the maxilla in the remaining seven cases. Clinically, the tumors were of the solid type in 10 cases, unicystic in 40 cases, and of a mixed type in 22 cases, whereas the lesions were radiographically unilocular in 13 cases and multilocular in 59 cases. Histologic examination showed that 36 cases were of the acanthoma type, which was followed in order of frequency by follicular type (14 cases), plexiform type (eight cases), stellate cell type (eight cases), primitive type (six cases), and basal cell type (none). Recurrence of the tumor occurred in 6.7% of nine cases treated by segmental resection, 9.1% of 26 cases treated by partial resection, and 59.3% of 32 cases treated conservatively. Marsupialization, consisting of excision of a circular disc of tissue that included the oral mucosa, underlying bone, and the wall of the tumor, was done in 26 of the 32 conservatively treated cases. When clinical and radiographic reduction in size of the tumor, with or without regeneration of bone, was regarded as an indication of effective therapy in the conservatively treated cases, the treatment was effective in 65.4% of the patients, most of whom were under 30 years of age. The result was not related to the size of the tumor, but it was effective in 83% of clinically unicystic lesions as compared with 14% of solid lesions. Radiographically, however, effective cases were almost evenly distributed between the unicystic (62%) and multicystic (69%) types. The success rates for the treatment for the acanthoma, follicular, plexiform, stellate cell, and primitive types were 69%, 60%, 67%, 67%, and 50%, respectively. No statistical differences were found among the groups.-T. NAKAJIMA Reprint requests to Dr Ueda: Department of Oral Surgery, School of Medicine, Nagoya University, 65, Tsurumaicho, Showaku, Nagoya City 466, Japan.

Reduction of Serum Gonadotropin Concentrations After Parathyroidectomy. Kristoffersson A, Grankvist K, Jarhuh J. Acta Endocrinol 120:379, 1989 Release of FSH and LH from the anterior pituitary is possibly calcium dependent. Controversy exists as to whether fluctuations in plasma calcium affect the release of gonadotropins in humans. Fifteen postmenopausal women with moderate hypercalcemia were studied. Each patient was rendered normocalcemic by removal of a single parathyroid adenoma. Serum calcium, PTH, FSH, LH, and estradiol were measured before this surgery and 12 months afterwards. Significant decreases in serum LH and FSH concentrations were identified after normalization of the serum calcium. There was no statistical difference in the pre- and post-operative estradiol cells. This article concludes that chronic hypercalcemia in postmenopausal women seems to stimulate gonadotropin secretion. It is highly unlikely that these moderately elevated LH and FSH serum levels are clinically relevant. -J.M. MCCOY

1238 Reprint requests Hoglandssjukhuset,

CURRENT LITERATURE

to Dr Jarhult: Department S-575 00 Eksjo, Sweden.

of Surgery,

Postanginal Sepsis. Shapiro J, Fried MP, Strome M. Head Neck Surg 11:164, 1989 Septicemia following pharyngitis, called postanginal sepsis, is a process in which infection spreads via tonsillar veins or lymphatic channels to the internal jugular vein. There, a thrombophlebitis can occur that can release septic emboli, which produce varying symptoms depending on the endpoint of embolization. This article reviews the English language literature relating to postanginal sepsis and presents three new cases. The authors found that the average length of time between the onset of sore throat and the development of systemic septic symptoms was 9 days (range 0 to 22 days). The neck examination was usually abnormal, with the most common symptom being pain along the anterior border of the sternocleidomastoid muscle. The most common organisms found on positive blood culture were Fusobacteria. The most frequent problem due to systemic emboli was pulmonary involvement with infiltrates and pleural effusions. Other signs and symptoms of postanginal sepsis include high spiking fevers, chills, malaise, and leukocytosis. Useful studies on patients with postanginal sepsis included neck ultrasound or CT scan looking for abscess cavities. The mortality rate since the induction of penicillin is 8%. Management of a patient with suspected postanginal sepsis includes obtaining a history of antecedent pharyngitis. A careful neck and oropharyngeal examination should be performed. If the neck is tender a CT scan should be ordered, along with blood cultures. Most of the organisms likely to cause postanginal sepsis are sensitive to penicillin or clindamycin. The discovery of an abscess should prompt surgical exploration for drainage and possible ligation and resection of any thrombosed portions of the internal jugular vein. In most cases recovery is prolonged.-J.R. HUMP Reprint requests MA 02115.

to Dr Shapiro: 333 Longwood Ave, Boston,

Comparison of Pulse Oximeters: Effects of Vasoconstriction and Venous Engorgement. Wilkins CJ, Moores M, Hanning CD. Br J Anaesth 62:439, 1989 Pulse oximetry is an emerging standard for anesthetic monitoring. Although accurate under steady-state conditions, detection may be impaired in the presence of vasoconstriction (CNSTR) or venous congestion (CONG). This study compared the accuracy of five pulse oximeters under these conditions. Oximeters tested were: Ohmeda 3700, Novametric 500, Criticare Systems Inc. model 501, Accusat (Datascope Corp), and Lifestat 1600 (Physiocontrol Corp). Ten healthy volunteers had finger probes from each machine placed in a randomly assigned manner, and a Biox III oximeter was applied to the subjects’ ears for safety monitoring. Each subject was twice given a hypoxic gas mixture (10% oxygen, 90% nitrogen) to breathe for 2 minutes with control desaturation values recorded. A blood pressure cuff was inflated to 40 mm Hg on the upper arm to induce venous congestion, and two episodes of hypoxia induced as before. To induce vasoconstriction, a cooled, water-filled plastic bag was placed over the forearm for 10 minutes, and again hypoxia induced. All data were recorded on a calibrated chart re-

corder. Time for detection of desaturation was not significantly different among all oximeters in either control, CNSTR, or CONG groups. All oximeters had significant increases in detection time of two to three times the control value when CNSTR or CONG conditions were present, causing a mean delay of 150 seconds to detection of hypoxic insult. Of all the units tested, the Novametrix failed to detect the maximum desaturation that occurred under CNSTR or CONG conditions. The same unit failed to give an alarm of poor quality signals while other units gave clear warning under CNSTR or CONG conditions. The authors warn that presence of a normal pulse signal does not imply that perfusion is adequate for detection of hypoxia. They state that new versions of several oximeters were introduced after the study began (including Novametrix) and may perform differently than those tested.-J. DEMBO Reprint requests to Dr Wilkins: University Department of Anaesthesia, General Hospital, Gwendolen Rd, Leicester LES 4PW, England.

The Effect of Flumazenil on the Recovery Time of Dental Patients Sedated With Diazepam. Young ER, Kestenberg SH, Toal CB. Anesth Prog 36:46, 1989 Diazepam, which is used widely for sedation in dentistry, has a long half-life that may cause prolonged sedation. Flumazenil is an imidazobenzodiazepine that antagonizes the effects of benzodiazepines by binding to the same receptors. This study examined the efficacy of flumazenil in shortening the recovery following diazepam sedation. Twenty-one healthy young men undergoing restorative dentistry were randomly assigned to receive flumazenil or placebo. Each group was sedated with diazepam 0.15 mg/kg intravenously, and local anesthetic was given. Fifteen minutes after the diazepam dose, flumazenil 0.015 mg/kg or placebo vehicle was given IV in doubleblind fashion. Psychomotor function was tested presedation and postsedation at S-minute intervals using the Trieger test, digit-symbo1 substitution (DSS), Romberg test, and an independent assessment by the dentist, nurse, and patient. Significant differences between groups included better performance on the Trieger test and DSS only at 5 and 10 minutes; after 15 minutes no differences were noted. The authors attribute these tindings to the natural cessation of diazepam effects after 15 minutes. They conclude that, although flumazenil was useful in improving psychomotor performance during the immediate postsedation period, it cannot be recommended for routine use following benzodiazepine sedation.-J. DEMBO Reprint requests to Dr Young: Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada.

The Correlation of Specific Variables of Tumor Differentiation With Response Rate and Survival in Patients With Advanced Head and Neck Cancer Treated With Induction Chemotherapy. Ensley JF, Kish JA, et al. Cancer 63: 1487, 1988 Conventional tumor grading correlates poorly with the biological response and survival rates in patients with advanced squamous cell cancers of the head and neck (SCCHN) treated with cisplatinum combinationinduction therapy. Because conventional grading may be