Chronic daily headache and medication-induced headache.
Takase Y.
Department of Neurology, Toyonaka Municipal Hospital.
Chronic daily headache (CDH) and medication-induced headache are refractory headaches to treatment. I evaluate the classification and pharmacological treatment of CDH and medication-induced headache. The subjects of this study are 508 patients with CDH (out of 2,241 patients with chronic headache who were examined and treated in Toyonaka Municipal Hospital for six years from November 1997 to October 2003). CDH was classified into three types of chronic migraine in 232 cases (45.7%), chronic tension-type headache in 223 cases (43.9%) and new daily-persistent headache in 53 cases (10.4%). 245 cases overused medication (analgesic in 230 cases, ergotamine in eight cases and triptan in seven cases). 108 cases abused medication (analgesic in 95 cases, ergotamine in seven cases and triptan in six cases). For treatment, muscle relaxants, calcium-channel blockers, tricyclic antidepressants, selective serotonin reuptake inhibitors, antiepleptic drugs and leukotriene receptor antagonists were administered to 231 patients for two months from September to October 2003. Awareness of CDH and medication-induced headache is important to physicians who treat patients with headache.


National trends in nonoperative care for nonspecific back pain.

BACKGROUND CONTEXT: Few empirical data are available that document changes in population-based rates for the evaluation and treatment of nonspecific back pain. PURPOSE: To determine the extent of change in the pattern of outpatient evaluation and treatment of nonspecific low back pain in the United States between 1987 and 1997. STUDY DESIGN AND SETTING: The 1987 National Medical Expenditure Survey and the 1997 Medical Expenditure Panel Survey, two nationally representative surveys with similar sampling methods and questions, were used. PATIENT SAMPLE: Noninstitutionalized adults in the United States. OUTCOME MEASURES: Changes in rates of any health service for nonspecific back pain and occurrence of provider-specific care and types of services provided. Changes in the prescription of specific medication classes (ie, nonsteroidal anti-inflammatory drugs [NSAIDs], muscle relaxants, nonnarcotic and narcotic analgesics) were also investigated. RESULTS:Overall rate for outpatient treatment for nonspecific back pain in the US population was relatively stable over the decade (4.48% in 1987, 4.53% in 1997, p=.85). Among those receiving care, the proportion receiving physician care increased from 64% in 1987 to 74% in 1997 (p<.001), whereas those obtaining care from physical therapists increased from 5% to 9% during the same time period (p<.01). The proportion of respondents receiving NSAIDs, muscle relaxants, nonnarcotic analgesics and narcotic analgesics remained stable. However, the mean number of patient visits in which these medications were prescribed increased from 2.0 to 3.9 over the decade (p<.001). The proportion of individuals receiving chiropractic care (p<.01) and X- rays (p<.001) were lower in 1997 than 1987. CONCLUSIONS:The national pattern of health care for nonspecific low back pain observed in the present study serves as a basis for future investigations into the management of this major public health problem. Findings suggest that perhaps a duplication of care is partly responsible for the high degree of health care utilization in this population.

The effect of use of pyridostigmine and requirement of vecuronium in patients with myasthenia gravis.

CONTEXT: Patients with myasthenia gravis receive pyridostigmine, an anticholinesterase agent, as a part of therapy. These patients demonstrate a heightened sensitivity towards non-depolarising muscle relaxants. Continuing pyridostigmine till the day of the surgery or omitting it on the night before surgery could provide variable results with regards to the effect of vecuronium. AIMS: Myographic evaluation of a dose of vecuronium in patients with myasthenia gravis on pyridostigmine therapy. SETTING AND DESIGN: A randomised, double-blind, clinical study conducted in a teaching hospital. SUBJECTS AND METHODS: Medically (oral pyridostigmine) well-controlled adult patients with myasthenia gravis who were posted for thymectomy, were randomly divided into two groups. Patients in Group 1 received their last dose of pyridostigmine on the night before surgery while those in Group 2 received even the morning dose of the drug on the day of surgery. Neostigmine (1-2 mg) intravenously was used as rescue medication. Vecuronium (0.01 mg/kg) was used for intubation and muscle relaxation during trans-sternal thymectomy and its effect was reversed using neostigmine and atropine. RESULTS: Fourteen patients (7 in each group) belonging to both sexes were enrolled in the study. The intubating dose of vecuronium showed quicker onset time (155 sec or 2.7 min approx.) and peak effect (99% T1 suppression) in patients belonging to Group 1, and 3/7 (43%) complained of respiratory discomfort while waiting for surgery. By giving the morning dose of pyridostigmine (Group 2), an identical intubating dose of vecuronium showed relative resistance (peak effect-97% T1 suppression) and delayed onset time (198 sec approx.). However, the reversal was complete at the end of surgery in both the regimens. CONCLUSIONS: Omission of the pyridostigmine dose on the day of surgery predisposed patients with myasthenia gravis to the possibility of respiratory discomfort and sensitivity to vecuronium. Continued administration significantly prolonged the onset time of vecuronium and the patients required a higher dose of vecuronium.

Postoperative hyperthermia of unknown origin treated with dantrolene sodium.
Inada H, Jinno S, Kohase H, Fukayama H, Umino M.
Section of Anesthesiology and Clinical Physiology, Department of Oral Restitution, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. inada.anph@tmd.ac.jp
An 11-year-old girl was scheduled for alveolar cleft bone grafting with an iliac bone under general anesthesia. Anesthesia was performed with 70% nitrous oxide, 30% oxygen, and propofol. On the first and second postoperative day, persistent hyperthermia was observed. Because the administration of diclofenac sodium had not been effective for the hyperthermia, dantrolene sodium was given. Her body temperature gradually dropped and returned to normal level on the fifth postoperative day. The hyperthermia in the present case might have been caused by a rapidly elevated muscle metabolism in response to pain and stress after the propofol anesthesia. The oral administration of dantrolene sodium successfully lowered the patient's high body temperature.


Experience with removing Palmaz stents with a rigid bronchoscope.
Tsai HL, Liu C, Chen PT, Soong WJ, Chang WK, Chin T, Wei CF.
Division of Pediatric Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan.
BACKGROUND: The Palmaz stent can relieve congenital malacia or stenosis of airway, but reports on the indications and results of stent removal are rare. The authors report their experience in removing Palmaz stents and discuss the indications for removal. METHODS: Thirteen stents in 12 patients were removed by a rigid bronchoscope for various reasons. The indications were expected recovery (n = 5), severe granulations and expected recovery (n = 2), stent collapse (n = 2), and stent migration and/or fracture (n = 4). RESULTS: The course after removal was smooth in 9 patients and complicated in 3. The indications for stent removal in these 3 complicated cases were all expected recovery. One of the 3 complicated cases needed emergent cardiopulmonary bypass and tracheostomy for a collapsed stent that occluded airway, 1 failed for intractable bleeding, and 1 failed for intense vagal reflex causing cardiac arrest. At 6 months of follow-up, satisfactory results were seen in all but one case that needed further procedures for an iatrogenic tracheoesophageal fistula. CONCLUSIONS: Most Palmaz stents can be removed smoothly with a rigid bronchoscope; however, lethal complications can happen. The authors suggest that indications for stent removal should be intractable airway symptoms caused by the stent rather than expected recovery. muscle relaxants / relaxant should be avoided during anesthesia to maintain spontaneous breathing, and cardiopulmonary bypass should be on standby.


Characteristics and a functional implication of Ca(2+)-activated K(+) current in mouse aortic endothelial cells.

We employed the patch-clamp technique to investigate a Ca(2+)-activated K(+) (K(Ca)) current in cultured mouse aortic endothelial cells (MAECs). In the whole-cell mode, an increase in cytosolic [Ca(2+)] ([Ca(2+)](i)) to 2 micro M activated an outwards current. The [K(+)](o)-dependent change of the reversal potentials agreed well with the predicted Nernstian relation, suggesting that it was a K(Ca) current. The Hill coefficient (4) and EC(50) (740 nM) were obtained from the current/[Ca(2+)](i) relationship. Iberiotoxin (50 nM) or apamin (200 nM) failed to inhibit the current, whereas TEA (10 mM) suppressed the current to 73.6+/-1.6% of control ( n=9). The intermediate-conductance, Ca(2+)-activated K(+) (IK(Ca)) channel blockers charybdotoxin (50 nM), clotrimazole (10 micro M) and econazole (10 micro M) inhibited the K(Ca) current to 10.5+/-1.3% ( n=6), 16.6+/-3.1% ( n=6), and 19.3+/-2.5% ( n=5) of control, respectively. The IK(Ca) channel openers chlorzoxazone, zoxazolamine and 1-ethyl-2-benz-imidazolinone and the Ca(2+)-activated Cl(-) channel blocker niflumic acid activated the K(Ca) current. In inside-out patches, the single-channel conductance was 17.7 pS in symmetrical K(+) solutions. RT-PCR analysis showed transcripts of the murine IK1 channel (mIK1) in MAECs. The IK(Ca) channel blockers inhibited the ATP-induced [Ca(2+)](i) increase in MAECs and the endothelium-dependent relaxation of mouse aortic rings. In addition, the IK(Ca) channel openers augmented ATP-induced [Ca(2+)](i) increase in MAECs and evoked endothelium-dependent relaxation of mouse aorta. These results suggest that an mIK1-like channel mediates the native IK(Ca) current in MAECs and may contribute to endothelium-dependent relaxation by modulating MAEC [Ca(2+)](i).

Reduction in the incidence of awareness using BIS monitoring.

BACKGROUND: Explicit recall (ER) is evident in approximately 0.2% of patients given general anaesthesia including muscle relaxants. This prospective study was performed to evaluate if cerebral monitoring using BIS to guide the conduction of anaesthesia could reduce this incidence significantly. PATIENTS AND METHODS: A prospective cohort of 4945 consecutive surgical patients requiring muscle relaxants / relaxant and/or intubation were monitored with BIS and subsequently interviewed for ER on three occasions. BIS values between 40 and 60 were recommended. The results from the BIS-monitored group of patients was compared with a historical group of 7826 similar cases in a previous study when no cerebral monitoring was used. RESULTS: Two patients in the BIS-monitored group, 0.04%, had ER as compared with 0.18% in the control group (P < 0.038). Both BIS-monitored patients with ER were aware during intubation when they had high BIS values (> 60) for 4 min and more than 10 min, respectively. However, periods with high BIS = 4 min were also evident in other patients with no ER. Episodes with high BIS, 4 min or more, were found in 19% of the monitored patients during induction, and in 8% of cases during maintenance. CONCLUSIONS: The use of BIS monitoring during general anaesthesia requiring endotracheal intubation and/or muscle relaxants / relaxant was associated with a significantly reduced incidence of awareness as compared with a historical control population.

Awareness under general anesthesia.

General anesthesia aims to eliminate patients' awareness of excruciating pain during surgery. Nevertheless, rare occurrences of patient awareness continue because the problem is not yet completely preventable. One study puts the incidence of awareness at 0.18% for patients receiving muscle relaxants / relaxant and at 0.10% for patients not given relaxant drugs. Awareness experiences frighten patients and impact their implicit and explicit memories in ways that can leave a lifetime of residual emotional and psychological problems ranging from sleep disturbances, nightmares, and daytime anxiety that may subside with time to development of post-traumatic stress disorder. Most anesthetists monitor depth of anesthesia by assessing intraoperative hemodynamic responses to surgical stimuli--an approach questioned by some authors. Several depth-of-anesthesia monitors are available, but there is no ideal monitor that is 100% reliable. This review provides an overview of literature that reports findings associated with the monitoring and occurrence of intraoperative awareness. These studies indicate assessment methods that can be trusted when we provide general anesthesia and what measures can be taken to prevent recall by patients under general anesthesia.

Quinine intoxications reported to the Scottish Poisons Information Bureau 1997-2002: a continuing problem.

Quinine is widely prescribed in the UK for night cramps. Its potential toxicity in overdose is well known. We have reviewed the Scottish experience of enquiries regarding quinine overdose to the poisons information service responsible for Scotland over a 6-year period. Between 1997 and 2002 there were 96 reports of suspected quinine toxicity from Scotland (population 5.2 million), 19 of which were in children. The largest quantities of drug ingested were in patients between the ages of 11 and 30. In comparison with older studies the pattern of quinine poisoning does not appear to have changed in the UK over 20 years, despite recognition that it is a toxic agent in overdose, and particularly in children.

Chronic daily headache: II. Treatment

Volcy-Gomez M.
New England Center for Headache, Stamford, Connecticut 06902, USA. medvol98@yahoo.com
INTRODUCTION: The difficulty involved in treating chronic daily headache (CDH), a frequent pathology with a multifactorial aetiology, makes it a challenging disorder for clinicians. CDH is a disease that causes significant impact on patients, employers and the health system. DEVELOPMENT: The treatment of CDH is based on the implementation of three therapies. The first is to establish a pharmacological treatment, with medication such as antidepressants, antiepileptic agents, muscle relaxants, and antihypertensive and antiserotoninergic drugs, either in mono or in polytherapy. The second measure is to stop the analgesic overuse. This is achieved by suddenly withdrawing the drugs or, in a combined manner, by stopping the analgesic intake and establishing bridge therapy (steroids or triptans), which, in addition to reducing the severity and frequency of seizures and the consumption of drugs, also help to lower the occurrence and duration of withdrawal symptoms. Hospital treatment is needed in cases of patients who are refractory to multiple therapies, with frequent visits to the emergency department, in presence of associated symptoms or comorbidities, and low tolerance to medication. The third measure is to implement non-pharmacological therapies, which are used to modify inappropriate behaviour as regards pain treatment, to promote proper medication consumption and to allow the patient comprehend the prognosis of the disease with and without treatment. CONCLUSIONS: Implementing these three therapies makes possible to reduce the severity, frequency and socioeconomic impact caused by headache and thereby improve patients' quality of life and capabilities.