New phenotype of severe neonatal episodic laryngospasm due to a missense mutation in SCN4A: A case report and literature review

Severe neonatal episodic laryngospasm (SNEL) is an ion channel disease characterized by recurrent life-threatening myotonia of respiratory muscle due to mutations in the voltage-gated sodium channel genes. Here we reported a newborn manifested as paroxysmal cyanosis and limb myotonia after birth. The neonate also developed muscle hypertrophy and stunted growth during the follow-up. Whole exome sequencing confirmed c.2395G>A, p.Ala799Thr heterozygous mutation of SCN4A. Carbamazepine was found to be effective on treating the disease. This case expands our understanding of the phenotype resulting from SCN4Amutations. By summarizing the characteristics of reported 16 cases in SNEL,we found they were mainly in the p.G1306E mutation. The common symptoms were upper airway muscle stiffness and feeding difficulties during neonates.When grow up, most patients have different degrees of recurrent attacks of myotonia and progressed muscle hypertrophy. Some of them have athlete-like special faces but all showed myotonic discharge in eletromyogram.

Negative Pressure Pulmonary Edema: A Case Report

Negative pressure pulmonary edema is an uncommon complication of the extubation of theendotracheal tube. An increase in intrathoracic pressure and negative pressure of the lung causedby acute laryngeal spasm results from acute upper respiratory obstruction causing life-threateningpulmonary edema by alveolar-capillary damage is called negative pressure pulmonary edema. Wehere describe 28-years old female case the preoperative diagnosis of pelvic inflammatory diseaseundergoing exploratory laporoscopy caused negative pressure pulmonary edema while extubation.With the immediate treatment, the patient was discharged without any abnormalities.

Repeated Postanesthetic Laryngospasm in a Male Adult

Laryngospasm is a potential complication after general anesthesia that is universally dreaded because the failure to act swiftly and effectively could be fatal for the patient. This case report involves a morbidly obese male patient who received his first general anesthetic and experienced 4 episodes of laryngospasm within an hour after emergence. Laryngospasm occurs when the vocal cords adduct, closing the glottis, thereby preventing gas exchange in a spontaneously ventilating individual. This patient was able to physically indicate his impending glottic closure, thus warning his caregivers of the imminent airway emergency. He was safely intubated during the fourth episode and admitted to the intensive care unit for monitoring. After 2 days, the patient was extubated and recovered otherwise uneventfully. This case demonstrates the high level of vigilance required during all phases of anesthesia care.

[Negative pressure pulmonary edema following a cholecystectomy - A case report]

Negative pressure pulmonary edema (NPPE) or post-obstructive pulmonary edema (POPE) is a rare but a life threatening respiratory situation. The most frequent cause of NPPE is a post anesthetic laryngospasm. Edema is developed after relief of upper airway obstruction. Its incidence is 0.1 % of general anesthesia with tracheal intubation. We report this clinical case of a 28-year-old woman, who developed dyspnea followed by acute respiratory distress with unilateral pulmonary edema after extubation following general anesthesia for cholecystectomy under celioscopy. After elimination of any other cause, context, clinical and radiological characteristics, and the favorable evolution under oxygen and furosemide made it possible for us to link this acute respiratory distress to a NPPE whose pathophysiological causes and mechanisms are discussed.

Guideline for Monitoring and Management of Pediatric Patients Before, During, and After Sedation for Diagnostic and Therapeutic Procedures: Update 2016

The safe sedation of children for procedures requires a systematic approach that includes the following: no administration of sedating medication without the safety net of medical/dental supervision, careful presedation evaluation for underlying medical or surgical conditions that would place the child at increased risk from sedating medications, appropriate fasting for elective procedures and a balance between the depth of sedation and risk for those who are unable to fast because of the urgent nature of the procedure, a focused airway examination for large (kissing) tonsils or anatomic airway abnormalities that might increase thepotential for airway obstruction, a clear understanding of the medication's pharmacokinetic and pharmacodynamic effects and drug interactions, appropriate training and skills in airway management to allow rescue of the patient, age- and size-appropriate equipment for airway management and venous access, appropriate medications and reversal agents, sufficient numbers of staff to both carry out the procedure and monitor the patient, appropriate physiologic monitoring during and after the procedure, a properly equipped and staffed recovery area, recovery to the presedation level of consciousness before discharge from medical/dental supervision, and appropriate discharge instructions. This report was developed through a collaborative effort of the American Academy of Pediatrics and the American Academy of Pediatric Dentistry to offer pediatric providers updated information and guidance in delivering safe sedation to children.

Association of childhood high body mass index and sleep disordered breathing with perioperative laryngospasm

BACKGROUND

Childhood high body mass index (BMI) and sleep disordered breathing (SDB) are increasingly prevalent and both are associated with perioperative respiratory complications. Laryngospasm is one of the more serious respiratory complications with potentially devastating consequences. It is presently unclear whether high BMI and incident SDB in children significantly amplifies the risks of perioperative laryngospasm. This study examined the hypothesis that compared to controls; children with high BMI and SDB at the time of surgery have higher rates of perioperative laryngospasm.

METHODS

Children (6-18 yr) who underwent elective, non-cardiac operations at a tertiary care center were the subjects of this cross-sectional study. Rates of perioperative laryngospasm were compared between normal controls and children who were overweight/obese and had clinical history of SDB at the time of surgery. Stepwise logistic regression analysis was performed to identify independent predictors of perioperative laryngospasm (dependent variable) using high BMI/SDB as the primary predictor variable.

RESULTS

Among 642 children, those who were overweight/obese and had incident SDB (N = 197) were younger, and had higher indexes of central adiposity. Children with high BMI and SDB had 3.8 times higher unadjusted odds of developing intraoperative laryngospasm (OR = 3.8; 95% CI = 2.1-6.9, p < 0.001). After adjusting for several relevant covariates, the following factors were found to be independent predictors of perioperative laryngospasm: high BMI + SDB, male sex and increasing neck circumference.

CONCLUSION

High BMI and incident SDB in children is associated with increased rates of perioperative laryngospasm. The mechanism(s) underlying this propensity to laryngospasm deserve further elucidation.

[Nocturnal choking sensation]

There are many different types of sleep disorders. The majority of sleep-related breathing disorders can be attributed to sleep apnoea syndrome. Nocturnal choking sensation is a different symptom, for which we present two cases. Nocturnal choking sensation is a terrifying symptom for the patient and the diagnostic approach can be challenging. Aside from sleep choking syndrome, this symptom may appear with nocturnal laryngospasm, insular epilepsy and nocturnal gastro-oesophageal reflux. A thorough patient history and observation of the nocturnal event, sometimes supported by EEG findings, may provide the clue to the diagnosis. These kinds of nocturnal symptoms are best analyzed in a clinic specialized in both epilepsy and sleep disorders.

Stridor secondary to hypocalcemia in the elderly: an unusual presentation

Though hypocalcemic stridor is a well-recognized pediatric emergency, it has rarely been reported in the elderly, and hypocalcemia of nutritional origin presenting with stridor in this group has not previously been reported. We report an elderly patient who presented with stridor and intermittent sudden airway obstruction resulting from laryngospasm secondary to hypocalcemia of nutritional origin and we present a brief review of this life-threatening complication of hypocalcemia.

Odor Provocation Test for Laryngeal Hypersensitivity

This study was to present an odor provocation/challenge test for laryngeal hypersensitivity in a suspected odor induced dysphonic patient. The second aim was to rule out secondary gain from organic laryngeal hypersensitivity. Two steps were taken for this purpose. First, because the evaluation of hypersensitivity may be affected by the perception of odor, the study investigated laryngeal hypersensitivity during nasal and oral breathing separately to disentangle possible cognitive reactions to odors. Second, a healthy control (HC) participant was used with the identical testing protocol for nasal breathing to minimize unbiased results. The HC's response to nasal breathing of the odors showed no response to all the stimuli. The participant with possible secondary gain issues responded differently to the odors when presented nasally versus orally. Oral breathing showed less severe and less frequent laryngeal hypersensitive reactions. This suggests that laryngeal hypersensitivity was either due to the odor, cognitive information, sensory changes in olfaction leading to psychological conditioning, or for any possible secondary gain. Hence, it is difficult to indicate the precise reason (cause and effect) for the participant's laryngeal hypersensitivity; however, this study describes the first structured, controlled, repeatable, and randomized design to investigate odor induced laryngeal hypersensitivity and decipher possible secondary gain from true laryngeal hypersensitivity.

Sleep-related laryngospasm caused by gastroesophageal reflux

Gastroesophageal reflux is a suspected cause of sleep-related laryngospasm [Thurnheer R, Henz A, Knoblauch A. Sleep-related laryngospasm. Eur Respir J 1997;10:2084-6], but the relationship has not been directly documented by polysomnography (PSG). We report the case of an eight-year-old girl with asthma who was referred for evaluation of awakenings with respiratory distress. The description of her events included stridorous breathing suggestive of laryngospasm. A PSG was performed with esophageal pH monitoring, and during the recording pH dropped below four on nine occasions. Following two of the pH drops, acute respiratory distress with stridor was documented in video and audio recording, supporting a causal relationship between sleep-related gastroesophageal reflux and laryngospasm.

Negative pressure pulmonary edema: report of three cases and review of the literature

Pulmonary edema following the relief of an upper airway obstruction is an uncommon and unpredictable clinical entity. This unusual disease is actually attributed to pulmonary and hemodynamic changes engendered by high negative intrathoracic pressures during the state of obstructed respiration, such as laryngospasm, epiglottitis, laryngotracheal neoplasm, etc. In this article, we report three cases of negative pressure pulmonary edema (NPPE) developed after the operations of tracheotomy, adenoidectomy, and microlaryngeal surgery. The etiology, pathophysiology, diagnosis, management, and outcome of NPPE are also brought into further discussion.

Idiopathic laryngeal spasm: management and long-term outcome

Idiopathic laryngeal spasm (ILS) is an uncommon disorder characterised by brief episodes of stridor, occurring at any time. Subsequent outpatient ENT examination is normal. These episodes cause considerable anxiety for both patient and physician. Little is known about the initiating event(s) in this condition or the long-term outcome. Using a combination of telephone and postal questionnaires with case note review, we have reviewed a cohort of 21 patients with this diagnosis managed by the senior author over the last 15 years. None of the 19 patients who responded were worse; 13 (68%) described improvement or complete resolution of symptoms. ILS is difficult to classify in the spectrum of vocal cord disorders, but appears distinct to those previously described. The condition responds well to a conservative management approach of reassurance and counselling.

Cervical osteophytes: a cause of potentially life-threatening laryngeal spasms

✓ This 80-year-old woman presented with acute breathing difficulty during neck flexion when cyanosis also developed. The only potential causes were detected on cervical magnetic resonance imaging: two large anterior cervical osteophytes compressing the retropharyngeal space. Excision of these osteophytes resulted in resolution of the symptoms.

Recurrent episodes of intractable laryngospasm during dissociative sedation with intramuscular ketamine

We report 2 cases of dissociative sedation with intramuscular ketamine with recurrent episodes of laryngospasm that we were unable to ventilate with bag-mask ventilation, in 1 case leading to endotracheal intubation to protect the airway. Supplemental oxygen was given throughout the sedations, and ventilatory status was noninvasively monitored on a continuous basis, providing detailed and objective documentation of the patients' clinical status throughout the sedations. We were, therefore, able to rapidly assess and confirm apnea, laryngospasm, and airway dysfunction.

Sleep-related laryngospasm: a video-polysomnographic recording

We present a case of laryngospasm in a 12-year-old male who experienced sudden, nocturnal episodes of breathing difficulties and agitation. Apart from laryngospasm, the main differential diagnoses included frontal seizures, sleep-related choking syndrome, sleep asthma, sleep apnoea and REM sleep behaviour disorder. The video and the EEG recordings supported the diagnosis of laryngospasm. The pH-metry confirmed the existence of reflux. Its treatment successfully controlled the episodes. This case illustrates, with a typical video recording, this infrequent type of paroxysmal event with an important differential diagnosis.[Published with video sequences].

Laryngospasm: an underdiagnosed symptom of X-linked spinobulbar muscular atrophy

The authors reviewed the occurrence and concomitant factors of laryngospasm in X-linked spinobulbar muscular atrophy (Kennedy disease [KD]). Recurrent laryngospasm was observed in 47% of 49 patients with KD, but in only 2% of a control group of patients with early-stage ALS.

[Vocal cord dysfunction. An important differential diagnosis to bronchial asthma]

Vocal cord dysfunction (VCD) is described as a functional disorder of the vocal folds which leads to an intermittent, inspiratory 'paradoxical' glottal closure. We report on three women with frequent repetitive shortness of breath attacks caused by VCD. This was diagnosed by transnasal videofiberendoscopy, with glottal closure being seen during inspiration. Because of the different etiologies, one of the patients was treated with breathing and speech therapy, another received Omeprazol for laryngopharyngeal reflux, and the third was treated by intralaryngeal botulinum toxin injections. All three patients showed a reduction in attacks. Clinically, VCD seems to mimic asthma. However, with a thorough patient history and diagnostics, especially with transnasal laryngoscopy during a (triggered) attack, a precise diagnosis seems possible.

[Laryngospasm associated with anesthesia: diagnosis and management]

Securing the airway is the most important part of anesthesia safety. In clinical practice there is always the risk of encountering laryngospasm, which is defined as the occlusion of the glottis by the action of the intrinsic laryngeal muscles. Once laryngospasm occurs, it leads to acute desaturation and subsequent organ dysfunction. In spite of such a dramatic deterioration, however, there are no systematic reviews that include pathophysiology, clinical incidence, prevention and its treatment. In this paper, we have reviewed laryngospasm, according to the induction of anesthesia and emergence from it, methods for securing the airway using a tracheal tube or a laryngeal mask airway, and the timing of tracheal extubation. In addition, we have summarized a prompt diagnosis and adequate prevention and management of laryngospasm associated with anesthesia.

Spontaneous negative pressure changes: an unusual cause of noncardiogenic pulmonary edema

The principal physiologic mechanism underlying the formation of negative pressure pulmonary edema (NPPE) is thought to be the creation of excessive negative intrathoracic force from inspiration against a critical obstruction of the upper airway. The increased subatmospheric transpulmonary pressures result in transudation of fluid from the pulmonary capillaries to the interstitium and alveoli. The clinical picture is that of pulmonary edema. Aggressive diagnostic and therapeutic intervention can be avoided if the syndrome is recognized early. This report highlights the clinical features of NPPE and serves as a reminder to the clinician that although NPPE can cause significant morbidity, conservative supportive therapy typically results in a good outcome.

Inspiratory stridor in elite athletes

STUDY OBJECTIVES

Diagnosis and medical intervention for exercise-induced bronchospasm (EIB) are often based on self-reported symptoms, without spirometric confirmation. Inspiratory stridor (IS), a symptom of vocal cord dysfunction (VCD), is frequently mistaken for EIB wheeze. Athletes with exercise IS that spontaneously resolves on activity cessation are suspect for VCD and may not have EIB. This study estimated IS prevalence in elite athletes and determined its relationship to EIB.

SUBJECTS/METHODS

Three hundred seventy athletes (174 female and 196 male subjects) provided a medical history, and underwent spirometry before and after exercise challenge. Exercise challenges were conducted in cold, dry ambient conditions. EIB positive (EIB +) was defined as a > or = 10% postexercise fall in FEV(1). Athletes were monitored for IS during exercise; 78.4% of the athletes in this study (n = 290) were tested on multiple occasions.

RESULTS

EIB was identified in 30% of 370 athletes tested (58 female and 53 male subjects). IS was observed in 5.1% (18 female and 1 male subjects) during exercise and spontaneously resolved in these subjects within 5 min after exercise cessation. Ten IS-positive (IS +) athletes (52.6%) were EIB +, and 8 of these athletes had a previous EIB diagnosis; however, beta(2)-agonist treatment resolved IS in only 2 subjects. Eight of nine IS +/EIB-negative (EIB -) athletes had a previous EIB diagnosis; seven subjects received beta(2)-agonist treatment with no IS resolution. Resting spirometric measurements did not distinguish IS, but postexercise mid-flow (FEF(50)/FIF(50)) ratio > 1.5 was more frequent (33%, p < 0.05) among IS + athletes. The FEF(50)/FIF(50) ratio was higher for IS +/EIB + athletes than for IS -/EIB + athletes (1.97 +/- 1.69 vs 0.81 +/- 0.39, p < 0.05). The postexercise fall in FVC was greater (p < 0.05) for IS +/EIB - athletes (9.2 +/- 5.0%) than for IS-negative (IS -) /EIB - athletes (5.3 +/- 4.3%). No difference in postexercise FEV(1) was identified between IS + and IS - athletes (within EIB + or EIB - groups).

CONCLUSIONS

Five percent of athletes were IS +, with EIB comorbidity observed in 53% of these subjects. Misdiagnosis of IS as EIB is common. The lack of a beta(2)-agonist response in combination with postexercise serial spirometry can be useful in excluding solitary IS and confirming EIB diagnosis.

Review of laryngospasm and noncardiogenic pulmonary edema

Laryngospasm is an emergency situation that requires rapid identification and resolution of the obstructed glottis. Although there is a low incidence of laryngospasm, it is important to remember that any patient has the potential for post-extubation laryngospasm. Nurses must know about the causes, risk factors and treatment for this respiratory emergency. This includes the plan of care and possible medications administered to assist in restoring the patient's airway. Nurses must be able to respond quickly to avoid complications such as noncardiogenic pulmonary edema (NCPE) and respiratory arrest. The triggers, signs and symptoms, and treatment of NCPE are also reviewed. Due to the risk of laryngospasm recurring or NCPE presenting itself, any patient who has had laryngospasm needs close monitoring for two to three hours after the laryngospasm has resolved. It is important for nurses to review the interventions for laryngospasm and NCPE prior to caring for a patient with this respiratory emergency.

An overview of reflux-associated disorders in infants: apnea, laryngospasm, and aspiration

Problematic airway responses in infants are common. Reflux-induced apnea affects nearly 1% of infants and involves airway closure or laryngospasm. Recurrent or chronic stridor, caused by dynamic or structural airway abnormalities, occurs in up to 1 in 100 babies. It can be difficult to distinguish microaspiration, which may represent inadequate airway protection mechanisms, from reflexive responses to esophageal refluxate, which may represent overeffective airway protection mechanisms. The diagnosis of gastroesophageal reflux (GER) in babies can be facilitated by a careful history in conjunction with esophageal pH probe monitoring, laryngoscopic evaluation, bronchoalveolar lavage, or nuclear medicine scintigraphy. Conservative lifestyle measures for treating supraesophageal manifestations of infantile GER include prone positioning and thickened feedings. Prokinetic and acid-suppressing therapies are widely used, but their efficacy is incompletely established, and none is currently approved by the US Food and Drug Administration for this purpose. Fundoplication is not indicated if nonsurgical management can prevent serious problems during the child's maturation phase when many of these manifestations spontaneously resolve. Much remains to be learned about the developmental aspects of these supraesophageal manifestations of GER. This information not only will provide a greater understanding of developmental pathophysiology, but also will improve the clinical care of large numbers of infants.

The laryngeal mask and VBM laryngeal tube compared during spontaneous ventilation. A pilot study

BACKGROUND AND OBJECTIVE

The laryngeal tube is a variant of the oesophageal obturator airway. The manufacturer claims that it is an alternative to ventilation with a facemask, laryngeal mask or endotracheal tube. To date, published studies have only involved controlled ventilation. We wished to find out if its use in spontaneous ventilation was equivalent to using the laryngeal mask airway.

METHODS

We have compared the laryngeal tube with the laryngeal mask in a randomized prospective study involving patients breathing spontaneously under general anaesthesia. Criteria and a scoring system were used for the comparison. A sequential analysis chart with P=0.01 was chosen for each of two anaesthetists.

RESULTS

Only seven and 10 pairs of patients were required to indicate that the laryngeal tube was poorer at airway maintenance than the laryngeal mask. Of the 17 patients who had received the laryngeal tube, successful airway maintenance was only possible in seven. In the remaining 10 patients, the laryngeal tube was abandoned and the rescue airway was the laryngeal mask in all cases. All 17 patients randomized to the laryngeal mask were successfully managed.

CONCLUSIONS

We conclude that the laryngeal tube is not a satisfactory device for management of the airway during spontaneous ventilation.

Response of the cricothyroid and thyroarytenoid muscles to stereotactic injection of substance P into the region of the nucleus tractus solitarius in developing dogs

Substance P (SP), a putative sensory neurotransmitter, mediates reflex laryngeal adductor activity in developing dogs. Such reflex activity includes life-threatening laryngospasm induced by stimulation of distal esophageal afferent nerves. The site of SP's activity is unknown. This research was undertaken to determine whether injection of SP into the nucleus tractus solitarius (NTS) of developing beagles alters laryngeal adductor motor activity. Six animals, 57 to 78 days of age, underwent stereotactic injection of 5 to 10 microL of SP into the region of the NTS, identified by electrical stimulation of the ipsilateral superior laryngeal nerve. In 8 additional studies, SP was injected into the cerebellum (2) or brain stem (6) distant from the NTS. Cardiovascular and electromyographic (EMG) responses of the diaphragm and the cricothyroid (CT) and/or thyroarytenoid (TA) muscles were recorded in all 6 animals. Injection of SP into the region of the NTS induced a decrease in blood pressure in all animals and an increase in either ipsilateral CT or TA activity. Three of these animals experienced mixed apnea characterized by sustained EMG activity (spasm) of the ipsilateral CT or TA muscles and an absence of diaphragm EMG activity. The apnea event was fatal in 1 of these animals. In the 6 animals who underwent injections in the brain stem but outside the region of the NTS, diaphragm and laryngeal EMG activity generally did not change after injection of SP, with the exception of 1 animal who experienced a mild, short-lived increase in ipsilateral CT activity. A brief phasic increase in ipsilateral CT activity was seen in both animals who underwent injection of SP into the cerebellum. A putative sensory neurotransmitter, SP evokes ipsilateral CT and/or TA EMG activity when injected into the region of the NTS in developing beagle dogs. This research suggests that SP in the NTS may play a role in mediating life-threatening laryngeal adductor reflexes in developing mammals and may provide important information regarding therapeutic intervention.

Laryngeal electromyography: diagnostic and prognostic applications

Laryngeal electromyography is a crucial diagnostic test in laryngology. Laryngeal electromyography is important for the diagnosis of vocal fold paresis and cricoarytenoid joint pathology (e.g., arytenoid dislocation). In addition, laryngeal electromyography offers prognostic information regarding potential vocal fold paralysis recovery, which can improve the management strategies for vocal fold paralysis.

[Laryngeal spasm as a symptom of ventricular volvulus]

A male patient with laryngeal spasm as the only initial symptom of gastric volvulus is described. After gastric surgery the laryngeal spasms disappeared. A possible connection between laryngeal spasm and gastroesophageal acid reflux is discussed.

Nocturnal acute laryngospasm in children: a possible epileptic phenomenon

Respiratory difficulties are not uncommon during epileptic activity in all age groups. Laryngospasm, as an isolated manifestation of epileptic disorder, is a rare phenomenon described previously in only two patients. We report our experience with five children in whom nocturnal laryngospasm was the only clinical manifestation of their epileptic disorder. All children underwent extensive workup and the diagnosis was made by sleep-deprived electroencephalography (two cases) and sleep study (three cases). All patients were treated with carbamezapine with prompt resolution of their laryngospasm.

[Voice signal analysis in laryngeal hyperreactivity]

Increased reactions of the laryngeal mucosal membrane can appear after acetylcholine (ACH) inhalation. A red mucous membrane, vocal cord edema, mucus formation, changes in the glottic configuration and (rarely) subglottic edema are visible to laryngoscopic observations. The influence on various voice parameters in patients with and without laryngeal hyperreactivity was researched in order to decide the reliability of voice parameter measurements in clinical practice. Significant variations of the soft phonation index (SPI), the fundamental frequency variation (vFo), the noise-to-harmonic ratio (NHR) and the voice turbulence index (VTI) were examined for their correlations with the observable features of laryngeal hyperreactivity. A single diagnosis of hyperreactivity with voice parameter analysis failed in 50% of the patients examined because of functional voice instability and irregularities seen. Only with both laryngoscopy for reliable discrimination and voice parameter analysis for quantitative registration were findings sufficient for assessing laryngeal hyperreactivity.

Sleep-related laryngospasm

The term "sleep-related laryngospasm" refers to episodic, abrupt interruption of sleep accompanied by feelings of acute suffocation followed by stridor. The condition is included in the diagnostic and coding manual of the American Sleep Disorders Association (ASDA), but there are few references in the peer-reviewed literature. Our description of the distinct clinical picture associated with this condition is based on an analysis of the histories of a series of 10 patients. The patients and their families gave precise, uniform accounts of the dramatic attacks. Diagnostic work-up included pulmonary and gastroenterological assessment. All patients reported sudden awakening from sleep due to feelings of acute suffocation, accompanied by intense fear. Apnoea lasting 5-45 s was followed by stridor. Breathing returned to normal within minutes. Patients were left exhausted by the attacks. Nine of our 10 patients had evidence of gastro-oesophageal reflux and six responded to antireflux therapy. We conclude that the nocturnal choking attacks (and the occasional daytime attacks experienced by some of the patients) are caused by laryngospasm. The pathogenesis of the apparent underlying laryngeal irritability is unknown. The condition may be related to a gastro-oesophageal reflux.

Spasmodic laryngeal dyspnea: a rare manifestation of laryngeal dystonia

We describe clinical experiences in the management of three patients with laryngopharyngeal dystonia causing severe breathing problems. In contrast to spasmodic dysphonia, which presents with action-induced involuntary spasm of laryngeal muscles during speaking, all three patients showed laryngopharyngeal spasms primarily during respiration. In analogy to spasmodic dysphonia we propose the term spasmodic laryngeal dyspnea for this rare condition. Localized unilateral botulinum toxin injected into the thyroarytenoid muscle and/or ventricular folds reduced the quantity and quality of spasms and led to a pronounced improvement of breathing problems.

[Vocal cord dysfunction, an important differential diagnosis of severe and implausible bronchial asthma]

BACKGROUND

For asthmatics who show-despite of all available therapeutic efforts-an unsatisfactory clinical course in- or exspiratory vocal cord dysfunctions are an important diagnostic consideration. Aside from some case reports, there is only one major study, presenting a prevalence of > 30% in subjects admitted because of refractory asthma.

PATIENTS AND METHODS

The question was whether this phenomenon could also be found in our patients, mostly in- or extrinsic asthmatics. In cases suspicious for VCD or with an unexplainable asthma course, we performed videotaped laryngoscopy, including exposure to questionable provocing irritants.

RESULTS

In 14 months, we detected VCD in 16 patients by laryngoscopy and spirometry at the time of severe dyspnea. Subjects were predominantly women. Our therapeutical approach included: explanation of their videotape, speech therapy, breathing techniques and psychological support. In patients, pretreated with systemic corticosteroids, the dose could be reduced remarkably. A benefit 3 month after diagnosis could be shown using a life-quality-questionnaire.

CONCLUSIONS

Screening for VCD in patients with unplausible, refractory asthma and other unexplained dyspnea- or wheezing attacks is an important diagnostic consideration in order to prevent unnecessary medical treatment or drug related side-effects and to introduce a specific therapeutical concept.

Episodic paroxysmal laryngospasm: voice and pulmonary function assessment and management

Episodic paroxysmal laryngospasm (EPL) is a sign of laryngeal dysfunction, often without a specific organic etiology, which can masquerade as asthma, vocal fold paralysis, or a functional voice disorder. The intermittent respiratory distress of EPL may precipitate an apparent upper airway obstructive emergency, resulting in unnecessary endotracheal intubation, cardiopulmonary resuscitation, or tracheostomy. During 27 months, seven women and three men, age 30-76 years, were assessed by a high diagnostic index of suspicion, an intensive history including psychosocial factors, physical examination of the airways, provocative asthma testing, and swallowing studies. Videolaryngoscopy, stroboscopy, and pulmonary flow-volume loop testing were definitive. The classic appearance was paradoxic inspiratory adduction of the anterior vocal folds with a posterior diamond-shaped glottic gap. During an attack of stridor or wheezing, attenuation of the inspiratory flow rate as depicted by the flow-volume loop suggested partial extrathoracic upper airway obstruction. Swallowing evaluation by videolaryngoscopy and videosophagography may uncover gastroesophageal reflux disease. Hallmarks of management include patient and family education by observation of laryngoscopic videos, a specific speech therapy program, psychotherapy, and medical treatment of associated disorders. Electromyography may become a valuable future adjunct. Unlike laryngeal dystonia, patients with EPL do not benefit from botulinum toxin type A.

Sleep-related laryngospasm

Seven patients (mean age 46.6; range 33-58; 6M,1F) presented with sleep-related choking episodes and were found to have features in common that distinguished them from other known causes of choking episodes during sleep. The characteristic features include: an awakening from sleep with an acute choking sensation, stridor, panic, tachycardia, short duration of episode (less than 60 seconds), infrequent episodes (typically less than 1 per month), and absence of any known etiology. The disorder most commonly occurs in middle-aged males who are otherwise healthy. In one patient an episode of laryngospasm was polysomnographically documented to occur during stage 3. The clinical features and the polysomnographic findings suggest spasm of the vocal cords of unknown etiology.

[Not all wheezing is asthma: on functional laryngospasm]

Functional disturbances of the larynx can obstruct respiratory airflow resulting in dramatic states of dyspnoea or shortness of breath. Whereas in inspiratory functional laryngospasm the diagnosis is suggested by inspiratory stridor and hoarseness, it is often difficult to differentiate between the two expiratory forms, namely, laryngospasm in asthma and laryngeal pseudoasthma on the one hand, and an obstructive disease of the lower respiratory tract on the other. Seven case reports demonstrate the by no means uniform pattern of symptoms, the diagnostics and the unfortunately not always satisfactory possibilities of treatment. Pulmonary functional analysis and laryngoscopy are the most important diagnostic procedures in this regard. Even if it is not always possible to achieve the desired freedom from symptoms by means of respiratory therapy, logopaedics or psychotherapy, a correct diagnosis will nevertheless protect both the patient and the doctor against further useless attempts at drug treatment.

Functional laryngeal obstruction relieved by panting

A 49-year-old man presented with a two-day history of severe recurrent dyspnea and inspiratory stridor. A chest roentgenogram, computed tomographic scan of the neck, direct laryngoscopy, and bronchoscopy excluded organic upper airway obstruction. Laryngospasm occurred during the bronchoscopy. Although flow volume loops revealed severe upper airway obstruction (inspiratory and expiratory), airway resistance measured plethysmographically (during panting) was normal. Because of this observation, panting was recommended for relief of the patient's recurrent attacks of functional laryngeal obstruction. The panting maneuver immediately and completely relieved all 25 to 30 subsequent attacks. After the patient recovered clinically, a flow volume loop was repeated and was found to be normal. The marked discrepancy between severe flow limitation (as detected by flow volume loops) and normal airway resistance (measured plethysmographically) may be a diagnostic test for functional laryngeal obstruction, and panting may be an effective emergency measure for its relief. Relief by panting may also suggest the diagnosis. A second patient with an almost identical symptom complex is described, in whom the panting maneuver was also dramatically successful in promptly aborting recurrent severe attacks of airway obstruction and stridor.

Vocal cord dysfunction in a child with asthma

Vocal cord dysfunction is uncommon in children. We present the case of a 12-year-old boy with a history of mild, intermittent asthma from 7 to 10 years of age. Subsequently, severe, rapid-onset attacks of respiratory distress occurred with increasing frequency. After a life-threatening attack of airway obstruction with 3 minutes of apnea, he was hospitalized for diagnostic studies. Although pulmonary function tests were normal, laryngoscopy under general anesthesia revealed extremely severe vocal cord spasm induced by minimal contact of the laryngoscope. It required intravenous lidocaine and muscle relaxant to reverse. Spasm was not demonstrable one week later on repeat laryngoscopy and bronchoscopy. No structural abnormalities were seen. There was considerable family stress exacerbated by anxiety about the patient's illness. Parents were told that the condition was different from asthma and probably functional in origin. There have been no further episodes, possibly due to counseling and education in relaxation techniques as well as oral pharmacotherapy for asthma with avoidance of inhaled medications.

[Laryngitis epidemic (893 cases of acute laryngotracheitis and spastic croup). II. Clinical, diagnostic and therapeutic aspects]

We retrospectively review 893 cases of children, occurred in epidemic bout in September-October 1987, in order to study the usual management of his pathology in our hospital. In most cases (82.3%) diagnose was laryngitis or acute laryngitis without specification acute laryngotracheitis or spasmodic group. Epiglottitis was no detected in any case. Complementary tests were performed only in 5% of the patients, but they were of little help for the diagnose. Treatment applied was ambiental hummidiffication (95.5%), followed by water and alcohol impregned neck collar (87.2%), rectal magnesium-sulfate + papaverine (67.5%), epinephrine nebulization (63%), antibiotics (44.3%), steroids (9%), bronchodilatadors (4.8%). This therapeutic approach is discussed.