Positional Maneuvers Research Articles

Akutes Lungenversagen - Therapeutische Optionen im Überblick

The treatment of acute lung injury is one of the most challenging tasks in intensive care medicine. Conventional therapeutic options cover lung protective mechanical ventilation with low tidal volumes and adequate PEEP, restrictive fluid management, prone positioning, and early recruitment maneuvers. These options should be used in parallel and should be accompanied by a suitable anti-infective therapy. In cases of refractory hypoxemia, inhaled nitric oxide offers in most patients a successful rescue option. In specialized centers the application of ECMO remains as a final ultima ratio.

Autonomic function testing in children and adolescents with diabetes mellitus

Cardiac autonomic neuropathy (CAN) is a common complication in type 1 diabetes mellitus (T1DM) and associated with an increased mortality. Early detection of CAN would be desirable for a better individual risk stratification. The aim of this study was to determine whether autonomic dysfunction can be diagnosed in young patients with a recent history of T1DM. Autonomic function was assessed in 20 pediatric patients with T1DM, aged 10-19 yr, and a control group of 136 non-diabetic patients using four cardiorespiratory reflexes: heart rate and blood pressure response in standing position, deep breathing, and Valsalva maneuver. Furthermore, power spectral analyses of the low- and high-frequency band of heart rate variability (HRV) and baroreflex sensitivity (BRS) were tested with the non-invasive Task force monitor (CNSystems, Graz, Austria). Cardiorespiratory reflexes were pathologic for at least one item in 75% of the diabetic and 60% in the healthy control group. A reduced BRS was always combined with abnormal HRV. We found this pattern in 30% of diabetic patients and never in the control group. In patients with impaired BRS, mean hemoglobin A1c (HbA1c) was 7.7% and duration of diabetes 6.5 yr. This did not differ from the overall value of the diabetic group: HbA1c level 8.4% and diabetes duration 7.3 yr. In conclusion, signs of autonomic dysfunction are not uncommon in an early stage of diabetes in young patients. Classical cardiorespiratory reflexes seem to be less specific than HRV and BRS as testing methods.

Horizontal and anterior canal benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is suspected when the patient complains of brief episodes of vertigo induced by changes in the head position. The direction of the positional nystagmus during the positional maneuvers is essential to affirm the canal involved. There is a consensus for the diagnosis of a PC-BPPV and HC-BPPV (geotropic and ageotropic form) as well as for the treatment of a PC-BPPV and a geotropic HC-BPPC. However, there is still a debate for the diagnosis of an AC-BPPV and the treatment of an ageotropic HC-BPPV and an AC-BPPV.

Response to Letter by Johkura

HomeStrokeVol. 38, No. 6Response to Letter by Johkura Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBResponse to Letter by Johkura Kevin A. Kerber Lewis B. Morgenstern Kevin A. KerberKevin A. Kerber Departments of Neurology and Otolaryngology, University of Michigan Health System, Ann Arbor, Mich Search for more papers by this author Lewis B. MorgensternLewis B. Morgenstern Stroke Program, University of Michigan Health System, Ann Arbor, Mich, Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, Mich Search for more papers by this author Originally published19 Apr 2007https://doi.org/10.1161/STROKEAHA.106.481119Stroke. 2007;38:e28Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: April 19, 2007: Previous Version 1 Response:We thank Dr Johkura for his interest in our recent study. We agree that distinguishing a central from a peripheral cause of dizziness in an individual patient can be challenging. A recent study demonstrates well that cerebellar infarction can closely mimic vestibular neuritis.1 These type of studies1–3 indicate that if one relies on isolated dizziness to discriminate, some patients with potentially serious etiologies will be missed. However, these studies also show that stroke is a very rare cause of isolated dizziness, so a call for increasing use of neuroimaging in the dizzy patient in general does not seem justifiable, particularly when considering the healthcare utilization perspective.In his correspondence, Dr Johkura stresses difficulty in distinguishing central from peripheral causes of positional vertigo. Benign paroxysmal positional vertigo (BPPV) is generally readily distinguishable from central positional vertigo based on bedside characteristics of nystagmus and also the response to the simple repositioning maneuver described by Epley 15 years ago.4 Repositioning maneuvers for the horizontal canal variant are also well described.5 The patterns of nystagmus caused by BPPV are highly characteristic and well-defined for this very common disorder and its variants.6 To be conservative, central positional vertigo should be considered when features of BPPV are atypical or when nystagmus continues to be triggered by positional testing despite repositioning maneuvers. The extra step of retesting is critical to ensuring that the maneuvers did correct the disorder because repositioning does not treat central positional vertigo. Dr Johkura’s study helps to reiterate how uncommon central causes of positional vertigo are compared with BPPV. Because CT scans can miss a tumor or ischemic stroke, particularly within the posterior fossa, and MRI is not a practical routine study for the common presentation of dizziness in the Emergency Department, we feel a greater understanding of dizziness among clinicians and more studies establishing clinical predictors of central causes should be emphasized rather than increased reliance on neuroimaging.Sources of FundingL.B.M. is supported by NIH R01 NS38916.DisclosuresNone.1 Lee H, Sohn SI, Cho YW, Lee SR, Ahn BH, Park BR, Baloh RW. Cerebellar infarction presenting isolated vertigo: frequency and vascular topographical patterns. Neurology. 2006; 67: 1178–1183.CrossrefMedlineGoogle Scholar2 Kerber KA, Brown DL, Lisabeth LD, Smith MA, Morgenstern LB. Stroke among patients with dizziness, vertigo, and imbalance in the emergency department: a population-based study. Stroke. 2006; 37: 2484–2487.LinkGoogle Scholar3 Johkura K. Vertigo and dizziness associated with cerebrovascular diseases. Nihon Ishikai Zasshi [The Journal of the Japan Medical Association]. 2005; 134: 1485–1490[In Japanese].Google Scholar4 Epley JM. The canalith repositioning procedure: for treatment of benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg. 1992; 107: 399–404.CrossrefMedlineGoogle Scholar5 Lempert T, Tiel-Wilck K. A positional maneuver for treatment of horizontal-canal benign positional vertigo. Laryngoscope. 1996; 106: 476–478.CrossrefMedlineGoogle Scholar6 Aw ST, Todd MJ, Aw GE, McGarvie LA, Halmagyi GM. Benign positional nystagmus: a study of its three-dimensional spatio-temporal characteristics. Neurology. 2005; 64: 1897–1905.CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetails June 2007Vol 38, Issue 6 Advertisement Article InformationMetrics https://doi.org/10.1161/STROKEAHA.106.481119 Originally publishedApril 19, 2007 PDF download Advertisement

Epidemiology of vertigo

Epidemiological findings on the distribution, determinants and outcome of vertigo can be used for clinical decision making and can help understand the underlying causes of vestibular diseases. This article gives an overview of the epidemiology of the vestibular symptom vertigo and of four specific vestibular disorders: benign paroxysmal positional vertigo, migrainous vertigo, Menière's disease and vestibular neuritis. Based on a neurotologic survey of the general population, 1-year prevalence estimates for vertigo were 4.9%, for migrainous vertigo 0.89% and for benign paroxysmal positional vertigo 1.6%. Diagnostic positional manoeuvres and treatments for benign paroxysmal positional vertigo, however, are still not being done by most doctors. The female preponderance among patients with benign paroxysmal positional vertigo and migrainous vertigo may be linked to migraine but is not fully understood. A recently reported prevalence of Menière's disease of 0.51% is much higher than previous estimates. Follow-up studies have shown benign paroxysmal positional vertigo recurrence rates of 50% at 5 years and a persistence of dizziness related to anxiety in almost a third of patients 1 year after vestibular neuritis. The epidemiology of vertigo and vestibular disorders is still an underdeveloped field. Recent studies have underscored the impact of vertigo at the population level, but its determinants and outcome are not well known yet.

Vertebral height restoration in osteoporotic compression fractures: kyphoplasty balloon tamp is superior to postural correction alone

Kyphoplasty has been shown to restore vertebral height and sagittal alignment. Proponents of vertebroplasty have recently demonstrated that many vertebral compression fractures (VCFs) are mobile and positional correction can lead to clinically significant height restoration. The current investigation tested the hypothesis that positional maneuvers do not achieve the same degree of vertebral height correction as kyphoplasty balloon tamps for the reduction of low-energy VCFs. Twenty-five consecutive patients with a total of 43 osteoporotic VCFs were entered into a prospective analysis. Each patient was sequentially evaluated for postural and balloon vertebral fracture reduction. Preoperative standing and lateral radiographs of the fractured vertebrae were compared with prone cross-table lateral radiographs with the patient in a hyper-extension position and on pelvic and sternal rolls. Following positional manipulation, patients underwent a unilateral balloon kyphoplasty. Postoperative standing radiographs were evaluated for the percentage of height restoration related to positioning and balloon kyphoplasty. In the middle portion of the vertebrae, the percentage available for restoration restored with extension positioning was 10.4% (median 11.1%) and after balloon kyphoplasty was 57.0% (median 62.2%). This difference was statistically significant (p<0.001). Thus, kyphoplasty provided an additional 46.6% of the height available for restoration from the positioning alone. With operative positioning, 51.2% of VCFs had >10% restoration of the central portion of the vertebral body, whereas 90.7% of fractures improved at least 10% following balloon kyphoplasty (p<0.002). Although this study supports the concept that many VCFs can be moved with positioning, balloon kyphoplasty enhanced the height reduction >4.5-fold over the positioning maneuver alone and accounted for over 80% of the ultimate reduction. If height restoration is the goal, kyphoplasty is clearly superior in most cases to the positioning maneuver alone.

Prospective Study of Positional Nystagmus in 100 Consecutive Patients

The purpose of this study was to investigate the various diagnoses of patients who present with positional nystagmus. Positional maneuvers were systematically performed in the plane of the posterior canal (PC; Dix-Hallpike maneuver) and the horizontal canal (HC; patients were rolled to either side in a supine position) on 490 consecutive patients essentially referred for vertigo and/or gait unsteadiness. One hundred patients (20%) presented positional nystagmus. This nystagmus had a peripheral origin in 83 patients, including 80 patients with benign paroxysmal positional vertigo (BPPV). In BPPV, the PC was involved in 61 patients, the HC in 18 patients (geotropic horizontal nystagmus in 11 and ageotropic in 7; changing from geotropic to ageotropic or the reverse in 4 patients), and both the PC and HC in 1 patient. There was evidence of central positional nystagmus in 12 patients, including positional downbeat nystagmus during the Dix-Hallpike maneuver in 7 patients with various neurologic disorders, and ageotropic horizontal nystagmus during the HC maneuver in 2 patients with, respectively, cerebellar ischemia and definite migrainous vertigo. The peripheral or central origin of the positional nystagmus could not be ascertained in 5 patients, including 1 patient with probable migrainous vertigo and another with possible anterior canal BPPV. A rotatory-upbeat nystagmus in the context of PC BPPV, a horizontal nystagmus, whether geotropic or ageotropic, due to HC BPPV, and a positional downbeat nystagmus related to various central disorders are the 3 most common types of positional nystagmus. Geotropic horizontal positional nystagmus and, most certainly, horizontal positional nystagmus changing from geotropic to ageotropic or the reverse point to HC BPPV. In contrast, an ageotropic horizontal positional nystagmus that is not changing (from ageotropic to geotropic) may indicate a central lesion.

Eine schonende Methode zur Reposition der vorderen Schulterluxation

Acute shoulder dislocation is a common injury and characterized by an extremely painful lack of motion. The treatment objective after diagnosis is immediate reduction avoiding additional pain and complications. Various techniques have been described for more than 2000 years mostly using traction-countertraction, particularly combined with special positioning and leverage maneuvers. We report a reduction technique which is performed by a single person with the patient sitting on a chair and the physician standing behind him at the affected side. Positioning one fist in the anterior part of the axillary fossa for countertraction but avoiding direct pressure into the axillary fossa, the other hand uses traction grasping the patient's forearm. Only gentle traction is maintained until muscle relaxation is achieved and reduction mostly happens in this moment. Otherwise slow external rotation of the fist placed in the axilla can relieve reduction pushing the humeral head laterally. Additional leverage maneuvers are not necessary. This technique was successful in 98 of 108 (90.7%) patients. Only in 16.3% was premedication (intravenous analgesics) used. In ten patients general anesthesia was required to achieve reduction. No complications occurred in any of the patients. The reported technique allows a gentle and painless reduction of acute anterior shoulder dislocation with a high success rate mostly avoiding premedication.

A Positional Maneuver to Augment Conventional Cholescintigraphy in the Evaluation of Acute Acalculous Cholecystitis

Abstract:Cholescintigraphy is commonly used as an accurate functional complement to anatomic imaging for diagnosing acute calculous cholecystitis. Although less common, acute acalculous cholecystitis (AAC) can also cause right upper quadrant pain, especially in hospitalized and critically ill patien

Arterial complications of thoracic outlet syndrome

Objective: Arterial vascular complications resulting from thoracic outlet compression, although rare, can be substantial and potentially limb threatening. These complications are due to compressions at the thoracic outlet, the treatment of which continues to be a dilemma. The objective of the present study was to review our experience with this problem with particular reference to its management.Methods: We performed a retrospective study of 12 years and retrieved data from the medical records department of Nizam’s Institute of Medical Sciences, Hyderabad, India. A retrospective review identified 35 patients (age range 15–50 years). In 31 patients, the vasculopathy was caused by a cervical rib, soft tissue anomalies (n = 31), and an elongated transverse process (n = 4). Evaluation included assessment with colour duplex and arteriography with positional maneuvers. Thirty‐two patients presented with a fixed pulse deficit, 22 patients had palpable mass and 15 patients had distal embolization.Results: In 31 patients with cervical rib, the rib was excised via a supraclavicular approach, Scalenectomy was performed and the arterial pathology was repaired on its merit, usually by a vein graft replacement or bypass. The elongated process was excised in the other four patients. Twelve patients required thrombectomy of the distal arteries and a bypass procedure (with a vein/prosthetic graft) was performed in 14 patients. Dorsal sympathectomy, as an adjunct, was carried out in 10 patients. In view of their advanced distal disease, four patients were given prostaglandin therapy. Short‐term follow up of 2 years showed good results.Conclusion: Our results show that simple excision of the cervical rib with scalenectomy via supraclavicular approach, together with arterial reconstruction (if required) is adequate for arterial vascular complications resulting from thoracic outlet compression. Patients with severe distal disease may require other adjunct procedures like dorsal sympathectomy or prostaglandin infusions along with proximal reconstruction.

Office and Home Maneuvers for Benign Positional Vertigo

Positional maneuvers to treat benign paroxysmal positional vertigo (BPPV) can be performed in the clinician's office or at home. This randomized trial

Opening the upper airway – airway maneuvers in pediatric anesthesia

Maintenance of a patent airway is the most important aspect of the safe administration of anesthesia in children. However, in spontaneously breathing, anesthetized children, upper airway obstruction is a frequent problem (1) and failure to maintain a patent airway can rapidly result in hypoxemia, bradycardia or even cardiac arrest. Upper airway narrowing is most likely to appear in pharyngeal structures (2–4). Since the entire airway is composed of soft tissue and is kept patent during inspiration by the dilating action of the pharyngeal airway muscles, any drug that leads to a reduction of muscle activity can reduce airway patency and thus increase upper airway resistance (5). Children are particularly susceptible to upper airway obstruction because of the smaller dimensions of their airways and the high incidence of tonsillar and/or adenoidal hypertrophy which causes increased resistance to flow (6). During anesthesia and basic life support, positioning of body, head and neck as well as airway maneuvers such as jaw thrust and chin lift are commonly used to improve the patency of an obstructed or partially obstructed upper airway (7, 8). The importance of these maneuvers has been known for a long time; Jacob Heiberg wrote in 1874 that during chloroform anesthesia, noisy, obstructed breathing, particularly during inspiration, can be prevented by pulling the jaw forward (9), while other authors have even earlier advocated opening obstructed airways by pulling the tongue forward (10–12). This review focuses on the mechanisms and efficacy of different, simple methods to open and maintain a patent airway in spontaneously breathing children undergoing anesthesia, which include body, head and neck positioning and airway maneuvers such as mouth opening, chin lift, jaw thrust or the use of continuous positive airway pressure (CPAP).

Combined Horizontal and Posterior Canal Benign Paroxysmal Positional Vertigo in Three Patients with Head Trauma

We report 3 patients who complained of positional vertigo shortly after head trauma. Positional maneuvers performed in the plane of the posterior canal (PC; Dix-Hallpike maneuver) and the horizontal canal (HC; patients were rolled to either side in a supine position with the head raised 30 degrees) revealed a complex positional nystagmus that could only be interpreted as the result of combined PC and HC benign paroxysmal positional vertigo (BPPV). Two patients had a right PC BPPV and an ageotropic HC BPPV, and 1 patient had a bilateral PC BPPV and a left geotropic HC BPPV. All 3 patients were rapidly free of vertigo after the PC BPPV was cured by the Epley maneuver and the geotropic HC BPPV was cured by the Vannucchi method. The ageotropic HC BPPV resolved spontaneously. Neuroimaging (brain computed tomography and/or magnetic resonance imaging scans) findings were normal in all 3 patients. From a physiopathological viewpoint, it is easy to conceive that head trauma could throw otoconial debris into different canals of each labyrinth and be responsible for these combined forms of BPPV. Consequently, in trauma patients with vertigo, it is mandatory to perform the Dix-Hallpike maneuver, as well as supine lateral head turns, in order to diagnose PC BPPV, HC BPPV, or the association of both. Early diagnosis and treatment of BPPV may help to reduce the postconcussion syndrome.

수평반고리관 Cupulolithiasis에 의한 양성 돌발성 체위변환성 어지러움증으로 오인된 소뇌경색 1예

Benign Paroxysmal Positional Vertigo (BPPV) is the most common peripheral vestibular disorder. It can be diagnosed with characteristic symptoms and the nystagmus evoked by the positional change. We report a case of cerebellar infarction misdiagnosed as BPPV. A 58 years-old man, complaining rotatory positional vertigo for 3 days, visited our OPD. A head positional test was performed. and it induced positional ageotrophic nystagmus. He showed no neurologic abnormality in neurologic examination. We diagnosed his illness as cupulolithiasis of horizontal canal, so the cupulolith repositioning maneuver, applying vibrator on mastoid tip and forced prolonged position maneuver were performed. Then, the vertigo and the intensity of nystagmus were improved. Four days later, however, vertigo was aggrevated again showing same nystagmus. So we recommended magnetic resonance imaging, and multiple cerebellar infarctions were found. Even if patient shows typical nystagmus of BPPV, the neuroradiologic study should be conducted to rule out central lesion, in the case of no response to repositioning maneuver or reaggrevation. (J Clinical Otolaryngol 2004;15:311-315)

Medical management of patients with benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder which can be simply diagnosed. The evolution of highly effective positioning maneuvers has made BPPV the most successfully treatable cause of vertigo. We evaluated patients with BPPV with regard to past medical history and disease-related diagnostic and therapeutic procedures. Forty-two patients were recruited from a specialised dizziness clinic, and a further 29 patients were recruited from a neurological practice. The mean duration of the disease was 3.2 years, with an average of 2.4 episodes lasting typically several weeks to months. More than half of the patients felt severely disabled by BPPV. On average, three different medical specialities were consulted. Cerebral imaging (42%), caloric testing (46%), and audiometry (49%) were performed more often than diagnostic positioning (28%). Most patients received ineffective or no therapy, and only 4% were treated with a specific therapeutic positioning maneuver. Benign paroxysmal positional vertigo is a long-lasting and frequently recurrent disease which leads to significant morbidity and medical costs. The recent progress in the diagnosis and therapy of BPPV has not yet been widely established in medical practice in Germany.

Posición prono en síndrome de distress respiratorio agudo

Objective: To review and discuss the prone position manoeuvre in ARDS as a strategy of lung protection. Method: A computerized search in MEDLINE of all publicated articles of prone position in ARDS in children and adults was performed. We analyzed mechanisms of action, indications and timing of use, characteristics of the response, positioning manoeuvres, contraindications and complications. Results: An increase in the effective transpulmonary pressure, which is believed to be an important mechanism of alveolar recruitment, is one of the most important factors in the improvement of systemic oxygenation. In the paedriatric series about 80% of patients presented a positive response to the prone position with an improvement of oxygenation, occurring early and being sustained with time. We found differences in the timing of initiation of the prone position, as well as its duration and frequency. The evidence suggests that the optimum response is most likely to occur during early ARDS. Major iatrogenic complications are limited. Conclusions: Prone positioning is a manoeuvre with a biological rational to its use. It is an easy and harmless therapeutic intervention in order top improve systemic oxygenation and a reduction in mechanical ventilation parameters in ARDS patients.

Standard acid reflux testing revisited.

Patients who present with uncontrolled esophageal acid reflux symptoms require endoscopy to determine the presence or absence of ulcers and stenoses, acid reflux testing to determine if acid reflux is present, and manometry to evaluate esophageal peristalsis and spastic states. These studies are usually done in stages, at separate times. Esophageal manometry catheters currently in use have an incorporated infusion channel. This allows instillation of a dilute acid meal after esophageal manometry has been completed. Standard acid reflux testing can then be done using dynamic positioning and physiologic maneuvers. When combined with an esophagogastroduodenas copy (EGD), these three studies provide all information necessary within 2-3 h to determine further treatment of these patients. A total of 210 patients underwent these studies. A hiatus hernia was present in 84%. An ineffective lower esophageal sphincter was found in 64%. Esophageal hypocontractility was present in 18%, hypercontractility in 14%, and dysmotility in 36%. Upper esophageal sphincter was weak in 42%, hypercontractile in 42%, and dysmotile in 32%. Acid reflux disease was found in the hiatus hernia in 14% and acid reflux to the level of the lower esophagus in 16%, middle esophagus in 13%, and upper esophagus in 40%. Distal esophagitis was present in 47%, esophageal ulceration in 29%, gastric prolapse in 11%, gastritis in 52%, bile reflux disease in 10%, and Barrett's epithelium in 5%. In conclusion, an extremely high number of patients with esophageal acid reflux disease show dysmotility patterns. Standard acid reflux testing using dynamic positioning will identify most patients with significant acid reflux disease. When combined with an EGD, complete testing for acid reflux disease can be performed at one setting. Further study is needed comparing dynamic acid reflux testing to 24-h pH testing.

Oxygenation response to a recruitment maneuver during supine and prone positions in an oleic acid-induced lung injury model.

Prone position and recruitment maneuvers (RM) are proposed as adjuncts to mechanical ventilation to open up the lung and keep it open. We studied the oxygenation response to a RM (composed of a 30-s sustained inflation at 60 cm H(2)O airway pressure) performed in prone and supine positions in dogs after oleic acid- induced lung injury using an inspired O(2) fraction of 0.60. In one group (n = 6) first supine then prone positions were examined after a RM at 8 cm H(2)O and 15 cm H(2)O of positive end-expiratory pressure (PEEP). In the second group (n = 6) the sequence of positions was reversed. Prone positioning after supine position always improved oxygenation, whereas the decrement in Pa(O(2)) was relatively small when dogs were returned to the supine position. Oxygenation improved in both groups after a RM, and the improvement was sustained (after 15 min) in the prone position at 8 cm H(2)O of PEEP, but 15 cm H(2)O of PEEP was required in supine position. Our results suggest that a RM improves oxygenation more effectively with a decreased PEEP requirement for the preservation of the oxygenation response in prone compared with supine position.

Sliding mode rest-to-rest stabilization and trajectory tracking for a discretized flexible joint manipulator

In this article, a difference flatness approach is used for trajectory tracking tasks of an approximately (Euler) discretized model of a nonlinear, single link, flexible joint manipulator. The system's flat output is commanded to follow a prescribed trajectory achieving a desired angular position maneuver. A new robust discrete time feedback controller design technique, of the sliding mode type, is then proposed for the closed loop regulation of the link position around the prescribed trajectory. The effectiveness of the approach is illustrated by means of digital computer simulations in a rest-to-rest stabilization maneuver and in a sinusoidal reference trajectory tracking task.

A comparison of the cuffed oropharyngeal airway (COPA) with the laryngeal mask airway (LMA) during manually controlled positive pressure ventilation

Study Objective: To examine the cuffed oropharyngeal airway (COPA) during positive pressure ventilation (PPV) and to compare its reliability and efficacy with the laryngeal mask airway (LMA).Design: Prospective, randomized, controlled trial.Setting: University Hospital.Patients: 60 adult ASA physical status I and II patients scheduled for urologic surgery.Interventions: Patients were randomly assigned to be ventilated with a COPA (n = 33) or a LMA (n = 27) during a standardized anesthetic procedure. Following preoxygenation and induction with alfentanil and propofol, the respective airways were inserted. Patients were ventilated manually with the reservoir bag of the anesthesia respirator. Inspiratory airway pressure was limited to 20 cm H2O, and the target tidal volume was 7 ml/kg. Respiratory rate was adjusted to achieve an end-tidal pressure of carbon dioxide of 35 mmHg. Anesthesia was maintained with propofol, nitrous oxide in oxygen, and alfentanil, as appropriate.Measurements and Main Results: We evaluated ease of insertion (nominal scale: easy, moderate, difficult, or impossible) and recorded the number of maneuvers performed during insertion until an airtight seal of the airway was achieved. Reliability for “hands free” ventilation—defined as ventilation without the need to further augment the position of the airway device manually—was determined (nominal scale: adequate ventilation, adequate ventilation with manual assistance, and inadequate ventilation leading to airway change). Ventilation and oxygenation parameters were derived from the anesthesia respirator and a capillary blood gas sample, respectively. The incidence of laryngopharyngeal discomfort and the amount of salivation were assessed by nominal scales. The COPA was easier to insert than the LMA (p < 0.001), but more positional maneuvers (p < 0.001) were necessary with this device. “Hands free” ventilation was achieved less often with the COPA (p < 0.02). Ventilation and oxygenation were comparable with both devices. The COPA was associated with less salivation (p < 0.01) and laryngopharyngeal discomfort (p < 0.05) than the LMA.Conclusion: Although effective ventilation can be accomplished with both devices, the LMA is more reliable for “hands free” ventilation than the COPA. The lower incidence of laryngopharyngeal discomfort and salivation with the COPA may be beneficial for patients at risk for developing laryngospasm.