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Cuff Pressures (cuff + pressure)
Selected AbstractsCuff compliance of pediatric and adult cuffed tracheal tubes: an experimental studyPEDIATRIC ANESTHESIA, Issue 8 2004J.-M. Devys MD Summary Background :,Tracheal mucosal damage related to tracheal intubation has been widely described in pediatric and adult patients. High volume,low pressure cuffs (HVLPC) are being advertised as safe to avoid this particularly unpleasant complication. Compliances of these supposed pediatric and adult HVLPC are not mentioned by manufacturers and still remain unknown. Methods :,The compliance of HVLPC was measured in vitro and defined as the straight portion of the pressure,volume curve. Cuff pressure was measured after incremental 0.1 ml filling volumes of air for sizes 3.0,8.0 of internal diameter of RüschTM and MallinckrodtTM tracheal tubes. Compliances were assessed in air and in a rigid tube. The filling volume to achieve a 25-mmHg intracuff pressure was also measured. Results :,In air, each 0.1 ml step almost linearly increased cuff pressure by 1 mmHg (size 8.0) to 9 mmHg (size 3). In air, the volume needed to maintain a cuff pressure < 25 mmHg was small for sizes 3,5.5 (0.35,2 ml). The 25 mmHg inflated cuff volume and compliance were decreased within a rigid tube, especially for adult sizes. In a rigid tube simulating a trachea, the compliances of almost every RüschTM tracheal tube were statistically higher than those of the MallinckrodtTM. Conclusion :,We conclude that the tested tracheal tube cuffs have low compliance and cannot be defined as high volume,low pressure. [source] Vocal Fold Paralysis After Anterior Cervical Spine Surgery: Incidence, Mechanism, and Prevention of Injury,THE LARYNGOSCOPE, Issue 9 2000Mark D. Kriskovich MD Abstract Objective Vocal fold paralysis is the most common otolaryngological complication after anterior cervical spine surgery (ACSS). However, the frequency and etiology of this injury are not clearly defined. This study was performed to establish the incidence and mechanism of vocal fold paralysis in ACSS and to determine whether controlling for endotracheal tube/laryngeal wall interactions induced by the cervical retraction system could decrease the rate of paralysis. Study Design Retrospective review and complementary cadaver dissection. Methods Data gathered on 900 consecutive patients undergoing ACSS were reviewed for complications and procedural risk factors. After the first 250 cases an intervention consisting of monitoring of endotracheal tube cuff pressure and release of pressure after retractor placement or repositioning was employed. This allowed the endotracheal tube to re-center within the larynx. In addition, anterior approaches to the cervical spine were performed on fresh, intubated cadavers and studied with videofluoroscopy following retractor placement. Results Thirty cases of vocal fold paralysis consistent with recurrent laryngeal nerve injury were identified with three patients having permanent paralysis. With this technique temporary paralysis rates decreased from 6.4% to 1.69% (P = .0002). The cadaver studies confirmed that the retractor displaced the larynx against the shaft of the endotracheal tube with impingement on the vulnerable intralaryngeal segment of the recurrent laryngeal nerve. Conclusion The study results suggest that the most common cause of vocal fold paralysis after anterior cervical spine surgery is compression of the recurrent laryngeal nerve within the endolarynx. Endotracheal tube cuff pressure monitoring and release after retractor placement may prevent injury to the recurrent laryngeal nerve during anterior cervical spine surgery. [source] The effect of pilot balloon design on estimation of safe tracheal tube cuff pressureANAESTHESIA, Issue 8 2010K. M. Janossy Summary We studied the effect of pilot balloon design on the ability of experienced anaesthetists to assess and inflate tracheal tube cuffs to safe pressures. A model trachea was designed, incorporating a degree of compliance and an air leak, to evaluate six different pilot balloons grafted onto identical tracheal tubes. Pilot balloons were inflated to one of four pressures and anaesthetists were asked to estimate whether the pressure was acceptable, too low or too high. Anaesthetists were then asked to inflate the cuff of each tube. Overall, 103 (42.9%) of anaesthetists' assessments of tracheal tube cuff pressures were correct (33% correct would be expected by chance, p = 0.002). Pressures generated by anaesthetists inflating tracheal tube cuffs were very variable. Median (IQR [range]) pressures for each pilot balloon ranged from 29 (17,43 [9,56]) cmH2O to 74 (49,114 [4,140]) cmH2O (p < 0.001). The design of the pilot balloon significantly affects anaesthetists' ability to inflate tracheal tube cuffs to safe pressures. [source] Pressure volume curves of paediatric laryngeal mask airwaysANAESTHESIA, Issue 5 2009C. J. Wallace Summary Hyperinflation of the laryngeal mask airway cuff may exert high pressure on pharyngeal and laryngeal structures. In vitro data show that high intra cuff pressures may occur when inflated to only 30% of the manufacturer's recommended maximum inflation volume. We prospectively assessed the pressure volume curves of paediatric sized laryngeal mask airways (size 1,3) in 240 consecutive children (0,15 years). Following laryngeal mask airway insertion the cuff was inflated with 1-ml increments of air up to the maximum recommended by the manufacturer. After each ml cuff pressure was measured. At the end all cuff pressures were adjusted to 55 cmH2O. The maximum recommended volume resulted in high intracuff pressures in all laryngeal mask airway brands and sizes studied. Approximately half the maximum volume produced a cuff pressure , 60 cmH2O. This occurred in all brands and all sizes studied. We recommend that cuff manometers should be used to guide inflation in paediatric laryngeal mask airways. [source] Pressures within air-filled tracheal cuffs at altitude , an in vivo studyANAESTHESIA, Issue 3 2004J. Henning Summary Aeromedical transport of mechanically ventilated critically ill patients is now a frequent occurrence. However, the performance of the air filled tracheal tube cuff at altitude has not been studied in vivo. We measured the tracheal cuff pressures at ground level and at 3000 ft, in 10 intubated patients. With air providing the seal in the cuff the mean rise in cuff pressure was 23 cmH2O, which took the pressures above the critical perfusion pressure of the tracheal mucosa. This could lead to tracheal injury. [source] Blood Pressure Components in Clinical HypertensionJOURNAL OF CLINICAL HYPERTENSION, Issue 9 2006Michel E. Safar MD This review offers a critical evaluation of the remarkable progress in antihypertensive therapy since its inception. Despite the introduction of newer, more sophisticated drugs, treatment results have remained stable. Problems impeding further improvement include limited patient compliance, clinical inertia, incomplete adherence to guidelines, and dependence on brachial artery cuff pressures for diagnosis, risk assessment, and treatment response. Brachial artery systolic and pulse pressures do not reliably represent aortic or carotid artery pressures, which are better risk predictors for the heart and brain. Mean pressure, which is the same throughout the arterial tree, is directly measurable by cuff oscillometry, and might become the best single risk predictor. Available drugs have limited ability to decrease the aortic stiffness that is responsible for the elevated systolic blood pressure of aging. Therefore, to improve risk assessment and therapeutic benefit, we might include mean blood pressure and pulse pressure into blood pressure measurements, pursue efforts to measure central blood pressure, and search for new drugs to reduce arterial stiffness. [source] A new supraglottic airway device: LMA-SupremeÔ, comparison with LMA-ProsealÔACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2009T. HOSTEN Background and objective: The LMA-SupremeÔ (S-LMAÔ) is a new supraglottic airway device that presents combined features of flexibility, curved structure and single use and a different cuff structure. The purpose of this study was to compare the oropharyngeal leak pressures (OLP) of LMA-ProsealÔ (P-LMAÔ) and S-LMAÔ. Methods: Sixty adult patients were prospectively and randomly allocated to undergo insertion of P-LMAÔ (n=30) or S-LMAÔ (n=30). The cuffs were inflated until the intracuff pressure (ICP) reached 60 cm H2O. Orogastric leak pressures, insertion times, first attempt success rates, fiberoptical assessment of position, cuff pressures, orogastric tube (OGT) placement and OGT insertion times were compared. Unblinded observers collected intraoperative data and blinded observers collected post-operative data. Results: The first insertion attempts and time taken to provide an effective airway were similar between the groups. Two patients (P-LMAÔ, n=1; S-LMAÔ, n=1) were intubated due to excessive oropharyngeal leak and in one patient (P-LMAÔ, n=1) due to failed OGT placement. OLPs were similar (P-LMAÔ; 26.9±6.6 S-LMAÔ; 26.1±5.2). ICP increased significantly in the P-LMAÔ at the 30 and 60 min during anesthesia (P-LMAÔ; 80.1±12.8, 92.9±14.4, S-LMAÔ; 68.3±10.9, 73.7±15.6). OGT placement was successful in all patients in the S-LMAÔ, but failed in five patients in the P-LMAÔ (P=0.02). Fiberoptically determined anatomic position was better with the P-LMAÔ (P=0.03). Conclusion: Our findings suggest that S-LMAÔ had leak pressures similar to the P-LMAÔ, and this new airway device proved to be successful during both spontaneous and positive pressure ventilation. [source] The effect of pilot balloon design on estimation of safe tracheal tube cuff pressureANAESTHESIA, Issue 8 2010K. M. Janossy Summary We studied the effect of pilot balloon design on the ability of experienced anaesthetists to assess and inflate tracheal tube cuffs to safe pressures. A model trachea was designed, incorporating a degree of compliance and an air leak, to evaluate six different pilot balloons grafted onto identical tracheal tubes. Pilot balloons were inflated to one of four pressures and anaesthetists were asked to estimate whether the pressure was acceptable, too low or too high. Anaesthetists were then asked to inflate the cuff of each tube. Overall, 103 (42.9%) of anaesthetists' assessments of tracheal tube cuff pressures were correct (33% correct would be expected by chance, p = 0.002). Pressures generated by anaesthetists inflating tracheal tube cuffs were very variable. Median (IQR [range]) pressures for each pilot balloon ranged from 29 (17,43 [9,56]) cmH2O to 74 (49,114 [4,140]) cmH2O (p < 0.001). The design of the pilot balloon significantly affects anaesthetists' ability to inflate tracheal tube cuffs to safe pressures. [source] Pressure volume curves of paediatric laryngeal mask airwaysANAESTHESIA, Issue 5 2009C. J. Wallace Summary Hyperinflation of the laryngeal mask airway cuff may exert high pressure on pharyngeal and laryngeal structures. In vitro data show that high intra cuff pressures may occur when inflated to only 30% of the manufacturer's recommended maximum inflation volume. We prospectively assessed the pressure volume curves of paediatric sized laryngeal mask airways (size 1,3) in 240 consecutive children (0,15 years). Following laryngeal mask airway insertion the cuff was inflated with 1-ml increments of air up to the maximum recommended by the manufacturer. After each ml cuff pressure was measured. At the end all cuff pressures were adjusted to 55 cmH2O. The maximum recommended volume resulted in high intracuff pressures in all laryngeal mask airway brands and sizes studied. Approximately half the maximum volume produced a cuff pressure , 60 cmH2O. This occurred in all brands and all sizes studied. We recommend that cuff manometers should be used to guide inflation in paediatric laryngeal mask airways. [source] Pressures within air-filled tracheal cuffs at altitude , an in vivo studyANAESTHESIA, Issue 3 2004J. Henning Summary Aeromedical transport of mechanically ventilated critically ill patients is now a frequent occurrence. However, the performance of the air filled tracheal tube cuff at altitude has not been studied in vivo. We measured the tracheal cuff pressures at ground level and at 3000 ft, in 10 intubated patients. With air providing the seal in the cuff the mean rise in cuff pressure was 23 cmH2O, which took the pressures above the critical perfusion pressure of the tracheal mucosa. This could lead to tracheal injury. [source] | ||||||||||