OBJECTIVE

The Argus perineal sling is a minimally invasive surgical option to treat post-prostatectomy stress urinary incontinence (PPSUI). This study retrospectively evaluated the short-term clinical outcomes with the Argus sling for PPSUI management and determined the effects of potential preoperative parameters on intraoperative retrograde leak point pressure (RLPP).

METHODS

In this retrospective review of 16 men with various degrees of stress incontinence after prostatic surgery who underwent Argus sling, PPSUI was evaluated by pad usage, urodynamics, 24-hour pad weight, and validated questionnaires. Findings before and a minimum of 6 months after sling placement were compared. "Cure" was defined as no pad usage or the use of 1 pad for security; "improvement" was defined as a reduction in daily pad use by >50%.

RESULTS

After a mean (±SD) follow-up of 9.75 ± 3.51 months, 62.5% of patients were cured, 18.75% were improved, and 18.75% were still incontinent. Preoperative 24-hour pad weight was positively correlated with RLPP (P = .0121, r = 0.6286). Mean RLPP was 37.93 ± 3.45 cmH2 O. During follow-up, 44% of men had transient perineal or scrotal pain managed conservatively. Sling explantation, reported in 3 of 16 patients, was associated with urethral erosion or previous radiation therapy.

CONCLUSIONS

The Argus male sling can lead to satisfactory results in carefully selected patients. Increased stress urinary incontinence severity based on 24-hour pad weight required higher RLPP to achieve continence. Favorable satisfaction variables and quality of life scores are affected by appropriate intraoperative tensioning pressure.

OBJECTIVE

To compare the maximum pressure sustained by airways sealed with a resorbable ligation device (LigaTie) and with thoracoabdominal (TA) staples during thoracoscopic-assisted hilar lung lobectomies.

METHODS

In situ cadaveric study.

METHODS

Ten feline cadavers.

METHODS

Twenty lung lobectomies were performed with either a LigaTie or a TA stapler (n = 10 per group) by using a thoracoscopic-assisted technique. Procedures were randomly performed on the cranial lung lobes only. The distance between the ligation and the hilus was measured on each specimen. Airway pressures were tested to a maximum pressure of 40 cmH2 O.

RESULTS

All LigaTie sites reached a maximum airway pressure without leaking and were easily placed at the hilus. Four of 10 TA stapled sites leaked at a mean pressure of 22 cmH2 O (P = .010). All leaks occurred when the TA staple line was >5 mm from the hilus; no leaks occurred when the TA staple line was ≤5 mm from the hilus (P < .001). No difference was found between fresh and frozen cadavers (P = .483) or right vs left lung lobe (P = .284).

CONCLUSIONS

Lung lobectomies were consistently performed at the hilus only when the LigaTie was used. Lung lobectomies were less likely to leak when performed with the LigaTie rather compared with TA staples.

CONCLUSIONS

The LigaTie may be an effective alternative for lung lobectomies at the pulmonary hilus in cats and small breed dogs. Our findings provide justification for additional clinical testing.

BACKGROUND

It has been proposed that the analysis of positive end-expiratory pressure (PEEP)-induced volume changes can quantify alveolar recruitment. The potential of a lung to be recruited is expected to be high in acute respiratory distress syndrome (ARDS), where collapsed lung tissue is very common. The volume change that is beyond the delta volume because of the patient's compliance has been termed 'recruited volume' (RecV). However, data of patients with low and high RecV showed less severe lung disease in high 'recruiters', indicating that RecV may not equal the 'potentially recruitable lung tissue' seen in computed tomography scans. We hypothesized that RecV is higher in lung-healthy (LH) patients with little collapsed lung compared with ARDS patients.

METHODS

RecV and inspiratory capacity (IC) were determined in 12 LH and in 25 ARDS patients during incremental PEEP (steps of 2 cmH2 O). RecV was determined as the time-dependent increase in end-expiratory volume following the first expiration to the new PEEP level (ΔTDV). Gas distribution in LH patients was analyzed by electric impedance tomography.

RESULTS

Cumulative RecV(ΔTDV) and IC were higher (P < 0.01) in LH compared with ARDS patients, 1739 ml vs. 832 ml and 4432 ml vs. 2020 ml, respectively. In both groups, RecV correlated excellently with IC (R(2) = 0.86). In LH, RecV emanated mainly from nondependent lung regions at PEEP below 15 cmH2O. Maximum plateau pressure was reached with fewer PEEP steps in ARDS compared with LH patients (11 vs. 14, P < 0.01).

CONCLUSIONS

Our findings suggest that RecV predominately measures a slow fraction of inflation of already aerated lung tissue and not recruitment of collapsed alveoli.

OBJECTIVE

Even though numerous ventilators are licensed for a use in children, very few have been specifically developed for this age range. Therefore, home ventilators may not be able to adequately synchronize with the child's respiratory effort, and the inspiratory triggers (ITs) of assist modes are not always appropriate for children. The aim of the study was to test the improvement of the IT of a ventilator on a pediatric bench and in pediatric patients.

METHODS

A classical IT (ITc) and an improved IT [non-invasive ventilation (NIV) + IT] were tested on a bench with six pediatric profiles and in six young patients (mean age 14.1 ± 2.7 years old) requiring long-term NIV.

RESULTS

On the bench, trigger time delays (ΔT) and trigger pressures (ΔP) were reduced with the NIV + IT as compared with the ITc (ΔT: 0.481 ± 0.332 vs 0.079 ± 0.022 s for ITc and NIV + IT, respectively, P = 0.027; ΔP: -1.40 ± 0.70 vs -0.42 ± 0.28 cmH2 O for ITc and NIV + IT, respectively, P = 0.046). The clinical study confirmed the decrease in ΔT (0.267 ± 0.061 vs 0.178 ± 0.074 s for ITc and NIV + IT, respectively, P = 0.024) and ΔP (-0.68 ± 0.26 vs -0.39 ± 0.11 cmH2 O for ITc and NIV + IT, respectively, P = 0.030).

CONCLUSIONS

The sensitivity of the IT of a ventilator can be improved for pediatric use. The improvements observed on the bench study were confirmed in pediatric patients.

OBJECTIVE

The Brindley procedure, used since the 1980s, consists of implantation of a stimulator for sacral anterior root stimulation combined with a posterior sacral rhizotomy to enable micturition. Patients suitable for the procedure are patients with detrusor overactivity and a complete spinal cord lesion with intact sacral reflexes. S2 to S4 posterior sacral rhizotomy abolishes sacral hyperreflexia and may lead to decreased urethral closure pressure and loss of reflex adaptation of continence, leading to stress incontinence.

METHODS

In this retrospective study of 96 patients from Nantes or Le Mans, implanted with a Finetech-Brindley stimulator, we analyzed the incidence of stress incontinence one year after surgery and looked for predictive factors of stress incontinence one year after posterior sacral rhizotomy: age, gender, level of injury between T10 and L2 , previous urethral surgery, incompetent bladder neck, Maximum Urethral Closure Pressure before surgery less than 30 cmH2 O, compliance before surgery less than 30 ml/cmH2 0. Patients with persistent involuntary detrusor contractions with or without incontinence after surgery were excluded.

RESULTS

One year after surgery, 10.4% of the patients experienced stress incontinence. Urethral closure pressure was significantly decreased by 18% after posterior sacral rhizotomy (P = 0.002). This study highlights the only significant predictive factor of stress incontinence after rhizotomy: incompetent bladder neck (P = 0.002).

CONCLUSIONS

As screening of patients undergoing the Brindley procedure is essential to achieve optimal postoperative results, on the basis of this study, we propose preoperative assessment to select the population of patients most likely to benefit from the Brindley procedure.

A new dry spirometer (DS) incorporating a microcomputer for automatic calculation and direct read-out of spirometric parameters was compared to a calibrated Fleisch pneumotachograph (PT). Twenty-eight volunteers, including healthy subjects, obstructive and non-obstructive patients, performed a total of 48 spirometric tests with the two apparatuses randomly alternated. DS values for FVC were lower than those of the PT with a mean difference of 0.177 1 +/- 0.171 SD (p less than 0.0001). Mean FEV1 values were very similar in both apparatuses with a non significant difference of 0.003 1 +/- 0.182 FEF25-75 values were higher with the DS, showing a mean difference with the PT of 0.407 1 . s-1 +/- 0.324 (p less than 0.00001). The DS also gave slightly higher PEFR values than the PT, with a mean difference of 0.310 1 . s-1 +/- 0.830 (p less than 0.02). Differences in FVC readings between DS and PT were greater in severely obstructed patients (0.350 1 +/- 0.084, p less than 0.0001) than among healthy subjects (0.120 1 +/- 0.051, p less than 0.0002). On the contrary, in absolute figures DS values for FEF25-75 showed a greater difference with those of the PT in normals (0.547 1 . s-1 +/- 0.320, p less than 0.001) than in obstructed patients (0.288 1 . s-1 +/- 0.244, p less than 0.05). DS flow resistance was 2.67 cmH2). s. 1-1 for a flow of 8.8 1. s-1. Based on the spirometric differences observed, and on the high flow resistance and volume limitation imposed by its 6 1 capacity, we concluded that the apparatus tested cannot be recommended for clinical spirometry.

We investigated the flow rates of 25-G and 27-G spinal needles, of 90-mm and 120-mm lengths, from Vygon, BD, B. Braun and Pajunk; the needles had either a Luer connector, or a Surety® or UniVia® non-Luer connector. We used a bench-top model of entering the spinal space, pressurised to 35 cmH2 O to simulate cerebrospinal fluid pressure in the sitting position. We examined the time to first appearance of simulated cerebrospinal fluid in the needle hub, as well as the amount of fluid collected over 120 s after the needle was introduced. The mean (SD) times to first appearance of fluid in the needle hub of Luer spinal needles varied from 0.36 (0.22) s for the 25-G 90-mm BD to 3.14 (0.72) s for the 27-G 120-mm B. Braun, and in the non-Luer spinal needles from 0.22 (0.17) s for the 25-G 90-mm B. Braun to 2.99 (0.71) s for the 27-G 120-mm Pajunk. There was a significant difference in the time to first appearance of fluid in the needle hub between Luer and non-Luer needles of the same type for seven of 14 comparisons made, of which four showed slower appearance of fluid in the non-Luer version. In some of these cases, the time to appearance of fluid was nearly twice as long with the non-Luer counterpart. The mean (SD) weight of fluid collected in 120 s using the Luer spinal needles varied from 0.21 (0.05) g for the 27-G 120-mm Pajunk to 1.21 (0.18) g for the 25-G 90-mm Vygon, and using the non-Luer spinal needles from 0.25 (0.05) g for the 27-G 120-mm Pajunk to 1.55 (0.05) g for the 25-G 90-mm B. Braun. All of the needle types showed a greater weight of fluid collected using the non-Luer compared with the Luer version, with six of the 14 needle types showing a significant difference. Significant variations in flow were also seen between the same needle type from different manufacturers. We conclude that changing from Luer to non-Luer versions of spinal needles does not merely change the hub design and connection, but may introduce important differences in function.

OBJECTIVE

To assess whether crossing rectus abdominis muscle strips, as proposed by Yachia, would change urinary catheterizable conduit's pressure profilometry, in static and dynamic conditions.

METHODS

Non-randomized selection of 20 continent patients that underwent Macedo's ileum-based reservoir, 10 including Yachia's technique (Study Group) and 10 without this mechanism of continence (Control Group). Demographics and cystometric data were assessed. Conduit's pressure profilometry was obtained by infusing saline through a multichannel catheter, at rest and during Valsalva maneuver. We assessed the pressure: (a) in the bladder; (b) in conduit's proximal segment; and (c) in conduit's distal segment, which is presumably the abdominal wall and crossed muscle strips site.

RESULTS

Mean age at surgery was 6.1 years in the Control Group and 7.7 years in the Study Group. There was no statistically significant difference between groups regarding maximum cystometric bladder capacity and leakage point pressure. At rest, the pressure profilometry showed similar results between groups in all segments analyzed. During Valsalva maneuver, pressure profilometry showed similar results between groups in bladder and conduit's proximal segment pressure. In this condition, conduit's distal segment pressure in the Study Group (Mean = 72.9 and Peak = 128.7 cmH2 O) was significantly greater (P < 0.05) than conduit's distal segment pressure in the Control Group (Mean = 48.3 and Peak = 65.1 cmH2 O).

CONCLUSIONS

Crossing muscle strips over the conduit significantly increases the pressure in its distal segment during contraction of the rectus abdominis muscle, which can be important in moments of sudden increase in abdominal pressure in order to keep continence.

To evaluate the effects of age, height and prechallenge respiratory system resistance (Rrs) on bronchial responsiveness to methacholine inhalation (BRm) as measured by the oscillation technique in children with mild asthma, we studied BRm in 92 atopic children aged from 8 to 13 years (mean +/- SD, 10.5 +/- 1.7 years). Inhalation challenge was performed by administering progressively doubling doses of methacholine, until a twofold increase in Rrs from baseline had been reached. The minimum cumulative dose of methacholine (Dmin) at which Rrs deviated from baseline was identified by the point of deflection of the continuously recorded Rrs tracing. The Dmin represented the amount of methacholine which elicited BRm. By using single-regression analysis, height was negatively correlated with Rrs (p < 0.001). Height was positively and Rrs was negatively correlated with age (p < 0.001 and p < 0.001, respectively). Furthermore, height and age were correlated with Dmin (p < 0.001 and p < 0.001, respectively), but prechallenge Rrs was not correlated with Dmin (p>> 0.1). To minimize the effect of height and prechallenge Rrs on BRm, the relationships between Dmin and age was studied in a subgroup with a narrow range of heights (135-155 cm, n = 32), and a narrow range of prechallenge Rrs (5.0-6.9 cmH2 O/L/s, n = 42); there remained a statistically significant correlation between Dmin and age in the groups with comparable heights (p = 0.026) and Rrs (p = 0.003). These data suggest that the BHR in childhood asthma may be affected by height and age when measured by the oscillation technique. Considering the many advantages of the oscillation method, this technique may be very suitable for measuring BHR in childhood asthma.

The ability to gently ventilate a patient's lungs using a self-inflating bag requires a properly working adjustable pressure-limiting (APL) valve. We compared the performance of the APL valves of the GE Aisys CS2 and the Draeger Fabius anaesthetic machines during closure and opening from 1-20 and from 20-1 cmH2 O, using standardised experimental baby and adolescent patient lung models. Airway pressures and inspiratory tidal volumes were measured using an ASL-5000 test lung and a GE Aisys CS2 near-patient spirometry sensors. In both lung models, the GE Aisys CS2 APL valves demonstrated non-linear behaviours for airway pressures and for inspiratory tidal volumes, with a sharp increase at set APL pressure levels of 8-10 cmH2 O. With further closure of the GE Aisys CS2 APL valves up to 20 cmH2 O, inspiratory tidal volumes decreased to ~50% of the highest values measured. Airway pressures in the Draeger Fabius APL valves demonstrated a near linear increase and decrease. Airway pressure values measured in the Draeger Fabius were never higher than those set by the APL valves, whereas in the GE Aisys CS2 , they considerably exceeded set pressures (by up to 27 cmH2 O). We conclude that the performance of the GE Aisys CS2 APL valve does not allow safe bag-assisted ventilation of a patient's lungs.

There is debate whether pressure transmission within the lungs and alveolar collapse follow a hydrostatic pattern or the compression exerted by the weight of the heart and the diaphragm causes collapse localized in the areas adjacent to these structures. The second hypothesis proposes the existence of a cephalocaudal gradient in alveolar collapse. We aimed to define whether or not lung density and collapse follow a 'liquid-like' pattern with homogeneous isogravitational layers along the cephalocaudal axis in acute respiratory distress syndrome lungs.

Acute respiratory distress syndrome patients were submitted to full lung computed tomography scans at positive end-expiratory pressure (PEEP) zero (before) and 25 cmH2 O after a maximum-recruitment maneuver. PEEP was then decreased by 2 cmH2 O every 4 min, and a semi-complete scan performed at the end of each PEEP step.

Lung densities were homogeneous within each lung layer. Lung density increased along the ventrodorsal axis toward the dorsal region (β = 0.49, P < 0.001), while there was no increase, but rather a slight decrease, toward the diaphragm along the cephalocaudal axis and toward the heart. Higher PEEP attenuated density gradients. At PEEP 18 cmH2 O, dependent lung regions started to collapse massively, while best compliance was only reached at a lower PEEP.

We could not detect cephalocaudal gradients in lung densities or in alveolar collapse. Likely, external pressures applied on the lung by the chest wall, organs, and effusions are transmitted throughout the lung in a hydrostatic pattern with homogeneous consequences at each isogravitational layer. A single cross-sectional image of the lung could fully represent the heterogeneous mechanical properties of dependent and non-dependent lung regions.

To determine the effects of controlled release of insulin-like growth factor 1 (IGF-1) from alginate-poly-L-ornithine-gelatine (A-PLO-G) microbeads on external urethral sphincter (EUS) tissue regeneration in a rat model of stress urinary incontinence (SUI), as SUI diminishes the quality of life of millions, particularly women who have delivered vaginally, which can injure the urethral sphincter. Despite several well-established treatments for SUI, growth factor therapy might provide an alternative to promote urethral sphincter repair.

In all, 44 female Sprague-Dawley rats were randomised into four groups: vaginal distension (VD) followed by periurethral injection of IGF-1-A-PLO-G microbeads (VD + IGF-1 microbeads; 1 × 104 microbeads/1 mL normal saline); VD + empty microbeads; VD + saline; or sham-VD + saline (sham).

Urethral function (leak-point pressure, LPP) was significantly lesser 1 week after VD + saline [mean (sem) 23.9 (1.3) cmH2 O] or VD + empty microbeads [mean (sem) 21.7 (0.8) cmH2 O) compared to the sham group [mean (sem) 44.4 (3.4) cmH2 O; P < 0.05), indicating that the microbeads themselves do not create a bulking or obstructive effect in the urethra. The LPP was significantly higher 1 week after VD + IGF-1 microbeads [mean (sem) 28.4 (1.2) cmH2 O] compared to VD + empty microbeads (P < 0.05), and was not significantly different from the LPP in sham rats, demonstrating an initiation of a reparative effect even at 1 week after VD. Histological analysis showed well-organised skeletal muscle fibres and vascular development in the EUS at 1 week after VD + IGF-1 microbeads, compared to substantial muscle fibre attenuation and disorganisation, and less vascular formation at 1 week after VD + saline or VD + empty microbeads.

Periurethral administration of IGF-1-A-PLO-G microbeads facilitates recovery from SUI by promoting skeletal myogenesis and revascularisation. This therapy is promising, but detailed and longer term studies in animal models and humans are needed.

The critical care management of pleural air leaks can be challenging in all patients, but particularly in patients on mechanical ventilation. To investigate the effect of central airway pressure and pleural pressure on pulmonary air leaks, we studied orotracheally intubated mice with pleural injuries. We used clinically relevant variables - namely, airway pressure and pleural pressure - to investigate flow through peripheral air leaks. The model studied the pleural injuries using a pressure-decay maneuver. The pressure-decay maneuver involved a 3 sec ramp to 30 cmH2 0 followed by a 3 sec breath hold. After pleural injury, the pressure-decay maneuver demonstrated a distinctive airway pressure time history. Peak inflation was followed by a rapid decrease to a lower plateau phase. The decay phase of the inflation maneuver was influenced by the injury area. The rate of pressure decline with multiple injuries (28 ± 8 cmH2 0/sec) was significantly greater than a single injury (12 ± 3 cmH2 O/sec) (P < 0.05). In contrast, the plateau phase pressure was independent of injury surface area, but dependent upon transpulmonary pressure. The mean plateau transpulmonary pressure was 18 ± 0.7 cm H2 O. Finally, analysis of the inflation ramp demonstrated that nearly all volume loss occurred at the end of inflation (P < 0.001). We conclude that the air flow through peripheral lung injuries was greatest at increased lung volumes and limited by peripheral airway closure. In addition to suggesting an intrinsic mechanism for limiting flow through peripheral air leaks, these findings suggest the utility of positive end-expiratory pressure and negative pleural pressure to maintain lung volumes in patients with pleural injuries.

BACKGROUND

The objective of this work was to determine the failure pressures of 3 commonly performed repair techniques of 5-mm dural defects in a controlled setting.

METHODS

This was a pig dura ex vivo study. A testing apparatus was fabricated to study failure pressures of 3 different repairs in a porcine model. Five-millimeter (5-mm) dural defects were created and plugged with autologous mucosa/Tisseel (MT) (Baxter International Inc.), fat graft (FG), and bath plug (BP) techniques. Saline solution was infused at 30 mL/hour to apply unidirectional pressure to the repair until failure occurred. Five dural repairs were performed for each arm of the trial, for a total of 15 trials.

RESULTS

The mean failure pressure of the MT repair was 4.3 ± 1.9 cmH2 O, of the FG repair was 10.9 ± 4.2 cmH2 O, and of the BP repair was 20.7 ± 2.2 cmH2 O. Differences among mean failure pressures were statistically significant.

CONCLUSIONS

The BP repair showed significantly higher tolerances for pressure than the other 2 repairs. The BP repair was the only technique that withstood adult physiologic supine cerebrospinal fluid (CSF) pressure.

Continuous positive airway pressure (CPAP) by face mask is commonly performed in newborn resuscitation. We evaluated the effect of face mask CPAP on system dead space.

Face mask CPAP increases dead space.

A CPAP model study.

We estimated the volume of the inner space of the mask. We devised a face mask CPAP model, in which the outlet of the mask was covered with plastic; and three modified face mask CPAP models, in which holes were drilled near to the cushion of the covered face mask to alter the air exit. We passed a continuous flow of 21% oxygen through each model and we controlled the inner pressure to 5 cmH2 O by adjusting the flow-relief valve. To evaluate the ventilation in the inner space of each model, we measured the oxygen concentration rise time, that is, the time needed for the oxygen concentration of each model to reach 35% after the oxygen concentration of the continuous flow was raised from 21% to 40%.

The volume of inner space of the face mask was 38.3 ml. Oxygen concentration rise time in the face mask CPAP model was significantly longer at various continuous flow rates and points of the inner space of the face mask compared with that of the modified face mask CPAP model.

Our study indicates that face mask CPAP leads to an increase in dead space and a decrease in ventilation efficiency under certain circumstances. Pediatr Pulmonol. 2017;52:107-111. © 2016 Wiley Periodicals, Inc.

BACKGROUND

Guidelines recommend avoiding excessive oxygen during neonatal resuscitation. Recent studies have suggested that oxygen titration can be achieved using a self-inflating bag, but data on the effectiveness of resuscitators used in neonatal ventilation are scarce, The aim of this study was therefore to determine the amount of oxygen delivered using several brands of neonatal self-inflating resuscitation bags without reservoirs under different conditions with regard to oxygen flow rate, ventilation rate (VR), peak inspiratory pressure (PIP) range, and test lung compliance.

METHODS

Oxygen concentration was measured under a variety of conditions. Combinations of oxygen flow rate (10, 5.0, 3.0 and 1.0 L/min), VR (40, 60 inflations/min), PIP range (20-25 cmH2 O, 35-40 cmH2 O), and test lung compliance (0.6, 1.0, 3.0, and 5.0 mL/cmH2 O) were examined using six kinds of self-inflating bag.

RESULTS

Delivered oxygen concentration varied widely (30.1-96.7%) and had a significant positive correlation with gas flow rate in all of the bags. Delivered oxygen concentration was also negatively correlated with PIP in all of the bags and with VR in some of them. Test lung compliance did not affect delivered oxygen concentration.

CONCLUSIONS

The use of neonatal resuscitation self-inflating bags without reservoirs resulted in different delivered oxygen concentrations depending on gas flow rate, VR, PIP, and manufacturer, but not on lung compliance. This suggests that targeted oxygen concentrations could be delivered, even in lungs with decreased compliance, during resuscitation.

The trachea is essential to respiratory function and is a mechanically and biochemically complex composite tissue. Tissue-engineering approaches to treat tracheal diseases require detailed knowledge of the native mechanical and biochemical properties of the trachea. Although the porcine trachea represents an excellent preclinical model, relevant mechanical and biochemical composition are incompletely characterized.

Experimental. The mechanical and biochemical properties of 12 intact porcine tracheas were determined to characterize their compliance, as well as the aggregate modulus, bidirectional elastic modulus, hydraulic permeability, and biochemical characteristics of individual cartilage rings.

Data demonstrate the glycosaminoglycan content of tracheal rings was (mean ± standard deviation) 190 ± 49 μg/mg. Hydroxyproline content was 8.2 ± 3.2 μg/mg, and DNA content was 1.3 ± 0.27 μg/mg, a four-fold difference between circumferential elastic modulus (5.6 ± 2.0 megapascal [MPa]) and longitudinal composite elastic modulus (1.1 ± 0.7 MPa, P < 0.0001) was also observed. Aggregate modulus (stiffness) of porcine tracheal rings was 1.30 ± 0.28 MPa, and inflationary compliance was 0.00472 ± 0.00188 cmH2 O(-1) .

This study presents a comprehensive characterization of the relevant biochemical and mechanical properties of porcine tracheal cartilage, which is considered an excellent candidate for xenogenic tracheal graft and a source for tissue-engineered tracheal reconstruction. The range of parameters characterized in this study agrees with those reported for hyaline cartilage of the airway in other species. These characteristics can be used as quantitative benchmarks for tissue-engineering approaches to treat tracheal disease.

NA. Laryngoscope, 126:E325-E331, 2016.

OBJECTIVE

The aim of this study is to establish an optimized, minimally invasive transurethral catheterization cystometry (TUCC) and a novel urethral pressure profile (UPP) measurement for mice.

METHODS

The optimized TUCC and the UPP measurement were first established. This optimized TUCC was then performed in 16 anesthetized female mice and compared with the suprapubic catheterization cystometry (SCC) in parallel after suprapubic catheters implantation (SCI; on zero, third, and seventh day, respectively). Finally, the optimized TUCC and novel UPP measurement were applied to investigate in another eight mice of partial bladder outlet obstruction (pBOO) model. The urodynamic parameters including micturition pressure (MP), basal pressure (BP), threshold pressure (TP), bladder capacity (BC), micturition volume (MV), residual urine (RV), bladder compliance (COM), maximum urethral pressure (MUP), bladder pressure curve and UPP were recorded. Statistical cross-comparisons of parameters for two kinds of cystometries and pBOO model were performed.

RESULTS

Compared with the optimized TUCC before SCI, the MV, RV, BC, and MP decreased significantly on the seventh day after SCI (270.4-132.5 µL, 46.13-20.09 µL, 316.4-152.5 µL, 30.01-24.34 cmH2 0, respectively). After SCI, the BP, MP, TP, MV, RV, BC, and COM showed no significant difference between the TUCC and SCC at the same time point. The MUP increased significantly after pBOO operation (19.1-46.6 cmH2 0, P < 0.05).

CONCLUSIONS

The minimally invasive TUCC along with UPP measurement could be widely applied to study the bladder function of mice as a feasible, repeatable, and accessible method.

OBJECTIVE

Laryngeal mask airway (LMA) cuff pressure increases when the air is used for the cuff inflation during oxygen: nitrous oxide (O2:N2O) anaesthesia, which may lead to various problems. We compared the effects of different gases for ProSeal LMA™ (PLMA) cuff inflation in adult patients for various parameters.

METHODS

A total of 120 patients were randomly allocated to four groups, according to composition of gases used to inflate the PLMA cuff to achieve 40 cmH2 O cuff pressure, air (Group A), 50% O2 :air (Group OA), 50% O2:N2O (Group ON) and 100% O2 (Group O). Cuff pressure, cuff volume and ventilator parameters were monitored intraoperatively. Pharyngolaryngeal parameters were assessed at 1, 2 and 24 h postoperatively. Statistical analysis was performed using ANOVA, Fisher's exact test and step-wise logistic regression.

RESULTS

Cuff pressure significantly increased at 10, 15 and 30 min in Group A, OA and O from initial pressure. Cuff pressure decreased at 5 min in Group ON (36.6 ± 3.5 cmH2 O) (P = 0.42). PLMA cuff volume increased in Group A, OA, O, but decreased in Group ON (6.16 ± 2.8 ml [P < 0.001], 4.7 ± 3.8 ml [P < 0.001], 1.4 ± 3.19 ml [P = 0.023] and - 1.7 ± 4.9 ml [P = 0.064], respectively), from basal levels. Ventilatory parameters were comparable in all four groups. There was no significant association between sore throat and cuff pressure, with odds ratio 1.002.

CONCLUSIONS

Cuff inflation with 50% O2:N2O mixture provided more stable cuff pressure in comparison to air, O2 :air, 100% O2 during O2:N2O anaesthesia. Ventilatory parameters did not change with variation in PLMA cuff pressure. Post-operative sore throat had no correlation with cuff pressure.

BACKGROUND

Laryngeal clefts (LC) are uncommon but important causes of stridor in infants. Direct laryngoscopy is the recommended method for the detection of LC because LC may be missed by flexible endoscopy. As laryngomalacia by far outnumbers any other cause of stridor in this age group flexible bronchoscopy is usually the preferred method for the evaluation of significant infantile stridor. The aim is to illustrate how the application of CPAP assists the detection of LC during flexible endoscopy.

METHODS

Continuous positive airway pressure (CPAP) is applied via endoscopy mask during flexible endoscopy, titrated to open the upper esophageal sphincter, and to spread the inter-arytenoid folds.

RESULTS

The application of CPAP of 10-15 cmH2 O resulted in visual unmasking of otherwise obscured LC in four young children assessed for congenital stridor.

CONCLUSIONS

CPAP helps visualize LC by flexible endoscopy obviating transition to direct laryngoscopy and manual exploration.

OBJECTIVE

Functional and urodynamic (UDS) outcomes of W-configured ileal orthotopic neobladder (ONB) with extramural serosa-lined tunnel uretero-ileal anastomosis are presented

METHODS

Consecutive 17 patients undergoing ONB during December 2009 to March 2011 were enrolled. Of these 15 men (bladder cancer 14, tuberculosis 1) with mean age 52.7 ± 11.3 years completed the follow-up. Pouch-related quality of life (PQOL) was assessed using a published questionnaire. Uroflowmetry, cystometry/cystography and urethral-pressure profilometry were done at two follow-up visits at least 3 months apart. Mean follow up 10 ± 5 months. Mean length of harvested ileum 48 ± 6 cm.

RESULTS

Overall PQOL were similar at both evaluations (55 ± 11 and 54 ± 15, respectively). During first and second follow-up, maximum flow-rate, voided-volume and post-void residual urine were 11 ± 4 mL/sec, 246 ± 99 mL and 68 ± 74.9 mL and 10.4 ± 4.6 mL/sec, 234 ± 138 mL and 86 ± 146 mL, respectively. Mean neobladder capacity, compliance, maximum urethral closure-pressure (MUCP) and functional urethral length were 484 ± 244 mL, 50.5 ± 49.1 mL/cmH2 O, 42 ±20 cmH2 O and 22 ± 12 mm, and 468 ± 250 mL, 46.4 ± 47.5 mL/cmH2 O, 52 ± 27cmH2 O and 23 ± 12 mm, respectively. Patients with smaller pouch (r = 0.828; P = 0.0001), longer urethral length (r = -0.392; P = 0.023) and lesser incontinence (r = 0.429; P = 0.011) had significantly better PQOL. With continued supervised pelvic-floor rehabilitation, a trend in improvement in hesitancy (P = 0.058), MUCP (P = 0.05) and bothersome incontinence (P = NS) was observed. None of the patients had any obstruction or reflux of the upper tracts.

CONCLUSIONS

The index ONB has reasonable storage and voiding characteristics but with a rider of nocturnal urinary incontinence.

Background Preoxygenation is performed before induction of anaesthesia which increases oxygen reserve and provides delayed onset of hypoxia during period of apnea. Several techniques such as positive airway pressure and head-up tilt during preoxygenation have shown to prolong safe apnea period compared to conventional technique. However, uniform recommendations have not yet been made. Objective To find out the effect of combination of 5 cmH2 O continuous positive airway pressure (CPAP) and 25° head up position during preoxygenation on safe apnea period. Method In this comparative study 60 non-obese adult patients were divided into three equal groups; Group C receiving preoxygenation in conventional technique, Group S receiving preoxygenation with 5 cmH2 O continuous positive airway pressure in supine position and Group H receiving preoxygenation in 25° head-up position with 5 cmH2 O continuous positive airway pressure. After 3 min of preoxygenation, intubation was performed after induction of anaesthesia with propofol, fentanyl and succinylcholine. After confirming the tracheal intubation by direct visualization, all patients were administered vecuronium to maintain neuromuscular blockade. Postintubation, patients in all groups were left in same position with the tracheal tube exposed to atmosphere and without being ventilated till the SpO2 dropped to 92%. The primary outcome compared between the groups was the safe apnea period (time from loss of consciousness to fall of SpO2 to 92%). Result The duration of safe apnea period was longer (p < 0.05) in Group H patients (405.9 ± 106.69 s) as compared to the Group C (296.9 ± 99.01s) and Group S (319.65 ± 71.54s). Although the duration of safe apnea period was longer in the Group S as compared to Group C the difference was not statistically significant. Conclusion Preoxygenation in 25° head-up position with 5 cm H2O continuous positive airway pressure significantly prolongs safe apnea period in non-obese adults compared to supine position, with or without 5 cmH2O continuous positive airway pressure.

OBJECTIVE

To describe a suture-free ureterovesical anastomosis using a microvascular anastomotic system (MAS) and compare the surgical time and bursting pressure to a sutured ureterovesical anastomosis (SA) with and without an extravesical seromuscular tunnel (EVSMT).

METHODS

Randomized, unblocked design, ex vivo study.

METHODS

Three canine cadavers.

METHODS

For each cadaver, the ureters were sectioned into 3 equal lengths. The 6 sections were randomly assigned to receive either the MAS or end-side SA. The first cadaver (3 MAS, 3 SA) was used to refine the technique, and the remaining 2 cadavers were used for evaluation. Surgical time and bursting pressure of the anastomosis were compared between MAS and SA (n = 6 per technique). After bursting pressure testing of each anastomosis, an SMT was created over the anastomoses. Bursting pressures were again recorded and compared across techniques.

RESULTS

The surgery time was significantly shorter for MAS (median 5.4 minutes) than SA (median 15.8 minutes; P = .002). The bursting pressure was significantly higher for MAS (median 189.5 cmH2 O) than SA (median 64 cmH2 O; P = .002). The bursting pressure for MAS-EVSMT (median 398.5 cmH2 O) was not significantly different from the SA-EVSMT (median 321 cmH2 O, P = .567); however, the creation of an SMT significantly increased the bursting pressure for both techniques (P = .028, respectively).

CONCLUSIONS

This study demonstrated the feasibility of a suture-free ureterovesical anastomosis in the canine cadaver using a commercially available MAS. The MAS anastomosis was faster and resulted in higher bursting pressures than SA. The creation of an SMT improved the bursting resistance of both techniques but there was no difference between the techniques covered by an EVSMT.

OBJECTIVE

Peritron+ is a new handheld device, which can be attached to a urethral catheter to measure intravesical pressures (Pves). The goal of this study was to assess if Pves recorded by standard urodynamics (UDs) are comparable to those recorded by the Peritron+.

METHODS

Patients with voiding dysfunction and an indication for UD underwent measurement of Pves with nonvideo UD and Peritron+. Pves were recorded at volumes of 50, 100, and 200 mL for the supine and sitting positions. A failure of the Peritron+ was considered to be a discrepancy of Pves values >3 cmH2 O between Peritron+ and UD recordings. Two-way ANOVA was used to assess for statistical significance. P-values < 0.05 were considered significant.

RESULTS

Ten female patients, mean age 51 years old, were enrolled in the study. The difference in Pves measurements between Peritron+ and UD were ≤3 cmH2 O at all bladder volumes measured in a supine and sitting positions. There were no adverse events and there were no malfunctions of the Peritron+ device during the study.

CONCLUSIONS

Peritron+ handheld device accurately assessed Pves at different intravesical volumes when compared to UD measurements. The Peritron+ is a simple and safe device, which can be used in the office by a clinician and at home by a patient to monitor Pves and help to select patients who may require standard UD re-evaluation. This will be a valuable tool in managing patients with neurogenic and nonneurogenic bladders who are at a risk of upper urinary tract deterioration.