ICEAGE (Incidence of Complications following Emergency Abdominal surgery: Get Exercising): study protocol of a pragmatic, multicentre, randomised controlled trial testing physiotherapy for the prevention of complications and improved physical recovery after emergency abdominal surgery.

Background: Postoperative complications and delayed physical recovery are significant problems following emergency abdominal surgery. Physiotherapy aims to aid recovery and prevent complications in the acute phase after surgery and is commonplace in most first-world hospitals. Despite ubiquitous service provision, no well-designed, adequately powered, parallel-group, randomised controlled trial has investigated the effect of physiotherapy on the incidence of respiratory complications, paralytic ileus, rate of physical recovery, ongoing need for formal sub-acute rehabilitation, hospital length of stay, health-related quality of life, and mortality following emergency abdominal surgery. We hypothesise that an enhanced physiotherapy care package of additional education, breathing exercises, and early rehabilitation prevents postoperative complications and improves physical recovery following emergency abdominal surgery compared to standard care alone. Methods: The Incidence of Complications following Emergency Abdominal surgery: Get Exercising (ICEAGE) trial is a pragmatic, investigator-initiated, multicentre, patient- and assessor-blinded, parallel-group, active-placebo controlled randomised trial, powered for superiority. ICEAGE will compare standard care physiotherapy to an enhanced physiotherapy care package in 288 participants admitted for emergency abdominal surgery at three Australian hospitals. Participants will be randomised using concealed allocation to receive either standard care physiotherapy (education, single session of coached breathing exercises, and daily early ambulation for 15 min) or an enhanced physiotherapy care package (education, twice daily coached breathing exercises for a minimum 2 days, and 30 min of daily supervised early rehabilitation for minimum five postoperative days). The primary outcome is a respiratory complication within the first 14 postoperative hospital days assessed daily with standardised diagnostic criteria. Secondary outcomes include referral for sub-acute rehabilitation services, discharge destination, paralytic ileus, hospital length of stay and costs, intensive care unit utilisation, 90-day patient-reported complications and health-related quality of life and physical capacity, and mortality at 30 days and at 1 year following surgery. Discussion: The morbidity, mortality, and fiscal burdens following emergency abdominal surgery are some of the worst within surgery. Physiotherapy may be an effective, low-cost, minimal harm intervention to improve outcomes and reduce hospital utilisation following this surgery type. ICEAGE will test the benefits of this commonly provided intervention within a methodologically robust, multicentre, double-blinded, active-placebo controlled randomised trial. Trial registration: ACTRN 12615000318583. Registered 8 April 2015.

Identification of induced and naturally occurring conductive hearing loss in mice using bone conduction.

While many mouse models of hearing loss have been described, a significant fraction of the genetic defects in these models affect both the inner ear and middle ears. A common method used to separate inner-ear (sensory-neural) from middle-ear (conductive) pathologies in the hearing clinic is the combination of air-conduction and bone-conduction audiometry. In this report, we investigate the use of air- and bone-conducted evoked auditory brainstem responses to perform a similar separation in mice. We describe a technique by which we stimulate the mouse ear both acoustically and via whole-head vibration. We investigate the sensitivity of this technique to conductive hearing loss by introducing middle-ear lesions in normal hearing mice. We also use the technique to investigate the presence of an age-related conductive hearing loss in a common mouse model of presbycusis, the BALB/c mouse.

Middle-ear and inner-ear contribution to bone conduction in chinchilla: The development of Carhart's notch.

While the cochlea is considered the primary site of the auditory response to bone conduction (BC) stimulation, the paths by which vibratory energy applied to the skull (or other structures) reaches the inner ear are a matter of continued investigation. We present acoustical measurements of sound in the inner ear that separate out the components of BC stimulation that excite the inner ear via ossicular motion (compression of the walls of the ear canal or ossicular inertia) from the components that act directly on the cochlea (cochlear compression or inertia, and extra-cochlear 'third-window' pathways). The results are consistent with our earlier suggestion that the inner-ear mechanisms play a large role in bone-conduction stimulation in the chinchilla at all frequencies. However, the data also suggest the pathways that conduct vibration to the inner ear via ossicular-motion make a significant contribution to the response to BC stimulation in the 1-3 kHz range, such that interruption of these path leads to a 5 dB reduction in total stimulation in that frequency range. The mid-frequency reduction produced by ossicular manipulations is similar to the 'Carhart's notch' phenomenon observed in otology and audiology clinics in cases of human ossicular disorders. We also present data consistent with much of the ossicular-conducted sound in chinchilla depending on occlusion of the ear canal.

Power reflectance as a screening tool for the diagnosis of superior semicircular canal dehiscence.

HYPOTHESIS: Power reflectance (PR) measurements in ears with superior canal dehiscence (SCD) have a characteristic pattern, the detection of which can assist in diagnosis. BACKGROUND: The aim of this study was to determine whether PR coupled with a novel detection algorithm can perform well as a fast, noninvasive, and easy screening test for SCD. The screening test aimed to determine whether patients with various vestibular and/or auditory symptom(s) should be further considered for more expensive and invasive tests that better define the diagnosis of SCD (and other third-window lesions). METHODS: Power reflectance was measured in patients diagnosed with SCD by high-resolution computed tomography. The study included 40 ears from 32 patients with varying symptoms (e.g., with and without conductive hearing loss, vestibular symptoms, and abnormal auditory sensations). RESULTS: Power reflectance results were compared to previously published norms and showed that SCD is commonly associated with a PR notch near 1 kHz. An analysis algorithm was designed to detect such notches and to quantify their incidence in affected and normal ears. Various notch detection thresholds yielded sensitivities of 80% to 93%, specificities of 69% to 72%, negative predictive values of 84% to 93%, and a positive predictive value of 67%. CONCLUSION: This study shows evidence that PR measurements together with the proposed notch-detecting algorithm can be used to quickly and effectively screen patients for third-window lesions such as SCD in the early stages of a diagnostic workup.

Evidence of inner ear contribution in bone conduction in chinchilla.

We investigated the contribution of the middle ear to the physiological response to bone conduction stimuli in chinchilla. We measured intracochlear sound pressure in response to air conduction (AC) and bone conduction (BC) stimuli before and after interruption of the ossicular chain at the incudo-stapedial joint. Interruption of the chain effectively decouples the external and middle ear from the inner ear and significantly reduces the contributions of the outer ear and middle ear to the bone conduction response. With AC stimulation, both the scala vestibuli Psv and scala tympani Pst sound pressures drop by 30-40 dB after the interruption. In BC stimulation, Psv decreases after interruption by about 10-20 dB, but Pst is little affected. This difference in the sensitivity of the BC induced Psv and Pst to ossicular interruption is not consistent with a BC response to ossicular motion, but instead suggests a significant contribution of an inner-ear drive (e.g., cochlear fluid inertia or compressibility) to the BC response. This article is part of a special issue entitled "MEMRO 2012".