Eye-tracking during simulation-based echocardiography: a feasibility study.

INTRODUCTION: Due to the technical progress point-of-care ultrasound (POCUS) is increasingly used in critical care medicine. However, optimal training strategies and support for novices have not been thoroughly researched so far. Eye-tracking, which offers insights into the gaze behavior of experts may be a useful tool for better understanding. The aim of this study was to investigate the technical feasibility and usability of eye-tracking during echocardiography as well as to analyze differences of gaze patterns between experts and non-experts. METHODS: Nine experts in echocardiography and six non-experts were equipped with eye-tracking glasses (Tobii, Stockholm, Sweden), while performing six medical cases on a simulator. For each view case specific areas of interests (AOI) were defined by the first three experts depending on the underlying pathology. Technical feasibility, participants' subjective experience on the usability of the eye-tracking glasses as well as the differences of relative dwell time (focus) inside the areas of interest (AOI) between six experts and six non-experts were evaluated. RESULTS: Technical feasibility of eye-tracking during echocardiography was achieved with an accordance of 96% between the visual area orally described by participants and the area marked by the glasses. Experts had longer relative dwell time in the case specific AOI (50.6% versus 38.4%, p = 0.072) and performed ultrasound examinations faster (138 s versus 227 s, p = 0.068). Furthermore, experts fixated earlier in the AOI (5 s versus 10 s, p = 0.033). CONCLUSION: This feasibility study demonstrates that eye-tracking can be used to analyze experts and non-experts gaze patterns during POCUS. Although, in this study the experts had a longer fixation time in the defined AOIs compared to non-experts, further studies are needed to investigate if eye-tracking could improve teaching of POCUS.

The effect of oral Δ-9-tetrahydrocannabinol on the minimal alveolar concentration of sevoflurane: A randomised, controlled, observer-blinded experimental study.

BACKGROUND: Cannabis has increasingly been used for medical and recreational purposes. The main pharmacological compound in cannabis is tetrahydrocannabinol (THC), which has sedative, anxiolytic and analgesic effects. In some animal models, THC has also been shown to reduce the minimum alveolar concentration (MAC) of halothane and cyclopropane, but its effect on sevoflurane, currently the most commonly used inhalational anaesthetic agent, has not been investigated. OBJECTIVE: To investigate the effect of THC on the MAC of sevoflurane in rats. METHODS: Observer-blinded, randomised controlled trial. SETTING: Centre for Biomedical Research of the Medical University of Vienna, 2019. INDIVIDUALS: Thirty-eight adult Wistar rats. INTERVENTIONS: The rats were allocated randomly into one of two groups. Group A received THC 10 mg kg and group B received the corresponding volume of placebo via gastric gavage (administration through a tube placed in the distal oesophagus). The rats were then individually anaesthetised in an airtight sevoflurane-flooded chamber, and the MAC in both groups was determined using Dixon's up-and-down method. Blood samples were drawn to measure serum concentrations of THC. MAIN OUTCOME MEASURES: The primary outcome was the MAC of sevoflurane in Groups A and B. RESULTS: The bootstrap estimate of the MAC of sevoflurane was 2.1 (95% confidence interval 1.8 to 2.4) vol% in the THC group and 2.8 (95% confidence interval 2.7 to 2.9) vol% in the placebo group, corresponding to a significant MAC reduction of 26% in response to THC. CONCLUSION: Gastric administration of THC 10 mg kg significantly reduced the MAC of sevoflurane by 26%. TRIAL REGISTRATION: Not applicable.

Effects of extracorporeal membrane oxygenation pump flow, backflow cannulae, mean arterial blood pressure, and pulse pressure on Doppler-derived flow velocities of the lower limbs in patients on peripheral veno-arterial extracorporeal membrane oxygenation: A pilot study.

BACKGROUND: Reported rates of limb ischaemia on peripheral veno-arterial extracorporeal membrane oxygenation (pVA ECMO) vary from 1-52%. OBJECTIVES: Primary: To explore (i) the feasibility for appropriately trained intensive care unit staff to measure Doppler derived flow velocities of the lower limbs for patients on pVA ECMO; and (ii) whether these measurements are clinically useful. Secondary: explore the relationship between ECMO pump flow, backflow cannulae (BFC) properties, mean arterial blood pressure (MAP), and pulse pressure on flow velocities. METHOD: Inclusion criteria: age>18 years, on pVA ECMO >24 hours. EXCLUSION CRITERIA: any guardianship limitations and patients without a BFC. Serial patients receiving pVA-ECMO over a 10 month period had Doppler derived flow velocities of the lower limbs sampled. Simultaneously, other pertinent parameters were recorded. 80% inclusion was considered clinically feasible. Study personnel were asked for feedback regarding the ease and usefulness of studies. RESULTS: 15 of 17 patients were included: 88% inclusion. Mean peak systolic velocity (PSV) in the cannulated limb was 31 ± 29 cm/s in the dorsalis pedis (DP) and 27 ± 18 cm/s posterior tibial (PT). Similar flows were recorded in the non-cannulated limbs (DP 34 ± 29 cm/s, PT 44 ± 36 cm/s; P > 0.05). PSV was positively correlated with pulse pressure in cannulated and non-cannulated limbs respectively (r=0.63, P < 0.05; r=0.67 and P < 0.05). There was no significant correlation between PSV and MAP. ECMO pump flow and BFC were negatively correlated with PSV (r=-0.51, P < 0.05; r=-0.43, P < 0.05). CONCLUSION: It is generally feasible for ICU staff to measure flow velocities of the lower limbs for patients on pVA ECMO. It remains unclear how clinically useful these measurements are. Doppler derived flow velocities of arteries of the lower limbs of patients on pVA ECMO appear different to non-ECMO patients. PSV in the lower limbs of patients on pVA ECMO seems to be more related to pulse pressure than to other haemodynamic parameters.

Patients Undergoing Orthotopic Liver Transplantation Require Lower Concentrations of the Volatile Anesthetic Sevoflurane.

BACKGROUND: Sevoflurane is a volatile anesthetic commonly used to maintain anesthesia in patients with end-stage liver disease (ESLD) undergoing orthotopic liver transplantation (OLT). Growing evidence suggests that patients with ESLD have decreased anesthetic requirements compared to patients with preserved liver function. The potency of volatile anesthetics is expressed as the minimum alveolar concentration (MAC). In this prospective, blinded study, we compared the MAC of sevoflurane among patients with ESLD undergoing OLT and patients with normal liver function undergoing major abdominal surgery. METHODS: After propofol-induced anesthesia, the MAC of sevoflurane was assessed by evaluating motor response to initial skin incision in patients undergoing OLT and in patients with normal liver function undergoing major abdominal surgery. The MAC was determined using Dixon "up-and-down" method and compared between groups. In addition, the bispectral index was documented immediately before and after skin incision. RESULTS: Twenty patients undergoing OLT and 20 control patients were included in the study. The MAC of sevoflurane in patients undergoing OLT was 1.3% (95% confidence interval [CI], 1.1-1.4). In comparison, the MAC of sevoflurane in patients with normal liver function was 1.7% (95% CI, 1.6-1.9), equal to a relative reduction of the MAC in patients with ESLD of 26% (95% CI, 14-39). The bispectral index was higher in patients with ESLD than in control patients at 3 minutes before (47 [95% CI, 40-53] vs 35 [95% CI, 31-40], P = .011), 1 minute before (48 [95% CI, 42-54] vs 37 [95% CI, 33-43], P = .03), and 1 minute after skin incision (57 [95% CI, 50-64] vs 41 [95% CI, 36-47], P < .001). CONCLUSIONS: Our results suggest that the MAC of sevoflurane is lower in patients with ESLD than in patients with normal liver function after propofol-induced anesthesia. However, as we did not measure propofol concentrations at the time of skin incision, the difference in MAC should be interpreted with caution given that residual propofol may have been present at the time of skin incision.

Outcomes and potential for improvement in the prehospital treatment of penetrating chest injuries in a European metropolitan area: A retrospective analysis of 2009 - 2017.

BACKGROUND: Trauma is the leading cause of death in patients <45 years living in high-resource settings. However, penetrating chest injuries are still relatively rare in Europe - with an upwards trend. These cases are of particular interest to emergency medical services (EMS) due to available invasive treatment options like chest tube placement or resuscitative thoracotomy. To date, there is no sufficient data from Austria regarding penetrating chest trauma in a metropolitan area, and no reliable source to base decisions regarding further skill proficiency training on. METHODS: For this retrospective observational study, we screened all trauma emergency responses of the Viennese EMS between 01/2009 and 12/2017 and included all those with a National Advisory Committee for Aeronautics (NACA) score ≥ IV (= potentially life-threatening). Data were derived from EMS mission documentations and hospital files, and for those cases with the injuries leading to cardiopulmonary resuscitation (CPR), we assessed the EMS cardiac arrest registry and consulted a forensic physician. RESULTS: We included 480 cases of penetrating chest injuries of NACA IV-VII (83% male, 64% > 30 years old, 74% stab wounds, 16% cuts, 8% gunshot wounds, 56% inflicted by another party, 26% self-inflicted, 18% unknown). In the study period, the incidence rose from 1.4/100,000 to 3.5/100,000 capita, and overall, about one case was treated per week. In the cases with especially severe injury patterns (= NACA V-VII, 43% of total), (tension-)pneumothorax was the most common injury (29%). The highest mortality was seen in injuries to pulmonary vessels (100%) or the heart (94%). Fifty-eight patients (12% of total) deceased, whereas in 15 cases, the forensic physician stated survival could theoretically have been possible. However, only five of these CPR patients received at least unilateral thoracostomy. Regarding all penetrating chest injuries, thoracostomy had only been performed in eight patients. CONCLUSIONS: Severe cases of penetrating chest trauma are rare in Vienna and happened about once a week between 2009 and 2017. Both incidence and case load increased over the years, and potentially life-saving invasive procedures were only reluctantly applied. Therefore, a structured educational and skill retention approach aimed at both paramedics and emergency physicians should be implemented. TRIAL REGISTRATION: Retrospective analysis without intervention.

Landiolol for refractory ventricular fibrillation in out-of-hospital cardiac arrest: A randomized, double-blind, placebo-controlled, pilot trial.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) complicated by refractory ventricular fibrillation (VF) is associated with poor outcome. Beta-1-receptor selective blockade might overcome refractory VF and improve survival. This trial investigates the efficacy and safety of prehospital landiolol in OHCA and refractory VF. METHODS: In this randomized, double-blind, placebo-controlled pilot trial, patients with OHCA and recurrent or refractory VF (at least 3 defibrillation attempts and last rhythm shockable), pretreated with epinephrine and amiodarone, were allocated to receive add-on treatment with landiolol or placebo. Landiolol was given as a 20 mg bolus infusion. The primary efficacy outcome was time from trial drug infusion to sustained return of spontaneous circulation (ROSC). Safety outcomes included the onset of bradycardia and asystole. RESULTS: A total of 36 patients were enrolled, 19 were allocated to the landiolol group and 17 to the placebo group. Time from trial drug infusion to sustained ROSC was similar between treatment groups (39 min [landiolol] versus 41 min [placebo]). Sustained ROSC was numerically lower in the landiolol group compared with the placebo group (7 patients [36.8%] versus 11 patients [64.7%], respectively). Asystole within 15 min of trial drug infusion occurred significantly more often in the landiolol group than in the placebo group (7 patients [36.8%] and 0 patients [0.0%], respectively). CONCLUSION: In patients with OHCA and refractory VF who are pretreated with epinephrine and amiodarone, add-on bolus infusion of landiolol 20 mg did not lead to a shorter time to sustained ROSC compared with placebo. Landiolol might be associated with bradycardia and asystole.

The effect of a bolus dose of intravenous lidocaine on the minimum alveolar concentration of sevoflurane: a prospective, randomized, double-blinded, placebo-controlled trial.

BACKGROUND: The anesthetic effect of volatile anesthetics can be quantified by the minimum alveolar concentration (MAC) of the drug that prevents movement in response to a noxious stimulus in 50% of patients. The underlying mechanism regarding how immobilization is achieved by volatile anesthetics is not thoroughly understood, but several drugs affect MAC. In this study, we investigated the effect of a single IV bolus dose of lidocaine on the MAC of sevoflurane in humans. METHODS: We determined the MAC for sevoflurane using the Dixon "up-and-down" method in 3 groups of patients, aged 30 to 65 years, who underwent elective surgery (30 patients per group). Study medication (placebo, 0.75 mg·kg(-1) lidocaine or 1.5 mg·kg(-1) lidocaine) was administered 3 minutes before skin incision after a 15-minute equilibration period and the response to skin incision was recorded (movement versus no movement). RESULTS: MAC was 1.86% ± 0.40% in the placebo and 1.87% ± 0.45% in the 0.75 mg·kg(-1) lidocaine group (P = 1.00). MAC was 1.63% ± 0.24% in the 1.5 mg·kg(-1) lidocaine group, which was significantly lower than that of the placebo group (mean difference of 0.23% sevoflurane [95% adjusted confidence interval {CI}, 0.03-0.43]; P = 0.022). No significant difference was observed between the 0.75 mg·kg(-1) lidocaine and the placebo groups (mean difference of -0.01% sevoflurane [95% adjusted CI, -0.27 to 0.25]; P = 1). CONCLUSIONS: IV 1.5 mg·kg(-1) lidocaine decreased the MAC by at least 0.03% sevoflurane (mean difference 0.23% sevoflurane [95% adjusted CI, 0.03-0.43]). We did not observe a significant reduction in the MAC of sevoflurane with the IV administration of 0.75 mg·kg(-1) lidocaine.

The Performance of Opioid-Free Anesthesia for Bariatric Surgery in Clinical Practice.

PURPOSE: Opioid-free anesthesia (OFA) is an alternative to conventional opioid-based anesthesia (OBA) in patients undergoing bariatric surgery. Several small studies and a meta-analysis have suggested advantages of OFA for bariatric surgery, but current evidence is still contradictory, and a universally accepted concept has not yet been established. The purpose of this study was to determine whether patients undergoing bariatric surgery experience less postoperative pain and better postoperative recovery when anesthetized with an OFA regimen than with an OBA regimen. MATERIALS AND METHODS: This prospective observational cohort study, conducted between October 2020 and July 2021, compared patients receiving OFA with patients receiving OBA. Patients were visited 24 and 48 h after the surgical procedure and asked about their postoperative pain using the visual analogue scale (VAS). Additionally, the quality of recovery-40 questionnaire (QoR-40) and the postoperative opioid requirements were recorded. RESULTS: Ninety-nine patients were included and analyzed in this study (OFA: N = 50; OBA: N = 49). The OFA cohort exhibited less postoperative pain than the OBA cohort within 24 h (VAS median [interquartile range (IQR)]: 2.2 [1-4.4] vs. 4.1 [2-6.5]; P ≤ 0.001) and 48 h (VAS median [IQR]: 1.9 [0.4-4.1] vs. 3.1 [1.4-5.8]; P ≤ 0.001) postoperatively. Additionally, the OFA cohort had higher QoR-40 scores and required less opioid therapy postoperatively. CONCLUSION: Based on our results the use of OFA for bariatric surgery results in less pain, reduced opioid requirements, and improved postoperative recovery-adding additional evidence regarding the use of OFA in everyday clinical practice.

Feasibility of resuscitative transesophageal echocardiography at out-of-hospital emergency scenes of cardiac arrest.

Guidelines recommend the use of ultrasound in cardiac arrest. Transthoracic echocardiography, has issues with image quality and by increasing hands-off times during resuscitation. We assessed the feasibility of transesophageal echocardiography (TEE), which does not have both problems, at out-of-hospital cardiac arrest (OHCA) emergency scenes. Included were 10 adults with non-traumatic OHCA in Vienna, Austria. An expert in emergency ultrasound was dispatched to the scenes in addition to the resuscitation team. Feasibility was defined as the ability to collect specific items of information by TEE within 10 min. Descriptive statistics were compiled and hands-off times were compared to a historical control group. TEE examinations were feasible in 9 of 10 cases and prompted changes in clinical management in 2 cases (cardiac tamponade: n = 1; right ventricular dilatation: n = 1). Their mean time requirement was 5.1 ± 1.7 (2.8-8.0) min, and image quality was invariably rated as excellent or good during both compressions and pauses. No TEE-related complications, or interferences with activities of advanced life support were observed. The hands-off times during resuscitation were comparable to a historical control group not involving ultrasound (P = 0.24). Given these feasibility results, we expect that TEE can be used routinely at OHCA emergency scenes.

The Epidemiology of Pre-Hospital EMS Treatment of Geriatric Patients in the City of Vienna-An Overview.

Background: The city of Vienna, Austria, has a gradually aging population. Elderly people, over 65 years old and living at home or in nursing homes, frequently use Emergency Medical Services (EMS). However, there is no previous data comparing the EMS utilization of elderly- and non-elderly patients in Vienna. Methods: We retrospectively analyzed all EMS incidents in Vienna from 2012 to 2019. Transport- and emergency physician treatment rates, annual fluctuations, and the number of non-transports were compared between elderly (≥65 years) and non-elderly (18−64 years) patients. Results: Elderly people accounted for 42.6% of the total EMS responses in adult patients, representing an annual response rate of 223 per 1000 inhabitants ≥ 65 years. Compared to 76 per 1000 inhabitants in patients 18−64 years old, this results in an incidence rate ratio (IRR) of 2.93 [2.92−2.94]. Elderly people were more likely (OR 1.68 [1.65−1.70]) to need emergency physicians, compared to 18−64 year-olds. Nursing home residents were twice (OR 2.11 [2.06−2.17]) as likely to need emergency physicians than the rest of the study group. Non-transports were more likely to occur in patients over 65 years than in non-elderlies (14% vs. 12%, p < 0.001). Conclusions: The elderly population ≥ 65 years in Vienna shows higher EMS response rates than younger adults. They need emergency physicians more often, especially when residing in nursing homes. The economical and organizational strain this puts on the emergency response system should trigger further research and the development of solutions, such as specific response units dedicated to elderly people.

ST-T segment changes in prehospital emergency physicians in the field: a prospective observational trial.

AIMS: Due to time-critical decision-making, physical strain and the uncontrolled environment, prehospital emergency management is frequently associated with high levels of stress in medical personnel. Stress has been known to cause ischemia like changes in electrocardiograms (ECGs), including arrhythmias and deviations in ST-T segments. There is a lack of knowledge regarding the occurrence of changes in ST-T segments in prehospital emergency physicians. We hypothesized that ST-T segment deviations occur in prehospital emergency physicians in the field. METHODS: In this prospective observational trial, ST-T segments of emergency physicians were recorded using 12-lead Holter ECGs. The primary outcome parameter was defined as the incidence of ST-T segment changes greater than 0.1 mV in two corresponding leads for more than 30 s per 100 rescue missions. The secondary outcomes included T-wave inversions and ST-segment changes shorter than 30 s or smaller than 0.1 mV. Surrogate parameters of stress were measured using the NASA-Task Load Index and cognitive appraisal, and their correlation with ST-T segment changes were also assessed. RESULTS: Data from 20 physicians in 36 shifts (18 days, 18 nights) including 208 missions were analysed. Seventy percent of previously healthy emergency physicians had at least one ECG abnormality; the mean duration of these changes was 30 s. Significantly more missions with ECG changes were found during night than day shifts (39 vs. 17%, p < 0.001). Forty-nine ECG changes occurred between missions. No ST-T segment changes > 30 s and > 0.1 mV were found. Two ST-T segment changes < 30 s or < 0.1 mV (each during missions) and 122 episodes of T-wave inversions (74 during missions) were identified. ECG changes were found to be associated with alarms when asleep and NASA task load index. CONCLUSION: ECG changes are frequent and occur in most healthy prehospital emergency physicians. Even when occurring for less than 30 s, such changes are important signs for high levels of stress. The long-term impact of these changes needs further investigation. Trial registration The trial was registered at ClinicalTrials.gov (NCT04003883) on 1.7.2019:  https://clinicaltrials.gov/ct2/show/NCT04003883?term=emergency+physician&rank=2.

The Effect of Pregabalin on the Minimum Alveolar Concentration of Sevoflurane: A Randomized, Placebo-Controlled, Double-Blind Clinical Trial.

Background: Pregabalin is commonly used perioperatively to reduce post-operative pain and opioid consumption and to prevent the development of chronic pain. It has been shown to reduce anesthetic consumption in balanced anesthesia, but studies investigating its effect on the minimum alveolar concentration (MAC) of volatile anesthetics are lacking. The aim of this study was to investigate the effect of two different doses of pregabalin on the MAC of sevoflurane. Methods: In a randomized, double-blinded, placebo controlled clinical study, 75 patients were assigned to receive placebo, 300 mg pregabalin, or 150 mg pregabalin, as a capsule 1 h before anesthesia induction with sevoflurane only. After equilibration, the response to skin incision (movement vs. non-movement) was monitored. The MAC was assessed using an up- and down-titration method. Results: The MAC of sevoflurane was estimated as 2.16% (95% CI, 2.07-2.32%) in the placebo group, 1.44% (95% CI, 1.26-1.70%) in the 300 mg pregabalin group, and 1.81% (95% CI, 1.49-2.13%) in the 150 mg pregabalin group. We therefore report a 33% reduction in the MAC of sevoflurane in the 300 mg pregabalin group as compared to placebo. The MAC of the 150 mg pregabalin group was reduced by 16% as compared to placebo but was not statistically significant. Conclusions: The administration of 300 mg pregabalin reduced the MAC of sevoflurane by 33%, while the administration of 150 mg pregabalin did not significantly reduce the MAC of sevoflurane. Pregabalin use led to a small reduction in post-operative pain levels but increased side effects in a dose-dependent manner.

Ethanol reduces the minimum alveolar concentration of sevoflurane in rats.

A high number of trauma patients are under the influence of alcohol. Since many of them need immediate surgical procedures, it is imperative to be aware of the interaction of alcohol with general anesthesia. To counter challenges that arise from clinical studies, we designed an animal experiment in which 48 adult Wistar rats either received 1 g · kg-1 ethanol, 2 g · kg-1 ethanol or placebo via intraperitoneal application. Subsequently, they were anesthetized with an individual concentration of sevoflurane. The minimum alveolar concentration (MAC) of the different groups was assessed using Dixon's up-and-down design and isotonic regression methods. The bootstrap estimate of the MAC of sevoflurane in the placebo group was 2.24 vol% (95% CI 1.97-2.94 vol%). In the low dose ethanol group, the bootstrap estimate was 1.65 vol% (95% CI 1.40-1.98 vol%), and in the high dose ethanol group, it was 1.08 vol% (95% CI 0.73-1.42 vol%). We therefore report that intraperitoneal application of 1 g · kg-1 or 2 g · kg-1 ethanol both resulted in a significant reduction of the MAC of sevoflurane in adult Wistar rats: by 26.3% and 51.8% respectively as compared to placebo.

Remote real-time supervision of prehospital point-of-care ultrasound: a feasibility study.

BACKGROUND: Although prehospital point-of-care ultrasound (POCUS) is gaining in importance, its rapid interpretation remains challenging in prehospital emergency situations. The technical development of remote real-time supervision potentially offers the possibility to support emergency medicine providers during prehospital emergency ultrasound. The aim of this study was to assess the feasibility of live data transmission and supervision of prehospital POCUS in an urban environment and so to improve patients' safety. METHODS: Emergency doctors with moderate ultrasound experience performed prehospital POCUS in emergency cases (n = 24) such as trauma, acute dyspnea or cardiac shock using the portable ultrasound device Lumify™. The ultrasound examination was remotely transmitted to an emergency ultrasound expert in the clinic for real-time supervision via a secure video and audio connection. Technical feasibility as well as quality of communication and live stream were analysed. RESULTS: Prehospital POCUS with remote real-time supervision was successfully performed in 17 patients (71%). In 3 cases, the expert was not available on time and in 1 case remote data transmission was not possible due to connection problems. In 3 cases tele-supervision was restricted to video only and no verbal communication was possible via the device itself due to power saving mode of the tablet. CONCLUSION: Remote real-time supervision of prehospital POCUS in an urban environment is feasible most of the time with excellent image and communication quality. TRIAL REGISTRATION: ClinicalTrials Number NCT04612816.

Accurately Assessing Gay Men's Erectile Functioning: A Critique of the International Index of Erectile Function (IIEF) Use with Gay Men.

The International Index of Erectile Functioning (IIEF) has been widely used to measure gay men's erectile functioning. However, the IIEF was initially developed using a sample of men whose sexual orientation was unspecified. Using scales not validated for specific populations can result in inaccurate assessments. The purpose of the current study was to evaluate the dimensionality, reliability, and validity of the IIEF with a large sample of gay men. One thousand and eighteen men self-identifying as "exclusively gay" completed an online survey consisting of demographics, the IIEF, the Hospital Anxiety and Depression Scale (HADS), the Perceived Stress Scale 4 (PSS4), and the Gay Male Sexual Difficulties (GMSD) erectile difficulties sub-scale. The replicability of the IIEF factor structure with a gay male sample was determined using exploratory and confirmatory factor analyses. Additionally, the HADS, PSS4, and GMSD were used to determine the validity of the IIEF. The current study was unable to replicate the IIEF factor structure. Four items required deletion and the factor solution differed from the original. Thus, reinterpretation of the latent variables was deemed necessary. Although the resultant 12-item IIEF evidenced model fit, validity, and reliability, it is not recommended for use with gay men. The revised IIEF is unable to accurately measure gay men's erectile functioning as the content of the items fail to capture their sexual behaviors (i.e., insertive and receptive anal sex).

Duration of safe apnea in patients with morbid obesity during passive oxygenation using high-flow nasal insufflation versus regular flow nasal insufflation, a randomized trial.

BACKGROUND: Obese patients are at risk for rapid oxygen desaturation during anesthesia induction. Apneic oxygenation with regular flow oxygen insufflation has successfully been used to prolong the duration of safe apnea without desaturation (DAWD) in morbidly obese patients. Using high-flown nasal insufflation of oxygen (HFNI) for apneic oxygenation might further increase the DAWD. OBJECTIVES: To compare the duration of safe apnea using high-flown nasal insufflation of oxygen or standard flow oxygen insufflation for apneic oxygenation in a simulated difficult intubation scenario in patients with morbid obesity. SETTING: Operating room, University Hospital, Austria. METHODS: In a prospective, randomized, clinical trial, patients received standardized preoxygenation and anesthesia induction. Apneic oxygenation was performed using standard nasal prongs (10 L/min) or HFNI (120 L/min) during laryngoscopy. A Cormack-Lehane 3° view was maintained until the oxygen saturation on pulse oximetry (SpO2) dropped ≤95% or for a maximum of 15 minutes. The primary outcome of this study was to compare the duration of safe apnea using HFNI or standard flow oxygen insufflation for apneic oxygenation. In addition, arterial blood gas results, and airway pressures were investigated. RESULTS: In 40 patients with morbid obesity (body mass index [BMI] >40 kg/m2) and the American Society of Anesthesiologists physical classification ≤3 who underwent bariatric surgery, the median duration of safe apnea was 601 (268-900) seconds in the standard group and 537 (399-808) seconds in the HFNI group (P = .698). No differences in arterial blood gas results were observed between the groups. The median airway pressure was 0 (0-0) cm H2O in the standard group and 1 (0-2) cm H2O in the HFNI group (P = .005). CONCLUSION: Compared with standard nasal apneic oxygenation, HFNI did not increase the duration of safe apnea in patients with morbid obesity. A significant but clinically negligible higher airway pressure was observed when using HFNI.

Comparison of echocardiographic and invasive measures of volaemia and cardiac performance in critically ill patients.

Echocardiographic measurements are used in critical care to evaluate volume status and cardiac performance. Mean systemic filling pressure and global heart efficiency measures intravascular volume and global heart function. This prospective study conducted in fifty haemodynamically stabilized, mechanically ventilated patients investigated relationships between static echocardiographic variables and estimates of global heart efficiency and mean systemic filling pressure. Results of univariate analysis demonstrated weak correlations between left ventricular end-diastolic volume index (r = 0.27, p = 0.04), right atrial volume index (rho = 0.31, p = 0.03) and analogue mean systemic filling pressure; moderate correlations between left ventricular ejection fraction (r = 0.31, p = 0.03), left ventricular global longitudinal strain (r = 0.36, p = 0.04), tricuspid annular plane systolic excursion (rho = 0.37, p = 0.01) and global heart efficiency. No significant correlations were demonstrated by multiple regression. Mean systemic filling pressure calculated with cardiac output measured by echocardiography demonstrated good agreement and correlation with invasive techniques (bias 0.52 ± 1.7 mmHg, limits of agreement -2.9 to 3.9 mmHg, r = 0.9, p < 0.001). Static echocardiographic variables did not reliably reflect the volume state as defined by estimates of mean systemic filling pressure. The agreement between static echocardiographic variables of cardiac performance and global heart efficiency lacked robustness. Echocardiographic measurements of cardiac output can be reliably used in calculation of mean systemic filling pressure.

The impact of a high-quality basic life support police-based first responder system on outcome after out-of-hospital cardiac arrest.

BACKGROUND: Laypersons' efforts to initiate basic life support (BLS) in witnessed Out-of-Hospital Cardiac Arrest (OHCA) remain comparably low within western society. Therefore, in order to shorten no-flow times in cardiac arrest, several police-based first responder systems equipped with automated external defibrillators (Pol-AED) were established in urban areas, which subsequently allow early BLS and AED administration by police officers. However, data on the quality of BLS and AED use in such a system and its impact on patient outcome remain scarce and inconclusive. METHODS: A total of 85 Pol-AED cases were randomly assigned to a gender, age and first rhythm matched non-Pol-AED control group (n = 170) in a 1:2 ratio. Data on quality of BLS were extracted via trans-thoracic impedance tracings of used AED devices. RESULTS: Comparing Pol-AED cases and the control group, we observed a similar compression rate per minute (p = 0.677) and compression ratio (p = 0.651), mirroring an overall high quality of BLS administered by police officers. Time to the first shock was significantly shorter in Pol-AED cases (6 minutes [IQR: 2-10] vs. 12 minutes [IQR: 8-17]; p<0.001). While Pol-AED was not associated with increased sustained return of spontaneous circulation (p = 0.564), a strong and independent impact on survival until hospital discharge (adj. OR: 1.85 [95%CI: 1.06-3.23; p = 0.030]) and a borderline significance for the association with favorable neurological outcome (adj. OR: 1.58 [95%CI: 0.96-2.89; p = 0.052) were observed. CONCLUSION: We were able to demonstrate an early start and a high quality of BLS and AED use in Pol-AED assessed OHCA cases. Moreover, the presence of Pol-AED care was associated with better patient survival and borderline significance for favorable neurological outcome.

Cholecystitis after trauma.

BACKGROUND: The goal of this project was to investigate incidence, risk factors, histologic findings, and mortality rate of posttraumatic cholecystitis requiring surgical treatment. METHODS: Retrospective analysis of all patients admitted to the intensive care unit of an urban trauma center between April 1998 and January 2005. Data from the hospital and intensive care documentation systems databases and patients' charts were reviewed. All patients with cholecystitis treated by cholecystectomy were selected for further study. Potential risk factors, diagnostic, and histologic findings were analyzed. RESULTS: Cholecystitis was a fairly frequent finding in critically ill trauma patients (67 of 2,625 patients, 2.6%). Almost 10% of the patients with severe multiple injuries developed cholecystitis. Histologic findings showed a wide variation; three main diagnoses were established: acute acalculous cholecystitis (n = 28), chronic acalculous cholecystitis (n = 25), and cholecystitis with cholecystolithiasis (n = 13). Patients with acute acalculous cholecystitis and chronic acalculous cholecystitis were significantly younger and had significantly higher injury severity scores than patients with either cholecystitis with cholecystolithiasis or without cholecystitis. Noninvasive diagnostic tools such as ultrasonographic signs and laboratory data did not correlate with histologic diagnosis. Well-timed cholecystectomy within 24 hours after clinical suspicion lead to a 4.4% mortality rate in this group of patients. CONCLUSION: Cholecystitis after trauma is not a uniform disease. Although trauma severity seems to play an important role in the development or exacerbation of acalculous cholecystitis or both, cholecystolithiasis may play a significant role in patients with moderate to minor trauma. Intensivists should be aware of this complication in critically ill trauma patients because it seems to occur more frequently than previously assumed. Diagnosis can only be made if clinical signs, laboratory data, and ultrasonographic findings are taken into consideration. If posttraumatic cholecystitis is treated in an early stage by cholecystectomy, mortality rate remains low.