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Objective: To determine the proximity of neurovascular structures to multiplanar distal interlocking screws and proximal interlocking devices for an antegrade inserted humeral nail., Methods: Humeral nails (Depuy Synthes Humeral Nail-EX, Paoli, PA) were inserted into 10 matched cadavers with 3 distal interlocking trajectories: anterior to posterior (A-P), anterolateral to posteromedial, and anteromedial to posterolateral (AM-PL). The distance of the screw path and screw head to the radial, lateral antebrachial cutaneous nerve (LACN), and median nerves and the brachial artery was measured. Proximally, the distance of spiral blades and/or interlocking screws to the axillary nerve was measured., Results: The median distance of the screw path/screw head inserted (A-P) to the LACN was 0 mm/0 mm in the left arm and 3.5 mm/1.6 mm in the right arm. The median distance of the screw path/screw head inserted AM-PL to the median nerve was 7.08 mm/0 mm in the left arm and 0 mm/0.12 mm in the right arm. The median distance of the screw path/screw head inserted AM-PL to the brachial artery was 4.05 mm/3.83 mm in the left arm and 2.19 mm/2.84 mm in the right arm. The humeral head was radiographically divided into 3 zones. The average distances of the axillary nerve to interlocking devices placed into zone 2 and zone 3 of the humeral head are 14.65 mm and 1.07 mm, respectively., Conclusions: When using the DePuy Synthes Humeral Nail-EX, AM-PL screws may risk the median nerve and brachial artery; thus, this trajectory is not recommended. The LACN may be at risk with A-P and to a lesser degree, anterolateral to posteromedial screws. Proximally, interlocking devices in zone 3 of the humeral head may risk the axillary nerve.

Error avoidance in medicine follows similar rules that apply within the design and operation of other complex systems. The error-reduction concepts that best fit the conduct of testing during intraoperative neuromonitoring are forgiving design (reversibility of signal loss to avoid/prevent injury) and system redundancy (reduction of false reports by the multiplication of the error rate of tests independently assessing the same structure). However, error reduction in intraoperative neuromonitoring is complicated by the dichotomous roles (and biases) of the neurophysiologist (test recording and interpretation) and surgeon (intervention). This "interventional cascade" can be given as follows: test → interpretation → communication → intervention → outcome. Observational and controlled trials within operating rooms demonstrate that optimized communication, collaboration, and situational awareness result in fewer errors. Well-functioning operating room collaboration depends on familiarity and trust among colleagues. Checklists represent one method to initially enhance communication and avoid obvious errors. All intraoperative neuromonitoring supervisors should strive to use sufficient means to secure situational awareness and trusted communication/collaboration. Face-to-face audiovisual teleconnections may help repair deficiencies when a particular practice model disallows personal operating room availability. All supervising intraoperative neurophysiologists need to reject an insular or deferential or distant mindset.

Objective: To compare the rates of attempted and successful instrumental births, intrapartum cesarean delivery, and subsequent perinatal and maternal morbidity before and after implementing a training intervention to arrest the decline in forceps competency among resident obstetricians., Methods: This retrospective cohort study examined all attempted instrumental births at Monash Health from 2005 to 2014. We performed an interrupted time-series analysis to compare outcomes of attempted instrumental births in 2005-2009 with those in 2010-2014., Results: There were 72,490 births from 2005 to 2014 at Monash Health, of which 8,789 (12%) were attempted instrumental vaginal births. After the intervention, rates of forceps births increased [autoregressive integrated moving average coefficient (β) 1.5, 95% confidence interval (CI) 1.03-1.96; P<.001], and vacuum births decreased (β -1.43, 95% CI -2.5 to -0.37; P<.01). Rates of postpartum hemorrhage decreased (β -1.3, 95% CI -2.07 to -0.49; P=.002) and epidural use increased (β 0.03, 95% CI 0.02-0.05; P<.001). There was no change in rates of unsuccessful instrumental births (β -0.39, 95% CI -3.03 to 2.43; P=.83), intrapartum cesarean delivery (β -0.29, 95% CI -0.55 to 0.14; P=.24), third- and fourth-degree tears (β -1.04, 95% CI -3.1 to 1.00; P=.32), or composite neonatal morbidity (β -0.18, 95% CI -0.38 to 0.02, P=.08). Unsuccessful instrumental births were more likely to be in nulliparous women (P<.001), less likely to have a senior obstetrician present (P<.001), be at later gestation (P<.001), and involved larger birth weight neonates (P<.001)., Conclusion: A policy of ensuring obstetric forceps competency before beginning vacuum training results in more forceps births, fewer postpartum hemorrhages, and no increase in third- and fourth-degree perineal injuries or episiotomies.

Both remote monitoring and nearby/available care models depend on waveform telemetry (a limited form of telemedicine) during intraoperative neurophysiological monitoring (IONM). These dominant models neither mandate preoperative patient contact nor assume co-practitioner collegiality. This review and commentary argues in favor of a routine, normative relationship between the patient and the IONM physician/professional (IONM-P). Similarly, normal collegial relations should be established and maintained over time between the IONM-P and fellow co-practitioners (the proceduralist and the anesthesiologist). This professional practice "upgrade" places the IONM-P in a much stronger bioethical position among peers (and third party reviewers of the field and its practices). This "upgrade" also improves the likelihood that correct context-driven decisions will be made by the co-practitioners (IONM-P, proceduralist, and anesthesiologist) during complex multimodality monitoring. Most current models of IONM can be accommodated by readily available telemedicine-mediated videoconferencing. Several lines of argument are used to support this "patient-centered care model" of IONM.

The present study examined the neuroprotective effects of choroid plexus isolated from adult rats and encapsulated within alginate microcapsules. In vitro, conditioned media from cultured choroid plexus produced a marked, dose-dependent protection of embryonic cortical neurons against serum deprivation-induced cell death. In vivo studies demonstrated that a one-hour middle cerebral artery occlusion in adult Wistar rats produced profound motor and neurological impairments 1-3 days after stroke. In contrast, stroke animals transplanted with encapsulated choroid plexus cells displayed a significant reduction in both motor and neurological abnormalities. Histological analysis 3 days post-transplantation revealed that choroid plexus transplants significantly decreased the volume of striatal infarction. This is the first report demonstrating the therapeutic potential of transplanted choroid plexus for stroke.

Background: The incidence and severity of infections are increased when Intralipid or Diprivan are administered to patients. Intralipid promotes infection, presumably by inhibiting the reticuloendothelial system, thereby suppressing the host's constitutive immunity, whereas Diprivan supposedly promotes infection by supporting bacterial growth and increasing the inoculating dose. This study considers whether bacterial replication alone in Intralipid and Diprivan adequately explains the increased risk of infection associated with these agents or whether other factors might also be involved., Methods: Staphylococcus aureus was cultured in 10% Intralipid or Diprivan at clinically relevant conditions or in Intralipid containing 0.005% (w/v) sodium EDTA, a current additive, to measure growth. To determine whether Intralipid affected infection, New Zealand white rabbits were injected intravenously with S. aureus with or without Intralipid. Twenty-four hours later, bacteria in lung, liver, spleen, and kidney tissues were enumerated., Results: S. aureus failed to grow in Diprivan or Intralipid containing 0.005% EDTA. Whereas S. aureus did replicate in plain Intralipid, growth was delayed until the bacteria conditioned the media. Once initiated, growth was slow at clinically relevant temperatures. The administration of Intralipid to rabbits significantly increased the recovery of staphylococci from the kidneys, P < 0.001, relative to the other tissues 24 h after an intravenous inoculation with S. aureus, compared with rabbits receiving S. aureus with no Intralipid., Conclusions: These results suggest that Diprivan, and possibly Intralipid, represent poor media for the growth of S. aureus and may promote infection through mechanisms other than increased inoculum size.

Patients with severe pulmonary embolism can suffer progressive hypercapnia refractory to supramaximal mechanical ventilation, and may require open-thoracic or transvenous emergency embolectomy in addition to anticoagulation and/or thrombolysis. The functional recovery of gas exchange would be signaled by an increase in pulmonary CO2 elimination and decrease in CO2 retention; such data could guide the course of operative embolectomy. Accordingly, we studied five chloralose-urethane anesthetized, mechanically ventilated dogs with open thoraces in which the right pulmonary arteries (RPAs) were reversibly occluded with cloth snares. After waiting for steady state, we abruptly released the snare to restore RPA perfusion and experimentally simulate resolution of pulmonary embolism. For 70 min we serially measure the CO2 volume exhaled per breath (VCO2,br), arterial, mixed venous, and end-tidal PCO2 (PACO2, PVCO2, PETCO2), cardiac output (QT), and the alveolar dead space fraction (VDalv/VTalv = [PaCO2 - PETCO2/PaCO2). RPA reperfusion caused VCO2,br to significantly and abruptly increase from 8.9 +/- 2.7 to 11.6 +/- 3.6 mL; 70 min later VCO2,br had returned to baseline. PaCO2 and PVCO2 steadily decreased during 70 min of RPA reperfusion. PETCO2 increased from 25 +/- 5 to 33 +/- 5 mm Hg immediately after RPA reperfusion, as VDalv/VTalv decreased from 54% +/- 10% to 32% +/- 12%, but PETCO2 was still significantly greater than baseline at 70 min of RPA reperfusion. QT did not significantly change. We conclude that intraoperative measurement of VCO2,br should immediately detect and follow the resolution of CO2 retention in the lung and peripheral tissues after RPA reperfusion. PETCO2 could not detect the decrease of VCO2,br back to baseline because PETCO2 does not measure exhaled volume or the PCO2 waveform.