Republished paper: Improving safety culture on adult medical units through multidisciplinary teamwork and communication interventions: the TOPS Project.

AIM: The goal of this project was to improve unit-based safety culture through implementation of a multidisciplinary (pharmacy, nursing, medicine) teamwork and communication intervention. METHOD: The Agency for Healthcare Research and Quality Hospital Survey on Patient Safety Culture was used to determine the impact of the training with a before-after design. RESULTS: Surveys were returned from 454 healthcare staff before the training and 368 staff 1 year later. Five of eleven safety culture subscales showed significant improvement. Nurses perceived a stronger safety culture than physicians or pharmacists. CONCLUSION: While it is difficult to isolate the effects of the team training intervention from other events occurring during the year between training and postevaluation, overall the intervention seems to have improved the safety culture on these medical units.

Improving safety culture on adult medical units through multidisciplinary teamwork and communication interventions: the TOPS Project.

AIM: The goal of this project was to improve unit-based safety culture through implementation of a multidisciplinary (pharmacy, nursing, medicine) teamwork and communication intervention. METHOD: The Agency for Healthcare Research and Quality Hospital Survey on Patient Safety Culture was used to determine the impact of the training with a before-after design. RESULTS: Surveys were returned from 454 healthcare staff before the training and 368 staff 1 year later. Five of eleven safety culture subscales showed significant improvement. Nurses perceived a stronger safety culture than physicians or pharmacists. CONCLUSION: While it is difficult to isolate the effects of the team training intervention from other events occurring during the year between training and postevaluation, overall the intervention seems to have improved the safety culture on these medical units.

The autodiagnostic pacemaker.

Loss of normal pacemaker stimulation and/or sensing functions requires prompt detection, automatic correction, and automatic and continuous "marking" of the intermittent failure. The autodiagnostic pacemaker (ADP) detects "failure to capture" (FC) by distinguishing, at its single stimulating and sensing electrode, between the normal biphasic cardiac response evoked by an adequate stimulus (corresponding to the QRS and T waves on the surface cardiogram) and the monophasic pseudo-response generated by electrotonic spread of a subthreshold stimulating current. Detection of "failure to sense" (FS) spontaneous cardiac activity requires two amplifiers: a "timing control" amplifier of standard fidelity and standard (approximately 250 ms) refractory period, and a second amplifier which has negligible refractoriness and provides high fidelity amplification of all evoked and spontaneous activity. Failure to sense (FS) is defined as a specified number of consecutive failures to recycle correctly the pacemaker's timing circuits. Similarly, a specified number of consecutive failures of the stimulus to evoke an active cardiac response is defined as a failure to capture (FC). When FC is detected, the ADP doubles the applied stimulus voltage and generates marker pulses which follow every subsequent stimulus by 40 ms. The marker pulses appear on the surface electrocardiogram, serving as an externally detectable "memory" of the earlier, possible corrected, failure. When FS is detected, non-stimulating marker pulses, of a different time relation (80 ms delay) to each stimulus, are generated continually and can also be detected externally. The ADP has been tested in 14 anesthetized, open-chest dogs. Unipolar rather than bipolar electrodes were used as they rpovided more reliable stimulation and more satisfactory electrograms for detection.

Chemically mediated transmission at a giant fiber synapse in the central nervous system of a vertebrate.

The hatchetfish, Gasteropelecus, possesses large pectoral fin adductor muscles whose simultaneous contraction enables the fish to dart upwards at the approach of a predator. These muscles can be excited by either Mauthner fiber. In the medulla, each Mauthner fiber forms axo-axonic synapses on four "giant fibers," two on each side of the midline. Each pair of giant fibers innervates ipsilateral motoneurons controlling the pectoral fin adductor muscles. Mauthner fibers and giant fibers can be penetrated simultaneously by microelectrodes close to the synapses between them. Electrophysiological evidence indicates that transmission from Mauthner to giant fiber is chemically mediated. Under some conditions miniature postsynaptic potentials (PSP's) are observed, suggesting quantal release of transmitter. However, relatively high frequency stimulation reduces PSP amplitude below that of the miniature potentials, but causes no complete failures of PSP's. Thus quantum size is reduced or postsynaptic membrane is desensitized. Ramp currents in Mauthner fibers that rise too slowly to initiate spikes can evoke responses in giant fibers that appear to be asynchronous PSP's. Probably both spikes and ramp currents act on the same secretory mechanism. A single Mauthner fiber spike is followed by prolonged depression of transmission; also PSP amplitude is little affected by current pulses that markedly alter presynaptic spike height. These findings suggest that even a small spike releases most of an immediately available store of transmitter. If so, the probability of release by a single spike is high for any quantum of transmitter within this store.

A rectifying electrotonic synapse in the central nervous system of a vertebrate.

The adductor muscles of the pectoral fins of the hatchetfish Gasteropelecus are innervated by bilateral pools of about 40 motoneurons which lie primarily in the first spinal segment. A pair of giant fibers on each side of the medulla send processes ventroposteriorly to the motoneuron pools. Electrophysiological evidence indicates that giant fibers are presynaptic to ipsilateral motoneurons, but not to contralateral ones. Transmission across the giant fiber, motoneuron synapse is electrically mediated as is indicated by direct measurement of electrotonic spread in either direction across the synapse, and by the extremely short latency of the giant fiber postsynaptic potentials (PSP's) in the motoneuron. The coupling resistance across the synapse was calculated from measurements of input and transfer resistance. The coupling resistance rectifies in such a way as to facilitate spread of depolarization from giant fiber to motoneuron, and to oppose transmission in the opposite direction. As a consequence of rectification, the giant fiber PSP in a motoneuron is augmented by hyperpolarization of the motoneuron. The coupling resistance calculated on the basis of this effect is in good agreement with calculations from input and transfer resistance data. Rectification at the electrotonic synapses may permit the motoneurons to act in small swimming movements as well as to fire synchronously in an extremely fast escape reflex mediated by Mauthner and giant fibers.