Roy G. Soto

The efficacy and safety of pain management before and after implementation of hospital-wide pain management standards: is patient safety compromised by treatment based solely on numerical pain ratings?

Inadequate analgesia in hospitalized patients prompted the Joint Commission on Accreditation of Healthcare Organizations in 2001 to introduce standards that require pain assessment and treatment. In response, many institutions implemented treatment guided by patient reports of pain intensity indexed with a numerical scale. Patient safety associated with treatment of pain guided by a numerical pain treatment algorithm (NPTA) has not been examined. We reviewed patient satisfaction with pain control and opioid-related adverse drug reactions before and after implementation of our NPTA. Patient satisfaction with pain management, measured on a 1–5 scale, significantly improved from 4.13 to 4.38 (P < 0.001) after implementation of an NPTA. The incidence of opioid over sedation adverse drug reactions per 100,000 inpatient hospital days increased from 11.0 pre-NPTA to 24.5 post-NPTA (P < 0.001). Of these patients, 94% had a documented decrease in their level of consciousness preceding the event. Although there was an improvement in patient satisfaction, we experienced a more than two-fold increase in the incidence of opioid over sedation adverse drug reactions in our hospital after the implementation of NPTA. Most adverse drug reactions were preceded by a documented decrease in the patients level of consciousness, which emphasizes the importance of clinical assessment in managing pain.

Capnography accurately detects apnea during monitored anesthesia care

Apnea and airway obstruction are common during monitored anesthesia care (MAC). Because their early detection is essential, we sought to measure the efficacy of capnography as an indicator of apnea during MAC at a variety of oxygen flow rates compared with thoracic impedance. Anesthesia care providers using standard American Society of Anesthesiologists monitors were blinded to capnography and thoracic impedance monitoring. Ten (26%) of the 39 patients studied developed 20 s of apnea; none was detected by the anesthesia provider, but all were detected by capnography and impedance monitoring. There was no difference in detection rates between the two methods. Higher oxygen flow rates decreased the amplitude of the capnograph but did not interfere with apnea detection. This pilot study revealed that apnea of at least 20 s in duration may occur in every fourth patient undergoing MAC. Although these episodes were undetected by the anesthesia provider, they were reliably detected by both capnography and respiratory plethysmography. Monitoring of nasal end-tidal CO2 is an important way to improve safety in patients undergoing MAC.

A Randomized, Dose-Finding, Phase II Study of the Selective Relaxant Binding Drug, Sugammadex, Capable of Safely Reversing Profound Rocuronium-Induced Neuromuscular Block

BACKGROUND:The reversal of a deep neuromuscular blockade remains a significant clinical problem. Sugammadex, a modified &ggr;-cyclodextrin, encapsulates steroidal neuromuscular blocking drugs, promoting their rapid dissociation from nicotinic receptors. Sugammadex is the first drug that acts as a selective relaxant binding agent. METHODS:We enrolled 50 patients into a Phase II dose-finding study of the efficacy and safety of sugammadex. Subjects, anesthetized with nitrous oxide and propofol, were randomized to one of two doses of rocuronium (0.6 or 1.2 mg/kg) and to one of five doses of sugammadex (0.5, 1.0, 2.0, 4.0, or 8.0 mg/kg). Neuromuscular monitoring was performed using the TOF Watch SX® acceleromyograph. Recovery was defined as a train-of-four ratio ≥0.9. Sugammadex was administered during profound block when neuromuscular monitoring demonstrated a posttetanic count of one or two. RESULTS:Reversal of neuromuscular block was obtained after administration of sugammadex in all but the lowest dose groups (0.5–1.0 mg/kg) where several subjects could not be adequately reversed. At the 2 mg/kg dose all patients were reversed with sugammadex, but there was significant variability (1.8–15.2 min). Patient variability decreased and speed of recovery increased in a dose-dependent manner. At the highest dose (8 mg/kg), mean recovery time was 1.2 min (range 0.8–2.1 min). No serious adverse events were reported during this trial. CONCLUSIONS:Sugammadex was well tolerated and effective in rapidly reversing profound rocuronium-induced neuromuscular block. The mean time to recovery decreased with increasing doses. Profound rocuronium-induced neuromuscular block can be reversed successfully with sugammadex at doses ≥2 mg/kg.

ACUTE PAIN MANAGEMENT FOR PATIENTS UNDERGOING THORACOTOMY

Management of thoracotomy pain can be difficult, but the benefits of effective pain control are significant. A variety of modalities for treating postoperative pain after thoracotomy are available, including systemic opiates, regional analgesics, and new oral and parenteral agents. This work provides a review of the literature and recommendations for the clinician.

Communication in critical care environments: mobile telephones improve patient care.

Most hospital policies prohibiting the use of wireless devices cite reports of disruption of medical equipment by cellular telephones. There have been no studies to determine whether mobile telephones may have a beneficial impact on safety. At the 2003 meeting of the American Society of Anesthesiologists 7878 surveys were distributed to attendees. The five-question survey polled anesthesiologists regarding modes of communication used in the operating room/intensive care unit and experience with communications delays and medical errors. Survey reliability was verified using test-retest analysis and proportion agreement in a convenience sample of 17 anesthesiologists. Four-thousand-eighteen responses were received. The test-retest reliability of the survey instrument was excellent (Kappa = 0.75; 95% confidence interval, 0.56–0.94). Sixty-five percent of surveyed anesthesiologists reported using pagers as their primary mode of communications, whereas only 17% used cellular telephones. Forty-five percent of respondents who use pagers reported delays in communications compared with 31% of cellular telephone users. Cellular telephone use by anesthesiologists is associated with a reduction in the risk of medical error or injury resulting from communication delay (relative risk = 0.78; 95% confidence interval, 0.6234–0.9649). The small risks of electromagnetic interference between mobile telephones and medical devices should be weighed against the potential benefits of improved communication.

Successful Intraoperative Spinal Cord Monitoring During Scoliosis Surgery Using a Total Intravenous Anesthetic Regimen Including Dexmedetomidine

Summary: Intraoperative neurophysiological monitoring (IONM) during corrective spinal surgery is widely used. Because of the possible interference with the recording of evoked potentials by inhalational anesthetics, total intravenous anesthetic (TIVA) regimens have been advocated. TIVA regimens may be difficult to use in pediatric populations due to metabolic factors. We report on the results of multimodality IONM during 18 cases in which a TIVA regimen incorporating dexmedetomidine (Precedex, Hespira, Lake Forest, IL) was used. Monitoring techniques included sensory (SSEP) and motor evoked potentials (MEP), as well as pedicle screw stimulation. SSEPs were maintained within an acceptable range of baseline amplitude (50%) and latency (10%), and MEPs remained elicitable throughout each case. We therefore found that the anesthetic regimen did not significantly interfere with any of the monitoring modalities used and conclude that IONM in the presence of dexmedetomidine is feasible under appropriate conditions.

The effect of addition of nitrous oxide to a sevoflurane anesthetic on BIS, PSI, and entropy

Objective. N2O is a commonly used anesthetic that has amnestic and analgesic properties. Recently, devices that estimate depth of consciousness have been introduced in an attempt to better titrate anesthesia, however the effect of N2O on these monitors is unclear. Methods. General anesthesia was induced and titrated to maintain normal blood pressure and pulse in healthy adults. Data were collected in three 10 minute intervals (Sevo, Sevo + N2O, Sevo). In Phase A, sevoflurane concentration was held constant during the N2O trial in 60 subjects monitored with either BIS, PSI, or Entropy. In Phase B, sevoflurane concentration was reduced as N2O was added, maintaining a constant overall “MAC” in 20 subjects monitored concurrently with BIS and Entropy. Sample size for both phases was designed to detect a 10 unit change in measure of processed EEG with alpha = .05 and statistical power = .80. Results. In Phase A, supplementing sevoflurane with > 65% N2O increased MAC from 1.3 ± 0.05 to 2.2 ± 0.10, but did not significantly alter BIS nor PSI (p-value for differential MAC is < 0.05). Entropy, however, dropped significantly, with a change in state entropy (SE) from 31.1 ± 7.3 to 18.9 ± 3.7 and a corresponding rise when N2O was discontinued. In Phase B, supplementing sevoflurane with > 65% N2O with a concomitant reduction in sevoflurane resulted in an increase in both BIS (from 34 ± 5 to 53.9 ± 11.5) and SE (from 32 ± 8.2 to 55.4 ± 21.3). Conclusion. Supplementing sevoflurane with > 65% N2O did not result in a significant change in either BIS or PSI when sevoflurane concentration was kept constant. Entropy, however, significantly decreased as anesthetic depth increased. When sevoflurane concentration was reduced during N2O administration, both BIS and Entropy rose despite maintenance of anesthetic depth, indicating a variable concentration effect between volatiles and N2O.

A comparison of bispectral index and entropy, or how to misinterpret both

Consciousness monitoring has become increasingly popular in general anesthesia cases, and a new technology has recently been introduced with potential advantages over the other available products. In this case report, we discuss a patient who was monitored simultaneously with Bispectral Index and Entropy and evaluate the differences between the two. More importantly, we emphasize the importance of vigilance when using new technologies and discuss the potential impact of lack of vigilance on patient outcome.

Organization of sensory input to the nociceptive-specific cutaneous trunk muscle reflex in rat, an effective experimental system for examining nociception and plasticity

Detailed characterization of neural circuitries furthers our understanding of how nervous systems perform specific functions and allows the use of those systems to test hypotheses. We have characterized the sensory input to the cutaneous trunk muscle (CTM; also cutaneus trunci [rat] or cutaneus maximus [mouse]) reflex (CTMR), which manifests as a puckering of the dorsal thoracolumbar skin and is selectively driven by noxious stimuli. CTM electromyography and neurogram recordings in naïve rats revealed that CTMR responses were elicited by natural stimuli and electrical stimulation of all segments from C4 to L6, a much greater extent of segmental drive to the CTMR than previously described. Stimulation of some subcutaneous paraspinal tissue can also elicit this reflex. Using a selective neurotoxin, we also demonstrate differential drive of the CTMR by trkA‐expressing and nonexpressing small‐diameter afferents. These observations highlight aspects of the organization of the CTMR system that make it attractive for studies of nociception and anesthesiology and plasticity of primary afferents, motoneurons, and the propriospinal system. We use the CTMR system to demonstrate qualitatively and quantitatively that experimental pharmacological treatments can be compared with controls applied either to the contralateral side or to another segment, with the remaining segments providing controls for systemic or other treatment effects. These data indicate the potential for using the CTMR system as both an invasive and a noninvasive quantitative assessment tool providing improved statistical power and reduced animal use. J. Comp. Neurol. 522:1048–1071, 2014.

Pediatric death: guidelines for the grieving anesthesiologist

This essay examines the effects of unexpected pediatric death on anesthesiology house staff, and offers a discussion of normal and abnormal patterns of grieving. The increased incidence of substance abuse and suicide among anesthesiologists is discussed, and the relationship of stress following patient death and appropriate coping skills is explored. A blueprint for managing stress is given based on a military combat stress model, and recommendations for residency training programs are made.