Mark Deshur

Desflurane-mediated Sympathetic Activation Occurs in Humans Despite Preventing Hypotension and Baroreceptor Unloading

Background Increasing concentrations of desflurane result in progressive decreases in blood pressure (BP) and, unlike other currently marketed, potent volatile anesthetics, heightened sympathetic nervous system activity. This study aimed to determine whether baroreflex mechanisms are involved in desflurane‐mediated sympathetic excitation. Methods Healthy volunteers were anesthetized with desflurane (n = 8) or isoflurane (n = 9). Heart rate (HR; measured by electrocardiograph), blood pressure (BP; measured by arterial catheter), and efferent sympathetic nerve activity (SNA; obtained from percutaneous recordings from the peroneal nerve) were monitored. Baroreflex sensitivity was evaluated at baseline while volunteers were conscious and during 0.5, 1, and 1.5 minimum alveolar concentration (MAC) anesthesia via bolus injections of nitroprusside (100 micro gram) and phenylephrine (150 micro gram) to decrease and increase BP. To prevent the BP decline with increasing depths of anesthesia, phenylephrine was infused to maintain mean BP at the 0.5 MAC level. Results The HR, BP, and SNA were similar between the groups at the conscious baseline measurement. Efferent SNA did not change during higher MAC of isoflurane, but it increased progressively as desflurane concentrations were increased beyond 0.5 MAC, despite maintaining BP at the 0.5 MAC value with phenylephrine infusions (P < 0.05). Cardiac baroslopes (based on changes in HR) were progressively and similarly decreased with increasing concentrations of isoflurane and desflurane (P < 0.05). Sympathetic baroslopes (based on SNA) decreased with increasing isoflurane concentrations but were maintained with increasing concentrations of desflurane; the response was significantly different between groups. Conclusions The increase in basal levels of SNA with increasing concentrations of desflurane persisted despite “fixing” BP and thus is probably not due to hypotension and unloading of the baroreceptors. Further, the preservation of reflex increases in SNA to nitroprusside during desflurane indicates that desflurane preserves one component of the baroreflex in humans when BP is “fixed.”

Neostigmine Administration after Spontaneous Recovery to a Train-of-Four Ratio of 0.9 to 1.0: A Randomized Controlled Trial of the Effect on Neuromuscular and Clinical Recovery

Background: When a muscle relaxant is administered to facilitate intubation, the benefits of anticholinesterase reversal must be balanced with potential risks. The aim of this double-blinded, randomized noninferiority trial was to evaluate the effect of neostigmine administration on neuromuscular function when given to patients after spontaneous recovery to a train-of-four ratio of 0.9 or greater. Methods: A total of 120 patients presenting for surgery requiring intubation were given a small dose of rocuronium. At the conclusion of surgery, 90 patients achieving a train-of-four ratio of 0.9 or greater were randomized to receive either neostigmine 40 &mgr;g/kg or saline (control). Train-of-four ratios were measured from the time of reversal until postanesthesia care unit admission. Patients were monitored for postextubation adverse respiratory events and assessed for muscle strength. Results: Ninety patients achieved a train-of-four ratio of 0.9 or greater at the time of reversal. Mean train-of-four ratios in the control and neostigmine groups before reversal (1.02 vs. 1.03), 5u2009min postreversal (1.05 vs. 1.07), and at postanesthesia care unit admission (1.06 vs. 1.08) did not differ. The mean difference and corresponding 95% CI of the latter were −0.018 and −0.046 to 0.010. The incidences of postoperative hypoxemic events and episodes of airway obstruction were similar for the groups. The number of patients with postoperative signs and symptoms of muscle weakness did not differ between groups (except for double vision: 13 in the control group and 2 in the neostigmine group; P = 0.001). Conclusions: Administration of neostigmine at neuromuscular recovery was not associated with clinical evidence of anticholinesterase-induced muscle weakness.

Successful resuscitation of a patient who developed cardiac arrest from pulsed saline bacitracin lavage during thoracic laminectomy and fusion

A patient with a history of T12 burst fracture caused by a fall, and with progressive weakness and sensory loss in the left leg, survived a cardiac arrest after pulsed saline bacitracin lavage irrigation during a posterior spinal fusion.

Increasing compliance with the World Health Organization Surgical Safety Checklist—a regional health system's experience

BACKGROUNDnIn 2009, NorthShore University HealthSystem adapted the World Health Organization Surgical Safety Checklist (SSC) at each of its 4 hospitals. Despite evidence that SSC reduces intraoperative mistakes and increase patient safety, compliance was found to be low with the paper form. In November 2013, NorthShore integrated the SSC into the electronic health record (EHR). The aim was to increase communication between operating room (OR) personnel and to encourage best practices during the natural workflow of surgeons, anesthesiologists, and nurses. The purpose of this study was to examine the impact of an electronic SSC on compliance and patient safety.nnnMETHODSnAn anonymous OR observer selected cases at random and evaluated the compliance rate before the rollout of the electronic SSC. In June 2014, an electronic audit was performed to assess the compliance rate. Random OR observations were also performed throughout the summer in 2014. Perioperative risk events, such as consent issues, incorrect counts, wrong site, and wrong procedure were compared before and after the electronic SSC rollout. A perception survey was also administered to NorthShore OR personnel.nnnRESULTSnCompliance increased from 48% (n = 167) to 92% (n = 1,037; P < .001) after the SSC was integrated into the electronic health record. Surgeons (91% vs 97%; P < .001), anesthesiologists (89% vs 100%; P < .001), and nurses (55% vs 93%; P < .001) demonstrated an increase in compliance. A comparison between risk events in the pre- and post-rollout period showed a 32% decrease (P < .01). Hospital-wide indicators including length of stay and 30-day readmissions were lower. In a survey to assess the OR personnels perceptions of the new checklist, 76% of surgeons, 86% of anesthesiologists, and 88% of nurses believed the electronic SSC will have a positive impact on patient safety.nnnCONCLUSIONSnThe World Health Organization SSC is a validated tool to increase patient safety and reduce intraoperative complications. The electronic SSC has demonstrated an increased compliance rate, a reduced number of risk events, and most OR personnel believe it will have a positive impact on patient safety.

Procedural Timeout Compliance Is Improved With Real-Time Clinical Decision Support.

Purpose The goal of this study was to assess compliance with a presurgical safety checklist before and after the institution of a surgical flight board displaying a surgical safety checklist with embedded real-time clinical decision support (CDS). We hypothesized that the institution of a surgical flight board with embedded real-time data support would improve compliance with the presurgical safety checklist. Methods In this prospective, observational trial, surgeon-led procedural timeout compliance for 300 procedures was studied. In phase I (PI), procedural timeouts were performed using a simple paper checklist. In phase II (PII), an electronic surgical flight board with an embedded safety checklist was installed in each operating room, but the timeout procedure consisted of the same paper process as in PI. In phase III (PIII), the flight board safety checklist was used. Ten procedures each from 10 surgeons were evaluated in each phase. Compliance was scored on a 12-point scale with each point representing a different item on the checklist. Results Timeout compliance in PI ranged from 4.5 to 8.6 and 8.75 to 12 in PIII. All 10 surgeons demonstrated statistically improved compliance from PI to PIII. Compliance was significantly improved in 8 of 12 safety check items. Decreased compliance was not seen with any checklist item. Of the items with CDS, compliance with procedure consent and special safety precautions improved from PI to PIII, as did compliance with display of essential imaging, critical events or concerns, and number of procedures (i.e., >1 surgeon performing procedures). Conclusions Using the electronic medical record with real-time CDS improves compliance with presurgical safety checklists.

Clinical Effectiveness and Safety of Intraoperative Methadone in Patients Undergoing Posterior Spinal Fusion Surgery: A Randomized, Double-blinded, Controlled Trial

Background: Patients undergoing spinal fusion surgery often experience severe pain during the first three postoperative days. The aim of this parallel-group randomized trial was to assess the effect of the long-duration opioid methadone on postoperative analgesic requirements, pain scores, and patient satisfaction after complex spine surgery. Methods: One hundred twenty patients were randomized to receive either methadone 0.2u2009mg/kg at the start of surgery or hydromorphone 2u2009mg at surgical closure. Anesthetic care was standardized, and clinicians were blinded to group assignment. The primary outcome was intravenous hydromorphone consumption on postoperative day 1. Pain scores and satisfaction with pain management were measured at postanesthesia care unit admission, 1 and 2u2009h postadmission, and on the mornings and afternoons of postoperative days 1 to 3. Results: One hundred fifteen patients were included in the analysis. Median hydromorphone use was reduced in the methadone group not only on postoperative day 1 (4.56 vs. 9.90u2009mg) but also on postoperative days 2 (0.60 vs. 3.15u2009mg) and 3 (0 vs. 0.4u2009mg; all P< 0.001). Pain scores at rest, with movement, and with coughing were less in the methadone group at 21 of 27 assessments (all P = 0.001 to < 0.0001). Overall satisfaction with pain management was higher in the methadone group than in the hydromorphone group until the morning of postoperative day 3 (all P = 0.001 to < 0.0001). Conclusions: Intraoperative methadone administration reduced postoperative opioid requirements, decreased pain scores, and improved patient satisfaction with pain management.

Documentation and Treatment of Intraoperative Hypotension: Electronic Anesthesia Records versus Paper Anesthesia Records

In this study, we examined anesthetic records before and after the implementation of an electronic anesthetic record documentation (AIMS) in a single surgical population. The purpose of this study was to identify any inconsistencies in anesthetic care based on handwritten documentation (paper) or AIMS. We hypothesized that the type of anesthetic record (paper or AIMS) would lead to differences in the documentation and management of hypotension. Consecutive patients who underwent esophageal surgery between 2009 and 2014 by a single surgeon were eligible for the study. Patients were grouped in to ‘paper’ or ‘AIMS’ based on the type of anesthetic record identified in the chart. Pertinent patient identifiers were removed and data collated after collection. Predetermined preoperative and intraoperative data variables were reviewed. Consecutive esophageal surgery patients (Nxa0=xa0189) between 2009 and 2014 were evaluated. 92 patients had an anesthetic record documented on paper and 97 using AIMS. The median number of unique blood pressure recordings was lower in the AIMS group (median (Q1,Q3) AIMS 30.0 (24.0, 39.0) vs. Paper 35.0 (28.5, 43.5), pxa0<xa00.01). However, the median number of hypotensive events (HTEs) was higher in the AIMS group (median (Q1,Q3) 8.0 (4.0, 18.0) vs. 4.0 (1.0, 10.5), pxa0<xa00.001), and the percentage of HTEs per blood pressure recording was higher in the AIMS group (30.4 ((Q1, Q3) (9.5, 60.9)% vs. 12.5 (2.4, 27.5)%), pxa0<xa00.01). Multivariable regression analysis identified independent predictors of HTEs. The incidence of HTEs was found to increase with AIMS (IRRxa0=xa01.88, pxa0<xa00.01). Preoperative systolic blood pressure, increased blood loss, and phenylephrine. A phenylephrine infusion was negatively associated with hypotensive events (IRRxa0=xa00.99, pxa0=xa00.03). We noted an increased incidence of HTEs associated with the institution of an AIMS. Despite this increase, no change in medical therapy for hypotension was seen. AIMS did not appear to have an effect on the management of intraoperative hypotension in this patient population.