Intraoperative magnetic resonance imaging for cerebral cavernous malformations: When is it maybe worth it?

OBJECTIVE

Intraoperative magnetic resonance imaging (iMRI) can be useful for cerebral cavernous malformations (CCM) surgery. However, literature on this topic is scarce. We aim to investigate its clinical utility and propose criteria for the selection of patients who may benefit the most from iMRI.

METHODS

From 2017 to 2019, all patients with CCMs who required surgery assisted with iMRI were included in the study. Clinical and radiological features were analyzed. Outcome measures included the need for an immediate second-look resection and clinical course in early post-surgery -Timepoint 1- (Tp1) and at the 6-to-12-month follow-up -Timepoint2- (Tp2).

RESULTS

Out of 19 patients with 20 CCMs, 89% had bleeding in the past, and in 75% the CCM affected an eloquent area. According to the iMRI results, an immediate second-look resection was needed in 16% of them. In one patient, a remnant was not seen on iMRI. The mRS worsened in the immediate post-surgical exam (median, 1; IQR, 1) with improvements on the 6-month visit (median, 1; IQR, 2), (p = 0.018). When comparing the outcome of patients with and without symptoms at baseline, the latter fared better at Tp2 (p = 0.005).

CONCLUSIONS

iMRI is an intraoperative imaging tool that seems safe for CCM surgery and might reduce the risk of lesion remnants. In our series, it allowed additional revision for further resection in 16% of the patients. In our experience, iMRI may be especially useful for lesions in eloquent areas, those with a significant risk of brain shift and for large CCMs.

Informed Consent for Intraoperative Neural Monitoring in Thyroid and Parathyroid Surgery - Consensus Statement of the International Neural Monitoring Study Group

In the past decade, the use of intraoperative neural monitoring (IONM) in thyroid and parathyroid surgery has been widely accepted by surgeons as a useful technology for improving laryngeal nerve identification and voice outcomes, facilitating neurophysiological research, educating and training surgeons, and reducing surgical complications and malpractice litigation. Informing patients about IONM is not only good practice and helpful in promoting the efficient use of IONM resources but is indispensable for effective shared decision making between the patient and surgeon. The International Neural Monitoring Study Group (INMSG) feels complete discussion of IONM in the preoperative planning and patient consent process is important in all patients undergoing thyroid and parathyroid surgery. The purpose of this publication is to evaluate the impact of IONM on the informed consent process before thyroid and parathyroid surgery and to review the current INMSG consensus on evidence-based consent. The objective of this consensus statement, which outlines general and specific considerations as well as recommended criteria for informed consent for the use of IONM, is to assist surgeons and patients in the processes of informed consent and shared decision making before thyroid and parathyroid surgery.

Fine-needle aspiration with rapid parathyroid hormone assay to identify parathyroid gland in thyroidectomy

To determine the levels of parathyroid hormone (PTH) in the fluids of various tissues for identification of parathyroid glands during thyroidectomy.Our study comprised 31 patients with thyroid cancer who underwent lobectomy with central compartment dissection at our hospital from October 2014 to February 2015. A total of 186 tissue samples, including 28 from parathyroid glands and 158 from non-parathyroid tissues, were obtained during the operations. Tissue fluids were collected via fine-needle aspiration to measure PTH levels; the tissue was punctured 3 times with a 26-gauge syringe needle and washed with 0.5 mL normal saline. Tissues were also prepared for pathological examination.PTH concentrations were significantly higher in parathyroid tissues than non-parathyroid tissues. None of the patients had irremediable parathyroid dysfunction after surgical resection.Use of fine-needle aspiration for quantification of PTH levels in tissue fluids rapidly, safely, and effectively identifies the parathyroid glands during thyroidectomy.

Evaluating a Quality Improvement Initiative to Increase Anesthesia Providers' Use of and Understanding of Quantitative Neuromuscular Monitors

Improved understanding of the monitoring and dosing practices of anesthesia providers regarding neuromuscular blockade is necessary. The use of subjective methods such as peripheral nerve stimulation and clinical assessment tests can increase the risk of residual neuromuscular blockade and adverse postoperative outcomes. Quantitative monitoring of neuromuscular blockade is an alternative tool to peripheral nerve stimulation to guide neuromuscular blockade; however, it is rarely used by providers. We developed an initiative to improve anesthesia providers' knowledge of neuromuscular blockade pharmacology, physiology, monitoring, and management. After the initiative, an analysis assessed for practice change regarding the use of quantitative monitoring and dosing of neuromuscular blocking agents and neostigmine. The use of quantitative monitoring increased significantly from 14.0% in the preinitiative group to 48.0% after the initiative (P < .001). The least squares mean 95% effective dose (ED₉₅) neuromuscular blocking agents dose was compared between pre-initiative and postinitiative groups, and case length was a significant predictor for patients receiving the highest neuromuscular blocking agents doses. Neostigmine doses were compared between preinitiative and postinitiative groups, and body mass index was a significant predictor of the least squares mean neostigmine dose (P = .002) and the likelihood of receiving a high neostigmine dose (odds ratio = 0.911, 95% CI = 0.870-0.955).

Guidelines for Monitoring and Management of Pediatric Patients Before, During, and After Sedation for Diagnostic and Therapeutic Procedures

The safe sedation of children for procedures requires a systematic approach that includes the following: no administration of sedating medication without the safety net of medical/dental supervision, careful presedation evaluation for underlying medical or surgical conditions that would place the child at increased risk from sedating medications, appropriate fasting for elective procedures and a balance between the depth of sedation and risk for those who are unable to fast because of the urgent nature of the procedure, a focused airway examination for large (kissing) tonsils or anatomic airway abnormalities that might increase the potential for airway obstruction, a clear understanding of the medication's pharmacokinetic and pharmacodynamic effects and drug interactions, appropriate training and skills in airway management to allow rescue of the patient, age- and size-appropriate equipment for airway management and venous access, appropriate medications and reversal agents, sufficient numbers of appropriately trained staff to both carry out the procedure and monitor the patient, appropriate physiologic monitoring during and after the procedure, a properly equipped and staffed recovery area, recovery to the presedation level of consciousness before discharge from medical/dental supervision, and appropriate discharge instructions. This report was developed through a collaborative effort of the American Academy of Pediatrics and the American Academy of Pediatric Dentistry to offer pediatric providers updated information and guidance in delivering safe sedation to children.

Impact of intraoperative parathyroid hormone monitoring on the management of patients with primary hyperparathyroidism

BACKGROUND/OBJECTIVE

Intraoperative parathyroid hormone (IOPTH) monitoring during surgery for primary hyperparathyroidism (PHPT) could improve cure rate and simplify current care pathways. This study assesses the performance of US, MIBI and IOPTH monitoring and their impact on outcomes and perioperative strategy.

DESIGN

This is a retrospective study of a prospectively maintained database of patients who underwent parathyroidectomy guided by preoperative US, MIBI and IOPTH monitoring. Test performance (sensitivity, specificity, PPV, NPV, accuracy) and IOPTH added value (percentage of patients in whom test contributed to achieving cure) were calculated.

RESULTS

A total of 617 patients (median age 59 years, 75% females), 603 (97.7%) of them cured, were included in analysis. Sensitivity of US was higher than MIBI (78.2% vs 70%, P < 0.05), but both were inferior to IOPTH (98.6%, P < 0.05). US and MIBI were more sensitive at detecting single gland disease (SGD) than multigland disease (MGD) (85% vs 55% and 77.5% vs 45.5%, respectively, P < 0.05), while IOPTH performed well in both situations (98.8% vs 96.7%, P > 0.05). In 41 patients with incorrect US predictions, MIBI gave correct result only in 12 (29.3%) cases, while IOPTH gave correct predictions in all but one patient (97.6%). Minimally invasive parathyroidectomy (MIP) was completed in 409 patients, with a similar completion rate regardless whether both or one scan was positive. IOPTH added value was significant in whole cohort (14%) and in subgroups of patients with concordant vs discordant scans, minimally invasive vs conventional surgery, and initial vs reoperative surgery.

CONCLUSIONS

Intraoperative parathyroid hormone monitoring is more accurate at predicting cure than US and MIBI are at identifying abnormal glands in patients undergoing parathyroidectomy for PHPT and significantly contributes to cure rate in range of clinical scenarios. This implies that its routine use could facilitate successful surgery in patients with single positive imaging and increase number of MIPs while maintaining high cure rate.

[Intra-operative continuous non-invasive blood pressure monitoring]

Intra-operative hypotension is associated with increased risk of 30-day mortality and organ ischaemia. Thus, a reliable monitoring of blood pressure is desirable. New clinical studies indicate, that monitoring of middle arterial pressure with continuous non-invasive monitoring during stable haemodynamic conditioning provides accurate changes in blood pressure. The potential of continuous non-invasive monitoring is promising, but not fully developed.

The plethysmographic variability index does not predict fluid responsiveness estimated by esophageal Doppler during kidney transplantation: A controlled study

Research is ongoing to find a noninvasive method of monitoring, which can predict fluid responsiveness in patients undergoing kidney transplantation.To compare the responses to fluid challenges with the Pleth Variability Index, a noninvasive dynamic index derived from plethysmographic variability (Radical 7 pulse oximeter; Masimo Corporation, Irvine, CA), and the esophageal Doppler, the criterion standard.Observational study.University hospital; study from May 2011 and May 2012.Forty-eight patients with end-renal function were included and 44 analyzed. Patients with cardiac failure were not eligible.Fluid challenges were administered during maintenance of general anesthesia but before skin incision and repeated if the patient was deemed to be a "responder" (increase in stroke volume ≥10%).The primary endpoint was to assess if the Pleth Variability Index is an accurate predictor of fluid responsiveness.Among 76 fluid challenges, 38 were considered as positive (increase in stroke volume measured by Doppler ≥10%). Pleth Variability Index was similar at baseline between responders and nonresponder patients. Fluid challenges were associated with a significant decrease in Pleth Variability Index in overall cases (12 [8-14] vs 10 [6-17], P = .050), but it was not able to discriminate between responders (12 [8-15] vs 10 [5-15], P = .650) and nonresponders (11 [6-16] vs 8 [5-14], P = .047). The area under the Receiver Operating Characteristic curve for Pleth Variability Index was 0.49 (0.36-0.62).Pleth Variability Index is not an accurate predictor of fluid responsiveness during kidney transplantation.

Assessment of interchangeability rate between 2 methods of measurements: An example with a cardiac output comparison study

The Bland-Altman (BA) and percentage error (PE) methods have been previously described to assess the agreement between 2 methods of medical or laboratory measurements. This type of approach raises several problems: the BA methodology constitutes a subjective approach to interchangeability, whereas the PE approach does not take into account the distribution of values over a range. We describe a new methodology that defines an interchangeability rate between 2 methods of measurement and cutoff values that determine the range of interchangeable values. We used a simulated data and a previously published data set to demonstrate the concept of the method. The interchangeability rate of 5 different cardiac output (CO) pulse contour techniques (Wesseling method, LiDCO, PiCCO, Hemac method, and Modelflow) was calculated, in comparison with the reference pulmonary artery thermodilution CO using our new method. In our example, Modelflow with a good interchangeability rate of 93% and a cutoff value of 4.8 L min, was found to be interchangeable with the thermodilution method for >95% of measurements. Modelflow had a higher interchangeability rate compared to Hemac (93% vs 86%; P = .022) or other monitors (Wesseling cZ = 76%, LiDCO = 73%, and PiCCO = 62%; P < .0001). Simulated data and reanalysis of a data set comparing 5 CO monitors against thermodilution CO showed that, depending on the repeatability of the reference method, the interchangeability rate combined with a cutoff value could be used to define the range of values over which interchangeability remains acceptable.

Influence of non-invasive blood pressure measurement intervals on the occurrence of intra-operative hypotension

The American Society of Anesthesiologists Standards for Basic Monitoring recommends blood pressure (BP) measurement every 5 min. Research has shown distractions or technical factors can cause prolonged measurement intervals exceeding 5 min. We investigated the relationship between prolonged non-invasive BP (NIBP) measurement interval and the incidence of hypotension, detected post-interval. Our secondary outcome was to determine independent predictors of these prolonged NIBP measurement intervals. Retrospective data were analyzed from 139,509 general anesthesia cases from our institution's Anesthesia Information Management System (AIMS). Absolute hypotension (AH) was defined a priori as a systolic BP < 80 mmHg and relative hypotension (RH) was defined as a 40% decrease in systolic BP from the preoperative baseline. Odds ratios (OR) with 95% confidence intervals and Pearson's Chi square Test reported the association of prolonged NIBP measurement intervals on hypotension detected post-NIBP measurement interval. Logistic regression models were developed to determine independent predictors of NIBP measurement intervals. The analysis revealed that NIBP measurement intervals greater than 6 and 10 min are associated with an approximately four times higher incidence of a patient transitioning into hypotension (AH/RH > 6 min OR 4.0 / 3.6; AH/RH > 10 min OR 4.3 / 3.9; p < 0.001). A key finding was that the "> 10-minute AH model" indicated that age 41-80, increased co-morbidity profile, obesity and turning (repositioning) of the operative room table were significant predictors of prolonged NIBP measurement intervals (p < 0.001). While we do not suggest NIBP measurement intervals cause hypotension, intervals greater than 6 and 10 min are associated with a fourfold increase in the propensity of an undetected transition into both RH or AH. These data support current monitoring guidelines.

Impact of Stroke Therapy Academic Industry Roundtable (STAIR) Guidelines on Peri-Anesthesia Care for Rat Models of Stroke: A Meta-Analysis Comparing the Years 2005 and 2015

Numerous studies using rats in stroke models have failed to translate into successful clinical trials in humans. The Stroke Therapy Academic Industry Roundtable (STAIR) has produced guidelines on the rodent stroke model for preclinical trials in order to promote the successful translation of animal to human studies. These guidelines also underline the importance of anaesthetic and monitoring techniques. The aim of this literature review is to document whether anaesthesia protocols (i.e., choice of agents, mode of ventilation, physiological support and monitoring) have been amended since the publication of the STAIR guidelines in 2009. A number of articles describing the use of a stroke model in adult rats from the years 2005 and 2015 were randomly selected from the PubMed database and analysed for the following parameters: country where the study was performed, strain of rats used, technique of stroke induction, anaesthetic agent for induction and maintenance, mode of intubation and ventilation, monitoring techniques, control of body temperature, vascular accesses, and administration of intravenous fluids and analgesics. For each parameter (stroke, induction, maintenance, monitoring), exact chi-square tests were used to determine whether or not proportions were significantly different across year and p values were corrected for multiple comparisons. An exact p-test was used for each parameter to compare the frequency distribution of each value followed by a Bonferroni test. The level of significant set at < 0.05. Results show that there were very few differences in the anaesthetic and monitoring techniques used between 2005 and 2015. In 2015, significantly more studies were performed in China and significantly fewer studies used isoflurane and nitrous oxide. The most striking finding is that the vast majority of all the studies from both 2005 and 2015 did not report the use of ventilation; measurement of blood gases, end-tidal carbon dioxide concentration, or blood pressure; or administration of intravenous fluids or analgesics. The review of articles published in 2015 showed that the STAIR guidelines appear to have had no effect on the anaesthetic and monitoring techniques in rats undergoing experimental stroke induction, despite the publication of said guidelines in 2009.

Intraoperative nerve monitoring during thyroid surgery

PURPOSE OF REVIEW

Laryngeal nerve injury, resulting in speech and swallowing dysfunction, is a feared complication of thyroid operations. Routine visualization of the recurrent laryngeal nerve (RLN) has decreased the likelihood of nerve injury, and intraoperative nerve monitoring has been applied in the hope of further enhancing safety.

RECENT FINDINGS

There is conflicting evidence about the value of nerve monitoring during thyroid operations, despite ample research. The data favor nerve monitoring in certain situations, such as neck re-explorations, contralateral RLN injury, extensive or challenging dissections, invasive tumors or large goiters, and nonrecurrent or branching recurrent laryngeal nerves. Continuous intraoperative nerve monitoring may reduce the chances of excessive traction, which is the most common mechanism of injury. Nerve monitoring may also identify and protect the external branches of the superior laryngeal nerve.

SUMMARY

Surgeons should routinely identify recurrent laryngeal nerves during thyroid operations, and intraoperative nerve monitoring might be a useful adjunct to prevent injury. As a result of the relatively low probability of permanent recurrent laryngeal nerve injury, it is difficult to establish the absolute value of nerve monitoring. Further research may focus on continuous nerve monitoring and intraoperative monitoring of the external branches of the superior laryngeal nerves.

Prognostic Value of the Blink Reflex in Acoustic Neuroma Surgery

OBJECTIVE: The study goal was to demonstrate that blink reflex analysis can predict postoperative facial nerve outcome in cerebellopontine angle tumor surgery.

STUDY DESIGN, SETTING, AND PATIENTS: In an open and prospective study conducted at a single tertiary care center over 3 years, 91 subjects with a vestibular schwannoma filling the internal auditory meatus were enrolled and operated on via a translabyrinthine approach. The difference in latency of the early response (δR1) of the blink reflex between the pathologic side and the healthy side was calculated in every patient during a complete electrophysiologic examination of the facial nerve performed on the day before surgery.

MAIN OUTCOME MEASURES: δR1 was compared with the other preoperative data (tumor volume, facial function), with the perioperative observations (difficulties with the dissection of the facial nerve), and especially with the postoperative status after 1 year. The statistical study was conducted using polynomial regression.

RESULTS: Patients with a negative or zero δR1 have normal facial function at 1 year. For those with a positive δR1 the outcome is not favorable unless the tumor is small. For patients presenting with an immediate complete facial paralysis, the value of δR1 is also indicative of facial function outcome.

CONCLUSION: Statistical analysis shows that the blink reflex, through δR1, has an excellent prognostic value in anticipating the difficulties with facial nerve dissection and postoperative facial function after 1 year.

Comparison of false-negative/positive results of intraoperative evoked potential monitoring between no and partial neuromuscular blockade in patients receiving propofol/remifentanil-based anesthesia during cerebral aneurysm clipping surgery: A retrospective analysis of 685 patients

Although the elicited responses of motor evoked potential (MEP) monitoring are very sensitive to suppression by anesthetic agents and muscle relaxants, the use of neuromuscular blockade (NMB) during MEP monitoring is still controversial because of serious safety concerns and diagnostic accuracy. Here, we evaluated the incidence of unacceptable movement and compared false-negative MEP results between no and partial NMB during cerebral aneurysm clipping surgery. We reviewed patient medical records for demographic data, anesthesia regimen, neurophysiology event logs, MEP results, and clinical outcomes. Patients were divided into 2 groups according to the intraoperative use of NMB: no NMB group (n = 276) and partial NMB group (n = 409). We compared the diagnostic accuracy of MEP results to predict postoperative outcomes between both groups. Additionally, we evaluated unwanted patient movement during MEP monitoring in both groups. Of the 685 patients, 622 (90.8%) manifested no intraoperative changes in MEP and no postoperative motor deficits. Twenty patients showed postoperative neurologic deficits despite preserved intraoperative MEP. False-positive MEP results were 3.6% in the no NMB group and 3.9% in the partial NMB group (P = 1.00). False-negative MEP results were 1.1% in the no NMB group and 4.2% in the partial NMB group (P = 0.02). No spontaneous movement or spontaneous respiration was observed in either group. Propofol/remifentanil-based anesthesia without NMB decreases the stimulation intensity of MEPs, which may reduce the false-negative ratio of MEP monitoring during cerebral aneurysm surgery. Our anesthetic protocol enabled reliable intraoperative MEP recording and patient immobilization during cerebral aneurysm clipping surgery.

A Comparison of Gastric and Rectal CO₂ in Cardiac Surgery Patients

Critical care nurses assess and treat clinical conditions associated with inadequate oxygenation. Changes in regional organ (gut) blood flow are believed to occur in response to a decrease in oxygenation. Although the stomach is a widely accepted monitoring site, there are multiple methodological and measurement issues associated with the gastric environment that limit the accuracy of P CO2 detection. The rectum may provide nurses with an alternative site for monitoring changes in PCO2 without the limitations associated with gastric monitoring. This pilot study used a repeated measures design to examine changes in gastric and rectal PCO2 during elective coronary artery bypass grafting with cardiopulmonary bypass (CPB) and in the immediate 4-hr postoperative period in 26 subjects. The systemic indicators explained little variation in the regional indicators during protocol. A comparison of rectal and gastric PCO2 revealed no statistically significant differences in the direction or magnitude of change over any phase of cardiac surgery (baseline, CPB, post-CPB). A reduction in both rectal and gastric PCO2 occurred during CPB, and both values trended upward during the post-CPB phase. However, poor correlation and agreement was found between the measures of PCO2 at the two sites. Although clinically important, the cause is unclear. Possible explanations include variation in CO2 production between the gastric and rectal site, differences in sensitivity of the two monitoring instruments, or the absence of hemodynamic complications, which limited the extent of change in PCO2. Further investigation using patients with more profound changes in oxygenation are needed to identify response patterns and possible mechanisms.

[Indices of intraoperative flowmetry, determining patency of grafts in the remote period after revascularization of the right coronary artery]

The authors studied the threshold values of ultrasound flowmetry concerning composite T-grafts, combined I-grafts, and autovenous shunts during revascularization of the right coronary artery (RCA), determining high risk for the development of shunt occlusion in the remote postoperative period. The retrospective study included a total of 223 patients subjected to revascularization of the RCA's basin with the help of composite T-grafts, combined I-grafts, and autovenous shunts. Depending on the method of bypass grafting of the RCA and its branches, all patients were subdivided into 3 groups: Group 1 was composed of 65 patients in whom the RCA basin was revascularized by a branch of the composite T-graft, Group 2 comprised 112 patients who endured autovenous aortocoronary bypass grafting, and Group 3 consisted of 46 patients in whom the RCA basin was shunted by a combined mammarovenous I-graft. The groups had no statistically significant differences on the main clinical and demographic parameters. Intraoperative assessment of the blood flow through the coronary shunts was carried out by means of ultrasound flowmetry. The remote results were evaluated based on the findings of the control coronaroshuntography which was carried out in all patients within the terms varying from 16 to 43 months. In the remote period in Group 1 patients (T-graft), 59 (90%) mammary shunts were patent, in Group 2 - 99 (88.4%) autovenous shunts, and in Group 3 (I-graft) 42 (95.5%) shunt were patent. Cumulative probability of freedom from shunt occlusion within the terms up to 3 years after surgery in Group 1 amounted to 82±0.5%, in Group 2 to 58±2.1%, and in Group 3 to 86±1.9%, with the differences between Group 2 and other groups being statistically significant (p=0.01). The Poisson regression analysis showed that the risk for graft occlusion increased by 10% with the resistance index in the branch of the T-graft from 4.0; by 8% with the resistance index in the autovein from 2.9; and by 3% with the index of resistance in the I-graft from 3.2. The conclusion was made that composite T-grafts and combined I-grafts demonstrated similar results of patency within the terms up to 3 years, possessing advantages over autovenous conduits while shunting the RCA basin. The optimal index of peripheral resistance for the autovein during revascularization of the RCA basin is up to 2.9; for the combined T-graft - up to 3.2, and for the composite T-graft - up to 4.0. Probability of shunt occlusion in the remote period does not depend upon the average volumetric blood velocity (Q<inf>mean</inf>) but is directly proportional to the value of the pulsatility index (Pi) which reflects the state of the distal bed.

Vacuum-Assisted Venous Drainage: A 2014 Safety Survey

Despite the widespread use of vacuum-assisted venous drainage (VAVD) and case reports describing catastrophic incidents related to VAVD, there is a lack of data cataloging specific safety measures that individuals and institutions have incorporated into their VAVD practices for the prevention of these incidents. Therefore, the purpose of this study is to survey the perfusion community to gather data on VAVD practices, and to compare these current practices with literature recommendations and the American Society of ExtraCorporeal Technology (AmSECT) Standards and Guidelines. In September 2014, a survey was distributed via PerfList and PerfMail, and by direct e-mail to members of the New York State Society of Perfusionists, targeting certified clinical perfusionists in New York State. Survey topics pertaining to VAVD practice included 1) equipment, 2) pressure monitoring and alarms, 3) protocols, checklists, and documentation, and 4) VAVD-related incidents. Of ∼200 certified clinical perfusionists who live and/or work in New York State (NYS), 88 responded (42%). Most respondents (90.1%) report they use VAVD. Of these, 87.3% report that they monitor VAVD pressure, with 51.6% having audible and visual alarms for both positive and excessive negative pressures. At the institutional level, 61.2% of respondents reported that there is a protocol in place at for their team limiting negative pressure in the reservoir, 28.4% document VAVD pressure in the pump record, and AmSECT's three recommended VAVD checklist items are met with 53.7%, 55.1%, and 33.8% compliance. In conclusion, the results of this study reveal that the use of VAVD has increased and has become nearly universal in 2014. There is high compliance to some of the literature recommendations and AmSECT Standards and Guidelines, however, there are still some gaps between current practices and these recommendations. Continued improvement, both at the individual and institutional levels, will help to improve patient safety by preventing untoward events from occurring while using VAVD.

A Retrospective Study of the Impact of Intraoperative Intact Parathyroid Hormone Monitoring During Total Parathyroidectomy for Secondary Hyperparathyroidism: STARD Study

The study aimed to evaluate the diagnostic accuracy of intraoperative intact parathyroid hormone (IO-iPTH) in patients with secondary hyperparathyroidism (HPT). The cut-off for IO-iPTH monitoring remains unknown. This was a single-center retrospective review of 226 consecutive patients (107 males and 119 females) who underwent parathyroidectomy for secondary HPT between May 2010 and March 2014. The predetermined cut-off for IO-iPTH was a 70% IO-iPTH drop from baseline 10 minutes after total parathyroidectomy and thymectomy. We used <60 pg/mL iPTH value on postoperative day 1 (POD1) as an indicator of successful removal of parathyroid glands and reviewed the frequency of reoperation other than in autografted sites during the observation period. This study was based on the Standards for the Reporting of Diagnostic accuracy compliant. The reoperation rate in patients with >60 pg/mL iPTH value (POD1) was significantly higher than that in patients with <60 pg/mL iPTH value (POD1), (13.0% versus 0.5% P = 0.003). Sensitivity, specificity, and accuracy of >70% IO-iPTH drop were 97.5%, 52.2%, and 92.9%, respectively, this criterion was demonstrated to be beneficial in 26 patients. In 5 patients, <70% IO-iPTH drop was observed and further exploration enabled sufficient removal of parathyroid glands. In 21 patients, although fewer than 4 parathyroid glands were removed after enough explorations, >70% IO-iPTH drop enabled termination of operations and iPTH value (POD1) was <60 pg/mL.An iPTH value of <60 pg/mL (POD1) was a good predictor for successful parathyroidectomy. A 70% IO-iPTH drop from the baseline was appropriate to determine sufficient parathyroid gland removal during parathyroidectomy for patients with secondary HPT. [Corrected]

Update on a Quality Initiative to Standardize Perioperative Care for Continuous Subcutaneous Insulin Infusion Therapy

OBJECTIVE

The objective of the analysis was to review the effectiveness of a care process model (CPM) developed to guide management of patients on insulin pump therapy undergoing elective surgical procedures.

METHODS

Electronic medical records were reviewed to assess the impact of the CPM on documentation of insulin pump status, glucose monitoring, and safety during the perioperative phase of care. Post-CPM care was compared with management provided before CPM implementation.

RESULTS

We reviewed 45 cases on insulin pump therapy in the pre-CPM cohort and 106 in the post-CPM cohort. Demographic characteristics, categories of surgery, and perioperative times were not significantly different between the 2 groups. Recommended hemoglobin A1c monitoring occurred in 73% of cases in the pre-CPM cohort but improved to 94% in the post-CPM group (P < .01). There was a higher frequency of documentation of the insulin pump during the preoperative, intraoperative, and postanesthesia care unit segments of care in the post- vs pre-CPM periods (all P < .01). The number of cases with intraoperative glucose monitoring increased (57% pre-CPM vs 81% post-CPM; P < .01). Glycemic control was comparable between the 2 CPM periods. Hypoglycemia was rare, with only 3 episodes in the pre-CPM group and 4 in the post-CPM. No adverse events associated with perioperative insulin pump use were observed.

CONCLUSIONS

This analysis adds to previous data on use of insulin pump therapy during the perioperative period. Some processes require additional attention, but data continue to indicate that a standardized approach to care can lead to a successful and safe transition of insulin pump therapy throughout the perioperative period.

Performance of mobile digital X-ray fluoroscopy using a novel flat panel detector for intraoperative use

BACKGROUND

Technologies employing digital X-ray devices are developed for mobile settings.

OBJECTIVE

To develop a mobile digital X-ray fluoroscopy (MDF) for intraoperative guidance, using a novel flat panel detector to focus on diagnostics in outpatient clinics, operating and emergency rooms.

METHODS

An MDF for small-scale field diagnostics was configured using an X-ray source and a novel flat panel detector. The imager enabled frame rates reaching 30 fps in full resolution fluoroscopy with maximal running time of 5 minutes. Signal-to-noise (SNR), contrast-to-noise (CNR), and spatial resolution were analyzed. Stray radiation, exposure radiation dose, and effective absorption dose were measured for patients.

RESULTS

The system was suitable for small-scale field diagnostics. SNR and CNR were 62.4 and 72.0. Performance at 10% of MTF was 9.6 lp/mm (53 μ m) in the no binned mode. Stray radiation at 100 cm and 150 cm from the source was below 0.2 μ Gy and 0.1 μ Gy. Exposure radiation in radiography and fluoroscopy (5 min) was 10.2 μ Gy and 82.6 mGy. The effective doses during 5-min-long fluoroscopy were 0.26 mSv (wrist), 0.28 mSv (elbow), 0.29 mSv (ankle), and 0.31 mSv (knee).

CONCLUSIONS

The proposed MDF is suitable for imaging in operating rooms.

Management of dabigatran-induced bleeding: expert statement

The interdisciplinary group of experts has compiled a clinical guidance for manifest dabigatran-induced haemorrhage and envisaged invasive interventions on patients under dabigatran. It recommends an escalation of treatment measures as summarized in a pocket guide (see electronic supplementary material online and insert in the print issue).

A closer look at the standards for nurse anesthesia practice

As part of its ongoing work, the AANA's Practice Committee reviewed the Scope and Standards for Nurse Anesthesia Practice, particularly focusing on the Standards for Nurse Anesthesia Practice. Revisions and updates were made to the standards to ensure clarity and reflect current anesthesia practice. This article highlights several of the important revisions made to the Standards for Nurse Anesthesia Practice, specifically focusing on the importance of documentation, updates to Standard V-Patient Monitoring, and changes to other documents affected by the updates. This is not an exhaustive discussion of all changes made to the document. The updated Standards for Nurse Anesthesia Practice are presented in their entirety.

Quality assurance and performance improvement in intraoperative neurophysiologic monitoring programs

Quality assurance (QA) as it relates to intraoperative neurophysiological monitoring (IONM) can be defined as the systematic monitoring, evaluation, and modification of the IONM service to insure that desired standards of quality are being met. In practice, that definition is usually extended to include the concept that the quality of the IONM service will be improved wherever possible and, although there are some differences in the two terms, in this article the term QA will be understood to include quality improvement (QI) processes as well. The measurement and documentation of quality is becoming increasingly important to healthcare providers. This trend is being driven by pressures from accrediting agencies, payers, and patients. The essential elements of a QA program are described. A real-life example of QA techniques and management relevant to IONM providers is presented and discussed.

Safety and current achievements in thyroid surgery with neuromonitoring

One of the most important complications during thyroid surgery is injury to the recurrent laryngeal nerve (RLN) which leads to dysfunction and palsy of the vocal folds. Adequate knowledge about the location of the RLN supported by neuromonitoring can help the operating surgeon to prevent this complication. Visualisation of the nerve alone seems to not be enough. Much more important is an estimation of the function of the RLN. One can say that nowadays we are in the passing era (transition period) of only visualisation of the recurrent laryngeal nerve during operation and entering the era of its neuromonitoring. Neuromonitoring gives us information about the location and function of the RLN. Using this equipment, thyroid surgery becomes safer not only for the patients but also for the operating surgeon in the way of the medicolegal consequences of surgical complications.

Review article: the evolving role of information technology in perioperative patient safety

PURPOSE

The adoption of new technologies in medicine is frequently met with both enthusiasm and resistance. The universal adoption of health information technology (IT) and anesthesia information management systems (AIMS) remains low despite the potential benefits. Electronic medical records, and hence AIMS, are at the intersection of patient safety. This article highlights advantages and barriers to adoption and implementation of IT in general and AIMS in particular, with a focus on clinical decision support systems (CDSS) and computerized physician order entry (CPOE) as hallmarks that may lead to improvement in patient safety and quality in the perioperative setting.

PRINCIPAL FINDINGS

The advantages of health IT and AIMS include improved legibility of documentation; the ability to integrate new scientific evidence into practice; enhanced management and exchange of complex health information; the ability to standardize order sets, incorporate computerized physician order entry, and provide clinical decision support; and the ability to capture data for management, research, and quality monitoring and reporting. While not foolproof, AIMS have been shown to improve safety, quality, and patient outcomes. Barriers to the adoption of health IT and AIMS include costs, lack of truly interoperable AIMS components in health-system IT solutions, and lack of clinician involvement in implementation, planning, design, and installation of many IT or AIMS products.

CONCLUSIONS

Health IT and AIMS are at the intersection of patient safety and technology. Anesthesiologists are perfectly positioned to be the physician leaders of adoption, design, implementation, and integration, not only for AIMS but also for health-system IT solutions in general.

Can the Surgical Apgar Score predict morbidity and mortality in general orthopaedic surgery?

PURPOSE

The Surgical Apgar Score (SAS) is a simple tally based on intra-operative heart rate, blood pressure and blood loss; it predicts 30-day major postoperative complications and mortality in different surgical fields, but no validation has been performed in general orthopaedic surgery.

METHODS

A prospective assessment of the SAS in 723 consecutive patients undergoing major and intermediate orthopaedic procedures was performed in an 18-month period. The SAS was calculated immediately after surgery, and the occurrence of major complications or death was registered within a 30-day follow-up.

RESULTS

Thirty-seven patients had ≥1 complication (5.12 %). The complication rate did not augment as the score decreased (SAS 9-10 = 6.56 %; SAS 7-8 = 2.62 %; SAS 5-6 = 7.21 %; SAS ≤4 = 10.2 %), the relative risk did not augment as the score decreased and the likelihood ratio did not increase with decreasing SAS values, except in the subgroup of patients undergoing spine surgery. The C-statistic was 0.59 (95 % confidence interval 0.48-0.69), a weak discriminatory value. Using a threshold of 7 to define high-risk and low-risk patients, the SAS allowed risk stratification only for spine surgery.

CONCLUSIONS

The SAS does not predict 30-day major complications and death in patients undergoing general orthopaedic surgery, but it is useful in the subgroup of patients undergoing spine surgery.

A Preventive intervention for rising intraocular pressure: development of the Molloy/Bridgeport anesthesia associates observation scale

There is increasing interest in monitoring intraocular pressure (IOP) during surgery in steep Trendelenburg position because of reported incidents of postoperative visual loss (POVL). A review of 17 patients with POVLs showed findings of eyelid edema, chemosis, and ecchymosis. The aim of this study was to link IOP tonometry measurement to an observation scale enabling caregivers to determine when to institute preventive measures to optimize ocular perfusion. The study design was a prospective repeated-measures correlation regression model. Visual assessment of presence of eyelid edema or chemosis and baseline IOP values determined the probability of when an IOP greater than 40 mm Hg (critical threshold) was reached. Both IOP and Molloy/Bridgeport Anesthesia Associates Observation Scale measures were recorded at start of surgery, 30-minute intervals, and end of surgery. Associations between IOP and facial observations were analyzed via multiple logistic regression. Significant predictors of IOP greater than 40 mm Hg were determined to be presence of chemosis and baseline IOP and significantly correlated to increasing IOP. The receiver operating characteristic curve-area under the curve score was 0.86 (standard error +/- 0.03). Caregivers can use this observation scale to assess the need and timing for IOP-normalizing interventions and possibly to prevent POVL.

Testing rocuronium-induced neuromuscular blockade at the stapedius muscle using stapedius reflex measurements

BACKGROUND

Neuromuscular monitoring prior to emergence from anaesthesia has been shown to be necessary to achieve adequate airway protection in order to decrease postoperative pulmonary complications. In the present study we hypothesized that stapedius reflex measurement allows the detection of residual neuromuscular blockade using the stapedius muscle following the administration of rocuronium.

PATIENTS AND METHODS

Parallel stapedius and acceleromyographic measurements were performed on 20 patients undergoing cholecystectomy. Acceleromyographic measurements were continuously performed during the course of anaesthesia, whereas the stapedius reflex was measured on different occasions: (1) after premedication but before anaesthesia induction, (2) after induction, but before administration of muscle relaxant, (3) after administration of muscle relaxant, (4) during the course of surgical anaesthesia at regular intervals, and (5) continuously performed during emergence from anaesthesia, until the stapedius reflex threshold returned to normal.

RESULTS

The intensity of the sound energy at which the stapedius reflex is detectable was similar: 89.5 ± 9.9 dB(mean ± SD) after premedication and after anaesthetic induction. However, after administration of rocuronium, when the twitch height decreased to 5%, the stapedius reflex disappeared, indicating a total block of the stapedius muscle.During the recovery phase (twitch>10%) significantly higher sound energies compared to baseline values were necessary to evoke the reflex, indicating residual inhibition of the stapedius muscle. At the point where stapedius reflex threshold returned to normal the twitch height averaged about 50% showing low sensitivity of the tympanometry in detecting residual neuromuscular blockade.

CONCLUSIONS

The neuromuscular effect of rocuronium on the stapedius muscle can be detected using stapedius reflex measurements. Due to its methodological limitation and low sensitivity, the method cannot be recommended for the monitoring of residual neuromuscular blockade.

Monitoring techniques for prevention of procedure-related ischemic damage in aneurysm surgery

OBJECTIVE

To describe the application of intraoperative monitoring techniques during aneurysm surgery and to discuss the advantages and limitations of these techniques in prevention of postoperative neurologic deficits.

METHODS

Articles found in the literature through PubMed for the time frame 1980-2011 and the authors' personal files were reviewed.

RESULTS

Various techniques for detection of vascular insufficiency are available, including direct methods to measure cerebral blood flow and indirect methods to evaluate the integrity of neurologic pathways.

CONCLUSIONS

The choice of monitoring modality should be governed by the vessel and by the vascular territory most at risk during the planned procedure with proper awareness of the potential limits related to each technique. Aneurysm surgery monitoring should help to address issues of continuity and provide a morphologic and functional assessment. Although the use of monitoring devices is still not routine in aneurysm surgery and no standards have been established, combining different monitoring techniques is crucial to optimize aneurysm surgery and avoid or minimize complications.

Estimation accuracy of surgically induced astigmatism on the cornea when neglecting the posterior corneal surface measurement

PURPOSE

To evaluate the accuracy of corneal surgically induced astigmatism (SIA) estimation when neglecting the posterior corneal surface measurement.

METHODS

Fifty right eyes undergoing phacoemulsification were measured with a rotating Scheimpflug camera (Pentacam; Oculus Inc., Wetzlar, Germany) both before and after surgery. Clear corneal incisions with one suture were used in the phacoemulsification surgery. The keratometric corneal SIA (KSIA) was derived using the anterior corneal surface measurement and the keratometric index (1.3375) while neglecting the posterior corneal surface measurement. The Pentacam-derived total corneal SIA (PSIA) was derived by vergence tracing and polar value analysis [KP(135) and KP(180)] of the measurements on both corneal surfaces.

RESULTS

The mean arithmetic estimation errors of the KSIA for the PSIA were 0.16 ± 0.32 (-0.52 to 1.14) D for the KP(135), and -0.02 ± 0.30 (-0.75 to 1.29) D for the KP(180). There was a significant difference between the KP(135) components of the KSIA and PSIA. Bivariate analysis revealed a statistically significant difference between the combined means of the KSIA and PSIA. Overall, 24% had either a KP(135) component of the KSIA that differed by > 0.50 D from that of the PSIA or a KP(180) component of the KSIA that differed by > 0.50 D from that of the PSIA. The blurring strength caused by neglecting the posterior corneal measurement was > 0.50 D in 24% of eyes.

CONCLUSION

Neglecting the posterior corneal surface measurement may lead to significant deviation in the corneal SIA estimation after phacoemulsification in a proportion of eyes.

Goal-directed therapy in anesthesia: any clinical impact or just a fashion?

Goal-directed therapy (GDT) describes the protocolized use of cardiac output and related parameters as end-points for fluid and/or inotropic therapy administration. Identifying the patient who will benefit from it has implications throughout perioperative management. The fundamental principle behind GDT is optimizing tissue perfusion by manipulating heart rate, stroke volume, hemoglobin and arterial oxygen saturation to improve oxygen delivery by using fluids, inotropes, red blood cells and supplementary oxygen. Although cardiac output and SvO2 were previously measured using the pulmonary artery catheter, a number of less invasive methods are now available. For intraoperative GDT, the esophageal Doppler-derived Flow Time correct (FTc) is the parameter used most frequently, although other parameters such as stroke volume obtained from Vigileo, PICCO and/or LiDCO, mixed and/or central venous oxygen saturation (SvO2/ScvO2), oxygen delivery and global end diastolic volume (PiCCO system) may be applied in daily clinical practice. The correct target to be followed during the intraoperative period must be clearly established. Most parameters depend primarily on O2 consumption and are not reliable or useful during anesthesia. To date, the quantity and the type of fluids to administer during major elective surgery remain an object of continuing debate. In conclusion, in terms of evidence-based medicine, GDT during anesthesia has a clinical impact when performed using an FTc-based fluids algorithm protocol. In contrast, GDT can be considered unreliable if confusing targets such as SvO2 or ScvO2 higher than 70% during anesthesia are followed.

Safe and sound: pediatric procedural sedation and analgesia

Providing procedural sedation for pediatric patients presents unique challenges. Children's hospitals have protocols in place to provide safe, high-quality sedation care delivered by specialists in pediatric sedation and anesthesiology. However, the demand for procedural sedation for diagnostic and therapeutic procedures is increasing. This article describes some of the key components involved in establishing a protocol for safe and effective pediatric sedation services including screening techniques for patients at higher risk for complications and appropriate monitoring and rescue plans. We also review medications commonly used for pediatric sedation and pain management and discuss resources available to physicians who provide pediatric sedation.

[Standards of multimodal monitoring in obstetrical clinic]

Safety issues of anaesthesia care in obstetrics are extremely important, because they influence the possibility of reducing the complications in mothers, foetus and newborns. Monitoring of haemodynamics is a necessary part of anaesthesia care. A correct estimation of haemodynamics in pregnant with gestosis is possible only when analyzing the rates of peripheral resistance and a cardiac index. 72 pregnant patients with gestosis were examined, 48 of above had a moderate form. In latter group, a hypokinetic type of haemodynamics was revealed in 4% of patients, normokinetic type in 86% and a hyperkinetic type in 10%. In 24 patients with severe gestosis the distribution was as 82%, 18% and 0% respectively. Measuring the central haemodynamic parameters with a bio-impedance spectrometry allows to choose the hypotensive therapy in a more accurate way to ensure the control of its effectiveness, and to consider the need in early delivery in proper time when in aggravation of gestosis, providing better outcomes for women and children.

Intraoperative echocardiography in valvular heart disease: an evidence-based appraisal

Intraoperative (IO) transesophageal echocardiography (TEE) is widely used for assessing the results of valvular heart disease (VHD) surgery. Epiaortic ultrasonography (EAU) has been recommended for prevention of perioperative strokes. To what extent does high-quality evidence justify the widespread use of these imaging modalities? In March 2009, we searched MEDLINE (PubMed and OVID interfaces) and EMBASE for studies published in English using database-specific controlled vocabulary describing the concepts of IOTEE, cardiac surgery, VHD, and EAU. We found no randomized trials or studies with control groups assessing the impact of IOTEE in VHD surgery. Pooled analysis of 8 observational studies including 15,540 patients showed an average incidence of 11% for prebypass surgical changes and 4% for second pump runs, suggesting that patients undergoing VHD surgery may benefit significantly from IOTEE, particularly from postcardiopulmonary bypass IOTEE in aortic repair and mitral repair and replacement, but less so in isolated aortic replacement. Further available indirect evidence was satisfactory in the test accuracy and surgical quality control aspects, with low complication rates for IOTEE. The data supporting EAU included 12,687 patients in 2 prospective randomized studies and 4 nonrandomized, controlled studies, producing inconsistent outcome-related results. Despite low-quality scientific evidence supporting IOTEE in VHD surgery, we conclude that indirect evidence supporting its use is satisfactory and suggests that IOTEE may offer considerable benefit in valvular repairs and mitral replacements. The value of IOTEE in isolated aortic valve replacement remains less clear. Evidence supporting EAU is scientifically more robust but conflicting. These findings have important clinical policy and research implications.

[Thromboelastography/-metry and external quality control. Results of a pilot study]

Thromboelastography/thromboelastometry (TEG/ROTEM) is widely used in near-patient setting, especially in perioperative and intensive care medicine for the management of acute bleeding. Until now a comprehensive quality management especially an external quality control of TEG/ROTEM results is not established. Here we report about our results of a pilot survey performed in 2008 and 2009 integrated in the External Quality Assessment Schemes (EQAS) performed by INSTAND. According to this first EQAS data ROTEM results can be controlled in external quality schemes using lyophilized plasma samples. The clot firmness (A20) and clot formation kinetics characterized by the alpha-angle showed very good reproducibility both between the participants and between different surveys. Variations for CT and CFT were considerably higher especially in the plasma sample with reduced fibrinogen level. Regular participation in an external quality assurance will help to confirm this beneficial technology in emergency settings.

[General surgical procedures in patients with electrical pacemaker]

Work of the implanted electric pacemaker (EP) was assessed in 99 patients, aged 62.4±9.6 years, during non-cardiological surgery. Inhibition of the EP stimuli was registered in 9 (9.1%) patients, short episodes of uneffective stimulation with synchronization disturbation--in 2 (2%) patients and change of stimulation regimen was registered in the same number of patients by electocoagulation. Episodes of myopotential inhibition not assotiated with electrocoagulation was registered in 4 cases. The ascertained rhythm disturbances require a thorough preoperative check-up, intraoperative ECG control and short use of monopolar electrocoagulation.

[Comparison of transthoracic, transesophageal, and intracardiac echocardiography sensitivity for guiding transseptal puncture during radiofrequency ablation in the left atrium]

The paper contains comparison of sensitivity and rates of false negative results of transthoracic (TT), transesophageal (TE), and intracardiac (IC) echocardiography (echoCG) during transseptal puncture in the run of the procedure of radiofrequency ablation of atrial fibrillation. In the work fulfilled we analyzed results of 208 echocardiographical intraprocedural investigations conducted with the aim of visualization of interatrial septum (IAS) during transseptal puncture. TT, TE and IC echoCG were carried out in 32, 26, and 150 cases, respectively. Phenomenon of IAS stretching was visualized by TT echoCG in 2 (6%) cases (sensitivity 6.7%). At TE tenting phenomenon was verified in 20 patients (20%) (sensitivity 86.9%). Puncture of IAS was carried out under IC echoCG control in 127 patients. Puncture was made in the center of thin portion of IAS (in the region of fossa ovalis), in its upper and lower portions in 65, 28, and 15.7% of cases, respectively. Sensitivity of IC echoCG was 98.4%. Rate of false positive results reached 92.8, 13.04 and 1.5% for TT, TE and IC echoCG, respectively. At present IC echoCG is most sensitive and safe ultrasound technique for verification of optimal positioning of the system for conduct of transseptal puncture in the region of IAS in comparison with TT and TE echoCG.

Guideline for monitoring and management of pediatric patients during and after sedation for diagnostic and therapeutic procedures

The safe sedation of children for procedures requires a systematic approach that includes the following: no administration of sedating medication without the safety net of medical supervision, careful presedation evaluation for underlying medical or surgical conditions that would place the child at increased risk from sedating medications, appropriate fasting for elective procedures and a balance between depth of sedation and risk for those who are unable to fast because of the urgent nature of the procedure, a focused airway examination for large tonsils or anatomic airway abnormalities that might increase the potential for airway obstruction, a clear understanding of the pharmacokinetic and pharmacodynamic effects of the medications used for sedation as well as an appreciation for drug interactions, appropriate training and skills in airway management to allow rescue of the patient, age- and size-appropriate equipment for airway management and venous access, appropriate medications and reversal agents, sufficient numbers of people to both carry out the procedure and monitor the patient, appropriate physiologic monitoring during and after the procedure, a properly equipped and staffed recovery area, recovery to presedation level of consciousness before discharge from medical supervision, and appropriate discharge instructions.

Comparison of contemporary EEG derived depth of anesthesia monitors with a 5 step validation process

During the last decennium, a growing number of depth of anesthesia monitors, extracting information from the spontaneous electroencephalogram (EEG) have been developed and commercialized. The growing interest in depth of anesthesia monitoring resulted in an intensified technological progress. Innovations on both hardware and mathematical algorithms were introduced for improving the extraction of data. Because of the abundance of monitors now commercially available, it becomes increasingly important to develop a standardized reproducible methodology for comparing depth of anesthesia monitors. In this review, the authors present a strategy to compare monitors of the hypnotic component of anesthesia, based on the available literature and their own experience with validation studies. They also discuss the level of validation of the most commonly used EEG derived depth of anesthesia monitors.