[Serious intraoperative problems--a five-year review of 83,844 anesthetics]

All India Difficult Airway Association guidelines in practice-A survey

Background and Aims:

The All India Difficult Airway Association (AIDAA) has come up with difficult airway (DA) guidelines to suit the Indian context. We conducted an online survey with the primary aim to find out the awareness about AIDAA guidelines and adherence to them in clinical practice. The secondary aims were to explore variations in practice with respect to experience or the type of the institute.

Methods:

An online web-based questionnaire survey was sent to all practising anaesthesiologists who attended an airway workshop. The validated and piloted questionnaire consisted of 23 questions and the practice patterns were asked to be graded on a Likert scale of four.

Results:

The response rate was 66%. Awareness about AIDAA guidelines was high (81%) but adherence varied. Apnoeic nasal oxygen insufflation was always practised by only 19.59%.Only 79.7%of the respondents always used capnography to confirm intubation. While 23.64% did not ensure a safe peripheral oxygen saturation (SpO₂) level of 95% to do repeat laryngoscopy, 64% chose supraglottic devices after three failed laryngoscopic attempts. A departmental debriefing of a DA event and issuing an alert card to the patient was practised by 58.78% and 52.7%, respectively. Although 50% had training to do cricothyrotomy, only 41% had ready access to a cricothyrotomy set in their workplace. The use of capnography was more prevalent in private institutions. The survey revealed a safety gap with some recommendations like debriefing of a DA event, alert card, nasal oxygenation etc.

Conclusion

Awareness about AIDAA guidelines is high among our practising anaesthesiologists, but adherence to the recommendations varied and there is room for improvement, especially for debriefing a DA event, issuing an alert card, the use of capnography and nasal oxygenation.

D-Amphetamine Rapidly Reverses Dexmedetomidine-Induced Unconsciousness in Rats

D-amphetamine induces emergence from sevoflurane and propofol anesthesia in rats. Dexmedetomidine is an α₂-adrenoreceptor agonist that is commonly used for procedural sedation, whereas ketamine is an anesthetic that acts primarily by inhibiting NMDA-type glutamate receptors. These drugs have different molecular mechanisms of action from propofol and volatile anesthetics that enhance inhibitory neurotransmission mediated by GABA_A receptors. In this study, we tested the hypothesis that d-amphetamine accelerates recovery of consciousness after dexmedetomidine and ketamine. Sixteen rats (Eight males, eight females) were used in a randomized, blinded, crossover experimental design and all drugs were administered intravenously. Six additional rats with pre-implanted electrodes in the prefrontal cortex (PFC) were used to analyze changes in neurophysiology. After dexmedetomidine, d-amphetamine dramatically decreased mean time to emergence compared to saline (saline:112.8 ± 37.2 min; d-amphetamine:1.8 ± 0.6 min, p < 0.0001). This arousal effect was abolished by pre-administration of the D₁/D₅ dopamine receptor antagonist, SCH-23390. After ketamine, d-amphetamine did not significantly accelerate time to emergence compared to saline (saline:19.7 ± 18.0 min; d-amphetamine:20.3 ± 16.5 min, p = 1.00). Prefrontal cortex local field potential recordings revealed that d-amphetamine broadly decreased spectral power at frequencies <25 Hz and restored an awake-like pattern after dexmedetomidine. However, d-amphetamine did not produce significant spectral changes after ketamine. The duration of unconsciousness was significantly longer in females for both dexmedetomidine and ketamine. In conclusion, d-amphetamine rapidly restores consciousness following dexmedetomidine, but not ketamine. Dexmedetomidine reversal by d-amphetamine is inhibited by SCH-23390, suggesting that the arousal effect is mediated by D₁ and/or D₅ receptors. These findings suggest that d-amphetamine may be clinically useful as a reversal agent for dexmedetomidine.

Perioperative anaphylaxis and investigations: a local study in Hong Kong

INTRODUCTION

Data on local intraoperative anaphylaxis in Hong Kong is scarce, with few reviews available. We aimed to study the characteristics, presentations and workup results of cases referred to a local allergy clinic.

METHODS

A retrospective review was performed of patient referrals and workup results for suspected intraoperative anaphylaxis at Queen Mary Hospital drug allergy clinic in 2012-2016.

RESULTS

Tryptase was checked in only 81.7% (49/60) of the cases, most of which showed elevation (71.4%, 35/49). Among the 59 patients who received a workup, 47 (79.7%) showed positive findings, with a particularly high yield in the tryptase-positive subgroup (88.6%, 31/35). Among the 54 patients who consented to skin tests (the most sensitive investigation), 43 (79.6%) cases were positive. Overall, neuromuscular blockers were the commonest cause (25.0%, 15/60) of intraoperative anaphylaxis, while antibiotics ranked second (23.3%, 14/60). The timing of reactions was an important indication of potential allergens. For example, the majority of the neuromuscular blocker allergies occurred during the induction phase, while all gelofusine allergic events were in the maintenance phase of anaesthesia. 13 (21.7%) out of 60 cases received subsequent general anaesthesia procedures, with no recurrence of allergic reactions.

CONCLUSION

Proper workup after an intraoperative anaphylactic event has a fairly good chance of identifying the causative allergen. These results are useful for patient management and the planning of subsequent anaesthetic procedures.

Sex effects on behavioral markers of emergence from propofol and isoflurane anesthesia in rats

Clinical studies have demonstrated sex-related differences in recovery from surgical anesthesia. This study aimed to characterize the emergence pattern following two anesthesia regimens in both sexes of rats. We considered six different markers of emergence from anesthesia: sigh, eye blinking, forelimb movement, mastication, neck extension, and recovery of the righting reflex (RORR). Spontaneous motor activity 24 h after the anesthesia induction was also examined. Our results showed that the rank order of the emergence latency after intraperitoneal propofol, PRO, exposure was forelimb movement < sigh < blink < mastication < neck extension < RORR, while after inhaled isoflurane, ISO, anesthesia the sequence was changed as sigh < blink < mastication < forelimb movement < neck extension < RORR in both male and female rats. Moreover, the latency to emergence after PRO in female rats was significantly higher than male rats, although following ISO there was no difference between the sexes (P < 0.001; P > 0.05, respectively). Open-field testing revealed no difference in PRO and ISO spontaneous locomotor activity due to drug administration (P > 0.05). These two anesthetics presented different emergence sequences. Although clinical data suggests that females arouse faster than males from anesthesia with propofol, our intraperitoneal technique in a rodent model had the opposite effect. Pharmacokinetic analysis demonstrated increased absorption of injected propofol for the female rats in our study, emphasizing the role of sexual dimorphism in drug distribution in rodents. Despite these pharmacokinetic differences, the pharmacodynamic effects of the drugs were remarkably consistent among both sexes through emergence.

Peri-Operative Anaphylaxis-An Investigational Challenge

Patients with suspected peri-operative anaphylaxis (POP) require thorough investigation to identify underlying trigger(s) and enable safe anesthesia for subsequent surgery. The changing epidemiology of POP has been striking. Previous estimates of the incidence of POP have ranged between 1:6,000 and1:20,000 anesthetics, but more recent data from France and the United Kingdom suggest an estimated incidence of 1:10,000. Other important changes include a change in the hierarchy of well-recognized triggers, with antibiotics (beta-lactams) supplanting neuromuscular blockers (NMB) as the leading cause of POP. The emergence of chlorhexidine, patent blue dye, and teicoplanin as important triggers have also been noteworthy findings. The mainstay of investigation revolves around critical analysis of the time-line of events leading up to anaphylaxis coupled with judicious skin testing. Skin tests have limitations with respect to unknown predictive values for most drugs/agents and therefore, knowledge of background positivity in healthy controls, test characteristics of individual drugs and the use of non-irritant concentrations is essential to avoid both false-positive and false-negative results. Specific IgE assays for individual drugs are available only for a limited number of agents and are not a substitute for skin testing. Acute serum total tryptase has a high specificity and positive predictive value in IgE-mediated POP anaphylaxis but is limited by its moderate sensitivity and negative predictive value. Planning for safe anesthesia in this group of patients is particularly challenging and consequently anesthetists need to be alert to the possibility of repeat episodes of anaphylaxis. Because of the limitations of current investigations for POP, collecting systematic data on the outcome of repeat anesthesia is valuable in validating current investigatory approaches. This paper reviews the changing epidemiology of POP with reference to the main triggers, and the investigation and outcome of subsequent anesthesia.

An Unexpected Cause of an Acute Hypersensitivity Reaction during Recovery from Anaesthesia

Acute hypersensitivity reactions to chlorhexidine in the operating room are probably more likely to occur during the early phases of anaesthesia because chlorhexidine is often used for cleaning the surgical field or during placement of indwelling catheters. We report a case of an acute hypersensitivity reaction that occurred in the post anaesthetic care unit. Subsequent skin testing suggested sensitivity to chlorhexidine, which had been applied over the vaginal mucosa at the end of surgery. Relevant issues in the investigation of acute hypersensitivity reactions in the post anaesthetic period are discussed.

Intradermal skin tests for rocuronium and cisatracurium in patients with a history of allergy: a retrospective study

BACKGROUND

Neuromuscular blocking agents (NMBAs) are a leading cause of perioperative anaphylaxis. However, the performance of systematic screening skin tests to detect reactions for NMBAs prior to general anesthesia is not recommended. We retrospectively examined intradermal tests (IDTs) for rocuronium and cisatracurium in patients with a history of allergy.

METHODS

We reviewed the records of patients who underwent IDTs for NMBAs between January 1 and December 31, 2016. We analyzed the patients' allergy histories and skin test results for NMBAs.

RESULTS

The overall prevalence of positive IDTs was 5.8% (26/451), and there was no significant difference in prevalence among allergy types (P = 0.655). In logistic regression analysis, there was no allergy history that had a significant effect on positive IDT for NMBAs.

CONCLUSIONS

We found no association between allergy history and positive skin test for NMBAs. Therefore, a systematic screening test for NMBAs or other anesthetic agents before anesthesia is not considered necessary even in patients with an allergy history.

Incidence of hypersensitivity and anaphylaxis with sugammadex

STUDY OBJECTIVE

To evaluate the incidence of hypersensitivity and anaphylaxis after administration of sugammadex.

DESIGN

Retrospective analysis.

SETTING

Sugammadex clinical development program and post-marketing experience.

PATIENTS

Surgical patients and healthy volunteers who received sugammadex or placebo/comparator with anesthesia and/or neuromuscular blockade (NMB).

INTERVENTIONS

Sugammadex administered as 2.0 mg/kg at reappearance of the second twitch, 4.0 mg/kg at 1-2 post-tetanic count, or 16.0 mg/kg at 3 min after rocuronium 1.2 mg/kg.

MEASUREMENTS

Three analytical methods were used: 1) automated MedDRA queries; 2) searches of adverse events (AEs) consistent with treatment-related hypersensitivity reactions as diagnosed by the investigator; and 3) a retrospective adjudication of AEs suggestive of hypersensitivity by a blinded, independent adjudication committee (AC). In addition, a search of all post-marketing reports of events of hypersensitivity was performed, and events were retrospectively adjudicated by an independent AC. Anaphylaxis was determined according to Sampson Criterion 1.

MAIN RESULTS

The pooled dataset included 3519 unique subjects who received sugammadex and 544 who received placebo. The automated MedDRA query method showed no apparent increase in hypersensitivity or anaphylaxis with sugammadex as compared to placebo or neostigmine. Similarly, there was a low overall incidence of AEs of treatment-related hypersensitivity (<1%), with no differences between sugammadex and placebo or neostigmine. Finally, the retrospective adjudication of AEs suggestive of hypersensitivity showed a low incidence of hypersensitivity (0.56% and 0.21% for sugammadex 2 mg/kg and 4 mg/kg, respectively), with an incidence similar to subjects who received placebo (0.55%). There were no confirmed cases of anaphylaxis in the pooled studies. During post-marketing use, spontaneous reports of anaphylaxis occurred with approximately 0.01% of sugammadex doses.

CONCLUSIONS

Subjects who received sugammadex with general anesthesia and/or NMB had a low overall incidence of hypersensitivity, with no apparent increase in hypersensitivity or anaphylaxis with sugammadex as compared to placebo or neostigmine.

[Anesthesia problem cards-indispensable yet problematic : Nationwide survey on experiences from clinical practice]

BACKGROUND

Anesthetic procedures may lead to severe and potentially life-threatening complications (e. g. difficult airway, allergic reactions, malignant hyperthermia). Most complications can be avoided in future anesthetic procedures with adequate preparation (e. g. awake intubation, trigger-free anesthesia). In Germany, anesthesia problem cards were introduced two decades ago to identify patients at risk and to increase patient safety by creating a standardized documentation system for anesthesia-related complications. The purpose of our study was to evaluate the utility and problems of anesthesia problem cards in clinical practice.

MATERIAL AND METHODS

All registered members of the German Society of Anesthesiology and Intensive Care Medicine (DGAI) and the Professional Association of German Anesthesiologists (BDA) (n = 19,042) were invited to participate in an online survey on patient safety. A subsection of the survey focused specifically on anesthesia problem cards and their utility in clinical practice (e. g. field of application, issuing procedures, benefits and problems).

RESULTS

The survey subsection on anesthesia problem cards was completed by 1783 participants. Most agreed that anesthesia problem cards are a useful tool to increase patient safety (n = 1502; 84.2%) and that they are routinely issued after the occurrence of anesthesia-related complications (n = 1664, 93.4%). One of the major problems noted was that patients frequently forget to bring their anesthesia problem cards when presenting for the preanesthetic assessment. This was observed by 1457 participants (81.7%). Furthermore, the information provided on anesthesia problem cards may be inadequately phrased (n = 874; 49.0%) or illegible (n = 833; 46.7%). In addition, the space for individual comments or problem solutions is insufficient (n = 811; 45.5%). Replacements for lost anesthesia problem cards with identical informational content can be issued in only 41.9% (n = 747) of the participants' departments.

CONCLUSION

Anesthesia problem cards are considered a useful tool to increase patient safety and are frequently issued in clinical practice; however, in the document's current form its full potential for risk minimization cannot be exploited. Structural changes are required to increase documentation quality and reproducibility. Concerning its informational content, the spectrum of included complications and their individual solutions need to be expanded to meet the requirements of modern anesthetic practice.

Analysis of Clinical Indicators of Quality in Patients with Endotracheal intubation

INTRODUCTION

Quality and safety in anaesthesia is usually monitored by analysis of perioperative mortality-morbidity and are influenced by anaesthetic and non-anaesthetic factors.

AIM

This study was conducted to analyse the incidence of clinical indicators of quality in endotracheally intubated patients undergoing general abdominal surgeries and obstetric and gynaecological procedures under general anaesthesia and to determine contributing factors for the same.

MATERIALS AND METHODS

This retrospective study was conducted at our institute over a period of 12 months and 709 case records of patients were reviewed. Patients aged 14 years and more belonging to all ASA groups undergoing abdominal surgeries for general and obstetric and gynaecological causes under General Anaesthesia (GA) with endotracheal intubation posted for both elective and emergency surgeries were included in the study. Demographic details including name, age, sex, hospital number, height, weight, body mass index, type of surgery, nature of surgery, duration, American Society of Anaesthesiologists (ASA) physical status were recorded and presence or absence of clinical indicators of quality (presence of cannot intubate cannot ventilate scenario, occurrence of dental injury, episode of non cardiogenic pulmonary oedema, incidents of residual neuromuscular blockade, existence of aspiration pneumonia, unplanned ICU/HDU admissions, interventions for respiratory/ cardiac arrest, occasions of respiratory distress in the recovery period, occurrence of respiratory arrest within 48 hours and re-intubation) were noted and analysed for all 709 patients.

RESULTS

Total 709 patients were analysed in our study. We found that incidence of ICU admission was 1.83% and that of respiratory distress which needed intervention were 0.56%. A total of 0.28% patients needed reintubation. Residual neuromuscular blockade was seen in 0.28% patients. We did not find any case of respiratory and cardiac arrest and also there was no Cannot Ventilate and Cannot Intubate (CVCI) situation encountered in our study. SPSS for windows (version 17.0) was used as statistical software. Chi-square test was the statistical test for significance. A p-value < 0.05 was considered significant.

CONCLUSION

Proper optimization of patients prior to surgery and optimal perioperative care will result in better quality of care and safety in anaesthesia. Documentation of events and its management during perioperative period will help to know the fields of inappropriate management and thereby improve the quality of care and detect the incidence rates with accuracy and help to formulate protocol for institution.

Benzodiazepine Allergy With Anesthesia Administration: A Review of Current Literature

The incidence of anaphylactic/anaphylactoid reactions has been reported to vary between 1 : 3500 and 1 : 20,000 cases with a mortality rate ranging from 3 to 9%. Clinical signs present as skin rash, urticaria, angioedema, bronchospasm, tachycardia, bradycardia, and hypotension. Rapid identification and treatment are crucial to overall patient prognosis, as delayed intervention is associated with increased mortality. Diagnosis may be confirmed with clinical presentation, serum tryptase levels, and skin test results. While the main causative agents in anesthetic practice are typically neuromuscular blocking agents (NMBs), latex, and antibiotics, this review aims to discuss recognition, management, and preventive measures in perioperative anaphylactic/anaphylactoid reactions from benzodiazepine administration.

Pediatric anaphylaxis in the operating room for anesthesia residents: a simulation study

BACKGROUND

Pediatric intraoperative emergencies are rare but it is crucial for an anesthesia resident to be proficient in their management. Even the more common emergencies like anaphylaxis may not happen frequently for this proficiency to occur. Simulation increases exposure to these rare events in a safe learning environment to improve skills and build confidence while standardizing curriculum.

OBJECTIVE

Anesthesia residents participated in a simulated case of intraoperative pediatric anaphylaxis to evaluate knowledge and performance gaps. The study also sought to determine whether a difference exists between second- (CA2) and third-year (CA3) anesthesia residents when managing pediatric anaphylaxis and cardiopulmonary arrest.

METHODS

Anesthesia residents completed a standardized programmed simulation of intraoperative anaphylaxis in a 5-year old undergoing tonsillectomy and adenoidectomy. Anaphylaxis presented and progressed to bradycardia and pulseless electrical activity if anaphylaxis went unnoticed or untreated. Key time points were recorded. A scripted debriefing and written evaluation followed.

RESULTS

Average time to diagnose anaphylaxis was 7.6 min, and time to give epinephrine was 6.5 min. Thirty-five percent of residents started epinephrine infusion following initial bolus. Average time calling for help between CA3 and CA2 residents was 2.5 min vs 5 min (P = 0.01). CA3 residents verbalized a broader differential, including malignant hyperthermia and pneumothorax. Progression to pulseless electrical activity occurred in 65% of sessions prior to epinephrine being administered. No resident initiated chest compressions for bradycardia.

CONCLUSIONS

Important performance deficits were seen in senior anesthesia residents during a simulated case of pediatric intraoperative anaphylaxis. Although CA3 performed better, deficits still existed. Anesthesia residents and training programs should partner in developing additional training recognizing anaphylaxis, pulseless electrical activity, and indication for chest compressions in a child.

L'incidence de l'hypotension post-intubation endotrachéale chez des patients en salle de réanimation: impact des définitions

Objectif Notre objectif primaire est de mesurer l'incidence d'HPI selon quatre définitions différentes retrouvées dans la littérature. Notre principal objectif secondaire est d'évaluer l'impact de la présence d'instabilité hémodynamique avant l'intubation sur l'incidence d'HPI. Le deuxième objectif secondaire consiste à déterminer l'incidence de l'HPI en fonction de l'intervalle de temps durant lequel la première hypotension survient. Méthode Une cohorte prospective a été constituée par les patients intubés en salle de réanimation à l'hôpital de l'Enfant-Jésus entre le 28/06/2011 et le 12/07/2012. L'HPI était globalement définie comme ≥1 mesure de tension artérielle systolique <90 mmHg suivant l'intubation. Les différentes définitions étudiées faisaient varier le temps de mesure de la tension artérielle (TA) après l'intubation, soit 1) jusqu'à 5 minutes, 2) jusqu'à 15 minutes, 3) jusqu'à 30 minutes et 4) en tout temps lors du séjour en salle de réanimation. Résultat Au cours de la période à l'étude, 155 patients ont été intubés sur place dont 81 patients qui répondaient aux critères d'inclusion. L'incidence de l'HPI pour chaque définition est respectivement de 9.9%, 18.5%, 24.7% et 28.4%. La comparaison entre chacune de ces incidences révèle une différence statistiquement significative (p<0.05), à l'exception des deux dernières. L'incidence cumulative d'HPI à tout moment suivant l'intubation chez les patients présentant une hypotension pré-intubation est de 62.5% (IC 95% 28.5-87.5) en opposition aux patients hémodynamiquement stables en pré-intubation qui présentaient une incidence d'HPI de 24.7% (IC 95% 16.1-35.8).

CONCLUSION

L'hypotension post-intubation est un effet indésirable fréquent chez les patients au département d'urgence et son incidence varie de façon significative en fonction de la définition temporelle utilisée au sein d'une même cohorte de patients.

The German Critical Incident Reporting System for Anesthesiology: CIRSains

BACKGROUND

In June 2010, the Helsinki Declaration was passed. As a result, an online nationwide critical incident reporting system named CIRSmedical Anaesthesiology (CIRSains) was implemented in Germany. The aim of the article is to evaluate CIRSains for practicability and to provide solutions to the problems detected during evaluation.

METHODS

Every medical staff member could take part voluntarily. Data were deidentified. All reports for anesthesiology (1548) were taken into account. Data collection lasted from April 2010 to February 2011. Incident report forms were classified according to World Health Organization and National Patient Safety Agency taxonomy.

RESULTS

Most reports (1347; 87.0%) contained American Society of Anaesthesiologists (ASA) classification, stratifying the severity of patients' underlying disease. Only some mentioned patients' age, even less sex. Physicians filed more reports than nurses. Staff-related factors constituted 794 (51.3%) choices, with attention issues (433; 28.0%) and routine violations (143; 9.2%) leading. Clinical processes (443; 28.6%), medication (347; 22.4%), and medical devices (530; 34.2%) were the leading incident category types. Most consequences ranged in low (398; 25.7%) and moderate (826; 53.4%) risk categories. Mitigating factors were barely mentioned.

CONCLUSION

CIRSains displays the German effort to establish the Helsinki declaration. Easy accessibility, anonymity, medicolegal safety, and high flexibility resulted in high usage. The study shows a sufficient practicability of the database, but the data input has to be improved for better scientific use, for example, by implementation of more multiple-choice questions. Given the high magnitude and importance of patient safety problems, improving CIRSains remains a priority for the future.

Suspected Anaphylactic Reaction Prior to Induction of Anesthesia

Although uncommon, anaphylactic reactions during surgery are very dangerous and can result in serious morbidity. Various anesthetics can trigger anaphylactic reactions, and incidents with cephalosporin antibiotics are on the rise. In the case presented, an 84-year-old woman scheduled for calcaneus fracture surgery, was injected with cefbuperazone as a prophylactic antibiotic. On the way to the operating room, before induction of anesthesia, the patient lost consciousness and showed signs of hypoxemia, and anaphylactic reaction, which included hypotension, bronchospasm, and rash. Five hours after immediate intubation and fluid resuscitation, the patient was extubated and transferred to the general ward. Eight weeks later, the skin prick test confirmed a positive reaction to cefbuperazone.

Allergic Reactions to Dental Materials-A Systematic Review

INTRODUCTION

Utility of various dental materials ranging from diagnosis to rehabilitation for the management of oral diseases are not devoid of posing a potential risk of inducing allergic reactions to the patient, technician and dentist. This review aims to develop a systematic approach for the selection and monitoring of dental materials available in the market thereby giving an insight to predict their risk of inducing allergic reactions.

MATERIALS AND METHODS

Our data included 71 relevant articles which included 60 case reports, 8 prospective studies and 3 retrospective studies. The source of these articles was Pub Med search done with the following terms: allergies to impression materials, sodium hypochlorite, Ledermix paste, zinc oxide eugenol, formaldehyde, Latex gloves, Methyl methacrylate, fissure sealant, composites, mercury, Nickel-chromium, Titanium, polishing paste and local anaesthesia. All the relevant articles and their references were analysed. The clinical manifestations of allergy to different dental materials based on different case reports were reviewed.

RESULTS

After reviewing the literature, we found that the dental material reported to cause most adverse reactions in patients is amalgam and the incidence of oral lichenoid reactions adjacent to amalgam restorations occur more often than other dental materials.

CONCLUSION

The most common allergic reactions in dental staff are allergies to latex, acrylates and formaldehyde. While polymethylmethacrylates and latex trigger delayed hypersensitivity reactions, sodium metabisulphite and nickel cause immediate reactions. Over the last few years, due to the rise in number of patients with allergies from different materials, the practicing dentists should have knowledge about documented allergies to known materials and thus avoid such allergic manifestations in the dental clinic.

Incidence of postintubation hemodynamic instability associated with emergent intubations performed outside the operating room: a systematic review

OBJECTIVE

Hemodynamic instability following emergent endotracheal intubation (EETI) is a potentially life-threatening adverse event. The objectives of this systematic literature review were to document the incidence of postintubation hemodynamic instability (PIHI), to determine the definitions for PIHI used in the available literature, and to examine factors associated with PIHI in adult patients who require EETI.

DATA SOURCE

Articles published in Medline (1966-August 2012).

STUDY SELECTION

This systematic review included adult, in-hospital studies of EETIs. Studies with nonemergent or pediatric patient populations were excluded.

DATA EXTRACTION

Two authors independently performed data abstraction. Disagreements were resolved by a third party. The methodological quality of included studies was assessed with the Newcastle-Ottawa Quality Assessment Scale for Cohort Studies.

DATA SYNTHESIS

We estimated the pooled prevalence of PIHI across studies using a random effects meta-analysis. Subgroups analyzed included study design, intubation setting, geographic location of the study, physician experience, medications used for sedation, neuromuscular blockade, and definition of PIHI. Eighteen studies were analyzed, with sample sizes from 84 to 2,833 patients. The incidence of PIHI ranged from 5 to 440 cases per 1,000 intubations, with a pooled estimate of 110 cases per 1,000 intubations (95% CI 65-167).

CONCLUSIONS

PIHI was found to occur in 110 cases per 1,000 in-hospital, emergent intubations. However, heterogeneity among the included studies limits the reliability of this summary estimate. Further investigation is warranted.

Dextroamphetamine (but Not Atomoxetine) Induces Reanimation from General Anesthesia: Implications for the Roles of Dopamine and Norepinephrine in Active Emergence

Methylphenidate induces reanimation (active emergence) from general anesthesia in rodents, and recent evidence suggests that dopaminergic neurotransmission is important in producing this effect. Dextroamphetamine causes the direct release of dopamine and norepinephrine, whereas atomoxetine is a selective reuptake inhibitor for norepinephrine. Like methylphenidate, both drugs are prescribed to treat Attention Deficit Hyperactivity Disorder. In this study, we tested the efficacy of dextroamphetamine and atomoxetine for inducing reanimation from general anesthesia in rats. Emergence from general anesthesia was defined by return of righting. During continuous sevoflurane anesthesia, dextroamphetamine dose-dependently induced behavioral arousal and restored righting, but atomoxetine did not (n = 6 each). When the D1 dopamine receptor antagonist SCH-23390 was administered prior to dextroamphetamine under the same conditions, righting was not restored (n = 6). After a single dose of propofol (8 mg/kg IV), the mean emergence times for rats that received normal saline (vehicle) and dextroamphetamine (1 mg/kg IV) were 641 sec and 404 sec, respectively (n = 8 each). The difference was statistically significant. Although atomoxetine reduced mean emergence time to 566 sec (n = 8), this decrease was not statistically significant. Spectral analysis of electroencephalogram recordings revealed that dextroamphetamine and atomoxetine both induced a shift in peak power from δ (0.1–4 Hz) to θ (4–8 Hz) during continuous sevoflurane general anesthesia, which was not observed when animals were pre-treated with SCH-23390. In summary, dextroamphetamine induces reanimation from general anesthesia in rodents, but atomoxetine does not induce an arousal response under the same experimental conditions. This supports the hypothesis that dopaminergic stimulation during general anesthesia produces a robust behavioral arousal response. In contrast, selective noradrenergic stimulation causes significant neurophysiological changes, but does not promote behavioral arousal during general anesthesia. We hypothesize that dextroamphetamine is more likely than atomoxetine to be clinically useful for restoring consciousness in anesthetized patients, mainly due to its stimulation of dopaminergic neurotransmission.

Suspected intraoperative anaphylaxis to gelatin absorbable hemostatic sponge

Anaphylaxis under anesthesia is a life-threatening medical emergency that requires rapid identification and treatment. Allergies to agents with which the general population are likely to come into contact are usually identified, but patients are exposed to uncommon agents during anesthesia and surgery. Here, we describe a case of anaphylaxis under anesthesia implicating Gelfoam sponges.

Depth of Anesthesia as a Risk Factor for Perioperative Morbidity

Introduction. The prognostic value of age, physical status, and duration of surgery on perioperative course has been extensively studied. However, the impact of deep hypnotic time (time when Bispectral Index values are less than 40) has not been well evaluated. Methods. We designed an observational study to clarify the relative influence of deep hypnotic time (DHT) on outcome. Eligible participants were mentally stable patients over 18 years old scheduled for elective major abdominal surgery. In total, 248 patients enrolled. Data were analyzed using Fisher's exact test and multiple logistic regression. Results. Five variables (DHT, hypotension, age, comorbidity, and duration of surgery) showed statistically significant association with complications, when examined independently. However, when all variables were examined together in a multiple logistic regression model, age and comorbidity were no longer associated with outcome. DHT, hypotension, and duration of surgery were significant predictors of "complications," and "hypotension" was a significant predictor of prolonged hospital stay (P < 0.001).  Conclusion. Deep hypnotic time emerged as a new factor associated with outcome, and its impact compared to other factors such as age, surgery duration, hypotension, and comorbidity is redefined. Monitoring and managing depth of anesthesia during surgery are important and should be part of careful operation planning.

Anaphylaxis during the perioperative period

The incidence of anaphylaxis during anesthesia has been reported to range from 1 in 4000 to 1 in 25,000. Anaphylaxis during anesthesia can present as cardiovascular collapse, airway obstruction, and/or skin manifestation. It can be difficult to differentiate between immune and nonimmune mast cell-mediated reactions and pharmacologic effects from the variety of medications administered during general anesthesia. In addition, cutaneous manifestations of anaphylaxis are less likely to be apparent when anaphylaxis occurs in this setting. The evaluation of IgE-mediated reactions to medications used during anesthesia can include skin testing to a variety of anesthetic agents. Specifically, thiopental allergy has been documented by skin tests. Neuromuscular blocking agents such as succinylcholine can cause nonimmunologic histamine release, but there have also been reports of IgE-mediated reactions in some patients. Reactions to opioid analgesics are usually caused by direct mast cell mediator release rather than IgE-dependent mechanisms. Antibiotics that are administered perioperatively can cause immunologic or nonimmunologic reactions. Protamine can cause severe systemic reactions through IgE-mediated or nonimmunologic mechanisms. Blood transfusions can elicit a variety of systemic reactions, some of which might be IgE-mediated or mediated through other immunologic mechanisms. The management of anaphylactic reactions that occur during general anesthesia is similar to the management of anaphylaxis in other situations.

Incidence of Intraoperative Hypersensitivity Reactions: A Registry Analysis

Background:

Previously reported incidences for intraoperative hypersensitivity reactions vary more than 15-fold. The goal was to determine the incidence of intraoperative hypersensitivity events at a U.S. surgical center.

Methods:

With institutional review board (Cleveland, Ohio) approval and waiver of written/informed consent, the anesthesia records of adult patients undergoing noncardiac surgery from 2005 to 2011 at the Cleveland Clinic were queried using a novel electronic search protocol developed to identify potential hypersensitivity reactions: cardiovascular collapse defined as systolic arterial blood pressure less than 50 mmHg; administration of epinephrine; administration of diphenhydramine; physician comments in the anesthesia record suggestive of hypersensitivity reactions; laboratory tests for histamine, tryptase, or immunoglobulin-E within 24 h of surgery; and International Classification of Diseases, Ninth Revision, codes suggestive of hypersensitivity reactions. Each electronically identified candidate chart was evaluated by an adjudication committee. Hypersensitivity reactions were graded on a 5-point severity scale. From these data, the authors determined the proportion of operations having adjudicated hypersensitivity reactions, and calculated the 95% exact binomial CI.

Results:

Among 178,746 records, 4,008 charts were identified by the search strategies. After adjudication, 264 hypersensitivity cases were identified. The overall incidence of hypersensitivity reactions was 1:677 surgeries, corresponding to 15 (95% CI, 13 to 17) cases per 10,000 operations. The incidence of severe hypersensitivity reactions (grades 3 to 5) was 1:4,583, corresponding to 2 (95% CI, 2 to 3) cases per 10,000 operations.

Conclusions:

The incidence of severe hypersensitivity reactions was similar to previous reports. However, the overall incidence of hypersensitivity reactions was much greater than reported elsewhere, possibly because of a comprehensive search strategy.

Perceived barriers to computerised quality documentation during anaesthesia: a survey of anaesthesia staff

BACKGROUND

Underreporting of intraoperative events in anaesthesia is well-known and compromises quality documentation. The reasons for such omissions remain unclear. We conducted a questionnaire-based survey of anaesthesia staff to explore perceived barriers to reliable documentation during anaesthesia.

METHODS

Participants anonymously completed a paper-based questionnaire. Predefined answers referred to potential barriers. Additional written comments were encouraged. Differences between physician and nurse anaesthetists were tested with t-tests and chi-square tests.

RESULTS

Twenty-five physician and 30 nurse anaesthetists (81% of total staff) completed the survey. The reported problems referred to three main categories: (I) potential influences related to working conditions and practices of data collection, such as premature entry of the data (indicated by 85% of the respondents), competing duties (87%), and interfering interruptions or noise (67%); (II) problems referring to institutional management of the data, for example lacking feedback on the results (95%) and lacking knowledge about what the data are used for (75%); (III) problems related to specific attitudes, e.g., considering these data not useful for quality improvement (47%). Physicians were more sceptical than nurses regarding the relevance of these data for quality and patient safety.

CONCLUSIONS

The common perceived difficulties reported by physician and nurse anaesthetists resemble established barriers to incident reporting and may similarly act as barriers to quality documentation during anaesthesia. Further studies should investigate if these perceived obstacles have a causal impact on quality reporting in anaesthesia.

TRIAL REGISTRATION

ClinicalTrials.gov identifier is NCT01524484. Registration date: January 21, 2012.

A 90-year-old patient presenting with postoperative hypotension and a new murmur: a case report

INTRODUCTION

Hospitalists are frequently consulted on postoperative patients with hypotension. Postoperative hypotension is common and can be due to variety of causes. Systolic anterior motion of the mitral valve leading to left ventricular outflow tract obstruction is a rare cause of postoperative hypotension and can occur without prior structural heart disease. A high index of suspicion can lead to early recognition of this unique condition.

CASE PRESENTATION

A 90-year-old Caucasian woman with no known structural heart abnormality was admitted to the intensive care unit with hypotension after a left hip arthroplasty revision. A transthoracic echocardiogram revealed systolic anterior motion of the mitral valve and dynamic left ventricular outflow tract obstruction as the likely cause of her hypotension. Our patient was treated with fluid resuscitation and phenylephrine with improvement in blood pressure. A repeat echocardiogram on postoperative day 5 showed resolution of the left ventricular outflow tract obstruction. Intraoperative vasodilatation and volume loss that caused underfilling of the left ventricle likely led to dynamic outflow tract obstruction in our patient.

CONCLUSIONS

Hospitalists should be aware of systolic anterior motion of the mitral valve as a rare peri-operative complication in patients with or without underlying cardiac pathology as it is treated differently than other causes of peri-operative hypotension. Clinical suspicion, early recognition, and prompt treatment can improve clinical outcomes in these patients.

Electrical stimulation of the ventral tegmental area induces reanimation from general anesthesia

BACKGROUND

Methylphenidate or a D1 dopamine receptor agonist induces reanimation (active emergence) from general anesthesia. The authors tested whether electrical stimulation of dopaminergic nuclei also induces reanimation from general anesthesia.

METHODS

In adult rats, a bipolar insulated stainless steel electrode was placed in the ventral tegmental area (VTA, n = 5) or substantia nigra (n = 5). After a minimum 7-day recovery period, the isoflurane dose sufficient to maintain loss of righting was established. Electrical stimulation was initiated and increased in intensity every 3 min to a maximum of 120 µA. If stimulation restored the righting reflex, an additional experiment was performed at least 3 days later during continuous propofol anesthesia. Histological analysis was conducted to identify the location of the electrode tip. In separate experiments, stimulation was performed in the prone position during general anesthesia with isoflurane or propofol, and the electroencephalogram was recorded.

RESULTS

To maintain loss of righting, the dose of isoflurane was 0.9% ± 0.1 vol%, and the target plasma dose of propofol was 4.4 ± 1.1 µg/ml (mean ± SD). In all rats with VTA electrodes, electrical stimulation induced a graded arousal response including righting that increased with current intensity. VTA stimulation induced a shift in electroencephalogram peak power from δ (<4 Hz) to θ (4-8 Hz). In all rats with substantia nigra electrodes, stimulation did not elicit an arousal response or significant electroencephalogram changes.

CONCLUSIONS

Electrical stimulation of the VTA, but not the substantia nigra, induces reanimation during general anesthesia with isoflurane or propofol. These results are consistent with the hypothesis that dopamine release by VTA neurons, but not substantia nigra neurons, induces reanimation from general anesthesia.

Pediatric fasting times before surgical and radiologic procedures: benchmarking institutional practices against national standards

Prolonged preoperative fasting can be associated with adverse outcomes, particularly in children. Our aims were to assess the time pediatric patients fasted prior to surgical or radiologic procedures and evaluate whether fasting (NPO) orders complied with national guidelines. We measured NPO start time, time of last intake, and time test or surgery was scheduled, took place, or was cancelled in 219 pediatric patients. Findings demonstrate that pediatric patients experienced prolonged fasting before procedures and that the majority of NPO orders were non-compliant with national guidelines. We have developed strategies to reduce fasting times and ensure compliance with recommended national fasting standards.

Impact of national guidelines on reporting anaphylaxis during anaesthesia -- an outcome audit

AIMS

Anaphylaxis during anaesthesia is a rare and potentially fatal event. Adequate reporting and investigation of anaphylaxis associated with anaesthesia results in improved patient safety and outcomes. Guidelines from the Association of Anaesthetists of Great Britain and Ireland (AAGBI) designed to improve this process were first issued in 1990 and updated in 1995, 2003 and 2008. In a setting where no formal guideline was previously in place, we compared the reporting and investigation of anaphylaxis in a large hospital before and after the introduction of the 2008 guideline.

METHODS

A retrospective outcome audit was conducted to compare data from 12 patients referred from April 2006 to May 2008 prior to release of the 2008 AAGBI guidance, with 53 patients referred from 2008 until April 2011. Data were collected using the AAGBI Anaphylaxis Referral Form.

RESULTS

There was an increase in the number of referrals for suspected anaphylaxis following implementation of the AAGBI guidance. The clinical features observed in patients were consistent with previous studies. There was improved documentation of referral to local and national databases. Most cases resulted in cancellation of surgery, and there were no patient deaths. A substantial increase in the number of patients with amoxicillin allergy was noted in the second time period, which was linked to a change in the local perioperative antibiotic policy.

CONCLUSIONS

Implementation of the AAGBI guidelines locally in a large hospital in 2008 resulted in an improved awareness of the importance of reporting and investigation of suspected anaphylaxis under anaesthesia. This tool was implemented coincidentally with the change in hospital antibiotic prophylaxis and enabled the cases detected to be accurately recorded and investigated. This led to a change in the hospital antibiotic policy for surgical prophylaxis. Implementation of structured guidance from a national anaesthesia organisation enhances recognition of the clinical features of anaphylaxis, increases number and completeness of referrals and more thorough immunological investigation, leading to improved patient safety during anaesthesia.

Evolution of anaesthesia care and related events between 1996 and 2010 in Switzerland

BACKGROUND

Anaesthesia Databank Switzerland (ADS) is a voluntary data registry introduced in 1996. Its ultimate goal is to promote quality in anaesthesiology.

METHODS

The ADS registry analyses routinely recorded adverse events and provides benchmark comparisons between anaesthesia departments. Data collection comprises a set of 31 variables organised into three modules, one mandatory and two optional.

RESULTS

In 2010, the database included 2,158,735 anaesthetic procedures. Over time, the proportions of older patients have increased, the largest group being aged 50-64 years. The percentage of patients with American Society of Anesthesiologists (ASA) status 1 has decreased while the percentage of ASA status 2 or 3 patients has increased. The most frequent comorbidities recorded were hypertension (21%), smoking (16%), allergy (15%) and obesity (12%). Between 1996 and 2010, 125,579 adverse events were recorded, of which 34% were cardiovascular, 7% respiratory, 39% technical and 20% non-specific. The most severe events were resuscitation (50%), oliguria (22%), myocardial ischaemia (17%) and haemorrhage (10%).

CONCLUSION

Routine ADS data collection contributes to the monitoring of trends in anaesthesia care in Switzerland. The ADS system has proved to be usable in daily practice, although this remains a constant challenge that is highly dependent on local quality management and quality culture. Nevertheless, success in developing routine regular feedback to users to initiate discussions about anaesthetic events would most likely help strengthen departmental culture regarding safety and quality of care.

[Systematic collection and analysis of intraoperative anaesthetic-related problems]

OBJECTIVE

The purpose of the study was to systematically collect and analyse the frequency, type and severity of all untoward intraoperative anaesthetic-related problems in a hospital over a 6-month period.

METHODS

An observational, systematic, prospective, and cross sectional study was conducted on the events and their risk factors. The study is based on a system in which anaesthesia-related data are recorded from all anaesthetic cases on a routine basis, including sedation and obstetric analgesia. The variables were demographic, procedural data, and a checklist with problem type and severity. Data were analysed using chi-square, Fisher's test, or Student's test. A P<.05 was considered statistically significant.

RESULTS

The frequency of intraoperative anaesthetic-related problems was 17.2%, with 1.3 anaesthetic problems per case, being 9 times more frequent the adverse effects with low severity grade. During anaesthesia, respiratory problems occurred in 13, circulatory problems in 8, and technical problems in 2 out of every 100 procedures. The factors associated with the patient in whom the anaesthetic problem occurred were: the use of general anaesthesia, supraumbilical surgery, and a higher preoperative anaesthetic risk.

CONCLUSIONS

Use of a systematic intraoperative anaesthetic-related database with a checklist of problems and severity plays an important part in quality assurance strategies. An analysis of non-fatal problems provides a basis for establishing corrective strategies before significant morbidity occurs, and by separating the surgical and anaesthesia problems.

Evaluation of the incidence, risk factors, and impact on patient outcomes of postintubation hemodynamic instability

OBJECTIVES

Postintubation hemodynamic instability (PIHI) is a potentially life-threatening adverse event of emergent endotracheal intubation. The objectives of this study were to determine the incidence, risk factors, and impact on patient outcomes associated with PIHI in intubations performed in emergency medicine.

METHODS

A structured chart audit was performed of all consecutive adult patients requiring emergent endotracheal intubations over a 16-month period at a tertiary care emergency department (ED). Data collection included medications, comorbidities, vital signs in the 30 minutes before and after intubation, hospital length of stay, and in-hospital mortality. PIHI was defined as a decrease in systolic blood pressure (SBP) to ≤ 90 mm Hg, a decrease in SBP of ≥ 20% from baseline, a decrease in mean arterial pressure to ≤ 65 mm Hg, or the initiation of any vasopressor medication at any time in the 30 minutes following intubation.

RESULTS

Overall, 218 patients intubated in the ED were identified, and 44% (96 of 218) developed PIHI. On multivariate analysis, increasing age (OR 1.03, 95% CI 1.01-1.05), chronic obstructive pulmonary disease (OR 3.00, CI 1.19-7.57), and pre-emergent endotracheal intubation hemodynamic instability (OR 2.52, 95% CI 1.27-4.99) were associated with the development of PIHI. The use of a neuromuscular blocking medication was associated with a decreased incidence of PIHI (OR 0.34, 95% CI 0.16-0.75).

CONCLUSIONS

Based on our data, postintubation hypotension occurs in a significant proportion of ED patients requiring emergent airway control. Further investigation is needed to confirm the factors we found to be associated with PIHI and to determine if PIHI is associated with increased morbidity and mortality.

Risk factors for reintubation in the post-anaesthetic care unit: a case-control study

BACKGROUND

Risk factors for reintubation in post-anaesthetic care units related to anaesthetic processes have not previously been reported. Our goal was to identify risk factors for reintubation in general surgical patients.

METHODS

A time-matched, case-control study was conducted on anaesthetic patients between 2001 and 2011. One hundred and sixty-four reintubated patients were compared with 656 randomly selected controls.

RESULTS

Independent risk factors for reintubation were age <1 yr vs age 30-49 yr [odds ratio (OR)=16.4, 95% confidence interval (CI)=5.7-47.7], chronic pulmonary disease (OR=2.1, CI=1.1-4.0), preoperative hypoalbuminaemia (OR=4.9, CI=2.4-10), creatinine clearance <24 vs >60 (OR=4.1, CI=1.2-13.4), emergency case (OR=1.8, CI=1.0-3.1), operative time >3 vs <1 h (OR=3.0, CI=1.5-6.2), airway surgery (OR=32.2, CI=13.6-76), head and neck surgery (OR=3.4, CI=1.8-6.2), cardiac surgery (OR=3.8, CI=1.1-13.4), thoracic surgery (OR=6.3, CI=1.9-21.2), cardiac catheterization (OR=2.5, CI=1.1-5.5), ASA physical status III (OR=3.8, CI=1.4-10), and the use of certain types of neuromuscular blocking agent (P<0.001).

CONCLUSIONS

Age <1 yr, chronic pulmonary disease, preoperative hypoalbuminaemia, and renal insufficiency were patient factors for reintubation. Emergency case, head and neck, cardiothoracic and airway surgery, and operative time >3 h were operative factors, while certain neuromuscular blocking agents and ASA physical status III were anaesthetic factors for reintubation.