Routine preoperative gastric emptying is seldom indicated. A study of 85,594 anaesthetics with special focus on aspiration pneumonia

Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR), Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management. Part I

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.

Incidence, causes, and management of failed awake fibreoptic intubation-A retrospective study of 833 procedures

Awake fibreoptic intubation has been considered a gold standard in the management of the difficult airway. However, failure may cause critical situations. The aim of this study was to investigate the incidence and causes of failed awake fibreoptic intubation at a tertiary care hospital. The study was conducted at St. Olav University Hospital in Trondheim, Norway. Problems occurring during anaesthesia are routinely recorded in the electronic anaesthesia information system (Picis Clinical Solutions Inc.), including difficult intubations. We applied text search on all anaesthesia records between 2011 and 2021 and identified 833 awake fibreoptic intubations. The anaesthesia records were examined to identify failed awake fibreoptic intubations, the cause of failure and how the airway ultimately was secured. Among 233,938 patients who received anaesthesia, 90,397 received tracheal intubation and 833 received awake fibreoptic intubation. Twenty-nine of the procedures failed. In nine patients the failure caused loss of airway control with desaturation and hypoventilation. The major causes of failure were dislodged tube after induction of general anaesthesia (n = 8), patient distress (n = 5), tube not able to pass (n = 5), and airway bleeding (n = 3). The situations were primarily solved using direct laryngoscopy, with or without bougie, or with video laryngoscopy. Tracheostomy was performed in four patients. Awake fibreoptic intubation failed in 3.5% of patients, most often due to dislocation, problems passing the tracheal tube, or patient discomfort. The failure rate was higher than in previous studies.

A cross sectional, observational study to evaluate the surgeons' knowledge and perspective on preoperative fasting guidelines in a tertiary care teaching hospital in Southern India

Background and Aims

The preoperative fasting orders given by the Anesthesiologists as per ASA and Enhanced Recovery After Surgery protocol, are often modified by the surgeons, for practical convenience, which can end up with patients being starved for prolonged periods of time. Hence, this study was conducted among various specialty surgical colleagues, to evaluate the knowledge and their perspective regarding patients' preoperative fasting guidelines.

Material and Methods

A validated questionnaire was distributed to 68 surgeons belonging to various surgical specialties, which included consultants and postgraduate residents. The surgeons were grouped as surgeons operating only on children, only on adults, and on adults and children (mixed). Data were summarized using the mean (SD)/median for continuous variables and categorical data were expressed as frequency and percentage. The difference in knowledge score, among the surgeons of three groups, was analyzed using ANOVA, with Bonferroni as post hoc.

Results

This study shows an overall decrease in knowledge (score of 6.13 ± 1.74) about preoperative fasting guidelines among surgeons. We found that the level of knowledge about preoperative fasting guidelines and complications was higher among surgeons who operate only on children (score of 7.05) as compared to surgeons operating only on adults (score 5.5) and adults and children (mixed) (score 6.1), which was statistically significant (P = 0.013). We found no difference in knowledge level based on designation and gender. All the surgeons uniformly had the perspective that patients have to be kept fasting preoperatively.

Conclusion

Preoperative fasting orders for all surgical patients, especially for vulnerable patients such as children and geriatrics, should be administered by the anesthesiologist or surgeon who is familiar with fasting guidelines. We intend to raise the awareness of fasting guidelines of surgical colleagues by putting up placards and posters in the wards.

[Intraoperative Aspiration]

术中误吸是外科手术中常见的肺部并发症，麻醉和体位是导致术中误吸的主要因素。近年来，围手术期肺保护已受到外科和麻醉医师的广泛关注，如何加速术后康复进程，减少相关并发症发生，显著改善患者预后已成为当前外科治疗的主要目标。本文将以术中误吸为重点，从解剖、病理生理、表现、诊断、处理和预防等方面展开综述。

Use of Handheld Point-of-Care Ultrasound in Emergency Airway Management

Emergency airway management (EAM) is associated with a high rate of complications, morbidity, and mortality. Handheld point-of-care ultrasound shows promise as an emerging technology to facilitate rapid screening for difficult laryngoscopy, identify the cricothyroid membrane for potential cricothyroidotomy, and assess for increased aspiration risk, as well as provide confirmation of proper endotracheal tube positioning. This review summarizes the available evidence for the use of point-of-care ultrasound in EAM, provides an algorithm to facilitate its incorporation into existing EAM practice to improve patient safety, and serves as a framework for future validation studies.

Perioperative aspiration events in children: A report from the Wake Up Safe Collaborative

BACKGROUND

Perioperative aspiration, while rare, is a serious complication of anesthetic care. Consequences of aspiration may include physical obstruction, wheezing, and pneumonia, resulting in mild to severe hypoxemia and even death.

AIM

We used a multi-institutional registry of pediatric patients to identify factors that influence the rate and resulting harm of perioperative pulmonary aspiration.

METHODS

The Wake Up Safe registry was queried for all severe adverse events reported from 29 institutions from 2010 to 2017. Aspiration events were identified through the "respiratory adverse event" data entry form or through free text search. Multivariable regression was used to predict aspiration events, and contributory factors were identified by reviewing free text case comments.

RESULTS

Analysis included 2 440 810 anesthetics administered involving patients ≤18 years of age. There were 135 pulmonary aspiration events, for an incidence of 0.006%. Within these 135 cases, 110 cases (82%) resulted in escalation of care and 51 (38%) resulted in patient harm, including 2 deaths (1.5%). In multivariable analysis, patients undergoing emergency surgery (OR 2.0 [1.2-3.5]) or with higher ASA status were more likely to experience aspiration (ASA 3 (OR 5.0 [2.6-9.1]); ASA ≥ 4 (OR 5.5 [3.8-16.8])). Noted causes of aspiration included gastrointestinal comorbid conditions (19%), postcoughing event or laryngospasm (14%), nil per os (NPO) violation (11%), blood or secretions in the airway following or during the procedure (6%), and oral premedication reaction (3%).

CONCLUSION

Although infrequent, death was reported as a consequence of perioperative aspiration in two patients. The frequency with which NPO violations were identified as a potential cause of aspiration highlights the struggles institutions face with adherence to NPO regulations, as these cases may be preventable. Furthermore, preventive measures may be needed to address other common causes of aspiration, such as gastrointestinal comorbid conditions.

Evaluating the Safety and Efficacy of Intraoperative Enteral Nutrition in Critically Ill Burn Patients: A Systematic Review and Meta-analysis

Major burn injuries incite a hypermetabolic response, and the initiation of early enteral nutrition is the standard of care in patients with large burns and contributes to improved outcomes. Perioperative fasting is a common cause of caloric deficits in burn patients and can be obviated with intraoperative enteral nutrition. However, the risks and benefits of this practice are unknown, and there is a concern for aspiration. We conducted a systematic review and meta-analysis to evaluate the safety and efficacy of intraoperative enteral nutrition. We performed a systematic literature search using PubMed, Scopus, and OvidSP MEDLINE databases. We identified studies that evaluated the effects of intraoperative enteral nutrition in adult burn patients compared to those undergoing routine perioperative fasting. We performed a meta-analysis on the incidence of mortality, pneumonia, wound infections, and aspiration in burn patients receiving intraoperative enteral nutrition. We identified seven articles for qualitative review and four for quantitative review (N = 83 patients). There were no statistically significant increases in the risk of mortality (odds ratio [OR] = 1.28, 95% confidence interval [CI]: 0.49, 3.31), wound infections (OR = 0.71, 95% CI: 0.16, 3.24), pneumonia (OR = 2.1, 95% CI: 0.7, 6.1), and aspiration (OR = 1.14, 95% CI: 0.07, 18.75) in patients receiving intraoperative enteral nutrition. Within individual studies, intraoperative enteral nutrition patients received significantly more calories than standard fasting patients. Intraoperative enteral nutrition may increase nutritional intake in burn patients without an increase in complications; however, this is based on limited studies. Randomized controlled trials are needed before recommendations on intraoperative enteral nutrition practice can be made.

An international multidisciplinary consensus statement on fasting before procedural sedation in adults and children

The multidisciplinary International Committee for the Advancement of Procedural Sedation presents the first fasting and aspiration prevention recommendations specific to procedural sedation, based on an extensive review of the literature. These were developed using Delphi methodology and assessment of the robustness of the available evidence. The literature evidence is clear that fasting, as currently practiced, often substantially exceeds recommended time thresholds and has known adverse consequences, for example, irritability, dehydration and hypoglycaemia. Fasting does not guarantee an empty stomach, and there is no observed association between aspiration and compliance with common fasting guidelines. The probability of clinically important aspiration during procedural sedation is negligible. In the post-1984 literature there are no published reports of aspiration-associated mortality in children, no reports of death in healthy adults (ASA physical status 1 or 2) and just nine reported deaths in adults of ASA physical status 3 or above. Current concerns about aspiration are out of proportion to the actual risk. Given the lower observed frequency of aspiration and mortality than during general anaesthesia, and the theoretical basis for assuming a lesser risk, fasting strategies in procedural sedation can reasonably be less restrictive. We present a consensus-derived algorithm in which each patient is first risk-stratified during their pre-sedation assessment, using evidence-based factors relating to patient characteristics, comorbidities, the nature of the procedure and the nature of the anticipated sedation technique. Graded fasting precautions for liquids and solids are then recommended for elective procedures based upon this categorisation of negligible, mild or moderate aspiration risk. This consensus statement can serve as a resource to practitioners and policymakers who perform and oversee procedural sedation in patients of all ages, worldwide.

Periprocedural pulmonary aspiration: An analysis of medical malpractice cases and alleged causative factors

RATIONALE AIMS AND OBJECTIVES

Pulmonary aspiration is a feared complication of anaesthesia that is associated with significant morbidity and mortality. Within the small existing body of literature on medical malpractice claims related to periprocedural aspiration, very little information is available regarding the case-specific factors that were alleged to contribute to each aspiration event.

METHODS

This study searched an extensive nationwide database of medical malpractice claims and identified 43 relating to periprocedural pulmonary aspiration.

RESULTS

The most common mechanism of causation cited in these claims (37%) was the failure to secure the airway with an endotracheal tube (ETT) when an elevated aspiration risk existed, most commonly because endotracheal intubation was not originally selected as part of the anaesthetic plan. The second most common alleged category of causation (33%) was the failure to perform a proper rapid-sequence induction and/or place a nasogastric tube (NGT) for decompression prior to induction. An equal amount of cases resulted in defendant versus plaintiff verdicts (44.2% each), while a settlement was reached in the remaining 11.6% of cases.

CONCLUSION

These findings are generalizable to clinical practice improvement on a broader scale. They demonstrate the need to develop reliable, high-sensitivity tests for detecting elevated risk before clinicians can be expected to take special steps to protect susceptible patients, and they also show that medical malpractice can be alleged because of failure to uphold currently accepted standards of care even when the published evidence for those standards is weak. This study demonstrates that careful review of medical malpractice litigation can elucidate common contributory factors and facilitate improvements in clinical practice and decision-making.

Bag-Mask Ventilation during Tracheal Intubation of Critically Ill Adults

BACKGROUND

Hypoxemia is the most common complication during tracheal intubation of critically ill adults and may increase the risk of cardiac arrest and death. Whether positive-pressure ventilation with a bag-mask device (bag-mask ventilation) during tracheal intubation of critically ill adults prevents hypoxemia without increasing the risk of aspiration remains controversial.

METHODS

In a multicenter, randomized trial conducted in seven intensive care units in the United States, we randomly assigned adults undergoing tracheal intubation to receive either ventilation with a bag-mask device or no ventilation between induction and laryngoscopy. The primary outcome was the lowest oxygen saturation observed during the interval between induction and 2 minutes after tracheal intubation. The secondary outcome was the incidence of severe hypoxemia, defined as an oxygen saturation of less than 80%.

RESULTS

Among the 401 patients enrolled, the median lowest oxygen saturation was 96% (interquartile range, 87 to 99) in the bag-mask ventilation group and 93% (interquartile range, 81 to 99) in the no-ventilation group (P = 0.01). A total of 21 patients (10.9%) in the bag-mask ventilation group had severe hypoxemia, as compared with 45 patients (22.8%) in the no-ventilation group (relative risk, 0.48; 95% confidence interval [CI], 0.30 to 0.77). Operator-reported aspiration occurred during 2.5% of intubations in the bag-mask ventilation group and during 4.0% in the no-ventilation group (P = 0.41). The incidence of new opacity on chest radiography in the 48 hours after tracheal intubation was 16.4% and 14.8%, respectively (P = 0.73).

CONCLUSIONS

Among critically ill adults undergoing tracheal intubation, patients receiving bag-mask ventilation had higher oxygen saturations and a lower incidence of severe hypoxemia than those receiving no ventilation. (Funded by Vanderbilt Institute for Clinical and Translational Research and others; PreVent ClinicalTrials.gov number, NCT03026322.).

Patients’ Understanding of Pre-operative Fasting

We aimed to assess elective day surgery patients’ understanding of the reason for pre-operative fasting. One hundred adult patients presenting to the peri-operative unit for day procedures requiring general anaesthesia were surveyed before discharge. All day-stay, adult patients able to complete a questionnaire in English were included. Only 22% (95%CI [14,31]) of patients correctly understood why fasting was necessary. Patients who did not understand were nearly five times more likely to underrate the importance of compliance (risk ratio 4.65, 95%CI [1.2,18]). Two per cent (95%CI [0.2,7]) of patients reported actual non-compliance, and 4% (95%CI [1,10]) stated they would consider misrepresenting their fasting status if it was inconvenient for them to have their surgery postponed. The results of this study suggest a need to better inform day surgery patients about the reason for pre-operative fasting. A better understanding of the need for pre-operative fasting may lead to improved compliance and patient safety.

Identification of perioperative pulmonary aspiration in children using quality assurance and hospital administrative billing data

BACKGROUND

Perioperative aspiration is a rare but potentially devastating complication, occurring in 1-10 per 10 000 anesthetics based on studies of quality assurance databases. Quality assurance reporting is known to underestimate the incidence of adverse outcomes, but few large studies use supplementary data sources. This study aims to identify the incidence of and risk factors for perioperative aspiration in children using quality assurance data supplemented by administrative billing records, and to examine the utility of billing data as a supplementary data source.

METHODS

Aspiration events for children receiving anesthesia at a tertiary care pediatric hospital between 2008 and 2014 were identified using (i) a perioperative quality assurance database and (ii) hospital administrative billing records with International Classification of Diseases, Ninth Revision Clinical Modification coded diagnoses of aspiration. Records were subject to review by pediatric anesthesiologists. Following identification of all aspiration events, the incidence of perioperative aspiration was calculated and risk factors were assessed.

RESULTS

47 272 anesthetic cases were evaluated over 7 years. The quality assurance database identified 20 cases of perioperative aspiration occurring in surgical inpatients, same-day admissions, and outpatients. Using hospital administrative data (which excludes outpatients with shorter than a 24-hour stay), 9 cases of perioperative aspiration were identified of which 6 had not been found through quality assurance data. Overall, International Classification of Diseases, Ninth Revision coding demonstrated a positive predictive value of 94.5% for any aspiration event; however, positive predictive value was <4% for perioperative aspiration. A total incidence of 5.5 perioperative aspirations per 10 000 (95% CI: 3.7-8.0 per 10 000) anesthetics was found.

CONCLUSION

Quality assurance data offer an efficient way to measure the incidence of rare events, but may underestimate perioperative complications. International Classification of Diseases, Ninth Revision codes for aspiration used as a secondary data source were nonspecific for perioperative aspiration, but when combined with record review yielded a 30% increase in identified cases of aspiration over quality assurance data alone. The use of administrative data therefore holds potential for supplementing quality assurance studies of rare complications.

Acute Intraoperative Pulmonary Aspiration

Acute intraoperative aspiration is a potentially fatal complication with significant associated morbidity. Patients undergoing thoracic surgery are at increased risk for anesthesia-related aspiration, largely due to the predisposing conditions associated with this complication. Awareness of the risk factors, predisposing conditions, maneuvers to decrease risk, and immediate management options by the thoracic surgeon and the anesthesia team is imperative to reducing risk and optimizing patient outcomes associated with acute intraoperative pulmonary aspiration. Based on the root-cause analyses that many of the aspiration events can be traced back to provider factors, having an experienced anesthesiologist present for high-risk cases is also critical.

The role of perioperative chewing gum on gastric fluid volume and gastric pH: a meta-analysis

STUDY OBJECTIVE

To determine if preoperative gum chewing affects gastric pH and gastric fluid volume.

DESIGN

Systematic review and meta-analysis.

METHODS

Data sources included Cochrane, PubMed, and EMBASE databases from inception to June 2012 and reference lists of known relevant articles without language restriction. Randomized controlled trials in which a treatment group that chewed gum was compared to a control group that fasted were included. Relevant data, including main outcomes of gastric fluid volume and gastric pH, were extracted.

RESULTS

Four studies involving 287 patients were included. The presence of chewing gum was associated with small but statically significant increases in gastric fluid volume (mean difference = 0.21 mL/kg; 95% confidence interval, 0.02-0.39; P = .03) but not in gastric pH (mean difference = 0.11 mL/kg; 95% confidence interval, -0.14 to 0.36; P = .38). Gastric fluid volume and gastric pH remained unchanged in subgroup analysis by either sugar or sugarless gum type.

CONCLUSIONS

Chewing gum in the perioperative period causes small but statically significant increases in gastric fluid volume and no change in gastric pH. The increase in gastric fluid most likely is of no clinical significance in terms of aspiration risk for the patient. Elective surgery should not necessarily be canceled or delayed in healthy patients who accidentally chew gum preoperatively.

Effectiveness of milrinone for cardiogenic shock due to massive pulmonary aspiration: a case report

Pulmonary aspiration of gastric contents is one of the most frightening complications during anesthesia. Although pulmonary aspiration of gastric contents in general surgical patients is not common and resulting long-term morbidity and mortality are rare, severe hypoxemia and other sequelae of pulmonary aspiration continue to be reported. We report a case of massive aspiration of gastric contents during induction of general anesthesia, resulting in cardiac arrest due to severe pulmonary hypertension and myocardial infarction. Sustained cardiac arrest and shock that did not respond the conventional resuscitation was successfully treated using milrinone. The patient was discharged without complications in 20 days.

Perioperative hypoxemia is common with horizontal positioning during general anesthesia and is associated with major adverse outcomes: a retrospective study of consecutive patients

Background

Reported perioperative pulmonary aspiration (POPA) rates have substantial variation. Perioperative hypoxemia (POH), a manifestation of POPA, has been infrequently studied beyond the PACU, for patients undergoing a diverse array of surgical procedures.

Methods

Consecutive adult patients with ASA I-IV and pre-operative pulmonary stability who underwent a surgical procedure requiring general anesthesia were investigated. Using pulse oximetry, POH was documented in the operating room and during the 48 hours following PACU discharge. POPA was the presence of an acute pulmonary infiltrate with POH.

Results

The 500 consecutive, eligible patients had operative body-positions of prone 13%, decubitus 8%, sitting 1%, and supine/lithotomy 78%, with standard practice of horizontal recumbency. POH was found in 150 (30%) patients. Post-operative stay with POH was 3.7 ± 4.7 days and without POH was 1.7 ± 2.3 days (p < 0.0001). POH rate varied from 14% to 58% among 11 of 12 operative procedure-categories. Conditions independently associated with POH (p < 0.05) were acute trauma, BMI, ASA level, glycopyrrolate administration, and duration of surgery. POPA occurred in 24 (4.8%) patients with higher mortality (8.3%), when compared to no POPA (0.2%; p = 0.0065). Post-operative stay was greater with POPA (7.7 ± 5.7 days), when compared to no POPA (2.0 ± 2.9 days; p = 0.0001). Conditions independently associated with POPA (p < 0.05) were cranial procedure, ASA level, and duration of surgery. POPA, acute trauma, duration of surgery, and inability to extubate in the OR were independently associated with post-operative stay (p < 0.05). POH, gastric dysmotility, acute trauma, cranial procedure, emergency procedure, and duration of surgery had independent correlations with post-operative length of stay (p < 0.05).

Conclusions

Adult surgical patients undergoing general anesthesia with horizontal recumbency have substantial POH and POPA rates. Hospital mortality was greater with POPA and post-operative stay was increased for POH and POPA. POH rates were noteworthy for virtually all categories of operative procedures and POH and POPA were independent predictors of post-operative length of stay. A study is needed to determine if modest reverse-Trendelenburg positioning during general anesthesia has a relationship with reduced POH and POPA rates.

Gastric tubes and airway management in patients at risk of aspiration: history, current concepts, and proposal of an algorithm

Rapid sequence induction and intubation (RSII) and awake tracheal intubation are commonly used anesthetic techniques in patients at risk of pulmonary aspiration of gastric or esophageal contents. Some of these patients may have a gastric tube (GT) placed preoperatively. Currently, there are no guidelines regarding which patient should have a GT placed before anesthetic induction. Furthermore, clinicians are not in agreement as to whether to keep a GT in situ, or to partially or completely withdraw it before anesthetic induction. In this review we provide a historical perspective of the use of GTs during anesthetic induction in patients at risk of pulmonary aspiration. Before the introduction of cricoid pressure (CP) in 1961, various techniques were used including RSII combined with a head-up tilt. Sellick initially recommended the withdrawal of the GT before anesthetic induction. He hypothesized that a GT increases the risk of regurgitation and interferes with the compression of the upper esophagus during CP. He later modified his view and emphasized the safety of CP in the presence of a GT. Despite subsequent studies supporting the effectiveness of CP in occluding the esophagus around a GT, Sellick's early view has been perpetuated by investigators who recommend partial or complete withdrawal of the GT. On the basis of available information, we have formulated an algorithm for airway management in patients at risk of aspiration of gastric or esophageal contents. The approach in an individual patient depends on: the procedure; type and severity of the underlying pathology; state of consciousness; likelihood of difficult airway; whether or not the GT is in place; contraindications to the use of RSII or CP. The algorithm calls for the preanesthetic use of a large-bore GT to remove undigested food particles and awake intubation in patients with achalasia, and emptying the pouch by external pressure and avoidance of a GT in patients with Zenker diverticulum. It also stipulates that in patients with gastric distension without predictable airway difficulties, a clinical and imaging assessment will determine the need for a GT and in severe cases an attempt to insert a GT should be made. In the latter cases, the success of placement will indicate whether to use RSII or awake intubation. The GT should not be withdrawn and should be connected to suction during induction. Airway management and the use of GTs in the surgical correction of certain gastrointestinal anomalies in infants and children are discussed.

Airway management in obese patients

The well-known difficulties in airway management in obese patients are caused by obesity-related airways and respiratory changes. Anesthesiologists confront a number of troubles, including rapid oxygen desaturation, difficulty with laryngoscopy/intubation and mask ventilation, and increased susceptibility to the respiratory depressant effects of anesthetic drugs. Preoperative assessment of the airways in the obese should include examination of specific predictors of difficult mask ventilation other than those for difficult intubation. Difficulties in airway management are decreased after providing optimal preoxygenation and positioning ("ramped"). Other strategies may include availability of alternative airway management devices, including new video laryngoscopes that significantly improve the visualization of the larynx and thereby facilitate intubation. If awake intubation is mandatory, it may be performed with fibrobronchoscope after providing an adequate topical anesthesia and sedation with short-acting drugs, such as remifentanil. Succinylcholine for rapid sequence induction might be replaced by rocuronium where sugammadex is available for reversal. A complete reversal of neuromuscular block, measured by train-of-four monitoring, should be obtained before extubation, which requires a fully awake patient in the same position with airway equipment used for intubation.

The safety of deep sedation without intubation for abortion in the outpatient setting

STUDY OBJECTIVE

To determine the rate of perioperative pulmonary aspiration in patients undergoing first and second-trimester surgical abortion during deep sedation with propofol, without intubation.

DESIGN

Retrospective review of cases of surgical and anesthetic complications reported to the Office of Quality Management of the surgical facility between August 1, 2001 and April 30, 2008.

SETTING

Large urban surgical abortion outpatient facility.

MEASUREMENTS

The medical records of all surgical abortion patients who underwent hospital transfer were reviewed. From billing records, all patients who underwent abortion during deep sedation were identified. The primary outcome was the rate of perioperative pulmonary aspiration. Secondary outcomes included the rates of other anesthesia-related adverse events resulting in hospital transfer.

MAIN RESULTS

During the 81-month study period, the facility performed 62,125 surgical abortions during deep sedation, including 11,039 second-trimester abortions. Only one patient received endotracheal intubation. No cases of perioperative pulmonary aspiration occurred.

CONCLUSIONS

Deep sedation without intubation is a viable method of anesthesia for both first and second-trimester surgical abortions in the outpatient setting.

Scandinavian clinical practice guidelines on general anaesthesia for emergency situations

Emergency patients need special considerations and the number and severity of complications from general anaesthesia can be higher than during scheduled procedures. Guidelines are therefore needed. The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine appointed a working group to develop guidelines based on literature searches to assess evidence, and a consensus meeting was held. Consensus opinion was used in the many topics where high-grade evidence was unavailable. The recommendations include the following: anaesthesia for emergency patients should be given by, or under very close supervision by, experienced anaesthesiologists. Problems with the airway and the circulation must be anticipated. The risk of aspiration must be judged for each patient. Pre-operative gastric emptying is rarely indicated. For pre-oxygenation, either tidal volume breathing for 3 min or eight deep breaths over 60 s and oxygen flow 10 l/min should be used. Pre-oxygenation in the obese patients should be performed in the head-up position. The use of cricoid pressure is not considered mandatory, but can be used on individual judgement. The hypnotic drug has a minor influence on intubation conditions, and should be chosen on other grounds. Ketamine should be considered in haemodynamically compromised patients. Opioids may be used to reduce the stress response following intubation. For optimal intubation conditions, succinylcholine 1-1.5 mg/kg is preferred. Outside the operation room, rapid sequence intubation is also considered the safest method. For all patients, precautions to avoid aspiration and other complications must also be considered at the end of anaesthesia.

Pre-operative fasting: a nationwide survey of German anaesthesia departments

BACKGROUND

Shorter pre-operative fasting improves clinical outcome without an increased risk. Since October 2004, German Anaesthesiology Societies have officially recommended a fast of 2 h for clear fluids and 6 h for solid food before elective surgery. We conducted a nationwide survey to evaluate the current clinical practice in Germany.

METHODS

Between July 2006 and January 2007, standardized questionnaires were mailed to 3751 Anaesthesiology Society members in leading positions requesting anonymous response.

RESULTS

The overall response rate was 66% (n=2418). Of those, 2148 (92%) claimed familiarity with the new guidelines. About a third (n=806, 34%) reported full adherence to the new recommendations, whereas 1043 (45%) reported an eased fasting practice. Traditional Nil per os after midnight was still recommended by 157 (7%). Commonest reasons reported for adopting the new guidelines were: 'improved pre-operative comfort' (84%), and 'increased patient satisfaction' (83%); reasons against were: 'low flexibility in operation room management' (19%), and 'increased risk of aspiration' (13%).

CONCLUSION

Despite the apparent understanding of the benefits from reduced pre-operative fasting, full implementation of the guidelines remains poor in German anaesthesiology departments.

No evidence for decreased incidence of aspiration after rapid sequence induction

PURPOSE

The purpose of this structured, evidence-based, clinical update was to determine if rapid sequence induction is a safe or effective technique to decrease the risk of aspiration or other complications of airway management.

SOURCE

In June 2006 a structured search of MEDLINE from 1966 to present using OVID software was undertaken with the assistance of a reference librarian. Medical subject headings and text words describing rapid sequence induction or intubation (RSI), crash induction or intubation, cricoid pressure and emergency airway intubation were employed. OVID's therapy (sensitivity) algorithm was used to maximize the detection of randomized trials while excluding non-randomized research. The bibliographies of eligible publications were hand-searched to identify trials not identified in the electronic search.

PRINCIPAL FINDINGS

A total of 184 clinical trials were identified of which 163 were randomized controlled trials (RCTs). Of these clinical trials, 126 evaluated different drug regimens with 114 being RCTs. Only 21 clinical trials evaluated non-pharmacologic aspects of the RSI with 18 RCTs identified. A parallel search found 52 trials evaluating cricoid pressure (outside of the context of an RSI technique) with 44 classified as RCTs. Definitive outcomes such as prevention of aspiration and mortality benefit could not be evaluated from the trials. Likewise, the impact on adverse outcomes of the different components of RSI could not be ascertained.

CONCLUSION

An absence of evidence from RCTs suggests that the decision to use RSI during management can neither be supported nor discouraged on the basis of quality evidence.

Acid aspiration prophylaxis and caesarean section

Acid aspiration syndrome still contributes to the few anaesthesia-related deaths in caesarean section. Although none of the numerous measures intended to prevent such fatalities is based on clear evidence, many different regimens are being used. As obstetric acid aspiration syndrome occurs mainly in general anaesthesia, using regional techniques wherever possible may be the most effective prophylactic measure.

Crisis management during anaesthesia: regurgitation, vomiting, and aspiration

BACKGROUND

Regurgitation, vomiting and aspiration may occur unexpectedly in association with anaesthesia. "Aspiration/regurgitation" was ranked fifth in a large collection of previously reported incidents that arose during general anaesthesia. These problems are encountered by all practising anaesthetists and require instant recognition and a rapid, appropriate response. However, the diagnosis may not be immediately apparent as the initial presentation may vary from laryngospasm, desaturation, bronchospasm or hypoventilation to cardiac arrest.

OBJECTIVES

To examine the role of a previously described core algorithm "COVER ABCD-A SWIFT CHECK", supplemented by a specific sub-algorithm for regurgitation, vomiting and aspiration, in the management of these complications occurring in association with anaesthesia.

METHODS

The potential performance of this structured approach for each of the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS) was compared with the actual management as reported by the anaesthetists involved.

RESULTS

There were 183 relevant incidents of regurgitation, vomiting and aspiration among the first 4000 reports to the AIMS. Aspiration was documented in 96, was excluded in 69, and in 18 it could not be determined whether or not aspiration had occurred. It was considered that the correct use of an explicit algorithm would have led to earlier recognition and/or better management of the problem in 10% of all cases of regurgitation and vomiting and in 19% of those in which aspiration occurred.

CONCLUSION

Regurgitation and/or aspiration should always be considered immediately in any spontaneously breathing patient who suffers desaturation, laryngospasm, airway obstruction, bronchospasm, bradycardia, or cardiac arrest. Any patient in whom aspiration is suspected must be closely monitored in an appropriate perioperative facility, the acuity of which will depend on local staffing and workload. If clinical instability is likely to persist or if there are concerns by attending staff, the patient should be admitted to a high dependency unit or intensive care unit.

Management of pulmonary aspiration

Pulmonary aspiration of gastric contents in the perioperative phase is associated with increased postoperative morbidity and mortality. For the management of aspiration, differentiation between acid-associated aspiration pneumonitis and aspiration pneumonia as a consequence of a secondary bacterial contamination is of crucial importance. The incidence of aspiration in elective surgery is 1 per 2000-3000 anaesthesias in adults. In children, it is slightly more common with 1 per 1200-2600 anaesthesias. In the context of emergency anaesthesias the incidence of aspiration is three to four times higher. The risk particularly increases with recent ingestion of solid food or fluids, with older patients, with pregnant women, and with consciousness-reduced patients. Besides giving a review of the pathophysiology, incidence, and the risk factors of aspiration, this article places emphasis on the practical management of this anaesthesia-associated complication. Cricoid pressure, as a non-evidence-based but clinically wide-spread method in the context of the prophylaxis of aspiration, is discussed critically. The main part deals with strategies to structure the management of aspiration by use of scientific concepts based on medical crisis management. For this, an algorithm based on current scientific investigations is presented.

The incidence and outcome of perioperative pulmonary aspiration in a university hospital: a 4-year retrospective analysis

We evaluated the current incidence and outcome of perioperative pulmonary aspiration (PPA) in the nonobstetric adult population at a tertiary university medical center. A 4-yr retrospective analysis (January 2001-December 2004) was conducted using both quality improvement data and the hospital-wide medical archive recording system. PPA was defined as either detection of nonrespiratory secretions from the tracheobronchial tree or development of new pulmonary symptoms and/or new abnormalities in chest radiographs within 24 hr postoperatively. Of 99,441 anesthetics, 14 cases had confirmed PPA. Seven of them (50%) occurred in connection with gastroesophageal procedures. All patients had one or more predisposing risk factors for PPA. PPA occurred under general anesthesia in 10 patients and under monitored anesthesia care in 4 patients. In general anesthesia cases, the aspiration was recognized immediately after induction in 5 patients and occurred during changing of the endotracheal tubes in 5. The PPA was detected during the surgical procedures in all the monitored anesthesia care cases. Six patients with confirmed PPA developed pulmonary complications, of which, one died. Ten of 14 (70%) cases of PPA were the result of improper anesthesia technique. The current incidence of PPA is 1 of 7103, with morbidity 1 of 16,573 and mortality 1 of 99,441.

A review of patients with pulmonary aspiration of gastric contents during anesthesia reported to the Departmental Quality Assurance Committee

STUDY OBJECTIVE

Preoperative risk factors for pulmonary aspiration of gastric contents during anesthesia are well studied. There is lack of information as to factors or circumstances leading to aspiration.

DESIGN

A retrospective review of cases of pulmonary aspiration reported to the Departmental Quality Assurance (QA) Committee was undertaken.

SETTING

This study took place at a large tertiary care university hospital based in a metropolitan city.

PATIENTS

The study identified all patients reported to the QA Committee as having pulmonary aspiration during January 1991 to December 1994 and July 1996 to December 2000.

INTERVENTIONS

No interventions were done.

MEASUREMENTS

The medical records of all patients thus identified were reviewed to see if they had pulmonary aspiration according to strict criteria. Presence of preoperative known risk factors, prophylactic measures used against pulmonary aspiration, and perioperative events were noted.

MAIN RESULTS

A total of 47 patients were reported to the QA Committee as having pulmonary aspiration during this period. Upon review, 23 patients had pulmonary aspiration (definite aspiration, n = 12; probable aspiration, n = 11) and 24 patients did not meet the criteria for pulmonary aspiration of gastric contents. The incidence of pulmonary aspiration overall was 1 per 8671 anesthetics and 1 per 4385 anesthetics in patients younger than 16 years. If all 47 cases reported to QA Committee are presumed to have had pulmonary aspiration, then the overall incidence of aspiration is 1 in 4243 anesthetics. Eighteen of 23 patients had a preoperative risk factor, but preventive measures against aspiration had been used in only 4 patients. Five patients did not have any apparent preoperative risk factor.

CONCLUSIONS

This study confirms that pulmonary aspiration of gastric contents is a rare complication during modern anesthesia. Preoperative risk factor was present in most patients who had pulmonary aspiration. A clear understanding of risk factor/s is needed to prevent further cases of pulmonary aspiration.