Acute cardiac tamponade during atrial flutter ablation: improved hemodynamics after positive pressure ventilation: a case report.

INTRODUCTION: Acute cardiac tamponade is a rare event during any type of interventional or surgical procedure. It can occur during electrophysiology procedures due to radiofrequency ablation, lead or catheter manipulation, transseptal puncture, laser lead extractions, or left atrial appendage occlusion device positioning. Cardiac tamponade is difficult to study in a prospective manner, and case reports and case series are important contributions to understanding the best options for patient care. An 87-year-old Caucasian male patient breathing spontaneously developed acute tamponade during an atrial flutter ablation. Pericardial drain insertion was difficult, and hypotension failed to respond to epinephrine boluses. The patient became hypoxemic and hypercarbic, requiring intubation. Unexpectedly, the blood pressure markedly increased postintubation and remained in a normal range until the pericardium was drained. CONCLUSION: Spontaneous ventilation is considered important to maintain venous return to the right heart during cardiac tamponade. However, spontaneous ventilation reduces venous return to the left heart and worsens the paradoxical pulse in tamponade. Intravenous vasopressors are thought to be ineffective during cardiac tamponade. Our patient maintained pulmonary blood flow as indicated by end-tidal carbon dioxide measurements but had no measurable systemic blood pressure during spontaneous ventilation. Our case demonstrates that tracheal intubation and positive pressure ventilation can transiently improve left heart venous return, systemic perfusion, and drug delivery to the systemic circulation.

Near-Infrared Spectroscopy for Determination of Cardiac Output Augmentation in a Swine Model of Ischemia-Reperfusion Injury.

CONTEXT: Near infrared spectroscopy (NIRS) is a noninvasive tool for assessing local oxygen balance. In circulatory shock, the microcirculatory environment as measured by NIRS during resuscitation may provide additional diagnostic tools of value to the critical care physician. HYPOTHESIS: To assess whether a relative increase in peripheral NIRS was correlated with a clinically relevant increase in cardiac output following a fluid bolus in a swine model of shock. METHODS AND MODELS: Nine healthy young adult swine with median weight 80 kg (interquartile range, 75-83 kg) were anesthetized and surgically instrumented. They underwent a controlled hemorrhage of 20% of their blood volume followed by partial or complete aortic occlusion to create a variable ischemia-reperfusion injury. Next, the animals underwent four 500-mL plasmalyte boluses over 9 minutes each followed by a 6-minute pause. The animal then underwent a 25% mixed auto/homologous blood transfusion followed by four more 500 mL plasmalyte boluses over 9 minutes. Finally, the animals underwent a 25% mixed auto/homologous blood transfusion followed by an additional four rounds of 500-mL plasmalyte boluses over 9 minutes. Left thoracic limb NIRS, descending thoracic aortic flow (dAF), arterial blood pressure (MAP), central venous pressure (CVP), and mixed central venous oxygen saturation (Svo2) were measured continuously for comparison. RESULTS: The area under the receiver operating curve for an increase in dAF of 10% in response to a 500 mL bolus based on a percent increase in the proximal NIRS was 0.82 with 95% CI, 0.72-0.91; Svo2, 0.86 with 95% CI, 0.78-0.95; MAP, 0.75 with 95% CI, 0.65-0.85 and CVP, 0.64 with 95% CI, 0.53-0.76. INTERPRETATION AND CONCLUSIONS: A dynamic relative increase in NIRS in response to a crystalloid challenge has moderate discriminatory power for cardiac output augmentation during shock in a swine model of ischemia-reperfusion injury. NIRS performed as well as invasive measurements (Svo2 and MAP) and better than CVP.

Closed-loop automated critical care as proof-of-concept study for resuscitation in a swine model of ischemia-reperfusion injury.

BACKGROUND: Volume expansion and vasopressors for the treatment of shock is an intensive process that requires frequent assessments and adjustments. Strict blood pressure goals in multiple physiologic states of shock (traumatic brain injury, sepsis, and hemorrhagic) have been associated with improved outcomes. The availability of continuous physiologic data is amenable to closed-loop automated critical care to improve goal-directed resuscitation. METHODS: Five adult swine were anesthetized and subjected to a controlled 30% estimated total blood volume hemorrhage followed by 30 min of complete supra-celiac aortic occlusion and then autotransfusion back to euvolemia with removal of aortic balloon. The animals underwent closed-loop critical care for 255 min after removal of the endovascular aortic balloon. The closed-loop critical care algorithm used proximal aortic pressure and central venous pressure as physiologic input data. The algorithm had the option to provide programmatic control of pumps for titration of vasopressors and weight-based crystalloid boluses (5 ml/kg) to maintain a mean arterial pressure between 60 and 70 mmHg. RESULTS: During the 255 min of critical care the animals experienced hypotension (< 60 mmHg) 15.3% (interquartile range: 8.6-16.9%), hypertension (> 70 mmHg) 7.7% (interquartile range: 6.7-9.4%), and normotension (60-70 mmHg) 76.9% (interquartile range: 76.5-81.2%) of the time. Excluding the first 60 min of the critical care phase the animals experienced hypotension 1.0% (interquartile range: 0.5-6.7%) of the time. Median intervention rate was 8.47 interventions per hour (interquartile range: 7.8-9.2 interventions per hour). The proportion of interventions was 61.5% (interquartile range: 61.1-66.7%) weight-based crystalloid boluses and 38.5% (interquartile range: 33.3-38.9%) titration of vasopressors. CONCLUSION: This autonomous critical care platform uses critical care adjuncts in an ischemia-reperfusion injury model, utilizing goal-directed closed-loop critical care algorithm and device actuation. This description highlights the potential for this approach to deliver nuanced critical care in the ICU environment, thereby optimizing resuscitative efforts and expanding capabilities through cognitive offloading. Future efforts will focus on optimizing this platform through comparative studies of inputs, therapies, and comparison to manual critical care.

Endobronchial Intubation to Facilitate Extraluminal Bronchial Blocker Placement in Young Children: A Retrospective Case Series.

OBJECTIVES: Extraluminal bronchial blocker placement has become a well-accepted approach to one-lung ventilation in young children. In some cases, technical issues with placement may require alternative approaches to correct bronchial blocker positioning. The primary aim of this study was to review the authors' experience with using endobronchial intubation to facilitate extraluminal bronchial blocker placement in young children. DESIGN: Single-center case series of pediatric patients undergoing thoracic surgery and one-lung ventilation using a bronchial blocker. SETTING: Tertiary academic medical center. PARTICIPANTS: Pediatric patients < three years of age undergoing thoracic surgery and one-lung ventilation who underwent bronchial blocker placement using endobronchial intubation to facilitate blocker placement. In all patients, the bronchial blocker was inserted through a selectively mainstemmed endotracheal tube to facilitate blocker positioning. INTERVENTIONS: No interventions were performed. MEASUREMENTS AND MAIN RESULTS: Fifteen patients were identified after a query of the local electronic health record. There were five right-sided and ten left-sided placements in this cohort. Bronchial blocker placement was successful in 14 of 15 patients using endobronchial intubation to facilitate bronchial blocker placement. In one patient, the bronchial blocker was discovered in the nonsurgical bronchus, following placement with this technique. The bronchial blocker was repositioned manually into the desired mainstem bronchus prior to lateral positioning. CONCLUSIONS: Mainstem intubation can be used to facilitate bronchial blocker placement in young children and represents an alternative approach to extraluminal bronchial blocker placement.

It's Not Over Till It's Over: A Prospective Cohort Study and Analysis of "Anesthesia Stat!" Emergency Calls in the Pediatric Post-Anesthesia Care Unit (PACU).

Background Emergency "Anesthesia Stat!" (AS!) calls remain a common practice in medical centers even when advanced communication infrastructures are available. We hypothesize that the analysis of post-procedure "AS!" calls will lead to actionable insights which may enhance patient safety. Methods After institutional review board approval, we prospectively collected data from April 2015 through May 2018 on "AS!" calls throughout the pediatric operating rooms (OR), off-site locations, and post-anesthesia care unit (PACU) at a tertiary university medical center. Data recorded included demographic information, location, time of the event, event duration, vital signs, medications, anesthesia staff, attending anesthesiologist, and staff responding to the call. A narrative account of the event was also documented. Results A total of 82 "AS!" calls occurred, with ages ranging from 11 days old to 17 years old. Forty-nine of the 82 calls (60%) occurred at emergence. Seventy-one of the 82 calls (87%) were solely respiratory-related. Thirty-five of 49 emergence calls (71%) occurred in the PACU. Further, 34 of 35 PACU calls (97%) were respiratory-related, with 30 of 35 PACU calls (86%) associated with desaturation requiring intervention by anesthesia staff. Finally, 31 of 35 PACU calls (89%) occurred within 30 minutes of patient arrival to PACU. Conclusion Analysis of "AS!" events from our PACU continues to support the need for the prompt and continuous availability of at least one staff member with advanced airway management skills. Further, pediatric patients undergoing general anesthesia and surgery should likely be monitored for a minimum of 30 minutes following arrival in the PACU.

Hypoxemia in Young Children Undergoing One-lung Ventilation: A Retrospective Cohort Study.

BACKGROUND: One-lung ventilation in children remains a specialized practice with low case numbers even at tertiary centers, preventing an assessment of best practices. The authors hypothesized that certain case factors may be associated with a higher risk of intraprocedural hypoxemia in children undergoing thoracic surgery and one-lung ventilation. METHODS: The Multicenter Perioperative Outcomes database and a local quality improvement database were queried for documentation of one-lung ventilation in children 2 months to 3 yr of age inclusive between 2010 and 2020. Patients undergoing vascular or other cardiac procedures were excluded. All records were reviewed electronically for the presence of hypoxemia, oxygen saturation measured by pulse oximetry (Spo2) less than 90% for 3 min or more continuously, and severe hypoxemia, Spo2 less than 90% for 5 min or more continuously during one-lung ventilation. Records were also assessed for hypercarbia, end-tidal CO2 greater than 60 mmHg for 5 min or more or a Paco2 greater than 60 on arterial blood gas. Covariates assessed for association with these outcomes included age, weight, American Society of Anesthesiologists (Schaumburg, Illinois) Physical Status 3 or greater, duration of one-lung ventilation, preoperative Spo2 less than 98%, bronchial blocker versus endobronchial intubation, left operative side, video-assisted thoracoscopic surgery, lower tidal volume ventilation (tidal volume less than or equal to 6 ml/kg plus positive end expiratory pressure greater than or equal to 4 cm H2O for more than 80% of the duration of one-lung ventilation), and type of procedure. RESULTS: Three hundred six cases from 15 institutions were included for analysis. Hypoxemia and severe hypoxemia occurred in 81 of 306 (26%) patients and 56 of 306 (18%), respectively. Hypercarbia occurred in 153 of 306 (50%). Factors associated with lower risk of hypoxemia in multivariable analysis included left operative side (odds ratio, 0.45 [95% CI, 0.251 to 0.78]) and bronchial blocker use (odds ratio, 0.351 [95% CI, 0.177 to 0.67]). Additionally, use of a bronchial blocker was associated with a reduced risk of severe hypoxemia (odds ratio, 0.290 [95% CI, 0.125 to 0.62]). CONCLUSIONS: Use of a bronchial blocker was associated with a lower risk of hypoxemia in young children undergoing one-lung ventilation.

Bronchial Blocker Entrapment in a 7-Month-Old Infant: A Case Report.

We present the case of a 7-month-old infant undergoing thoracotomy and left lower lobe lobectomy who experienced a significant complication related to lung isolation with a bronchial blocker. Despite good isolation and seemingly appropriate positioning, the bronchial blocker became entrapped within the staple line at the bronchial stump. Fortunately, the surgeon was able to free the blocker. Going forward, we recommend clinicians be vigilant in positioning the blocker just distal to the carina in all cases and, further, consider retracting the blocker into the trachea before surgical intervention on the airway to avoid inadvertent entrapment of the device.

Experience with a "Feed and Swaddle" program in infants up to six months of age.

BACKGROUND: Feed and swaddle is a technique in which an infant is fed and allowed to fall asleep to facilitate diagnostic imaging. This study reviews our experience and diagnostic success in premature and term infants up to 6 months old undergoing brain magnetic resonance imaging (MRI) using a feed and swaddle technique and with comparable patients imaged under anesthesia. METHODS: We reviewed the charts of all infants ≤6 months who underwent brain MRI at our institution between 1 January 2013 and 31 March 2016. We recorded and analyzed demographic information, scan indication, scan length, prematurity status, anesthetic technique if used, complications, and diagnostic success or failure. RESULTS: One hundred and sixty-four term infants underwent brain MRI using a feed and swaddle technique. The success rate in term infants <90 days was 91.1% (113/124) versus 95.0% (38/40) in infants ≥90 days and ≤181 days old. Fifty-three premature infants underwent feed and swaddle for brain MRI with a diagnostic success rate of 92.5% (49/53). No complications were noted in any feed and swaddle patients. Those who received anesthesia had a diagnostic success rate of 100% (70/70) but experienced complications including hypoxemia, 14.3% (10/70); hypothermia, 18.9% (10/53); bradycardia, 10.1% (7/69); and hypotension, 4.2% (3/70). CONCLUSION: Given the high rate of success and absence of complications with feed and swaddle in children ≤6 months for brain MRI and the presence of anesthesia-related complications, most infants should undergo a trial of feed and swaddle prior to undergoing brain MRI with anesthesia.

Assessment of Common Criteria for Awake Extubation in Infants and Young Children.

BACKGROUND: Practice patterns surrounding awake extubation of pediatric surgical patients remain largely undocumented. This study assessed the value of commonly used predictors of fitness for extubation to determine which were most salient in predicting successful extubation following emergence from general anesthesia with a volatile anesthetic in young children. METHODS: This prospective, observational study was performed in 600 children from 0 to 7 yr of age. The presence or absence of nine commonly used extubation criteria in children were recorded at the time of extubation including: facial grimace, eye opening, low end-tidal anesthetic concentration, spontaneous tidal volume greater than 5 ml/kg, conjugate gaze, purposeful movement, movement other than coughing, laryngeal stimulation test, and oxygen saturation. Extubations were graded as Successful, Intervention Required, or Major Intervention Required using a standard set of criteria. The Intervention Required and Major Intervention Required outcomes were combined as a single outcome for analysis of predictors of success. RESULTS: Successful extubation occurred in 92.7% (556 of 600) of cases. Facial grimace odds ratio, 1.93 (95% CI, 1.03 to 3.60; P = 0.039), purposeful movement odds ratio, 2.42 (95% CI, 1.14 to 5.12; P = 0.022), conjugate gaze odds ratio, 2.10 (95% CI, 1.14 to 4.01; P = 0.031), eye opening odds ratio, 4.44 (95% CI, 1.06 to 18.64; P= 0.042), and tidal volume greater than 5 ml/kg odds ratio, 2.66 (95% CI, 1.21 to 5.86; P = 0.015) were univariately associated with the Successful group. A stepwise increase in any one, in any order, of these five predictors being present, from one out of five and up to five out of five yielded an increasing positive predictive value for successful extubation of 88.3% (95% CI, 82.4 to 94.3), 88.4% (95% CI, 83.5 to 93.3), 96.3% (95% CI, 93.4 to 99.2), 97.4% (95% CI, 94.4 to 100), and 100% (95% CI, 90 to 100). CONCLUSIONS: Conjugate gaze, facial grimace, eye opening, purposeful movement, and tidal volume greater than 5 ml/kg were each individually associated with extubation success in pediatric surgical patients after volatile anesthetic. Further, the use of a multifactorial approach using these predictors, may lead to a more rational and robust approach to successful awake extubation.

A generalized multistage approach to oral and nasal intubation in infants with Pierre Robin sequence: A retrospective review.

BACKGROUND: Airway management in children with Pierre Robin sequence in the infantile period can be challenging and frequently requires specialized approaches. AIMS: The aim of this study was to review our experience with a multistage approach to oral and nasal intubation in young infants with Pierre Robin sequence. METHODS: After IRB approval, we reviewed 13 infants with Pierre Robin sequence who underwent a multistage approach to intubation in the operating room for mandibular distractor or gastrostomy tube placement. All patients underwent awake placement of either an LMA-Classic™ #1 or ProSeal™ laryngeal mask airway size #1. General anesthesia was induced with sevoflurane, and patients were relaxed with rocuronium. The laryngeal mask airway was replaced with an air-Q® 1.0. Children were then intubated through the air-Q® 1.0 using a flexible fiberoptic bronchoscope. In cases that required a nasotracheal tube, the oral tube was left in place while a flexible fiberoptic bronchoscope loaded with a similar internal diameter nasal Ring-Adair-Elwyn (RAE) tube was introduced into the nares. Once the scope was in proximity to the glottis, the oral tube was removed and the patient was intubated with the nasal RAE over the fiberscope. RESULTS: All 13 patients with Pierre Robin sequence were successfully intubated. We observed no periods of desaturation during placement and induction with the LMA-Classic™ or ProSeal™ laryngeal mask airway except in one patient who was in extremis in the neonatal intensive care unit and required emergent transport to the operating room with the laryngeal mask airway in place. We observed several brief periods of desaturation during the apneas associated with fiberoptic intubation. CONCLUSION: In conclusion, we were able to use a ventilation-driven, multistaged approach using the unique properties of different supraglottic airways to facilitate oral and nasal intubation in 13 infants with Pierre Robin sequence.

Nitroglycerin: An unusual solution to intraoperative hypothermia in a 4-year-old burn patient.

We describe the case of a 4-year-old child undergoing extensive burn surgery with refractory intraoperative hypothermia. A low-dose nitroglycerin infusion was initiated to reverse vasoconstriction and improve heat absorption, after which the child's temperature steadily improved. In hypothermic burn patients, topical vasoconstrictors may hinder surface warming efforts. A vasodilator infusion may aid in warming the pediatric patient undergoing extensive excision and grafting.

A Prospective Comparison of Intraluminal and Extraluminal Placement of the 9-French Arndt Bronchial Blocker in Adult Thoracic Surgery Patients.

OBJECTIVE: To compare the standard intraluminal approach with the placement of the 9-French Arndt endobronchial blocker with an extraluminal approach by measuring the time to positioning and other relevant intraoperative and postoperative parameters. DESIGN: A prospective, randomized, controlled trial. SETTING: University hospital. PARTICIPANTS: The study comprised 41 patients (20 intraluminal, 21 extraluminal) undergoing thoracic surgery. INTERVENTION: Placement of a 9-French Arndt bronchial blocker either intraluminally or extraluminally. Comparisons between the 2 groups included the following: (1) time for initial placement, (2) quality of isolation at 1-hour intervals during one-lung ventilation, (3) number of repositionings during one-lung ventilation, and (4) presence or absence of a sore throat on postoperative days 1 and 2 and, if present, its severity. MEASUREMENTS AND MAIN RESULTS: Median time to placement (min:sec) in the extraluminal group was statistically faster at 2:42 compared with 6:24 in the intraluminal group (p < 0.05). Overall quality of isolation was similar between groups, even though a significant number of blockers in both groups required repositioning (extraluminal 47%, intraluminal 40%, p > 0.05), and 1 blocker ultimately had to be replaced intraoperatively. No differences in the incidence or severity of sore throat postoperatively were observed. CONCLUSIONS: A statistically significant reduction in time to placement using the extraluminal approach without any differences in the rate of postoperative sore throat was observed. Whether placed intraluminally or extraluminally, a significant percentage of Arndt endobronchial blockers required at least one intraoperative repositioning.