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Background

A light breakfast has been found to empty from the stomach within 4 hours in healthy volunteers.

Aim

The aim of this study was to investigate whether a light breakfast of yoghurt or gruel empties from the stomach within 4 hours, in children scheduled for general anaesthesia.

Method

In this observational cohort study, children aged 1‐6 years scheduled for elective general anaesthesia were prescribed free intake of yoghurt or gruel 4 hours prior to induction. They were subsequently examined with gastric ultrasound within 4 hours of ingestion. In case of gastric contents, the gastric antral area was measured, and gastric content volume (GCV) was calculated.

Results

Twenty children were included in the study and the ingested amount of gruel or yoghurt ranged 2.5‐25 mL kg⁻¹. In 15 cases, the stomach was empty with juxtaposed walls and no further measurements were made. In four cases, there was fluid present in the stomach, but the calculated gastric contents were <0.5 mL kg⁻¹. One patient had solids in the stomach, and GCV in this patient was calculated to 2.1 mL kg⁻¹. The patient with solids present had ingested 25 mL kg⁻¹ of gruel 4 hours prior to assessment. The planned procedure was therefore delayed 1 hour. There were no cases of pulmonary aspiration or vomiting.

Conclusion

A light breakfast 4 hours prior to induction may be considered, but there is need for further studies on safe limits for the volume ingested.

Background

Children often starve for longer than recommended by current preoperative fasting guidelines.

Aims

We studied the effects of implementing a more lenient fasting regimen on the duration of clear fluid fasting, as well as the incidence of extended fasting in children.

Methods

Preoperative duration of clear fluid fasting was recorded for patients scheduled for procedures in a unit applying the standard 6-4-2 fasting regimen. This group was compared with a cohort in the same unit 1year after transitioning to a 6-4-0 fasting regimen. The latter includes no limitations on clear fluid intake until the child is called to theater. A third cohort from a unit in which the 6-4-0 fasting regimen has been implemented for over a decade was also studied for comparison.

Results

Patients fasting according to the 6-4-2 fasting regimen (n=66) had a median fasting time for clear fluids of 4.0h and a 33.3% incidence of fasting more than 6h. After transitioning to the 6-4-0 fasting regimen (n=64), median duration of fasting for clear fluids decreased to 1.0h, and the incidence of fasting more than 6h decreased to 6.3%. In the second unit (n=73), median fasting time was 2.2h and the proportion of patients fasting more than 6h was 21.9%.

Conclusion

The introduction and implementation of the 6-4-0 fasting regimen reduces median fluid fasting duration and the number of children subjected to extended fasting.

BACKGROUND: International guidelines recommend 2 h of clear fluid fasting prior to general anesthesia. The pediatric anesthesia unit of Uppsala University Hospital has been implementing a more liberal fasting regime for more than a decade; thus, children scheduled for elective procedures are allowed to drink clear fluids until called to the operating suite.

AIM: To determine the incidence of perioperative pulmonary aspiration in pediatric patients allowed unlimited intake of clear fluids prior to general anesthesia.

METHOD: Elective pediatric procedures between January 2008 and December 2013 were examined retrospectively by reviewing anesthesia charts and discharge notes in the electronic medical record system. All notes from the care event and available chest x-rays were examined for cases showing vomiting, regurgitation, and/or aspiration. Pulmonary aspiration was defined as radiological findings consistent with aspiration and/or postoperative symptoms of respiratory distress after vomiting during anesthesia.

RESULTS: Of the 10 015 pediatric anesthetics included, aspiration occurred in three (0.03% or 3 in 10 000) cases. No case required cancellation of the surgical procedure, intensive care or ventilation support, and no deaths attributable to aspiration were found. Pulmonary aspiration was suspected, but not confirmed by radiology or continuing symptoms, in an additional 14 cases.

CONCLUSION: Shortened fasting times may improve the perioperative experience for parents and children with a low risk of aspiration.

Four basic types of visual aids are used for teaching airway management and decision-making in simulated as well as in real clinical situations: universal algorithms, sets of limited algorithms, concept-based cognitive aids, and checklists. The first three may represent an evolution in the understanding of the role of human error in both successful and failed airway management. Complex visual aids such as the American Society of Anesthesiology difficult airway algorithm may be more useful for teaching, while graphic cognitive aids like the Vortex may be more helpful for decision-making under stress. Not surprisingly, there is a lack of outcome studies, although some cognitive aids have been evaluated in simulation settings.

Objectives: 

To evaluate aeration/ventilation in saline-lavaged piglets during a 3-h follow-up after a recruitment maneuver (RM)/PEEP titration compared with PEEP 10 cmH₂O without a RM.

Background: 

Lung recruitment and PEEP titration are used to find a PEEP preventing repetitive opening/collapsing of lung.

Methods: 

Twenty-one lung-lavaged piglets, mean age 7 weeks and mean weight 10 kg; a RM-group and a PEEP10-group, were ventilated at PEEP 5 cmH₂O (baseline) followed by zero PEEP ventilation. In the RM-group, tidal elimination of CO₂ and dynamic compliance (Cdyn) guided recruitment and PEEP titration, respectively. A final 3-h ventilation followed using PEEP 2 cmH₂O above the first decline of Cdyn and end-inspiratory pressure (EIP) for a target tidal volume (V_T) of 10 ml·kg⁻¹. In the PEEP10-group, PEEP 10 cmH₂O without a RM was used during the final 3-h ventilation. CT scans and blood gases were repeated every 30 min. Airway pressures, Cdyn and hemodynamics were continuously recorded.

Results: 

Aeration improved without differences between groups. The RM-group PEEP level of 10 ± 0.6 cmH₂O did not differ from the PEEP10-group. Compared to baseline EIP was lower in the RM-group after 3-h ventilation. In both groups, driving pressure (DP) was lower and Cdyn higher than baseline. In the RM-group, final EIP and DP were lower and Cdyn higher than in the PEEP10-group.

Conclusions: 

Both RM/PEEP titration and PEEP elevation resulted in improved aeration without differences between groups at the end point. Lung aeration was achieved at lower EIP and DP and higher Cdyn in the RM-group than in the PEEP10-group.

Background To reduce risk for intermittent hypoxia a high fraction of inspired oxygen is routinely used during anesthesia induction. This differs from the cautious dosing of oxygen during neonatal resuscitation and intensive care and may result in significant hyperoxia. Aim In a randomized controlled trial, we evaluated oxygenation during general anesthesia with a low (23%) vs a high (80% during induction and recovery, and 40% during maintenance) fraction of inspired oxygen, in newborn infants undergoing surgery. Method Thirty-five newborn infants with postconceptional age of 35-44 weeks were included (17 infants in low and 18 in high oxygen group). Oxygenation was monitored by transcutaneous partial pressure of oxygen, pulse oximetry, and cerebral oxygenation. Predefined SpO2 safety targets dictated when to increase inspired oxygen. Results At start of anesthesia, oxygenation was similar in both groups. Throughout anesthesia, the high oxygen group displayed significant hyperoxia with higher (difference-20.3 kPa, 95% confidence interval (CI)-28.4 to 12.2, p < .001) transcutaneous partial pressure of oxygen values than the low oxygen group. While SpO2 in the low oxygen group was lower (difference - 5.8%, 95% CI -9.3 to -2.4, p < .001) during anesthesia, none of the infants spent enough time below SpO(2) safety targets to mandate supplemental oxygen, and cerebral oxygenation was within the normal range and not statistically different between the groups. Analysis of the oxidative stress biomarker urinary F-2-Isoprostane revealed no differences between the low and high oxygen group. Conclusion We conclude that in healthy newborn infants, use of low oxygen during general anesthesia was feasible, while the prevailing practice of using high levels of inspired oxygen resulted in significant hyperoxia. The trade-off between careful dosing of oxygen and risks of hypo- and hyperoxia in neonatal anesthesia should be further examined.

Background

Endtidal (ET) measurement of carbon dioxide is well established for intraoperative respiratory monitoring of adults and children, but the method's accuracy for intraoperative use in small newborn infants has been less extensively investigated.

Aims

The aim of this study was to compare carbon dioxide from ET measurements with arterialized capillary blood samples in newborn infants during general anesthesia and surgery.

Methods

Endtidal carbon dioxide was continuously measured during anesthesia and surgery and compared with simultaneous blood gas analyses obtained from capillary blood samples. Fifty-nine sample sets of ET to blood gas carbon dioxide were obtained from 23 prospectively enrolled infants with a gestational age of 23-41 weeks and a birth weight of 670-4110 g.

Results

Endtidal levels of carbon dioxide were considerably lower in all sample sets and only 4/23 individual ET-blood gas sample pairs differed <7.5 mm Hg (1 kPa). Bland-Altman analysis indicated a poor agreement with a bias of -13 7 mm Hg and a precision of +/- 14 mm Hg. The performance of ET measurements was particularly poor in infants weighing below 2.5 kg, in infants in need of respiratory support prior to anesthesia, and when the true (blood gas) carbon dioxide level was high, above 45 mm Hg.

Conclusion

Main-stream capnography during anesthesia and surgery correlated poorly to blood gas values in small and/or respiratory compromised infants. We conclude that caution should be exercised when relying solely on ET measurements to guide mechanical ventilation in the OR.

BACKGROUND: The COVID-19 pandemic is pushing healthcare systems to their limits. Dramatic reductions in the adult elective surgery are ubiquitous, but corresponding changes in pediatric services are not well described. The Swedish Perioperative Registry contains data on all anesthetic procedures in Sweden, and therefore, provides a unique opportunity to analyze the effect of the pandemic on the pediatric anesthesia capacity on a national level. We hypothesized that there would be a significant reduction in pediatric elective procedures. The aim was to determine the effects on pediatric surgical and anesthetic services during the first wave of the COVID-19 pandemic in Sweden.

METHODS: For this retrospective registry cohort study, we extracted all procedures performed on patients <18 years of age in 2020 and 2019. Weeks 12 to 26 of 2020 were defined as the first wave, and data were analyzed according to level of care, type of surgery, procedure code, and emergency or elective surgery.

RESULTS: We found 7015 fewer procedures during the first wave epoch. Elective cases were reduced by 53.7% while emergency surgery was not significantly affected. During the peak of the first wave in April, there was a 72.8% reduction in elective cases; ENT/maxillofacial surgery showed the greatest reduction (86.7%). The surgical and anesthesia capacity recovered to near-normal levels by the end of June 2020.

CONCLUSION: We conclude that the impact of COVID-19 on pediatric surgical procedures in Sweden during the first wave of the pandemic was dramatic, but elective services were restored a few months after the peak.

Background: Surgical correction for craniosynostosis is often associated with significant perioperative hemorrhage. We implemented a transfusion strategy with a strict protocol including transfusion triggers, frequent assessment of coagulation tests, and the use of a novel transfusion unit, the mixed pediatric unit. Aim: The aim of the study was to evaluate if the applied transfusion strategy could reduce total blood loss and number of blood donors. Methods: Children <1 year old admitted for craniosynostosis surgery were included for the study. On the day before surgery, an adult red blood cell unit was mixed with plasma and split into two mixed pediatric units-one intended for intraoperative use and the other saved for the postoperative period. A series of blood samples were obtained for standard coagulation parameters as well as thromboelastography to evaluate potential coagulopathy. Estimated blood loss, the number of additional standard packed red cell units opened in the first 24 h after surgery, the volume of fluid administered, and the total transfusion volumes were compared to a historical control group with similar age and characteristics. Results: Nineteen infants were included in the study group, and were compared to 21 historical controls. There was a significant reduction of intraoperative transfusion volume. Twelve patients were transfused postoperatively, but in 8 of these additional exposure to packed red cell donor blood was avoided by using the saved mixed pediatric unit. In the historical controls, a total of 10 packed red cell units were used in nine patients postoperatively. No additional transfusions of plasma, platelets, fibrinogen, or tranexamic acid were needed in either group, and the coagulation parameters including thromboelastography remained within their respective normal ranges in the study group. Conclusion: For craniofacial surgery in infants, moderate perioperative blood loss and avoidance of coagulopathy is possible when a multifactorial approach is implemented. In this setting, intraoperative, but not total perioperative blood loss was reduced with the studied protocol. The study indicates that there may be a role for mixed pediatric units to reduce exposure to multiple donors although the reduction in total donor exposure was not significant.

Background

A new software has recently been incorporated in almost all new anesthesia machines to enable automatic lung recruitment maneuvers. To date, no studies have assessed the safety and efficacy of these automatic software programs in the neonatal population.

Aims

We aimed to evaluate the safety and efficacy of the lung recruitment maneuver performed using the automatic stepwise recruitment maneuver software of the FLOW-i 4.3 Anesthesia System^® in a healthy and live neonatal model.

Methods

Eight male newborn piglets were included in the study. The lung recruitment maneuver was performed in pressure-controlled ventilation with a constant driving pressure (15 cmH₂O) in a stepwise increasing positive end-expiratory pressure (PEEP) model. The target peak inspiratory pressure (PIP) was 30 cmH₂O and PEEP was 15 cmH₂O. The maneuver lasted for 39 seconds. The hemodynamic variables were monitored using the PICCO^® system. The following respiratory parameters were monitored: oxygen saturation, fraction of inspired oxygen, partial pressure of oxygen and carbon dioxide in the arterial blood, end-tidal carbon dioxide pressure, PIP, plateau pressure, PEEP, static compliance (C_stat), and dynamic compliance (C_dyn).

Safety was evaluated by assessing the accuracy of the software, need for not interrupting the maneuver, hemodynamic stability, and absence of adverse respiratory events with the lung recruitment maneuver. Efficacy was evaluated by improvement in C_stat and C_dyn after performing the lung recruitment maneuver.

Results

All lung recruitment maneuvers were safely performed as scheduled without any interruptions. No pneumothorax or other side effects were observed. Hemodynamic stability was maintained during the lung recruitment maneuver. We observed an improvement of 33% in C_dyn and 24% in C_stat after the maneuver.

Conclusions

The automatic stepwise recruitment maneuver software of the FLOW-i 4.3 Anesthesia System^® is safe and efficacious in a healthy neonatal model. We did not observe any adverse respiratory or hemodynamic events during the implementation of the lung recruitment maneuver in the pressure-controlled ventilation mode using a stepwise increasing PEEP (30/15 cmH₂O) approach.

Background: Diclofenac is an effective, opiate-sparing analgesic for acute pain in children, which is commonly used in pediatric surgical units. Recently, a Cochrane review concluded the major knowledge gap in diclofenac use is dosing information. A pharmacokinetic meta-analysis has been undertaken with the aim of recommending a dose for children aged 1-12 years. Methods: Studies containing diclofenac pharmacokinetic data were identified during a Cochrane systematic review, and authors were asked to provide raw data. A pooled population analysis was undertaken in NONMEM to define the pharmacokinetics of intravenous, oral, and rectal diclofenac in children. Simulations were performed to recommend a dose yielding an equivalent area under diclofenac concentration-time curve (AUC) to a 50-mg dispersible tablet in adults. Results: Data from 111 children aged 1-14 years consisting of 375 samples following intravenous, oral suspension, and suppositories were used. Adult dispersible tablet and suspension data were added to provide a reference AUC and support the absorption modeling, respectively. A three-compartment model described disposition, a dual-absorption compartment model was used for suspension and dispersible tablet data, and single-absorption compartment model for suppositories. The estimate of clearance was 16.51.h(-1).70 kg(-1) and bioavailabilities were 0.36, 0.63, and 0.35 for suspension, suppository, and dispersible tablets, respectively. Conclusions: Single doses of 0.3 mg.kg(-1) for intravenous, 0.5 mg.kg(-1) for suppositories, and 1 mg.kg(-1) for oral diclofenac in children aged 1 12 years are recommended as they yield a similar AUC to 50 mg in adults.

Background: Noninvasive measurements of hemoglobin in the pediatric perioperative setting could be helpful to avoid venipunctures in children. The present study aims to evaluate this by using a noninvasive device for hemoglobin determination. We compared noninvasively obtained hemoglobin with laboratory hemoglobin concentrations in children during their preoperative assessment.

Methods: In an observational study, 122 nonanemic children (age 4.21.6years) who were scheduled to undergo different surgical procedures under general anesthesia were included. In their preoperative preparations, single invasive blood samples for laboratory hemoglobin concentrations were routinely taken following hospital policy and compared to simultaneous noninvasive determinations of hemoglobin. A preoperative invasive value 9g/dL would have caused cancelation of surgery and implied further investigations.

Results: A Bland-Altman plot showed that the average difference between noninvasively obtained hemoglobin and laboratory hemoglobin concentration was -0.44g/dL (bias) with a standard deviation of the mean bias of 1.04g/dL. A hemoglobin error grid showed that the noninvasive device could identify almost all invasive hemoglobin values >9g/dL. In total, there were 4 false-positive values where noninvasively obtained hemoglobin observations were below while the paired invasive values were above 9g/dL.

Conclusion: The data in this pediatric setting suggest that the device may eliminate the need for venipuncture in nonanemic children.