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High-intensity transient signals during laparoscopic surgery in children
P Schramm1, K Engelhard, A Scherhag
1Department of Anaesthesiology, University Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany. schrammp@uni-mainz.de
Insights
Pneumoperitoneum during laparoscopic surgery in children can increase the occurrence of high-intensity transient signals (HITS), a marker of potential cerebral emboli. This study monitored HITS before and after pneumoperitoneum to assess its impact on pediatric patients.
Area of Science:
- Pediatric Anesthesiology
- Minimally Invasive Surgery
- Cerebrovascular Physiology
Background:
- Laparoscopic surgery is increasingly common in pediatric patients.
- Pneumoperitoneum, used in laparoscopic procedures, may lead to gas emboli.
- The association between pneumoperitoneum and cerebral embolic events in children is not well-established.
Purpose of the Study:
- To investigate if pneumoperitoneum induces cerebral emboli in pediatric surgical patients.
- To assess the number and intensity of high-intensity transient signals (HITS) before and after pneumoperitoneum.
Main Methods:
- Twenty children undergoing laparoscopic surgery were monitored.
- Transcranial Doppler ultrasonography was used to detect HITS.
- Measurements of HITS, cerebral blood flow velocity, and mean arterial pressure (MAP) were taken during baseline anesthesia and during pneumoperitoneum (1.6-2.0 kPa CO2).
Main Results:
- High-intensity transient signals (HITS) were detected in 70% of patients during baseline and pneumoperitoneum.
- An additional 15% of patients developed HITS only during pneumoperitoneum.
- Mean arterial pressure (MAP) and cerebral blood flow velocity increased with pneumoperitoneum.
Conclusions:
- High-intensity transient signals (HITS) are present in a significant portion of pediatric surgical patients even before interventions.
- Pneumoperitoneum was found to further increase the occurrence of HITS in this pediatric cohort.
- Findings suggest a potential link between pneumoperitoneum and cerebral embolic signals in children.
Background:
Laparoscopic interventions in children gain increasing popularity. Pneumoperitoneum as applied during laparoscopic surgery can induce gas emboli formation, but it is unclear whether this is associated with cerebral embolic events. To investigate the hypothesis that pneumoperitoneum causes cerebral emboli in children, the number and intensity of high-intensity transient signals (HITS) detected using transcranial Doppler ultrasonography were assessed before and after induction of pneumoperitoneum.
Methods:
Twenty children were monitored during laparoscopic surgery. General anaesthesia was performed using sevoflurane and sufentanil or alfentanil. Pressure-controlled ventilation was adapted to maintain end-tidal Pco(2) (Pe'(co(2))) between 4.7 and 6.0 kPa. Baseline measurement of HITS rate, cerebral blood flow velocity, and mean arterial pressure (MAP) were recorded during steady-state anaesthesia before skin incision and during pneumoperitoneum with intra-abdominal pressure of 1.6-2.0 kPa applied using CO(2).
Results:
In 14 children (70%), HITS were detected during baseline and pneumoperitoneum. Three additional children (15%) developed HITS during pneumoperitoneum only and another three children (15%) presented no HITS during the investigation period. MAP and cerebral blood flow velocity increased with pneumoperitoneum.
Conclusions:
HITS are present in 70% of paediatric surgical patients under balanced anaesthesia before surgical interventions. Pneumoperitoneum further increased the occurrence of HITS.
