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Systemic responses to tourniquet release in children
Insights
Deflating pneumatic tourniquets in children is generally safe, though longer inflation times or bilateral use can increase lactate. Controlled ventilation and timely blood gas monitoring can mitigate metabolic effects.
Area of Science:
- Pediatric Anesthesiology
- Surgical Hemodynamics
- Metabolic Effects of Tourniquets
Background:
- Pneumatic tourniquets are commonly used in pediatric surgery.
- Understanding the physiological impact of tourniquet release is crucial for patient safety.
- Limited data exists on the specific hemodynamic and metabolic responses in children.
Purpose of the Study:
- To evaluate the hemodynamic and metabolic effects of pneumatic tourniquet deflation in pediatric patients.
- To identify factors influencing adverse effects during tourniquet release.
- To provide recommendations for minimizing risks associated with tourniquet deflation in children.
Main Methods:
- Assessed 15 pediatric patients undergoing surgery with pneumatic tourniquets.
- Included seven patients with bilateral tourniquets.
- Monitored hemodynamic parameters (heart rate, blood pressure) and blood gas analysis (lactate, PaCO2, pH).
Main Results:
- Tourniquet deflation did not cause adverse effects in healthy children.
- Increased lactate levels were associated with longer tourniquet inflation times (>75 min) or bilateral tourniquets.
- The most significant pH decrease occurred with simultaneous bilateral tourniquet deflation.
- Systolic blood pressure decreased transiently (8-10 mm Hg) but returned to baseline within 5-10 minutes; no arrhythmias were observed.
Conclusions:
- Tourniquet deflation in children under general anesthesia is generally well-tolerated.
- Strategies to minimize metabolic disturbances include limiting inflation time (<75 min), utilizing controlled ventilation, and close post-deflation monitoring of blood gases.
- Specific monitoring is recommended for prolonged inflation times or simultaneous bilateral tourniquet release.
Abstract:
The hemodynamic and metabolic effects of deflation of pneumatic tourniquets were assessed in 15 children, seven of whom had bilateral tourniquets applied. Systemic acidosis from release of lactate and PaCO2 after tourniquet deflation did not cause adverse effects in these healthy children. Larger increases in lactate were seen with longer tourniquet inflation times (greater than 75 min) or with bilateral tourniquets. The greatest decrease in pH was seen with simultaneous deflation of bilateral tourniquets. Heart rate did not change with tourniquet deflation, whereas systolic blood pressure decreased 8-10 mm Hg with deflation. Blood pressure returned to control values within 5-10 min; no arrhythmias were seen. Recommendations to minimize the systemic metabolic effects after release of tourniquets in children under general anesthesia include the following: 1) attempt to limit tourniquet inflation times to less than 75 min; 2) use controlled ventilation prior to and after tourniquet deflation to remove the respiratory component of acidosis; 3) check blood gas tensions within 5 min of tourniquet deflation in children with long tourniquet inflation times (greater than 75 min), and where bilateral tourniquets are deflated simultaneously or within 30 min of each other.