Evaluation of hemodynamic changes with ultrasound cardiac output monitoring during burn wound excision and skin grafting in severely burned patients: a prospective observational study.

Objectives: To evaluate changes in hemodynamic parameters using the Ultrasound Cardiac Output Monitoring (USCOM) method during general anesthesia for burn wound excision and skin grafting surgery in patients with severe burns.

Methods: This prospective observational study included 40 severe burn patients, aged 18-60 years, treated at the Intensive Care Unit (ICU) of Le Huu Trac National Burn Hospital (Hanoi, Vietnam). All patients underwent burn wound excision and skin grafting between June 2023 and March 2024.

Results: The average heart rate (HR) at the study time points ranged from 116.8 to 124.3 beats/min. The differences in HR at T₁, T₂, T₃, T₅, and T₆ compared to T₀ were statistically significant (P < 0.05). Mean arterial pressure (MAP) at the study time points ranged from 73.8 mmHg to 95.68 mmHg. The differences in MAP at T₁, T₂, T₃, T₄, and T₅ compared to T₀ were statistically significant (P < 0.05). Cardiac Output (CO) and Cardiac Index (CI) values at all study time points were within normal ranges (6-7.04 l/min and 3.66-4.33 l/min/m², respectively). CO and CI were highest at T₀ (7.04 l/min; 4.33 l/min/m²) and lowest at T₁ (6 l/min; 3.66 l/min/m²). The differences in CO and CI at T₁, T₂, T₄, T₅, and T₆ compared to T₀ were statistically significant (P < 0.05). Stroke Volume (SV) and Stroke Volume Index (SVI) values at all time points were within normal ranges (51.2-56.75 ml and 30.93-34.53 ml/m²). The differences in SV and SVI at T₁, T₄, and T₅ compared to T₀ were statistically significant (P < 0.05). Systemic Vascular Resistance (SVR) and Systemic Vascular Resistance Index (SVRI) values at all time points were within normal ranges (1006.03-1240.45 d.s.cm^-5 and 1681.98-2060.4 d.s.cm^-5.m²). SVR and SVRI were highest at T₆ (1240.45 d.s.cm^-5 and 2060.4 d.s.cm^-5.m²) and lowest at T₁ (1006.03 d.s.cm^-5 and 1681.98 d.s.cm^-5.m²). The differences in SVR and SVRI at T₁ compared to T₀ were statistically significant (P < 0.05).

Conclusion: The study demonstrated that hemodynamic parameters, including CO, CI, SV, SVI, SVR, and SVRI, remained within normal ranges throughout the anesthesia process. However, heart rate and blood pressure tended to be elevated, reflecting the hemodynamic characteristics of burn patients. This underscores the importance of close monitoring and adaptive management during anesthesia and resuscitation to ensure hemodynamic stability tailored to the characteristics of severe burn patients.