Accuracy and precision of calibrated arterial pulse contour analysis in patients with subarachnoid hemorrhage requiring high-dose vasopressor therapy: a prospective observational clinical trial

Abstract

IntroductionCalibrated arterial pulse contour analysis has become an established method for the continuous monitoring of cardiac output (PCCO). However, data on its validity in hemodynamically instable patients beyond the setting of cardiac surgery are scarce. We performed the present study to assess the validity and precision of PCCO-measurements using the PiCCO™-device compared to transpulmonary thermodilution derived cardiac output (TPCO) as the reference technique in neurosurgical patients requiring high-dose vasopressor-therapy.MethodsA total of 20 patients (16 females and 4 males) were included in this prospective observational clinical trial. All of them suffered from subarachnoid hemorrhage (Hunt&Hess grade I-V) due to rupture of a cerebral arterial aneurysm and underwent high-dose vasopressor therapy for the prevention/treatment of delayed cerebral ischemia (DCI). Simultaneous CO measurements by bolus TPCO and PCCO were obtained at baseline as well as 2 h, 6 h, 12 h, 24 h, 48 h and 72 h after inclusion.ResultsPCCO- and TPCO-measurements were obtained at baseline as well as 2 h, 6 h, 12 h, 24 h, 48 h and 72 h after inclusion. Patients received vasoactive support with (mean ± standard deviation, SD) 0.57 ± 0.49 μg · kg-1 · min-1 norepinephrine resulting in a mean arterial pressure of 103 ± 13 mmHg and a systemic vascular resistance of 943 ± 248 dyn · s · cm-5. 136 CO-data pairs were analyzed. TPCO ranged from 5.2 to 14.3 l · min-1 (mean ± SD 8.5 ± 2.0 l · min-1) and PCCO ranged from 5.0 to 14.4 l · min-1 (mean ± SD 8.6 ± 2.0 l · min-1). Bias and limits of agreement (1.96 SD of the bias) were −0.03 ± 0.82 l · min-1 and 1.62 l · min-1, resulting in an overall percentage error of 18.8%. The precision of PCCO-measurements was 17.8%. Insufficient trending ability was indicated by concordance rates of 74% (exclusion zone of 15% (1.29 l · min-1)) and 67% (without exclusion zone), as well as by polar plot analysis.ConclusionsIn neurosurgical patients requiring extensive vasoactive support, CO values obtained by calibrated PCCO showed clinically and statistically acceptable agreement with TPCO-measurements, but the results from concordance and polar plot analysis indicate an unreliable trending ability.

Impact of transpulmonary thermodilution-based cardiac contractility and extravascular lung water measurements on clinical outcome of patients with Takotsubo cardiomyopathy after subarachnoid hemorrhage: a retrospective observational study

“…The findings of this two-center study should be validated by larger cohort trials. As use of catecholamines for the treatment of DCI in patients with TCM is still controversial [ 5 , 38 , 39 ], future studies should also be focused on establishing optimal methods of fluid management in these patients.…”

Validation of stroke volume and cardiac output by electrical interrogation of the brachial artery in normals: assessment of strengths, limitations, and sources of error

“…By mathematical coupling, this percent error is fully transferrable to the GEDV. Corroborating the aforementioned studies, data provided by Metzelder et al [ 35 ] show that, for a mean control ITBV of 1638 mL and a mean weight for patients of 74 kg, the mean calculated indexed ITBV was 22.14 mL kg −1 . When this value is divided by 1.25 to obtain GEDV, the result is 17.7 mL kg −1 .…”

“…However, this and our previous study [ 15 ], both showing proof of concept, serve as evidence that SV can be obtained by TBEV technique in the ideal homeostatic hemodynamic state. Future validation studies in sick humans, comparing TBEV to another validated continuous SV/CO technique, such as in the studies by Metzelder et al [ 35 ] and Lorne et al [ 44 ], will determine the viability of TBEV in clinical medicine.…”

Relationship between systolic blood pressures measured in emergency department and outcomes in patients with subarachnoid hemorrhage

“…It is possible that patients with higher BP in the ED might have had a higher rebleeding rate, contributing to the worse outcomes. However, few randomized trials to validate the current practice of lowering SBPs to ≤140–160 mmHg have been carried out to date, and it remains to be seen whether the threshold value of 189 mmHg observed in this study may have been influenced by the target SBP values, which may vary from institution to institution. Third, clinical outcomes were evaluated only at 30 days after symptom onset, and they might have been different if evaluated at a later time point.…”