Non-Invasive Bioimpedence Monitor Use in Obstetric Patients Undergoing Spinal Anesthesia for Cesearean Section

Research Article

Austin J Anesthesia and Analgesia.2014;1(1): 1001.

Non-Invasive Bioimpedence Monitor Use in Obstetric Patients Undergoing Spinal Anesthesia for Cesearean Section

Natesan Manimekalai, Izabela Wasiluk, Joana K. Panni, Igor Ianov, Moeen K. Panni*

Department of Anesthesiology, University of Florida, College of Medicine, Jacksonville, USA

*Corresponding author: Moeen K. Panni, Department of Anesthesiology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA.

Received: January 08, 2014; Accepted: January 10, 2014; Published: January 12, 2014

Abstract

Background: Hypotension during spinal anesthesia remains a common clinical issue, particularly during Cesarean sections and can lead to adverse maternal or neonatal outcomes. ASA standard monitoring of heart rate (HR) and blood pressure (BP) are common maternal variables monitored throughout C-sections as surrogate markers for maternal cardiac output (CO), which more directly reflects uteroplacental perfusion

Methods: Here we present the first description of bioreactancenon invasive cardiac monitor (NICOMTM) use in a series of healthy parturients undergoing elective Cesarean section under spinal anesthesia, a monitor that is now routinely used at our institution in the obstetric operating room.

Results: There was a very significant decrease in both SBP and DBP and increase in HR (p<0.001) after spinal anesthesia placement, however there was no significant change in the CO, CI or SVI (p>0.05) during that same period. This change was maximal at 1 and 2 minutes after spinal anesthesia respectively for HR and blood pressure. In contrast after delivery of the fetus there were no significant changes in SBP, DBP and HR (p>0.05), but a dramatic increase in CO (22.5%), CI (16.3%) as well as SVI (13.6%). There were no further changes to any of these parameters at delivery of the placenta; however there was maintenance of the elevated cardiac output and stroke volume index compared to the base line at the time of the spinal placement.

Conclusion: While transient maternal hypotension does not seem to result in adverse short term neonatal outcome, it would be ideal to maintain maternal cardiac output for both maternal and fetal reasons. Routine use of NICOM in all C-section patients should be considered, particularly in high risk obstetric patients where early intervention for developing hypotension and more importantly reduced cardiac output, is critical.

Keywords: NICOM, spinal anesthesia, cardiac output

Introduction

Hypotension during spinal anesthesia remains a common clinical issue, particularly during Cesarean sections (C-sections) [1]. If hypotension does not resolve promptly, maternal complications of nausea and vomiting are likely occur [2], and if this is persistent; more serious consequences may result; such as decreased consciousness, pulmonary aspiration and in extreme but rare instances maternal cardiac arrest can occur [3]. Prolonged periods of hypotension can also lead to reduced placental blood flow compromising the fetus [4].

Early signs of hypotensive episodes are important to recognize, so that adequate and prompt treatment with vasopressorsand/or intravenous fluid resuscitation occurs, whichever is appropriate [5]. ASA standard monitoring of heart rate (HR) and blood pressure (BP) are common maternal variables monitored throughout the operative procedure for C-sectionsand are used as surrogate markers for maternal cardiac output (CO), which more directly reflectsuteroplacental perfusion [1]. Direct measurement and monitoring of maternal cardiac output would be ideal in the management of parturients undergoing Cesarean section; however these monitoring choices involve invasive techniques. Recently new non-invasive methods of monitoring hemodynamic status have been developed and clinically validated [6, 7],whichalsocan provide other useful hemodynamic indicatorsin addition to cardiac output (CO), such as cardiac index (CI) and stroke volume index (SVI). To date NICOM has not been extensively used in the obstetric operating room, likely due in part to cost and equipment availability.

Here we present the first description of bioreactancenon invasive cardiac monitor (NICOMTM, Cheetah Medical Inc., Wilmington, Delaware, USA) use in a series of healthy parturientsundergoing elective Cesarean section under spinal anesthesia, a monitor that is now routinely used at our institution in the obstetric operating room.

Methods

Following Institutional Review Board (IRB) approval, a retrospective review of 13 randomly selected healthy parturients who had received spinal anesthesia for elective C- section was performed; patients that had also had a NICOMTM monitor placed (Figure 1) as well as other standard hemodynamic monitoring was maintained (NIBP, Pulse Ox and ECG) in addition to NICOMTM. Inclusion criteria for analysis; were pregnant patients undergoing elective C-section under spinal anesthesia that had full hemodynamic monitoring during the case, including use of NICOMTM. Exclusion criteria were patients that either did not undergo elective C-section with spinal anesthesia or did not have all the hemodynamic monitor information recorded during the C-section. Standard demographic data, such as age, height, weight, gestational age, IV fluid bolus, thespinal anesthesia regimen, and vasopressor use, such as epinephrine/ phenylepherinewas also collected from these cases.