PREOPERATIVE OPTIMIZATION OF THE VOLEMIC STATUS IN PATIENTS WITH OBESITY

Vorotyntsev S. І.

CLINICAL AND EXPERIMENTAL MEDICINE

Scentific article

Obesity is a risk factor for many perioperatve complicatons, cardiovascular in partcular, that most ofen occur when hemodynamics is unstable. It is proved that hypotension occurs more ofen in patents with obesity during inducton of anaesthesia. This is due to inital hypovolemia in 70% of patents with morbid obesity who are preparing for bariatric surgery with help of the program for weight loss. But publicatons related to the regime of fluid therapy for non-bariatric patents with increased BMI, especially with a focus on preoperatve treatment, are few and not based on general consensus. The aim of our work was to evaluate the effect of preoperatve individualized according to the ideal body weight (IBW) volume loading by fluid (VL) on hemodynamic parameters and to determine the incidence of preoperatve hypotension (POH) during the use of VL in obese patents. The research included 26 obese patents (BMI>30 kg/m2) that were planned for scheduled laparoscopic surgery and to whom the dynamics of the stroke volume of the heart (SV) and the index of systemic vascular resistance (SVRI) were measured using impedance measurement afer VL by balanced colloid (Gelaspan, BBraun, Germany) at a rate of 6 ml/kg IBW in additon to standard monitoring of hemoglobin saturaton (SpO2), noninvasive mean arterial pressure (MAP) and heart rate (HR). The research was conducted in awake patents immediately before the inducton of anesthesia. They were classifed as volume-respondents if SV increased by more than 13% from the inital level. Afer inducton of anesthesia (diazepame 1.25-2.5 mg, fentanyl 1-1.5 mg/kg IBW, atracurium 0.4 mg/kg LBW (lean body weight), propofol 1-2 mg/kg of LBW, ketamine 0.15 mg/kg IBW) but before the operaton any decrease of BP by more than 20% from the basic level was considered as hypotension. The incidence of POH and the mean level of MAP were compared with retrospectve data in a group of obese patents to whom VL by colloid according to above methodology was not conducted. Statstcal analysis was provided with a program Statstca for Windows version 6.0. The mean calculated volume of loading was 456±62 ml of Gelaspan. 19 (73%) patents had a response to VL as an increase of SV>13% (p<0.05). At the same tme values of HR, MAP and SVRI did not signifcantly change. Afer inducton of anesthesia POH appeared in 4 (15%) of patents with the mean level of MAP minimum value 57±12 mm Hg. In all patents SVRI decreased to 1780±235 din/cm×sec-5 (p<0.05) and in patents with POH – reached a value of 1400±210 din/cm×sec-5 (p<0.05). Retrospectve analysis of 68 anesthetc charts revealed POH in 27 (25%) patents (p <0.05). So, we found that volume loading mode by colloid 6 ml/kg of IBW is adequate and safe for preoperatve optmizaton of volemic status in obese patents that provides almost 50% reducton in the risk of hypotension afer inducton of general anesthesia and indirectly confrms a status of output hypovolemia in them.

obesity, laparoscopic surgery, volemic status

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«Bulletin of problems biology and medicine» Issue 1 Part 2 (143), 2018 year, 108-112 pages, index UDK 616-089.163:612.13]-056.257

10.29254/2077-4214-2018-1-2-143-108-112