BACKGROUND: This study was a proof of concept of a novel means to evaluate microcirculatory changes during spinal anesthesia for cesarean delivery. It sought to examine the distributive circulatory effects of spinal anesthesia and evaluate the impact of phenylephrine administration on the microcirculation of these women. METHODS: After Research Ethics Board approval, healthy, non-laboring pregnant women with singleton, term pregnancies scheduled for elective cesarean delivery were recruited. Participants were randomly assigned to receive either phenylephrine infusion or phenylephrine bolus. Spinal anesthesia was standardized. A sidestream dark-field (SDF) MicroScan® video microscope was applied to the sublingual mucosa to obtain microcirculation videos in five different visual fields. Videos were made before and after spinal anesthesia. The resultant videos were analyzed randomly and blindly. The mean microvascular flow index (MFI) values were compared before and after spinal anesthesia. The difference in MFI following spinal anesthesia was compared between phenylephrine infusion and bolus groups. RESULTS: Thirty-two patients were recruited for the study; 22 patients had complete video sets for analysis. Baseline characteristics were similar between the two groups, including preoperative hemodynamics. There were no significant differences between pre- and post-spinal MFI. The post-spinal MFI within the infusion group (mean ± standard deviation: 2.74 ± 0.21) was not significantly different from the bolus group (2.56 ± 0.42, P = 0.22). CONCLUSION: Despite theoretical physiological implications of spinal anesthesia and phenylephrine on the microcirculation, significant alteration of the MFI was not observed between pre- and post-spinal anesthesia (within group). Additionally, despite an eight-fold larger phenylephrine dose for continuous infusion prophylaxis used in this group of women, this did not result in a significant alteration of the microcirculation compared to those who received phenylephrine treatment for hypotension (between groups).

Department of Anesthesia Intensive care and Perioperative Medicine Masaryk Hospital Usti nad Labem Czech Republic

Department of Anesthesia Pain Management and Perioperative Medicine Dalhousie University Halifax NS Canada

Department of Women's and Obstetric Anesthesia IWK Health Centre Halifax NS Canada

Zobrazit více v PubMed

Lee JE, George RB, Habib AS. Spinal-induced hypotension: Incidence, mechanisms, prophylaxis, and management: Summarizing 20 years of research. Best Pract Res Clin Anaesthesiol. 2017;31(1):57–68. doi: 10.1016/j.bpa.2017.01.001. PubMed DOI

Habib AS. A review of the impact of phenylephrine administration on maternal hemodynamics and maternal and neonatal outcomes in women undergoing cesarean delivery under spinal anesthesia. Anesth Analg. 2012;114(2):377–390. doi: 10.1213/ANE.0b013e3182373a3e. PubMed DOI

Allen TK, George RB, White WD, Muir HA, Habib AS. A double-blind, placebo-controlled trial of four fixed rate infusion regimens of phenylephrine for hemodynamic support during spinal anesthesia for cesarean delivery. Anesth Analg. 2010;111(5):1221–1229. doi: 10.1213/ANE.0b013e3181e1db21. PubMed DOI

Cooper DW, Carpenter M, Mowbray P, Desira WR, Ryall DM, Kokri MS. Fetal and maternal effects of phenylephrine and ephedrine during spinal anesthesia for cesarean delivery. Anesthesiology. 2002;97(6):1582–1590. doi: 10.1097/00000542-200212000-00034. PubMed DOI

Ngan Kee WD, Khaw KS, Lau TK, Ng FF, Chui K, Ng KL. Randomised double-blinded comparison of phenylephrine vs ephedrine for maintaining blood pressure during spinal anaesthesia for non-elective Caesarean section*. Anaesthesia. 2008;63(12):1319–1326. doi: 10.1111/j.1365-2044.2008.05635.x. PubMed DOI

Ngan Kee WD, Lee A, Khaw KS, Ng FF, Karmakar MK, Gin T. A randomized double-blinded comparison of phenylephrine and ephedrine infusion combinations to maintain blood pressure during spinal anesthesia for cesarean delivery: the effects on fetal acid-base status and hemodynamic control. Anesth Analg. 2008;107(4):1295–1302. doi: 10.1213/ane.0b013e31818065bc. PubMed DOI

den Uil CA, Lagrand WK, Spronk PE, van der Ent M, Jewbali LS, Brugts JJ, Ince C. et al. Low-dose nitroglycerin improves microcirculation in hospitalized patients with acute heart failure. Eur J Heart Fail. 2009;11(4):386–390. doi: 10.1093/eurjhf/hfp021. PubMed DOI

Elbers PW, Ozdemir A, van Iterson M, van Dongen EP, Ince C. Microcirculatory imaging in cardiac anesthesia: ketanserin reduces blood pressure but not perfused capillary density. J Cardiothorac Vasc Anesth. 2009;23(1):95–101. doi: 10.1053/j.jvca.2008.09.013. PubMed DOI

Massey MJ, Shapiro NI. A guide to human in vivo microcirculatory flow image analysis. Crit Care. 2016;20:35. doi: 10.1186/s13054-016-1213-9. PubMed DOI PMC

Abdo I, George RB, Farrag M, Cerny V, Lehmann C. Microcirculation in pregnancy. Physiol Res. 2014;63(4):395–408. PubMed

De Backer D, Creteur J, Dubois MJ, Sakr Y, Vincent JL. Microvascular alterations in patients with acute severe heart failure and cardiogenic shock. Am Heart J. 2004;147(1):91–99. doi: 10.1016/j.ahj.2003.07.006. PubMed DOI

De Backer D, Creteur J, Preiser JC, Dubois MJ, Vincent JL. Microvascular blood flow is altered in patients with sepsis. Am J Respir Crit Care Med. 2002;166(1):98–104. doi: 10.1164/rccm.200109-016OC. PubMed DOI

Groner W, Winkelman JW, Harris AG, Ince C, Bouma GJ, Messmer K, Nadeau RG. Orthogonal polarization spectral imaging: a new method for study of the microcirculation. Nat Med. 1999;5(10):1209–1212. doi: 10.1038/13529. PubMed DOI

De Backer D, Hollenberg S, Boerma C, Goedhart P, Buchele G, Ospina-Tascon G. et al. How to evaluate the microcirculation: report of a round table conference. Critical Care. 2007;11(5):101. doi: 10.1186/cc6118. PubMed DOI PMC

George RB, Munro A, Abdo I, McKeen DM, Lehmann C. An observational assessment of the sublingual microcirculation of pregnant and non-pregnant women. Int J Obstet Anesth. 2014;23(1):23–28. doi: 10.1016/j.ijoa.2013.08.013. PubMed DOI

George RB, DesRoches J, Abdo I, Lehmann C. Maternal microcirculation and sidestream dark field imaging: a prospective assessment of the association between labour pain and analgesia on the microcirculation of pregnant women. Clin Hemorheol Microcirc. 2015;60(4):389–395. doi: 10.3233/CH-141851. PubMed DOI

Maier S, Hasibeder WR, Hengl C, Pajk W, Schwarz B, Margreiter J, Ulmer H. et al. Effects of phenylephrine on the sublingual microcirculation during cardiopulmonary bypass. Br J Anaesth. 2009;102(4):485–491. doi: 10.1093/bja/aep018. PubMed DOI

Ohlmann P, Jung F, Mrowietz C, Alt T, Alt S, Schmidt W. Peripheral microcirculation during pregnancy and in women with pregnancy induced hypertension. Clin Hemorheol Microcirc. 2001;24(3):183–191. PubMed

van Elteren HA, Ince C, Tibboel D, Reiss IK, de Jonge RC. Cutaneous microcirculation in preterm neonates: comparison between sidestream dark field (SDF) and incident dark field (IDF) imaging. J Clin Monit Comput. 2015;29(5):543–548. doi: 10.1007/s10877-015-9708-5. PubMed DOI PMC

Sharawy N, Hussein A, Hossny O, Refaa A, Saka A, Mukhtar A, Whynot S. et al. Effects of haemoglobin levels on the sublingual microcirculation in pregnant women. Clin Hemorheol Microcirc. 2016;64(2):205–212. doi: 10.3233/CH-162064. PubMed DOI