Is bolus norepinephrine dose as affective as ephedrine in preventing spinal anesthesia-induced hypotension in cesarean delivery?

Abstract

Objective: Spinal anesthesia is the preferred technique in cesarean delivery. Hypotension is the most common and concerning adverse effect (>80%) if no prophylaxis is given, which is major cause of maternal and fetal morbidity. Current literature suggests that vasopressor therapy is mainstay in prevention and management of spinal anesthesia-induced hypotension. Here, we aimed to compare the effects of prophylactic intravenous ephedrine and norepinephrine boluses on hypotension incidence in elective cesarean delivery under spinal anesthesia.
Materials and methods: The study included 62 term pregnant women (ASA II) with baseline systolic blood pressure (SBP) of 90-140 mmHg who were scheduled for elective cesarean section under spinal anesthesia. Ephedrine (10 mg, IV bolus) and norepinephrine (6 µg, IV bolus) were given simultaneously with spinal induction in group E and N, respectively. Hypotension was defined as SBP below 90% of baseline value (10% decrease from baseline) and respective agents in each group were given at same doses for treatment.
Results: Hypotension incidence was comparable in group E and N (64.5% vs. 74.2%, respectively). Severe hypotension (defined as SBP <80% of baseline) incidence was 32.3% in both groups. Tachycardia incidence and attacks were significantly higher in group E (p<0.01). Umbilical vein pH values was significantly higher in group E than group N (p<0.05). Fetal acidosis (defined as pH<7.20) was observed only in one newborn from group N.
Conclusion: Prophylactic ephedrine and norepinephrine IV boluses showed comparable efficacy in preventing and treating spinal anesthesia-induced hypotension. Both agents failed to decrease hypotension incidence.

Keywords

• Cesarean
• spinal anesthesia
• norepinephrine
• ephedrine
• hypotension

Sezaryen doğumlarda spinal anesteziye bağlı hipotansiyonu önlemede bolus doz norepinefrin efedrin kadar etkili midir?

Öz

Amaç: Spinal anestezi, sezaryen doğumlarda tercih edilen bir anestezi tekniğidir. Profilaktik tedavi yapılmadığında en yaygın ve korkulan yan etkisi; %80'in üzerinde görülen, anne ve fetüs için önemli morbidite sebebi olan hipotansiyondur. Güncel literatür, spinal anestezi kaynaklı hipotansiyonun önlenmesi ve tedavisinde en önemli basamağın vazopressör desteği olduğunu bildirir. Bu çalışmada spinal anesteziyle yapılan elektif sezaryen doğumlarda, profilaktik verilen intravenöz (İV) bolus efedrin ve norepinefrinin hipotansiyon insidansına etkilerini karşılaştırmayı amaçladık.
Gereç ve yöntem: Bu çalışmaya spinal anesteziyle elektif sezaryen yapılacak, ASA II fiziksel durumunda, termde ve bazal sistolik kan basıncı değerleri (SKB) 90-140 mmHg aralığında olan 62 gebe dâhil edildi. Spinal anesteziyle eş zamanlı olarak, efedrin grubuna (Grup E) 10 mg İV bolus efedrin, norepinefrin grubuna (Grup N) 6 µg İV bolus norepinefrin profilaktik olarak uygulandı. SKB’nin, bazalin %90’ının altına düşmesi (bazal değerden %10 düşük olması) hipotansiyon olarak tanımlandı ve tedavi için her gruba kendi ilaçları aynı dozlarda verildi.
Bulgular: Hipotansiyon insidansı Grup E ve Grup N’de sırasıyla %64,5 ve %74,2 olarak benzerdi. SKB’nin bazalin %80’inin altına düşmesi (bazal değerden %20 düşük olması) olarak tanımlanan ciddi hipotansiyon insidansı, iki grupta da %32,3 ile daha düşük oranlarda bulundu. Taşikardi insidansı ve atakları, Grup E’de önemli ölçüde daha yüksekti (p<0,01). Umbilikal ven kan gazı pH değerleri, Grup E de Grup N’ye göre daha yüksekti (p0,05). Sadece Grup N’de ve tek bir yenidoğanda, pH’ın 7,20’den düşük olması şeklinde tanımlanan fetal asidoz görüldü.
Sonuç: İV profilaktik ve bolus olarak uyguladığımız efedrin ve norepinefrin spinal anesteziye bağlı hipotansiyonu önlemede ve tedavi etmede benzer etkinlikteydi. Her iki ajan da hipotansiyon insidansını azaltmada yeterli etkinlik gösteremedi.

Anahtar Kelimeler

• Sezaryen
• spinal anestezi
• norepinefrin
• efedrin
• hipotansiyon

Kaynakça

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