Comparison of Two Different Norepinephrine Bolus Doses for Management of Spinal Anesthesia-Induced Maternal Hypotension

Comparison of Two Different Norepinephrine Bolus Doses for Management of Spinal Anesthesia-Induced Maternal Hypotension

Comparison of Two Different Norepinephrine Bolus Doses for Management of Spinal Anesthesia-Induced Hypotension in Cesarean Section: A Randomized Controlled Study

In this study the investigators will compare two doses of norepinephrine bolus (6 mcg and 8 mcg) in management of maternal hypotensive episode after spinal block during cesarean delivery.

Maternal hypotension after spinal anesthesia is a common and serious complication during cesarean delivery. Despite all preventive measures, the incidence of hypotension is still around 20%. In these cases, maternal hypotension treatment is usually required using vasopressor boluses. One of the vasopressors commonly used during cesarean delivery is norepinephrine, especially recently. Although phenylephrine has long been the first choice for the prevention and treatment of maternal hypotension, its use may cause bradycardia and decreased maternal cardiac output. Norepinephrine is an alpha adrenergic agonist with weak beta adrenergic agonistic activity; therefore, it does not cause significant cardiac depression like phenylephrine. Norepinephrine has been introduced for use during cesarean delivery with promising results. Several previous studies have investigated the efficacy of norepinephrine infusion in preventing maternal hypotension. A dose-response study investigated the best dose of Norepinephrine for the prevention of hypotension. In the dose-response study mentioned above, a dose of 6 mcg was reported as the best dose for prophylaxis against hypotension. There are very limited studies investigating the best bolus dose of norepinephrine for the treatment of maternal hypotensive episode, and the optimal dose recommendation is uncertain. In this study, researchers will investigate the efficacy and adverse effects of two bolus doses of norepinephrine (6 mcg and 8 mcg) in the management of a maternal hypotensive episode after subarachnoid block during cesarean delivery.

Mothers in this group will receive a bolus of Norepinephrine 6 mcg for management of hypotensive episode after spinal anesthesia using Bupivacaine hydrochloride.

Mothers in this group will receive a bolus of Norepinephrine 8 mcg for management of hypotensive episode after spinal anesthesia using Bupivacaine hydrochloride.

An intravenous bolus of norepinephrine 6 mcg will be administered for management of maternal hypotension.

An intravenous bolus of norepinephrine 8 mcg will be administered for management of maternal hypotension.

Number of patients with successful management of a maternal hypotensive episode (defined as systolic blood pressure greater than 80% of baseline measurement and systolic blood pressure greater than 90 mmHg) Successful management is considered to be successful management if blood pressure does not fall below 90 mmHg and 80% of baseline measurement within 6 minutes after norepinephrine administration after hypotension develops.

Evaluation of the number of bolus noradrenaline doses and the total dose required for the treatment of maternal hypotension after spinal block.

Number of patients with reactive hypertension (defined as systolic blood pressure ≥120% from the baseline reading after administration of norepinephrine bolus).

The minimum score that can be obtained from this scale is 0 and the maximum is 10 points. Scoring will be calculated at 1 and 5 minutes immediately after birth. A score of 9 to 10 is consistent with a better clinical outcome, while a score of 8 or less will be considered a poor clinical outcome.

the number of patients with side effects (Nausea, vomiting, headache, tinnitus, arrhythmia, chest pain, etc.)

Comparison of the rates of change in heart rate in measurements before and after two different bolus doses of noradrenaline.

Inclusion Criteria: Woman, ASA I-II, 18-49 age range, Actual body weight >50 kg,<90 kg Actual height >150cm, <180cm Patients undergoing surgery under elective conditions and emergency cases for non-bleeding reasons Fasting period is appropriate, Term pregnancy (38-42 weeks), Patients without cardiovascular disease Spinal block that does not reach the high level (<T4), Patients without diagnosis of stage 2 or higher hypertension hypertension (Stage 2 hypertension is defined as a systolic blood pressure of more than 160 mmHg and a diastolic blood pressure of more than 90 mmHg.), Patients without vasoactive drug use, Preop Systolic Blood Pressure >90 mmHg, Bleeding less than 750 ml, Patients who signed the informed consent form to be included in the study Exclusion Criteria: ASA III-IV, Pregnant women outside the age range of 18-49, Actual body weight >90kg, <50kg Actual height >180cm, <150cm Patients with inappropriate fasting time Preterm pregnancy (<38 weeks) or postterm pregnancy (>42 weeks) Bleeding amount more than 750 ml Emergency surgery with bleeding (previa, placental abruption, etc.)- Pregnant with cardiovascular system disease, High block level (>T4) Having a diagnosis of stage 2 or higher hypertension hypertension (Stage 2 hypertension is defined as a systolic blood pressure of more than 160 mmHg and a diastolic blood pressure of more than 90 mmHg.), Use of vasoactive drugs, Preop Systolic Blood Pressure <90 mmHg Patients who did not sign the informed consent form to be included in the study

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