Questions · Oxytocin Dosing and Uterotonic Escalation
10 questions, 0 approved. Approve them one at a time — a quiz shows nothing you have not.
Recall — derived from a kept point
In the dose-finding study of oxytocin at elective caesarean delivery in non-labouring women, what was the ED90 for adequate uterine contraction, how does it compare with the dose historically given, and at what dose did every woman respond?
Answer: The ED90 was 0.35 IU — a fraction of the 5 IU historically given — with 100% response by 1.0 IU.
The ED90 in a non-labouring elective caesarean is 0.35 IU, which is why the historical 5 IU was always more than the uterus needed.
Source claim: The ED90 for adequate uterine contraction at elective caesarean in non-labouring women was 0.35 IU — a fraction of the 5 IU historically given — with 100% response by 1.0 IU.
Oxytocin Requirements at Elective Cesarean Delivery: A Dose-Finding Study, Obstetrics and gynecology 2004
recall · CA-1 · phrased by llm
A woman who has been on an oxytocin infusion through labour now needs a caesarean. Explain the receptor-level reason her oxytocin dosing cannot be assumed to be the same as for an elective non-labouring patient.
Answer: Prior exposure to oxytocin desensitises the uterine oxytocin receptor, so a woman already on an oxytocin infusion in labour will need different dosing than an elective case.
The receptor she has been bathing in oxytocin all day is desensitised, so her dosing is a different problem from the elective case.
Source claim: Prior exposure to oxytocin desensitises the uterine oxytocin receptor, so a woman already on an oxytocin infusion in labour will need different dosing than an elective case.
Oxytocin for Labour and Caesarean Delivery: Implications for the Anaesthesiologist, Current opinion in anaesthesiology 2011
recall · CA-2 · phrased by llm
State what the international consensus statement recommends for how oxytocin should be administered at caesarean section, and give the two reasons it gives for that approach.
Answer: It recommends a small initial bolus of oxytocin followed by a titrated infusion. The two reasons are that standard recommended doses are higher than required, and that they risk acute cardiovascular effects.
Small bolus then titrate — the standard recommended doses are more than you need and carry acute cardiovascular risk for no added benefit.
Source claim: The international consensus recommends a small initial bolus of oxytocin followed by a titrated infusion, because standard recommended doses are higher than required and risk acute cardiovascular effects.
International Consensus Statement on the Use of Uterotonic Agents During Caesarean Section, Anaesthesia 2019
recall · CA-2 · phrased by llm
In the network meta-analysis of pharmacologic agents for preventing postpartum haemorrhage after caesarean delivery, state the comparison made between carbetocin and oxytocin, the specific outcome and the size of the effect, the certainty language used, and what it concluded about how oxytocin is best started.
Answer: Across 46 trials, carbetocin probably reduced the need for additional uterotonics by 185 per 1000 cases versus oxytocin, and oxytocin worked best when started as a bolus. The effect is stated as 'probably', which is graded certainty short of certain, and it applies to the single outcome of needing additional uterotonics — not to blood loss, transfusion, or any other endpoint.
Carbetocin probably spares 185 additional-uterotonic doses per 1000 cases versus oxytocin — 'probably', and only for that one outcome.
Source claim: In a network meta-analysis of 46 trials, carbetocin probably reduced the need for additional uterotonics by 185 per 1000 cases versus oxytocin, and oxytocin worked best when started as a bolus.
Preventing Postpartum Hemorrhage After Cesarean Delivery: A Network Meta-Analysis of Available Pharmacologic Agents, American journal of obstetrics and gynecology 2022
recall · CA-3 · phrased by llm
A ___ IU slow bolus was noninferior to the standard 5 IU for 24-hour blood loss at elective caesarean, and produced less vomiting (6% versus 24%).
Answer: 3
A 3 IU slow bolus was noninferior to the standard 5 IU for 24-hour blood loss at elective caesarean, and produced less vomiting (6% versus 24%).
An Observational Cohort Study of 3 Units Versus 5 Units Slow Intravenous Bolus Oxytocin in Women Undergoing Elective Caesarean Delivery · PMID 29151071
recall · CA-2 · phrased by derived
Bolus-plus-infusion regimens gave slightly less blood loss than bolus alone, initial boluses under ___ IU reduced nausea, and total doses of 5-9 IU increased the need for additional uterotonics versus 10-19 IU.
Answer: 5
Bolus-plus-infusion regimens gave slightly less blood loss than bolus alone, initial boluses under 5 IU reduced nausea, and total doses of 5-9 IU increased the need for additional uterotonics versus 10-19 IU.
Intravenous Oxytocin Dosing Regimens for Postpartum Hemorrhage Prevention Following Cesarean Delivery: A Systematic Review and Meta-Analysis · PMID 33957113
recall · CA-2 · phrased by derived
The point with one number taken out. No model wrote any of this: the stem is the sentence you reviewed, minus a digit, and the paper it came from is named beneath it.
Open prompts
How does your plan change if the patient is not optimised?
open · CA-2 · phrased by derived
What is the physiology behind what we just did?
open · CA-2 · phrased by derived
Talk me through the trade-off you made there.
open · CA-2 · phrased by derived
What would make you abandon this plan and do something else?
open · CA-2 · phrased by derived
Questions only — nothing here asserts anything, which is why a model is allowed to phrase them. Where no model was reachable these are the level defaults.