4 Pre-op: Hemato e Coagulacao

Question 1

Em pacientes com Anemia Falciforme, qual o valor de Hb que necessita de transfusao?

Answer 1

• Manter Hb > 10

A more aggressive strategy (i.e., decreasing HbS concentration to <30%) is preferable for high-­risk surgery such as major cardiovascular or intracranial procedures.

Question 2

Em que momento do dia deve ser feita a cirurgia de pacientes com Anemia Falciforme?

Answer 2

• Manha, primeira do dia

The surgical admission should be planned to minimize preoperative dehydration (e.g., minimize fasting period, schedule procedure as an early morning case).

Question 3

Outpatient oral anticoagulant therapy includes vitamin K antagonists (e.g., warfarin) and DOACs. These agents increase perioperative bleeding, except in the case of very minor procedures.

• Em que situacoes podem ser mantidos no periodo perioperatorio? (3)

Answer 3

• Se não tiver fatores de risco relacionados ao paciente para sangramento (por exemplo, doença hepática, função renal anormal, complicações hemorrágicas prévias),
• Estiver programado para procedimentos sem risco significativo de sangramento (por exemplo, extração dentária, procedimentos cutâneos simples, cirurgia de catarata sem bloqueios bulbares)
• não esteja se considerando anestesia neuraxial.

Caso contrário, a terapia anticoagulante deve ser temporariamente suspensa antes da cirurgia.

Question 4

Quando suspender antagonistas da vitamina-K?

Answer 4

• 5 dias antes da cirurgia ou mais se INR > 5
• Checar INR 24h antes da cirurgia e dar Vit-K se INR > 1.5

Question 5

Some patients undergoing elective lower extremity joint replacement surgery may also receive an initial dose of warfarin before surgery for perioperative thromboprophylaxis.

The 2018 American Society of Regional Anesthesiologists (ASRA) guidelines state that neuraxial anesthesia can still be performed in these patients when only a single dose of warfarin had been administered ___1___ before surgery.

Answer 5

1. ≤24 hours

Question 6

The timing of preoperative discontinuation of DOACs should be guided by: (4)

Answer 6

• Droga Especifica
• Risco de sangramento do procedimento
• Funcao renal (eGFR)
• Plano de anestesia neuroaxial

Question 7

If bridging is planned, either LMWH or IV unfractionated heparin can be started two or more days after the last administrated dose of vitamin K antagonist (e.g., warfarin).

Bridging therapy should be started once the INR drops to ___1___

Answer 7

1. <2.0

Question 8

For patients with impaired renal function (eGFR <30 mL/min), IV heparin bridging is preferable, although some LMWH dosing adjustments remain possible if eGFR is in the range between 15
to 30 mL/min.IV unfractionated heparin is usually discontinued ___1___ before surgery to allow for normal intraoperative coagulation.

The last dose of bridg-
ing dose LMWH should be given ___2___ preoperatively to allow normalization of coagulation by the time of surgery (based on an assumption of normal renal function).

Especially for surgeries with high associated bleeding risk, only ___3___ the total daily dose of LMWH should be administered on the day prior to scheduled procedure.

Answer 8

1. four or more hours (4-6h)
2. 24 hours
3. half

Question 9

Both unfractionated heparin and LMWH are contraindicated in patients with an allergy to heparin or a history of heparin-­ induced thrombocytopenia (HIT). Options for bridging therapy in such patients include (4)

Answer 9

• argatroban (IV infusion),
• bivalirudin (IV infusion),
• fondaparinux (sub-
  cutaneous),
• Oral DOACs.

Question 10

The last prophylactic dose of LMWH should be ___1___ before any planned neuraxial block, whereas the last therapeutic dose (including bridging therapy) of LMWH should be ___2___ beforehand.

Preoperative unfractionated IV heparin should be stopped ___3___ before planned spinal or epidural anesthesia.

Answer 10

1. ≥12 hours
2. ≥24 hours
3. ≥6 hours

Question 11

Since 10% of platelets are turned over every 24 hours, and about 50,000/mm3 of normal functioning platelets are needed to control surgical bleeding, it is likely that aspirin need only be stopped ___1___ before surgery to mitigate risks of increased bleeding.

Continuation of aspirin until the time of surgery leads to increased bleeding during major noncardiac surgery, but not during cardiac surgery.

Answer 11

1. three days

Question 12

Specifically, aspirin should be continued in any patient
with a ___1___, ___2___, or ___3___.

Continuation of aspirin is not a contraindication to performance of neuraxial
blocks.

Answer 12

1. prior PCI,
2. high-­ grade IHD,
3. high-­ risk CVD (e.g., stroke within prior nine months).

Question 13

Except in patients with a ___1___, P2Y12 inhibitor therapy should be temporarily discontinued before elective surgery.

Answer 13

1. recent PCI

Question 14

The ACCP guidelines recommend specific time intervals for discontinuing these medications before elective noncardiac surgery: ___1___ for clopidogrel, ___2___ for ticagrelor, and ___3___ for prasugrel.

If a patient is being considered for a neuraxial block, the minimum time intervals are five to seven days for clopidogrel, five to seven days for ticagrelor, seven to ten days for prasugrel, ten days for ticlopidine, and three hours for cangrelor.

Answer 14

1. five days
2. three to five days
3. seven days

Question 15

There are minimal data on the safety of continuing dipyridamole in patients undergoing surgery; current ASRA guidelines recommend discontinuing extended-­ release dipyridamole ___1___ before performing any neuraxial block.

Answer 15

1. 24 hours

Question 16

Platelet glycoprotein IIb/IIIa inhibitors (e.g., abciximab, eptifibatide, tirofiban) exert profound effects on platelet aggregation.

Following administration, the time to restoration of normal platelet aggregation is ___1___ for abciximab, and ___2___ for eptifibatide and tirofiban. Neuraxial techniques should therefore be avoided until platelet function has recovered after platelet glycoprotein IIb/IIIa inhibitor administration.

Answer 16

1. 24 to 48 hours
2. 4 to 8 hours

Question 17

Recomendacoes de AINEs em Bloqueio de Neuroeixo

Answer 17

• Nao suspender

Question 18

Recomendacoes de anticoncepcionais orais no pre-op

Answer 18

Nao suspender

Question 19

Qual a pp medicacao que pode diminuir o efeito de contraceptivos hormonais por 7 dias apos o uso?

Answer 19

• Sugammadex

Oral contraceptive use should also be noted should the patient eventually receive sugammadex during the perioperative period. Sugammadex can decrease the efficacy of hormonal contraceptives, meaning that the patient will require an additional non hormonal contraceptive for seven days after sugammadex exposure.

Question 20

Recomencacoes a respeito de IMAOs no periop(3)

Answer 20

• Manter uso
• Evitar meperidina
• Evitar Efedrina

Question 21

Recomencacoes a respeito de Antidepressivos Triciclicos no periop(3)

Answer 21

• Manter
• ECG
• ↑resposta a vasopressores

Question 22

Recomencacoes a respeito de IRSR no periop

Answer 22

• Suspender apenas em cirurgias em que o sangramento pode ter sequela pos-op importante (Cirurgia Intracraniana)