C&P: Physiological Effects of Inhalational Agents Flashcards Preview

FRCA Anaesthesia > C&P: Physiological Effects of Inhalational Agents > Flashcards

Flashcards in C&P: Physiological Effects of Inhalational Agents Deck (13):
1

Cardiac Contractility

Halothane: massive fall
Isoflurane: some fall
Sevoflurane: some fall
Desflurane: no change
Nitrous oxide: some fall

2

Heart Rate

Halothane: big fall
Isoflurane: big rise
Sevoflurane: no change
Desflurane: rise (big rise at >1.5 mac)
Nitrous oxide: no change

3

Systemic Vascular Resistance

Isoflurane + desflurane--big fall
All others moderate fall

4

Blood Pressure

Sevoflurane is the least fall, all have overall falls

5

Sensitivity to Catecholamines

Halothane: increased +++
No change to others

6

Respiratory Rate

Increased for all

7

Effect of PaCO2

Same for nitrous and halothane
Increased for all others

8

Bronchodilation

Halothane and sevoflurane bronchodilate (also enflurane)
Desflurane is an irritant

9

Cerebral Blood Flow

Halothane: big increase
Isoflurane: increased
Sevoflurane: preserved autoregulation
Desflurane: increase
Nitrous oxide: increase

10

Cerebral Metabolic Rate (O2 consumption)

Reduced for all except nitrous oxide (moderate increase)

11

EEG

Burst suppression except enflurane (epileptiform activity)

12

Uterus

Significant relaxation in all volatiles except nitrous

13

Misc

Halothane: hepatotoxic, stored in 0.01% thymol, light sensitive
Isoflurane: coronary steal, maintains renal blood flow
Sevoflurane: renal toxicity
Desflurane: nil
Nitrous oxide: oxidizes cobalt ion in vitamin B12