Hypotension spinal anaesthesia

PROCARBAZINE SPINAL ANAESTHETICS Risk of hypotensive episodes Uncertain Recommendation is to discontinue procarbazine for at least 10 days before elective spinal anaesthesia... 

Extradural (epidural) anaesthesia is used in the thoracic, lumbar and sacral (caudal) regions. Lumbar epidurals are used widely in obstetrics and low thoracic epidurals provide excellent analgesia after laparotomy. The drug is injected into the extradural space where it acts on the nerve roots. This technique is less likely to cause hypotension than spinal anaesthesia. Continuous analgesia is achieved if a local anaesthetic, often mixed with an opioid, is infused through an epidural catheter. 

Subarachnoid (intrathecal) block (spinal anaesthesia). By using a solution of appropriate specific gravity and tilting the patient the drug can be kept at an appropriate level. Sympathetic nerve blockade causes hypotension. Headache due to CSF leakage is virtually eliminated by using very narrow atraumatic penal point needles. 

Williams NE. Profound bradycardia and hypotension following spinal anaesthesia in a patient receiving an ACE inhibitor an important drug interaction Eur J Anaesthesiol 1999 16(ll) 796-8. 

Webb AA, Shipton EA. Re-evaluation of i.m. ephedrine as prophylaxis against hypotension associated with spinal anaesthesia for Caesarean section. Can J Anaesth 1998 45(4) 367-369. 

An 86-year-old man who had been reeeiving captopril 25 mg twice daily and bendroflumethiazide 25 mg daily [sic] for hypertension, underwent a transurethral resection of his prostate under spinal anaesthesia using 3 to 3.5 mL of heavy bupivacaine 0.5%. At the end of surgery, he was returned to the supine position and suddenly developed a severe sinus bradycardia (35 bpm), his arterial blood pressure fell to 65/35 nunHg and he became unrousable. Treatment with head-down tilt, oxygen and 1.2 mg of atropine produced rapid improvement in cardiovascular and cerebral function. A further hypotensive episode (without bradycardia) occurred approximately one hour later, which responded rapidly to 4 mg of methoxamine. ... 

Spinal anaesthesia ean produce bradyeardia and a fall in cardiae output resulting in arterial hypotension, whieh may be magnified by the action of the antihypertensive drug, and by hypovolaemia. Other factors probably contributed to the development of this interaction in these partieular patients. 

Williams NE, Profound bradycardia and hypotension following spinal anaesthesia in a patient... 

A study involving 40 elderly patients undergoing spinal anaesthesia found that bupivacaine 9 mg, with fentanyl 20 micrograms reduced the incidence of hypotension compared with bupivacaine 11 mg alone. Respiratory rates were not depressed in either group. The rate of failed spinal block and discomfort was similar in both groups. The addition of the fentanyl allowed a reduction in the minimum dose of bupivacaine to produce an adequate block, and consequently less hypotension. ... 

Physicians should also avoid the use of indirectly-acting vasoconstrictor amines such as ephedrine, mephentermine and metaraminol for reversing hypotension during spinal anaesthesia in patients taking MAOIs or who have recently stopped these (within the previous 2 weeks). 

Alahuhta S, Rasanen J, Jouppila P, Jouppila R, Hollmen Al. Ephedrine and phenylephrine for avoiding maternal hypotension due to spinal anaesthesia for caesarean section. Effects on uteroplacental and fetal haemodynamics, hit J Obstet Anesth 1992 1(3) 129-34. 

Ayorinde BT, Buczkowski P, Brown J, Shah J, Buggy DJ. Evaluation of preemptive intramuscular phenylephrine and ephedrine for reduction of spinal anaesthesia-induced hypotension during Caesarean section. Br J Anaesth 2001 86 (3) 372-6. 

Mohta M, Janani SS, Sethi AK, Agarwal D, Tyagi A Comparison of phenylephrine hydrochloride and mephentermine sulphate for prevention of post spinal hypotension. Anaesthesia 2010 65(12) 1200-5. 

Khavandi A, Gatward JJ, Whitaker J, Walker P. Myocardial infarction associated with the administration of intravenous ephedrine and metaraminol for spinal-induced hypotension. Anaesthesia 2009 64(5) 563-6. 

Rifampicin Profound hypotension following propofol induction of anaesthesia in a patient treated with two preoperative doses of rifampicin for antibiotic prophylaxis prior to spinal surgery is reported [96 ]. Anecdotal reports of similar experiences within the same institution prompted a retrospective case-control study... 

Foetal depression during spinal and epidural obstetric anaesthesia occurs secondary to maternal hypotension or as a result of placental transfer of the local anaesthetic agent (8, 10 -, 13 ). In this respect, bupivacaine was found to have a low foeto-maternal drug concentration ratio (16 -). When caudal anaesthesia is used, direct injection of the local anaesthetic drug into the foetus is possible (13, Other causes... 

Ephedrine hydrochloride 3 mg/mL solution, reversal of hypotension from spinal or epidural anaesthesia by slow intravenous injection adult dose 3-6 mg repeated every 3-4 minutes according to response to max. 30 mg. 

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