Severe hypotension with loss of motor evoked potentials during cervical surgery prompting immediate cardiovascular resuscitation.

BACKGROUND: Intraoperative neuromonitoring (IONM) is a well-established adjunct to spinal surgery to ensure safety of the neural elements.IONM has extremely high sensitivity and specificity for impending neurologic damage. In very rare instances, hypoperfusion of the cord may lead to a loss of IONM modalities that may be reversed if blood pressure issues responsible for the drop out of potentials are immediately addressed. CASE DESCRIPTION: The authors describe a case in which IONM documented hypoperfusion of the cord intraoperatively due to hypotension. Recognition of this problem and reversal of the hypotension resulted in normalization of postoperative function. CONCLUSION: The use of IONM allowed for quick recognition of an impending neurological insult during spinal deformity surgery. Prompt response to signaling changes allowed for the correction of hypotension and favorable neurologic outcome.

Methylnaltrexone bromide: research update of pharmacokinetics following parenteral administration.

INTRODUCTION: Opioid-induced constipation is a major side effect of the use of opioid pain medications in a palliative care population. At present, the only approved treatment for opioid-induced constipation is methylnaltrexone bromide subcutaneous injection. Methylnaltrexone is a peripherally restricted opioid antagonist with µ-opioid receptor selectivity that can reduce opioid activity in peripheral organs such as the gastrointestinal tract while sparing the pain relief afforded by the pain medications. AREAS COVERED: This article addresses the pharmacokinetics of parenterally administered methylnaltrexone, including the studies in humans that form the basis for our understanding, and information on the disposition, metabolism and elimination of the drug. From this review, the reader will gain an understanding of the body's handling of methylnaltrexone following intravenous or subcutaneous administration. EXPERT OPINION: Studies conducted to date indicate that methylnaltrexone has high bioavailability after subcutaneous administration at therapeutic dose levels, a terminal half-life of ∼ 8 - 9 h, minimal metabolism, elimination involving renal and non-renal routes, and a limited potential for drug-drug interactions. Combined with high efficacy and good tolerability, the predictable pharmacokinetic behavior of methylnaltrexone facilitates its successful utilization in clinical practice for the treatment of opioid-induced constipation in patients with advanced medical illness.