Anesthesia postoperative care

Remifentanil Dosing Guidelines - General Anesthesia and Continuing as an Analgesic into the Postoperative Care Unit or... 

Due to improvements in anesthesia and postoperative care, surgical correction of the exstrophied bladder and osteotomies can be done safely within the neonatal period. Since newborns are under the influence of the maternal hormone of Relaxin, bladder closure within 72 h of life is performed. At this age, there is a good chance of achieving pelvic closure without osteotomies in some patients. 

Although opioid anesthesia is particularly useful in patients with compromised myocardial function, the opioids depress respiration by inhibiting the responsiveness of the medullary respiratory center to PCO2 and alter the rhythm of breathing. Consequently, it is necessary to assist ventilation intraoperatively. Since respiratory depression may extend into the postoperative period as a result of drug accumulation in the tissues, the use of opioids whose clearances are slow, remain most appropriate for patients who are expected to require postoperative ventilatory care. 

Respiratory depression becomes an important side-effect when opioids are used for postoperative pain treatment, since the anesthetic agent and most adjuncts of anesthesia induce a long-lasting depressant effect on respiration, which can increase the opioid effects up to respiratory arrest. Therefore careful supervision of respiration during the postoperative period is mandatory (Mulroy, 1996). Opioid-induced respiratory depression can be interrupted by the opioid antagonist naloxone. 

Preterm infants can become apneic during the immediate postoperative period, even if the ventilatory response to CO2 is not depressed after halothane anesthesia (12). In a prospective study in 167 preterm infants after inguinal herniorrhaphy with halothane/nitrous oxide anesthesia, only one had an episode of apnea up to 2 days postoperatively however, the authors recommended careful monitoring until complete recovery from anesthesia has occurred (13). 

A 76-year-old woman with previous exposure to isoflurane 3 years earlier underwent an above-knee amputation for a liposarcoma using isoflurane anesthesia. On day 3 postoperatively she became febrile and confused. Bacterial cultures later showed Staphylococcus aureus in the sputum and Escherichia coli in the urine. Associated hypotension for 2 hours resolved with inotropic support and here renal function remained normal. On day 6 she became jaundiced and developed further hypotension. Despite intensive care treatment she died on day 7. An autopsy showed centrilobular necrosis consistent with drug-induced hepatitis. All liver serology was negative. 

Remifentanil is an opioid analgesic that is indicated in analgesic use during the induction and maintenance of general anesthesia for inpatient and outpatient procedures and for continuation as an analgesic into the immediate postoperative period under supervision of an anesthesia practitioner and as an analgesic component of monitored anesthesia care. 

Immediately following cardiopulmonary bypass an elevation in pulmonary vascular resistance is poorly tolerated. The pulmonary vasculature of such children is prone to intense vasoconstriction in response to stress that may result in pulmonary hypertensive crises. This may necessitate therapeutic maneuvers, including continued paralysis and anesthesia, to blunt the stress response " and hyperventilation and alkalosis to promote pulmonary vasodilation. The realization that inhaled nitric oxide could act as a selective pulmonary vasodilator " holds great promise for this patient population, and a number of studies have attested to its efficacy both in the preoperative evaluation during cardiac catheterization and postoperatively in the intensive care unit " . 

Anesthesia must be clearly informed of surgical positioning, access or can-nulation sites in order to plan their monitoring and instrumentation. If necessary, postoperative hemodialysis, intermediate or intensive care should be organized at this time. 

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