Anesthetics, monitoring

Denisco RA, Drummond JN, Gravenstein JS. The effect of fatigue on the performance of a simulated anesthetic monitoring task. J Clin Monit 1987 3 22-24. 

Thom and coworkers published results on the stimulation of perivascular NO synthesis by oxygen [127], To perform this study a 200 pm diameter electrode (ISONOP200) was placed between the aorta and vena cava of anesthetized rats and mice (rodents) and then the rodents were placed inside a hyperbaric chamber. Inside the hyperbaric chamber the partial pressure of 02 was regulated/changed as NO concentration was monitored. Figure 1.11 shows that NO concentration increased as a function of 02 partial pressure. This experiment is important for understanding how NO synthesis, by NOS, is altered and regulated by 02. 

The effect of rifaximin on cardiovascular (CY) and respiratory systems was investigated in anesthetized rats and guinea pigs, respectively [59]. Rifaximin was given intraduodenally at doses up to 100 mg/kg and carotid pressure and flow as well as heart rate were continuously measured in rats while respiration amplitude and frequency were monitored in guinea pigs. The rifamycin derivative did not affect any of the measured parameters at any time after its administration. 

Weeks et al. (1963) reported that 80% of the 1,1-dimethylhydrazine administered via endotracheal tube to anesthetized mongrel dogs was retained in the respiratory tract. It was unclear if the retention was monitored only for the 51-64 min duration of exposure. 

Seelig, A., Allegrini, P. R. and Seelig, J. (1988). Partitioning of local anesthetics into membranes surface charge effects monitored by the phospholipid head-group, Biochim. Biophys. Acta, 939, 267-276. 

Monitor An apparatus which automatically records such physiological signs as respiration, pulse, and blood pressure in an anesthetized patient or one undergoing surgical or other procedures. [NIH]... 

Figure 9.15 presents an example of the in vivo measurements of the oxygen content in the arterial blood of dogs over a period of 10 h. The dots represent the batch gas analysis performed with a Nova Biomedical blood gas analyzer. The solid lines represent the analyses monitored by the instrument. Blood oxygen measurements were obtained continuously (not shown in the figure) about every 3 sec. Two different polymer solutions are shown. The measurements performed by the instrument are not affected by the presence of unmetabolized clots and/or anesthetics in the blood stream. Additionally, no deterioration of the signal was found after 10-h periods. 

Volatile anesthetic agents - Close perioperative monitoring is recommended in patients undergoing general anesthesia who are on amiodarone therapy as they may be more sensitive to the myocardial depressant and conduction effects of halogenated inhalational anesthetics. 

For all juveniles, there should be EEG monitoring during ECT and recording of seizure length by both direct observation of the motor fit and by the EEG. Prolonged seizures should be terminated by means of diazepam or further general anesthetic. 

Anesthetic techniques that have minimized adverse effects include the use of muscle relaxants and, more recently, nerve stimulators to assess adequacy of relaxation, the introduction of very rapid acting, short-duration barbiturates, and the use of atropinic agents to minimize the cardiovascular response to a combination of a seizure and anesthesia (93). In addition, 100% oxygenation (adequacy monitored by a pulse oximeter) with positive-pressure ventilation can minimize related cardiac events and memory disruption. 

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