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The Multidimensional Pain Inventory (MPI) and the MMPI have been used widely to assess chronic pain patients. This study examined the relationship between patient profile classifications generated by the MPI and psychopathology as measured by the MMPI. MPI Dysfunctional and Interpersonally Distressed means were significantly different than the MPI Adaptive Coper means on scales 4, 6, 7, and 8 of the MMPI. The Dysfunctional and Adapative Coper means were also significantly different on MMPI scale 2. MMPI profiles for 79% classified as Dysfunctional and 62% classified as Interpersonally Distressed displayed psychopathology as defined by significant two-point scale elevations. Only 23% of those classified as Adaptive Copers had significant two-point MMPI scale elevations.

This study examines the behavioral, sensory, motor and structural recovery during the first 2 months following a freeze (cryoprobe) lesion compared to a nerve crush (forceps). There is a complete loss of sensory and motor function following either type of lesion during the first 2 weeks of recovery. The toe spreading reflex and the sciatic functional index of locomotion behavior returned to normal without significant group differences. Latency times for the pain withdrawal reflex were slightly shorter in the cryoprobe group, but both groups returned to baseline during the second month. An improved regenerative pattern was suggested for the motor recovery in the cryoprobe group as expressed by the amplitude of the digital twitch tension curves. However, the respective curve areas were not different. Morphometric analysis indicated a significant reduction in the distal nerve cross-sectional area, an increase in the mean myelinated fiber density and an increase in the estimated total number of myelinated nerve fibers in both experimental groups. Mean fiber diameter and myelin sheath thickness had not fully returned to normal in either experimental group. Both the fiber size and myelin sheath thickness were significantly reduced in the cryoprobe group. In conclusion, the two lesion types have remarkably similar patterns of recovery. Functional data suggest that motor recovery precedes sensory recovery following a cryoprobe lesion.

A desire to prevent complications resulting from spinal surgery led to the development of intraoperative monitoring. Intraoperative electromyography (EMG) provides useful diagnostic information regarding nerve root function during spinal and peripheral nerve surgeries. The C-5 nerve root is considered particularly vulnerable to injury during cervical surgery. Despite advances in techniques, the incidence of postoperative C-5 palsy has not changed.The authors reviewed prospectively collected data obtained in 161 patients who underwent 171 cervical procedures. In 116 procedures, operative monitoring was modified to include continuous C-5 EMG from the deltoid muscle. In cases in which spontaneous C-5 activity occurred, an appropriate change in operative manipulation was made. A historical control group consisted of a retrospective review of 55 procedures that were monitored using conventional techniques. In the retrospective cohort, four (7.3%) of 55 patients presented after undergoing surgery for C-5 nerve root palsy. In each patient conventional monitoring revealed unremarkable findings. In the prospective cohort, intraoperative spontaneous EMG activity necessitated a change in either positioning or operative technique in three cases. Only one patient (0.9%) experienced postoperative C-5 palsy. Postoperative C-5 palsy occurred in no patient in whom there was no intra-operative evidence of root irritation (p0.03, chi-square test).The incidence of postoperative C-5 palsies was reduced from 7.3% to 0.9% due to intraoperative continuous EMG monitoring. No patient suffered a postoperative C-5 palsy when intraoperative evidence of root irritation was absent.

The risk of an endotracheal tube's combustion during laser airway surgery necessitates the use of special anesthetic techniques and equipment to prevent this complication. This study was designed to evaluate the Laser-Trach(TM), a new laser-resistant rubber endotracheal tube for use during laser airway surgery. The Laser-Trach endotracheal tubes that were evaluated were size 6.0 mm internal diameter (ID) red rubber endotracheal tubes which had been commercially wrapped by Kendall-Sheridan (Mansfield, Mass.) with copper foil tape and overwrapped with fabric. The fabric layer was saturated with water prior to our tests, as recommended by the manufacturer. The Laser-Trach endotracheal tubes were compared with plain (bare) size 6.0 mm ID Rusch red rubber endotracheal tubes. The tubes under study were positioned horizontally on wet towels in air and had 5 L x min(-1) of oxygen flowing through them. They were subjected to continuous laser radiation at 40 W from either a CO2 or an Nd-YAG laser. The Nd-YAG laser was propagated via a 600-micron fiber bundle. Each laser was directed perpendicularly at the shaft of the endotracheal tube being studied, and its output was continued until a blowtorch fire occurred or 60 seconds had elapsed. Sixty seconds of CO2 laser fire did not ignite any of the eight Laser-Trach endotracheal tubes tested. However, blowtorch ignition of all eight bare rubber tubes tested occurred after 0.87 +/- 0.21 (mean +/- SD) seconds of CO2 laser fire. Nd-YAG laser contact with the Laser-Trach endotracheal tubes caused the perforation and blowtorch ignition of all eight tubes tested after 18.79 +/- 7.83 seconds. This was a significantly (P

To determine unbiased patient preferences for either spinal or general anesthesia for upcoming surgeries.Prior to contact with anesthesia personnel, a simple questionnaire was completed by surgical patients to determine their demographic characteristics and previous anesthetic experiences. Their concerns regarding a list of complications of general and spinal anesthesia and their preferences for general or spinal anesthesia if either method could be used were also determined.University-affiliated suburban community hospital.The survey was completed by 254 patients. A preference for general over spinal anesthesia was expressed by 80.2% of the patients responding. They expressed significantly more concerns regarding nausea/vomiting, sore throat, feeling sleepy, and death with general anesthesia than with spinal anesthesia. Concerns of back pain, nerve damage and paralysis were statistically related to spinal anesthesia.This survey shows a strong patient preference for general anesthesia and a phobia for spinal anesthesia.

We determined whether propofol, thiopental, or 0.9% saline would serve as a growth medium for Candida albicans. In Part I, we investigated whether opening 20 propofol ampules would cause glass particles from the exterior of the ampule to fall into the emulsion and contaminate it. Each ampule was painted with red fingernail polish and its contents were passed through filter paper after it was opened in a routine manner. In Part II, a sample from a colony of C albicans was added to sterile vials containing 20 mL of either 0.9% saline, 1% propofol, or 2.5% thiopental. A 1-microL sample from each vial was then plated onto Sabaroud's dextrose plus brain-heart infusion (SABHI) agar at the following times after inoculation: 0, 3, 6, 16, and 24 h. The plates were incubated at 35 degrees C for 24 h and the number of colony-forming units counted. The filtration of two of the painted ampules in Part I revealed red glass fragments. In Part II, the saline and thiopental solutions did not increase the number of colonies of C. albicans by 24 h. However, the propofol, after a latent period between 6 and 16 h, supported the growth of C. albicans at a rapid rate. Our investigation shows that glass particles from the exterior of a propofol ampule can contaminate its contents when the ampule is opened in a routine manner. Furthermore, propofol provides an excellent growth medium for C. albicans. Thiopental and saline showed no growth. We conclude that the ability of propofol to grow C. albicans necessitates rigorous standards of sterility in its handling.

Study Objective: To determine whether metallic Y-pieces and elbows would halt the progression of a laser-induced endotracheal tube fire. Design: A segment of polyvinyl chloride endotracheal tube was attached to either an all-plastic anesthesia circle breathing system (n = 5) or a circuit consisting of a metal Y-piece and elbow with plastic hoses (n = 5). In each case, an Nd-YAG laser was used to ignite the endotracheal tube segment and attached anesthesia circuit as 5 L/min of oxygen was flowing through them. Setting: Research laboratory of a university-affiliated metropolitan medical center. Measurements and Main Results: The flames from the endotracheal tubes burned through the 22 mm hoses that were part of the all-plastic circuits in 49.5 ± 8.8 seconds (mean ± SD). In none of the trials with the metal components did the fire advance beyond the endotracheal tube's 15 mm adapter. Conclusions: Metal circuit components halt the progression of laser-induced endotracheal tube fires toward the anesthesia machine.

The potassium-titanyl-phosphate laser is being used for airway surgery and could cause an endotracheal tube fire. To determine whether five different metallic foil tapes or the Laser-Guard protective wrap would protect polyvinylchloride (PVC) endotracheal tubes from this laser, it was set to a power of 18 W and aimed at the wrapped endotracheal tube under study for up to 1 min while 5 L/min of oxygen flowed through the endotracheal tube. A plain (unwrapped) PVC endotracheal tube was studied also. The plain PVC endotracheal tube was ignited by the laser after 14 s. Potassium-titanyl-phosphate laser radiation did not significantly affect the nonadhesive sides of the foil tapes tested or the Laser-Guard covering. However, potassium-titanyl-phosphate laser radiation caused ignition or melting of underlying PVC endotracheal tubes when it was applied to the endotracheal tubes with the adhesive side of the foil tapes facing outward. It is concluded that only the Laser-Guard protective coating adequately protected the PVC endotracheal tubes tested under the conditions of this experiment.

Study Objective: To determine unbiased patient preferences for either spinal or general anesthesia for upcoming surgeries. Design: Prior to contact with anesthesia personnel, a simple questionnaire was completed by surgical patients to determine their demographic characteristics and previous anesthetic experiences. Their concerns regarding a list of complications of general and spinal anesthesia and their preferences for general or spinal anesthesia if either method could be used were also determined. Setting: University-affiliated suburban community hospital. Measurements and main results: The survey was completed by 254 patients. A preference for general over spinal anesthesia was expressed by 80.2% of the patients responding. They expressed significantly more concerns regarding nausea/vomiting, sore throat, feeling sleepy, and death with general anesthesia than with spinal anesthesia. Concerns of back pain, nerve damage and paralysis were statistically related to spinal anesthesia. Conclusions: This survey shows a strong patient preference for general anesthesia and a phobia for spinal anesthesia.

Patient infections related to the use of propofol have been reported. To investigate the growth of Staphylococcus aureus in propofol, thiopental, methohexital, etomidate, and 0.9% saline containing no bacteriostatic drug, these preparations were inoculated and samples were plated onto blood agar at

Thiosulfate concentrations and pharmacokinetics were studied in relation to sodium nitroprusside before, during, and after anesthesia. Normal thiosulfate concentrations were 1.13 +/- 0.11 mg/dl and 0.28 +/- 0.02 mg/dl in plasma and urine, respectively. Cholecystectomy patients had similar concentrations during surgery, with bile thiosulfate concentration of 13.72 +/- 2.95 mg/dl. Fasting patients and children had significantly higher plasma and urine thiosulfate concentrations. Over 99% of endogenous filtered thiosulfate was reabsorbed by the kidney in the average case. Coronary bypass patients had decreased plasma thiosulfate levels and increased excretion postoperatively. Disappearance of injected thiosulfate was biphasic; the distribution phase was dependent on the initial rate of injection, and the elimination phase depended on extracellular fluid turnover and renal excretion. Cholecystectomy patients on diuretics had a markedly increased rate of excretion, 56% within 100 min, versus normal subjects who excreted less than 50% in up to 18 h. In children, plasma thiosulfate did not change significantly, while blood cyanide concentration increased significantly during sodium nitroprusside administration and surgery. Thiosulfate did not change during recovery while cyanide decreased. Normal production of thiosulfate in humans may be limited; hence, continuous thiosulfate infusion may be required during sodium nitroprusside administration.

To test the efficacies of various antidotes to cyanide (CN) poisoning, the lethal dose of cyanide in dogs was estimated during constant infusion of potassium cyanide at a rate of 0.1 mg/kg/min. Additionally, arterial blood pressure, right ventricular pressure, heart rate, electrocardiogram, blood-gas and pH values, and whole blood and tissue CN concentrations were measured. The lethal dose in animals whose lungs were ventilated with room air was 2.4 +/- .2 mg/kg (mean +/- SE), while the whole-blood CN concentration was 438 +/- 40 micrograms/dl and the gracilis muscle concentration was 2.0 +/- .3 micrograms/100 g. A low dose of vitamin B12a (100 mg/kg), an infusion of thiosulfate (12 mg/kg/h), or ventilation with 100 per cent O2 increased the amount of CN needed to cause death. A bolus injection of nitrite (5 mg/kg), thiosulfate (150 mg/kg), or cysteine (450 mg/kg) increased the the protection from lethality even further. Protection against CN administration for the total 150-min period of observation was provided by a bolus injection plus a constant infusion of nitrite (5 mg/kg bolus plus 5 mg/kg/h). thiosulfate (30 mg/kg bolus plus 60 mg/kg/h), or vitamin B12a (50 mg/kg bolus plus 100 mg/kg/h). However, nitrite infusion produced high levels of methemoglobin 7.2 +/- 1.1 g/dl, while vitamin B12a infusion and cysteine injection, at the stated doses, did not prevent cyanide-induced circulatory failure. Therefore, thiosulfate appears to be the most effective and safest prophylactic agent against cyanide toxicity in dogs.

Ten male mongrel dogs were treated in Phase I with tranylcypromine, 6 mg/kg IM b.i.d., for 21 days. Dogs were anesthetized at weekly intervals before, during, and up to four weeks after drug treatment with a combination of amylbarbital, 25 mg/kg, 1% enflurane in 70:30 N2O:O2 and fentanyl, 500 mcg. Bolus IV injections of norepinephrine, 0.1-0.6 mcg/kg, and ephedrine, 0.03-0.12 mg/kg were given while continuously recording arterial blood pressure, lead II of the ECG, heart rate, and rectal temperature. Awakening times were noted. In Phase II, the dogs were given imipramine, 25 mg/kg IM b.i.d., for 21 days. During Phase III, 14 days of tranylcypromine, 7 days of tranylcypromine plus imipramine, and 7 days of imipramine were administered. Anesthetic techniques were repeated in phases II and III. The fourth phase consisted of tranylcypromine injections, 6 mg IM b.i.d., and anesthesia with amylbarbital, 25 mg/kg, 2.5% enflurane in 70:30 N2O:O2. Vasopressor challenges were repeated during each phase of the study. Following induction of anesthesia and prior to fentanyl challenge, baseline blood pressures and heart rates did not differ from control in Phase I, II, and III of this study. Responses to norepinephrine during all of the tranylcypromine phases were not significantly different from control but ephedrine responses were prolonged, peaking by the second week of treatment. During Phase II, dysrhythmias occurred following norepinephrine and ephedrine with one lethality following norepinephrine, 0.2 mcg/kg. Responses to norepinephrine and awakening times were significantly greater during Phase II compared to Phase I. In Phase III, during the first week of combined therapy the responses to norepinephrine were significantly greater than any other week of this phase. During Phase IV, resting blood pressure and the ephedrine responses were significantly increased during tranylcypromine when the anesthesia regimen did not include fentanyl. These results suggest that during initial treatment with tranylcypromine or imipramine, cardiovascular responses to vasopressor challenges were predicted by the pharmacology of the antidepressant. During tranylcypromine phases, we did not observe exaggerated cardiovascular effects during anesthesia and vasopressor challenges as had been previously reported.

A patient with a dissecting aortic aneurysm, Type 1, developed acute pulmonary edema unexplained by the usual etiologic factors. Pathologic evidence that bronchial arterial circulation was interrupted led us to hypothesize that pulmonary edema could be due to ischemia of the bronchial circulation. To test this hypothesis, two chronic studies were done in dogs. The first study consisted of selective ligation of the right posterior bronchial artery at its origin at the fifth or sixth intercostal artery. After recovery from surgery, biopsies were taken from the ipsilateral and contralateral lung at time periods from 5 hours to 11 days. Ischemic damage was found in seven of eight dogs (87.5%), and was confined to the right lung. Histological examination revealed initial congestion within 8 hours, followed by pulmonary edema within 72 hours, and finally, disruption of alveolar septa with small emphysematous bullae on the eleventh postoperative day. The left lung remained normal in histological appearance. The second study consisted of transplanting the bronchial artery to the pulmonary artery to create a low pressure system and low O(2) content, and to simulate a regional shock situation. In five of six dogs (83.3%), the anastomosis was occluded within 72 hours, probably due to pressure competition from small collateral bronchial circulation. However, in these five dogs, pulmonary vascular resistance increased by 53%, intrapulmonary shunting increased by 83%, and the alveolar-to-arterial oxygen gradient increased by 150 mm Hg. Pulmonary edema was again confined to the right lung. Bronchial arteriograms demonstrated the extensive and variable distribution of the bronchial circulation in dogs. In the sixth dog, the anastomosis remained patent with a left-to-right shunt, due to a larger bronchial arterial collateral circulation. In this animal, the pulmonary arterial resistance, intrapulmonary shunting, and alveolar-arterial O(2) gradient were normal. Pulmonary edema was absent in lung biopsies. Bronchial circulation is discussed with respect to its clinical implications for lung transplants, shock, thoracic aneurysms, and mediastinal surgery. The results of this study suggest that the systemic bronchial circulation is important for normal lung function.

We examined the biostimulating effects of helium-neon laser radiation (HeNe; 632.8 nm), pulsed infrared laser radiation (IR; 904 nm), and the two combined on skin wound healing in New Zealand white rabbits. Seventy-two rabbits received either (1) no exposure, (2) 1.65 J/cm2 HeNe, (3) 8.25 J/cm2 pulsed IR, or (4) both HeNe and IR together to one of two dorsal full-thickness skin wounds, daily, for 21 days. Wound areas were measured photographically at periodic intervals. Tissue samples were analyzed for tensile strength, and histology was done to measure epidermal thickness and cross-sectional collagen area. Significant differences were found in the tensile strength of all laser-treated groups (both the irradiated and nonirradiated lesion) compared to group 1. No differences were found in the rate of wound healing or collagen area. Epidermal growth was greater in the HeNe-lased area compared to unexposed tissue, but the difference was not significant. Thus, laser irradiation at 632.8 nm and 904 nm alone or in combination increased tensile strength during wound healing and may have released tissue factors into the systemic circulation that increased tensile strength on the opposite side as well.

Cyanide (CN) toxicity has recently become increasingly a clinical problem with the greater use of Laetrile for cancer treatment and of sodium nitroprusside for blood pressure control. Sodiu...

In the absence of clinical trials, positive end-expired pressure (PEEP) has been accepted as efficacious for treatment of postoperative decreases in arterial oxygen tension (FaO 2 ) from a variety of causes including adult respiratory distress syndrome (ARDS). PEEP is thought to increase PaO 2 by alveolar recruitment, which in turn, has been hypothesized to play a decisive role in pulmonary recovery One hundred and eighteen patients were followed prospectively, and after development of decreased PaO 2 , randomized to receive recruitive PEEP (determined by blood gas criteria) or supportive PEEP (the minimal PEEP required to maintain PaO 2 above 60 mm Hg on .5 inspired O 2 fraction (FIO 2 ). No prognostic factors were significantly different between the two groups. Recruitive PEEP application in 22 patients yielded a significantly increased incidence of hypotension (55 percent), pneumothorax (20 percent), and death during treatment (27 percent) when compared to the 28 supportive PEEP patients who had no hypotension or pneumothorax and only one death during treatment (4 percent). After PEEP treatment, deaths in each group were similar (19 percent and 15 percent, respectively). We find no evidence that PEEP treatment promotes beneficial outcomes and conclude that recruitment attempts may be harmful.

The role of cyanide (CN) in the mechanism of action of sodium nitroprusside (SNP) has not been well defined. Some authors consider accumulation of CN in muscle to be the principal factor responsible for resistance to SNP when given to induce hypotension. To test this hypothesis, SNP was infused in 12 anesthetized dogs. Mean aortic blood pressure was reduced 50% and dogs were maintained at this pressure for 5 minutes. After recovery, eight of the dogs (group 1) received a potassium cyanide (KCN) infusion at a rate of 0.0125 mg/kg/min for 180 minutes; the other four dogs (group 2) were given saline solution and served as controls. After 180 minutes, all 12 dogs received a second infusion of SNP in the same dose as their first. No significant differences in blood pressure or heart rate were observed between groups. Left ventricular end-diastolic pressure (LVEDP) and dP/dt were elevated following KCN; however, after the second SNP infusion these parameters decreased in both groups. Cardiac output (Qt) decreased to 55% of baseline during the first SNP infusion and showed no significant changes during the second SNP infusion, but total peripheal resistance decreased significantly during both SNP infusions. Although whole-blood CN levels and gracilis muscle tissue CN concentrations were significantly greater (p < 0.05) in group 1 after KCN, the cardiovascular effects of SNP were not significantly altered by these increases in KCN, the cardiovascular effects of SNP were not significantly altered by these increases in CN. The authors conclude that resistance to SNP in induced hypotension is not the result of direct effects of CN on smooth muscle.

Adverse cardiovascular responses to anesthesia during either electroconvulsive therapy (ECT) or elective surgical procedures were evaluated in 27 patients maintained on chronic (3 months-3 yr) monoamine oxidase inhibitor (MAOI) therapy. Changes in blood pressure and heart rate in study patients (n = 22 ECTs in 13 patients) undergoing ECT were not significantly different from those observed in patients having ECT without prior treatment with MAOIs (n = 45 ECTs in 45 patients). In both groups, blood pressure and heart rate increased significantly after ECT, but returned to baseline levels within 15 min. No complications attributable to MAOIs were observed in study patients (n = 14) undergoing elective surgical procedures. We conclude that discontinuing chronic MAOI therapy prior to anesthesia and surgery is not necessary.