The Role of Knowledge and Attitudes About Nonsteroidal Anti-inflammatory Drugs in Determining Treatment Use.

OBJECTIVE: The objective of this study was to evaluate how patient knowledge and beliefs regarding nonsteroidal anti-inflammatory drugs (NSAIDs) may influence the use of NSAIDs for osteoarthritis (OA). METHODS: Surveys of 334 adults with knee and/or hip OA were analyzed in this cross-sectional study. Familiarity with and perceptions of benefits/risks of NSAID use were measured to assess associations with the use of prescription and nonprescription oral NSAIDs. Multinomial logistic regression models were adjusted for sociodemographic and clinical variables. RESULTS: In this sample, 35.9% and 35.6% reported use of oral prescription and nonprescription-only NSAIDs, respectively. Hispanic participants, compared with non-Hispanic White participants, had lower perceived benefit (P = 0.005) and risk (P = 0.001) of prescription NSAIDs. The following were associated with prescription NSAID use instead of no NSAID use: having family/friends who used prescription (relative risk ratio [RRR] 3.91; 95% confidence interval [CI] 2.05-7.47) and over-the-counter (OTC) (RRR 3.10; 95% CI 1.65-5.83) NSAIDs for OA, understanding the consequences of using both prescription (RRR 3.50; 95% CI 1.79-6.86) and OTC (RRR 2.80; 95% CI 1.39-5.65) NSAIDs, higher perceived benefit of both prescription (RRR 2.51; 95% CI 1.71-3.66) and OTC (RRR 1.44; 95% CI 1.01-2.06) NSAIDs, and lower perceived risk of both types of NSAIDs (prescription: RRR 0.63 [95% CI 0.46-0.87]; OTC: RRR 0.53 [95% CI 0.37-0.75]). Similar results were found when we assessed the relationship between these variables and OTC NSAID use versus no oral NSAID use. CONCLUSION: Adults with knee and/or hip OA were more likely to use NSAIDs if they were more familiar with, had an increased perceived benefit of, and had a decreased perceived risk of these drugs. Patients' perceptions and beliefs about NSAIDs should be evaluated when considering them for treatment.

Target-controlled infusion of remifentanil or fentanyl during extra-corporeal shock-wave lithotripsy.

BACKGROUND AND OBJECTIVE: Target-controlled infusions (TCIs) of remifentanil and fentanyl in conscious sedation regimes for extra-corporeal shock-wave lithotripsy have not been reported. We estimated the effect site concentrations of remifentanil and fentanyl needed to obtain adequate analgesia in 50% of patients (EC50) and compared both drugs in terms of intra- and post-procedure complications. METHODS: Forty-four adult patients were randomly distributed into two groups: Group R received remifentanil and Group F received fentanyl TCI with initial effect site concentrations of 1.5 and 2 ng mL(-1), respectively. Pain was assessed using a 10-point verbal analogue scale and <3 was considered adequate analgesia. Increments or decrements of 0.5 ng mL(-1) were then introduced for subsequent patients according to Dixon's up and down method. During the rest of the procedure, TCI was adjusted to maintain verbal analogue scale <3. RESULTS: Remifentanil and fentanyl EC50 were 2.8 ng mL(-1) (95% confidence interval (CI): 1.8-3.7 ng mL(-1)) and 2.9 ng mL(-1) (95% CI: 1.7-4.1 ng mL(-1)), respectively (n.s.). At EC50, the probability of having a respiratory rate <10 was 4% (95% CI: 0-57%) for remifentanil and 56% (95% CI: 13-92%) for fentanyl. Hypoxaemia, vomiting and sedation were more frequent in Group F during and after the procedure (P < 0.05). CONCLUSIONS: A similar EC50 but more respiratory depression, sedation and PONV were found with fentanyl TCI than with remifentanil TCI.

Intramucosal gastric pH during liver transplantation.

Intramucosal gastric pH (pHi) was measured during liver transplantation in a 3-year-old girl. The basal value was below that reported as normal for paediatric patients under stable normal ventilatory and haemodynamic conditions. Additional reductions of the pHi were observed during the hepatectomy and anhepatic phase, in the absence of haemodynamic or ventilatory alterations. The reperfusion phase was characterized by a progressive return toward normal values. Because we did not measure oxygen delivery and consumption, we cannot determine whether the reduction of the pHi was due to insufficient oxygen delivery or a result of the vascular anatomical alterations due to the surgical procedure.

[Acute effect of dobutamine and amrinone on hemodynamics and splanchnic perfusion in septic shock patients]. / Efecto agudo de dobutamina y amrinona sobre la hemodinamia y perfusión esplácnica de pacientes en shock séptico.

BACKGROUND: Vasoactive drugs used in the reanimation of septic patients, can modify splanchnic perfusion. AIM: To compare the effects of dobutamine and amrinone on gastric intramucosal pH (pHi), lactate levels and hemodynamics in surgical patients with compensated septic shock. PATIENTS AND METHODS: Fourteen postoperative patients with abdominal sepsis and compensated septic shock (pHi < 7.32 or lactate > 2.5 mmol/l) were studied in a prospective, randomized, unblinded study. Patients were randomized to receive (Group 1, n = 7) dobutamine at 5 micrograms/Kg/min or (Group 2, n = 7) amrinone at 5 micrograms/Kg/min. Hemodynamic data, arterial lactate and pHi were measured before and 30, 60 and 120 minutes after starting drug infusion. RESULTS: Both drugs were associated with a decrease in lactate levels. Dobutamine infusion, but not amrinone, increased gastric pHi, as well as cardiac index and oxygen delivery. CONCLUSIONS: An improvement in gastric pHi associated with an increase in oxygen delivery, was observed with dobutamine. Amrinone showed no effect at the fixed, low dose used in the study.

Ondansetron and droperidol in the prevention of postoperative nausea and vomiting.

We have performed a prospective, randomized, double-blind clinical study to assess the efficacy of ondansetron, droperidol, or both, in preventing postoperative emesis. We studied 242 patients undergoing biliary or gynaecological surgery under general anaesthesia. Shortly before induction of anaesthesia, patients received: saline i.v. (group I, n = 62); droperidol 2.5 mg i.v. (group 2, n = 60); ondansetron 4 mg i.v. (group 3, n = 57); or droperidol 2.5 mg with ondansetron 4 mg i.v. (group 4, n = 63). Nausea occurred in 45%, 37%, 32% and 29% (P = 0.234) and vomiting in 23%, 17%, 9% and 5% (P = 0.016) of patients in groups 1, 2, 3 and 4, respectively, during the first 24 h. Groups 2 and 4 had greater sedation scores than group 1 during the first 3 h (P < 0.01). We conclude that both droperidol and ondansetron showed a significant antiemetic effect, ondansetron was not significantly better than droperidol, and the combination of droperidol and ondansetron was better than droperidol but no better than ondansetron alone.

Use of methylene blue in patients with refractory septic shock: impact on hemodynamics and gas exchange.

PURPOSE: The purpose of this study was to assess the acute effects of methylene blue, an inhibitor of nitric oxide synthesis, on hemodynamics and gas exchange in patients with refractory septic shock in a prospective clinical trial at medical and surgical intensive care units in a tertiary university hospital. PATIENTS AND METHODS: Prospective, sequential study of 10 consecutive patients admitted with severe septic shock of diverse causes and unable to achieve an adequate arterial pressure despite the use of at least two vasoactive drugs. Six of them also developed acute lung injury. All received 1 mg/kg intravenous bolus of methylene blue. Hemodynamic and respiratory parameters were measured at baseline and at 30, 60, 120, and 180 minutes after the bolus injection. RESULTS: Systolic, diastolic, mean arterial blood pressure, and systemic vascular resistance increased significantly in all patients, whereas no significant changes were observed in cardiac output, oxygen consumption, or oxygen extraction ratio. Gas exchange remained unaffected in patients with acute lung injury. CONCLUSIONS: Methylene blue had an acute vasopressor effect in patients with refractory septic shock, and it was not deleterious on respiratory function.

Epidural anaesthesia for ureteral reimplantation in an infant with congenital tracheal stenosis.

PURPOSE: We report a case of an infant with severe congenital tracheal stenosis who underwent ureteral reimplantation using lumbar epidural anaesthesia combined with light general anaesthesia. CLINICAL FEATURES: A six-month-old girl with symptomatic tracheal stenosis, demonstrated by computed tomography, was scheduled for ureteral reimplantation. She received continuous lumbar epidural anaesthesia with bupivacaine 0.25% through a 21 gauge catheter positioned at L3-4 interspace. Nitrous oxide/oxygen 50% and sevoflurane 1.5-2% were administered through a face mask and spontaneous breathing was preserved. Anaesthesia and surgery were uneventful. Postoperative epidural analgesia with bupivacaine 0.2% was excellent. The epidural catheter was withdrawn 48 hr postoperatively and she was discharged from the hospital five days later. CONCLUSION: Airway management is a major anaesthetic consideration in an infant with tracheal stenoses requiring abdominal surgery. We have demonstrated that regional anaesthesia combined with light general anaesthesia via face mask is an acceptable option, providing good analgesia during and after surgery. The technique preserves spontaneous ventilation and avoids tracheal manipulation.

[Nocturnal hypoxemia after abdominal surgery: associated factors and usefulness of oxygen therapy]. / Hipoxemia nocturna después de cirugía abdominal: factores asociados y rol de la oxigenoterapia.

BACKGROUND: Postoperative nocturnal hypoxemia (PONH) is a main factor in the genesis of respiratory, cardiac and neurologic complications after surgery. AIM: To describe the phenomenon of PONH after elective laparoscopy and laparotomy, and to evaluate the usefulness of oxygen therapy in its prevention. PATIENTS AND METHODS: Fifteen elective patients (6 M, 9 F, 51 +/- 8 years old) scheduled for laparotomy (n = 8) or laparoscopy (n = 7) were studied. Ventilatory parameters and pulse oximetry were measured pre and postoperatively. Patients were randomly assigned to receive oxygen by nasal cannula either during the first or the second postoperative night. RESULTS: PONH (SatO2 < 85) developed in seven patients (47%), of which four had undergone laparoscopic surgery. PONH was more frequent in mildly obese patients and those presenting preoperative hypoxemia (p = 0.03). Peak Flow was lower in patients presenting PONH (p = 0.04). In five patients, PONH was associated with significant tachycardia. Oxygen administration was associated with a higher SatO2 and prevented PONH in 6/7 patients. CONCLUSIONS: PONH is a common event in patients older than 40 years scheduled for open or laparoscopic abdominal surgery, and develops more frequently in those with preoperative nocturnal hypoxemia and greater ventilatory impairment. PONH can be prevented, most of the time, with oxygen administration.

[Patients with acute adult respiratory distress syndrome: effects of inhaled nitric oxide on gas exchange and hemodynamics]. / Pacientes con síndrome de distress respiratorio agudo del adulto: efectos del óxido nítrico inhalado sobre el intercambio gaseoso y la hemodinamia.

BACKGROUND: Adult respiratory distress syndrome is highly prevalent in intensive care units and has a high mortality. Lately, nitric oxide has been used as adjuvant therapy. AIM: To study the effects of nitric oxide inhalation in patients with adult respiratory distress syndrome. PATIENTS AND METHODS: Twelve patients with adult respiratory distress syndrome, were subjected to nitric oxide inhalation at a concentration of 10 parts per million, during 30 minutes. RESULTS: At the end of the nitric oxide inhalation period, there was an improvement of PaO2/FIO2 ratio from 89 +/- 32 to 111 +/- 43 mm Hg and a 16% reduction of lung shunting (Qs/Qt). CONCLUSIONS: Nitric oxide inhalation at a concentration of 10 parts per million improved arterial oxygenation and reduced pulmonary shunting in patients with adult respiratory distress syndrome.

[Inhibition of the nitric oxide pathway in refractory septic shock]. / Inhibición de la vía del óxido nítrico en el shock séptico refractario.

AIM: To assess the acute effects of methylene blue infusion, an inhibitor of nitric oxide synthesis, on hemodynamic parameters in patients with refractory septic shock. PATIENTS AND METHODS: Fourteen patients admitted to intensive care units with septic shock of diverse etiologies and unable to maintain median arterial pressures over 60 mm Hg with the use of at least 2 vasoactive drugs, were studied. All received a 1 mg/kg bolus of methylene blue Hemodynamic parameters were measured before and 30, 60, 120 and 180 min after the bolus. RESULTS: Systolic and diastolic blood pressure and systemic vascular resistance increased in all patients. There were no significant changes in cardiac output, oxygen consumption or extraction. CONCLUSIONS: Methylene blue has an acute pressor effect in patients with septic shock.

[The imperative of medical involvement in the implementation of quality control systems]. / El imperativo de la participación médica en la implementación de sistemas de control de calidad.

Changes in health care delivery in Chile over the last years include rising costs and the relative increase of prepaid private insurance programs. It is expected that there will be increasing pressures on health providers to decrease cost while maintaining or improving quality. A series of common clinical problems are reviewed (hernia repair, appendicitis, gallstone disease, trauma, preoperative evaluation) to demonstrate that using a scientific method-continuous quality improvement- and considering the local socioeconomic reality, this challenge can be met. Emphasis is made on the need for physicians to participate in such a process and on the teaching of these concepts. Medical societies and schools should consider these health care developments and adopt to this changes.

[Prolonged inhalation of nitric oxide in adult respiratory distress syndrome in a case]. / Inhalación prolongada de óxido nítrico en el distress respiratorio agudo del adulto en un caso.

Inhalation therapy with nitric oxide has been suggested as beneficial in the adult respiratory distress syndrome, however there are few reports of its prolonged use. We report a patient with a chronic lymphocytic leukemia that developed an adult respiratory distress syndrome with severe hypoxemia, refractory to conventional therapeutic measures, during the course of a septic shock. The patient received nitric oxide (19 ppm) improving arterial oxygen saturation and allowing the reduction of FiO2 to 40%. The patient died five days later due to a multiple organ failure.

[Morphine infusion for postoperative pain management in patients who have undergone upper abdominal surgery]. / Infusión de morfina para el manejo del dolor postoperatorio en pacientes sometidos a cirugía abdominal alta.

We compared the efficacy and side effects of postoperative continuous infusions versus intermittent intravenous on-demand morphine, with or without the addition of clonixin. Eighty five healthy patients, aged 18 to 65 years, scheduled for elective cholecystectomy, were prospectively randomized: Group 1 (n = 22) received morphine 2.5 mg i.v. on-demand; group 2 (n = 22) received a clonixin 400 mg/day i.v. infusion; group 3 (n = 19) a morphine 0.4 mg/kg/day i.v. infusion; and group 4 (n = 22) received a clonixin 400 mg/day plus a morphine 0.4 mg/kg/day i.v. infusion. Groups 2, 3 and 4 also received, on-demand, 2.5 mg i.v. bolus doses of morphine. A blind observer recorder analogue and descriptive pain scores, respiratory rates and side-effects for 72 hours postoperatively. Groups with morphine infusions had less overall pain scores for the first day when compared with intermittent dosing (p < 0.05); these groups also had less pain during the night (p = 0.0016) and required less additional morphine (p < 0.0001). Side-effects were similar and no cases of heavy sedation or respiratory depression were observed. We conclude that a morphine 0.4 mg/kg/day infusion is a safe and effective alternative to on demand dosing in healthy patients after elective cholecystectomy, achieving better analgesia without increasing side-effects. Clonixin 400 mg/day seems to add no significant benefits.

Direction of catheter insertion and incidence of paresthesias and failure rate in continuous epidural anesthesia: a comparison of cephalad and caudad catheter insertion.

BACKGROUND AND OBJECTIVES: Paresthesias and unblocked segments during continuous epidural anesthesia--sometimes leading to higher doses of local anesthetics--can increase the risk of this technique. A cephalad insertion of the epidural catheter might decrease the incidence of these problems, but this has not been evaluated before in a controlled study. METHODS: In a prospective, double-blind, randomized study, we compared the incidence of paresthesias during catheter insertion and the failure rate of continuous epidural anesthesia in two groups of obstetric patients. In group 1 (n = 52), the Tuohy needle bevel was directed cephalad during catheter insertion. In group 2 (n = 53), it was directed caudad. The catheter was introduced 4-5 cm into the epidural space, and bupivacaine 25 mg plus fentanyl 50 micrograms were administered through it. RESULTS: Twenty percent of the patients in group 1 had paresthesias versus 40% in group 2 (p = 0.0249; 95% confidence interval of the difference 1-40%); intensity of paresthesias was greater in group 2. Pain relief was complete in 75% and 80% of the patients in groups 1 and 2, respectively (NS); three patients in group 1 and one in group 2 had unblocked segments (NS). CONCLUSIONS: Our results support the contention that the catheter should be directed cephalad during insertion for continuous epidural anesthesia.

Should supraclavicular brachial plexus block be avoided in pregnancy?

Unilateral phrenic nerve block is common after supraclavicular brachial plexus block techniques, although it is rarely symptomatic in patients without respiratory disease. A 24-weeks-pregnant woman was scheduled for a carpal tunnel release because of intractable pain. After a perivascular subclavian brachial plexus block with 30 ml of 0.33% plain bupivacaine was performed, the patient developed a right phrenic nerve block manifested by acute dyspnea and cough. No deleterious consequences followed, but surgery was canceled. Respiratory changes produced by pregnancy might compromise ventilatory reserve. Thus, we suggest avoiding supraclavicular approaches to brachial plexus block in pregnant women, since they may be as prone to developing respiratory embarrassment, secondary to phrenic block, as patients with pulmonary pathology.

Benzodiazepine premedication causes hypoxemia during spinal anesthesia in geriatric patients.

BACKGROUND AND OBJECTIVES: The use of sedatives during regional anesthesia can lead to life-threatening hypoxemia. Older patients particularly are prone to enhanced effects of these drugs. We studies whether oral premedication with benzodiazepines produced hypoxemia during spinal anesthesia in elderly patients. METHODS: In a prospective, double-blind, and randomized study, we evaluated the effect of oral benzodiazepine premedication on the incidence of hypoxemia measured by pulse oximetry (arterial oxygen saturation less than 90% for 30 seconds or longer) during surgery under spinal anesthesia in 80 geriatric patients divided into four equal groups: 1, control, no premedication; 2, 1 mg flunitrazepam; 3, 1 mg lorazepam; and 4, 7.5 mg midazolam. RESULTS: The incidence of hypoxemia in the four groups was: 1, 15%; 2, 45%; 3, 20%; and 4, 60% (p = 0.0078); overall incidence was 42% in premedicated patients versus 15% in unpremedicated controls (p = 0.0304). Seventy-four percent of patients who presented drowsiness and anesthetic level above T7 had desaturation compared to only 7% of those who were awake and had lower level (p less than 0.0005). No association between hypoxemia and other factors (age, weight, ASA physical status, and position during surgery) was found. All the episodes of desaturation were easily corrected with low supplemental oxygen concentrations. CONCLUSIONS: Premedication with oral benzodiazepines may produce hypoxemia during spinal anesthesia in elderly patients. Lorazepam appeared safer than flunitrazepam and midazolam. Monitoring of arterial blood oxygen saturation and/or supplemental oxygen is mandatory in geriatric patients with high spinal anesthetic level and/or drowsiness during surgery.

Trigeminal nerve block as a complication of epidural anesthesia.

BACKGROUND AND METHODS: A healthy pregnant woman underwent labor under successful epidural analgesia with a total drug mass of 100 mg plain bupivacaine plus 100 micrograms fentanyl in three doses given over 150 minutes. RESULTS: Ninety minutes after the last dose, she developed signs and symptoms of a left trigeminal nerve block along with an ipsilateral Horner's syndrome. The cutaneous anesthesia level reached C6 on the left and T6 on the right side. Neurologic symptoms disappeared four hours later. CONCLUSION: An excessive upward epidural extension of bupivacaine block, reaching the trigeminal spinal nucleus and/or tract in the cervical spinal cord, is postulated.