Biomedical subjects
Publications and source records attributed to P Sporn.
A patient with Parkinson's disease refused both anti-Parkinson medication and general anaesthesia. Low dose remifentanil infusion suppressed her otherwise severe tremor, and the operation was performed uneventfully under local anaesthesia.
PURPOSE: To describe the prolonged effect of the intermediate-acting, non-depolarising neuromuscular blocking agents rocuronium and atracurium in a 29-yr-old apparently healthy woman. CLINICAL FEATURES: Because of abdominal pain the patient was scheduled for explorative laparoscopic pelvic examination. General anaesthesia was induced with fentanyl, midazolam and propofol. Muscle relaxation was achieved with 0.6 mg.kg-1 rocuronium. Anaesthesia was maintained with nitrous oxide and propofol. Two Hz train-of-four stimulation every 15 sec evoked no twitch responses until 60 min after rocuronium. Further relaxation was achieved with 0.075 mg.kg-1 atracurium after which twitch responses recurred after 45 min. Fifteen minutes later neuromuscular blockade was successfully reversed with atropine and neostigmine. The postanaesthetic course was uneventful. Because of the increased sensitivity to rocuronium and atracurium the patient was re-evaluated postoperatively. History revealed occasional double vision, fatigue, muscle cramps, stiffness and myoglobinuria. Clinical neurological examination showed ptosis, tremor, ataxia and bradydiadochokinesia. A standardised lactate stress testing on a bicycle was pathological and, after muscle biopsy, the diagnosis of mitochondrial myopathy was established. CONCLUSION: An increased sensitivity to rocuronium and atracurium may occur in patients with mitochondrial myopathy. In these patients appropriate dosing of muscle relaxants and adequate monitoring of the neuromuscular blockade are required. If an increased sensitivity to rocuronium and atracurium occurs in an apparently healthy subject, further neurological investigations should follow.
OBJECTIVE: To determine the effect of reoperation for severe abdominal sepsis on the course of proinflammatory mediators and hemodynamic factors. DESIGN: Inception cohort. SETTING: A university hospital and a secondary care hospital. PATIENTS AND METHODS: Fifteen patients suffering from severe peritonitis due to intestinal perforation or infected necrotizing pancreatitis were studied following 19 subsequent operations. Plasma samples were obtained immediately before and after reoperation, as well as at 1, 3, 6, 12, and 24 hours after operation to determine endotoxin, tumor necrosis factor alpha, and interleukin-6 levels. Clinical factors and therapeutic support were recorded at the corresponding times. MAIN OUTCOME MEASURES: Postoperative hemodynamic instability as defined by changes of the mean arterial pressure, pulmonary capillary wedge pressure, and vasopressor support. Courses of proinflammatory mediators were correlated to the hemodynamic findings. RESULTS: Mean arterial pressure decreased from 94 mm Hg postoperatively to 80 mm Hg at 3 hours (P = .006) and 81 mm Hg at 6 hours postoperatively (P = .005). Pulmonary capillary wedge pressure dropped from 14 mm Hg postoperatively to 12 mm Hg at 1 hour (P = .05). Vasopressor support significantly increased from 1 to 6 hours postoperatively (P = .02). Neither endotoxin nor tumor necrosis factor alpha levels showed significant changes in the postoperative course. Interleukin-6 levels continously increased from 586 pg/mL preoperatively to 910 pg/mL at 1 hour (P = .02) and 931 pg/mL at 3 hours postoperatively (P = .04). Overall interleukin-6 levels (R = -0.38, P = .003) and especially early postoperative interleukin-6 levels inversely correlated with postoperative mean arterial pressure. CONCLUSIONS: Reoperation for abdominal sepsis frequently causes substantial hypotension, and is, thus, potentially harmful to the patient. Reoperative trauma may induce an early postoperative increase in interleukin-6 levels. Because this increase occurs before the development of hypotension, a relationship between the kinetics of this cytokine and the observed hemodynamic instability may be present.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
OBJECTIVE: To investigate the effect of norepinephrine (NE) on hemodynamics, oxygen metabolism and renal function in patients with severe septic shock. DESIGN: Prospective study. SETTING: Post-operative ICU in a municipal general hospital. PATIENTS: The study included 56 patients with extreme low resistance states due to abdominal sepsis, who remained hypertensive (MAP < 60 mmHg) despite optimal fluid therapy and dopamine > 20 micrograms/kg/min and cumulative doses of dopamine and dobutamine > 30 micrograms/kg/min, respectively. INTERVENTIONS: After registration of baseline values dopamine was reduced to 2.5 micrograms/kg/min, and norepinephrine was administered starting at a dose of 0.05 micrograms/kg/min until a mean arterial pressure of more than 60 mmHg could be maintained. MEASUREMENTS AND RESULTS: During norepinephrine infusion (dosage ranging between 0.1-2 micrograms/kg/min, mean dose rate: 0.4 micrograms/kg/min) mean arterial pressure and systemic vascular resistance index increased significantly (p < 0.001). After 8 h a significant increase in stroke volume (p < 0.05) and decrease in heart rate (p < 0.05) could be observed. There was no significant change in cardiac index (CI), oxygen delivery (O2AVI) and oxygen consumption (VO2I). Creatinine clearance increased significantly (p < 0.005) from a control value of 75 +/- 37 ml/min to 102 +/- 43 ml/min after 48 h NE-treatment. CONCLUSION: Our results suggest that norepinephrine can be used safely in the treatment of severe septic shock states. Mean arterial pressure and glomerular filtration rate improved markedly without deleterious effects on CI, O2AVI and VO2I.
Explore the source record for details and available documents.
The aim of our study was to evaluate the clinical usefulness of a monoclonal antibody (MAB; BW 250/183; Behringwerke, Germany) in patients with suspected perioperative septic foci. The MAB is directed against the nonspecific crossreacting antigen (NCA 95) which has been found on the surface of human neutrophil granulocytes and which represents a murine immunoglobulin isotype of IgG1. Immunoscintigraphy was performed by labelling the MAB with 740 MBq (20mCi) Tc-99m. Data acquisition followed 4 and 18 to 24 hours after administration by a digital Anger camera (APEX 409A, Elscint). 53 patients were investigated (31 female, 22 male; average age 39 years), 4 patients were twice, 1 patient was 3 times evaluated, which results in a total of 59 studies. 45 patients experienced operation within 12 hours after our investigation, which resulted in 36 true positive, 5 true negative, 3 false negative, and 1 false positive findings. This means a sensitivity of 92%, and specificity of 83%. Immunoscintigraphy with granulocyte antibodies can be performed at any time, the preparation of the radiopharmaceutical is simple, the image quality is high; the obtained information concerning localization and size of perioperative septic infections permits the determination of the optimal point of time for surgical intervention. The accumulation of activity was visible as early as 4 hours post application. SPECT would enhance the diagnostic accuracy, but this technique cannot be applied in all such patients.
Explore the source record for details and available documents.
Muscle biopsy and in vitro contracture tests for diagnosis of susceptibility to malignant hyperthermia (MH) were performed in two patients who had developed fever and severe myolysis during exercise. MH susceptibility was confirmed in one patient, but in the other, exercise-induced heat stroke proved to be the correct diagnosis. Clinical presentation and epidemiology of exercise-induced MH and its relation to the heat stroke syndrome are discussed.
Explore the source record for details and available documents.
Hydromineral metabolism and serum arginine-vasopressin (AVP) levels were investigated in 11 patients who sustained brain death. They showed various degrees of polyuria with low osmolality and low fractional sodium excretion. Urine osmolality was always below that of serum, and AVP levels were between 1.3 and 50.0 pg/ml vs 0.7-8.0 pg/ml in ten normal subjects. Thus central diabetes insipidus was excluded. A renal mechanism inducing water diuresis has to be assumed. The type of renal lesion, however, remains unclear.
The anaesthetic records of 61 patients who had experienced adverse reactions thought to be malignant hyperthermia (MH) were reviewed retrospectively to evaluate the diagnostic importance of clinical symptoms. Using the in vitro contracture test, 38 (62%) patients were identified as MH susceptible (MHS), the remainder showing normal test results (MHN). Generalized rigidity, ventricular arrhythmias, cyanosis and postoperative myoglobinuria were observed significantly more often in MHS patients. Median values of body temperature and creatine kinase serum concentrations were significantly greater in the MHS group. Masseter spasm and sinus tachycardia were as common in MHS as in MHN individuals. Statistical models using generalized rigidity, ventricular arrhythmias, cyanosis and fever exceeding 38 degrees C for prediction of MH showed a maximum sensitivity and specificity of 78% and thus are not acceptable for clinical use. For definitive diagnosis of MH, the well established in vitro contracture test remains essential.
The intra- and postoperative course of 30 anaesthetics in 24 MH-carriers verified by in vitro contracture tests is reported. None of the patients received dantrolene prophylactically and only agents known to be nontriggers were used for anaesthesia. Neither MH-related changes in perioperative heart rates, body temperatures, and CK levels nor any other symptoms of MH were observed. We conclude that the prophylactic use of dantrolene is not necessary in patients suspected to be prone to MH if triggering agents are avoided and the patients are closely monitored.
The intra- and postoperative course of 30 general and 3 regional anesthetics in 27 MH-carriers verified by in vitro contracture tests is reported. None of the patients received dantrolene prophylactically. Disposable tubings were used for ventilation, vaporizers and soda lime were removed. ECG, esophageal temperature, blood pressure, oxygen saturation, and end tidal pCO2 were monitored. Minor tranquilizers were offered for premedication. Fentanyl, thiopentone, nitrous oxide, non depolarizing relaxants, neuromuscular antagonists and naloxone were used. In three patients, surgery was performed during epidural or spinal anesthesia with the use of amide local anesthetics. Neither MH-related changes in perioperative heart rates, body temperatures, and CK levels nor any other symptoms of MH were observed in any patient. The anesthetic techniques used seem to be safe and reliable; the anesthetic management of known MHS patients is discussed in detail.
We investigated the impact of norepinephrine administration on hemodynamics, oxygen metabolism and renal function in patients in severe septic shock. PATIENTS AND METHODS. Twenty-six patients with extremely low resistance who were between 24 and 87 years of age were included in the study. In 7 patients, acute necrotizing pancreatitis and superinfection was diagnosed; 19 patients suffered from diffuse peritonitis. The entrance criteria for the study were: a mean arterial pressure (MAP) of below 60 torr or, in chronic hypertensive patients, a decrease in systolic pressure of more than 50 torr compared to previous values, despite volume optimization, and dopamine greater than 20 micrograms/kg per min and cumulative doses of dopamine/dobutamine greater than 30 micrograms/kg per min, respectively. Cases with tachycardia greater than 140/min were also included in the study even when the inotropic medication dose was lower. After registration of baseline values, dopamine was reduced to 2.5 micrograms/kg per min, and norepinephrine was administered starting at a dose rate of 0.05 micrograms/kg per min, until a MAP of greater than 60 torr could be maintained. RESULTS. Of the 26 patients investigated, 16 survived; 10 patients with persisting sepsis died due to multiple organ failure (mortality: 38.5%). During the study period, a norepinephrine dosage ranging between 0.1 and 2 micrograms/kg per min was necessary to stabilize the arterial pressure. The mean dose rate was 0.3 micrograms/kg per min. The mean arterial pressure and systemic vascular resistance index showed a statistically significant increase of 30 and 20%, respectively, just after 1 h and distinctly remained above the initial values in the further course. The cardiac index remained constant or increased slightly. After 24 h a statistically significant increase in stroke volume and a decrease in heart rate could be observed. Creatinine clearance increased significantly from the control value of 73 +/- 48 ml/min to 114 +/- 37 ml/min after 48 h under norepinephrine treatment. O2-delivery and O2-consumption did not change significantly, although they showed a slight tendency to increase. CONCLUSION. When patients are in a septic high output-low resistance condition, particular attention must be paid to maintaining sufficient mean arterial pressures. Our results suggest that this essential goal can be achieved by norepinephrine. The mean arterial pressure and glomerular filtration rate improved markedly, and there was no evidence of bad effects such as an increased afterload on critical parameters like cardiac index, O2-delivery and O2-consumption.
Explore the source record for details and available documents.
We investigated the effect of large volume replacement with balanced electrolyte solutions on extravascular lung water (EVLW) in 16 adult surgical patients with sepsis syndrome. Patients entered the study within the 24 h period following surgical interventions for acute necrotizing pancreatitis, intra-abdominal abscesses, and/or peritonitis. Sequential measurements (n = 108) were made at intervals of 6-12 h over a 48 h period. There were no significant differences between initial and final values of thermal-dye EVLW (5.0 +/- 1.1 vs. 5.7 +/- 1.1 ml/kg), plasma colloid osmotic pressure (COP, 13.3 +/- 2.5 vs. 13.2 +/- 2.9 mmHg), pulmonary artery wedge pressure (PAWP, 9.2 +/- 3.0 vs. 10.8 +/- 3.0 mmHg), and COP-PAWP gradient (4.0 +/- 3.5 vs. 2.4 +/- 3.9 mmHg). All results expressed as (mean +/- SD). The EVLW did not correlate with plasma COP, PAWP, or COP-PAWP gradient. We conclude that large volume replacement with balanced electrolyte solutions with the secondary decrease in plasma COP and COP-PAWP gradient do not necessarily contribute to a substantial increase in EVLW. This study fails to show any causal relationship between decrease in plasma COP or COP-PAWP gradient and oedema formation in the lung.