The effect of placement and management of intrathecal catheters following accidental dural puncture on the incidence of postdural puncture headache and severity: a retrospective real-world study

Accidental dural puncture during an attempt to establish labour epidural analgesia can result in postdural puncture headache and long-term debilitating conditions. Epidural blood patch, the gold standard treatment for this headache, is invasive and not always successful. Inserting an intrathecal catheter after accidental dural puncture may prevent postdural puncture headache. We evaluated the effect of intrathecal catheter insertion on the incidence of postdural puncture headache and the need for epidural blood patch and whether duration of intrathecal catheterisation or injection of intrathecal saline affected outcome. Our retrospective study was conducted at two tertiary, university-affiliated medical centres between 2017 and 2022 and included 92,651 epidurals and 550 cases of accidental dural puncture (0.59%); 219 parturients (39.8%) received an intrathecal catheter and 331 (60.2%) a resited epidural. Use of an intrathecal catheter versus resiting the epidural did not decrease the odds of postdural puncture headache, adjusted odds ratio (aOR) (95%CI) 0.91 (0.81-1.01), but was associated with a lower need for epidural blood patch (aOR (95%CI) 0.82 (0.73-0.91), p < 0.001). We found no benefit in leaving in the intrathecal catheter for 24 h postpartum (postdural puncture headache, aOR (95%CI) 1.01 (1.00-1.02), p = 0.015; epidural blood patch, aOR (95%CI) 1.00 (0.99-1.01), p = 0.40). We found an added benefit of injecting intrathecal saline as it decreased the incidence of postdural puncture headache (aOR (95%CI) 0.85 (0.73-0.99), p = 0.04) and the need for epidural blood patch (aOR (95%CI) 0.75 (0.64-0.87), p < 0.001). Our study confirms the benefits of intrathecal catheterisation and provides guidance on how to best manage an intrathecal catheter.

Preoperative sleep quality predicts postoperative pain after planned caesarean delivery

BACKGROUND

Severe post-caesarean pain remains an important issue associated with persistent pain and postpartum depression. Women's sleep quality prior to caesarean delivery and its influence on postoperative pain and analgesic intake have not been evaluated yet.

METHODS

Women undergoing caesarean delivery with spinal anaesthesia (bupivacaine 12 mg, fentanyl 20 μg, morphine 100 μg) were evaluated preoperatively for sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire (PSQI 0-5 indicating good sleep quality, PSQI 6-21 poor sleep quality). Peak and average postoperative pain scores at rest, movement and uterine cramping were evaluated during 24 h using a verbal numerical pain score (VNPS; 0 indicating no pain and 100 indicating worst pain imaginable), and analgesic intake was recorded. Primary outcome was peak pain upon movement during the first 24 h.

RESULTS

Seventy-eight of 245 women reported good sleep quality (31.2%; average PSQI 3.5 ± 1.2) and 167 poor sleep quality (68.2%; average PSQI 16.0 ± 3.4; p < 0.001). Women with poor sleep quality had significantly higher peak pain scores upon movement (46.7 ± 28.8 vs. 36.2 ± 25.6, respectively; p = 0.006). With multivariable logistic regression analysis, poor sleep quality significantly increased the risk for severe peak pain upon movement (VNPS ≥70; OR 2.64; 95% CI 1.2-6.0; p = 0.02).

DISCUSSION

A significant proportion of women scheduled for caesarean delivery were identified preoperatively as having poor sleep quality, which was associated with more severe pain and increased analgesic intake after delivery. The PSQI score may therefore be a useful tool to predict increased risk for acute post-caesarean pain and higher analgesic requirements, and help tailor anaesthetic management.

SIGNIFICANCE

Multiple studies have evaluated predictors for severe acute pain after caesarean delivery that may be performed in a clinical setting, however, sleep quality prior to delivery has not been included in predictive models for post-caesarean pain. The PSQI questionnaire, a simple test to administer preoperatively, identified that up to 70% of women report poor sleep quality before delivery, and poor sleep quality was associated with increased post-caesarean pain scores and analgesic intake, indicating that PSQI could help identify preoperatively women at risk for severe pain after caesarean delivery.

Peripartum anesthetic management of renal transplant patients--a multicenter cohort study

As the number and success of renal transplantation has grown, there has been an increase in the number of renal transplant patients giving birth. To date, there has been no data on obstetric anesthesia management of these patients. The purpose of this study was to build an Israeli national database on parturients after renal transplant. A sixteen-year (calendar years 1996-2011) retrospective study was conducted at three major tertiary centers with a combined current birth rate of approximately 25,000 deliveries annually. We found 83 labors in 64 women. Forty-two percent of this population suffered from hypertension while 12.5% had diabetes. Forty-seven percent of women had a vaginal delivery while 53% of women had a cesarean section. The rate of epidural analgesia for labor was 59%, and rate of regional anesthesia during cesarean section was 75%. There were no anesthetic complications in any cases. Standard ASA monitoring was used in all cases except for one woman with severe hypertension who required an arterial line during her cesarean section. Forty-seven percent of newborn were under 37 weeks with average gestational week 36 ± 3 days and birth weight 2.5 ± 0.7 kg. Average Apgar was 8.4 ± 1.3 at one minute and 9.3 ± 0.7 at five minutes. There was one neonatal death in the CS group due to placental abruption. Patients after renal transplant can safely undergo birth and obstetric analgesia.

Risk factors for failure to extend labor epidural analgesia to epidural anesthesia for Cesarean section

OBJECTIVE

To identify parturients at risk of inability to extend labor epidural analgesia in whom alternative methods of anesthesia should be considered for Cesarean section (CS).

METHODS

For 6 months, we prospectively studied women undergoing a CS with a functioning epidural catheter in place from the delivery ward. All parturients received the same epidural protocol: bolus of bupivacaine 0.1% and fentanyl, then bupivacaine 0.1% and fentanyl (2 microg/ml) 10-15 ml/h and an additional 5 ml of bupivacaine 0.125% top-ups according to patient request. Sixteen millilitres of lidocaine 2%, 1 ml of bicarbonate, and 100 microg of fentanyl were given for CS. Failed epidural analgesia was defined as the need to convert to general anesthesia.

RESULTS

Of the 101 parturients studied, 20 (19.8%) required conversion to general anesthesia. In univariate analysis, the likelihood of failed epidural anesthesia was inversely correlated with parturient's age (P = 0.014) and directly correlated with pre-pregnancy weight (P = 0.019), weight at the end of pregnancy (P = 0.003), body mass index (BMI) at the end of pregnancy (P = 0.0004), gestational week (P = 0.008), number of top-ups (P = 0.0004) and visual analog scale (VAS) 2 h before CS (P = 0.03). In multivariate analysis, the number of top-ups in the delivery ward was the best predictor of epidural anesthesia failure (odds ratio 4.39, P = 0.005).

CONCLUSION

Younger, more obese parturients at a higher gestational week, requiring more top-ups during labor, having a higher VAS in the 2 h before CS are at risk of inability to extend labor epidural analgesia to epidural anesthesia for CS.

Risk factors for failure to extend labor epidural analgesia to epidural anesthesia for Cesarean section

AIM

To identify parturients at risk of inability to extend labor epidural analgesia in whom alternative methods of anesthesia should be considered for Cesarean section (CS).

METHODS

For 6 months, we prospectively studied women undergoing CS with a functioning epidural catheter in place from the delivery ward. All parturients received the same epidural protocol: bolus of bupivacaine 0.1% and fentanyl, followed by bupivacaine 0.1% and fentanyl (2 microg/ml) 10-15 ml/h and an additional 5 ml of bupivacaine 0.125% as top-up according to patient request. Sixteen milliliters of lidocaine 2%, 1 ml of bicarbonate and 100 microg of fentanyl were given for CS. Failed epidural analgesia was defined as the need to convert to general anesthesia.

RESULTS

Of the 101 parturients studied, 20 (19.8%) required conversion to general anesthesia. In univariate analysis, the likelihood of failed epidural anesthesia was inversely correlated with parturient age (P = 0.014) and directly correlated with pre-pregnancy weight (P = 0.019), weight at the end of pregnancy (P = 0.003), body mass index at the end of pregnancy (P = 0.0004), gestational week (P = 0.008), number of top-ups (P = 0.0004) and visual analog scale (VAS) score 2 h before CS (P = 0.03). In multivariate analysis, the number of top-ups in the delivery ward was the best predictor of epidural anesthesia failure (odds ratio, 4.39; P = 0.005).

CONCLUSION

Younger, more obese parturients at a higher gestational week, requiring more top-ups during labor and having a higher VAS score in the 2 h before CS are at risk for inability to extend labor epidural analgesia to epidural anesthesia for CS.

Nausea and vomiting after fast-track cardiac anaesthesia

BACKGROUND

The aim of this study was to determine the prevalence of postoperative nausea and vomiting (PONV) after fast-track cardiac anaesthesia, risk factors for PONV and its influence on the length of stay in the intensive care unit (ICU).

METHODS

A prospective study was performed in the cardiothoracic ICU (CTICU) of a university hospital; 1221 consecutive patients undergoing fast-track anaesthesia (FTCA) in cardiac surgery were enrolled in the study. Severity of PONV was assessed immediately after extubation and then every hour until discharge from the CTICU. Metoclopramide 10 mg i.v. was used as a first-line rescue medication and ondansetron 4 mg i.v. as second-line rescue medication for PONV.

RESULTS

Nausea was reported in 240 (19.7%) patients, and vomiting in 53 (4.3%). A total of 269 (22%) patients were treated with metoclopramide and 38 (3.1%) with metoclopramide and ondansetron. The latter was effective in all cases. Risk factors for PONV were age less than 60 yr, female gender and previous history of PONV. Discharge from the CTICU was delayed for a few hours because of PONV in eight patients, all of whom were discharged the same day.

CONCLUSIONS

The incidence of PONV is relatively low after FTCA and does not prolong ICU stay. Prophylactic administration of anti-emetic drugs before FTCA is not necessary.

Computer assisted physiologic monitoring and stability assessment in vascular surgical patients undergoing general anesthesia--preliminary data

BACKGROUND

Physiologic monitors present an influx of numerical data that can be overwhelming to the clinician. We combined several parameters in an effort to reduce the amount of information that must be continuously monitored including oxyhemoglobin saturation by pulse oximetry, end-tidal CO2 concentration, arterial blood pressure, and heart rate into an integrated measure--the health stability magnitude (HSM). The HSM is computed for a predetermined basal period, the reference HSM (RHSM), and recalculated continuously for comparison with the baseline value. In this study we present the HSM concept and examine changes in the HSM during abdominal aortic aneurysm surgery.

MATERIALS AND METHODS

After IRB approval, nine patients were studied. The anesthesiologist recorded all significant intra-operative events. Within a defined time interval, data were recorded and used to calculate a combined parameter, the HSM. The baseline or reference value of this index (RHSM) was calculated after the induction of anesthesia. Individual HSM values were repeatedly calculated for ten second periods after the RHSM value was established. A > 30% deviation of the HSM from the RHSM was considered significant. Deviations in the HSM were compared with events recorded by the anesthesiologist on a paper record and with the record from an electronic record-keeping system. The deviation observed between two consecutive HSMs, called dHSM, was plotted against HSM to construct a contour diagram of data from all patients to which individual cases could be compared.

RESULTS

The plot showed that dHSM vs. HSM values were tightly clustered. The inner contour on the distribution plot contained 90% of values. Individual patient's time course, projected on this diagram, revealed deviations form "normal" physiology. Fifty-nine events led to > 30% deviations in the HSM; 27 were anticipated events and 32 were unanticipated.

CONCLUSION

The correlation between HSM and dHSM depicts changes in multiple monitored parameters that can be viewed using a single graphical representation. Projection of individual cases on the contour diagram may help the clinician to distinguish relative intraoperative stability from important events. Data reduction in this manner may guide clinical decision-making in response to unanticipated or unrecognized events.

Laparoscopic extraperitoneal inguinal hernia repair with spinal anesthesia and nitrous oxide insufflation

BACKGROUND

Laparoscopic repair of inguinal hernia is traditionally performed under general anesthesia mainly because of the adverse effects that carbon dioxide pneumoperitoneum has on awake patients. Since a mandatory use of general anesthesia for all hernia repairs is questionable, the feasibility of laparoscopic extraperitoneal herniorraphy using spinal anesthesia combined with nitrous oxide insufflation was investigated.

METHODS

Over a 4-month period, February to May 1998, we performed 35 consecutive total extraperitoneal inguinal hernia procedures (24 unilateral, 11 bilateral) using spinal anesthesia and nitrous oxide extraperitoneal gas. Data on operative findings, self-reported operative and postoperative pain and discomfort (visual analog pain scale), procedure-related hemodynamics, and complications were collected prospectively.

RESULTS

All 35 procedures were completed laparoscopically without the need to convert to general anesthesia. Mean operative time was 39 +/- 7 min for unilateral hernia and 65 +/- 10 min for bilateral hernia. Incidental peritoneal tears occurred in 22 patients (63%) resulting in nitrous oxide pneumoperitoneum, which was well tolerated. The patients remained hemodynamically stable throughout the procedure, and operative conditions and visibility were excellent. Complications at a mean of 4 months after the procedure included seven uninfected seromas (20%), three patients with transient testicular pain, and one (3%) recurrence.

CONCLUSIONS

Laparoscopic total extraperitoneal hernia repair can be safely and comfortably performed using spinal anesthesia with extraperitoneal nitrous oxide insufflation gas. This method provides a good alternative to general anesthesia.

Evaluation of triage decisions for intensive care admission

OBJECTIVE

To assess physician decision-making in triage for intensive care and how judgments impact on patient survival.

DESIGN

Prospective, descriptive study.

SETTING

General intensive care unit, university medical center.

INTERVENTIONS

All patients triaged for admission to a general intensive care unit were studied. Information was collected for the patient's age, diagnoses, surgical status, admission purpose, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and mortality. The number of available beds at the time of triage and reasons for refused admission were obtained.

MEASUREMENTS AND MAIN RESULTS

Of 382 patients, 290 were admitted, 92 (24%) were refused admission, and 31 were admitted at a later time. Differences between admission diagnoses were found between patients admitted or not admitted (p < .001). Patients refused admission had higher APACHE II scores (15.6+/-1.5 admitted later and 15.8+/-1.4 never admitted) than did admitted patients (12.1+/-.4; p < .001). The frequency of admitting patients decreased when the intensive care unit was full (p < .001). Multivariate analysis revealed that triage to intensive care correlated with age, a full unit, surgical status, and diagnoses. Hospital mortality was lower in admitted (14%) than in refused patients (36% admitted later and 46% never admitted; p < .01) and in admitted patients with APACHE II scores of 11 to 20 (p = .02). The 28-day survival of patients was greater for admitted patients compared with patients never admitted (p = .01).

CONCLUSIONS

Physicians triage patients to intensive care based on the number of beds available, the admission diagnosis, severity of disease, age, and operative status. Admitting patients to intensive care is associated with a lower mortality rate, especially in patients with APACHE scores of 11 to 20.

Pulse oximetry plethysmographic waveform during changes in blood volume

Systolic pressure variation (SPV) and its dDown component have been shown to be sensitive factors in estimating intravascular volume in patients undergoing mechanical ventilation. In this study, ventilation-induced changes in pulse oximeter plethysmographic waveform were evaluated after removal and after reinfusion of 10% estimated blood volume. The plethysmographic waveform variation (SPVplet) was measured as the difference between maximal and minimal peaks of waveform during the ventilatory cycle, and expressed as a percentage of the signal amplitude during apnoea. dUp(plet) and dDown(plet) were measured as the distance between the apnoeic plateau and the maximal or minimal plethysmographic systolic waveform, respectively. Intravascular volume was changed by removal of 10% of estimated blood volume and followed by equal volume replacement with Haemaccel. A 10% decrease in blood volume increased SPVplet from mean 17.0 (SD 11.8)% to 31.6 (28.0)% (P = 0.005) and dDown(plet) from 8.7 (5.1)% to 20.5 (12.9)% (P = 0.0005) compared with baseline. Changes in plethysmographic waveform correlated with changes in arterial SPV and dDown (r = 0.85; P = 0.0009). In the absence of invasive arterial pressure monitoring, ventilation-induced waveform variability of the plethysmographic signal measured from pulse oximetry is a useful tool in the detection of mild hypovolaemia.

Spontaneous intracerebral hemorrhage in critically ill patients: incidence over six years and associated factors

OBJECTIVE

Intracerebral hemorrhage (ICH) is associated with a high mortality. The present study sought to determine the incidence of spontaneous ICH in an intensive care unit (ICU) and associated factors.

DESIGN

A 6 year retrospective study.

SETTING

A general ICU in a university hospital.

PATIENTS

All ICU patients developing ICH were included in the study. All trauma and neurosurgical patients were excluded, as well as patients who were admitted to the ICU because of ICH.

MEASUREMENTS AND RESULTS

During the study period 3032 patients were hospitalized in the ICU, and 834 were excluded. The remaining 2198 patients comprised the study population. Computed tomography of the head was performed in a total of 227 patients, and the 9 patients found to have new onset ICH comprise the group of interest. None of these patients were hypertensive. Seven of the patients had either a primary hematologic malignancy or bone marrow transplantation. Eight had thrombocytopenia of <100x10(9)/l (median 10x10(9)/l, range 3-150x10(9)/l), and in 6 it preceded ICH by 5 days or more. Only in one patient were both PTT and PT prolonged. All were mechanically ventilated with high peak inspiratory pressure (PIP) (median 37 cm H2O, range 20-43 cm H2O). Arterial carbon dioxide tension (PaCO2) was considerably elevated (median 65 mm Hg, range 41-87 mm Hg). All of the patients had impaired renal and hepatic function (urea: median 14 mmol/l, range 9.9-52 mmol/l; bilirubin: median 94 micromol/l, range 20-360 micromol/l), and five had septicemia. Eight of the patients bled to other sites before they developed ICH. All patients died shortly after the diagnosis of ICH.

CONCLUSIONS

Spontaneous nonhypertensive ICH is a rare, fatal event in the ICU. Associated factors include thrombocytopenia, the need for mechanical ventilation, elevated PIP and PaCO2, sepsis, and impaired hepatic and renal function.

Effect of haemofiltration on pathological fibrinolysis due to severe sepsis: a case report

Bleeding due to coagulopathy is a frequent complication of severe sepsis, especially in burn patients. The primary treatment is aimed at the underlying cause but additional supportive measures, consisting mainly of coagulation factor replacement, are frequently necessary. We describe the salutary effect of continuous veno-venous haemofiltration (CVVH) with predilution on diffuse haemorrhage in a patient with severe septic shock and renal failure. The diffuse haemorrhage was initially treated with replacement of coagulation factors. Prothrombin time and partial thromboplastin time became normal while diffuse bleeding continued and the thrombelastogram showed evidence of fibrinolysis. A short period of CVVH lead to the cessation of bleeding which was reflected by a normal thrombelastogram.

Blast lung injury from an explosion on a civilian bus

OBJECTIVE

To assess clinical signs and management of primary blast lung injury (BLI) from explosions in an enclosed space and to propose a BLI severity scoring system.

DESIGN

Retrospective analysis.

PATIENTS

Fifteen patients with primary BLI resulting from explosions on two civilian buses in 1996.

RESULTS

Ten patients were extremely hypoxemic on admission (PaO2 < 65 mm Hg with oxygen supplementation). Four patients remained severely hypoxemic (PaO2/fraction of inspired oxygen (FIO2) ratio of < 60 mm Hg) after mechanical ventilation was established and pneumothoraces were drained. Initial chest radiographs revealed bilateral lung opacities of various sizes in 12 patients (80%). Seven patients (47%) had bilateral pneumothoraces and two patients had a unilateral pneumothorax. Five (33%) had clinically significant bronchopleural fistulae. After clinical and laboratory data were collected, a BLI severity score was defined based on hypoxemia (PaO2/FIO2 ratio), chest radiographic abnormalities, and barotrauma. Severe BLI was defined as a PaO2/FIO2 ratio of < 60 mm Hg, bilateral lung infiltrates, and bronchopleural fistula; moderate BLI as a PaO2/FIO2 ratio of 60 to 200 mm Hg and diffuse (bilateral/unilateral) lung infiltrates with or without pneumothorax; and mild BLI as a PaO2/FIO2 ratio of > 200, localized lung infiltrates, and no pneumothorax. Five patients developed ARDS with Murray scores > 2.5. Respiratory management included positive pressure ventilation in the majority of the patients and unconventional methods (ie, high-frequency jet ventilation, independent lung ventilation, nitric oxide, and extracorporeal membrane oxygenation) in patients with severe BLI. Of the four patients who had severe BLI, three died. All six patients with moderate BLI survived, and four of five with mild BLI survived (one with head injury died).

CONCLUSIONS

BLI can cause severe hypoxemia, which can be improved significantly with aggressive treatment. The lung damage may be accurately estimated in the early hours after injury. The BLI severity score may be helpful in determining patient management and prediction of final outcome.

Systolic pressure variation predicts the response to acute blood loss

STUDY OBJECTIVE

To evaluate systolic pressure variation (SPV), defined as the difference between the maximum and minimum systolic blood pressure measured during a controlled mechanical respiratory cycle, as a predictor of the cardiac output (CO) response to an acute decrease in ventricular preload.

DESIGN

Prospective study with each subject serving as his or her own control.

SETTING

Cardiac surgery operating rooms of a university medical center.

PATIENTS

15 adults with good ventricular function undergoing coronary artery bypass grafting.

INTERVENTION

During stable anesthetic conditions and before surgical stimulation, 500 ml of blood was removed from each patient over 10 minutes.

MEASUREMENTS AND MAIN RESULTS

CO, central venous pressure (CVP), pulmonary artery diastolic pressure, and pulmonary artery occlusion pressure (PAOP), and SPV before and after phlebotomy were recorded. Phlebotomy was associated with significant decreases in CVP, PAOP, and CO, and an increase in SPV. Of these variables, SPV was the best predictor of the percent decrease in CO resulting from blood loss.

CONCLUSION

SPV is a dynamic measurement, which, by revealing the response to small cyclical changes in left ventricular preload that occur during the controlled mechanical respiratory cycle, is a better predictor than central filling pressures of the response of CO to acute decreases in preload that occur as a result of acute blood loss.

Helium versus oxygen for tracheal gas insufflation during mechanical ventilation

OBJECTIVE

To evaluate and compare the effect of tracheal gas insufflation using two gases with different physical properties, helium and oxygen, as an adjunct to conventional mechanical ventilation in patients with respiratory failure.

DESIGN

Prospective, intervention study.

SETTING

General intensive care unit in a tertiary university medical center.

PATIENTS

Seven sedated and paralyzed patients with respiratory failure of various etiologies. All patients were ventilated in the volume-control mode (tidal volume 5 to 7 mL/kg). Inclusion criteria were PaCO2 of > or =50 torr (> or =6.7 kPa), together with peak inspiratory pressure of > or =35 cm H2O and respiratory rate of > or =14 breaths/min.

INTERVENTIONS

All patients were intubated with an endotracheal tube that had an additional lumen opening at its distal end, through which tracheal gas insufflation was administered. The tracheal gas insufflation was applied continuously throughout the respiratory cycle at three flow rates (2, 4, and 6 L/min) with two gases, oxygen and helium, while the ventilatory settings were maintained constant.

MEASUREMENTS AND MAIN RESULTS

In addition to airway pressures and arterial blood gases, the relative efficacy of tracheal gas insufflation with each gas was estimated using a "coefficient of efficiency" (which we defined as the change in PaCO2/peak inspiratory pressure) compared with baseline measurements. Tracheal gas insufflation with both gases decreased PaCO2 significantly (p < .05) at all flow rates. This effect was accompanied by an increase in airway pressure with both gases (oxygen and helium). However, at flow rates of 6 L/min, tracheal gas insufflation with helium resulted in lower peak inspiratory pressure than with oxygen. Tracheal gas insufflation with helium was more effective (as estimated by the coefficient of efficiency) than with oxygen at all flow rates (p < .05).

CONCLUSION

In volume-controlled, mechanically ventilated patients with respiratory failure, tracheal gas insufflation with helium might be suggested as an alternative to oxygen.

Foregoing life-sustaining treatment in an Israeli ICU

OBJECTIVE

To determine whether physicians in Israel withhold and/or withdraw life-sustaining treatments.

DESIGN

A prospective, descriptive study of consecutively admitted patients. Patients were prospectively evaluated for diagnoses, types and reasons for foregoing life-sustaining treatment, mortality and times from foregoing therapy until mortality.

SETTING

A general intensive care unit of a university hospital in Israel.

RESULTS

Foregoing life-sustaining treatment occurred in 52 (13.5%) of 385 patients admitted and 5 (1%) had cardiopulmonary resuscitation. Withholding therapy occurred in 48 patients. Four patients with brain death had all treatments withdrawn. No patient had antibiotics, nutrition or fluids withheld or withdrawn. Time from foregoing therapy until death was 2.9 +/- 0.6 days. Thirty-one of 48 (65%) patients who had therapy withheld died within 48 h.

CONCLUSIONS

Withholding life-prolonging treatments is common in an Israeli intensive care unit whereas withdrawing therapy is limited to brain dead patients. Terminal patients die soon after withholding, even if the therapy is not withdrawn. Withholding treatments should be an option for patients and professionals who object to withdrawing therapies.

Perioperative ischemia and cardiac complications in major vascular surgery: importance of the preoperative twelve-lead electrocardiogram

PURPOSE

To investigate the associations between specific preoperative 12-lead electrocardiogram (ECG) abnormalities, perioperative ischemia, and postoperative myocardial infarction or cardiac death in major vascular surgery.

METHODS

Two prospective studies on perioperative myocardial ischemia performed in two tertiary university hospitals were combined to include 405 patients. All preoperative ECGs were analyzed according to the Sokolow-Lyon criteria for left ventricular hypertrophy by investigators who were blinded to the patients' perioperative clinical course. Perioperative myocardial ischemia was detected by continuous ECG recording, and postoperative cardiac complications included myocardial infarction and cardiac death.

RESULTS

A total of 19 postoperative cardiac complications occurred (two cardiac deaths and 17 myocardial infarctions). Voltage criteria for left ventricular hypertrophy (78 patients, 19%) and ST segment depression greater than 0.5 mm (98 patients, 24.2%) on preoperative ECGs were both significantly associated with postoperative myocardial infarction or cardiac death (odds ratio, 4.2 and 4.7; p = 0.001 and 0.0005, respectively) and with longer intraoperative and postoperative myocardial ischemia. In each of the two study groups, a preoperative ECG abnormality that involved voltage criteria, ST segment depression, or both (134 patients, 33.1%) was more predictive of postoperative cardiac complications than any other preoperative clinical variable, including a history of myocardial infarction or angina pectoris, diabetes mellitus, pathologic Q-wave by ECG, or preoperative myocardial ischemia. The combined duration of intraoperative and postoperative ischemia and the preoperative ECG with either voltage criteria or ST segment depression were the only independent factors associated with adverse cardiac events by multivariate analysis (p < or = 0.0001 and p = 0.02, respectively).

CONCLUSION

Left ventricular hypertrophy and ST segment depression on preoperative 12-lead ECGs are important markers of increased risk for myocardial infarction or cardiac death after major vascular surgery.

Continuous spinal anaesthesia using a standard epidural set for extracorporeal shockwave lithotripsy

PURPOSE

Continuous spinal anaesthesia (CSA) offers considerable advantages over "single shot" spinal or epidural anaesthesia since it allows titration of anaesthesia using small doses of local anaesthetics (LA). We evaluated the feasibility of CSA using a standard epidural set for extracorporeal shockwave lithotripsy (ESWL).

METHODS

Charts of 100 consecutive CSAs for ESWL were retrospectively reviewed. Lumbar CSA was performed using a 20G epidural catheter through an 18G Tuohy needle. The CSA was preplanned, or followed inadvertent dural puncture. Small LA boluses were injected to achieve the desired sensory level of anaesthesia. Demographic data, anaesthetic duration, LA doses, the most cephalad sensory level to pinprick, arterial blood pressure, heart rate, use of systemic sympathomimetics and complications were recorded.

RESULTS

Mean age was 66.2 +/- 9.9 (SD). The ASA status was III-IV in 54.1% and 5.5% of the preplanned and inadvertent patients, respectively. In 85 anaesthetics, hyperbaric bupivacaine 0.1% (9.7 +/- 7.5 mg) was used as the sole anaesthetic. Sensory level was T4-T8. Maximal decrease in systolic and diastolic blood pressures and heart rate was 19.0 +/- 9.8%, 13.4 +/- 13.3%, and 7.2 +/- 11.7 respectively. Intravenous sympathomimetics were used in nine of 82 (11.0%) preplanned, and in six of 18 (33.3%) inadvertent anaesthetics. Post dural puncture headache appeared following two of 82 (2.5%) preplanned, and four of 18 (22.2%) inadvertent anaesthetics. No postanaesthetic neurological deficit was detected.

CONCLUSION

Continuous spinal anaesthesia, using a standard epidural set and hyperbaric bupivacaine is feasible for ESWL in high risk patients. Inadvertent dural puncture does not preclude CSA under these circumstances.

Ethical issues of clinical trials for the pulmonary artery catheter

OBJECTIVE

To review the literature addressing ethical issues related to clinical research and the pulmonary artery catheter (PAC).

DATA SOURCE

All pertinent English language articles dealing with ethical issues related to clinical research and the PAC were retrieved from 1970 through 1996.

STUDY SELECTION

Articles were chosen for review if ethical issues related to clinical research and the PAC were studied or reviewed.

DATA EXTRACTION

From the articles selected, information was obtained about the ethics of clinical research related to the PAC.

DATA SYNTHESIS

Many current procedures and treatments used on a daily basis have not been proven effective by clinical trials. Studies showing increased mortality with the use of PACs are worrisome. Many clinicians have strong preferences about the use of PACs for various indications and there have been difficulties performing clinical trials. Clinical equipoise occurs when competent physicians are content to have their patients receive any of the various treatments in a randomized trial because, based on available data, none has proven preferable. Clinical equipoise for pulmonary artery catheterization for various indications is unknown. If >70% of experts determine that pulmonary artery catheterization is indicated or contraindicated for specific indications, clinical equipoise does not exist and a trial could not ethically be performed for these indications. Indications and contraindications for pulmonary artery catheterization for these indications, however, should be determined. Clinical equipoise would be present if <70% of experts favor pulmonary artery catheterization for a specific indication and trials could be performed in patients with these disorders.

CONCLUSION

Randomized clinical trails of pulmonary artery catheterization can ethically be conducted.

The issue of a U.S. Food and Drug Administration moratorium on the use of the pulmonary artery catheter

OBJECTIVE

To review the literature addressing the issue of a U.S. Food and Drug Administration (FDA) moratorium on use of the pulmonary artery catheter (PAC).

DATA SOURCE

Pertinent English language articles dealing with medical devices including the PAC were retrieved from 1976 through 1996.

STUDY SELECTION

Articles were chosen if issues related to medical devices were studied or reviewed.

DATA EXTRACTION

From the articles selected, information about the 1976 Medical Device Amendment and the PAC was obtained.

DATA SYNTHESIS

In 1976, the Medical Device Amendment gave the FDA power over medical devices. The pulmonary artery catheter is considered a class II device and was on the market before passage of the 1976 Act. Class II devices require general and specific controls to reasonably assure safety and effectiveness. A reasonable assurance of safety occurs when the probable benefits to health from the use of the device outweigh any probable risks. If a monitor measures an established and well-understood variable and the intended use claim is limited to the measurement of that variable, then the effectiveness consists of determining device safety and performance defined as the measurement of agreement with a recognized reference method. Deaths and serious injuries secondary to pulmonary artery catheterization are extremely rare despite more than 25 years of use. Pulmonary artery catheter manufacturer's indications for use are measurements such as hemodynamic pressures, thermodilution cardiac output, continuous cardiac output, mixed venous oxygen saturation, and blood sampling; intended uses have not included claims of clinical benefit. Evidence exists that pulmonary artery catheterization provides agreement with established measurements including pressure and cardiac output. Evidence also exists that pulmonary artery catheter derived data are unobtainable clinically, that the derived data helps in therapy changes and may lead to more appropriate therapy. The evidence demonstrates an absence of unreasonable risk of injury from pulmonary artery catheterization and provision of important clinical results. Therefore, pulmonary artery catheterization meets FDA requirements for safety and effectiveness.

CONCLUSION

An FDA moratorium on the use of the PAC is not indicated.

Legionnaire's disease during pregnancy: a case presentation and review of the literature

Acute pneumonia complicating pregnancy can have serious consequences for both the mother and the fetus. Streptococcus pneumoniae remains the most common bacterial pathogen, but Legionella pneumophila must be considered as well, especially in severe multisystem disease. With severe disease, premature delivery may occur as has been described in the only previous report of Legionnaire's disease during pregnancy. We present here the first report of Legionnaire's disease in pregnancy, resulting in the term delivery of a healthy infant. Also presented is an extensive review of the literature.

Influence of alterations in foregoing life-sustaining treatment practices on a clinical sepsis trial. The HA-1A Sepsis Study Group

OBJECTIVES

To evaluate the timing of foregoing life-sustaining treatments in patients enrolled in a sepsis trial and to determine their influence on patient outcome and trial results.

DESIGN

Subset of patients in a prospective, randomized, double-blind, placebo-controlled study.

SETTING

Twenty-three academic medical centers.

PATIENTS

Enrolled patients who had life-sustaining therapies withheld or withdrawn.

MEASUREMENTS AND MAIN RESULTS

The number of patients, types of disorders and interventions, reasons, and timing of withholding and withdrawing life-sustaining treatments and their effect on mortality and trial results were assessed. Foregoing of life-sustaining therapies took place in 117 (22%) of 543 patients and occurred within 72 hrs of study drug administration in 38 (32%) patients. Withholding treatment (60%) was more common than withdrawing treatment (40%), but withdrawing treatment was more frequent (51%) than withholding treatment (20%) in the first 72 hrs of the trial (p < .01). Sixty-one (52%) patients had severe underlying disorders with a poor prognosis. The hospital mortality rate was 94% (of the 117 patients). The mean time (SEM) from withholding or withdrawing of treatment until death was 2.83 +/- 0.57 and 0.32 +/- 0.13 days, respectively (p < .001). Patients who had therapies foregone in the first 24, 48, and 72 hrs after receiving the study drug had higher mortality rates in the first 72 hrs (p < .01).

CONCLUSIONS

A substantial number of patients enrolled in a sepsis trial had severe underlying diseases and had foregoing of therapies early in the course of the trial, which led to a higher early mortality rate. Enrollment of patients in clinical trials with severe underlying disorders with a high likelihood of having therapies foregone may bias the potential for showing the efficacy of new therapeutic modalities.

Is the patient's right to die evolving into a duty to die?: Medical decision making and ethical evaluations in health care

When patient or family requests for continued life-sustaining treatments conflict with doctor recommendations, different conclusions as to what is beneficial for the patient may arise. Past practices usually accepted patient or family requests based on the principle of autonomy or that the doctor's primary responsibility is to the individual patient. Many patients die in intensive care units after doctors forego life-prolonging interventions. Health care changes and cost containment have led to a change in the classical ethical model of the patient-doctor relationship such that concerns for societal requirements increasingly overrule those for individual patient needs. The ability to keep patients alive with little likelihood of recovery and the recognition of escalating health costs have led to calls for the needs of society and distributive justice to be taken into account. A tendency to justify a duty to die for these patients has arisen. Recent legal decisions in cases with conflicts between families and health care providers and institutions over foregoing life-sustaining therapies have decided for the families against doctors and hospitals, compelling institutions and their staff to act contrary to their ethical views. Value judgments of doctors are sometimes confused with medical indications for therapy. Doctors have defined therapies as futile or non-beneficial based on their own values and even withdrawn life-sustaining treatments without patient or family input. In some cases, the right to die is leading to the duty to die even against patient or surrogate wishes. Such observations indicate the need for rigorous analyses of medical decision making in this context and for ethical evaluations in health care in general.

[Treatment of concomitant coronary and carotid disease]

The optimal surgical treatment for concomitant carotid and coronary artery disease is controversial. Between 1991 and 1995 we performed 34 procedures for combined disease of the carotid and coronary arteries. The first 8 operations were carotid endarterectomies followed by coronary artery bypass grafting (staged procedure). The next 26 operations were performed during a single anesthesia (combined procedure). The patients were 28 men and 6 women, aged 58-81 years (mean 68). 80% were in functional class III or IV. In 40% ventricular function was moderately or severely reduced. There was an average of 3.6 grafts per patient, and in all except 3 patients the left internal thoracic artery was used as a conduit for coronary artery bypass grafting. 30% had symptomatic carotid stenosis; there was no perioperative mortality. In the staged procedure group, 2 patients had postoperative cardiac complications: in 1 acute coronary insufficiency and acute myocardial infarction in the other. 1 had postoperative, transient, amaurosis fugax. In the combined procedure group, 1 had a myocardial infarction and 1 a minor occipital stroke. During follow-up, 1 patient died 4 months after operation of myocardial infarction, and 1 had a minor stroke. The results suggest that the combined procedure is safe and carries low risk of both mortality and morbidity. Whenever cardiac disease is stable and there is no main coronary artery disease, a staged procedure should be considered. In any other situation we continue to perform the combined procedure.

The spectrum of septic encephalopathy. Definitions, etiologies, and mortalities

OBJECTIVE

To determine whether the severity of septic encephalopathy is correlated with gram-negative bacteremia and mortality and whether there exists a single or combination of metabolic derangements(s) that cause septic encephalopathy.

DESIGN AND SETTING

Prospective case series in an academic medical center.

PATIENTS

Fifty patients selected according to clinical and laboratory criteria for severe sepsis. The criteria included temperature, heart rate, respiratory rate, and hypotension and/or signs of systemic hypoperfusion.

MAIN OUTCOME MEASURES

A single or combination of metabolic and laboratory derangements and organ failures, three different methods to grade the severity of septic encephalopathy, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, gram-negative bacteremia and infection, and mortality.

RESULTS

Encephalopathy was associated with an increase in mortality when graded by the Glasgow Coma Score; a score of 15 had 16% mortality, 13 to 14 had 20%, 9 to 12 had 50%, and 3 to 8 had 63% mortality (P < .05). Bacteremia was associated with encephalopathy; 13% of septic patients without encephalopathy vs 59% of patients with encephalopathy had bacteremia (P < .001) when graded by altered mental status. Septic encephalopathic patients had elevated serum urea nitrogen and bilirubin levels, increased APACHE II scores, and a higher incidence of renal failure.

CONCLUSIONS

The severity of septic encephalopathy correlated with mortality, bacteremia, and renal and hepatic dysfunction. The Glasgow Coma Score is a useful tool for characterizing septic encephalopathy. Considerable variations can be found according to different criteria used to classify septic encephalopathy.

Euthanasia

This article provides a brief review of the history of euthanasia. The problems involved in withholding or withdrawing treatment, physician-assisted suicide, and arguments for or against euthanasia are discussed. Changes in both societal and physician attitudes and practices are presented.

An evaluation of the hemodynamic effects of HA-1A human monoclonal antibody

OBJECTIVES

We sought to determine whether there might be acute changes in hemodynamics attributable to HA-1A, a monoclonal antibody to endotoxin, in patients with presumed Gram-negative sepsis.

DESIGN

Post hoc analysis of a multicenter, randomized, double-blind, placebo-controlled study.

PATIENTS

A total of 543 patients with severe sepsis presumed to be caused by Gram-negative bacteria who were enrolled in a clinical trial to evaluate the efficacy and safety of HA-1A human monoclonal antibody.

INTERVENTIONS

Patients were randomly assigned to receive either 100 mg of HA-1A or placebo.

MEASUREMENT AND MAIN RESULTS

Patients were grouped by the study drug, HA-1A, or placebo, and the presence or absence of Gram-negative bacteremia. Hemodynamic variables were monitored from before, until 72 hrs after infusion of the study drug. For the entire study population (n = 543), no changes over time attributable to study drug were noted in the mean arterial pressure (p > .19), heart rate (p > .53) or the need for vasopressor administration (p > .62). One hundred ninety-seven patients underwent pulmonary artery catheterization and had hemodynamic data available from before the infusion of HA-1A or placebo until at least 12 hrs after infusion. Evaluating all 197 patients on an intent to treat basis demonstrated no significant differences over time in cardiac index (p > .15), oxygen delivery index (p > .43), or left ventricular stroke work index (p > .48) between patients who received HA-1A and those patients receiving placebo. Grouping patients by the presence of Gram-negative bacteremia and study drug received also failed to demonstrate any significant difference attributable to HA-1A in mean arterial pressure (p > .54), heart rate (p > .84), cardiac index (p > .13), oxygen delivery index (p > .05), or left ventricular stroke work index (p > .48) between populations.

CONCLUSION

There is no apparent relationship between the administration of HA-1A, the presence of Gram-negative bacteremia, and hemodynamic profiles over the 72-hr study period.

Prolonged postoperative myocardial ischaemia and infarction in vascular surgery performed under regional anaesthesia

The importance of prolonged postoperative myocardial ischaemia in cardiac outcome has recently been emphasised. The present study examines the correlation between perioperative ischaemia and myocardial infarction (MI) in patients undergoing peripheral vascular surgery (PVS) under regional anaesthesia. One-hundred-and-forty consecutive peripheral vascular operations under regional anaesthesia were prospectively analysed, using Holter monitoring for perioperative myocardial ischaemia (defined as down sloping or horizontal ST-segment depression of > or = 1 mm) and postoperative cardiac outcome. The study was approved after informed consent. There were 82 carotid endarterectomies under cervical block and 58 infrainguinal bypass procedures under continuous spinal or epidural anaesthesia. IHD was present in 53.6% cases: previous MI-38%; angina pectoris-33%; previous CABG/PTCA-24%. Holter monitoring started about 20 hours before surgery and continued for 45 hours. After surgery patients were followed for signs of cardiac complications; daily 12 lead ECG; 6 hourly CK-MB isoenzymes during the first 24 postoperative hours and later whenever indicated. MI diagnosis was based on chest pain, permanent new ECG changes and CK-MB elevation. There was no 30-day mortality. Postoperative MI occurred in seven patients (5%). Five of the postoperative MI were non-Q-wave infarctions. The majority (71%) of the adverse cardiac events started within 24 hours of surgery, and the latest occurred 52 and 72 hours post surgery. In 65 cases (46.4%) there were 259 episodes of significant ST-depression. In 75 (53.6%) cases ischaemic episodes were not detected. Patients with postoperative cardiac events had significantly more and longer ischaemic episodes in all three perioperative periods than those without such events.(ABSTRACT TRUNCATED AT 250 WORDS)

Perioperative myocardial ischemia in carotid endarterectomy under cervical plexus block and prophylactic nitroglycerin infusion

Perioperative myocardial ischemia was evaluated in 36 consecutive carotid endarterectomy procedures carried out on patients with a high (72.2%) prevalence of ischemic heart disease. The procedures were performed under cervical plexus block plus a prophylactic intravenous nitroglycerin infusion. Findings of myocardial ischemia on perioperative (48 hours) continuous electrocardiogram recordings were correlated with preoperative cardiac status, perioperative continuous intra-arterial blood pressure measurements, and postoperative cardiac outcome. In two patients, ST segment analysis was un-interpretable because of bundle-branch blocks. Altogether, 64 episodes of significant ST segment depression were detected in 18 (52.9%) of the remaining procedures. In 8 (23.5%) procedures, ST segment depressions occurred either during carotid artery clamping at the time of the largest rise in blood pressure or within 2 hours of declamping, when blood pressure tended to decline. There were four (11.7%) postoperative cardiac events: three myocardial infarctions (one Q wave and two non-Q wave) and one episode of unstable angina pectoris. All four patients with cardiac events had early signs of myocardial ischemia either at the time of cross-clamping, or soon after declamping of the carotid artery. All myocardial infarctions developed following prolonged (> 10 hours) myocardial ischemia, starting with the first 20 hours after surgery. Thus, ST segment depression occurring during clamping or soon after carotid declamping was associated with cardiac complications (sensitivity 100% and specificity 86.6%) and suggests the possible usefulness of on-line ST segment trend monitoring.

Importance of long-duration postoperative ST-segment depression in cardiac morbidity after vascular surgery

Major vascular surgery is associated with a high incidence of cardiac ischaemic complications. By means of continuous perioperative electrocardiographic recording, we studied 151 consecutive patients undergoing major vascular surgery to find out the characteristics of any myocardial ischaemia and the relation to outcome. 13 (8.6%) patients had postoperative cardiac events (6 myocardial infarctions, 2 unstable angina, and 5 congestive heart failure). There were 342 perioperative ischaemic episodes shown by ST-segment depression; 164 (48%) occurred postoperatively. Postoperative ischaemic episodes were significantly longer than episodes before or during operations (3.2 vs 1.7 and 1.5 min per h monitored, respectively, p < 0.001). Both Detsky's cardiac risk index and long-duration (> 2 h) preoperative ischaemia were predictive of postoperative cardiac complications (odds ratios in univariate analysis 3.3, p = 0.03, and 7.2, p = 0.009, respectively). However, long-duration (> 2 h) postoperative ischaemia was the only factor significantly associated with cardiac morbidity in multivariate logistic regression analysis (odds ratio 21.7, p = 0.001). Long-duration ST-segment depression preceded most (84.6%) postoperative cardiac events, including myocardial infarctions, and no cardiac event was preceded by ST-segment elevation. 5 of the 6 postoperative myocardial infarctions were non-Q-wave infarctions. We conclude that long-duration subendocardial ischaemia, rather than acute coronary artery occlusion, may bring about postoperative myocardial injury and complications.