H. A. Tillmann Hein

Hemodynamic changes during laparoscopic cholecystectomy in patients with severe cardiac disease

STUDY OBJECTIVE To evaluate the hemodynamic changes and need for pharmacologic interventions during laparoscopic cholecystectomy in patients with severe cardiac dysfunction. DESIGN Prospective open study. SETTING University hospital. PATIENTS 17 ASA physical status III and IV patients with severe cardiac dysfunction undergoing elective laparoscopic cholecystectomy. INTERVENTIONS A standardized general anesthetic and surgical technique was used for all patients. In addition to routine monitoring, invasive hemodynamic monitoring included radial and pulmonary artery (PA) cannulation. MEASUREMENTS AND MAIN RESULTS Hemodynamic parameters were recorded prior to induction of anesthesia, 5 minutes after induction of anesthesia but prior to incision, 5 minutes after carbon dioxide (CO2) insufflation and head-up tilt, every 10 minutes after change of position, after deflation of the abdomen and return to supine position, and 10 minutes after attaining supine position. Need for any pharmacologic interventions [to maintain mean arterial pressure (MAP) < 100 mmHg and/or systemic vascular resistance (SVR) < 2,000 dynes sec/cm-5, and/or cardiac index (CI) > 1.5 L/min/m2] and the incidence of any myocardial morbidity and mortality was noted. CI decreased significantly (p < 0.05) following insufflation and remained low until exsufflation. MAP, SVR, and PA occlusion pressure increased significantly (p < 0.05) after CO2 insufflation. Three of the 17 patients required administration of nitroglycerin to maintain the MAP and SVR within the accepted limits, one of whom also required administration of dobutamine to maintain CI. There was no myocardial morbidity or mortality in the perioperative period. CONCLUSION Laparoscopic cholecystectomy in patients with severe cardiac dysfunction results in significant hemodynamic changes.

Readmission to the intensive care unit after liver transplantation

ObjectiveWe undertook this study to understand the factors at our transplant center that contribute to patients’ return to the ICU after their liver transplant and their initial discharge from that unit. Patients who, after liver transplantation, fail discharge from the Intensive Care Unit (ICU) and must be readmitted to that unit may well utilize many more resources than those patients who are well enough to stay out of the ICU. DesignA retrospective review of a prospectively maintained liver transplant research database followed by a retrospective review of (a subgroup) patient charts and contemporaneous controls. SettingA large metropolitan tertiary care center and adult liver transplant center. PatientsA total of 1,197 consecutive adult patients who underwent their initial liver transplantation from 1984 to 1996. InterventionReadmission to the intensive care unit after adult liver transplantation and discharge from that unit. Main ResultsOnly recipient age, pretransplant synthetic function labs (protime and albumin), bilirubin levels, and intraoperative blood product requirements could be statistically linked to the group requiring ICU readmission. The primary etiology for ICU readmission was cardiopulmonary deterioration. Readmission was associated with significantly lower patient and graft survivals. A detailed review of 23 patients transplanted from October 1994 to June 1996 was made, with special emphasis on cardiopulmonary status (hemodynamics, respiratory variables, and chest radiograph findings). This subgroup was compared with 30 temporally matched controls who were not readmitted to the ICU. Intravascular fluid overload and lower inspiratory capacity were significant factors related to ICU readmission. Readmitted patients had a longer hospitalization with higher hospital charges than the control group. ConclusionsWe conclude that the most important means of preventing ICU readmission in liver transplantation patients is to optimize cardiopulmonary function and status. Close monitoring of fluid balance to avoid hypervolemia is essential. Readmitted patients have a greater resource utilization and have lower survival rates.

Delayed neurological deficit after total hip arthroplasty.

P atients undergoing total hip arthroplasty (THAI may rarely develop neurological complications that may present as transient confusion or, if severe, as coma or death (1). Suggested etiologies for these impairments include hypoxia caused by pulmonary embolism or from paradoxical cerebral emboli passing through a patent foramen ovale or other intracardiac shunt (2,3). The pathogenesis of neurological problems surrounding arthroplastic surgery is thought to be fat emboli from the bone marrow being released by an increase in intramedullary pressure (2,4). We report two cases in which patients underwent successful and uncomplicated THA but developed critical neurologic impairment hours later, leading to the death of one patient and the prolonged recovery of the other. The symptoms of this neurological complication were atypical in that they did not present until 2-3 h after what seemed to be a normal recovery from anesthesia and surgery. Neither patient, on close examination, had demonstrable intracardiac shunts.

Duration of Vecuronium-Induced Neuromuscular Block as a Predictor of Liver Allograft Dysfunction

The major causes of liver graft failure are acute rejection, technical failure, and primary nonfunction (PNF).This study was undertaken to determine whether delayed return of neuromuscular function correlates with allograft primary dysfunction in humans given vecuronium. Twenty-two adult patients undergoing orthotopic liver transplantation were given an initial dose of vecuronium, 0.1 mg/kg intravenously (IV). All patients recovered from vecuronium-induced neuromuscular block prior to explantation. No additional neuromuscular blocker was given until the liver graft was implanted and reperfused. Fifteen minutes after reperfusion another 0.1 mg/kg vecuronium was given IV and recovery time from attaining complete neuromuscular block to return of the fourth twitch of a train-of-four was recorded. Patients were divided into three groups according to postoperative liver function. Group I consisted of 17 patients with immediate normal liver graft function. Group II consisted of four patients with primary dysfunction (PDF) [peak aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≫2000 U/L, prothrombin time ≫16 s, and poor quality and quantity of bile within 3 days postoperatively] which eventually recovered normal function. Group III consisted of one patient with PNF (uncorrectable coagulopathy, severe metabolic acidosis, rising AST and ALT, and minimal or no bile output), whose graft never recovered. Recovery time in Groups II and III was prolonged compared to Group I (P < 0.05). Recovery time in Group III was prolonged compared to Group II (P < 0.05). A test based on these results using a recovery time of ≫135 min as a predictor of PDF has a sensitivity and specificity of 80% and 76%, respectively. The positive and negative predictive values are 50% and 93%. Duration of neuromuscular block after vecuronium administration appears to be an early predictor of liver allograft function. (Anesth Analg 1995;80:526-33)

Sedation levels during propofol administration for outpatient colonoscopies.

The levels of sedation required for patients to comfortably undergo colonoscopy with propofol were examined. One hundred patients undergoing colonoscopy with propofol were enrolled. In addition to standard-of-care monitoring, sedation level was monitored with the Patient State Index (PSI) obtained from a brain function monitor, transcutaneous carbon dioxide (tcpCO2) was monitored with the TCM TOSCA monitor, and end-tidal carbon dioxide was monitored via nasal cannula. The Ramsay Sedation Score (RSS) was also assessed and recorded. After baseline data were obtained from the first 40 consecutive patients enrolled in the study, the remaining 60 patients were randomized into two groups. In one group the PSI value was blinded from the anesthesiologist and in the second group the PSI was visible and the impact of this information on the management of the sedation was analyzed. Overall 96% of patients reached levels of deep sedation and 89% reached levels of general anesthesia. When comparing the blinded to PSI versus unblinded groups, the blinded group had a significantly lower PSI and higher RSS and tcpCO2, indicating the blinded group was maintained at a deeper sedation level with more respiratory compromise than the unblinded group. Patients undergoing colonoscopy under propofol sedation delivered by a bolus technique are frequently taken to levels of general anesthesia and are at risk for respiratory depression, airway obstruction, and hemodynamic compromise.

Dexmedetomidine infusion for analgesia up to 48 hours after lung surgery performed by lateral thoracotomy.

Patients undergoing a lateral thoracotomy for pulmonary resection have moderate to severe pain postoperatively that is often treated with opioids. Opioid side effects such as respiratory depression can be devastating in patients with already compromised respiratory function. This prospective double-blinded clinical trial examined the analgesic effects and safety of a dexmedetomidine infusion for postthoracotomy patients when administered on a telemetry nursing floor, 24 to 48 hours after surgery, to determine if the drugs known early opioid-sparing properties were maintained. Thirty-eight thoracotomy patients were administered dexmedetomidine intraoperatively and overnight postoperatively and then randomized to receive placebo or dexmedetomidine titrated from 0.1 to 0.5 μg·kg·h−1 the day following surgery for up to 24 hours on a telemetry floor. Opioids via a patient-controlled analgesia pump were available for both groups, and vital signs including transcutaneous carbon dioxide, pulse oximetry, respiratory rate, and pain and sedation scores were monitored. The dexmedetomidine group used 41% less opioids but achieved pain scores equal to those of the placebo group. The mean heart rate and systolic blood pressure were lower in the dexmedetomidine group but sedation scores were better. The mean respiratory rate and oxygen saturation were similar in the two groups. Mild hypercarbia occurred in both groups, but periods of significant respiratory depression were noted only in the placebo group. Significant hypotension was noted in one patient in the dexmedetomidine group in conjunction with concomitant administration of a beta-blocker agent. The placebo group reported a higher number of opioid-related adverse events. In conclusion, the known opioid-sparing properties of dexmedetomidine in the immediate postoperative period are maintained over 48 hours.

Cardiorespiratory arrest with laryngeal oedema in pregnancy- induced hypertension

A 17-year-old black female with pregnancy-induced hypertension (PIH) suffered cardiorespiratory arrest on arrival in the recovery room after Caesarean section under general endotracheal anaesthesia. Successful resuscitation included orotracheal intubation, complicated by severe laryngeal oedema. Causative mechanisms are discussed.

Effect of intravenous sedation on the outcome of transvaginal oocyte retrieval: a comparative study of propofol- and methohexital-based techniques

Abstract This study retrospectively compares patients who underwent outpatient transvaginal follicle aspiration with either a propofol- or methohexital-based intravenous sedation technique. Data collected from patient charts (n = 212) over a 46-month period were analyzed to determine the effects of each sedation technique on procedure and recovery times, number of retrieved ova, as well as rates of nausea, fertilization, cleavage, pregnancy, and delivery. All patients were included in the study, regardless of age or diagnosis. procedure time was lower in the propofol group (51 t 18 min) than in the methohexital group (61 I 20 min) (p > 0.01). Patients in the methohexital group (139 2 51 min) spent more time in the recovery room than did those in the propofol group (71 ? 34 min) (p > 0.01). The nausea rates were significantly lower in the propofol group compared with the methohexital group (1.9% vs. 14.4%, respectively) (p > 0.02). Fertilization rate in the propofol group was 77.7% and was 62.9% in the methohexital group (p > 0.01). The numbers of retrieved ova and the cleavage rates were similar in both groups. The rate of pregnancy in patients sedated with propofol (46.1%) was higher than the methohexital group (26.9%) (p > 0.02). Delivery rate was 38.5% in the propofol group and 20.6% in the methohexital group (p > 0.02). In summary, propofol intravenous sedation for transvaginal follicle aspiration was associ- ated with an improved outcome. Pregnancy and delivery rates were higher while nausea, an unpleasant side effect, was sharply reduced.

Use of general anesthetic only vs general anesthetic combined with paravertebral block for perioperative pain management after first rib resection

Many patients with thoracic outlet syndrome develop a chronic pain syndrome (1). Some of these patients require surgical decompression of the thoracic outlet to alleviate their symptoms. Surgical decompression is accomplished by performing a first rib resection with cervical sympathectomy. There are 2 approaches to first rib resection, supraclavicular and transaxillary. The preferred surgical technique at Baylor University Medical Center is transaxillary (2–4). Postoperative pain management for patients with thoracic outlet syndrome is compounded by the fact that most of these patients are on long-term potent analgesics at home before the operation.