Postoperative Schmerztherapie auf Allgemeinen Krankenpflegestationen

Zusammenfassung.

Seit 1985 wurden 1947 Patienten durch einen Anästhesiologischen Schmerzdienst auf Allgemeinen Krankenpflegestationen an insgesamt 13 971 Tagen betreut. Bei den 1736 Patienten mit Epiduralanalgesie (EA) mit 0,175 – 0,25% Bupivacain betrug die mittlere Behandlungsdauer 7 (1 – 53) Tage, bei 50% der Patienten länger als eine, bei 11% mehr als 2 Wochen. 183 Patienten mit PCA (Tramadol, Piritramid) wurden im Mittel an 4 (1 – 23) Tagen, hiervon 21,4% länger als eine Woche behandelt. Seit Einführung des Schmerzdienstes sank die Häufigkeit therapiebedingter Komplikationen unter der EA von 10,4% signifikant auf 6% in den letzten beiden Jahren, z. B. traten gravierende Hypotensionen in den letzten Jahren nicht mehr auf. Obwohl nur in Ausnahmefällen eingesetzt, traten zwei Fälle einer schweren Atemdepression nach epiduralem Morphin auf. Unter der PCA wurden ebenfalls zwei Fälle (1% der Anwendungen) beobachtet. Außerdem wurden vier schwere Komplikationen mit einem Todesfall im Rahmen der nicht vom Schmerzdienst betreuten Standardschmerztherapie dokumentiert. Die Anbindung des Schmerzdienstes an den Aufwachraum hat sich bewährt, da hier die Wirksamkeit und Verträglichkeit der auf den Allgemeinstationen vorgesehenen Therapie geprüft werden kann. Auf den Stationen muß mittels täglicher Visiten anhand standardisierter Protokolle der weitere Verlauf systematisch überwacht werden. Unter diesen Rahmenbedingungen ist die Schmerztherapie auch mittels spezieller Verfahren (EA, PCA) auf Allgemeinen Pflegestationen praktikabel und vertretbar.

Abstract.

Despite major advances in knowledge and development of efficient techniques for pain control, many patients on surgical wards suffer from modest to severe pain following surgery or trauma. Therefore, in the University Hospital of Kiel, Germany, an anaesthesiology-based acute pain service (APS) was started in 1985 to improve this situation. Organization of an APS. The anaesthesiologist in training who manages the recovery unit serves as an APS for surgical wards and is supervised by a consultant. The anaesthesists on call are responsible after regular working hours. The activities of the APS are as follows: 1. Induction of sufficient postoperative analgesia in the recovery unit for all surgical patients. 2. Clinical rounds on all patients receiving epidural analgesia (EA), other forms of regional analgesia, or patient-controlled analgesia (PCA) every morning and throughout the day if necessary. 3. Additional consultations for postoperative pain management for other patients on request. 4. Assessment and documentation of the clinical status of the patient, quality of analgesia, and side effects. 5. Writing orders for further treatment. 6. Continuing consultations and informal education for ward nurses, physiotherapists, and surgical staff; formal medical training for ward nurses in postoperative pain management. Activity of the APS. From 1985 to 1992, 1947 patients on normal wards were treated (EA: 1736, PCA: 183). Epidural analgesia was performed using a standard protocol with bupivacaine 0.175% – 0.25% infused continuously with top-ups if needed (mean 240 mg/day, range 75 – 600 mg; median duration 7 days, range 1 – 53, Table 1). Demand for further treatment was proved by day-to-day withdrawal. Since the introduction of an APS, complications of EA such as hypotension (1985/1986: 5.1%; 1987/1992: 0.5%, Table 3) and insufficient analgesia due to dislocation or other technical complications could be reduced significantly (Table 3). Dermal infections were seen in 2.6% of patients, with a significantly higher incidence in patients with arteriosclerotic diseases (4.1%). Epidural opioids were used in only 46 selected cases on surgical wards. Nevertheless, 2 cases of marked respiratory depression occurred. The overall risk of complications during postoperative EA could be reduced from 1 : 11 cases in the first 2 years to 1 : 20 in the last 6 years since introducing the APS. For other regional procedures (e.g., interpleural analgesia) no complications were recorded. PCA was performed using a standard protocol with tramadol or piritramide without background infusion (Table 6). The loading dose was titrated in the recovery unit. The median duration of PCA was 4 days (range 1 – 23); the median dose of piritramide was 45 mg/day (range 3 – 226 mg). Two cases of somnolence and respiratory depression occurred. In this period there were 8 potential life-threatening complications due to postoperative pain therapy; 4 occurred during standard surgical pain management (3 cases of severe respiratory depression after i.m. and i.v. piritramide (unsuccessfull resuscitation), tramadol, and buprenorphine; 1 small child with multiorgan failure after paracetamol intoxication). In those cases the APS was not involved. Conclusions. There are insufficient data for comparison of the incidence of complications following standard management of postoperative pain relief without an APS, i.e., i.m. injections of opioids on request, but severe and sometimes lethal complications have been reported. Since the majority of patients used EA or PCA for several days, it is again emphasised that these techniques should not be restricted to high-dependency areas such as intensive care or recovery units. The introduction of an APS is an adequate approach to more efficient and safer pain management on surgical wards. This requires standard protocols (Table 7), standardised monitoring and trained ward nurses. Based on our experience, most complications develop slowly, and risk factors can be recognised early enough to avoid severe sequelae. The routine use of epidural opioids on surgical wards is not recommended unless special monitoring (e.g., pulse oximetry) is provided. Establishing an APS is a major future challenge for anaesthesiologists. Nevertheless, surgeons should also participate to improve the standard of pain management. We should be aware that this service can not be run efficiently during simultaneous activity in the operating room.